2 * libwebsockets - small server side websockets and web server implementation
4 * Copyright (C) 2010-2016 Andy Green <andy@warmcat.com>
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation:
9 * version 2.1 of the License.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
24 #ifndef LIBWEBSOCKET_H_3060898B846849FF9F88F5DB59B5950C
25 #define LIBWEBSOCKET_H_3060898B846849FF9F88F5DB59B5950C
36 #if defined(LWS_WITH_ESP8266)
43 #include "lws_config.h"
45 #if defined(WIN32) || defined(_WIN32)
46 #ifndef WIN32_LEAN_AND_MEAN
47 #define WIN32_LEAN_AND_MEAN
57 #define _O_RDONLY 0x0000
58 #define O_RDONLY _O_RDONLY
61 // Visual studio older than 2015 and WIN_CE has only _stricmp
62 #if (defined(_MSC_VER) && _MSC_VER < 1900) || defined(_WIN32_WCE)
63 #define strcasecmp _stricmp
64 #elif !defined(__MINGW32__)
65 #define strcasecmp stricmp
67 #define getdtablesize() 30000
69 #define LWS_INLINE __inline
71 #define LWS_WARN_UNUSED_RESULT
72 #define LWS_WARN_DEPRECATED
73 #define LWS_FORMAT(string_index)
77 #define LWS_EXTERN extern __declspec(dllexport)
79 #define LWS_EXTERN extern __declspec(dllimport)
85 #define LWS_INVALID_FILE INVALID_HANDLE_VALUE
86 #define LWS_O_RDONLY _O_RDONLY
88 #if !defined(__MINGW32__) && (!defined(_MSC_VER) || _MSC_VER < 1900) /* Visual Studio 2015 already defines this in <stdio.h> */
89 #define lws_snprintf _snprintf
93 #define __func__ __FUNCTION__
99 #if defined(__NetBSD__) || defined(__FreeBSD__)
100 #include <netinet/in.h>
103 #define LWS_INLINE inline
104 #define LWS_O_RDONLY O_RDONLY
106 #if !defined(LWS_WITH_ESP8266) && !defined(OPTEE_TA) && !defined(LWS_WITH_ESP32)
109 #define LWS_INVALID_FILE -1
111 #define getdtablesize() (20)
112 #if defined(LWS_WITH_ESP32)
113 #define LWS_INVALID_FILE NULL
115 #define LWS_INVALID_FILE NULL
119 #if defined(__GNUC__)
121 /* warn_unused_result attribute only supported by GCC 3.4 or later */
122 #if __GNUC__ >= 4 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4)
123 #define LWS_WARN_UNUSED_RESULT __attribute__((warn_unused_result))
125 #define LWS_WARN_UNUSED_RESULT
128 #define LWS_VISIBLE __attribute__((visibility("default")))
129 #define LWS_WARN_DEPRECATED __attribute__ ((deprecated))
130 #define LWS_FORMAT(string_index) __attribute__ ((format(printf, string_index, string_index+1)))
133 #define LWS_WARN_UNUSED_RESULT
134 #define LWS_WARN_DEPRECATED
135 #define LWS_FORMAT(string_index)
138 #if defined(__ANDROID__)
140 #define getdtablesize() sysconf(_SC_OPEN_MAX)
147 #endif /* LWS_USE_LIBEV */
150 #ifdef LWS_HAVE_UV_VERSION_H
151 #include <uv-version.h>
153 #endif /* LWS_USE_LIBUV */
156 #define LWS_EXTERN extern
162 #if !defined(OPTEE_TA)
163 #include <sys/time.h>
168 #ifdef LWS_OPENSSL_SUPPORT
171 #ifdef USE_OLD_CYASSL
172 #include <cyassl/openssl/ssl.h>
173 #include <cyassl/error-ssl.h>
175 #include <wolfssl/openssl/ssl.h>
176 #include <wolfssl/error-ssl.h>
177 #endif /* not USE_OLD_CYASSL */
179 #if defined(LWS_USE_POLARSSL)
180 #include <polarssl/ssl.h>
181 struct lws_polarssl_context {
182 x509_crt ca; /**< ca */
183 x509_crt certificate; /**< cert */
184 rsa_context key; /**< key */
186 typedef struct lws_polarssl_context SSL_CTX;
187 typedef ssl_context SSL;
189 #include <openssl/ssl.h>
190 #include <openssl/err.h>
191 #endif /* not USE_POLARSSL */
192 #endif /* not USE_WOLFSSL */
196 #define CONTEXT_PORT_NO_LISTEN -1
197 #define CONTEXT_PORT_NO_LISTEN_SERVER -2
199 /** \defgroup log Logging
203 * Lws provides flexible and filterable logging facilities, which can be
204 * used inside lws and in user code.
206 * Log categories may be individually filtered bitwise, and directed to built-in
207 * sinks for syslog-compatible logging, or a user-defined function.
211 enum lws_log_levels {
221 LLL_LATENCY = 1 << 9,
224 LLL_COUNT = 11 /* set to count of valid flags */
227 LWS_VISIBLE LWS_EXTERN void _lws_log(int filter, const char *format, ...) LWS_FORMAT(2);
228 LWS_VISIBLE LWS_EXTERN void _lws_logv(int filter, const char *format, va_list vl);
230 * lwsl_timestamp: generate logging timestamp string
232 * \param level: logging level
233 * \param p: char * buffer to take timestamp
234 * \param len: length of p
236 * returns length written in p
238 LWS_VISIBLE LWS_EXTERN int
239 lwsl_timestamp(int level, char *p, int len);
241 /* these guys are unconditionally included */
243 #define lwsl_err(...) _lws_log(LLL_ERR, __VA_ARGS__)
244 #define lwsl_user(...) _lws_log(LLL_USER, __VA_ARGS__)
246 #if !defined(LWS_WITH_NO_LOGS)
247 /* notice and warn are usually included by being compiled in */
248 #define lwsl_warn(...) _lws_log(LLL_WARN, __VA_ARGS__)
249 #define lwsl_notice(...) _lws_log(LLL_NOTICE, __VA_ARGS__)
252 * weaker logging can be deselected by telling CMake to build in RELEASE mode
253 * that gets rid of the overhead of checking while keeping _warn and _err
257 #if defined(LWS_WITH_ESP8266)
262 #if defined(LWS_WITH_NO_LOGS)
263 /* notice, warn and log are always compiled in */
264 #define lwsl_warn(...) _lws_log(LLL_WARN, __VA_ARGS__)
265 #define lwsl_notice(...) _lws_log(LLL_NOTICE, __VA_ARGS__)
267 #define lwsl_info(...) _lws_log(LLL_INFO, __VA_ARGS__)
268 #define lwsl_debug(...) _lws_log(LLL_DEBUG, __VA_ARGS__)
269 #define lwsl_parser(...) _lws_log(LLL_PARSER, __VA_ARGS__)
270 #define lwsl_header(...) _lws_log(LLL_HEADER, __VA_ARGS__)
271 #define lwsl_ext(...) _lws_log(LLL_EXT, __VA_ARGS__)
272 #define lwsl_client(...) _lws_log(LLL_CLIENT, __VA_ARGS__)
273 #define lwsl_latency(...) _lws_log(LLL_LATENCY, __VA_ARGS__)
275 * lwsl_hexdump() - helper to hexdump a buffer (DEBUG builds only)
277 * \param buf: buffer start to dump
278 * \param len: length of buffer to dump
280 LWS_VISIBLE LWS_EXTERN void lwsl_hexdump(void *buf, size_t len);
283 #if defined(LWS_WITH_NO_LOGS)
284 #define lwsl_warn(...) do {} while(0)
285 #define lwsl_notice(...) do {} while(0)
287 #define lwsl_info(...) do {} while(0)
288 #define lwsl_debug(...) do {} while(0)
289 #define lwsl_parser(...) do {} while(0)
290 #define lwsl_header(...) do {} while(0)
291 #define lwsl_ext(...) do {} while(0)
292 #define lwsl_client(...) do {} while(0)
293 #define lwsl_latency(...) do {} while(0)
294 #define lwsl_hexdump(a, b)
299 * lws_set_log_level() - Set the logging bitfield
300 * \param level: OR together the LLL_ debug contexts you want output from
301 * \param log_emit_function: NULL to leave it as it is, or a user-supplied
302 * function to perform log string emission instead of
303 * the default stderr one.
305 * log level defaults to "err", "warn" and "notice" contexts enabled and
306 * emission on stderr.
308 LWS_VISIBLE LWS_EXTERN void
309 lws_set_log_level(int level,
310 void (*log_emit_function)(int level, const char *line));
313 * lwsl_emit_syslog() - helper log emit function writes to system log
315 * \param level: one of LLL_ log level indexes
316 * \param line: log string
318 * You use this by passing the function pointer to lws_set_log_level(), to set
319 * it as the log emit function, it is not called directly.
321 LWS_VISIBLE LWS_EXTERN void
322 lwsl_emit_syslog(int level, const char *line);
325 * lwsl_visible() - returns true if the log level should be printed
327 * \param level: one of LLL_ log level indexes
329 * This is useful if you have to do work to generate the log content, you
330 * can skip the work if the log level used to print it is not actually
331 * enabled at runtime.
333 LWS_VISIBLE LWS_EXTERN int
334 lwsl_visible(int level);
341 #ifndef lws_container_of
342 #define lws_container_of(P,T,M) ((T *)((char *)(P) - offsetof(T, M)))
348 #define ARRAY_SIZE(x) (sizeof(x) / sizeof(x[0]))
351 /* api change list for user code to test against */
353 #define LWS_FEATURE_SERVE_HTTP_FILE_HAS_OTHER_HEADERS_ARG
355 /* the struct lws_protocols has the id field present */
356 #define LWS_FEATURE_PROTOCOLS_HAS_ID_FIELD
358 /* you can call lws_get_peer_write_allowance */
359 #define LWS_FEATURE_PROTOCOLS_HAS_PEER_WRITE_ALLOWANCE
361 /* extra parameter introduced in 917f43ab821 */
362 #define LWS_FEATURE_SERVE_HTTP_FILE_HAS_OTHER_HEADERS_LEN
364 /* File operations stuff exists */
365 #define LWS_FEATURE_FOPS
369 typedef SOCKET lws_sockfd_type;
370 typedef HANDLE lws_filefd_type;
371 #define lws_sockfd_valid(sfd) (!!sfd)
373 lws_sockfd_type fd; /**< file descriptor */
374 SHORT events; /**< which events to respond to */
375 SHORT revents; /**< which events happened */
377 #define LWS_POLLHUP (FD_CLOSE)
378 #define LWS_POLLIN (FD_READ | FD_ACCEPT)
379 #define LWS_POLLOUT (FD_WRITE)
383 #if defined(LWS_WITH_ESP8266)
385 #include <user_interface.h>
388 typedef struct espconn * lws_sockfd_type;
389 typedef void * lws_filefd_type;
390 #define lws_sockfd_valid(sfd) (!!sfd)
392 lws_sockfd_type fd; /**< fd related to */
393 short events; /**< which POLL... events to respond to */
394 short revents; /**< which POLL... events occurred */
396 #define POLLIN 0x0001
397 #define POLLPRI 0x0002
398 #define POLLOUT 0x0004
399 #define POLLERR 0x0008
400 #define POLLHUP 0x0010
401 #define POLLNVAL 0x0020
405 lws_sockfd_type esp8266_create_tcp_listen_socket(struct lws_vhost *vh);
406 void esp8266_tcp_stream_accept(lws_sockfd_type fd, struct lws *wsi);
412 int ets_snprintf(char *str, size_t size, const char *format, ...) LWS_FORMAT(3);
413 #define snprintf ets_snprintf
415 typedef os_timer_t uv_timer_t;
416 typedef void uv_cb_t(uv_timer_t *);
418 void os_timer_disarm(void *);
419 void os_timer_setfn(os_timer_t *, os_timer_func_t *, void *);
421 void ets_timer_arm_new(os_timer_t *, int, int, int);
423 //void os_timer_arm(os_timer_t *, int, int);
425 #define UV_VERSION_MAJOR 1
427 #define lws_uv_getloop(a, b) (NULL)
429 static inline void uv_timer_init(void *l, uv_timer_t *t)
432 memset(t, 0, sizeof(*t));
436 static inline void uv_timer_start(uv_timer_t *t, uv_cb_t *cb, int first, int rep)
438 os_timer_setfn(t, (os_timer_func_t *)cb, t);
440 os_timer_arm(t, first, !!rep);
443 static inline void uv_timer_stop(uv_timer_t *t)
449 #if defined(LWS_WITH_ESP32)
451 typedef int lws_sockfd_type;
452 typedef void * lws_filefd_type;
453 #define lws_sockfd_valid(sfd) (sfd >= 0)
455 lws_sockfd_type fd; /**< fd related to */
456 short events; /**< which POLL... events to respond to */
457 short revents; /**< which POLL... events occurred */
459 #define POLLIN 0x0001
460 #define POLLPRI 0x0002
461 #define POLLOUT 0x0004
462 #define POLLERR 0x0008
463 #define POLLHUP 0x0010
464 #define POLLNVAL 0x0020
466 #include "freertos/timers.h"
468 #if !defined(CONFIG_FREERTOS_HZ)
469 #define CONFIG_FREERTOS_HZ 100
472 typedef TimerHandle_t uv_timer_t;
473 typedef void uv_cb_t(uv_timer_t *);
474 typedef void * uv_handle_t;
476 struct timer_mapping {
481 #define UV_VERSION_MAJOR 1
483 #define lws_uv_getloop(a, b) (NULL)
485 static inline void uv_timer_init(void *l, uv_timer_t *t)
491 extern void esp32_uvtimer_cb(TimerHandle_t t);
493 static inline void uv_timer_start(uv_timer_t *t, uv_cb_t *cb, int first, int rep)
495 struct timer_mapping *tm = malloc(sizeof(*tm));
503 *t = xTimerCreate("x", pdMS_TO_TICKS(first), !!rep, tm,
504 (TimerCallbackFunction_t)esp32_uvtimer_cb);
508 static inline void uv_timer_stop(uv_timer_t *t)
513 static inline void uv_close(uv_handle_t *h, void *v)
515 free(pvTimerGetTimerID((uv_timer_t)h));
516 xTimerDelete(*(uv_timer_t *)h, 0);
523 typedef int lws_sockfd_type;
524 typedef int lws_filefd_type;
525 #define lws_sockfd_valid(sfd) (sfd >= 0)
529 #define lws_pollfd pollfd
530 #define LWS_POLLHUP (POLLHUP|POLLERR)
531 #define LWS_POLLIN (POLLIN)
532 #define LWS_POLLOUT (POLLOUT)
535 /** struct lws_pollargs - argument structure for all external poll related calls
536 * passed in via 'in' */
537 struct lws_pollargs {
538 lws_sockfd_type fd; /**< applicable socket descriptor */
539 int events; /**< the new event mask */
540 int prev_events; /**< the previous event mask */
544 struct lws_token_limits;
546 /*! \defgroup wsclose Websocket Close
548 * ##Websocket close frame control
550 * When we close a ws connection, we can send a reason code and a short
551 * UTF-8 description back with the close packet.
556 * NOTE: These public enums are part of the abi. If you want to add one,
557 * add it at where specified so existing users are unaffected.
559 /** enum lws_close_status - RFC6455 close status codes */
560 enum lws_close_status {
561 LWS_CLOSE_STATUS_NOSTATUS = 0,
562 LWS_CLOSE_STATUS_NORMAL = 1000,
563 /**< 1000 indicates a normal closure, meaning that the purpose for
564 which the connection was established has been fulfilled. */
565 LWS_CLOSE_STATUS_GOINGAWAY = 1001,
566 /**< 1001 indicates that an endpoint is "going away", such as a server
567 going down or a browser having navigated away from a page. */
568 LWS_CLOSE_STATUS_PROTOCOL_ERR = 1002,
569 /**< 1002 indicates that an endpoint is terminating the connection due
570 to a protocol error. */
571 LWS_CLOSE_STATUS_UNACCEPTABLE_OPCODE = 1003,
572 /**< 1003 indicates that an endpoint is terminating the connection
573 because it has received a type of data it cannot accept (e.g., an
574 endpoint that understands only text data MAY send this if it
575 receives a binary message). */
576 LWS_CLOSE_STATUS_RESERVED = 1004,
577 /**< Reserved. The specific meaning might be defined in the future. */
578 LWS_CLOSE_STATUS_NO_STATUS = 1005,
579 /**< 1005 is a reserved value and MUST NOT be set as a status code in a
580 Close control frame by an endpoint. It is designated for use in
581 applications expecting a status code to indicate that no status
582 code was actually present. */
583 LWS_CLOSE_STATUS_ABNORMAL_CLOSE = 1006,
584 /**< 1006 is a reserved value and MUST NOT be set as a status code in a
585 Close control frame by an endpoint. It is designated for use in
586 applications expecting a status code to indicate that the
587 connection was closed abnormally, e.g., without sending or
588 receiving a Close control frame. */
589 LWS_CLOSE_STATUS_INVALID_PAYLOAD = 1007,
590 /**< 1007 indicates that an endpoint is terminating the connection
591 because it has received data within a message that was not
592 consistent with the type of the message (e.g., non-UTF-8 [RFC3629]
593 data within a text message). */
594 LWS_CLOSE_STATUS_POLICY_VIOLATION = 1008,
595 /**< 1008 indicates that an endpoint is terminating the connection
596 because it has received a message that violates its policy. This
597 is a generic status code that can be returned when there is no
598 other more suitable status code (e.g., 1003 or 1009) or if there
599 is a need to hide specific details about the policy. */
600 LWS_CLOSE_STATUS_MESSAGE_TOO_LARGE = 1009,
601 /**< 1009 indicates that an endpoint is terminating the connection
602 because it has received a message that is too big for it to
604 LWS_CLOSE_STATUS_EXTENSION_REQUIRED = 1010,
605 /**< 1010 indicates that an endpoint (client) is terminating the
606 connection because it has expected the server to negotiate one or
607 more extension, but the server didn't return them in the response
608 message of the WebSocket handshake. The list of extensions that
609 are needed SHOULD appear in the /reason/ part of the Close frame.
610 Note that this status code is not used by the server, because it
611 can fail the WebSocket handshake instead */
612 LWS_CLOSE_STATUS_UNEXPECTED_CONDITION = 1011,
613 /**< 1011 indicates that a server is terminating the connection because
614 it encountered an unexpected condition that prevented it from
615 fulfilling the request. */
616 LWS_CLOSE_STATUS_TLS_FAILURE = 1015,
617 /**< 1015 is a reserved value and MUST NOT be set as a status code in a
618 Close control frame by an endpoint. It is designated for use in
619 applications expecting a status code to indicate that the
620 connection was closed due to a failure to perform a TLS handshake
621 (e.g., the server certificate can't be verified). */
623 /****** add new things just above ---^ ******/
625 LWS_CLOSE_STATUS_NOSTATUS_CONTEXT_DESTROY = 9999,
629 * lws_close_reason - Set reason and aux data to send with Close packet
630 * If you are going to return nonzero from the callback
631 * requesting the connection to close, you can optionally
632 * call this to set the reason the peer will be told if
635 * \param wsi: The websocket connection to set the close reason on
636 * \param status: A valid close status from websocket standard
637 * \param buf: NULL or buffer containing up to 124 bytes of auxiliary data
638 * \param len: Length of data in \param buf to send
640 LWS_VISIBLE LWS_EXTERN void
641 lws_close_reason(struct lws *wsi, enum lws_close_status status,
642 unsigned char *buf, size_t len);
648 /* needed even with extensions disabled for create context */
649 struct lws_extension;
651 /*! \defgroup usercb User Callback
653 * ##User protocol callback
655 * The protocol callback is the primary way lws interacts with
656 * user code. For one of a list of a few dozen reasons the callback gets
657 * called at some event to be handled.
659 * All of the events can be ignored, returning 0 is taken as "OK" and returning
660 * nonzero in most cases indicates that the connection should be closed.
666 * NOTE: These public enums are part of the abi. If you want to add one,
667 * add it at where specified so existing users are unaffected.
669 /** enum lws_callback_reasons - reason you're getting a protocol callback */
670 enum lws_callback_reasons {
671 LWS_CALLBACK_ESTABLISHED = 0,
672 /**< (VH) after the server completes a handshake with an incoming
673 * client. If you built the library with ssl support, in is a
674 * pointer to the ssl struct associated with the connection or NULL.*/
675 LWS_CALLBACK_CLIENT_CONNECTION_ERROR = 1,
676 /**< the request client connection has been unable to complete a
677 * handshake with the remote server. If in is non-NULL, you can
678 * find an error string of length len where it points to
680 * Diagnostic strings that may be returned include
682 * "getaddrinfo (ipv6) failed"
683 * "unknown address family"
684 * "getaddrinfo (ipv4) failed"
685 * "set socket opts failed"
686 * "insert wsi failed"
687 * "lws_ssl_client_connect1 failed"
688 * "lws_ssl_client_connect2 failed"
692 * "HS: Redirect code but no Location"
693 * "HS: URI did not parse"
694 * "HS: Redirect failed"
695 * "HS: Server did not return 200"
697 * "HS: disallowed by client filter"
698 * "HS: disallowed at ESTABLISHED"
699 * "HS: ACCEPT missing"
700 * "HS: ws upgrade response not 101"
701 * "HS: UPGRADE missing"
702 * "HS: Upgrade to something other than websocket"
703 * "HS: CONNECTION missing"
704 * "HS: UPGRADE malformed"
705 * "HS: PROTOCOL malformed"
706 * "HS: Cannot match protocol"
707 * "HS: EXT: list too big"
708 * "HS: EXT: failed setting defaults"
709 * "HS: EXT: failed parsing defaults"
710 * "HS: EXT: failed parsing options"
711 * "HS: EXT: Rejects server options"
712 * "HS: EXT: unknown ext"
713 * "HS: Accept hash wrong"
714 * "HS: Rejected by filter cb"
716 * "HS: SO_SNDBUF failed"
717 * "HS: Rejected at CLIENT_ESTABLISHED"
719 LWS_CALLBACK_CLIENT_FILTER_PRE_ESTABLISH = 2,
720 /**< this is the last chance for the client user code to examine the
721 * http headers and decide to reject the connection. If the
722 * content in the headers is interesting to the
723 * client (url, etc) it needs to copy it out at
724 * this point since it will be destroyed before
725 * the CLIENT_ESTABLISHED call */
726 LWS_CALLBACK_CLIENT_ESTABLISHED = 3,
727 /**< after your client connection completed
728 * a handshake with the remote server */
729 LWS_CALLBACK_CLOSED = 4,
730 /**< when the websocket session ends */
731 LWS_CALLBACK_CLOSED_HTTP = 5,
732 /**< when a HTTP (non-websocket) session ends */
733 LWS_CALLBACK_RECEIVE = 6,
734 /**< data has appeared for this server endpoint from a
735 * remote client, it can be found at *in and is
737 LWS_CALLBACK_RECEIVE_PONG = 7,
738 /**< servers receive PONG packets with this callback reason */
739 LWS_CALLBACK_CLIENT_RECEIVE = 8,
740 /**< data has appeared from the server for the client connection, it
741 * can be found at *in and is len bytes long */
742 LWS_CALLBACK_CLIENT_RECEIVE_PONG = 9,
743 /**< clients receive PONG packets with this callback reason */
744 LWS_CALLBACK_CLIENT_WRITEABLE = 10,
745 /**< If you call lws_callback_on_writable() on a connection, you will
746 * get one of these callbacks coming when the connection socket
747 * is able to accept another write packet without blocking.
748 * If it already was able to take another packet without blocking,
749 * you'll get this callback at the next call to the service loop
750 * function. Notice that CLIENTs get LWS_CALLBACK_CLIENT_WRITEABLE
751 * and servers get LWS_CALLBACK_SERVER_WRITEABLE. */
752 LWS_CALLBACK_SERVER_WRITEABLE = 11,
753 /**< See LWS_CALLBACK_CLIENT_WRITEABLE */
754 LWS_CALLBACK_HTTP = 12,
755 /**< an http request has come from a client that is not
756 * asking to upgrade the connection to a websocket
757 * one. This is a chance to serve http content,
758 * for example, to send a script to the client
759 * which will then open the websockets connection.
760 * in points to the URI path requested and
761 * lws_serve_http_file() makes it very
762 * simple to send back a file to the client.
763 * Normally after sending the file you are done
764 * with the http connection, since the rest of the
765 * activity will come by websockets from the script
766 * that was delivered by http, so you will want to
767 * return 1; to close and free up the connection. */
768 LWS_CALLBACK_HTTP_BODY = 13,
769 /**< the next len bytes data from the http
770 * request body HTTP connection is now available in in. */
771 LWS_CALLBACK_HTTP_BODY_COMPLETION = 14,
772 /**< the expected amount of http request body has been delivered */
773 LWS_CALLBACK_HTTP_FILE_COMPLETION = 15,
774 /**< a file requested to be sent down http link has completed. */
775 LWS_CALLBACK_HTTP_WRITEABLE = 16,
776 /**< you can write more down the http protocol link now. */
777 LWS_CALLBACK_FILTER_NETWORK_CONNECTION = 17,
778 /**< called when a client connects to
779 * the server at network level; the connection is accepted but then
780 * passed to this callback to decide whether to hang up immediately
781 * or not, based on the client IP. in contains the connection
782 * socket's descriptor. Since the client connection information is
783 * not available yet, wsi still pointing to the main server socket.
784 * Return non-zero to terminate the connection before sending or
785 * receiving anything. Because this happens immediately after the
786 * network connection from the client, there's no websocket protocol
787 * selected yet so this callback is issued only to protocol 0. */
788 LWS_CALLBACK_FILTER_HTTP_CONNECTION = 18,
789 /**< called when the request has
790 * been received and parsed from the client, but the response is
791 * not sent yet. Return non-zero to disallow the connection.
792 * user is a pointer to the connection user space allocation,
793 * in is the URI, eg, "/"
794 * In your handler you can use the public APIs
795 * lws_hdr_total_length() / lws_hdr_copy() to access all of the
796 * headers using the header enums lws_token_indexes from
797 * libwebsockets.h to check for and read the supported header
798 * presence and content before deciding to allow the http
799 * connection to proceed or to kill the connection. */
800 LWS_CALLBACK_SERVER_NEW_CLIENT_INSTANTIATED = 19,
801 /**< A new client just had
802 * been connected, accepted, and instantiated into the pool. This
803 * callback allows setting any relevant property to it. Because this
804 * happens immediately after the instantiation of a new client,
805 * there's no websocket protocol selected yet so this callback is
806 * issued only to protocol 0. Only wsi is defined, pointing to the
807 * new client, and the return value is ignored. */
808 LWS_CALLBACK_FILTER_PROTOCOL_CONNECTION = 20,
809 /**< called when the handshake has
810 * been received and parsed from the client, but the response is
811 * not sent yet. Return non-zero to disallow the connection.
812 * user is a pointer to the connection user space allocation,
813 * in is the requested protocol name
814 * In your handler you can use the public APIs
815 * lws_hdr_total_length() / lws_hdr_copy() to access all of the
816 * headers using the header enums lws_token_indexes from
817 * libwebsockets.h to check for and read the supported header
818 * presence and content before deciding to allow the handshake
819 * to proceed or to kill the connection. */
820 LWS_CALLBACK_OPENSSL_LOAD_EXTRA_CLIENT_VERIFY_CERTS = 21,
821 /**< if configured for
822 * including OpenSSL support, this callback allows your user code
823 * to perform extra SSL_CTX_load_verify_locations() or similar
824 * calls to direct OpenSSL where to find certificates the client
825 * can use to confirm the remote server identity. user is the
826 * OpenSSL SSL_CTX* */
827 LWS_CALLBACK_OPENSSL_LOAD_EXTRA_SERVER_VERIFY_CERTS = 22,
828 /**< if configured for
829 * including OpenSSL support, this callback allows your user code
830 * to load extra certifcates into the server which allow it to
831 * verify the validity of certificates returned by clients. user
832 * is the server's OpenSSL SSL_CTX* */
833 LWS_CALLBACK_OPENSSL_PERFORM_CLIENT_CERT_VERIFICATION = 23,
834 /**< if the libwebsockets vhost was created with the option
835 * LWS_SERVER_OPTION_REQUIRE_VALID_OPENSSL_CLIENT_CERT, then this
836 * callback is generated during OpenSSL verification of the cert
837 * sent from the client. It is sent to protocol[0] callback as
838 * no protocol has been negotiated on the connection yet.
839 * Notice that the libwebsockets context and wsi are both NULL
840 * during this callback. See
841 * http://www.openssl.org/docs/ssl/SSL_CTX_set_verify.html
842 * to understand more detail about the OpenSSL callback that
843 * generates this libwebsockets callback and the meanings of the
844 * arguments passed. In this callback, user is the x509_ctx,
845 * in is the ssl pointer and len is preverify_ok
846 * Notice that this callback maintains libwebsocket return
847 * conventions, return 0 to mean the cert is OK or 1 to fail it.
848 * This also means that if you don't handle this callback then
849 * the default callback action of returning 0 allows the client
851 LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER = 24,
852 /**< this callback happens
853 * when a client handshake is being compiled. user is NULL,
854 * in is a char **, it's pointing to a char * which holds the
855 * next location in the header buffer where you can add
856 * headers, and len is the remaining space in the header buffer,
857 * which is typically some hundreds of bytes. So, to add a canned
858 * cookie, your handler code might look similar to:
860 * char **p = (char **)in;
865 * *p += sprintf(*p, "Cookie: a=b\x0d\x0a");
869 * Notice if you add anything, you just have to take care about
870 * the CRLF on the line you added. Obviously this callback is
871 * optional, if you don't handle it everything is fine.
873 * Notice the callback is coming to protocols[0] all the time,
874 * because there is no specific protocol negotiated yet. */
875 LWS_CALLBACK_CONFIRM_EXTENSION_OKAY = 25,
876 /**< When the server handshake code
877 * sees that it does support a requested extension, before
878 * accepting the extension by additing to the list sent back to
879 * the client it gives this callback just to check that it's okay
880 * to use that extension. It calls back to the requested protocol
881 * and with in being the extension name, len is 0 and user is
882 * valid. Note though at this time the ESTABLISHED callback hasn't
883 * happened yet so if you initialize user content there, user
884 * content during this callback might not be useful for anything.
885 * Notice this callback comes to protocols[0]. */
886 LWS_CALLBACK_CLIENT_CONFIRM_EXTENSION_SUPPORTED = 26,
888 * connection is being prepared to start a handshake to a server,
889 * each supported extension is checked with protocols[0] callback
890 * with this reason, giving the user code a chance to suppress the
891 * claim to support that extension by returning non-zero. If
892 * unhandled, by default 0 will be returned and the extension
893 * support included in the header to the server. Notice this
894 * callback comes to protocols[0]. */
895 LWS_CALLBACK_PROTOCOL_INIT = 27,
896 /**< One-time call per protocol, per-vhost using it, so it can
897 * do initial setup / allocations etc */
898 LWS_CALLBACK_PROTOCOL_DESTROY = 28,
899 /**< One-time call per protocol, per-vhost using it, indicating
900 * this protocol won't get used at all after this callback, the
901 * vhost is getting destroyed. Take the opportunity to
902 * deallocate everything that was allocated by the protocol. */
903 LWS_CALLBACK_WSI_CREATE = 29,
904 /**< outermost (earliest) wsi create notification to protocols[0] */
905 LWS_CALLBACK_WSI_DESTROY = 30,
906 /**< outermost (latest) wsi destroy notification to protocols[0] */
907 LWS_CALLBACK_GET_THREAD_ID = 31,
908 /**< lws can accept callback when writable requests from other
909 * threads, if you implement this callback and return an opaque
910 * current thread ID integer. */
912 /* external poll() management support */
913 LWS_CALLBACK_ADD_POLL_FD = 32,
914 /**< lws normally deals with its poll() or other event loop
915 * internally, but in the case you are integrating with another
916 * server you will need to have lws sockets share a
917 * polling array with the other server. This and the other
918 * POLL_FD related callbacks let you put your specialized
919 * poll array interface code in the callback for protocol 0, the
920 * first protocol you support, usually the HTTP protocol in the
922 * This callback happens when a socket needs to be
923 * added to the polling loop: in points to a struct
924 * lws_pollargs; the fd member of the struct is the file
925 * descriptor, and events contains the active events
927 * If you are using the internal lws polling / event loop
928 * you can just ignore these callbacks. */
929 LWS_CALLBACK_DEL_POLL_FD = 33,
930 /**< This callback happens when a socket descriptor
931 * needs to be removed from an external polling array. in is
932 * again the struct lws_pollargs containing the fd member
933 * to be removed. If you are using the internal polling
934 * loop, you can just ignore it. */
935 LWS_CALLBACK_CHANGE_MODE_POLL_FD = 34,
936 /**< This callback happens when lws wants to modify the events for
938 * in is the struct lws_pollargs with the fd to change.
939 * The new event mask is in events member and the old mask is in
940 * the prev_events member.
941 * If you are using the internal polling loop, you can just ignore
943 LWS_CALLBACK_LOCK_POLL = 35,
944 /**< These allow the external poll changes driven
945 * by lws to participate in an external thread locking
946 * scheme around the changes, so the whole thing is threadsafe.
947 * These are called around three activities in the library,
948 * - inserting a new wsi in the wsi / fd table (len=1)
949 * - deleting a wsi from the wsi / fd table (len=1)
950 * - changing a wsi's POLLIN/OUT state (len=0)
951 * Locking and unlocking external synchronization objects when
952 * len == 1 allows external threads to be synchronized against
953 * wsi lifecycle changes if it acquires the same lock for the
954 * duration of wsi dereference from the other thread context. */
955 LWS_CALLBACK_UNLOCK_POLL = 36,
956 /**< See LWS_CALLBACK_LOCK_POLL, ignore if using lws internal poll */
958 LWS_CALLBACK_OPENSSL_CONTEXT_REQUIRES_PRIVATE_KEY = 37,
959 /**< if configured for including OpenSSL support but no private key
960 * file has been specified (ssl_private_key_filepath is NULL), this is
961 * called to allow the user to set the private key directly via
962 * libopenssl and perform further operations if required; this might be
963 * useful in situations where the private key is not directly accessible
964 * by the OS, for example if it is stored on a smartcard.
965 * user is the server's OpenSSL SSL_CTX* */
966 LWS_CALLBACK_WS_PEER_INITIATED_CLOSE = 38,
967 /**< The peer has sent an unsolicited Close WS packet. in and
968 * len are the optional close code (first 2 bytes, network
969 * order) and the optional additional information which is not
970 * defined in the standard, and may be a string or non-human- readable data.
971 * If you return 0 lws will echo the close and then close the
972 * connection. If you return nonzero lws will just close the
975 LWS_CALLBACK_WS_EXT_DEFAULTS = 39,
978 LWS_CALLBACK_CGI = 40,
980 LWS_CALLBACK_CGI_TERMINATED = 41,
982 LWS_CALLBACK_CGI_STDIN_DATA = 42,
984 LWS_CALLBACK_CGI_STDIN_COMPLETED = 43,
986 LWS_CALLBACK_ESTABLISHED_CLIENT_HTTP = 44,
988 LWS_CALLBACK_CLOSED_CLIENT_HTTP = 45,
990 LWS_CALLBACK_RECEIVE_CLIENT_HTTP = 46,
992 LWS_CALLBACK_COMPLETED_CLIENT_HTTP = 47,
994 LWS_CALLBACK_RECEIVE_CLIENT_HTTP_READ = 48,
996 LWS_CALLBACK_HTTP_BIND_PROTOCOL = 49,
998 LWS_CALLBACK_HTTP_DROP_PROTOCOL = 50,
1000 LWS_CALLBACK_CHECK_ACCESS_RIGHTS = 51,
1002 LWS_CALLBACK_PROCESS_HTML = 52,
1004 LWS_CALLBACK_ADD_HEADERS = 53,
1006 LWS_CALLBACK_SESSION_INFO = 54,
1009 LWS_CALLBACK_GS_EVENT = 55,
1011 LWS_CALLBACK_HTTP_PMO = 56,
1012 /**< per-mount options for this connection, called before
1013 * the normal LWS_CALLBACK_HTTP when the mount has per-mount
1016 LWS_CALLBACK_CLIENT_HTTP_WRITEABLE = 57,
1017 /**< when doing an HTTP type client connection, you can call
1018 * lws_client_http_body_pending(wsi, 1) from
1019 * LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER to get these callbacks
1020 * sending the HTTP headers.
1022 * From this callback, when you have sent everything, you should let
1023 * lws know by calling lws_client_http_body_pending(wsi, 0)
1025 LWS_CALLBACK_OPENSSL_PERFORM_SERVER_CERT_VERIFICATION = 58,
1026 /**< Similar to LWS_CALLBACK_OPENSSL_PERFORM_CLIENT_CERT_VERIFICATION
1027 * this callback is called during OpenSSL verification of the cert
1028 * sent from the server to the client. It is sent to protocol[0]
1029 * callback as no protocol has been negotiated on the connection yet.
1030 * Notice that the wsi is set because lws_client_connect_via_info was
1033 * See http://www.openssl.org/docs/ssl/SSL_CTX_set_verify.html
1034 * to understand more detail about the OpenSSL callback that
1035 * generates this libwebsockets callback and the meanings of the
1036 * arguments passed. In this callback, user is the x509_ctx,
1037 * in is the ssl pointer and len is preverify_ok.
1039 * THIS IS NOT RECOMMENDED BUT if a cert validation error shall be
1040 * overruled and cert shall be accepted as ok,
1041 * X509_STORE_CTX_set_error((X509_STORE_CTX*)user, X509_V_OK); must be
1042 * called and return value must be 0 to mean the cert is OK;
1043 * returning 1 will fail the cert in any case.
1045 * This also means that if you don't handle this callback then
1046 * the default callback action of returning 0 will not accept the
1047 * certificate in case of a validation error decided by the SSL lib.
1049 * This is expected and secure behaviour when validating certificates.
1051 * Note: LCCSCF_ALLOW_SELFSIGNED and
1052 * LCCSCF_SKIP_SERVER_CERT_HOSTNAME_CHECK still work without this
1053 * callback being implemented.
1055 LWS_CALLBACK_RAW_RX = 59,
1056 /**< RAW mode connection RX */
1057 LWS_CALLBACK_RAW_CLOSE = 60,
1058 /**< RAW mode connection is closing */
1059 LWS_CALLBACK_RAW_WRITEABLE = 61,
1060 /**< RAW mode connection may be written */
1061 LWS_CALLBACK_RAW_ADOPT = 62,
1062 /**< RAW mode connection was adopted (equivalent to 'created') */
1064 /****** add new things just above ---^ ******/
1066 LWS_CALLBACK_USER = 1000,
1067 /**< user code can use any including / above without fear of clashes */
1073 * typedef lws_callback_function() - User server actions
1074 * \param wsi: Opaque websocket instance pointer
1075 * \param reason: The reason for the call
1076 * \param user: Pointer to per-session user data allocated by library
1077 * \param in: Pointer used for some callback reasons
1078 * \param len: Length set for some callback reasons
1080 * This callback is the way the user controls what is served. All the
1081 * protocol detail is hidden and handled by the library.
1083 * For each connection / session there is user data allocated that is
1084 * pointed to by "user". You set the size of this user data area when
1085 * the library is initialized with lws_create_server.
1088 lws_callback_function(struct lws *wsi, enum lws_callback_reasons reason,
1089 void *user, void *in, size_t len);
1092 /*! \defgroup extensions
1094 * ##Extension releated functions
1096 * Ws defines optional extensions, lws provides the ability to implement these
1097 * in user code if so desired.
1099 * We provide one extensions permessage-deflate.
1104 * NOTE: These public enums are part of the abi. If you want to add one,
1105 * add it at where specified so existing users are unaffected.
1107 enum lws_extension_callback_reasons {
1108 LWS_EXT_CB_SERVER_CONTEXT_CONSTRUCT = 0,
1109 LWS_EXT_CB_CLIENT_CONTEXT_CONSTRUCT = 1,
1110 LWS_EXT_CB_SERVER_CONTEXT_DESTRUCT = 2,
1111 LWS_EXT_CB_CLIENT_CONTEXT_DESTRUCT = 3,
1112 LWS_EXT_CB_CONSTRUCT = 4,
1113 LWS_EXT_CB_CLIENT_CONSTRUCT = 5,
1114 LWS_EXT_CB_CHECK_OK_TO_REALLY_CLOSE = 6,
1115 LWS_EXT_CB_CHECK_OK_TO_PROPOSE_EXTENSION = 7,
1116 LWS_EXT_CB_DESTROY = 8,
1117 LWS_EXT_CB_DESTROY_ANY_WSI_CLOSING = 9,
1118 LWS_EXT_CB_ANY_WSI_ESTABLISHED = 10,
1119 LWS_EXT_CB_PACKET_RX_PREPARSE = 11,
1120 LWS_EXT_CB_PACKET_TX_PRESEND = 12,
1121 LWS_EXT_CB_PACKET_TX_DO_SEND = 13,
1122 LWS_EXT_CB_HANDSHAKE_REPLY_TX = 14,
1123 LWS_EXT_CB_FLUSH_PENDING_TX = 15,
1124 LWS_EXT_CB_EXTENDED_PAYLOAD_RX = 16,
1125 LWS_EXT_CB_CAN_PROXY_CLIENT_CONNECTION = 17,
1126 LWS_EXT_CB_1HZ = 18,
1127 LWS_EXT_CB_REQUEST_ON_WRITEABLE = 19,
1128 LWS_EXT_CB_IS_WRITEABLE = 20,
1129 LWS_EXT_CB_PAYLOAD_TX = 21,
1130 LWS_EXT_CB_PAYLOAD_RX = 22,
1131 LWS_EXT_CB_OPTION_DEFAULT = 23,
1132 LWS_EXT_CB_OPTION_SET = 24,
1133 LWS_EXT_CB_OPTION_CONFIRM = 25,
1134 LWS_EXT_CB_NAMED_OPTION_SET = 26,
1136 /****** add new things just above ---^ ******/
1139 /** enum lws_ext_options_types */
1140 enum lws_ext_options_types {
1141 EXTARG_NONE, /**< does not take an argument */
1142 EXTARG_DEC, /**< requires a decimal argument */
1143 EXTARG_OPT_DEC /**< may have an optional decimal argument */
1145 /* Add new things just above here ---^
1146 * This is part of the ABI, don't needlessly break compatibility */
1149 /** struct lws_ext_options - Option arguments to the extension. These are
1150 * used in the negotiation at ws upgrade time.
1151 * The helper function lws_ext_parse_options()
1152 * uses these to generate callbacks */
1153 struct lws_ext_options {
1154 const char *name; /**< Option name, eg, "server_no_context_takeover" */
1155 enum lws_ext_options_types type; /**< What kind of args the option can take */
1157 /* Add new things just above here ---^
1158 * This is part of the ABI, don't needlessly break compatibility */
1161 /** struct lws_ext_option_arg */
1162 struct lws_ext_option_arg {
1163 const char *option_name; /**< may be NULL, option_index used then */
1164 int option_index; /**< argument ordinal to use if option_name missing */
1165 const char *start; /**< value */
1166 int len; /**< length of value */
1170 * typedef lws_extension_callback_function() - Hooks to allow extensions to operate
1171 * \param context: Websockets context
1172 * \param ext: This extension
1173 * \param wsi: Opaque websocket instance pointer
1174 * \param reason: The reason for the call
1175 * \param user: Pointer to ptr to per-session user data allocated by library
1176 * \param in: Pointer used for some callback reasons
1177 * \param len: Length set for some callback reasons
1179 * Each extension that is active on a particular connection receives
1180 * callbacks during the connection lifetime to allow the extension to
1181 * operate on websocket data and manage itself.
1183 * Libwebsockets takes care of allocating and freeing "user" memory for
1184 * each active extension on each connection. That is what is pointed to
1185 * by the user parameter.
1187 * LWS_EXT_CB_CONSTRUCT: called when the server has decided to
1188 * select this extension from the list provided by the client,
1189 * just before the server will send back the handshake accepting
1190 * the connection with this extension active. This gives the
1191 * extension a chance to initialize its connection context found
1194 * LWS_EXT_CB_CLIENT_CONSTRUCT: same as LWS_EXT_CB_CONSTRUCT
1195 * but called when client is instantiating this extension. Some
1196 * extensions will work the same on client and server side and then
1197 * you can just merge handlers for both CONSTRUCTS.
1199 * LWS_EXT_CB_DESTROY: called when the connection the extension was
1200 * being used on is about to be closed and deallocated. It's the
1201 * last chance for the extension to deallocate anything it has
1202 * allocated in the user data (pointed to by user) before the
1203 * user data is deleted. This same callback is used whether you
1204 * are in client or server instantiation context.
1206 * LWS_EXT_CB_PACKET_RX_PREPARSE: when this extension was active on
1207 * a connection, and a packet of data arrived at the connection,
1208 * it is passed to this callback to give the extension a chance to
1209 * change the data, eg, decompress it. user is pointing to the
1210 * extension's private connection context data, in is pointing
1211 * to an lws_tokens struct, it consists of a char * pointer called
1212 * token, and an int called token_len. At entry, these are
1213 * set to point to the received buffer and set to the content
1214 * length. If the extension will grow the content, it should use
1215 * a new buffer allocated in its private user context data and
1216 * set the pointed-to lws_tokens members to point to its buffer.
1218 * LWS_EXT_CB_PACKET_TX_PRESEND: this works the same way as
1219 * LWS_EXT_CB_PACKET_RX_PREPARSE above, except it gives the
1220 * extension a chance to change websocket data just before it will
1221 * be sent out. Using the same lws_token pointer scheme in in,
1222 * the extension can change the buffer and the length to be
1223 * transmitted how it likes. Again if it wants to grow the
1224 * buffer safely, it should copy the data into its own buffer and
1225 * set the lws_tokens token pointer to it.
1227 * LWS_EXT_CB_ARGS_VALIDATE:
1230 lws_extension_callback_function(struct lws_context *context,
1231 const struct lws_extension *ext, struct lws *wsi,
1232 enum lws_extension_callback_reasons reason,
1233 void *user, void *in, size_t len);
1235 /** struct lws_extension - An extension we support */
1236 struct lws_extension {
1237 const char *name; /**< Formal extension name, eg, "permessage-deflate" */
1238 lws_extension_callback_function *callback; /**< Service callback */
1239 const char *client_offer; /**< String containing exts and options client offers */
1241 /* Add new things just above here ---^
1242 * This is part of the ABI, don't needlessly break compatibility */
1246 * lws_set_extension_option(): set extension option if possible
1248 * \param wsi: websocket connection
1249 * \param ext_name: name of ext, like "permessage-deflate"
1250 * \param opt_name: name of option, like "rx_buf_size"
1251 * \param opt_val: value to set option to
1253 LWS_VISIBLE LWS_EXTERN int
1254 lws_set_extension_option(struct lws *wsi, const char *ext_name,
1255 const char *opt_name, const char *opt_val);
1257 #ifndef LWS_NO_EXTENSIONS
1258 /* lws_get_internal_extensions() - DEPRECATED
1260 * \Deprecated There is no longer a set internal extensions table. The table is provided
1261 * by user code along with application-specific settings. See the test
1262 * client and server for how to do.
1264 static LWS_INLINE LWS_WARN_DEPRECATED const struct lws_extension *
1265 lws_get_internal_extensions(void) { return NULL; }
1268 * lws_ext_parse_options() - deal with parsing negotiated extension options
1270 * \param ext: related extension struct
1271 * \param wsi: websocket connection
1272 * \param ext_user: per-connection extension private data
1273 * \param opts: list of supported options
1274 * \param o: option string to parse
1275 * \param len: length
1277 LWS_VISIBLE LWS_EXTERN int LWS_WARN_UNUSED_RESULT
1278 lws_ext_parse_options(const struct lws_extension *ext, struct lws *wsi,
1279 void *ext_user, const struct lws_ext_options *opts,
1280 const char *o, int len);
1283 /** lws_extension_callback_pm_deflate() - extension for RFC7692
1285 * \param context: lws context
1286 * \param ext: related lws_extension struct
1287 * \param wsi: websocket connection
1288 * \param reason: incoming callback reason
1289 * \param user: per-connection extension private data
1290 * \param in: pointer parameter
1291 * \param len: length parameter
1293 * Built-in callback implementing RFC7692 permessage-deflate
1296 int lws_extension_callback_pm_deflate(
1297 struct lws_context *context, const struct lws_extension *ext,
1298 struct lws *wsi, enum lws_extension_callback_reasons reason,
1299 void *user, void *in, size_t len);
1302 * The internal exts are part of the public abi
1303 * If we add more extensions, publish the callback here ------v
1307 /*! \defgroup Protocols-and-Plugins Protocols and Plugins
1310 * ##Protocol and protocol plugin -related apis
1312 * Protocols bind ws protocol names to a custom callback specific to that
1313 * protocol implementaion.
1315 * A list of protocols can be passed in at context creation time, but it is
1316 * also legal to leave that NULL and add the protocols and their callback code
1319 * Plugins are much preferable compared to cut and pasting code into an
1320 * application each time, since they can be used standalone.
1323 /** struct lws_protocols - List of protocols and handlers client or server
1326 struct lws_protocols {
1328 /**< Protocol name that must match the one given in the client
1329 * Javascript new WebSocket(url, 'protocol') name. */
1330 lws_callback_function *callback;
1331 /**< The service callback used for this protocol. It allows the
1332 * service action for an entire protocol to be encapsulated in
1333 * the protocol-specific callback */
1334 size_t per_session_data_size;
1335 /**< Each new connection using this protocol gets
1336 * this much memory allocated on connection establishment and
1337 * freed on connection takedown. A pointer to this per-connection
1338 * allocation is passed into the callback in the 'user' parameter */
1339 size_t rx_buffer_size;
1340 /**< lws allocates this much space for rx data and informs callback
1341 * when something came. Due to rx flow control, the callback may not
1342 * be able to consume it all without having to return to the event
1343 * loop. That is supported in lws.
1345 * This also controls how much may be sent at once at the moment,
1346 * although this is likely to change.
1349 /**< ignored by lws, but useful to contain user information bound
1350 * to the selected protocol. For example if this protocol was
1351 * called "myprotocol-v2", you might set id to 2, and the user
1352 * code that acts differently according to the version can do so by
1353 * switch (wsi->protocol->id), user code might use some bits as
1354 * capability flags based on selected protocol version, etc. */
1355 void *user; /**< ignored by lws, but user code can pass a pointer
1356 here it can later access from the protocol callback */
1358 /* Add new things just above here ---^
1359 * This is part of the ABI, don't needlessly break compatibility */
1365 * lws_vhost_name_to_protocol() - get vhost's protocol object from its name
1367 * \param vh: vhost to search
1368 * \param name: protocol name
1370 * Returns NULL or a pointer to the vhost's protocol of the requested name
1372 LWS_VISIBLE LWS_EXTERN const struct lws_protocols *
1373 lws_vhost_name_to_protocol(struct lws_vhost *vh, const char *name);
1376 * lws_get_protocol() - Returns a protocol pointer from a websocket
1378 * \param wsi: pointer to struct websocket you want to know the protocol of
1381 * Some apis can act on all live connections of a given protocol,
1382 * this is how you can get a pointer to the active protocol if needed.
1384 LWS_VISIBLE LWS_EXTERN const struct lws_protocols *
1385 lws_get_protocol(struct lws *wsi);
1387 /** lws_protocol_get() - deprecated: use lws_get_protocol */
1388 LWS_VISIBLE LWS_EXTERN const struct lws_protocols *
1389 lws_protocol_get(struct lws *wsi) LWS_WARN_DEPRECATED;
1392 * lws_protocol_vh_priv_zalloc() - Allocate and zero down a protocol's per-vhost
1394 * \param vhost: vhost the instance is related to
1395 * \param prot: protocol the instance is related to
1396 * \param size: bytes to allocate
1398 * Protocols often find it useful to allocate a per-vhost struct, this is a
1399 * helper to be called in the per-vhost init LWS_CALLBACK_PROTOCOL_INIT
1401 LWS_VISIBLE LWS_EXTERN void *
1402 lws_protocol_vh_priv_zalloc(struct lws_vhost *vhost, const struct lws_protocols *prot,
1406 * lws_protocol_vh_priv_get() - retreive a protocol's per-vhost storage
1408 * \param vhost: vhost the instance is related to
1409 * \param prot: protocol the instance is related to
1411 * Recover a pointer to the allocated per-vhost storage for the protocol created
1412 * by lws_protocol_vh_priv_zalloc() earlier
1414 LWS_VISIBLE LWS_EXTERN void *
1415 lws_protocol_vh_priv_get(struct lws_vhost *vhost, const struct lws_protocols *prot);
1418 * lws_finalize_startup() - drop initial process privileges
1420 * \param context: lws context
1422 * This is called after the end of the vhost protocol initializations, but
1423 * you may choose to call it earlier
1425 LWS_VISIBLE LWS_EXTERN int
1426 lws_finalize_startup(struct lws_context *context);
1428 LWS_VISIBLE LWS_EXTERN int
1429 lws_protocol_init(struct lws_context *context);
1431 #ifdef LWS_WITH_PLUGINS
1433 /* PLUGINS implies LIBUV */
1435 #define LWS_PLUGIN_API_MAGIC 180
1437 /** struct lws_plugin_capability - how a plugin introduces itself to lws */
1438 struct lws_plugin_capability {
1439 unsigned int api_magic; /**< caller fills this in, plugin fills rest */
1440 const struct lws_protocols *protocols; /**< array of supported protocols provided by plugin */
1441 int count_protocols; /**< how many protocols */
1442 const struct lws_extension *extensions; /**< array of extensions provided by plugin */
1443 int count_extensions; /**< how many extensions */
1446 typedef int (*lws_plugin_init_func)(struct lws_context *,
1447 struct lws_plugin_capability *);
1448 typedef int (*lws_plugin_destroy_func)(struct lws_context *);
1450 /** struct lws_plugin */
1452 struct lws_plugin *list; /**< linked list */
1453 #if (UV_VERSION_MAJOR > 0)
1454 uv_lib_t lib; /**< shared library pointer */
1456 void *l; /**< so we can compile on ancient libuv */
1458 char name[64]; /**< name of the plugin */
1459 struct lws_plugin_capability caps; /**< plugin capabilities */
1467 /*! \defgroup generic-sessions plugin: generic-sessions
1468 * \ingroup Protocols-and-Plugins
1470 * ##Plugin Generic-sessions related
1472 * generic-sessions plugin provides a reusable, generic session and login /
1473 * register / forgot password framework including email verification.
1477 #define LWSGS_EMAIL_CONTENT_SIZE 16384
1478 /**< Maximum size of email we might send */
1480 /* SHA-1 binary and hexified versions */
1481 /** typedef struct lwsgw_hash_bin */
1482 typedef struct { unsigned char bin[20]; /**< binary representation of hash */} lwsgw_hash_bin;
1483 /** typedef struct lwsgw_hash */
1484 typedef struct { char id[41]; /**< ascii hex representation of hash */ } lwsgw_hash;
1486 /** enum lwsgs_auth_bits */
1487 enum lwsgs_auth_bits {
1488 LWSGS_AUTH_LOGGED_IN = 1, /**< user is logged in as somebody */
1489 LWSGS_AUTH_ADMIN = 2, /**< logged in as the admin user */
1490 LWSGS_AUTH_VERIFIED = 4, /**< user has verified his email */
1491 LWSGS_AUTH_FORGOT_FLOW = 8, /**< he just completed "forgot password" flow */
1494 /** struct lws_session_info - information about user session status */
1495 struct lws_session_info {
1496 char username[32]; /**< username logged in as, or empty string */
1497 char email[100]; /**< email address associated with login, or empty string */
1498 char ip[72]; /**< ip address session was started from */
1499 unsigned int mask; /**< access rights mask associated with session
1500 * see enum lwsgs_auth_bits */
1501 char session[42]; /**< session id string, usable as opaque uid when not logged in */
1504 /** enum lws_gs_event */
1506 LWSGSE_CREATED, /**< a new user was created */
1507 LWSGSE_DELETED /**< an existing user was deleted */
1510 /** struct lws_gs_event_args */
1511 struct lws_gs_event_args {
1512 enum lws_gs_event event; /**< which event happened */
1513 const char *username; /**< which username the event happened to */
1514 const char *email; /**< the email address of that user */
1520 /*! \defgroup context-and-vhost
1523 * ##Context and Vhost releated functions
1525 * LWS requires that there is one context, in which you may define multiple
1526 * vhosts. Each vhost is a virtual host, with either its own listen port
1527 * or sharing an existing one. Each vhost has its own SSL context that can
1528 * be set up individually or left disabled.
1530 * If you don't care about multiple "site" support, you can ignore it and
1531 * lws will create a single default vhost at context creation time.
1536 * NOTE: These public enums are part of the abi. If you want to add one,
1537 * add it at where specified so existing users are unaffected.
1540 /** enum lws_context_options - context and vhost options */
1541 enum lws_context_options {
1542 LWS_SERVER_OPTION_REQUIRE_VALID_OPENSSL_CLIENT_CERT = (1 << 1) |
1544 /**< (VH) Don't allow the connection unless the client has a
1545 * client cert that we recognize; provides
1546 * LWS_SERVER_OPTION_DO_SSL_GLOBAL_INIT */
1547 LWS_SERVER_OPTION_SKIP_SERVER_CANONICAL_NAME = (1 << 2),
1548 /**< (CTX) Don't try to get the server's hostname */
1549 LWS_SERVER_OPTION_ALLOW_NON_SSL_ON_SSL_PORT = (1 << 3) |
1551 /**< (VH) Allow non-SSL (plaintext) connections on the same
1552 * port as SSL is listening... undermines the security of SSL;
1553 * provides LWS_SERVER_OPTION_DO_SSL_GLOBAL_INIT */
1554 LWS_SERVER_OPTION_LIBEV = (1 << 4),
1555 /**< (CTX) Use libev event loop */
1556 LWS_SERVER_OPTION_DISABLE_IPV6 = (1 << 5),
1557 /**< (VH) Disable IPV6 support */
1558 LWS_SERVER_OPTION_DISABLE_OS_CA_CERTS = (1 << 6),
1559 /**< (VH) Don't load OS CA certs, you will need to load your
1561 LWS_SERVER_OPTION_PEER_CERT_NOT_REQUIRED = (1 << 7),
1562 /**< (VH) Accept connections with no valid Cert (eg, selfsigned) */
1563 LWS_SERVER_OPTION_VALIDATE_UTF8 = (1 << 8),
1564 /**< (VH) Check UT-8 correctness */
1565 LWS_SERVER_OPTION_SSL_ECDH = (1 << 9) |
1567 /**< (VH) initialize ECDH ciphers */
1568 LWS_SERVER_OPTION_LIBUV = (1 << 10),
1569 /**< (CTX) Use libuv event loop */
1570 LWS_SERVER_OPTION_REDIRECT_HTTP_TO_HTTPS = (1 << 11) |
1572 /**< (VH) Use http redirect to force http to https
1573 * (deprecated: use mount redirection) */
1574 LWS_SERVER_OPTION_DO_SSL_GLOBAL_INIT = (1 << 12),
1575 /**< (CTX) Initialize the SSL library at all */
1576 LWS_SERVER_OPTION_EXPLICIT_VHOSTS = (1 << 13),
1577 /**< (CTX) Only create the context when calling context
1578 * create api, implies user code will create its own vhosts */
1579 LWS_SERVER_OPTION_UNIX_SOCK = (1 << 14),
1580 /**< (VH) Use Unix socket */
1581 LWS_SERVER_OPTION_STS = (1 << 15),
1582 /**< (VH) Send Strict Transport Security header, making
1583 * clients subsequently go to https even if user asked for http */
1584 LWS_SERVER_OPTION_IPV6_V6ONLY_MODIFY = (1 << 16),
1585 /**< (VH) Enable LWS_SERVER_OPTION_IPV6_V6ONLY_VALUE to take effect */
1586 LWS_SERVER_OPTION_IPV6_V6ONLY_VALUE = (1 << 17),
1587 /**< (VH) if set, only ipv6 allowed on the vhost */
1588 LWS_SERVER_OPTION_UV_NO_SIGSEGV_SIGFPE_SPIN = (1 << 18),
1589 /**< (CTX) Libuv only: Do not spin on SIGSEGV / SIGFPE. A segfault
1590 * normally makes the lib spin so you can attach a debugger to it
1591 * even if it happened without a debugger in place. You can disable
1592 * that by giving this option.
1594 LWS_SERVER_OPTION_JUST_USE_RAW_ORIGIN = (1 << 19),
1595 /**< For backwards-compatibility reasons, by default
1596 * lws prepends "http://" to the origin you give in the client
1597 * connection info struct. If you give this flag when you create
1598 * the context, only the string you give in the client connect
1599 * info for .origin (if any) will be used directly.
1602 /****** add new things just above ---^ ******/
1605 #define lws_check_opt(c, f) (((c) & (f)) == (f))
1607 /** struct lws_context_creation_info - parameters to create context and /or vhost with
1609 * This is also used to create vhosts.... if LWS_SERVER_OPTION_EXPLICIT_VHOSTS
1610 * is not given, then for backwards compatibility one vhost is created at
1611 * context-creation time using the info from this struct.
1613 * If LWS_SERVER_OPTION_EXPLICIT_VHOSTS is given, then no vhosts are created
1614 * at the same time as the context, they are expected to be created afterwards.
1616 struct lws_context_creation_info {
1618 /**< VHOST: Port to listen on. Use CONTEXT_PORT_NO_LISTEN to suppress
1619 * listening for a client. Use CONTEXT_PORT_NO_LISTEN_SERVER if you are
1620 * writing a server but you are using \ref sock-adopt instead of the
1621 * built-in listener */
1623 /**< VHOST: NULL to bind the listen socket to all interfaces, or the
1624 * interface name, eg, "eth2"
1625 * If options specifies LWS_SERVER_OPTION_UNIX_SOCK, this member is
1626 * the pathname of a UNIX domain socket. you can use the UNIX domain
1627 * sockets in abstract namespace, by prepending an at symbol to the
1629 const struct lws_protocols *protocols;
1630 /**< VHOST: Array of structures listing supported protocols and a protocol-
1631 * specific callback for each one. The list is ended with an
1632 * entry that has a NULL callback pointer. */
1633 const struct lws_extension *extensions;
1634 /**< VHOST: NULL or array of lws_extension structs listing the
1635 * extensions this context supports. */
1636 const struct lws_token_limits *token_limits;
1637 /**< CONTEXT: NULL or struct lws_token_limits pointer which is initialized
1638 * with a token length limit for each possible WSI_TOKEN_ */
1639 const char *ssl_private_key_password;
1640 /**< VHOST: NULL or the passphrase needed for the private key */
1641 const char *ssl_cert_filepath;
1642 /**< VHOST: If libwebsockets was compiled to use ssl, and you want
1643 * to listen using SSL, set to the filepath to fetch the
1644 * server cert from, otherwise NULL for unencrypted */
1645 const char *ssl_private_key_filepath;
1646 /**< VHOST: filepath to private key if wanting SSL mode;
1647 * if this is set to NULL but sll_cert_filepath is set, the
1648 * OPENSSL_CONTEXT_REQUIRES_PRIVATE_KEY callback is called
1649 * to allow setting of the private key directly via openSSL
1651 const char *ssl_ca_filepath;
1652 /**< VHOST: CA certificate filepath or NULL */
1653 const char *ssl_cipher_list;
1654 /**< VHOST: List of valid ciphers to use (eg,
1655 * "RC4-MD5:RC4-SHA:AES128-SHA:AES256-SHA:HIGH:!DSS:!aNULL"
1656 * or you can leave it as NULL to get "DEFAULT" */
1657 const char *http_proxy_address;
1658 /**< VHOST: If non-NULL, attempts to proxy via the given address.
1659 * If proxy auth is required, use format "username:password\@server:port" */
1660 unsigned int http_proxy_port;
1661 /**< VHOST: If http_proxy_address was non-NULL, uses this port */
1663 /**< CONTEXT: group id to change to after setting listen socket, or -1. */
1665 /**< CONTEXT: user id to change to after setting listen socket, or -1. */
1666 unsigned int options;
1667 /**< VHOST + CONTEXT: 0, or LWS_SERVER_OPTION_... bitfields */
1669 /**< CONTEXT: optional user pointer that can be recovered via the context
1670 * pointer using lws_context_user */
1672 /**< CONTEXT: 0 for no TCP keepalive, otherwise apply this keepalive
1673 * timeout to all libwebsocket sockets, client or server */
1675 /**< CONTEXT: if ka_time was nonzero, after the timeout expires how many
1676 * times to try to get a response from the peer before giving up
1677 * and killing the connection */
1679 /**< CONTEXT: if ka_time was nonzero, how long to wait before each ka_probes
1681 #ifdef LWS_OPENSSL_SUPPORT
1682 SSL_CTX *provided_client_ssl_ctx;
1683 /**< CONTEXT: If non-null, swap out libwebsockets ssl
1684 * implementation for the one provided by provided_ssl_ctx.
1685 * Libwebsockets no longer is responsible for freeing the context
1686 * if this option is selected. */
1687 #else /* maintain structure layout either way */
1688 void *provided_client_ssl_ctx; /**< dummy if ssl disabled */
1691 short max_http_header_data;
1692 /**< CONTEXT: The max amount of header payload that can be handled
1693 * in an http request (unrecognized header payload is dropped) */
1694 short max_http_header_pool;
1695 /**< CONTEXT: The max number of connections with http headers that
1696 * can be processed simultaneously (the corresponding memory is
1697 * allocated for the lifetime of the context). If the pool is
1698 * busy new incoming connections must wait for accept until one
1701 unsigned int count_threads;
1702 /**< CONTEXT: how many contexts to create in an array, 0 = 1 */
1703 unsigned int fd_limit_per_thread;
1704 /**< CONTEXT: nonzero means restrict each service thread to this
1705 * many fds, 0 means the default which is divide the process fd
1706 * limit by the number of threads. */
1707 unsigned int timeout_secs;
1708 /**< VHOST: various processes involving network roundtrips in the
1709 * library are protected from hanging forever by timeouts. If
1710 * nonzero, this member lets you set the timeout used in seconds.
1711 * Otherwise a default timeout is used. */
1712 const char *ecdh_curve;
1713 /**< VHOST: if NULL, defaults to initializing server with "prime256v1" */
1714 const char *vhost_name;
1715 /**< VHOST: name of vhost, must match external DNS name used to
1716 * access the site, like "warmcat.com" as it's used to match
1717 * Host: header and / or SNI name for SSL. */
1718 const char * const *plugin_dirs;
1719 /**< CONTEXT: NULL, or NULL-terminated array of directories to
1720 * scan for lws protocol plugins at context creation time */
1721 const struct lws_protocol_vhost_options *pvo;
1722 /**< VHOST: pointer to optional linked list of per-vhost
1723 * options made accessible to protocols */
1724 int keepalive_timeout;
1725 /**< VHOST: (default = 0 = 60s) seconds to allow remote
1726 * client to hold on to an idle HTTP/1.1 connection */
1727 const char *log_filepath;
1728 /**< VHOST: filepath to append logs to... this is opened before
1729 * any dropping of initial privileges */
1730 const struct lws_http_mount *mounts;
1731 /**< VHOST: optional linked list of mounts for this vhost */
1732 const char *server_string;
1733 /**< CONTEXT: string used in HTTP headers to identify server
1734 * software, if NULL, "libwebsockets". */
1735 unsigned int pt_serv_buf_size;
1736 /**< CONTEXT: 0 = default of 4096. This buffer is used by
1737 * various service related features including file serving, it
1738 * defines the max chunk of file that can be sent at once.
1739 * At the risk of lws having to buffer failed large sends, it
1740 * can be increased to, eg, 128KiB to improve throughput. */
1741 unsigned int max_http_header_data2;
1742 /**< CONTEXT: if max_http_header_data is 0 and this
1743 * is nonzero, this will be used in place of the default. It's
1744 * like this for compatibility with the original short version,
1745 * this is unsigned int length. */
1746 long ssl_options_set;
1747 /**< VHOST: Any bits set here will be set as SSL options */
1748 long ssl_options_clear;
1749 /**< VHOST: Any bits set here will be cleared as SSL options */
1750 unsigned short ws_ping_pong_interval;
1751 /**< CONTEXT: 0 for none, else interval in seconds between sending
1752 * PINGs on idle websocket connections. When the PING is sent,
1753 * the PONG must come within the normal timeout_secs timeout period
1754 * or the connection will be dropped.
1755 * Any RX or TX traffic on the connection restarts the interval timer,
1756 * so a connection which always sends or receives something at intervals
1757 * less than the interval given here will never send PINGs / expect
1758 * PONGs. Conversely as soon as the ws connection is established, an
1759 * idle connection will do the PING / PONG roundtrip as soon as
1760 * ws_ping_pong_interval seconds has passed without traffic
1762 const struct lws_protocol_vhost_options *headers;
1763 /**< VHOST: pointer to optional linked list of per-vhost
1764 * canned headers that are added to server responses */
1766 const struct lws_protocol_vhost_options *reject_service_keywords;
1767 /**< CONTEXT: Optional list of keywords and rejection codes + text.
1769 * The keywords are checked for existing in the user agent string.
1771 * Eg, "badrobot" "404 Not Found"
1773 void *external_baggage_free_on_destroy;
1774 /**< CONTEXT: NULL, or pointer to something externally malloc'd, that
1775 * should be freed when the context is destroyed. This allows you to
1776 * automatically sync the freeing action to the context destruction
1777 * action, so there is no need for an external free() if the context
1778 * succeeded to create.
1781 #ifdef LWS_OPENSSL_SUPPORT
1782 /**< CONTEXT: NULL or struct lws_token_limits pointer which is initialized
1783 * with a token length limit for each possible WSI_TOKEN_ */
1784 const char *client_ssl_private_key_password;
1785 /**< VHOST: NULL or the passphrase needed for the private key */
1786 const char *client_ssl_cert_filepath;
1787 /**< VHOST: If libwebsockets was compiled to use ssl, and you want
1788 * to listen using SSL, set to the filepath to fetch the
1789 * server cert from, otherwise NULL for unencrypted */
1790 const char *client_ssl_private_key_filepath;
1791 /**< VHOST: filepath to private key if wanting SSL mode;
1792 * if this is set to NULL but sll_cert_filepath is set, the
1793 * OPENSSL_CONTEXT_REQUIRES_PRIVATE_KEY callback is called
1794 * to allow setting of the private key directly via openSSL
1796 const char *client_ssl_ca_filepath;
1797 /**< VHOST: CA certificate filepath or NULL */
1798 const char *client_ssl_cipher_list;
1799 /**< VHOST: List of valid ciphers to use (eg,
1800 * "RC4-MD5:RC4-SHA:AES128-SHA:AES256-SHA:HIGH:!DSS:!aNULL"
1801 * or you can leave it as NULL to get "DEFAULT" */
1804 /* Add new things just above here ---^
1805 * This is part of the ABI, don't needlessly break compatibility
1807 * The below is to ensure later library versions with new
1808 * members added above will see 0 (default) even if the app
1809 * was not built against the newer headers.
1812 void *_unused[8]; /**< dummy */
1816 * lws_create_context() - Create the websocket handler
1817 * \param info: pointer to struct with parameters
1819 * This function creates the listening socket (if serving) and takes care
1820 * of all initialization in one step.
1822 * If option LWS_SERVER_OPTION_EXPLICIT_VHOSTS is given, no vhost is
1823 * created; you're expected to create your own vhosts afterwards using
1824 * lws_create_vhost(). Otherwise a vhost named "default" is also created
1825 * using the information in the vhost-related members, for compatibility.
1827 * After initialization, it returns a struct lws_context * that
1828 * represents this server. After calling, user code needs to take care
1829 * of calling lws_service() with the context pointer to get the
1830 * server's sockets serviced. This must be done in the same process
1831 * context as the initialization call.
1833 * The protocol callback functions are called for a handful of events
1834 * including http requests coming in, websocket connections becoming
1835 * established, and data arriving; it's also called periodically to allow
1836 * async transmission.
1838 * HTTP requests are sent always to the FIRST protocol in protocol, since
1839 * at that time websocket protocol has not been negotiated. Other
1840 * protocols after the first one never see any HTTP callback activity.
1842 * The server created is a simple http server by default; part of the
1843 * websocket standard is upgrading this http connection to a websocket one.
1845 * This allows the same server to provide files like scripts and favicon /
1846 * images or whatever over http and dynamic data over websockets all in
1847 * one place; they're all handled in the user callback.
1849 LWS_VISIBLE LWS_EXTERN struct lws_context *
1850 lws_create_context(struct lws_context_creation_info *info);
1853 * lws_context_destroy() - Destroy the websocket context
1854 * \param context: Websocket context
1856 * This function closes any active connections and then frees the
1857 * context. After calling this, any further use of the context is
1860 LWS_VISIBLE LWS_EXTERN void
1861 lws_context_destroy(struct lws_context *context);
1863 LWS_VISIBLE LWS_EXTERN void
1864 lws_context_destroy2(struct lws_context *context);
1866 typedef int (*lws_reload_func)(void);
1869 * lws_context_deprecate() - Deprecate the websocket context
1870 * \param context: Websocket context
1872 * This function is used on an existing context before superceding it
1873 * with a new context.
1875 * It closes any listen sockets in the context, so new connections are
1878 * And it marks the context to be deleted when the number of active
1879 * connections into it falls to zero.
1881 * Otherwise if you attach the deprecated context to the replacement
1882 * context when it has been created using lws_context_attach_deprecated()
1883 * both any deprecated and the new context will service their connections.
1885 * This is aimed at allowing seamless configuration reloads.
1887 * The callback cb will be called after the listen sockets are actually
1888 * closed and may be reopened. In the callback the new context should be
1889 * configured and created. (With libuv, socket close happens async after
1890 * more loop events).
1892 LWS_VISIBLE LWS_EXTERN void
1893 lws_context_deprecate(struct lws_context *context, lws_reload_func cb);
1895 LWS_VISIBLE LWS_EXTERN int
1896 lws_context_is_deprecated(struct lws_context *context);
1899 * lws_set_proxy() - Setups proxy to lws_context.
1900 * \param vhost: pointer to struct lws_vhost you want set proxy for
1901 * \param proxy: pointer to c string containing proxy in format address:port
1903 * Returns 0 if proxy string was parsed and proxy was setup.
1904 * Returns -1 if proxy is NULL or has incorrect format.
1906 * This is only required if your OS does not provide the http_proxy
1907 * environment variable (eg, OSX)
1909 * IMPORTANT! You should call this function right after creation of the
1910 * lws_context and before call to connect. If you call this
1911 * function after connect behavior is undefined.
1912 * This function will override proxy settings made on lws_context
1913 * creation with genenv() call.
1915 LWS_VISIBLE LWS_EXTERN int
1916 lws_set_proxy(struct lws_vhost *vhost, const char *proxy);
1922 * lws_create_vhost() - Create a vhost (virtual server context)
1923 * \param context: pointer to result of lws_create_context()
1924 * \param info: pointer to struct with parameters
1926 * This function creates a virtual server (vhost) using the vhost-related
1927 * members of the info struct. You can create many vhosts inside one context
1928 * if you created the context with the option LWS_SERVER_OPTION_EXPLICIT_VHOSTS
1930 LWS_EXTERN LWS_VISIBLE struct lws_vhost *
1931 lws_create_vhost(struct lws_context *context,
1932 struct lws_context_creation_info *info);
1935 * lwsws_get_config_globals() - Parse a JSON server config file
1936 * \param info: pointer to struct with parameters
1937 * \param d: filepath of the config file
1938 * \param config_strings: storage for the config strings extracted from JSON,
1939 * the pointer is incremented as strings are stored
1940 * \param len: pointer to the remaining length left in config_strings
1941 * the value is decremented as strings are stored
1943 * This function prepares a n lws_context_creation_info struct with global
1944 * settings from a file d.
1946 * Requires CMake option LWS_WITH_LEJP_CONF to have been enabled
1948 LWS_VISIBLE LWS_EXTERN int
1949 lwsws_get_config_globals(struct lws_context_creation_info *info, const char *d,
1950 char **config_strings, int *len);
1953 * lwsws_get_config_vhosts() - Create vhosts from a JSON server config file
1954 * \param context: pointer to result of lws_create_context()
1955 * \param info: pointer to struct with parameters
1956 * \param d: filepath of the config file
1957 * \param config_strings: storage for the config strings extracted from JSON,
1958 * the pointer is incremented as strings are stored
1959 * \param len: pointer to the remaining length left in config_strings
1960 * the value is decremented as strings are stored
1962 * This function creates vhosts into a context according to the settings in
1963 *JSON files found in directory d.
1965 * Requires CMake option LWS_WITH_LEJP_CONF to have been enabled
1967 LWS_VISIBLE LWS_EXTERN int
1968 lwsws_get_config_vhosts(struct lws_context *context,
1969 struct lws_context_creation_info *info, const char *d,
1970 char **config_strings, int *len);
1972 /** lws_vhost_get() - \deprecated deprecated: use lws_get_vhost() */
1973 LWS_VISIBLE LWS_EXTERN struct lws_vhost *
1974 lws_vhost_get(struct lws *wsi) LWS_WARN_DEPRECATED;
1977 * lws_get_vhost() - return the vhost a wsi belongs to
1979 * \param wsi: which connection
1981 LWS_VISIBLE LWS_EXTERN struct lws_vhost *
1982 lws_get_vhost(struct lws *wsi);
1985 * lws_json_dump_vhost() - describe vhost state and stats in JSON
1987 * \param vh: the vhost
1988 * \param buf: buffer to fill with JSON
1989 * \param len: max length of buf
1991 LWS_VISIBLE LWS_EXTERN int
1992 lws_json_dump_vhost(const struct lws_vhost *vh, char *buf, int len);
1995 * lws_json_dump_context() - describe context state and stats in JSON
1997 * \param context: the context
1998 * \param buf: buffer to fill with JSON
1999 * \param len: max length of buf
2001 LWS_VISIBLE LWS_EXTERN int
2002 lws_json_dump_context(const struct lws_context *context, char *buf, int len,
2006 * lws_context_user() - get the user data associated with the context
2007 * \param context: Websocket context
2009 * This returns the optional user allocation that can be attached to
2010 * the context the sockets live in at context_create time. It's a way
2011 * to let all sockets serviced in the same context share data without
2012 * using globals statics in the user code.
2014 LWS_VISIBLE LWS_EXTERN void *
2015 lws_context_user(struct lws_context *context);
2017 /*! \defgroup vhost-mounts Vhost mounts and options
2018 * \ingroup context-and-vhost-creation
2020 * ##Vhost mounts and options
2023 /** struct lws_protocol_vhost_options - linked list of per-vhost protocol
2024 * name=value options
2026 * This provides a general way to attach a linked-list of name=value pairs,
2027 * which can also have an optional child link-list using the options member.
2029 struct lws_protocol_vhost_options {
2030 const struct lws_protocol_vhost_options *next; /**< linked list */
2031 const struct lws_protocol_vhost_options *options; /**< child linked-list of more options for this node */
2032 const char *name; /**< name of name=value pair */
2033 const char *value; /**< value of name=value pair */
2036 /** enum lws_mount_protocols
2037 * This specifies the mount protocol for a mountpoint, whether it is to be
2038 * served from a filesystem, or it is a cgi etc.
2040 enum lws_mount_protocols {
2041 LWSMPRO_HTTP = 0, /**< not supported yet */
2042 LWSMPRO_HTTPS = 1, /**< not supported yet */
2043 LWSMPRO_FILE = 2, /**< serve from filesystem directory */
2044 LWSMPRO_CGI = 3, /**< pass to CGI to handle */
2045 LWSMPRO_REDIR_HTTP = 4, /**< redirect to http:// url */
2046 LWSMPRO_REDIR_HTTPS = 5, /**< redirect to https:// url */
2047 LWSMPRO_CALLBACK = 6, /**< hand by named protocol's callback */
2050 /** struct lws_http_mount
2052 * arguments for mounting something in a vhost's url namespace
2054 struct lws_http_mount {
2055 const struct lws_http_mount *mount_next;
2056 /**< pointer to next struct lws_http_mount */
2057 const char *mountpoint;
2058 /**< mountpoint in http pathspace, eg, "/" */
2060 /**< path to be mounted, eg, "/var/www/warmcat.com" */
2062 /**< default target, eg, "index.html" */
2063 const char *protocol;
2064 /**<"protocol-name" to handle mount */
2066 const struct lws_protocol_vhost_options *cgienv;
2067 /**< optional linked-list of cgi options. These are created
2068 * as environment variables for the cgi process
2070 const struct lws_protocol_vhost_options *extra_mimetypes;
2071 /**< optional linked-list of mimetype mappings */
2072 const struct lws_protocol_vhost_options *interpret;
2073 /**< optional linked-list of files to be interpreted */
2076 /**< seconds cgi is allowed to live, if cgi://mount type */
2078 /**< max-age for reuse of client cache of files, seconds */
2079 unsigned int auth_mask;
2080 /**< bits set here must be set for authorized client session */
2082 unsigned int cache_reusable:1; /**< set if client cache may reuse this */
2083 unsigned int cache_revalidate:1; /**< set if client cache should revalidate on use */
2084 unsigned int cache_intermediaries:1; /**< set if intermediaries are allowed to cache */
2086 unsigned char origin_protocol; /**< one of enum lws_mount_protocols */
2087 unsigned char mountpoint_len; /**< length of mountpoint string */
2089 const char *basic_auth_login_file;
2090 /**<NULL, or filepath to use to check basic auth logins against */
2092 /* Add new things just above here ---^
2093 * This is part of the ABI, don't needlessly break compatibility
2095 * The below is to ensure later library versions with new
2096 * members added above will see 0 (default) even if the app
2097 * was not built against the newer headers.
2100 void *_unused[2]; /**< dummy */
2105 /*! \defgroup client
2108 * ##Client releated functions
2112 /** enum lws_client_connect_ssl_connection_flags - flags that may be used
2113 * with struct lws_client_connect_info ssl_connection member to control if
2114 * and how SSL checks apply to the client connection being created
2117 enum lws_client_connect_ssl_connection_flags {
2118 LCCSCF_USE_SSL = (1 << 0),
2119 LCCSCF_ALLOW_SELFSIGNED = (1 << 1),
2120 LCCSCF_SKIP_SERVER_CERT_HOSTNAME_CHECK = (1 << 2),
2121 LCCSCF_ALLOW_EXPIRED = (1 << 3)
2124 /** struct lws_client_connect_info - parameters to connect with when using
2125 * lws_client_connect_via_info() */
2127 struct lws_client_connect_info {
2128 struct lws_context *context;
2129 /**< lws context to create connection in */
2130 const char *address;
2131 /**< remote address to connect to */
2133 /**< remote port to connect to */
2135 /**< nonzero for ssl */
2139 /**< content of host header */
2141 /**< content of origin header */
2142 const char *protocol;
2143 /**< list of ws protocols we could accept */
2144 int ietf_version_or_minus_one;
2145 /**< deprecated: currently leave at 0 or -1 */
2147 /**< if non-NULL, use this as wsi user_data instead of malloc it */
2148 const void *client_exts;
2149 /**< UNUSED... provide in info.extensions at context creation time */
2151 /**< if non-NULL, do this http method instead of ws[s] upgrade.
2152 * use "GET" to be a simple http client connection */
2153 struct lws *parent_wsi;
2154 /**< if another wsi is responsible for this connection, give it here.
2155 * this is used to make sure if the parent closes so do any
2156 * child connections first. */
2157 const char *uri_replace_from;
2158 /**< if non-NULL, when this string is found in URIs in
2159 * text/html content-encoding, it's replaced with uri_replace_to */
2160 const char *uri_replace_to;
2161 /**< see uri_replace_from */
2162 struct lws_vhost *vhost;
2163 /**< vhost to bind to (used to determine related SSL_CTX) */
2165 /**< if not NULL, store the new wsi here early in the connection
2166 * process. Although we return the new wsi, the call to create the
2167 * client connection does progress the connection somewhat and may
2168 * meet an error that will result in the connection being scrubbed and
2169 * NULL returned. While the wsi exists though, he may process a
2170 * callback like CLIENT_CONNECTION_ERROR with his wsi: this gives the
2171 * user callback a way to identify which wsi it is that faced the error
2172 * even before the new wsi is returned and even if ultimately no wsi
2176 /* Add new things just above here ---^
2177 * This is part of the ABI, don't needlessly break compatibility
2179 * The below is to ensure later library versions with new
2180 * members added above will see 0 (default) even if the app
2181 * was not built against the newer headers.
2184 void *_unused[4]; /**< dummy */
2188 * lws_client_connect_via_info() - Connect to another websocket server
2189 * \param ccinfo: pointer to lws_client_connect_info struct
2191 * This function creates a connection to a remote server using the
2192 * information provided in ccinfo.
2194 LWS_VISIBLE LWS_EXTERN struct lws *
2195 lws_client_connect_via_info(struct lws_client_connect_info * ccinfo);
2198 * lws_client_connect() - Connect to another websocket server
2199 * \deprecated DEPRECATED use lws_client_connect_via_info
2200 * \param clients: Websocket context
2201 * \param address: Remote server address, eg, "myserver.com"
2202 * \param port: Port to connect to on the remote server, eg, 80
2203 * \param ssl_connection: 0 = ws://, 1 = wss:// encrypted, 2 = wss:// allow self
2205 * \param path: Websocket path on server
2206 * \param host: Hostname on server
2207 * \param origin: Socket origin name
2208 * \param protocol: Comma-separated list of protocols being asked for from
2209 * the server, or just one. The server will pick the one it
2210 * likes best. If you don't want to specify a protocol, which is
2211 * legal, use NULL here.
2212 * \param ietf_version_or_minus_one: -1 to ask to connect using the default, latest
2213 * protocol supported, or the specific protocol ordinal
2215 * This function creates a connection to a remote server
2217 /* deprecated, use lws_client_connect_via_info() */
2218 LWS_VISIBLE LWS_EXTERN struct lws * LWS_WARN_UNUSED_RESULT
2219 lws_client_connect(struct lws_context *clients, const char *address,
2220 int port, int ssl_connection, const char *path,
2221 const char *host, const char *origin, const char *protocol,
2222 int ietf_version_or_minus_one) LWS_WARN_DEPRECATED;
2223 /* deprecated, use lws_client_connect_via_info() */
2225 * lws_client_connect_extended() - Connect to another websocket server
2226 * \deprecated DEPRECATED use lws_client_connect_via_info
2227 * \param clients: Websocket context
2228 * \param address: Remote server address, eg, "myserver.com"
2229 * \param port: Port to connect to on the remote server, eg, 80
2230 * \param ssl_connection: 0 = ws://, 1 = wss:// encrypted, 2 = wss:// allow self
2232 * \param path: Websocket path on server
2233 * \param host: Hostname on server
2234 * \param origin: Socket origin name
2235 * \param protocol: Comma-separated list of protocols being asked for from
2236 * the server, or just one. The server will pick the one it
2238 * \param ietf_version_or_minus_one: -1 to ask to connect using the default, latest
2239 * protocol supported, or the specific protocol ordinal
2240 * \param userdata: Pre-allocated user data
2242 * This function creates a connection to a remote server
2244 LWS_VISIBLE LWS_EXTERN struct lws * LWS_WARN_UNUSED_RESULT
2245 lws_client_connect_extended(struct lws_context *clients, const char *address,
2246 int port, int ssl_connection, const char *path,
2247 const char *host, const char *origin,
2248 const char *protocol, int ietf_version_or_minus_one,
2249 void *userdata) LWS_WARN_DEPRECATED;
2252 * lws_init_vhost_client_ssl() - also enable client SSL on an existing vhost
2254 * \param info: client ssl related info
2255 * \param vhost: which vhost to initialize client ssl operations on
2257 * You only need to call this if you plan on using SSL client connections on
2258 * the vhost. For non-SSL client connections, it's not necessary to call this.
2260 * The following members of info are used during the call
2262 * - options must have LWS_SERVER_OPTION_DO_SSL_GLOBAL_INIT set,
2263 * otherwise the call does nothing
2264 * - provided_client_ssl_ctx must be NULL to get a generated client
2265 * ssl context, otherwise you can pass a prepared one in by setting it
2266 * - ssl_cipher_list may be NULL or set to the client valid cipher list
2267 * - ssl_ca_filepath may be NULL or client cert filepath
2268 * - ssl_cert_filepath may be NULL or client cert filepath
2269 * - ssl_private_key_filepath may be NULL or client cert private key
2271 * You must create your vhost explicitly if you want to use this, so you have
2272 * a pointer to the vhost. Create the context first with the option flag
2273 * LWS_SERVER_OPTION_EXPLICIT_VHOSTS and then call lws_create_vhost() with
2274 * the same info struct.
2276 LWS_VISIBLE LWS_EXTERN int
2277 lws_init_vhost_client_ssl(const struct lws_context_creation_info *info,
2278 struct lws_vhost *vhost);
2281 * lws_http_client_read() - consume waiting received http client data
2283 * \param wsi: client connection
2284 * \param buf: pointer to buffer pointer - fill with pointer to your buffer
2285 * \param len: pointer to chunk length - fill with max length of buffer
2287 * This is called when the user code is notified client http data has arrived.
2288 * The user code may choose to delay calling it to consume the data, for example
2289 * waiting until an onward connection is writeable.
2291 * For non-chunked connections, up to len bytes of buf are filled with the
2292 * received content. len is set to the actual amount filled before return.
2294 * For chunked connections, the linear buffer content contains the chunking
2295 * headers and it cannot be passed in one lump. Instead, this function will
2296 * call back LWS_CALLBACK_RECEIVE_CLIENT_HTTP_READ with in pointing to the
2297 * chunk start and len set to the chunk length. There will be as many calls
2298 * as there are chunks or partial chunks in the buffer.
2300 LWS_VISIBLE LWS_EXTERN int
2301 lws_http_client_read(struct lws *wsi, char **buf, int *len);
2304 * lws_http_client_http_response() - get last HTTP response code
2306 * \param wsi: client connection
2308 * Returns the last server response code, eg, 200 for client http connections.
2310 LWS_VISIBLE LWS_EXTERN unsigned int
2311 lws_http_client_http_response(struct lws *wsi);
2313 LWS_VISIBLE LWS_EXTERN void
2314 lws_client_http_body_pending(struct lws *wsi, int something_left_to_send);
2317 * lws_client_http_body_pending() - control if client connection neeeds to send body
2319 * \param wsi: client connection
2320 * \param something_left_to_send: nonzero if need to send more body, 0 (default)
2321 * if nothing more to send
2323 * If you will send payload data with your HTTP client connection, eg, for POST,
2324 * when you set the related http headers in
2325 * LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER callback you should also call
2326 * this API with something_left_to_send nonzero, and call
2327 * lws_callback_on_writable(wsi);
2329 * After sending the headers, lws will call your callback with
2330 * LWS_CALLBACK_CLIENT_HTTP_WRITEABLE reason when writable. You can send the
2331 * next part of the http body payload, calling lws_callback_on_writable(wsi);
2332 * if there is more to come, or lws_client_http_body_pending(wsi, 0); to
2333 * let lws know the last part is sent and the connection can move on.
2338 /** \defgroup service Built-in service loop entry
2340 * ##Built-in service loop entry
2342 * If you're not using libev / libuv, these apis are needed to enter the poll()
2343 * wait in lws and service any connections with pending events.
2348 * lws_service() - Service any pending websocket activity
2349 * \param context: Websocket context
2350 * \param timeout_ms: Timeout for poll; 0 means return immediately if nothing needed
2351 * service otherwise block and service immediately, returning
2352 * after the timeout if nothing needed service.
2354 * This function deals with any pending websocket traffic, for three
2355 * kinds of event. It handles these events on both server and client
2356 * types of connection the same.
2358 * 1) Accept new connections to our context's server
2360 * 2) Call the receive callback for incoming frame data received by
2361 * server or client connections.
2363 * You need to call this service function periodically to all the above
2364 * functions to happen; if your application is single-threaded you can
2365 * just call it in your main event loop.
2367 * Alternatively you can fork a new process that asynchronously handles
2368 * calling this service in a loop. In that case you are happy if this
2369 * call blocks your thread until it needs to take care of something and
2370 * would call it with a large nonzero timeout. Your loop then takes no
2371 * CPU while there is nothing happening.
2373 * If you are calling it in a single-threaded app, you don't want it to
2374 * wait around blocking other things in your loop from happening, so you
2375 * would call it with a timeout_ms of 0, so it returns immediately if
2376 * nothing is pending, or as soon as it services whatever was pending.
2378 LWS_VISIBLE LWS_EXTERN int
2379 lws_service(struct lws_context *context, int timeout_ms);
2382 * lws_service() - Service any pending websocket activity
2384 * \param context: Websocket context
2385 * \param timeout_ms: Timeout for poll; 0 means return immediately if nothing needed
2386 * service otherwise block and service immediately, returning
2387 * after the timeout if nothing needed service.
2389 * Same as lws_service(), but for a specific thread service index. Only needed
2390 * if you are spawning multiple service threads.
2392 LWS_VISIBLE LWS_EXTERN int
2393 lws_service_tsi(struct lws_context *context, int timeout_ms, int tsi);
2396 * lws_cancel_service_pt() - Cancel servicing of pending socket activity
2398 * \param wsi: Cancel service on the thread this wsi is serviced by
2400 * This function lets a call to lws_service() waiting for a timeout
2401 * immediately return.
2403 * It works by creating a phony event and then swallowing it silently.
2405 * The reason it may be needed is when waiting in poll(), changes to
2406 * the event masks are ignored by the OS until poll() is reentered. This
2407 * lets you halt the poll() wait and make the reentry happen immediately
2408 * instead of having the wait out the rest of the poll timeout.
2410 LWS_VISIBLE LWS_EXTERN void
2411 lws_cancel_service_pt(struct lws *wsi);
2414 * lws_cancel_service() - Cancel wait for new pending socket activity
2415 * \param context: Websocket context
2417 * This function let a call to lws_service() waiting for a timeout
2418 * immediately return.
2420 * What it basically does is provide a fake event that will be swallowed,
2421 * so the wait in poll() is ended. That's useful because poll() doesn't
2422 * attend to changes in POLLIN/OUT/ERR until it re-enters the wait.
2424 LWS_VISIBLE LWS_EXTERN void
2425 lws_cancel_service(struct lws_context *context);
2428 * lws_service_fd() - Service polled socket with something waiting
2429 * \param context: Websocket context
2430 * \param pollfd: The pollfd entry describing the socket fd and which events
2431 * happened, or NULL to tell lws to do only timeout servicing.
2433 * This function takes a pollfd that has POLLIN or POLLOUT activity and
2434 * services it according to the state of the associated
2437 * The one call deals with all "service" that might happen on a socket
2438 * including listen accepts, http files as well as websocket protocol.
2440 * If a pollfd says it has something, you can just pass it to
2441 * lws_service_fd() whether it is a socket handled by lws or not.
2442 * If it sees it is a lws socket, the traffic will be handled and
2443 * pollfd->revents will be zeroed now.
2445 * If the socket is foreign to lws, it leaves revents alone. So you can
2446 * see if you should service yourself by checking the pollfd revents
2447 * after letting lws try to service it.
2449 * You should also call this with pollfd = NULL to just allow the
2450 * once-per-second global timeout checks; if less than a second since the last
2451 * check it returns immediately then.
2453 LWS_VISIBLE LWS_EXTERN int
2454 lws_service_fd(struct lws_context *context, struct lws_pollfd *pollfd);
2457 * lws_service_fd_tsi() - Service polled socket in specific service thread
2458 * \param context: Websocket context
2459 * \param pollfd: The pollfd entry describing the socket fd and which events
2461 * \param tsi: thread service index
2463 * Same as lws_service_fd() but used with multiple service threads
2465 LWS_VISIBLE LWS_EXTERN int
2466 lws_service_fd_tsi(struct lws_context *context, struct lws_pollfd *pollfd,
2470 * lws_service_adjust_timeout() - Check for any connection needing forced service
2471 * \param context: Websocket context
2472 * \param timeout_ms: The original poll timeout value. You can just set this
2473 * to 1 if you don't really have a poll timeout.
2474 * \param tsi: thread service index
2476 * Under some conditions connections may need service even though there is no
2477 * pending network action on them, this is "forced service". For default
2478 * poll() and libuv / libev, the library takes care of calling this and
2479 * dealing with it for you. But for external poll() integration, you need
2480 * access to the apis.
2482 * If anybody needs "forced service", returned timeout is zero. In that case,
2483 * you can call lws_service_tsi() with a timeout of -1 to only service
2484 * guys who need forced service.
2486 LWS_VISIBLE LWS_EXTERN int
2487 lws_service_adjust_timeout(struct lws_context *context, int timeout_ms, int tsi);
2489 /* Backwards compatibility */
2490 #define lws_plat_service_tsi lws_service_tsi
2494 /*! \defgroup http HTTP
2496 Modules related to handling HTTP
2500 /*! \defgroup httpft HTTP File transfer
2503 APIs for sending local files in response to HTTP requests
2508 * lws_get_mimetype() - Determine mimetype to use from filename
2510 * \param file: filename
2511 * \param m: NULL, or mount context
2513 * This uses a canned list of known filetypes first, if no match and m is
2514 * non-NULL, then tries a list of per-mount file suffix to mimtype mappings.
2516 * Returns either NULL or a pointer to the mimetype matching the file.
2518 LWS_VISIBLE LWS_EXTERN const char *
2519 lws_get_mimetype(const char *file, const struct lws_http_mount *m);
2522 * lws_serve_http_file() - Send a file back to the client using http
2523 * \param wsi: Websocket instance (available from user callback)
2524 * \param file: The file to issue over http
2525 * \param content_type: The http content type, eg, text/html
2526 * \param other_headers: NULL or pointer to header string
2527 * \param other_headers_len: length of the other headers if non-NULL
2529 * This function is intended to be called from the callback in response
2530 * to http requests from the client. It allows the callback to issue
2531 * local files down the http link in a single step.
2533 * Returning <0 indicates error and the wsi should be closed. Returning
2534 * >0 indicates the file was completely sent and
2535 * lws_http_transaction_completed() called on the wsi (and close if != 0)
2536 * ==0 indicates the file transfer is started and needs more service later,
2537 * the wsi should be left alone.
2539 LWS_VISIBLE LWS_EXTERN int
2540 lws_serve_http_file(struct lws *wsi, const char *file, const char *content_type,
2541 const char *other_headers, int other_headers_len);
2542 LWS_VISIBLE LWS_EXTERN int
2543 lws_serve_http_file_fragment(struct lws *wsi);
2546 /*! \defgroup html-chunked-substitution HTML Chunked Substitution
2549 * ##HTML chunked Substitution
2551 * APIs for receiving chunks of text, replacing a set of variable names via
2552 * a callback, and then prepending and appending HTML chunked encoding
2558 HTTP_STATUS_OK = 200,
2559 HTTP_STATUS_NO_CONTENT = 204,
2560 HTTP_STATUS_PARTIAL_CONTENT = 206,
2562 HTTP_STATUS_MOVED_PERMANENTLY = 301,
2563 HTTP_STATUS_FOUND = 302,
2564 HTTP_STATUS_SEE_OTHER = 303,
2566 HTTP_STATUS_BAD_REQUEST = 400,
2567 HTTP_STATUS_UNAUTHORIZED,
2568 HTTP_STATUS_PAYMENT_REQUIRED,
2569 HTTP_STATUS_FORBIDDEN,
2570 HTTP_STATUS_NOT_FOUND,
2571 HTTP_STATUS_METHOD_NOT_ALLOWED,
2572 HTTP_STATUS_NOT_ACCEPTABLE,
2573 HTTP_STATUS_PROXY_AUTH_REQUIRED,
2574 HTTP_STATUS_REQUEST_TIMEOUT,
2575 HTTP_STATUS_CONFLICT,
2577 HTTP_STATUS_LENGTH_REQUIRED,
2578 HTTP_STATUS_PRECONDITION_FAILED,
2579 HTTP_STATUS_REQ_ENTITY_TOO_LARGE,
2580 HTTP_STATUS_REQ_URI_TOO_LONG,
2581 HTTP_STATUS_UNSUPPORTED_MEDIA_TYPE,
2582 HTTP_STATUS_REQ_RANGE_NOT_SATISFIABLE,
2583 HTTP_STATUS_EXPECTATION_FAILED,
2585 HTTP_STATUS_INTERNAL_SERVER_ERROR = 500,
2586 HTTP_STATUS_NOT_IMPLEMENTED,
2587 HTTP_STATUS_BAD_GATEWAY,
2588 HTTP_STATUS_SERVICE_UNAVAILABLE,
2589 HTTP_STATUS_GATEWAY_TIMEOUT,
2590 HTTP_STATUS_HTTP_VERSION_NOT_SUPPORTED,
2593 struct lws_process_html_args {
2594 char *p; /**< pointer to the buffer containing the data */
2595 int len; /**< length of the original data at p */
2596 int max_len; /**< maximum length we can grow the data to */
2597 int final; /**< set if this is the last chunk of the file */
2600 typedef const char *(*lws_process_html_state_cb)(void *data, int index);
2602 struct lws_process_html_state {
2603 char *start; /**< pointer to start of match */
2604 char swallow[16]; /**< matched character buffer */
2605 int pos; /**< position in match */
2606 void *data; /**< opaque pointer */
2607 const char * const *vars; /**< list of variable names */
2608 int count_vars; /**< count of variable names */
2610 lws_process_html_state_cb replace; /**< called on match to perform substitution */
2613 /*! lws_chunked_html_process() - generic chunked substitution
2614 * \param args: buffer to process using chunked encoding
2615 * \param s: current processing state
2617 LWS_VISIBLE LWS_EXTERN int
2618 lws_chunked_html_process(struct lws_process_html_args *args,
2619 struct lws_process_html_state *s);
2622 /** \defgroup HTTP-headers-read HTTP headers: read
2625 * ##HTTP header releated functions
2627 * In lws the client http headers are temporarily stored in a pool, only for the
2628 * duration of the http part of the handshake. It's because in most cases,
2629 * the header content is ignored for the whole rest of the connection lifetime
2630 * and would then just be taking up space needlessly.
2632 * During LWS_CALLBACK_HTTP when the URI path is delivered is the last time
2633 * the http headers are still allocated, you can use these apis then to
2634 * look at and copy out interesting header content (cookies, etc)
2636 * Notice that the header total length reported does not include a terminating
2637 * '\0', however you must allocate for it when using the _copy apis. So the
2638 * length reported for a header containing "123" is 3, but you must provide
2639 * a buffer of length 4 so that "123\0" may be copied into it, or the copy
2640 * will fail with a nonzero return code.
2642 * In the special case of URL arguments, like ?x=1&y=2, the arguments are
2643 * stored in a token named for the method, eg, WSI_TOKEN_GET_URI if it
2644 * was a GET or WSI_TOKEN_POST_URI if POST. You can check the total
2645 * length to confirm the method.
2647 * For URL arguments, each argument is stored urldecoded in a "fragment", so
2648 * you can use the fragment-aware api lws_hdr_copy_fragment() to access each
2649 * argument in turn: the fragments contain urldecoded strings like x=1 or y=2.
2651 * As a convenience, lws has an api that will find the fragment with a
2652 * given name= part, lws_get_urlarg_by_name().
2656 /** struct lws_tokens
2657 * you need these to look at headers that have been parsed if using the
2658 * LWS_CALLBACK_FILTER_CONNECTION callback. If a header from the enum
2659 * list below is absent, .token = NULL and token_len = 0. Otherwise .token
2660 * points to .token_len chars containing that header content.
2663 char *token; /**< pointer to start of the token */
2664 int token_len; /**< length of the token's value */
2667 /* enum lws_token_indexes
2668 * these have to be kept in sync with lextable.h / minilex.c
2670 * NOTE: These public enums are part of the abi. If you want to add one,
2671 * add it at where specified so existing users are unaffected.
2673 enum lws_token_indexes {
2674 WSI_TOKEN_GET_URI = 0,
2675 WSI_TOKEN_POST_URI = 1,
2676 WSI_TOKEN_OPTIONS_URI = 2,
2678 WSI_TOKEN_CONNECTION = 4,
2679 WSI_TOKEN_UPGRADE = 5,
2680 WSI_TOKEN_ORIGIN = 6,
2681 WSI_TOKEN_DRAFT = 7,
2682 WSI_TOKEN_CHALLENGE = 8,
2683 WSI_TOKEN_EXTENSIONS = 9,
2684 WSI_TOKEN_KEY1 = 10,
2685 WSI_TOKEN_KEY2 = 11,
2686 WSI_TOKEN_PROTOCOL = 12,
2687 WSI_TOKEN_ACCEPT = 13,
2688 WSI_TOKEN_NONCE = 14,
2689 WSI_TOKEN_HTTP = 15,
2690 WSI_TOKEN_HTTP2_SETTINGS = 16,
2691 WSI_TOKEN_HTTP_ACCEPT = 17,
2692 WSI_TOKEN_HTTP_AC_REQUEST_HEADERS = 18,
2693 WSI_TOKEN_HTTP_IF_MODIFIED_SINCE = 19,
2694 WSI_TOKEN_HTTP_IF_NONE_MATCH = 20,
2695 WSI_TOKEN_HTTP_ACCEPT_ENCODING = 21,
2696 WSI_TOKEN_HTTP_ACCEPT_LANGUAGE = 22,
2697 WSI_TOKEN_HTTP_PRAGMA = 23,
2698 WSI_TOKEN_HTTP_CACHE_CONTROL = 24,
2699 WSI_TOKEN_HTTP_AUTHORIZATION = 25,
2700 WSI_TOKEN_HTTP_COOKIE = 26,
2701 WSI_TOKEN_HTTP_CONTENT_LENGTH = 27,
2702 WSI_TOKEN_HTTP_CONTENT_TYPE = 28,
2703 WSI_TOKEN_HTTP_DATE = 29,
2704 WSI_TOKEN_HTTP_RANGE = 30,
2705 WSI_TOKEN_HTTP_REFERER = 31,
2707 WSI_TOKEN_VERSION = 33,
2708 WSI_TOKEN_SWORIGIN = 34,
2710 WSI_TOKEN_HTTP_COLON_AUTHORITY = 35,
2711 WSI_TOKEN_HTTP_COLON_METHOD = 36,
2712 WSI_TOKEN_HTTP_COLON_PATH = 37,
2713 WSI_TOKEN_HTTP_COLON_SCHEME = 38,
2714 WSI_TOKEN_HTTP_COLON_STATUS = 39,
2716 WSI_TOKEN_HTTP_ACCEPT_CHARSET = 40,
2717 WSI_TOKEN_HTTP_ACCEPT_RANGES = 41,
2718 WSI_TOKEN_HTTP_ACCESS_CONTROL_ALLOW_ORIGIN = 42,
2719 WSI_TOKEN_HTTP_AGE = 43,
2720 WSI_TOKEN_HTTP_ALLOW = 44,
2721 WSI_TOKEN_HTTP_CONTENT_DISPOSITION = 45,
2722 WSI_TOKEN_HTTP_CONTENT_ENCODING = 46,
2723 WSI_TOKEN_HTTP_CONTENT_LANGUAGE = 47,
2724 WSI_TOKEN_HTTP_CONTENT_LOCATION = 48,
2725 WSI_TOKEN_HTTP_CONTENT_RANGE = 49,
2726 WSI_TOKEN_HTTP_ETAG = 50,
2727 WSI_TOKEN_HTTP_EXPECT = 51,
2728 WSI_TOKEN_HTTP_EXPIRES = 52,
2729 WSI_TOKEN_HTTP_FROM = 53,
2730 WSI_TOKEN_HTTP_IF_MATCH = 54,
2731 WSI_TOKEN_HTTP_IF_RANGE = 55,
2732 WSI_TOKEN_HTTP_IF_UNMODIFIED_SINCE = 56,
2733 WSI_TOKEN_HTTP_LAST_MODIFIED = 57,
2734 WSI_TOKEN_HTTP_LINK = 58,
2735 WSI_TOKEN_HTTP_LOCATION = 59,
2736 WSI_TOKEN_HTTP_MAX_FORWARDS = 60,
2737 WSI_TOKEN_HTTP_PROXY_AUTHENTICATE = 61,
2738 WSI_TOKEN_HTTP_PROXY_AUTHORIZATION = 62,
2739 WSI_TOKEN_HTTP_REFRESH = 63,
2740 WSI_TOKEN_HTTP_RETRY_AFTER = 64,
2741 WSI_TOKEN_HTTP_SERVER = 65,
2742 WSI_TOKEN_HTTP_SET_COOKIE = 66,
2743 WSI_TOKEN_HTTP_STRICT_TRANSPORT_SECURITY = 67,
2744 WSI_TOKEN_HTTP_TRANSFER_ENCODING = 68,
2745 WSI_TOKEN_HTTP_USER_AGENT = 69,
2746 WSI_TOKEN_HTTP_VARY = 70,
2747 WSI_TOKEN_HTTP_VIA = 71,
2748 WSI_TOKEN_HTTP_WWW_AUTHENTICATE = 72,
2750 WSI_TOKEN_PATCH_URI = 73,
2751 WSI_TOKEN_PUT_URI = 74,
2752 WSI_TOKEN_DELETE_URI = 75,
2754 WSI_TOKEN_HTTP_URI_ARGS = 76,
2755 WSI_TOKEN_PROXY = 77,
2756 WSI_TOKEN_HTTP_X_REAL_IP = 78,
2757 WSI_TOKEN_HTTP1_0 = 79,
2758 WSI_TOKEN_X_FORWARDED_FOR = 80,
2759 WSI_TOKEN_CONNECT = 81,
2760 /****** add new things just above ---^ ******/
2762 /* use token storage to stash these internally, not for
2765 _WSI_TOKEN_CLIENT_SENT_PROTOCOLS,
2766 _WSI_TOKEN_CLIENT_PEER_ADDRESS,
2767 _WSI_TOKEN_CLIENT_URI,
2768 _WSI_TOKEN_CLIENT_HOST,
2769 _WSI_TOKEN_CLIENT_ORIGIN,
2770 _WSI_TOKEN_CLIENT_METHOD,
2772 /* always last real token index*/
2775 /* parser state additions, no storage associated */
2776 WSI_TOKEN_NAME_PART,
2778 WSI_TOKEN_SKIPPING_SAW_CR,
2779 WSI_PARSING_COMPLETE,
2780 WSI_INIT_TOKEN_MUXURL,
2783 struct lws_token_limits {
2784 unsigned short token_limit[WSI_TOKEN_COUNT]; /**< max chars for this token */
2788 * lws_token_to_string() - returns a textual representation of a hdr token index
2790 * \param: token index
2792 LWS_VISIBLE LWS_EXTERN const unsigned char *
2793 lws_token_to_string(enum lws_token_indexes token);
2797 * lws_hdr_total_length: report length of all fragments of a header totalled up
2798 * The returned length does not include the space for a
2801 * \param wsi: websocket connection
2802 * \param h: which header index we are interested in
2804 LWS_VISIBLE LWS_EXTERN int LWS_WARN_UNUSED_RESULT
2805 lws_hdr_total_length(struct lws *wsi, enum lws_token_indexes h);
2808 * lws_hdr_fragment_length: report length of a single fragment of a header
2809 * The returned length does not include the space for a
2812 * \param wsi: websocket connection
2813 * \param h: which header index we are interested in
2814 * \param frag_idx: which fragment of h we want to get the length of
2816 LWS_VISIBLE LWS_EXTERN int LWS_WARN_UNUSED_RESULT
2817 lws_hdr_fragment_length(struct lws *wsi, enum lws_token_indexes h, int frag_idx);
2820 * lws_hdr_copy() - copy a single fragment of the given header to a buffer
2821 * The buffer length len must include space for an additional
2822 * terminating '\0', or it will fail returning -1.
2824 * \param wsi: websocket connection
2825 * \param dest: destination buffer
2826 * \param len: length of destination buffer
2827 * \param h: which header index we are interested in
2829 * copies the whole, aggregated header, even if it was delivered in
2830 * several actual headers piece by piece
2832 LWS_VISIBLE LWS_EXTERN int
2833 lws_hdr_copy(struct lws *wsi, char *dest, int len, enum lws_token_indexes h);
2836 * lws_hdr_copy_fragment() - copy a single fragment of the given header to a buffer
2837 * The buffer length len must include space for an additional
2838 * terminating '\0', or it will fail returning -1.
2839 * If the requested fragment index is not present, it fails
2842 * \param wsi: websocket connection
2843 * \param dest: destination buffer
2844 * \param len: length of destination buffer
2845 * \param h: which header index we are interested in
2846 * \param frag_idx: which fragment of h we want to copy
2848 * Normally this is only useful
2849 * to parse URI arguments like ?x=1&y=2, token index WSI_TOKEN_HTTP_URI_ARGS
2850 * fragment 0 will contain "x=1" and fragment 1 "y=2"
2852 LWS_VISIBLE LWS_EXTERN int
2853 lws_hdr_copy_fragment(struct lws *wsi, char *dest, int len,
2854 enum lws_token_indexes h, int frag_idx);
2857 * lws_get_urlarg_by_name() - return pointer to arg value if present
2858 * \param wsi: the connection to check
2859 * \param name: the arg name, like "token="
2860 * \param buf: the buffer to receive the urlarg (including the name= part)
2861 * \param len: the length of the buffer to receive the urlarg
2863 * Returns NULL if not found or a pointer inside buf to just after the
2866 LWS_VISIBLE LWS_EXTERN const char *
2867 lws_get_urlarg_by_name(struct lws *wsi, const char *name, char *buf, int len);
2870 /*! \defgroup HTTP-headers-create HTTP headers: create
2872 * ## HTTP headers: Create
2874 * These apis allow you to create HTTP response headers in a way compatible with
2875 * both HTTP/1.x and HTTP/2.
2877 * They each append to a buffer taking care about the buffer end, which is
2878 * passed in as a pointer. When data is written to the buffer, the current
2879 * position p is updated accordingly.
2881 * All of these apis are LWS_WARN_UNUSED_RESULT as they can run out of space
2882 * and fail with nonzero return.
2886 * lws_add_http_header_status() - add the HTTP response status code
2888 * \param wsi: the connection to check
2889 * \param code: an HTTP code like 200, 404 etc (see enum http_status)
2890 * \param p: pointer to current position in buffer pointer
2891 * \param end: pointer to end of buffer
2893 * Adds the initial response code, so should be called first
2895 LWS_VISIBLE LWS_EXTERN int LWS_WARN_UNUSED_RESULT
2896 lws_add_http_header_status(struct lws *wsi,
2897 unsigned int code, unsigned char **p,
2898 unsigned char *end);
2900 * lws_add_http_header_by_name() - append named header and value
2902 * \param wsi: the connection to check
2903 * \param name: the hdr name, like "my-header"
2904 * \param value: the value after the = for this header
2905 * \param length: the length of the value
2906 * \param p: pointer to current position in buffer pointer
2907 * \param end: pointer to end of buffer
2909 * Appends name: value to the headers
2911 LWS_VISIBLE LWS_EXTERN int LWS_WARN_UNUSED_RESULT
2912 lws_add_http_header_by_name(struct lws *wsi, const unsigned char *name,
2913 const unsigned char *value, int length,
2914 unsigned char **p, unsigned char *end);
2916 * lws_add_http_header_by_token() - append given header and value
2918 * \param wsi: the connection to check
2919 * \param token: the token index for the hdr
2920 * \param value: the value after the = for this header
2921 * \param length: the length of the value
2922 * \param p: pointer to current position in buffer pointer
2923 * \param end: pointer to end of buffer
2925 * Appends name=value to the headers, but is able to take advantage of better
2926 * HTTP/2 coding mechanisms where possible.
2928 LWS_VISIBLE LWS_EXTERN int LWS_WARN_UNUSED_RESULT
2929 lws_add_http_header_by_token(struct lws *wsi, enum lws_token_indexes token,
2930 const unsigned char *value, int length,
2931 unsigned char **p, unsigned char *end);
2933 * lws_add_http_header_by_name() - append content-length helper
2935 * \param wsi: the connection to check
2936 * \param content_length: the content length to use
2937 * \param p: pointer to current position in buffer pointer
2938 * \param end: pointer to end of buffer
2940 * Appends content-length: content_length to the headers
2942 LWS_VISIBLE LWS_EXTERN int LWS_WARN_UNUSED_RESULT
2943 lws_add_http_header_content_length(struct lws *wsi,
2944 unsigned long content_length,
2945 unsigned char **p, unsigned char *end);
2947 * lws_finalize_http_header() - terminate header block
2949 * \param wsi: the connection to check
2950 * \param p: pointer to current position in buffer pointer
2951 * \param end: pointer to end of buffer
2953 * Indicates no more headers will be added
2955 LWS_VISIBLE LWS_EXTERN int LWS_WARN_UNUSED_RESULT
2956 lws_finalize_http_header(struct lws *wsi, unsigned char **p,
2957 unsigned char *end);
2960 /** \defgroup form-parsing Form Parsing
2962 * ##POSTed form parsing functions
2964 * These lws_spa (stateful post arguments) apis let you parse and urldecode
2965 * POSTed form arguments, both using simple urlencoded and multipart transfer
2968 * It's capable of handling file uploads as well a named input parsing,
2969 * and the apis are the same for both form upload styles.
2971 * You feed it a list of parameter names and it creates pointers to the
2972 * urldecoded arguments: file upload parameters pass the file data in chunks to
2973 * a user-supplied callback as they come.
2975 * Since it's stateful, it handles the incoming data needing more than one
2976 * POST_BODY callback and has no limit on uploaded file size.
2980 /** enum lws_spa_fileupload_states */
2981 enum lws_spa_fileupload_states {
2983 /**< a chunk of file content has arrived */
2984 LWS_UFS_FINAL_CONTENT,
2985 /**< the last chunk (possibly zero length) of file content has arrived */
2987 /**< a new file is starting to arrive */
2991 * lws_spa_fileupload_cb() - callback to receive file upload data
2993 * \param data: opt_data pointer set in lws_spa_create
2994 * \param name: name of the form field being uploaded
2995 * \param filename: original filename from client
2996 * \param buf: start of data to receive
2997 * \param len: length of data to receive
2998 * \param state: information about how this call relates to file
3000 * Notice name and filename shouldn't be trusted, as they are passed from
3001 * HTTP provided by the client.
3003 typedef int (*lws_spa_fileupload_cb)(void *data, const char *name,
3004 const char *filename, char *buf, int len,
3005 enum lws_spa_fileupload_states state);
3007 /** struct lws_spa - opaque urldecode parser capable of handling multipart
3008 * and file uploads */
3012 * lws_spa_create() - create urldecode parser
3014 * \param wsi: lws connection (used to find Content Type)
3015 * \param param_names: array of form parameter names, like "username"
3016 * \param count_params: count of param_names
3017 * \param max_storage: total amount of form parameter values we can store
3018 * \param opt_cb: NULL, or callback to receive file upload data.
3019 * \param opt_data: NULL, or user pointer provided to opt_cb.
3021 * Creates a urldecode parser and initializes it.
3023 * opt_cb can be NULL if you just want normal name=value parsing, however
3024 * if one or more entries in your form are bulk data (file transfer), you
3025 * can provide this callback and filter on the name callback parameter to
3026 * treat that urldecoded data separately. The callback should return -1
3027 * in case of fatal error, and 0 if OK.
3029 LWS_VISIBLE LWS_EXTERN struct lws_spa *
3030 lws_spa_create(struct lws *wsi, const char * const *param_names,
3031 int count_params, int max_storage, lws_spa_fileupload_cb opt_cb,
3035 * lws_spa_process() - parses a chunk of input data
3037 * \param spa: the parser object previously created
3038 * \param in: incoming, urlencoded data
3039 * \param len: count of bytes valid at \param in
3041 LWS_VISIBLE LWS_EXTERN int
3042 lws_spa_process(struct lws_spa *spa, const char *in, int len);
3045 * lws_spa_finalize() - indicate incoming data completed
3047 * \param spa: the parser object previously created
3049 LWS_VISIBLE LWS_EXTERN int
3050 lws_spa_finalize(struct lws_spa *spa);
3053 * lws_spa_get_length() - return length of parameter value
3055 * \param spa: the parser object previously created
3056 * \param n: parameter ordinal to return length of value for
3058 LWS_VISIBLE LWS_EXTERN int
3059 lws_spa_get_length(struct lws_spa *spa, int n);
3062 * lws_spa_get_string() - return pointer to parameter value
3063 * \param spa: the parser object previously created
3064 * \param n: parameter ordinal to return pointer to value for
3066 LWS_VISIBLE LWS_EXTERN const char *
3067 lws_spa_get_string(struct lws_spa *spa, int n);
3070 * lws_spa_destroy() - destroy parser object
3072 * \param spa: the parser object previously created
3074 LWS_VISIBLE LWS_EXTERN int
3075 lws_spa_destroy(struct lws_spa *spa);
3078 /*! \defgroup urlendec Urlencode and Urldecode
3081 * ##HTML chunked Substitution
3083 * APIs for receiving chunks of text, replacing a set of variable names via
3084 * a callback, and then prepending and appending HTML chunked encoding
3090 * lws_urlencode() - like strncpy but with urlencoding
3092 * \param escaped: output buffer
3093 * \param string: input buffer ('/0' terminated)
3094 * \param len: output buffer max length
3096 * Because urlencoding expands the output string, it's not
3097 * possible to do it in-place, ie, with escaped == string
3099 LWS_VISIBLE LWS_EXTERN const char *
3100 lws_urlencode(char *escaped, const char *string, int len);
3105 * This simple urldecode only operates until the first '\0' and requires the
3106 * data to exist all at once
3109 * lws_urldecode() - like strncpy but with urldecoding
3111 * \param string: output buffer
3112 * \param escaped: input buffer ('\0' terminated)
3113 * \param len: output buffer max length
3115 * This is only useful for '\0' terminated strings
3117 * Since urldecoding only shrinks the output string, it is possible to
3118 * do it in-place, ie, string == escaped
3120 LWS_VISIBLE LWS_EXTERN int
3121 lws_urldecode(char *string, const char *escaped, int len);
3124 * lws_return_http_status() - Return simple http status
3125 * \param wsi: Websocket instance (available from user callback)
3126 * \param code: Status index, eg, 404
3127 * \param html_body: User-readable HTML description < 1KB, or NULL
3129 * Helper to report HTTP errors back to the client cleanly and
3132 LWS_VISIBLE LWS_EXTERN int
3133 lws_return_http_status(struct lws *wsi, unsigned int code,
3134 const char *html_body);
3137 * lws_http_redirect() - write http redirect into buffer
3139 * \param wsi: websocket connection
3140 * \param code: HTTP response code (eg, 301)
3141 * \param loc: where to redirect to
3142 * \param len: length of loc
3143 * \param p: pointer current position in buffer (updated as we write)
3144 * \param end: pointer to end of buffer
3146 LWS_VISIBLE LWS_EXTERN int LWS_WARN_UNUSED_RESULT
3147 lws_http_redirect(struct lws *wsi, int code, const unsigned char *loc, int len,
3148 unsigned char **p, unsigned char *end);
3151 * lws_http_transaction_completed() - wait for new http transaction or close
3152 * \param wsi: websocket connection
3154 * Returns 1 if the HTTP connection must close now
3155 * Returns 0 and resets connection to wait for new HTTP header /
3156 * transaction if possible
3158 LWS_VISIBLE LWS_EXTERN int LWS_WARN_UNUSED_RESULT
3159 lws_http_transaction_completed(struct lws *wsi);
3162 /*! \defgroup pur Sanitize / purify SQL and JSON helpers
3164 * ##Sanitize / purify SQL and JSON helpers
3166 * APIs for escaping untrusted JSON and SQL safely before use
3171 * lws_sql_purify() - like strncpy but with escaping for sql quotes
3173 * \param escaped: output buffer
3174 * \param string: input buffer ('/0' terminated)
3175 * \param len: output buffer max length
3177 * Because escaping expands the output string, it's not
3178 * possible to do it in-place, ie, with escaped == string
3180 LWS_VISIBLE LWS_EXTERN const char *
3181 lws_sql_purify(char *escaped, const char *string, int len);
3184 * lws_json_purify() - like strncpy but with escaping for json chars
3186 * \param escaped: output buffer
3187 * \param string: input buffer ('/0' terminated)
3188 * \param len: output buffer max length
3190 * Because escaping expands the output string, it's not
3191 * possible to do it in-place, ie, with escaped == string
3193 LWS_VISIBLE LWS_EXTERN const char *
3194 lws_json_purify(char *escaped, const char *string, int len);
3197 /*! \defgroup ev libev helpers
3201 * APIs specific to libev event loop itegration
3205 #ifdef LWS_USE_LIBEV
3206 typedef void (lws_ev_signal_cb_t)(EV_P_ struct ev_signal *w, int revents);
3208 LWS_VISIBLE LWS_EXTERN int
3209 lws_ev_sigint_cfg(struct lws_context *context, int use_ev_sigint,
3210 lws_ev_signal_cb_t *cb);
3212 LWS_VISIBLE LWS_EXTERN int
3213 lws_ev_initloop(struct lws_context *context, struct ev_loop *loop, int tsi);
3215 LWS_VISIBLE LWS_EXTERN void
3216 lws_ev_sigint_cb(struct ev_loop *loop, struct ev_signal *watcher, int revents);
3217 #endif /* LWS_USE_LIBEV */
3221 /*! \defgroup uv libuv helpers
3225 * APIs specific to libuv event loop itegration
3228 #ifdef LWS_USE_LIBUV
3229 LWS_VISIBLE LWS_EXTERN int
3230 lws_uv_sigint_cfg(struct lws_context *context, int use_uv_sigint,
3233 LWS_VISIBLE LWS_EXTERN void
3234 lws_libuv_run(const struct lws_context *context, int tsi);
3236 LWS_VISIBLE LWS_EXTERN void
3237 lws_libuv_stop(struct lws_context *context);
3239 LWS_VISIBLE LWS_EXTERN void
3240 lws_libuv_stop_without_kill(const struct lws_context *context, int tsi);
3242 LWS_VISIBLE LWS_EXTERN int
3243 lws_uv_initloop(struct lws_context *context, uv_loop_t *loop, int tsi);
3245 LWS_VISIBLE LWS_EXTERN uv_loop_t *
3246 lws_uv_getloop(struct lws_context *context, int tsi);
3248 LWS_VISIBLE LWS_EXTERN void
3249 lws_uv_sigint_cb(uv_signal_t *watcher, int signum);
3250 #endif /* LWS_USE_LIBUV */
3253 /*! \defgroup timeout Connection timeouts
3255 APIs related to setting connection timeouts
3260 * NOTE: These public enums are part of the abi. If you want to add one,
3261 * add it at where specified so existing users are unaffected.
3263 enum pending_timeout {
3264 NO_PENDING_TIMEOUT = 0,
3265 PENDING_TIMEOUT_AWAITING_PROXY_RESPONSE = 1,
3266 PENDING_TIMEOUT_AWAITING_CONNECT_RESPONSE = 2,
3267 PENDING_TIMEOUT_ESTABLISH_WITH_SERVER = 3,
3268 PENDING_TIMEOUT_AWAITING_SERVER_RESPONSE = 4,
3269 PENDING_TIMEOUT_AWAITING_PING = 5,
3270 PENDING_TIMEOUT_CLOSE_ACK = 6,
3271 PENDING_TIMEOUT_AWAITING_EXTENSION_CONNECT_RESPONSE = 7,
3272 PENDING_TIMEOUT_SENT_CLIENT_HANDSHAKE = 8,
3273 PENDING_TIMEOUT_SSL_ACCEPT = 9,
3274 PENDING_TIMEOUT_HTTP_CONTENT = 10,
3275 PENDING_TIMEOUT_AWAITING_CLIENT_HS_SEND = 11,
3276 PENDING_FLUSH_STORED_SEND_BEFORE_CLOSE = 12,
3277 PENDING_TIMEOUT_SHUTDOWN_FLUSH = 13,
3278 PENDING_TIMEOUT_CGI = 14,
3279 PENDING_TIMEOUT_HTTP_KEEPALIVE_IDLE = 15,
3280 PENDING_TIMEOUT_WS_PONG_CHECK_SEND_PING = 16,
3281 PENDING_TIMEOUT_WS_PONG_CHECK_GET_PONG = 17,
3282 PENDING_TIMEOUT_CLIENT_ISSUE_PAYLOAD = 18,
3284 /****** add new things just above ---^ ******/
3288 * lws_set_timeout() - marks the wsi as subject to a timeout
3290 * You will not need this unless you are doing something special
3292 * \param wsi: Websocket connection instance
3293 * \param reason: timeout reason
3294 * \param secs: how many seconds
3296 LWS_VISIBLE LWS_EXTERN void
3297 lws_set_timeout(struct lws *wsi, enum pending_timeout reason, int secs);
3300 /*! \defgroup sending-data Sending data
3302 APIs related to writing data on a connection
3305 #if !defined(LWS_SIZEOFPTR)
3306 #define LWS_SIZEOFPTR (sizeof (void *))
3308 #if !defined(u_int64_t)
3309 #define u_int64_t unsigned long long
3312 #if defined(__x86_64__)
3313 #define _LWS_PAD_SIZE 16 /* Intel recommended for best performance */
3315 #define _LWS_PAD_SIZE LWS_SIZEOFPTR /* Size of a pointer on the target arch */
3317 #define _LWS_PAD(n) (((n) % _LWS_PAD_SIZE) ? \
3318 ((n) + (_LWS_PAD_SIZE - ((n) % _LWS_PAD_SIZE))) : (n))
3319 #define LWS_PRE _LWS_PAD(4 + 10)
3320 /* used prior to 1.7 and retained for backward compatibility */
3321 #define LWS_SEND_BUFFER_PRE_PADDING LWS_PRE
3322 #define LWS_SEND_BUFFER_POST_PADDING 0
3325 * NOTE: These public enums are part of the abi. If you want to add one,
3326 * add it at where specified so existing users are unaffected.
3328 enum lws_write_protocol {
3330 /**< Send a ws TEXT message,the pointer must have LWS_PRE valid
3331 * memory behind it. The receiver expects only valid utf-8 in the
3333 LWS_WRITE_BINARY = 1,
3334 /**< Send a ws BINARY message, the pointer must have LWS_PRE valid
3335 * memory behind it. Any sequence of bytes is valid */
3336 LWS_WRITE_CONTINUATION = 2,
3337 /**< Continue a previous ws message, the pointer must have LWS_PRE valid
3338 * memory behind it */
3340 /**< Send HTTP content */
3342 /* LWS_WRITE_CLOSE is handled by lws_close_reason() */
3346 /* Same as write_http but we know this write ends the transaction */
3347 LWS_WRITE_HTTP_FINAL = 7,
3351 LWS_WRITE_HTTP_HEADERS = 8,
3352 /**< Send http headers (http2 encodes this payload and LWS_WRITE_HTTP
3353 * payload differently, http 1.x links also handle this correctly. so
3354 * to be compatible with both in the future,header response part should
3355 * be sent using this regardless of http version expected)
3358 /****** add new things just above ---^ ******/
3362 LWS_WRITE_NO_FIN = 0x40,
3363 /**< This part of the message is not the end of the message */
3365 LWS_WRITE_CLIENT_IGNORE_XOR_MASK = 0x80
3366 /**< client packet payload goes out on wire unmunged
3367 * only useful for security tests since normal servers cannot
3368 * decode the content if used */
3373 * lws_write() - Apply protocol then write data to client
3374 * \param wsi: Websocket instance (available from user callback)
3375 * \param buf: The data to send. For data being sent on a websocket
3376 * connection (ie, not default http), this buffer MUST have
3377 * LWS_PRE bytes valid BEFORE the pointer.
3378 * This is so the protocol header data can be added in-situ.
3379 * \param len: Count of the data bytes in the payload starting from buf
3380 * \param protocol: Use LWS_WRITE_HTTP to reply to an http connection, and one
3381 * of LWS_WRITE_BINARY or LWS_WRITE_TEXT to send appropriate
3382 * data on a websockets connection. Remember to allow the extra
3383 * bytes before and after buf if LWS_WRITE_BINARY or LWS_WRITE_TEXT
3386 * This function provides the way to issue data back to the client
3387 * for both http and websocket protocols.
3391 * When sending with websocket protocol
3395 * LWS_WRITE_CONTINUATION,
3399 * the send buffer has to have LWS_PRE bytes valid BEFORE
3400 * the buffer pointer you pass to lws_write().
3402 * This allows us to add protocol info before and after the data, and send as
3403 * one packet on the network without payload copying, for maximum efficiency.
3405 * So for example you need this kind of code to use lws_write with a
3408 * char buf[LWS_PRE + 128];
3410 * // fill your part of the buffer... for example here it's all zeros
3411 * memset(&buf[LWS_PRE], 0, 128);
3413 * lws_write(wsi, &buf[LWS_PRE], 128, LWS_WRITE_TEXT);
3415 * When sending HTTP, with
3418 * LWS_WRITE_HTTP_HEADERS
3419 * LWS_WRITE_HTTP_FINAL
3421 * there is no protocol data prepended, and don't need to take care about the
3422 * LWS_PRE bytes valid before the buffer pointer.
3424 * LWS_PRE is at least the frame nonce + 2 header + 8 length
3425 * LWS_SEND_BUFFER_POST_PADDING is deprecated, it's now 0 and can be left off.
3426 * The example apps no longer use it.
3428 * Pad LWS_PRE to the CPU word size, so that word references
3429 * to the address immediately after the padding won't cause an unaligned access
3430 * error. Sometimes for performance reasons the recommended padding is even
3431 * larger than sizeof(void *).
3433 * In the case of sending using websocket protocol, be sure to allocate
3434 * valid storage before and after buf as explained above. This scheme
3435 * allows maximum efficiency of sending data and protocol in a single
3436 * packet while not burdening the user code with any protocol knowledge.
3438 * Return may be -1 for a fatal error needing connection close, or the
3439 * number of bytes sent.
3444 * The OS may not accept everything you asked to write on the connection.
3446 * Posix defines POLLOUT indication from poll() to show that the connection
3447 * will accept more write data, but it doesn't specifiy how much. It may just
3448 * accept one byte of whatever you wanted to send.
3450 * LWS will buffer the remainder automatically, and send it out autonomously.
3452 * During that time, WRITABLE callbacks will be suppressed.
3454 * This is to handle corner cases where unexpectedly the OS refuses what we
3455 * usually expect it to accept. You should try to send in chunks that are
3456 * almost always accepted in order to avoid the inefficiency of the buffering.
3458 LWS_VISIBLE LWS_EXTERN int
3459 lws_write(struct lws *wsi, unsigned char *buf, size_t len,
3460 enum lws_write_protocol protocol);
3462 /* helper for case where buffer may be const */
3463 #define lws_write_http(wsi, buf, len) \
3464 lws_write(wsi, (unsigned char *)(buf), len, LWS_WRITE_HTTP)
3467 /** \defgroup callback-when-writeable Callback when writeable
3469 * ##Callback When Writeable
3471 * lws can only write data on a connection when it is able to accept more
3472 * data without blocking.
3474 * So a basic requirement is we should only use the lws_write() apis when the
3475 * connection we want to write on says that he can accept more data.
3477 * When lws cannot complete your send at the time, it will buffer the data
3478 * and send it in the background, suppressing any further WRITEABLE callbacks
3479 * on that connection until it completes. So it is important to write new
3480 * things in a new writeable callback.
3482 * These apis reflect the various ways we can indicate we would like to be
3483 * called back when one or more connections is writeable.
3488 * lws_callback_on_writable() - Request a callback when this socket
3489 * becomes able to be written to without
3492 * \param wsi: Websocket connection instance to get callback for
3494 * - Which: only this wsi
3495 * - When: when the individual connection becomes writeable
3496 * - What: LWS_CALLBACK_*_WRITEABLE
3498 LWS_VISIBLE LWS_EXTERN int
3499 lws_callback_on_writable(struct lws *wsi);
3502 * lws_callback_on_writable_all_protocol() - Request a callback for all
3503 * connections on same vhost using the given protocol when it
3504 * becomes possible to write to each socket without
3507 * \param context: lws_context
3508 * \param protocol: Protocol whose connections will get callbacks
3510 * - Which: connections using this protocol on ANY VHOST
3511 * - When: when the individual connection becomes writeable
3512 * - What: LWS_CALLBACK_*_WRITEABLE
3514 LWS_VISIBLE LWS_EXTERN int
3515 lws_callback_on_writable_all_protocol(const struct lws_context *context,
3516 const struct lws_protocols *protocol);
3519 * lws_callback_on_writable_all_protocol_vhost() - Request a callback for
3520 * all connections using the given protocol when it
3521 * becomes possible to write to each socket without
3524 * \param vhost: Only consider connections on this lws_vhost
3525 * \param protocol: Protocol whose connections will get callbacks
3527 * - Which: connections using this protocol on GIVEN VHOST ONLY
3528 * - When: when the individual connection becomes writeable
3529 * - What: LWS_CALLBACK_*_WRITEABLE
3531 LWS_VISIBLE LWS_EXTERN int
3532 lws_callback_on_writable_all_protocol_vhost(const struct lws_vhost *vhost,
3533 const struct lws_protocols *protocol);
3536 * lws_callback_all_protocol() - Callback all connections using
3537 * the given protocol with the given reason
3539 * \param context: lws_context
3540 * \param protocol: Protocol whose connections will get callbacks
3541 * \param reason: Callback reason index
3543 * - Which: connections using this protocol on ALL VHOSTS
3544 * - When: when the individual connection becomes writeable
3547 LWS_VISIBLE LWS_EXTERN int
3548 lws_callback_all_protocol(struct lws_context *context,
3549 const struct lws_protocols *protocol, int reason);
3552 * lws_callback_all_protocol_vhost() - Callback all connections using
3553 * the given protocol with the given reason
3555 * \param vh: Vhost whose connections will get callbacks
3556 * \param protocol: Which protocol to match
3557 * \param reason: Callback reason index
3559 * - Which: connections using this protocol on GIVEN VHOST ONLY
3563 LWS_VISIBLE LWS_EXTERN int
3564 lws_callback_all_protocol_vhost(struct lws_vhost *vh,
3565 const struct lws_protocols *protocol, int reason);
3568 * lws_callback_vhost_protocols() - Callback all protocols enabled on a vhost
3569 * with the given reason
3571 * \param wsi: wsi whose vhost will get callbacks
3572 * \param reason: Callback reason index
3573 * \param in: in argument to callback
3574 * \param len: len argument to callback
3576 * - Which: connections using this protocol on same VHOST as wsi ONLY
3580 LWS_VISIBLE LWS_EXTERN int
3581 lws_callback_vhost_protocols(struct lws *wsi, int reason, void *in, int len);
3583 LWS_VISIBLE LWS_EXTERN int
3584 lws_callback_http_dummy(struct lws *wsi, enum lws_callback_reasons reason,
3585 void *user, void *in, size_t len);
3588 * lws_get_socket_fd() - returns the socket file descriptor
3590 * You will not need this unless you are doing something special
3592 * \param wsi: Websocket connection instance
3594 LWS_VISIBLE LWS_EXTERN int
3595 lws_get_socket_fd(struct lws *wsi);
3598 * lws_get_peer_write_allowance() - get the amount of data writeable to peer
3601 * \param wsi: Websocket connection instance
3603 * if the protocol does not have any guidance, returns -1. Currently only
3604 * http2 connections get send window information from this API. But your code
3605 * should use it so it can work properly with any protocol.
3607 * If nonzero return is the amount of payload data the peer or intermediary has
3608 * reported it has buffer space for. That has NO relationship with the amount
3609 * of buffer space your OS can accept on this connection for a write action.
3611 * This number represents the maximum you could send to the peer or intermediary
3612 * on this connection right now without the protocol complaining.
3614 * lws manages accounting for send window updates and payload writes
3615 * automatically, so this number reflects the situation at the peer or
3616 * intermediary dynamically.
3618 LWS_VISIBLE LWS_EXTERN size_t
3619 lws_get_peer_write_allowance(struct lws *wsi);
3623 * lws_rx_flow_control() - Enable and disable socket servicing for
3626 * If the output side of a server process becomes choked, this allows flow
3627 * control for the input side.
3629 * \param wsi: Websocket connection instance to get callback for
3630 * \param enable: 0 = disable read servicing for this connection, 1 = enable
3632 LWS_VISIBLE LWS_EXTERN int
3633 lws_rx_flow_control(struct lws *wsi, int enable);
3636 * lws_rx_flow_allow_all_protocol() - Allow all connections with this protocol to receive
3638 * When the user server code realizes it can accept more input, it can
3639 * call this to have the RX flow restriction removed from all connections using
3640 * the given protocol.
3641 * \param context: lws_context
3642 * \param protocol: all connections using this protocol will be allowed to receive
3644 LWS_VISIBLE LWS_EXTERN void
3645 lws_rx_flow_allow_all_protocol(const struct lws_context *context,
3646 const struct lws_protocols *protocol);
3649 * lws_remaining_packet_payload() - Bytes to come before "overall"
3650 * rx packet is complete
3651 * \param wsi: Websocket instance (available from user callback)
3653 * This function is intended to be called from the callback if the
3654 * user code is interested in "complete packets" from the client.
3655 * libwebsockets just passes through payload as it comes and issues a buffer
3656 * additionally when it hits a built-in limit. The LWS_CALLBACK_RECEIVE
3657 * callback handler can use this API to find out if the buffer it has just
3658 * been given is the last piece of a "complete packet" from the client --
3659 * when that is the case lws_remaining_packet_payload() will return
3662 * Many protocols won't care becuse their packets are always small.
3664 LWS_VISIBLE LWS_EXTERN size_t
3665 lws_remaining_packet_payload(struct lws *wsi);
3668 /** \defgroup sock-adopt Socket adoption helpers
3669 * ##Socket adoption helpers
3671 * When integrating with an external app with its own event loop, these can
3672 * be used to accept connections from someone else's listening socket.
3674 * When using lws own event loop, these are not needed.
3679 * lws_adopt_socket() - adopt foreign socket as if listen socket accepted it
3680 * for the default vhost of context.
3681 * \param context: lws context
3682 * \param accept_fd: fd of already-accepted socket to adopt
3684 * Either returns new wsi bound to accept_fd, or closes accept_fd and
3685 * returns NULL, having cleaned up any new wsi pieces.
3687 * LWS adopts the socket in http serving mode, it's ready to accept an upgrade
3688 * to ws or just serve http.
3690 LWS_VISIBLE LWS_EXTERN struct lws *
3691 lws_adopt_socket(struct lws_context *context, lws_sockfd_type accept_fd);
3693 * lws_adopt_socket_vhost() - adopt foreign socket as if listen socket accepted it
3695 * \param vhost: lws vhost
3696 * \param accept_fd: fd of already-accepted socket to adopt
3698 * Either returns new wsi bound to accept_fd, or closes accept_fd and
3699 * returns NULL, having cleaned up any new wsi pieces.
3701 * LWS adopts the socket in http serving mode, it's ready to accept an upgrade
3702 * to ws or just serve http.
3704 LWS_VISIBLE LWS_EXTERN struct lws *
3705 lws_adopt_socket_vhost(struct lws_vhost *vh, lws_sockfd_type accept_fd);
3707 * lws_adopt_socket_vhost2() - adopt foreign socket as if listen socket accepted it
3708 * for vhost, allow control over defeat SSL and raw transport mode
3709 * \param vhost: lws vhost
3710 * \param accept_fd: fd of already-accepted socket to adopt
3711 * \param allow_ssl: 0 = no SSL even if vhost supports, 1 = SSL if vhost supports
3712 * \param raw: 0 = http[s]/wss[s], 1 = raw mode semantics
3714 * Either returns new wsi bound to accept_fd, or closes accept_fd and
3715 * returns NULL, having cleaned up any new wsi pieces.
3717 * LWS adopts the socket in http serving mode, it's ready to accept an upgrade
3718 * to ws or just serve http.
3720 LWS_VISIBLE struct lws *
3721 lws_adopt_socket_vhost2(struct lws_vhost *vh, lws_sockfd_type accept_fd,
3722 int allow_ssl, int raw);
3725 * lws_adopt_socket_readbuf() - adopt foreign socket and first rx as if listen socket accepted it
3726 * for the default vhost of context.
3727 * \param context: lws context
3728 * \param accept_fd: fd of already-accepted socket to adopt
3729 * \param readbuf: NULL or pointer to data that must be drained before reading from
3731 * \param len: The length of the data held at \param readbuf
3733 * Either returns new wsi bound to accept_fd, or closes accept_fd and
3734 * returns NULL, having cleaned up any new wsi pieces.
3736 * LWS adopts the socket in http serving mode, it's ready to accept an upgrade
3737 * to ws or just serve http.
3739 * If your external code did not already read from the socket, you can use
3740 * lws_adopt_socket() instead.
3742 * This api is guaranteed to use the data at \param readbuf first, before reading from
3745 * readbuf is limited to the size of the ah rx buf, currently 2048 bytes.
3747 LWS_VISIBLE LWS_EXTERN struct lws *
3748 lws_adopt_socket_readbuf(struct lws_context *context, lws_sockfd_type accept_fd,
3749 const char *readbuf, size_t len);
3751 * lws_adopt_socket_vhost_readbuf() - adopt foreign socket and first rx as if listen socket
3752 * accepted it for vhost.
3753 * \param vhost: lws vhost
3754 * \param accept_fd: fd of already-accepted socket to adopt
3755 * \param readbuf: NULL or pointer to data that must be drained before reading from
3757 * \param len: The length of the data held at \param readbuf
3759 * Either returns new wsi bound to accept_fd, or closes accept_fd and
3760 * returns NULL, having cleaned up any new wsi pieces.
3762 * LWS adopts the socket in http serving mode, it's ready to accept an upgrade
3763 * to ws or just serve http.
3765 * If your external code did not already read from the socket, you can use
3766 * lws_adopt_socket() instead.
3768 * This api is guaranteed to use the data at \param readbuf first, before reading from
3771 * readbuf is limited to the size of the ah rx buf, currently 2048 bytes.
3773 LWS_VISIBLE LWS_EXTERN struct lws *
3774 lws_adopt_socket_vhost_readbuf(struct lws_vhost *vhost, lws_sockfd_type accept_fd,
3775 const char *readbuf, size_t len);
3778 /** \defgroup net Network related helper APIs
3779 * ##Network related helper APIs
3781 * These wrap miscellaneous useful network-related functions
3786 * lws_canonical_hostname() - returns this host's hostname
3788 * This is typically used by client code to fill in the host parameter
3789 * when making a client connection. You can only call it after the context
3792 * \param context: Websocket context
3794 LWS_VISIBLE LWS_EXTERN const char * LWS_WARN_UNUSED_RESULT
3795 lws_canonical_hostname(struct lws_context *context);
3798 * lws_get_peer_addresses() - Get client address information
3799 * \param wsi: Local struct lws associated with
3800 * \param fd: Connection socket descriptor
3801 * \param name: Buffer to take client address name
3802 * \param name_len: Length of client address name buffer
3803 * \param rip: Buffer to take client address IP dotted quad
3804 * \param rip_len: Length of client address IP buffer
3806 * This function fills in name and rip with the name and IP of
3807 * the client connected with socket descriptor fd. Names may be
3808 * truncated if there is not enough room. If either cannot be
3809 * determined, they will be returned as valid zero-length strings.
3811 LWS_VISIBLE LWS_EXTERN void
3812 lws_get_peer_addresses(struct lws *wsi, lws_sockfd_type fd, char *name,
3813 int name_len, char *rip, int rip_len);
3816 * lws_get_peer_simple() - Get client address information without RDNS
3818 * \param wsi: Local struct lws associated with
3819 * \param name: Buffer to take client address name
3820 * \param namelen: Length of client address name buffer
3822 * This provides a 123.123.123.123 type IP address in name from the
3823 * peer that has connected to wsi
3825 LWS_VISIBLE LWS_EXTERN const char *
3826 lws_get_peer_simple(struct lws *wsi, char *name, int namelen);
3827 #if !defined(LWS_WITH_ESP8266) && !defined(LWS_WITH_ESP32)
3829 * lws_interface_to_sa() - Convert interface name or IP to sockaddr struct
3831 * \param ipv6: Allow IPV6 addresses
3832 * \param ifname: Interface name or IP
3833 * \param addr: struct sockaddr_in * to be written
3834 * \param addrlen: Length of addr
3836 * This converts a textual network interface name to a sockaddr usable by
3837 * other network functions
3839 LWS_VISIBLE LWS_EXTERN int
3840 lws_interface_to_sa(int ipv6, const char *ifname, struct sockaddr_in *addr,
3845 /** \defgroup misc Miscellaneous APIs
3846 * ##Miscellaneous APIs
3848 * Various APIs outside of other categories
3853 * lws_snprintf(): snprintf that truncates the returned length too
3855 * \param str: destination buffer
3856 * \param size: bytes left in destination buffer
3857 * \param format: format string
3858 * \param ...: args for format
3860 * This lets you correctly truncate buffers by concatenating lengths, if you
3861 * reach the limit the reported length doesn't exceed the limit.
3863 LWS_VISIBLE LWS_EXTERN int
3864 lws_snprintf(char *str, size_t size, const char *format, ...) LWS_FORMAT(3);
3867 * lws_get_random(): fill a buffer with platform random data
3869 * \param context: the lws context
3870 * \param buf: buffer to fill
3871 * \param len: how much to fill
3873 * This is intended to be called from the LWS_CALLBACK_RECEIVE callback if
3874 * it's interested to see if the frame it's dealing with was sent in binary
3877 LWS_VISIBLE LWS_EXTERN int
3878 lws_get_random(struct lws_context *context, void *buf, int len);
3880 * lws_daemonize(): make current process run in the background
3882 * \param _lock_path: the filepath to write the lock file
3884 * Spawn lws as a background process, taking care of various things
3886 LWS_VISIBLE LWS_EXTERN int LWS_WARN_UNUSED_RESULT
3887 lws_daemonize(const char *_lock_path);
3889 * lws_get_library_version(): return string describing the version of lws
3891 * On unix, also includes the git describe
3893 LWS_VISIBLE LWS_EXTERN const char * LWS_WARN_UNUSED_RESULT
3894 lws_get_library_version(void);
3897 * lws_wsi_user() - get the user data associated with the connection
3898 * \param wsi: lws connection
3900 * Not normally needed since it's passed into the callback
3902 LWS_VISIBLE LWS_EXTERN void *
3903 lws_wsi_user(struct lws *wsi);
3906 * lws_parse_uri: cut up prot:/ads:port/path into pieces
3907 * Notice it does so by dropping '\0' into input string
3908 * and the leading / on the path is consequently lost
3910 * \param p: incoming uri string.. will get written to
3911 * \param prot: result pointer for protocol part (https://)
3912 * \param ads: result pointer for address part
3913 * \param port: result pointer for port part
3914 * \param path: result pointer for path part
3916 LWS_VISIBLE LWS_EXTERN int LWS_WARN_UNUSED_RESULT
3917 lws_parse_uri(char *p, const char **prot, const char **ads, int *port,
3921 * lws_now_secs(): return seconds since 1970-1-1
3923 LWS_VISIBLE LWS_EXTERN unsigned long
3927 * lws_get_context - Allow geting lws_context from a Websocket connection
3930 * With this function, users can access context in the callback function.
3931 * Otherwise users may have to declare context as a global variable.
3933 * \param wsi: Websocket connection instance
3935 LWS_VISIBLE LWS_EXTERN struct lws_context * LWS_WARN_UNUSED_RESULT
3936 lws_get_context(const struct lws *wsi);
3939 * lws_get_count_threads(): how many service threads the context uses
3941 * \param context: the lws context
3943 * By default this is always 1, if you asked for more than lws can handle it
3944 * will clip the number of threads. So you can use this to find out how many
3945 * threads are actually in use.
3947 LWS_VISIBLE LWS_EXTERN int LWS_WARN_UNUSED_RESULT
3948 lws_get_count_threads(struct lws_context *context);
3951 * lws_get_parent() - get parent wsi or NULL
3952 * \param wsi: lws connection
3954 * Specialized wsi like cgi stdin/out/err are associated to a parent wsi,
3955 * this allows you to get their parent.
3957 LWS_VISIBLE LWS_EXTERN struct lws * LWS_WARN_UNUSED_RESULT
3958 lws_get_parent(const struct lws *wsi);
3961 * lws_get_child() - get child wsi or NULL
3962 * \param wsi: lws connection
3964 * Allows you to find a related wsi from the parent wsi.
3966 LWS_VISIBLE LWS_EXTERN struct lws * LWS_WARN_UNUSED_RESULT
3967 lws_get_child(const struct lws *wsi);
3971 * \deprecated DEPRECATED Note: this is not normally needed as a user api.
3972 * It's provided in case it is
3973 * useful when integrating with other app poll loop service code.
3975 LWS_VISIBLE LWS_EXTERN int
3976 lws_read(struct lws *wsi, unsigned char *buf, size_t len);
3979 * lws_set_allocator() - custom allocator support
3983 * Allows you to replace the allocator (and deallocator) used by lws
3985 LWS_VISIBLE LWS_EXTERN void
3986 lws_set_allocator(void *(*realloc)(void *ptr, size_t size));
3989 /** \defgroup wsstatus Websocket status APIs
3990 * ##Websocket connection status APIs
3992 * These provide information about ws connection or message status
3996 * lws_send_pipe_choked() - tests if socket is writable or not
3997 * \param wsi: lws connection
3999 * Allows you to check if you can write more on the socket
4001 LWS_VISIBLE LWS_EXTERN int LWS_WARN_UNUSED_RESULT
4002 lws_send_pipe_choked(struct lws *wsi);
4005 * lws_is_final_fragment() - tests if last part of ws message
4006 * \param wsi: lws connection
4008 LWS_VISIBLE LWS_EXTERN int
4009 lws_is_final_fragment(struct lws *wsi);
4012 * lws_get_reserved_bits() - access reserved bits of ws frame
4013 * \param wsi: lws connection
4015 LWS_VISIBLE LWS_EXTERN unsigned char
4016 lws_get_reserved_bits(struct lws *wsi);
4019 * lws_partial_buffered() - find out if lws buffered the last write
4020 * \param wsi: websocket connection to check
4022 * Returns 1 if you cannot use lws_write because the last
4023 * write on this connection is still buffered, and can't be cleared without
4024 * returning to the service loop and waiting for the connection to be
4027 * If you will try to do >1 lws_write call inside a single
4028 * WRITEABLE callback, you must check this after every write and bail if
4029 * set, ask for a new writeable callback and continue writing from there.
4031 * This is never set at the start of a writeable callback, but any write
4034 LWS_VISIBLE LWS_EXTERN int LWS_WARN_UNUSED_RESULT
4035 lws_partial_buffered(struct lws *wsi);
4038 * lws_frame_is_binary(): true if the current frame was sent in binary mode
4040 * \param wsi: the connection we are inquiring about
4042 * This is intended to be called from the LWS_CALLBACK_RECEIVE callback if
4043 * it's interested to see if the frame it's dealing with was sent in binary
4046 LWS_VISIBLE LWS_EXTERN int LWS_WARN_UNUSED_RESULT
4047 lws_frame_is_binary(struct lws *wsi);
4050 * lws_is_ssl() - Find out if connection is using SSL
4051 * \param wsi: websocket connection to check
4053 * Returns 0 if the connection is not using SSL, 1 if using SSL and
4054 * using verified cert, and 2 if using SSL but the cert was not
4055 * checked (appears for client wsi told to skip check on connection)
4057 LWS_VISIBLE LWS_EXTERN int
4058 lws_is_ssl(struct lws *wsi);
4060 * lws_is_cgi() - find out if this wsi is running a cgi process
4061 * \param wsi: lws connection
4063 LWS_VISIBLE LWS_EXTERN int
4064 lws_is_cgi(struct lws *wsi);
4066 #ifdef LWS_OPENSSL_SUPPORT
4068 * lws_get_ssl() - Return wsi's SSL context structure
4069 * \param wsi: websocket connection
4071 * Returns pointer to the SSL library's context structure
4073 LWS_VISIBLE LWS_EXTERN SSL*
4074 lws_get_ssl(struct lws *wsi);
4079 /** \defgroup sha SHA and B64 helpers
4080 * ##SHA and B64 helpers
4082 * These provide SHA-1 and B64 helper apis
4085 #ifdef LWS_SHA1_USE_OPENSSL_NAME
4086 #define lws_SHA1 SHA1
4089 * lws_SHA1(): make a SHA-1 digest of a buffer
4091 * \param d: incoming buffer
4092 * \param n: length of incoming buffer
4093 * \param md: buffer for message digest (must be >= 20 bytes)
4095 * Reduces any size buffer into a 20-byte SHA-1 hash.
4097 LWS_VISIBLE LWS_EXTERN unsigned char *
4098 lws_SHA1(const unsigned char *d, size_t n, unsigned char *md);
4101 * lws_b64_encode_string(): encode a string into base 64
4103 * \param in: incoming buffer
4104 * \param in_len: length of incoming buffer
4105 * \param out: result buffer
4106 * \param out_size: length of result buffer
4108 * Encodes a string using b64
4110 LWS_VISIBLE LWS_EXTERN int
4111 lws_b64_encode_string(const char *in, int in_len, char *out, int out_size);
4113 * lws_b64_decode_string(): decode a string from base 64
4115 * \param in: incoming buffer
4116 * \param out: result buffer
4117 * \param out_size: length of result buffer
4119 * Decodes a string using b64
4121 LWS_VISIBLE LWS_EXTERN int
4122 lws_b64_decode_string(const char *in, char *out, int out_size);
4126 /*! \defgroup cgi cgi handling
4130 * These functions allow low-level control over stdin/out/err of the cgi.
4132 * However for most cases, binding the cgi to http in and out, the default
4133 * lws implementation already does the right thing.
4136 enum lws_enum_stdinouterr {
4142 enum lws_cgi_hdr_state {
4152 struct lws_cgi_args {
4153 struct lws **stdwsi; /**< get fd with lws_get_socket_fd() */
4154 enum lws_enum_stdinouterr ch; /**< channel index */
4155 unsigned char *data; /**< for messages with payload */
4156 enum lws_cgi_hdr_state hdr_state; /**< track where we are in cgi headers */
4157 int len; /**< length */
4162 * lws_cgi: spawn network-connected cgi process
4164 * \param wsi: connection to own the process
4165 * \param exec_array: array of "exec-name" "arg1" ... "argn" NULL
4166 * \param script_uri_path_len: how many chars on the left of the uri are the path to the cgi
4167 * \param timeout_secs: seconds script should be allowed to run
4168 * \param mp_cgienv: pvo list with per-vhost cgi options to put in env
4170 LWS_VISIBLE LWS_EXTERN int
4171 lws_cgi(struct lws *wsi, const char * const *exec_array,
4172 int script_uri_path_len, int timeout_secs,
4173 const struct lws_protocol_vhost_options *mp_cgienv);
4176 * lws_cgi_write_split_stdout_headers: write cgi output accounting for header part
4178 * \param wsi: connection to own the process
4180 LWS_VISIBLE LWS_EXTERN int
4181 lws_cgi_write_split_stdout_headers(struct lws *wsi);
4184 * lws_cgi_kill: terminate cgi process associated with wsi
4186 * \param wsi: connection to own the process
4188 LWS_VISIBLE LWS_EXTERN int
4189 lws_cgi_kill(struct lws *wsi);
4194 /*! \defgroup fops file operation wrapping
4196 * ##File operation wrapping
4198 * Use these helper functions if you want to access a file from the perspective
4199 * of a specific wsi, which is usually the case. If you just want contextless
4200 * file access, use the fops callbacks directly with NULL wsi instead of these
4203 * If so, then it calls the platform handler or user overrides where present
4204 * (as defined in info->fops)
4206 * The advantage from all this is user code can be portable for file operations
4207 * without having to deal with differences between platforms.
4211 /** struct lws_plat_file_ops - Platform-specific file operations
4213 * These provide platform-agnostic ways to deal with filesystem access in the
4214 * library and in the user code.
4217 #if defined(LWS_WITH_ESP32)
4218 /* sdk preprocessor defs? compiler issue? gets confused with member names */
4219 #define LWS_FOP_OPEN _open
4220 #define LWS_FOP_CLOSE _close
4221 #define LWS_FOP_SEEK_CUR _seek_cur
4222 #define LWS_FOP_READ _read
4223 #define LWS_FOP_WRITE _write
4225 #define LWS_FOP_OPEN open
4226 #define LWS_FOP_CLOSE close
4227 #define LWS_FOP_SEEK_CUR seek_cur
4228 #define LWS_FOP_READ read
4229 #define LWS_FOP_WRITE write
4232 #define LWS_FOP_FLAGS_MASK ((1 << 23) - 1)
4233 #define LWS_FOP_FLAG_COMPR_ACCEPTABLE_GZIP (1 << 24)
4234 #define LWS_FOP_FLAG_COMPR_IS_GZIP (1 << 25)
4236 struct lws_plat_file_ops {
4237 lws_filefd_type (*LWS_FOP_OPEN)(struct lws *wsi, const char *filename,
4238 unsigned long *filelen, int *flags);
4239 /**< Open file (always binary access if plat supports it)
4240 * filelen is filled on exit to be the length of the file
4241 * *flags & LWS_FOP_FLAGS_MASK should be set to O_RDONLY or O_RDWR.
4242 * If the file may be gzip-compressed,
4243 * LWS_FOP_FLAG_COMPR_ACCEPTABLE_GZIP is set. If it actually is
4244 * gzip-compressed, then the open handler should OR
4245 * LWS_FOP_FLAG_COMPR_IS_GZIP on to *flags before returning.
4247 int (*LWS_FOP_CLOSE)(struct lws *wsi, lws_filefd_type fd);
4249 unsigned long (*LWS_FOP_SEEK_CUR)(struct lws *wsi, lws_filefd_type fd,
4250 long offset_from_cur_pos);
4251 /**< seek from current position */
4252 int (*LWS_FOP_READ)(struct lws *wsi, lws_filefd_type fd,
4253 unsigned long *amount, unsigned char *buf,
4255 /**< Read from file, on exit *amount is set to amount actually read */
4256 int (*LWS_FOP_WRITE)(struct lws *wsi, lws_filefd_type fd,
4257 unsigned long *amount, unsigned char *buf,
4259 /**< Write to file, on exit *amount is set to amount actually written */
4261 /* Add new things just above here ---^
4262 * This is part of the ABI, don't needlessly break compatibility */
4266 * lws_get_fops() - get current file ops
4268 * \param context: context
4270 LWS_VISIBLE LWS_EXTERN struct lws_plat_file_ops * LWS_WARN_UNUSED_RESULT
4271 lws_get_fops(struct lws_context *context);
4272 LWS_VISIBLE LWS_EXTERN void
4273 lws_set_fops(struct lws_context *context, struct lws_plat_file_ops *fops);
4275 * lws_plat_file_open() - file open operations
4277 * \param wsi: connection doing the opening
4278 * \param filename: filename to open
4279 * \param filelen: length of file (filled in by call)
4280 * \param flags: open flags
4282 static LWS_INLINE lws_filefd_type LWS_WARN_UNUSED_RESULT
4283 lws_plat_file_open(struct lws *wsi, const char *filename,
4284 unsigned long *filelen, int *flags)
4286 return lws_get_fops(lws_get_context(wsi))->LWS_FOP_OPEN(wsi, filename,
4291 * lws_plat_file_close() - close file
4293 * \param wsi: connection opened by
4294 * \param fd: file descriptor
4296 static LWS_INLINE int
4297 lws_plat_file_close(struct lws *wsi, lws_filefd_type fd)
4299 return lws_get_fops(lws_get_context(wsi))->LWS_FOP_CLOSE(wsi, fd);
4303 * lws_plat_file_seek_cur() - close file
4305 * \param wsi: connection opened by
4306 * \param fd: file descriptor
4307 * \param offset: position to seek to
4309 static LWS_INLINE unsigned long
4310 lws_plat_file_seek_cur(struct lws *wsi, lws_filefd_type fd, long offset)
4312 return lws_get_fops(lws_get_context(wsi))->LWS_FOP_SEEK_CUR(wsi,
4316 * lws_plat_file_read() - read from file
4318 * \param wsi: connection opened by
4319 * \param fd: file descriptor
4320 * \param amount: how much to read (rewritten by call)
4321 * \param buf: buffer to write to
4322 * \param len: max length
4324 static LWS_INLINE int LWS_WARN_UNUSED_RESULT
4325 lws_plat_file_read(struct lws *wsi, lws_filefd_type fd, unsigned long *amount,
4326 unsigned char *buf, unsigned long len)
4328 return lws_get_fops(lws_get_context(wsi))->LWS_FOP_READ(wsi, fd,
4332 * lws_plat_file_write() - write from file
4334 * \param wsi: connection opened by
4335 * \param fd: file descriptor
4336 * \param amount: how much to write (rewritten by call)
4337 * \param buf: buffer to read from
4338 * \param len: max length
4340 static LWS_INLINE int LWS_WARN_UNUSED_RESULT
4341 lws_plat_file_write(struct lws *wsi, lws_filefd_type fd, unsigned long *amount,
4342 unsigned char *buf, unsigned long len)
4344 return lws_get_fops(lws_get_context(wsi))->LWS_FOP_WRITE(wsi, fd,
4351 * ##SMTP related functions
4353 * These apis let you communicate with a local SMTP server to send email from
4354 * lws. It handles all the SMTP sequencing and protocol actions.
4356 * Your system should have postfix, sendmail or another MTA listening on port
4357 * 25 and able to send email using the "mail" commandline app. Usually distro
4358 * MTAs are configured for this by default.
4360 * It runs via its own libuv events if initialized (which requires giving it
4361 * a libuv loop to attach to).
4363 * It operates using three callbacks, on_next() queries if there is a new email
4364 * to send, on_get_body() asks for the body of the email, and on_sent() is
4365 * called after the email is successfully sent.
4369 * - create an lws_email struct
4371 * - initialize data, loop, the email_* strings, max_content_size and
4374 * - call lws_email_init()
4376 * When you have at least one email to send, call lws_email_check() to
4377 * schedule starting to send it.
4380 #ifdef LWS_WITH_SMTP
4382 /** enum lwsgs_smtp_states - where we are in SMTP protocol sequence */
4383 enum lwsgs_smtp_states {
4384 LGSSMTP_IDLE, /**< awaiting new email */
4385 LGSSMTP_CONNECTING, /**< opening tcp connection to MTA */
4386 LGSSMTP_CONNECTED, /**< tcp connection to MTA is connected */
4387 LGSSMTP_SENT_HELO, /**< sent the HELO */
4388 LGSSMTP_SENT_FROM, /**< sent FROM */
4389 LGSSMTP_SENT_TO, /**< sent TO */
4390 LGSSMTP_SENT_DATA, /**< sent DATA request */
4391 LGSSMTP_SENT_BODY, /**< sent the email body */
4392 LGSSMTP_SENT_QUIT, /**< sent the session quit */
4395 /** struct lws_email - abstract context for performing SMTP operations */
4398 /**< opaque pointer set by user code and available to the callbacks */
4400 /**< the libuv loop we will work on */
4402 char email_smtp_ip[32]; /**< Fill before init, eg, "127.0.0.1" */
4403 char email_helo[32]; /**< Fill before init, eg, "myserver.com" */
4404 char email_from[100]; /**< Fill before init or on_next */
4405 char email_to[100]; /**< Fill before init or on_next */
4407 unsigned int max_content_size;
4408 /**< largest possible email body size */
4410 /* Fill all the callbacks before init */
4412 int (*on_next)(struct lws_email *email);
4413 /**< (Fill in before calling lws_email_init)
4414 * called when idle, 0 = another email to send, nonzero is idle.
4415 * If you return 0, all of the email_* char arrays must be set
4416 * to something useful. */
4417 int (*on_sent)(struct lws_email *email);
4418 /**< (Fill in before calling lws_email_init)
4419 * called when transfer of the email to the SMTP server was
4420 * successful, your callback would remove the current email
4422 int (*on_get_body)(struct lws_email *email, char *buf, int len);
4423 /**< (Fill in before calling lws_email_init)
4424 * called when the body part of the queued email is about to be
4425 * sent to the SMTP server. */
4428 /* private things */
4429 uv_timer_t timeout_email; /**< private */
4430 enum lwsgs_smtp_states estate; /**< private */
4431 uv_connect_t email_connect_req; /**< private */
4432 uv_tcp_t email_client; /**< private */
4433 time_t email_connect_started; /**< private */
4434 char email_buf[256]; /**< private */
4435 char *content; /**< private */
4439 * lws_email_init() - Initialize a struct lws_email
4441 * \param email: struct lws_email to init
4442 * \param loop: libuv loop to use
4443 * \param max_content: max email content size
4445 * Prepares a struct lws_email for use ending SMTP
4447 LWS_VISIBLE LWS_EXTERN int
4448 lws_email_init(struct lws_email *email, uv_loop_t *loop, int max_content);
4451 * lws_email_check() - Request check for new email
4453 * \param email: struct lws_email context to check
4455 * Schedules a check for new emails in 1s... call this when you have queued an
4458 LWS_VISIBLE LWS_EXTERN void
4459 lws_email_check(struct lws_email *email);
4461 * lws_email_destroy() - stop using the struct lws_email
4463 * \param email: the struct lws_email context
4465 * Stop sending email using email and free allocations
4467 LWS_VISIBLE LWS_EXTERN void
4468 lws_email_destroy(struct lws_email *email);