http.c

   1 #include "git-compat-util.h"
   2 #include "http.h"
   3 #include "pack.h"
   4 #include "sideband.h"
   5 #include "run-command.h"
   6 #include "url.h"
   7 #include "urlmatch.h"
   8 #include "credential.h"
   9 #include "version.h"
  10 #include "pkt-line.h"
  11 #include "gettext.h"
  12 #include "transport.h"
  13
  14 int active_requests;
  15 int http_is_verbose;
  16 size_t http_post_buffer = 16 * LARGE_PACKET_MAX;
  17
  18 #if LIBCURL_VERSION_NUM >= 0x070a06
  19 #define LIBCURL_CAN_HANDLE_AUTH_ANY
  20 #endif
  21
  22 static int min_curl_sessions = 1;
  23 static int curl_session_count;
  24 #ifdef USE_CURL_MULTI
  25 static int max_requests = -1;
  26 static CURLM *curlm;
  27 #endif
  28 #ifndef NO_CURL_EASY_DUPHANDLE
  29 static CURL *curl_default;
  30 #endif
  31
  32 #define PREV_BUF_SIZE 4096
  33 #define RANGE_HEADER_SIZE 30
  34
  35 char curl_errorstr[CURL_ERROR_SIZE];
  36
  37 static int curl_ssl_verify = -1;
  38 static int curl_ssl_try;
  39 static const char *ssl_cert;
  40 #if LIBCURL_VERSION_NUM >= 0x070903
  41 static const char *ssl_key;
  42 #endif
  43 #if LIBCURL_VERSION_NUM >= 0x070908
  44 static const char *ssl_capath;
  45 #endif
  46 static const char *ssl_cainfo;
  47 static long curl_low_speed_limit = -1;
  48 static long curl_low_speed_time = -1;
  49 static int curl_ftp_no_epsv;
  50 static const char *curl_http_proxy;
  51 static const char *curl_cookie_file;
  52 static int curl_save_cookies;
  53 struct credential http_auth = CREDENTIAL_INIT;
  54 static int http_proactive_auth;
  55 static const char *user_agent;
  56
  57 #if LIBCURL_VERSION_NUM >= 0x071700
  58 /* Use CURLOPT_KEYPASSWD as is */
  59 #elif LIBCURL_VERSION_NUM >= 0x070903
  60 #define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
  61 #else
  62 #define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
  63 #endif
  64
  65 static struct credential cert_auth = CREDENTIAL_INIT;
  66 static int ssl_cert_password_required;
  67 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
  68 static unsigned long http_auth_methods = CURLAUTH_ANY;
  69 #endif
  70
  71 static struct curl_slist *pragma_header;
  72 static struct curl_slist *no_pragma_header;
  73
  74 static struct active_request_slot *active_queue_head;
  75
  76 static char *cached_accept_language;
  77
  78 size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
  79 {
  80         size_t size = eltsize * nmemb;
  81         struct buffer *buffer = buffer_;
  82
  83         if (size > buffer->buf.len - buffer->posn)
  84                 size = buffer->buf.len - buffer->posn;
  85         memcpy(ptr, buffer->buf.buf + buffer->posn, size);
  86         buffer->posn += size;
  87
  88         return size;
  89 }
  90
  91 #ifndef NO_CURL_IOCTL
  92 curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
  93 {
  94         struct buffer *buffer = clientp;
  95
  96         switch (cmd) {
  97         case CURLIOCMD_NOP:
  98                 return CURLIOE_OK;
  99
 100         case CURLIOCMD_RESTARTREAD:
 101                 buffer->posn = 0;
 102                 return CURLIOE_OK;
 103
 104         default:
 105                 return CURLIOE_UNKNOWNCMD;
 106         }
 107 }
 108 #endif
 109
 110 size_t fwrite_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
 111 {
 112         size_t size = eltsize * nmemb;
 113         struct strbuf *buffer = buffer_;
 114
 115         strbuf_add(buffer, ptr, size);
 116         return size;
 117 }
 118
 119 size_t fwrite_null(char *ptr, size_t eltsize, size_t nmemb, void *strbuf)
 120 {
 121         return eltsize * nmemb;
 122 }
 123
 124 static void closedown_active_slot(struct active_request_slot *slot)
 125 {
 126         active_requests--;
 127         slot->in_use = 0;
 128 }
 129
 130 static void finish_active_slot(struct active_request_slot *slot)
 131 {
 132         closedown_active_slot(slot);
 133         curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
 134
 135         if (slot->finished != NULL)
 136                 (*slot->finished) = 1;
 137
 138         /* Store slot results so they can be read after the slot is reused */
 139         if (slot->results != NULL) {
 140                 slot->results->curl_result = slot->curl_result;
 141                 slot->results->http_code = slot->http_code;
 142 #if LIBCURL_VERSION_NUM >= 0x070a08
 143                 curl_easy_getinfo(slot->curl, CURLINFO_HTTPAUTH_AVAIL,
 144                                   &slot->results->auth_avail);
 145 #else
 146                 slot->results->auth_avail = 0;
 147 #endif
 148         }
 149
 150         /* Run callback if appropriate */
 151         if (slot->callback_func != NULL)
 152                 slot->callback_func(slot->callback_data);
 153 }
 154
 155 #ifdef USE_CURL_MULTI
 156 static void process_curl_messages(void)
 157 {
 158         int num_messages;
 159         struct active_request_slot *slot;
 160         CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
 161
 162         while (curl_message != NULL) {
 163                 if (curl_message->msg == CURLMSG_DONE) {
 164                         int curl_result = curl_message->data.result;
 165                         slot = active_queue_head;
 166                         while (slot != NULL &&
 167                                slot->curl != curl_message->easy_handle)
 168                                 slot = slot->next;
 169                         if (slot != NULL) {
 170                                 curl_multi_remove_handle(curlm, slot->curl);
 171                                 slot->curl_result = curl_result;
 172                                 finish_active_slot(slot);
 173                         } else {
 174                                 fprintf(stderr, "Received DONE message for unknown request!\n");
 175                         }
 176                 } else {
 177                         fprintf(stderr, "Unknown CURL message received: %d\n",
 178                                 (int)curl_message->msg);
 179                 }
 180                 curl_message = curl_multi_info_read(curlm, &num_messages);
 181         }
 182 }
 183 #endif
 184
 185 static int http_options(const char *var, const char *value, void *cb)
 186 {
 187         if (!strcmp("http.sslverify", var)) {
 188                 curl_ssl_verify = git_config_bool(var, value);
 189                 return 0;
 190         }
 191         if (!strcmp("http.sslcert", var))
 192                 return git_config_string(&ssl_cert, var, value);
 193 #if LIBCURL_VERSION_NUM >= 0x070903
 194         if (!strcmp("http.sslkey", var))
 195                 return git_config_string(&ssl_key, var, value);
 196 #endif
 197 #if LIBCURL_VERSION_NUM >= 0x070908
 198         if (!strcmp("http.sslcapath", var))
 199                 return git_config_string(&ssl_capath, var, value);
 200 #endif
 201         if (!strcmp("http.sslcainfo", var))
 202                 return git_config_string(&ssl_cainfo, var, value);
 203         if (!strcmp("http.sslcertpasswordprotected", var)) {
 204                 ssl_cert_password_required = git_config_bool(var, value);
 205                 return 0;
 206         }
 207         if (!strcmp("http.ssltry", var)) {
 208                 curl_ssl_try = git_config_bool(var, value);
 209                 return 0;
 210         }
 211         if (!strcmp("http.minsessions", var)) {
 212                 min_curl_sessions = git_config_int(var, value);
 213 #ifndef USE_CURL_MULTI
 214                 if (min_curl_sessions > 1)
 215                         min_curl_sessions = 1;
 216 #endif
 217                 return 0;
 218         }
 219 #ifdef USE_CURL_MULTI
 220         if (!strcmp("http.maxrequests", var)) {
 221                 max_requests = git_config_int(var, value);
 222                 return 0;
 223         }
 224 #endif
 225         if (!strcmp("http.lowspeedlimit", var)) {
 226                 curl_low_speed_limit = (long)git_config_int(var, value);
 227                 return 0;
 228         }
 229         if (!strcmp("http.lowspeedtime", var)) {
 230                 curl_low_speed_time = (long)git_config_int(var, value);
 231                 return 0;
 232         }
 233
 234         if (!strcmp("http.noepsv", var)) {
 235                 curl_ftp_no_epsv = git_config_bool(var, value);
 236                 return 0;
 237         }
 238         if (!strcmp("http.proxy", var))
 239                 return git_config_string(&curl_http_proxy, var, value);
 240
 241         if (!strcmp("http.cookiefile", var))
 242                 return git_config_string(&curl_cookie_file, var, value);
 243         if (!strcmp("http.savecookies", var)) {
 244                 curl_save_cookies = git_config_bool(var, value);
 245                 return 0;
 246         }
 247
 248         if (!strcmp("http.postbuffer", var)) {
 249                 http_post_buffer = git_config_int(var, value);
 250                 if (http_post_buffer < LARGE_PACKET_MAX)
 251                         http_post_buffer = LARGE_PACKET_MAX;
 252                 return 0;
 253         }
 254
 255         if (!strcmp("http.useragent", var))
 256                 return git_config_string(&user_agent, var, value);
 257
 258         /* Fall back on the default ones */
 259         return git_default_config(var, value, cb);
 260 }
 261
 262 static void init_curl_http_auth(CURL *result)
 263 {
 264         if (!http_auth.username)
 265                 return;
 266
 267         credential_fill(&http_auth);
 268
 269 #if LIBCURL_VERSION_NUM >= 0x071301
 270         curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username);
 271         curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password);
 272 #else
 273         {
 274                 static struct strbuf up = STRBUF_INIT;
 275                 /*
 276                  * Note that we assume we only ever have a single set of
 277                  * credentials in a given program run, so we do not have
 278                  * to worry about updating this buffer, only setting its
 279                  * initial value.
 280                  */
 281                 if (!up.len)
 282                         strbuf_addf(&up, "%s:%s",
 283                                 http_auth.username, http_auth.password);
 284                 curl_easy_setopt(result, CURLOPT_USERPWD, up.buf);
 285         }
 286 #endif
 287 }
 288
 289 static int has_cert_password(void)
 290 {
 291         if (ssl_cert == NULL || ssl_cert_password_required != 1)
 292                 return 0;
 293         if (!cert_auth.password) {
 294                 cert_auth.protocol = xstrdup("cert");
 295                 cert_auth.username = xstrdup("");
 296                 cert_auth.path = xstrdup(ssl_cert);
 297                 credential_fill(&cert_auth);
 298         }
 299         return 1;
 300 }
 301
 302 #if LIBCURL_VERSION_NUM >= 0x071900
 303 static void set_curl_keepalive(CURL *c)
 304 {
 305         curl_easy_setopt(c, CURLOPT_TCP_KEEPALIVE, 1);
 306 }
 307
 308 #elif LIBCURL_VERSION_NUM >= 0x071000
 309 static int sockopt_callback(void *client, curl_socket_t fd, curlsocktype type)
 310 {
 311         int ka = 1;
 312         int rc;
 313         socklen_t len = (socklen_t)sizeof(ka);
 314
 315         if (type != CURLSOCKTYPE_IPCXN)
 316                 return 0;
 317
 318         rc = setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&ka, len);
 319         if (rc < 0)
 320                 warning("unable to set SO_KEEPALIVE on socket %s",
 321                         strerror(errno));
 322
 323         return 0; /* CURL_SOCKOPT_OK only exists since curl 7.21.5 */
 324 }
 325
 326 static void set_curl_keepalive(CURL *c)
 327 {
 328         curl_easy_setopt(c, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
 329 }
 330
 331 #else
 332 static void set_curl_keepalive(CURL *c)
 333 {
 334         /* not supported on older curl versions */
 335 }
 336 #endif
 337
 338 static CURL *get_curl_handle(void)
 339 {
 340         CURL *result = curl_easy_init();
 341         long allowed_protocols = 0;
 342
 343         if (!result)
 344                 die("curl_easy_init failed");
 345
 346         if (!curl_ssl_verify) {
 347                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
 348                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
 349         } else {
 350                 /* Verify authenticity of the peer's certificate */
 351                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
 352                 /* The name in the cert must match whom we tried to connect */
 353                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
 354         }
 355
 356 #if LIBCURL_VERSION_NUM >= 0x070907
 357         curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
 358 #endif
 359 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 360         curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 361 #endif
 362
 363         if (http_proactive_auth)
 364                 init_curl_http_auth(result);
 365
 366         if (ssl_cert != NULL)
 367                 curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
 368         if (has_cert_password())
 369                 curl_easy_setopt(result, CURLOPT_KEYPASSWD, cert_auth.password);
 370 #if LIBCURL_VERSION_NUM >= 0x070903
 371         if (ssl_key != NULL)
 372                 curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
 373 #endif
 374 #if LIBCURL_VERSION_NUM >= 0x070908
 375         if (ssl_capath != NULL)
 376                 curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
 377 #endif
 378         if (ssl_cainfo != NULL)
 379                 curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
 380
 381         if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
 382                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
 383                                  curl_low_speed_limit);
 384                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
 385                                  curl_low_speed_time);
 386         }
 387
 388         curl_easy_setopt(result, CURLOPT_FOLLOWLOCATION, 1);
 389         curl_easy_setopt(result, CURLOPT_MAXREDIRS, 20);
 390 #if LIBCURL_VERSION_NUM >= 0x071301
 391         curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
 392 #elif LIBCURL_VERSION_NUM >= 0x071101
 393         curl_easy_setopt(result, CURLOPT_POST301, 1);
 394 #endif
 395 #if LIBCURL_VERSION_NUM >= 0x071304
 396         if (is_transport_allowed("http"))
 397                 allowed_protocols |= CURLPROTO_HTTP;
 398         if (is_transport_allowed("https"))
 399                 allowed_protocols |= CURLPROTO_HTTPS;
 400         if (is_transport_allowed("ftp"))
 401                 allowed_protocols |= CURLPROTO_FTP;
 402         if (is_transport_allowed("ftps"))
 403                 allowed_protocols |= CURLPROTO_FTPS;
 404         curl_easy_setopt(result, CURLOPT_REDIR_PROTOCOLS, allowed_protocols);
 405 #else
 406         if (transport_restrict_protocols())
 407                 warning("protocol restrictions not applied to curl redirects because\n"
 408                         "your curl version is too old (>= 7.19.4)");
 409 #endif
 410
 411         if (getenv("GIT_CURL_VERBOSE"))
 412                 curl_easy_setopt(result, CURLOPT_VERBOSE, 1);
 413
 414         curl_easy_setopt(result, CURLOPT_USERAGENT,
 415                 user_agent ? user_agent : git_user_agent());
 416
 417         if (curl_ftp_no_epsv)
 418                 curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
 419
 420 #ifdef CURLOPT_USE_SSL
 421         if (curl_ssl_try)
 422                 curl_easy_setopt(result, CURLOPT_USE_SSL, CURLUSESSL_TRY);
 423 #endif
 424
 425         if (curl_http_proxy) {
 426                 curl_easy_setopt(result, CURLOPT_PROXY, curl_http_proxy);
 427         }
 428 #if LIBCURL_VERSION_NUM >= 0x070a07
 429         curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 430 #endif
 431
 432         set_curl_keepalive(result);
 433
 434         return result;
 435 }
 436
 437 static void set_from_env(const char **var, const char *envname)
 438 {
 439         const char *val = getenv(envname);
 440         if (val)
 441                 *var = val;
 442 }
 443
 444 void http_init(struct remote *remote, const char *url, int proactive_auth)
 445 {
 446         char *low_speed_limit;
 447         char *low_speed_time;
 448         char *normalized_url;
 449         struct urlmatch_config config = { STRING_LIST_INIT_DUP };
 450
 451         config.section = "http";
 452         config.key = NULL;
 453         config.collect_fn = http_options;
 454         config.cascade_fn = git_default_config;
 455         config.cb = NULL;
 456
 457         http_is_verbose = 0;
 458         normalized_url = url_normalize(url, &config.url);
 459
 460         git_config(urlmatch_config_entry, &config);
 461         free(normalized_url);
 462
 463         if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK)
 464                 die("curl_global_init failed");
 465
 466         http_proactive_auth = proactive_auth;
 467
 468         if (remote && remote->http_proxy)
 469                 curl_http_proxy = xstrdup(remote->http_proxy);
 470
 471         pragma_header = curl_slist_append(pragma_header, "Pragma: no-cache");
 472         no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
 473
 474 #ifdef USE_CURL_MULTI
 475         {
 476                 char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
 477                 if (http_max_requests != NULL)
 478                         max_requests = atoi(http_max_requests);
 479         }
 480
 481         curlm = curl_multi_init();
 482         if (!curlm)
 483                 die("curl_multi_init failed");
 484 #endif
 485
 486         if (getenv("GIT_SSL_NO_VERIFY"))
 487                 curl_ssl_verify = 0;
 488
 489         set_from_env(&ssl_cert, "GIT_SSL_CERT");
 490 #if LIBCURL_VERSION_NUM >= 0x070903
 491         set_from_env(&ssl_key, "GIT_SSL_KEY");
 492 #endif
 493 #if LIBCURL_VERSION_NUM >= 0x070908
 494         set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
 495 #endif
 496         set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
 497
 498         set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
 499
 500         low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
 501         if (low_speed_limit != NULL)
 502                 curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
 503         low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
 504         if (low_speed_time != NULL)
 505                 curl_low_speed_time = strtol(low_speed_time, NULL, 10);
 506
 507         if (curl_ssl_verify == -1)
 508                 curl_ssl_verify = 1;
 509
 510         curl_session_count = 0;
 511 #ifdef USE_CURL_MULTI
 512         if (max_requests < 1)
 513                 max_requests = DEFAULT_MAX_REQUESTS;
 514 #endif
 515
 516         if (getenv("GIT_CURL_FTP_NO_EPSV"))
 517                 curl_ftp_no_epsv = 1;
 518
 519         if (url) {
 520                 credential_from_url(&http_auth, url);
 521                 if (!ssl_cert_password_required &&
 522                     getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
 523                     starts_with(url, "https://"))
 524                         ssl_cert_password_required = 1;
 525         }
 526
 527 #ifndef NO_CURL_EASY_DUPHANDLE
 528         curl_default = get_curl_handle();
 529 #endif
 530 }
 531
 532 void http_cleanup(void)
 533 {
 534         struct active_request_slot *slot = active_queue_head;
 535
 536         while (slot != NULL) {
 537                 struct active_request_slot *next = slot->next;
 538                 if (slot->curl != NULL) {
 539 #ifdef USE_CURL_MULTI
 540                         curl_multi_remove_handle(curlm, slot->curl);
 541 #endif
 542                         curl_easy_cleanup(slot->curl);
 543                 }
 544                 free(slot);
 545                 slot = next;
 546         }
 547         active_queue_head = NULL;
 548
 549 #ifndef NO_CURL_EASY_DUPHANDLE
 550         curl_easy_cleanup(curl_default);
 551 #endif
 552
 553 #ifdef USE_CURL_MULTI
 554         curl_multi_cleanup(curlm);
 555 #endif
 556         curl_global_cleanup();
 557
 558         curl_slist_free_all(pragma_header);
 559         pragma_header = NULL;
 560
 561         curl_slist_free_all(no_pragma_header);
 562         no_pragma_header = NULL;
 563
 564         if (curl_http_proxy) {
 565                 free((void *)curl_http_proxy);
 566                 curl_http_proxy = NULL;
 567         }
 568
 569         if (cert_auth.password != NULL) {
 570                 memset(cert_auth.password, 0, strlen(cert_auth.password));
 571                 free(cert_auth.password);
 572                 cert_auth.password = NULL;
 573         }
 574         ssl_cert_password_required = 0;
 575
 576         free(cached_accept_language);
 577         cached_accept_language = NULL;
 578 }
 579
 580 struct active_request_slot *get_active_slot(void)
 581 {
 582         struct active_request_slot *slot = active_queue_head;
 583         struct active_request_slot *newslot;
 584
 585 #ifdef USE_CURL_MULTI
 586         int num_transfers;
 587
 588         /* Wait for a slot to open up if the queue is full */
 589         while (active_requests >= max_requests) {
 590                 curl_multi_perform(curlm, &num_transfers);
 591                 if (num_transfers < active_requests)
 592                         process_curl_messages();
 593         }
 594 #endif
 595
 596         while (slot != NULL && slot->in_use)
 597                 slot = slot->next;
 598
 599         if (slot == NULL) {
 600                 newslot = xmalloc(sizeof(*newslot));
 601                 newslot->curl = NULL;
 602                 newslot->in_use = 0;
 603                 newslot->next = NULL;
 604
 605                 slot = active_queue_head;
 606                 if (slot == NULL) {
 607                         active_queue_head = newslot;
 608                 } else {
 609                         while (slot->next != NULL)
 610                                 slot = slot->next;
 611                         slot->next = newslot;
 612                 }
 613                 slot = newslot;
 614         }
 615
 616         if (slot->curl == NULL) {
 617 #ifdef NO_CURL_EASY_DUPHANDLE
 618                 slot->curl = get_curl_handle();
 619 #else
 620                 slot->curl = curl_easy_duphandle(curl_default);
 621 #endif
 622                 curl_session_count++;
 623         }
 624
 625         active_requests++;
 626         slot->in_use = 1;
 627         slot->results = NULL;
 628         slot->finished = NULL;
 629         slot->callback_data = NULL;
 630         slot->callback_func = NULL;
 631         curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
 632         if (curl_save_cookies)
 633                 curl_easy_setopt(slot->curl, CURLOPT_COOKIEJAR, curl_cookie_file);
 634         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
 635         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
 636         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
 637         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
 638         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
 639         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
 640         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
 641         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 642         curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 1);
 643 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 644         curl_easy_setopt(slot->curl, CURLOPT_HTTPAUTH, http_auth_methods);
 645 #endif
 646         if (http_auth.password)
 647                 init_curl_http_auth(slot->curl);
 648
 649         return slot;
 650 }
 651
 652 int start_active_slot(struct active_request_slot *slot)
 653 {
 654 #ifdef USE_CURL_MULTI
 655         CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
 656         int num_transfers;
 657
 658         if (curlm_result != CURLM_OK &&
 659             curlm_result != CURLM_CALL_MULTI_PERFORM) {
 660                 active_requests--;
 661                 slot->in_use = 0;
 662                 return 0;
 663         }
 664
 665         /*
 666          * We know there must be something to do, since we just added
 667          * something.
 668          */
 669         curl_multi_perform(curlm, &num_transfers);
 670 #endif
 671         return 1;
 672 }
 673
 674 #ifdef USE_CURL_MULTI
 675 struct fill_chain {
 676         void *data;
 677         int (*fill)(void *);
 678         struct fill_chain *next;
 679 };
 680
 681 static struct fill_chain *fill_cfg;
 682
 683 void add_fill_function(void *data, int (*fill)(void *))
 684 {
 685         struct fill_chain *new = xmalloc(sizeof(*new));
 686         struct fill_chain **linkp = &fill_cfg;
 687         new->data = data;
 688         new->fill = fill;
 689         new->next = NULL;
 690         while (*linkp)
 691                 linkp = &(*linkp)->next;
 692         *linkp = new;
 693 }
 694
 695 void fill_active_slots(void)
 696 {
 697         struct active_request_slot *slot = active_queue_head;
 698
 699         while (active_requests < max_requests) {
 700                 struct fill_chain *fill;
 701                 for (fill = fill_cfg; fill; fill = fill->next)
 702                         if (fill->fill(fill->data))
 703                                 break;
 704
 705                 if (!fill)
 706                         break;
 707         }
 708
 709         while (slot != NULL) {
 710                 if (!slot->in_use && slot->curl != NULL
 711                         && curl_session_count > min_curl_sessions) {
 712                         curl_easy_cleanup(slot->curl);
 713                         slot->curl = NULL;
 714                         curl_session_count--;
 715                 }
 716                 slot = slot->next;
 717         }
 718 }
 719
 720 void step_active_slots(void)
 721 {
 722         int num_transfers;
 723         CURLMcode curlm_result;
 724
 725         do {
 726                 curlm_result = curl_multi_perform(curlm, &num_transfers);
 727         } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
 728         if (num_transfers < active_requests) {
 729                 process_curl_messages();
 730                 fill_active_slots();
 731         }
 732 }
 733 #endif
 734
 735 void run_active_slot(struct active_request_slot *slot)
 736 {
 737 #ifdef USE_CURL_MULTI
 738         fd_set readfds;
 739         fd_set writefds;
 740         fd_set excfds;
 741         int max_fd;
 742         struct timeval select_timeout;
 743         int finished = 0;
 744
 745         slot->finished = &finished;
 746         while (!finished) {
 747                 step_active_slots();
 748
 749                 if (slot->in_use) {
 750 #if LIBCURL_VERSION_NUM >= 0x070f04
 751                         long curl_timeout;
 752                         curl_multi_timeout(curlm, &curl_timeout);
 753                         if (curl_timeout == 0) {
 754                                 continue;
 755                         } else if (curl_timeout == -1) {
 756                                 select_timeout.tv_sec  = 0;
 757                                 select_timeout.tv_usec = 50000;
 758                         } else {
 759                                 select_timeout.tv_sec  =  curl_timeout / 1000;
 760                                 select_timeout.tv_usec = (curl_timeout % 1000) * 1000;
 761                         }
 762 #else
 763                         select_timeout.tv_sec  = 0;
 764                         select_timeout.tv_usec = 50000;
 765 #endif
 766
 767                         max_fd = -1;
 768                         FD_ZERO(&readfds);
 769                         FD_ZERO(&writefds);
 770                         FD_ZERO(&excfds);
 771                         curl_multi_fdset(curlm, &readfds, &writefds, &excfds, &max_fd);
 772
 773                         /*
 774                          * It can happen that curl_multi_timeout returns a pathologically
 775                          * long timeout when curl_multi_fdset returns no file descriptors
 776                          * to read.  See commit message for more details.
 777                          */
 778                         if (max_fd < 0 &&
 779                             (select_timeout.tv_sec > 0 ||
 780                              select_timeout.tv_usec > 50000)) {
 781                                 select_timeout.tv_sec  = 0;
 782                                 select_timeout.tv_usec = 50000;
 783                         }
 784
 785                         select(max_fd+1, &readfds, &writefds, &excfds, &select_timeout);
 786                 }
 787         }
 788 #else
 789         while (slot->in_use) {
 790                 slot->curl_result = curl_easy_perform(slot->curl);
 791                 finish_active_slot(slot);
 792         }
 793 #endif
 794 }
 795
 796 static void release_active_slot(struct active_request_slot *slot)
 797 {
 798         closedown_active_slot(slot);
 799         if (slot->curl && curl_session_count > min_curl_sessions) {
 800 #ifdef USE_CURL_MULTI
 801                 curl_multi_remove_handle(curlm, slot->curl);
 802 #endif
 803                 curl_easy_cleanup(slot->curl);
 804                 slot->curl = NULL;
 805                 curl_session_count--;
 806         }
 807 #ifdef USE_CURL_MULTI
 808         fill_active_slots();
 809 #endif
 810 }
 811
 812 void finish_all_active_slots(void)
 813 {
 814         struct active_request_slot *slot = active_queue_head;
 815
 816         while (slot != NULL)
 817                 if (slot->in_use) {
 818                         run_active_slot(slot);
 819                         slot = active_queue_head;
 820                 } else {
 821                         slot = slot->next;
 822                 }
 823 }
 824
 825 /* Helpers for modifying and creating URLs */
 826 static inline int needs_quote(int ch)
 827 {
 828         if (((ch >= 'A') && (ch <= 'Z'))
 829                         || ((ch >= 'a') && (ch <= 'z'))
 830                         || ((ch >= '0') && (ch <= '9'))
 831                         || (ch == '/')
 832                         || (ch == '-')
 833                         || (ch == '.'))
 834                 return 0;
 835         return 1;
 836 }
 837
 838 static char *quote_ref_url(const char *base, const char *ref)
 839 {
 840         struct strbuf buf = STRBUF_INIT;
 841         const char *cp;
 842         int ch;
 843
 844         end_url_with_slash(&buf, base);
 845
 846         for (cp = ref; (ch = *cp) != 0; cp++)
 847                 if (needs_quote(ch))
 848                         strbuf_addf(&buf, "%%%02x", ch);
 849                 else
 850                         strbuf_addch(&buf, *cp);
 851
 852         return strbuf_detach(&buf, NULL);
 853 }
 854
 855 void append_remote_object_url(struct strbuf *buf, const char *url,
 856                               const char *hex,
 857                               int only_two_digit_prefix)
 858 {
 859         end_url_with_slash(buf, url);
 860
 861         strbuf_addf(buf, "objects/%.*s/", 2, hex);
 862         if (!only_two_digit_prefix)
 863                 strbuf_addf(buf, "%s", hex+2);
 864 }
 865
 866 char *get_remote_object_url(const char *url, const char *hex,
 867                             int only_two_digit_prefix)
 868 {
 869         struct strbuf buf = STRBUF_INIT;
 870         append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
 871         return strbuf_detach(&buf, NULL);
 872 }
 873
 874 static int handle_curl_result(struct slot_results *results)
 875 {
 876         /*
 877          * If we see a failing http code with CURLE_OK, we have turned off
 878          * FAILONERROR (to keep the server's custom error response), and should
 879          * translate the code into failure here.
 880          */
 881         if (results->curl_result == CURLE_OK &&
 882             results->http_code >= 400) {
 883                 results->curl_result = CURLE_HTTP_RETURNED_ERROR;
 884                 /*
 885                  * Normally curl will already have put the "reason phrase"
 886                  * from the server into curl_errorstr; unfortunately without
 887                  * FAILONERROR it is lost, so we can give only the numeric
 888                  * status code.
 889                  */
 890                 snprintf(curl_errorstr, sizeof(curl_errorstr),
 891                          "The requested URL returned error: %ld",
 892                          results->http_code);
 893         }
 894
 895         if (results->curl_result == CURLE_OK) {
 896                 credential_approve(&http_auth);
 897                 return HTTP_OK;
 898         } else if (missing_target(results))
 899                 return HTTP_MISSING_TARGET;
 900         else if (results->http_code == 401) {
 901                 if (http_auth.username && http_auth.password) {
 902                         credential_reject(&http_auth);
 903                         return HTTP_NOAUTH;
 904                 } else {
 905 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 906                         http_auth_methods &= ~CURLAUTH_GSSNEGOTIATE;
 907 #endif
 908                         return HTTP_REAUTH;
 909                 }
 910         } else {
 911 #if LIBCURL_VERSION_NUM >= 0x070c00
 912                 if (!curl_errorstr[0])
 913                         strlcpy(curl_errorstr,
 914                                 curl_easy_strerror(results->curl_result),
 915                                 sizeof(curl_errorstr));
 916 #endif
 917                 return HTTP_ERROR;
 918         }
 919 }
 920
 921 int run_one_slot(struct active_request_slot *slot,
 922                  struct slot_results *results)
 923 {
 924         slot->results = results;
 925         if (!start_active_slot(slot)) {
 926                 snprintf(curl_errorstr, sizeof(curl_errorstr),
 927                          "failed to start HTTP request");
 928                 return HTTP_START_FAILED;
 929         }
 930
 931         run_active_slot(slot);
 932         return handle_curl_result(results);
 933 }
 934
 935 static CURLcode curlinfo_strbuf(CURL *curl, CURLINFO info, struct strbuf *buf)
 936 {
 937         char *ptr;
 938         CURLcode ret;
 939
 940         strbuf_reset(buf);
 941         ret = curl_easy_getinfo(curl, info, &ptr);
 942         if (!ret && ptr)
 943                 strbuf_addstr(buf, ptr);
 944         return ret;
 945 }
 946
 947 /*
 948  * Check for and extract a content-type parameter. "raw"
 949  * should be positioned at the start of the potential
 950  * parameter, with any whitespace already removed.
 951  *
 952  * "name" is the name of the parameter. The value is appended
 953  * to "out".
 954  */
 955 static int extract_param(const char *raw, const char *name,
 956                          struct strbuf *out)
 957 {
 958         size_t len = strlen(name);
 959
 960         if (strncasecmp(raw, name, len))
 961                 return -1;
 962         raw += len;
 963
 964         if (*raw != '=')
 965                 return -1;
 966         raw++;
 967
 968         while (*raw && !isspace(*raw) && *raw != ';')
 969                 strbuf_addch(out, *raw++);
 970         return 0;
 971 }
 972
 973 /*
 974  * Extract a normalized version of the content type, with any
 975  * spaces suppressed, all letters lowercased, and no trailing ";"
 976  * or parameters.
 977  *
 978  * Note that we will silently remove even invalid whitespace. For
 979  * example, "text / plain" is specifically forbidden by RFC 2616,
 980  * but "text/plain" is the only reasonable output, and this keeps
 981  * our code simple.
 982  *
 983  * If the "charset" argument is not NULL, store the value of any
 984  * charset parameter there.
 985  *
 986  * Example:
 987  *   "TEXT/PLAIN; charset=utf-8" -> "text/plain", "utf-8"
 988  *   "text / plain" -> "text/plain"
 989  */
 990 static void extract_content_type(struct strbuf *raw, struct strbuf *type,
 991                                  struct strbuf *charset)
 992 {
 993         const char *p;
 994
 995         strbuf_reset(type);
 996         strbuf_grow(type, raw->len);
 997         for (p = raw->buf; *p; p++) {
 998                 if (isspace(*p))
 999                         continue;
1000                 if (*p == ';') {
1001                         p++;
1002                         break;
1003                 }
1004                 strbuf_addch(type, tolower(*p));
1005         }
1006
1007         if (!charset)
1008                 return;
1009
1010         strbuf_reset(charset);
1011         while (*p) {
1012                 while (isspace(*p) || *p == ';')
1013                         p++;
1014                 if (!extract_param(p, "charset", charset))
1015                         return;
1016                 while (*p && !isspace(*p))
1017                         p++;
1018         }
1019
1020         if (!charset->len && starts_with(type->buf, "text/"))
1021                 strbuf_addstr(charset, "ISO-8859-1");
1022 }
1023
1024 static void write_accept_language(struct strbuf *buf)
1025 {
1026         /*
1027          * MAX_DECIMAL_PLACES must not be larger than 3. If it is larger than
1028          * that, q-value will be smaller than 0.001, the minimum q-value the
1029          * HTTP specification allows. See
1030          * http://tools.ietf.org/html/rfc7231#section-5.3.1 for q-value.
1031          */
1032         const int MAX_DECIMAL_PLACES = 3;
1033         const int MAX_LANGUAGE_TAGS = 1000;
1034         const int MAX_ACCEPT_LANGUAGE_HEADER_SIZE = 4000;
1035         char **language_tags = NULL;
1036         int num_langs = 0;
1037         const char *s = get_preferred_languages();
1038         int i;
1039         struct strbuf tag = STRBUF_INIT;
1040
1041         /* Don't add Accept-Language header if no language is preferred. */
1042         if (!s)
1043                 return;
1044
1045         /*
1046          * Split the colon-separated string of preferred languages into
1047          * language_tags array.
1048          */
1049         do {
1050                 /* collect language tag */
1051                 for (; *s && (isalnum(*s) || *s == '_'); s++)
1052                         strbuf_addch(&tag, *s == '_' ? '-' : *s);
1053
1054                 /* skip .codeset, @modifier and any other unnecessary parts */
1055                 while (*s && *s != ':')
1056                         s++;
1057
1058                 if (tag.len) {
1059                         num_langs++;
1060                         REALLOC_ARRAY(language_tags, num_langs);
1061                         language_tags[num_langs - 1] = strbuf_detach(&tag, NULL);
1062                         if (num_langs >= MAX_LANGUAGE_TAGS - 1) /* -1 for '*' */
1063                                 break;
1064                 }
1065         } while (*s++);
1066
1067         /* write Accept-Language header into buf */
1068         if (num_langs) {
1069                 int last_buf_len = 0;
1070                 int max_q;
1071                 int decimal_places;
1072                 char q_format[32];
1073
1074                 /* add '*' */
1075                 REALLOC_ARRAY(language_tags, num_langs + 1);
1076                 language_tags[num_langs++] = "*"; /* it's OK; this won't be freed */
1077
1078                 /* compute decimal_places */
1079                 for (max_q = 1, decimal_places = 0;
1080                      max_q < num_langs && decimal_places <= MAX_DECIMAL_PLACES;
1081                      decimal_places++, max_q *= 10)
1082                         ;
1083
1084                 sprintf(q_format, ";q=0.%%0%dd", decimal_places);
1085
1086                 strbuf_addstr(buf, "Accept-Language: ");
1087
1088                 for (i = 0; i < num_langs; i++) {
1089                         if (i > 0)
1090                                 strbuf_addstr(buf, ", ");
1091
1092                         strbuf_addstr(buf, language_tags[i]);
1093
1094                         if (i > 0)
1095                                 strbuf_addf(buf, q_format, max_q - i);
1096
1097                         if (buf->len > MAX_ACCEPT_LANGUAGE_HEADER_SIZE) {
1098                                 strbuf_remove(buf, last_buf_len, buf->len - last_buf_len);
1099                                 break;
1100                         }
1101
1102                         last_buf_len = buf->len;
1103                 }
1104         }
1105
1106         /* free language tags -- last one is a static '*' */
1107         for (i = 0; i < num_langs - 1; i++)
1108                 free(language_tags[i]);
1109         free(language_tags);
1110 }
1111
1112 /*
1113  * Get an Accept-Language header which indicates user's preferred languages.
1114  *
1115  * Examples:
1116  *   LANGUAGE= -> ""
1117  *   LANGUAGE=ko:en -> "Accept-Language: ko, en; q=0.9, *; q=0.1"
1118  *   LANGUAGE=ko_KR.UTF-8:sr@latin -> "Accept-Language: ko-KR, sr; q=0.9, *; q=0.1"
1119  *   LANGUAGE=ko LANG=en_US.UTF-8 -> "Accept-Language: ko, *; q=0.1"
1120  *   LANGUAGE= LANG=en_US.UTF-8 -> "Accept-Language: en-US, *; q=0.1"
1121  *   LANGUAGE= LANG=C -> ""
1122  */
1123 static const char *get_accept_language(void)
1124 {
1125         if (!cached_accept_language) {
1126                 struct strbuf buf = STRBUF_INIT;
1127                 write_accept_language(&buf);
1128                 if (buf.len > 0)
1129                         cached_accept_language = strbuf_detach(&buf, NULL);
1130         }
1131
1132         return cached_accept_language;
1133 }
1134
1135 /* http_request() targets */
1136 #define HTTP_REQUEST_STRBUF     0
1137 #define HTTP_REQUEST_FILE       1
1138
1139 static int http_request(const char *url,
1140                         void *result, int target,
1141                         const struct http_get_options *options)
1142 {
1143         struct active_request_slot *slot;
1144         struct slot_results results;
1145         struct curl_slist *headers = NULL;
1146         struct strbuf buf = STRBUF_INIT;
1147         const char *accept_language;
1148         int ret;
1149
1150         slot = get_active_slot();
1151         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1152
1153         if (result == NULL) {
1154                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
1155         } else {
1156                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
1157                 curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
1158
1159                 if (target == HTTP_REQUEST_FILE) {
1160                         long posn = ftell(result);
1161                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1162                                          fwrite);
1163                         if (posn > 0) {
1164                                 strbuf_addf(&buf, "Range: bytes=%ld-", posn);
1165                                 headers = curl_slist_append(headers, buf.buf);
1166                                 strbuf_reset(&buf);
1167                         }
1168                 } else
1169                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1170                                          fwrite_buffer);
1171         }
1172
1173         accept_language = get_accept_language();
1174
1175         if (accept_language)
1176                 headers = curl_slist_append(headers, accept_language);
1177
1178         strbuf_addstr(&buf, "Pragma:");
1179         if (options && options->no_cache)
1180                 strbuf_addstr(&buf, " no-cache");
1181         if (options && options->keep_error)
1182                 curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
1183
1184         headers = curl_slist_append(headers, buf.buf);
1185
1186         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
1187         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
1188         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "gzip");
1189
1190         ret = run_one_slot(slot, &results);
1191
1192         if (options && options->content_type) {
1193                 struct strbuf raw = STRBUF_INIT;
1194                 curlinfo_strbuf(slot->curl, CURLINFO_CONTENT_TYPE, &raw);
1195                 extract_content_type(&raw, options->content_type,
1196                                      options->charset);
1197                 strbuf_release(&raw);
1198         }
1199
1200         if (options && options->effective_url)
1201                 curlinfo_strbuf(slot->curl, CURLINFO_EFFECTIVE_URL,
1202                                 options->effective_url);
1203
1204         curl_slist_free_all(headers);
1205         strbuf_release(&buf);
1206
1207         return ret;
1208 }
1209
1210 /*
1211  * Update the "base" url to a more appropriate value, as deduced by
1212  * redirects seen when requesting a URL starting with "url".
1213  *
1214  * The "asked" parameter is a URL that we asked curl to access, and must begin
1215  * with "base".
1216  *
1217  * The "got" parameter is the URL that curl reported to us as where we ended
1218  * up.
1219  *
1220  * Returns 1 if we updated the base url, 0 otherwise.
1221  *
1222  * Our basic strategy is to compare "base" and "asked" to find the bits
1223  * specific to our request. We then strip those bits off of "got" to yield the
1224  * new base. So for example, if our base is "http://example.com/foo.git",
1225  * and we ask for "http://example.com/foo.git/info/refs", we might end up
1226  * with "https://other.example.com/foo.git/info/refs". We would want the
1227  * new URL to become "https://other.example.com/foo.git".
1228  *
1229  * Note that this assumes a sane redirect scheme. It's entirely possible
1230  * in the example above to end up at a URL that does not even end in
1231  * "info/refs".  In such a case we simply punt, as there is not much we can
1232  * do (and such a scheme is unlikely to represent a real git repository,
1233  * which means we are likely about to abort anyway).
1234  */
1235 static int update_url_from_redirect(struct strbuf *base,
1236                                     const char *asked,
1237                                     const struct strbuf *got)
1238 {
1239         const char *tail;
1240         size_t tail_len;
1241
1242         if (!strcmp(asked, got->buf))
1243                 return 0;
1244
1245         if (!skip_prefix(asked, base->buf, &tail))
1246                 die("BUG: update_url_from_redirect: %s is not a superset of %s",
1247                     asked, base->buf);
1248
1249         tail_len = strlen(tail);
1250
1251         if (got->len < tail_len ||
1252             strcmp(tail, got->buf + got->len - tail_len))
1253                 return 0; /* insane redirect scheme */
1254
1255         strbuf_reset(base);
1256         strbuf_add(base, got->buf, got->len - tail_len);
1257         return 1;
1258 }
1259
1260 static int http_request_reauth(const char *url,
1261                                void *result, int target,
1262                                struct http_get_options *options)
1263 {
1264         int ret = http_request(url, result, target, options);
1265
1266         if (options && options->effective_url && options->base_url) {
1267                 if (update_url_from_redirect(options->base_url,
1268                                              url, options->effective_url)) {
1269                         credential_from_url(&http_auth, options->base_url->buf);
1270                         url = options->effective_url->buf;
1271                 }
1272         }
1273
1274         if (ret != HTTP_REAUTH)
1275                 return ret;
1276
1277         /*
1278          * If we are using KEEP_ERROR, the previous request may have
1279          * put cruft into our output stream; we should clear it out before
1280          * making our next request. We only know how to do this for
1281          * the strbuf case, but that is enough to satisfy current callers.
1282          */
1283         if (options && options->keep_error) {
1284                 switch (target) {
1285                 case HTTP_REQUEST_STRBUF:
1286                         strbuf_reset(result);
1287                         break;
1288                 default:
1289                         die("BUG: HTTP_KEEP_ERROR is only supported with strbufs");
1290                 }
1291         }
1292
1293         credential_fill(&http_auth);
1294
1295         return http_request(url, result, target, options);
1296 }
1297
1298 int http_get_strbuf(const char *url,
1299                     struct strbuf *result,
1300                     struct http_get_options *options)
1301 {
1302         return http_request_reauth(url, result, HTTP_REQUEST_STRBUF, options);
1303 }
1304
1305 /*
1306  * Downloads a URL and stores the result in the given file.
1307  *
1308  * If a previous interrupted download is detected (i.e. a previous temporary
1309  * file is still around) the download is resumed.
1310  */
1311 static int http_get_file(const char *url, const char *filename,
1312                          struct http_get_options *options)
1313 {
1314         int ret;
1315         struct strbuf tmpfile = STRBUF_INIT;
1316         FILE *result;
1317
1318         strbuf_addf(&tmpfile, "%s.temp", filename);
1319         result = fopen(tmpfile.buf, "a");
1320         if (!result) {
1321                 error("Unable to open local file %s", tmpfile.buf);
1322                 ret = HTTP_ERROR;
1323                 goto cleanup;
1324         }
1325
1326         ret = http_request_reauth(url, result, HTTP_REQUEST_FILE, options);
1327         fclose(result);
1328
1329         if (ret == HTTP_OK && move_temp_to_file(tmpfile.buf, filename))
1330                 ret = HTTP_ERROR;
1331 cleanup:
1332         strbuf_release(&tmpfile);
1333         return ret;
1334 }
1335
1336 int http_fetch_ref(const char *base, struct ref *ref)
1337 {
1338         struct http_get_options options = {0};
1339         char *url;
1340         struct strbuf buffer = STRBUF_INIT;
1341         int ret = -1;
1342
1343         options.no_cache = 1;
1344
1345         url = quote_ref_url(base, ref->name);
1346         if (http_get_strbuf(url, &buffer, &options) == HTTP_OK) {
1347                 strbuf_rtrim(&buffer);
1348                 if (buffer.len == 40)
1349                         ret = get_sha1_hex(buffer.buf, ref->old_sha1);
1350                 else if (starts_with(buffer.buf, "ref: ")) {
1351                         ref->symref = xstrdup(buffer.buf + 5);
1352                         ret = 0;
1353                 }
1354         }
1355
1356         strbuf_release(&buffer);
1357         free(url);
1358         return ret;
1359 }
1360
1361 /* Helpers for fetching packs */
1362 static char *fetch_pack_index(unsigned char *sha1, const char *base_url)
1363 {
1364         char *url, *tmp;
1365         struct strbuf buf = STRBUF_INIT;
1366
1367         if (http_is_verbose)
1368                 fprintf(stderr, "Getting index for pack %s\n", sha1_to_hex(sha1));
1369
1370         end_url_with_slash(&buf, base_url);
1371         strbuf_addf(&buf, "objects/pack/pack-%s.idx", sha1_to_hex(sha1));
1372         url = strbuf_detach(&buf, NULL);
1373
1374         strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(sha1));
1375         tmp = strbuf_detach(&buf, NULL);
1376
1377         if (http_get_file(url, tmp, NULL) != HTTP_OK) {
1378                 error("Unable to get pack index %s", url);
1379                 free(tmp);
1380                 tmp = NULL;
1381         }
1382
1383         free(url);
1384         return tmp;
1385 }
1386
1387 static int fetch_and_setup_pack_index(struct packed_git **packs_head,
1388         unsigned char *sha1, const char *base_url)
1389 {
1390         struct packed_git *new_pack;
1391         char *tmp_idx = NULL;
1392         int ret;
1393
1394         if (has_pack_index(sha1)) {
1395                 new_pack = parse_pack_index(sha1, sha1_pack_index_name(sha1));
1396                 if (!new_pack)
1397                         return -1; /* parse_pack_index() already issued error message */
1398                 goto add_pack;
1399         }
1400
1401         tmp_idx = fetch_pack_index(sha1, base_url);
1402         if (!tmp_idx)
1403                 return -1;
1404
1405         new_pack = parse_pack_index(sha1, tmp_idx);
1406         if (!new_pack) {
1407                 unlink(tmp_idx);
1408                 free(tmp_idx);
1409
1410                 return -1; /* parse_pack_index() already issued error message */
1411         }
1412
1413         ret = verify_pack_index(new_pack);
1414         if (!ret) {
1415                 close_pack_index(new_pack);
1416                 ret = move_temp_to_file(tmp_idx, sha1_pack_index_name(sha1));
1417         }
1418         free(tmp_idx);
1419         if (ret)
1420                 return -1;
1421
1422 add_pack:
1423         new_pack->next = *packs_head;
1424         *packs_head = new_pack;
1425         return 0;
1426 }
1427
1428 int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
1429 {
1430         struct http_get_options options = {0};
1431         int ret = 0, i = 0;
1432         char *url, *data;
1433         struct strbuf buf = STRBUF_INIT;
1434         unsigned char sha1[20];
1435
1436         end_url_with_slash(&buf, base_url);
1437         strbuf_addstr(&buf, "objects/info/packs");
1438         url = strbuf_detach(&buf, NULL);
1439
1440         options.no_cache = 1;
1441         ret = http_get_strbuf(url, &buf, &options);
1442         if (ret != HTTP_OK)
1443                 goto cleanup;
1444
1445         data = buf.buf;
1446         while (i < buf.len) {
1447                 switch (data[i]) {
1448                 case 'P':
1449                         i++;
1450                         if (i + 52 <= buf.len &&
1451                             starts_with(data + i, " pack-") &&
1452                             starts_with(data + i + 46, ".pack\n")) {
1453                                 get_sha1_hex(data + i + 6, sha1);
1454                                 fetch_and_setup_pack_index(packs_head, sha1,
1455                                                       base_url);
1456                                 i += 51;
1457                                 break;
1458                         }
1459                 default:
1460                         while (i < buf.len && data[i] != '\n')
1461                                 i++;
1462                 }
1463                 i++;
1464         }
1465
1466 cleanup:
1467         free(url);
1468         return ret;
1469 }
1470
1471 void release_http_pack_request(struct http_pack_request *preq)
1472 {
1473         if (preq->packfile != NULL) {
1474                 fclose(preq->packfile);
1475                 preq->packfile = NULL;
1476         }
1477         if (preq->range_header != NULL) {
1478                 curl_slist_free_all(preq->range_header);
1479                 preq->range_header = NULL;
1480         }
1481         preq->slot = NULL;
1482         free(preq->url);
1483         free(preq);
1484 }
1485
1486 int finish_http_pack_request(struct http_pack_request *preq)
1487 {
1488         struct packed_git **lst;
1489         struct packed_git *p = preq->target;
1490         char *tmp_idx;
1491         struct child_process ip = CHILD_PROCESS_INIT;
1492         const char *ip_argv[8];
1493
1494         close_pack_index(p);
1495
1496         fclose(preq->packfile);
1497         preq->packfile = NULL;
1498
1499         lst = preq->lst;
1500         while (*lst != p)
1501                 lst = &((*lst)->next);
1502         *lst = (*lst)->next;
1503
1504         tmp_idx = xstrdup(preq->tmpfile);
1505         strcpy(tmp_idx + strlen(tmp_idx) - strlen(".pack.temp"),
1506                ".idx.temp");
1507
1508         ip_argv[0] = "index-pack";
1509         ip_argv[1] = "-o";
1510         ip_argv[2] = tmp_idx;
1511         ip_argv[3] = preq->tmpfile;
1512         ip_argv[4] = NULL;
1513
1514         ip.argv = ip_argv;
1515         ip.git_cmd = 1;
1516         ip.no_stdin = 1;
1517         ip.no_stdout = 1;
1518
1519         if (run_command(&ip)) {
1520                 unlink(preq->tmpfile);
1521                 unlink(tmp_idx);
1522                 free(tmp_idx);
1523                 return -1;
1524         }
1525
1526         unlink(sha1_pack_index_name(p->sha1));
1527
1528         if (move_temp_to_file(preq->tmpfile, sha1_pack_name(p->sha1))
1529          || move_temp_to_file(tmp_idx, sha1_pack_index_name(p->sha1))) {
1530                 free(tmp_idx);
1531                 return -1;
1532         }
1533
1534         install_packed_git(p);
1535         free(tmp_idx);
1536         return 0;
1537 }
1538
1539 struct http_pack_request *new_http_pack_request(
1540         struct packed_git *target, const char *base_url)
1541 {
1542         long prev_posn = 0;
1543         char range[RANGE_HEADER_SIZE];
1544         struct strbuf buf = STRBUF_INIT;
1545         struct http_pack_request *preq;
1546
1547         preq = xcalloc(1, sizeof(*preq));
1548         preq->target = target;
1549
1550         end_url_with_slash(&buf, base_url);
1551         strbuf_addf(&buf, "objects/pack/pack-%s.pack",
1552                 sha1_to_hex(target->sha1));
1553         preq->url = strbuf_detach(&buf, NULL);
1554
1555         snprintf(preq->tmpfile, sizeof(preq->tmpfile), "%s.temp",
1556                 sha1_pack_name(target->sha1));
1557         preq->packfile = fopen(preq->tmpfile, "a");
1558         if (!preq->packfile) {
1559                 error("Unable to open local file %s for pack",
1560                       preq->tmpfile);
1561                 goto abort;
1562         }
1563
1564         preq->slot = get_active_slot();
1565         curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
1566         curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
1567         curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
1568         curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1569                 no_pragma_header);
1570
1571         /*
1572          * If there is data present from a previous transfer attempt,
1573          * resume where it left off
1574          */
1575         prev_posn = ftell(preq->packfile);
1576         if (prev_posn>0) {
1577                 if (http_is_verbose)
1578                         fprintf(stderr,
1579                                 "Resuming fetch of pack %s at byte %ld\n",
1580                                 sha1_to_hex(target->sha1), prev_posn);
1581                 sprintf(range, "Range: bytes=%ld-", prev_posn);
1582                 preq->range_header = curl_slist_append(NULL, range);
1583                 curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1584                         preq->range_header);
1585         }
1586
1587         return preq;
1588
1589 abort:
1590         free(preq->url);
1591         free(preq);
1592         return NULL;
1593 }
1594
1595 /* Helpers for fetching objects (loose) */
1596 static size_t fwrite_sha1_file(char *ptr, size_t eltsize, size_t nmemb,
1597                                void *data)
1598 {
1599         unsigned char expn[4096];
1600         size_t size = eltsize * nmemb;
1601         int posn = 0;
1602         struct http_object_request *freq =
1603                 (struct http_object_request *)data;
1604         do {
1605                 ssize_t retval = xwrite(freq->localfile,
1606                                         (char *) ptr + posn, size - posn);
1607                 if (retval < 0)
1608                         return posn;
1609                 posn += retval;
1610         } while (posn < size);
1611
1612         freq->stream.avail_in = size;
1613         freq->stream.next_in = (void *)ptr;
1614         do {
1615                 freq->stream.next_out = expn;
1616                 freq->stream.avail_out = sizeof(expn);
1617                 freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
1618                 git_SHA1_Update(&freq->c, expn,
1619                                 sizeof(expn) - freq->stream.avail_out);
1620         } while (freq->stream.avail_in && freq->zret == Z_OK);
1621         return size;
1622 }
1623
1624 struct http_object_request *new_http_object_request(const char *base_url,
1625         unsigned char *sha1)
1626 {
1627         char *hex = sha1_to_hex(sha1);
1628         const char *filename;
1629         char prevfile[PATH_MAX];
1630         int prevlocal;
1631         char prev_buf[PREV_BUF_SIZE];
1632         ssize_t prev_read = 0;
1633         long prev_posn = 0;
1634         char range[RANGE_HEADER_SIZE];
1635         struct curl_slist *range_header = NULL;
1636         struct http_object_request *freq;
1637
1638         freq = xcalloc(1, sizeof(*freq));
1639         hashcpy(freq->sha1, sha1);
1640         freq->localfile = -1;
1641
1642         filename = sha1_file_name(sha1);
1643         snprintf(freq->tmpfile, sizeof(freq->tmpfile),
1644                  "%s.temp", filename);
1645
1646         snprintf(prevfile, sizeof(prevfile), "%s.prev", filename);
1647         unlink_or_warn(prevfile);
1648         rename(freq->tmpfile, prevfile);
1649         unlink_or_warn(freq->tmpfile);
1650
1651         if (freq->localfile != -1)
1652                 error("fd leakage in start: %d", freq->localfile);
1653         freq->localfile = open(freq->tmpfile,
1654                                O_WRONLY | O_CREAT | O_EXCL, 0666);
1655         /*
1656          * This could have failed due to the "lazy directory creation";
1657          * try to mkdir the last path component.
1658          */
1659         if (freq->localfile < 0 && errno == ENOENT) {
1660                 char *dir = strrchr(freq->tmpfile, '/');
1661                 if (dir) {
1662                         *dir = 0;
1663                         mkdir(freq->tmpfile, 0777);
1664                         *dir = '/';
1665                 }
1666                 freq->localfile = open(freq->tmpfile,
1667                                        O_WRONLY | O_CREAT | O_EXCL, 0666);
1668         }
1669
1670         if (freq->localfile < 0) {
1671                 error("Couldn't create temporary file %s: %s",
1672                       freq->tmpfile, strerror(errno));
1673                 goto abort;
1674         }
1675
1676         git_inflate_init(&freq->stream);
1677
1678         git_SHA1_Init(&freq->c);
1679
1680         freq->url = get_remote_object_url(base_url, hex, 0);
1681
1682         /*
1683          * If a previous temp file is present, process what was already
1684          * fetched.
1685          */
1686         prevlocal = open(prevfile, O_RDONLY);
1687         if (prevlocal != -1) {
1688                 do {
1689                         prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
1690                         if (prev_read>0) {
1691                                 if (fwrite_sha1_file(prev_buf,
1692                                                      1,
1693                                                      prev_read,
1694                                                      freq) == prev_read) {
1695                                         prev_posn += prev_read;
1696                                 } else {
1697                                         prev_read = -1;
1698                                 }
1699                         }
1700                 } while (prev_read > 0);
1701                 close(prevlocal);
1702         }
1703         unlink_or_warn(prevfile);
1704
1705         /*
1706          * Reset inflate/SHA1 if there was an error reading the previous temp
1707          * file; also rewind to the beginning of the local file.
1708          */
1709         if (prev_read == -1) {
1710                 memset(&freq->stream, 0, sizeof(freq->stream));
1711                 git_inflate_init(&freq->stream);
1712                 git_SHA1_Init(&freq->c);
1713                 if (prev_posn>0) {
1714                         prev_posn = 0;
1715                         lseek(freq->localfile, 0, SEEK_SET);
1716                         if (ftruncate(freq->localfile, 0) < 0) {
1717                                 error("Couldn't truncate temporary file %s: %s",
1718                                           freq->tmpfile, strerror(errno));
1719                                 goto abort;
1720                         }
1721                 }
1722         }
1723
1724         freq->slot = get_active_slot();
1725
1726         curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
1727         curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
1728         curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
1729         curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
1730         curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
1731
1732         /*
1733          * If we have successfully processed data from a previous fetch
1734          * attempt, only fetch the data we don't already have.
1735          */
1736         if (prev_posn>0) {
1737                 if (http_is_verbose)
1738                         fprintf(stderr,
1739                                 "Resuming fetch of object %s at byte %ld\n",
1740                                 hex, prev_posn);
1741                 sprintf(range, "Range: bytes=%ld-", prev_posn);
1742                 range_header = curl_slist_append(range_header, range);
1743                 curl_easy_setopt(freq->slot->curl,
1744                                  CURLOPT_HTTPHEADER, range_header);
1745         }
1746
1747         return freq;
1748
1749 abort:
1750         free(freq->url);
1751         free(freq);
1752         return NULL;
1753 }
1754
1755 void process_http_object_request(struct http_object_request *freq)
1756 {
1757         if (freq->slot == NULL)
1758                 return;
1759         freq->curl_result = freq->slot->curl_result;
1760         freq->http_code = freq->slot->http_code;
1761         freq->slot = NULL;
1762 }
1763
1764 int finish_http_object_request(struct http_object_request *freq)
1765 {
1766         struct stat st;
1767
1768         close(freq->localfile);
1769         freq->localfile = -1;
1770
1771         process_http_object_request(freq);
1772
1773         if (freq->http_code == 416) {
1774                 warning("requested range invalid; we may already have all the data.");
1775         } else if (freq->curl_result != CURLE_OK) {
1776                 if (stat(freq->tmpfile, &st) == 0)
1777                         if (st.st_size == 0)
1778                                 unlink_or_warn(freq->tmpfile);
1779                 return -1;
1780         }
1781
1782         git_inflate_end(&freq->stream);
1783         git_SHA1_Final(freq->real_sha1, &freq->c);
1784         if (freq->zret != Z_STREAM_END) {
1785                 unlink_or_warn(freq->tmpfile);
1786                 return -1;
1787         }
1788         if (hashcmp(freq->sha1, freq->real_sha1)) {
1789                 unlink_or_warn(freq->tmpfile);
1790                 return -1;
1791         }
1792         freq->rename =
1793                 move_temp_to_file(freq->tmpfile, sha1_file_name(freq->sha1));
1794
1795         return freq->rename;
1796 }
1797
1798 void abort_http_object_request(struct http_object_request *freq)
1799 {
1800         unlink_or_warn(freq->tmpfile);
1801
1802         release_http_object_request(freq);
1803 }
1804
1805 void release_http_object_request(struct http_object_request *freq)
1806 {
1807         if (freq->localfile != -1) {
1808                 close(freq->localfile);
1809                 freq->localfile = -1;
1810         }
1811         if (freq->url != NULL) {
1812                 free(freq->url);
1813                 freq->url = NULL;
1814         }
1815         if (freq->slot != NULL) {
1816                 freq->slot->callback_func = NULL;
1817                 freq->slot->callback_data = NULL;
1818                 release_active_slot(freq->slot);
1819                 freq->slot = NULL;
1820         }
1821 }