3 /***************************************************************************
5 * Project ___| | | | _ \| |
7 * | (__| |_| | _ <| |___
8 * \___|\___/|_| \_\_____|
10 * Copyright (C) 1998 - 2006, Daniel Stenberg, <daniel@haxx.se>, et al.
12 * This software is licensed as described in the file COPYING, which
13 * you should have received as part of this distribution. The terms
14 * are also available at http://curl.haxx.se/docs/copyright.html.
16 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
17 * copies of the Software, and permit persons to whom the Software is
18 * furnished to do so, under the terms of the COPYING file.
20 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
21 * KIND, either express or implied.
24 ***************************************************************************/
26 This is an "external" header file. Don't give away any internals here!
30 o Enable a "pull" interface. The application that uses libcurl decides where
31 and when to ask libcurl to get/send data.
33 o Enable multiple simultaneous transfers in the same thread without making it
34 complicated for the application.
36 o Enable the application to select() on its own file descriptors and curl's
37 file descriptors simultaneous easily.
40 #if defined(_WIN32) && !defined(WIN32)
41 /* Chris Lewis mentioned that he doesn't get WIN32 defined, only _WIN32 so we
42 make this adjustment to catch this. */
46 #if defined(WIN32) && !defined(_WIN32_WCE) && !defined(__GNUC__) && \
47 !defined(__CYGWIN__) || defined(__MINGW32__)
48 #if !(defined(_WINSOCKAPI_) || defined(_WINSOCK_H))
49 /* The check above prevents the winsock2 inclusion if winsock.h already was
50 included, since they can't co-exist without problems */
55 /* HP-UX systems version 9, 10 and 11 lack sys/select.h and so does oldish
56 libc5-based Linux systems. Only include it on system that are known to
58 #if defined(_AIX) || defined(NETWARE) || defined(__NetBSD__) || defined(_MINIX)
59 #include <sys/select.h>
63 #include <sys/socket.h>
66 #include <sys/types.h>
70 * This header file should not really need to include "curl.h" since curl.h
71 * itself includes this file and we expect user applications to do #include
72 * <curl/curl.h> without the need for especially including multi.h.
74 * For some reason we added this include here at one point, and rather than to
75 * break existing (wrongly written) libcurl applications, we leave it as-is
76 * but with this warning attached.
86 #ifndef curl_socket_typedef
87 /* Public socket typedef */
89 typedef SOCKET curl_socket_t;
90 #define CURL_SOCKET_BAD INVALID_SOCKET
92 typedef int curl_socket_t;
93 #define CURL_SOCKET_BAD -1
95 #define curl_socket_typedef
96 #endif /* curl_socket_typedef */
99 CURLM_CALL_MULTI_PERFORM = -1, /* please call curl_multi_perform() or
100 curl_multi_socket*() soon */
102 CURLM_BAD_HANDLE, /* the passed-in handle is not a valid CURLM handle */
103 CURLM_BAD_EASY_HANDLE, /* an easy handle was not good/valid */
104 CURLM_OUT_OF_MEMORY, /* if you ever get this, you're in deep sh*t */
105 CURLM_INTERNAL_ERROR, /* this is a libcurl bug */
106 CURLM_BAD_SOCKET, /* the passed in socket argument did not match */
107 CURLM_UNKNOWN_OPTION, /* curl_multi_setopt() with unsupported option */
111 /* just to make code nicer when using curl_multi_socket() you can now check
112 for CURLM_CALL_MULTI_SOCKET too in the same style it works for
113 curl_multi_perform() and CURLM_CALL_MULTI_PERFORM */
114 #define CURLM_CALL_MULTI_SOCKET CURLM_CALL_MULTI_PERFORM
117 CURLMSG_NONE, /* first, not used */
118 CURLMSG_DONE, /* This easy handle has completed. 'result' contains
119 the CURLcode of the transfer */
120 CURLMSG_LAST /* last, not used */
124 CURLMSG msg; /* what this message means */
125 CURL *easy_handle; /* the handle it concerns */
127 void *whatever; /* message-specific data */
128 CURLcode result; /* return code for transfer */
131 typedef struct CURLMsg CURLMsg;
134 * Name: curl_multi_init()
136 * Desc: inititalize multi-style curl usage
138 * Returns: a new CURLM handle to use in all 'curl_multi' functions.
140 CURL_EXTERN CURLM *curl_multi_init(void);
143 * Name: curl_multi_add_handle()
145 * Desc: add a standard curl handle to the multi stack
147 * Returns: CURLMcode type, general multi error code.
149 CURL_EXTERN CURLMcode curl_multi_add_handle(CURLM *multi_handle,
153 * Name: curl_multi_remove_handle()
155 * Desc: removes a curl handle from the multi stack again
157 * Returns: CURLMcode type, general multi error code.
159 CURL_EXTERN CURLMcode curl_multi_remove_handle(CURLM *multi_handle,
163 * Name: curl_multi_fdset()
165 * Desc: Ask curl for its fd_set sets. The app can use these to select() or
166 * poll() on. We want curl_multi_perform() called as soon as one of
169 * Returns: CURLMcode type, general multi error code.
171 CURL_EXTERN CURLMcode curl_multi_fdset(CURLM *multi_handle,
173 fd_set *write_fd_set,
178 * Name: curl_multi_perform()
180 * Desc: When the app thinks there's data available for curl it calls this
181 * function to read/write whatever there is right now. This returns
182 * as soon as the reads and writes are done. This function does not
183 * require that there actually is data available for reading or that
184 * data can be written, it can be called just in case. It returns
185 * the number of handles that still transfer data in the second
186 * argument's integer-pointer.
188 * Returns: CURLMcode type, general multi error code. *NOTE* that this only
189 * returns errors etc regarding the whole multi stack. There might
190 * still have occurred problems on invidual transfers even when this
193 CURL_EXTERN CURLMcode curl_multi_perform(CURLM *multi_handle,
194 int *running_handles);
197 * Name: curl_multi_cleanup()
199 * Desc: Cleans up and removes a whole multi stack. It does not free or
200 * touch any individual easy handles in any way. We need to define
201 * in what state those handles will be if this function is called
202 * in the middle of a transfer.
204 * Returns: CURLMcode type, general multi error code.
206 CURL_EXTERN CURLMcode curl_multi_cleanup(CURLM *multi_handle);
209 * Name: curl_multi_info_read()
211 * Desc: Ask the multi handle if there's any messages/informationals from
212 * the individual transfers. Messages include informationals such as
213 * error code from the transfer or just the fact that a transfer is
214 * completed. More details on these should be written down as well.
216 * Repeated calls to this function will return a new struct each
217 * time, until a special "end of msgs" struct is returned as a signal
218 * that there is no more to get at this point.
220 * The data the returned pointer points to will not survive calling
221 * curl_multi_cleanup().
223 * The 'CURLMsg' struct is meant to be very simple and only contain
224 * very basic informations. If more involved information is wanted,
225 * we will provide the particular "transfer handle" in that struct
226 * and that should/could/would be used in subsequent
227 * curl_easy_getinfo() calls (or similar). The point being that we
228 * must never expose complex structs to applications, as then we'll
229 * undoubtably get backwards compatibility problems in the future.
231 * Returns: A pointer to a filled-in struct, or NULL if it failed or ran out
232 * of structs. It also writes the number of messages left in the
233 * queue (after this read) in the integer the second argument points
236 CURL_EXTERN CURLMsg *curl_multi_info_read(CURLM *multi_handle,
240 * Name: curl_multi_strerror()
242 * Desc: The curl_multi_strerror function may be used to turn a CURLMcode
243 * value into the equivalent human readable error string. This is
244 * useful for printing meaningful error messages.
246 * Returns: A pointer to a zero-terminated error message.
248 CURL_EXTERN const char *curl_multi_strerror(CURLMcode);
251 * Name: curl_multi_socket() and
252 * curl_multi_socket_all()
254 * Desc: An alternative version of curl_multi_perform() that allows the
255 * application to pass in one of the file descriptors that have been
256 * detected to have "action" on them and let libcurl perform.
257 * See man page for details.
259 #define CURL_POLL_NONE 0
260 #define CURL_POLL_IN 1
261 #define CURL_POLL_OUT 2
262 #define CURL_POLL_INOUT 3
263 #define CURL_POLL_REMOVE 4
265 #define CURL_SOCKET_TIMEOUT CURL_SOCKET_BAD
267 typedef int (*curl_socket_callback)(CURL *easy, /* easy handle */
268 curl_socket_t s, /* socket */
269 int what, /* see above */
270 void *userp, /* private callback
272 void *socketp); /* private socket
275 CURL_EXTERN CURLMcode curl_multi_socket(CURLM *multi_handle, curl_socket_t s,
276 int *running_handles);
278 CURL_EXTERN CURLMcode curl_multi_socket_all(CURLM *multi_handle,
279 int *running_handles);
282 * Name: curl_multi_timeout()
284 * Desc: Returns the maximum number of milliseconds the app is allowed to
285 * wait before curl_multi_socket() or curl_multi_perform() must be
286 * called (to allow libcurl's timed events to take place).
288 * Returns: CURLM error code.
290 CURL_EXTERN CURLMcode curl_multi_timeout(CURLM *multi_handle,
293 #undef CINIT /* re-using the same name as in curl.h */
296 #define CINIT(name,type,number) CURLMOPT_ ## name = CURLOPTTYPE_ ## type + number
298 /* The macro "##" is ISO C, we assume pre-ISO C doesn't support it. */
299 #define LONG CURLOPTTYPE_LONG
300 #define OBJECTPOINT CURLOPTTYPE_OBJECTPOINT
301 #define FUNCTIONPOINT CURLOPTTYPE_FUNCTIONPOINT
302 #define OFF_T CURLOPTTYPE_OFF_T
303 #define CINIT(name,type,number) CURLMOPT_/**/name = type + number
307 /* This is the socket callback function pointer */
308 CINIT(SOCKETFUNCTION, FUNCTIONPOINT, 1),
310 /* This is the argument passed to the socket callback */
311 CINIT(SOCKETDATA, OBJECTPOINT, 2),
313 CURLMOPT_LASTENTRY /* the last unused */
318 * Name: curl_multi_setopt()
320 * Desc: Sets options for the multi handle.
322 * Returns: CURLM error code.
324 CURL_EXTERN CURLMcode curl_multi_setopt(CURLM *multi_handle,
325 CURLMoption option, ...);
329 * Name: curl_multi_assign()
331 * Desc: This function sets an association in the multi handle between the
332 * given socket and a private pointer of the application. This is
333 * (only) useful for curl_multi_socket uses.
335 * Returns: CURLM error code.
337 CURL_EXTERN CURLMcode curl_multi_assign(CURLM *multi_handle,
338 curl_socket_t sockfd, void *sockp);
341 } /* end of extern "C" */