http.c

   1 #include "http.h"
   2 #include "pack.h"
   3
   4 int data_received;
   5 int active_requests;
   6 int http_is_verbose;
   7
   8 #ifdef USE_CURL_MULTI
   9 static int max_requests = -1;
  10 static CURLM *curlm;
  11 #endif
  12 #ifndef NO_CURL_EASY_DUPHANDLE
  13 static CURL *curl_default;
  14 #endif
  15 char curl_errorstr[CURL_ERROR_SIZE];
  16
  17 static int curl_ssl_verify = -1;
  18 static const char *ssl_cert;
  19 #if LIBCURL_VERSION_NUM >= 0x070902
  20 static const char *ssl_key;
  21 #endif
  22 #if LIBCURL_VERSION_NUM >= 0x070908
  23 static const char *ssl_capath;
  24 #endif
  25 static const char *ssl_cainfo;
  26 static long curl_low_speed_limit = -1;
  27 static long curl_low_speed_time = -1;
  28 static int curl_ftp_no_epsv;
  29 static const char *curl_http_proxy;
  30 static char *user_name, *user_pass;
  31
  32 static struct curl_slist *pragma_header;
  33
  34 struct curl_slist *no_pragma_header;
  35
  36 static struct active_request_slot *active_queue_head;
  37
  38 size_t fread_buffer(void *ptr, size_t eltsize, size_t nmemb, void *buffer_)
  39 {
  40         size_t size = eltsize * nmemb;
  41         struct buffer *buffer = buffer_;
  42
  43         if (size > buffer->buf.len - buffer->posn)
  44                 size = buffer->buf.len - buffer->posn;
  45         memcpy(ptr, buffer->buf.buf + buffer->posn, size);
  46         buffer->posn += size;
  47
  48         return size;
  49 }
  50
  51 #ifndef NO_CURL_IOCTL
  52 curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
  53 {
  54         struct buffer *buffer = clientp;
  55
  56         switch (cmd) {
  57         case CURLIOCMD_NOP:
  58                 return CURLIOE_OK;
  59
  60         case CURLIOCMD_RESTARTREAD:
  61                 buffer->posn = 0;
  62                 return CURLIOE_OK;
  63
  64         default:
  65                 return CURLIOE_UNKNOWNCMD;
  66         }
  67 }
  68 #endif
  69
  70 size_t fwrite_buffer(const void *ptr, size_t eltsize, size_t nmemb, void *buffer_)
  71 {
  72         size_t size = eltsize * nmemb;
  73         struct strbuf *buffer = buffer_;
  74
  75         strbuf_add(buffer, ptr, size);
  76         data_received++;
  77         return size;
  78 }
  79
  80 size_t fwrite_null(const void *ptr, size_t eltsize, size_t nmemb, void *strbuf)
  81 {
  82         data_received++;
  83         return eltsize * nmemb;
  84 }
  85
  86 static void finish_active_slot(struct active_request_slot *slot);
  87
  88 #ifdef USE_CURL_MULTI
  89 static void process_curl_messages(void)
  90 {
  91         int num_messages;
  92         struct active_request_slot *slot;
  93         CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
  94
  95         while (curl_message != NULL) {
  96                 if (curl_message->msg == CURLMSG_DONE) {
  97                         int curl_result = curl_message->data.result;
  98                         slot = active_queue_head;
  99                         while (slot != NULL &&
 100                                slot->curl != curl_message->easy_handle)
 101                                 slot = slot->next;
 102                         if (slot != NULL) {
 103                                 curl_multi_remove_handle(curlm, slot->curl);
 104                                 slot->curl_result = curl_result;
 105                                 finish_active_slot(slot);
 106                         } else {
 107                                 fprintf(stderr, "Received DONE message for unknown request!\n");
 108                         }
 109                 } else {
 110                         fprintf(stderr, "Unknown CURL message received: %d\n",
 111                                 (int)curl_message->msg);
 112                 }
 113                 curl_message = curl_multi_info_read(curlm, &num_messages);
 114         }
 115 }
 116 #endif
 117
 118 static int http_options(const char *var, const char *value, void *cb)
 119 {
 120         if (!strcmp("http.sslverify", var)) {
 121                 curl_ssl_verify = git_config_bool(var, value);
 122                 return 0;
 123         }
 124         if (!strcmp("http.sslcert", var))
 125                 return git_config_string(&ssl_cert, var, value);
 126 #if LIBCURL_VERSION_NUM >= 0x070902
 127         if (!strcmp("http.sslkey", var))
 128                 return git_config_string(&ssl_key, var, value);
 129 #endif
 130 #if LIBCURL_VERSION_NUM >= 0x070908
 131         if (!strcmp("http.sslcapath", var))
 132                 return git_config_string(&ssl_capath, var, value);
 133 #endif
 134         if (!strcmp("http.sslcainfo", var))
 135                 return git_config_string(&ssl_cainfo, var, value);
 136 #ifdef USE_CURL_MULTI
 137         if (!strcmp("http.maxrequests", var)) {
 138                 max_requests = git_config_int(var, value);
 139                 return 0;
 140         }
 141 #endif
 142         if (!strcmp("http.lowspeedlimit", var)) {
 143                 curl_low_speed_limit = (long)git_config_int(var, value);
 144                 return 0;
 145         }
 146         if (!strcmp("http.lowspeedtime", var)) {
 147                 curl_low_speed_time = (long)git_config_int(var, value);
 148                 return 0;
 149         }
 150
 151         if (!strcmp("http.noepsv", var)) {
 152                 curl_ftp_no_epsv = git_config_bool(var, value);
 153                 return 0;
 154         }
 155         if (!strcmp("http.proxy", var))
 156                 return git_config_string(&curl_http_proxy, var, value);
 157
 158         /* Fall back on the default ones */
 159         return git_default_config(var, value, cb);
 160 }
 161
 162 static void init_curl_http_auth(CURL *result)
 163 {
 164         if (user_name) {
 165                 struct strbuf up = STRBUF_INIT;
 166                 if (!user_pass)
 167                         user_pass = xstrdup(getpass("Password: "));
 168                 strbuf_addf(&up, "%s:%s", user_name, user_pass);
 169                 curl_easy_setopt(result, CURLOPT_USERPWD,
 170                                  strbuf_detach(&up, NULL));
 171         }
 172 }
 173
 174 static CURL *get_curl_handle(void)
 175 {
 176         CURL *result = curl_easy_init();
 177
 178         if (!curl_ssl_verify) {
 179                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
 180                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
 181         } else {
 182                 /* Verify authenticity of the peer's certificate */
 183                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
 184                 /* The name in the cert must match whom we tried to connect */
 185                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
 186         }
 187
 188 #if LIBCURL_VERSION_NUM >= 0x070907
 189         curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
 190 #endif
 191
 192         init_curl_http_auth(result);
 193
 194         if (ssl_cert != NULL)
 195                 curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
 196 #if LIBCURL_VERSION_NUM >= 0x070902
 197         if (ssl_key != NULL)
 198                 curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
 199 #endif
 200 #if LIBCURL_VERSION_NUM >= 0x070908
 201         if (ssl_capath != NULL)
 202                 curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
 203 #endif
 204         if (ssl_cainfo != NULL)
 205                 curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
 206         curl_easy_setopt(result, CURLOPT_FAILONERROR, 1);
 207
 208         if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
 209                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
 210                                  curl_low_speed_limit);
 211                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
 212                                  curl_low_speed_time);
 213         }
 214
 215         curl_easy_setopt(result, CURLOPT_FOLLOWLOCATION, 1);
 216
 217         if (getenv("GIT_CURL_VERBOSE"))
 218                 curl_easy_setopt(result, CURLOPT_VERBOSE, 1);
 219
 220         curl_easy_setopt(result, CURLOPT_USERAGENT, GIT_USER_AGENT);
 221
 222         if (curl_ftp_no_epsv)
 223                 curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
 224
 225         if (curl_http_proxy)
 226                 curl_easy_setopt(result, CURLOPT_PROXY, curl_http_proxy);
 227
 228         return result;
 229 }
 230
 231 static void http_auth_init(const char *url)
 232 {
 233         char *at, *colon, *cp, *slash;
 234         int len;
 235
 236         cp = strstr(url, "://");
 237         if (!cp)
 238                 return;
 239
 240         /*
 241          * Ok, the URL looks like "proto://something".  Which one?
 242          * "proto://<user>:<pass>@<host>/...",
 243          * "proto://<user>@<host>/...", or just
 244          * "proto://<host>/..."?
 245          */
 246         cp += 3;
 247         at = strchr(cp, '@');
 248         colon = strchr(cp, ':');
 249         slash = strchrnul(cp, '/');
 250         if (!at || slash <= at)
 251                 return; /* No credentials */
 252         if (!colon || at <= colon) {
 253                 /* Only username */
 254                 len = at - cp;
 255                 user_name = xmalloc(len + 1);
 256                 memcpy(user_name, cp, len);
 257                 user_name[len] = '\0';
 258                 user_pass = NULL;
 259         } else {
 260                 len = colon - cp;
 261                 user_name = xmalloc(len + 1);
 262                 memcpy(user_name, cp, len);
 263                 user_name[len] = '\0';
 264                 len = at - (colon + 1);
 265                 user_pass = xmalloc(len + 1);
 266                 memcpy(user_pass, colon + 1, len);
 267                 user_pass[len] = '\0';
 268         }
 269 }
 270
 271 static void set_from_env(const char **var, const char *envname)
 272 {
 273         const char *val = getenv(envname);
 274         if (val)
 275                 *var = val;
 276 }
 277
 278 void http_init(struct remote *remote)
 279 {
 280         char *low_speed_limit;
 281         char *low_speed_time;
 282
 283         http_is_verbose = 0;
 284
 285         git_config(http_options, NULL);
 286
 287         curl_global_init(CURL_GLOBAL_ALL);
 288
 289         if (remote && remote->http_proxy)
 290                 curl_http_proxy = xstrdup(remote->http_proxy);
 291
 292         pragma_header = curl_slist_append(pragma_header, "Pragma: no-cache");
 293         no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
 294
 295 #ifdef USE_CURL_MULTI
 296         {
 297                 char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
 298                 if (http_max_requests != NULL)
 299                         max_requests = atoi(http_max_requests);
 300         }
 301
 302         curlm = curl_multi_init();
 303         if (curlm == NULL) {
 304                 fprintf(stderr, "Error creating curl multi handle.\n");
 305                 exit(1);
 306         }
 307 #endif
 308
 309         if (getenv("GIT_SSL_NO_VERIFY"))
 310                 curl_ssl_verify = 0;
 311
 312         set_from_env(&ssl_cert, "GIT_SSL_CERT");
 313 #if LIBCURL_VERSION_NUM >= 0x070902
 314         set_from_env(&ssl_key, "GIT_SSL_KEY");
 315 #endif
 316 #if LIBCURL_VERSION_NUM >= 0x070908
 317         set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
 318 #endif
 319         set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
 320
 321         low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
 322         if (low_speed_limit != NULL)
 323                 curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
 324         low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
 325         if (low_speed_time != NULL)
 326                 curl_low_speed_time = strtol(low_speed_time, NULL, 10);
 327
 328         if (curl_ssl_verify == -1)
 329                 curl_ssl_verify = 1;
 330
 331 #ifdef USE_CURL_MULTI
 332         if (max_requests < 1)
 333                 max_requests = DEFAULT_MAX_REQUESTS;
 334 #endif
 335
 336         if (getenv("GIT_CURL_FTP_NO_EPSV"))
 337                 curl_ftp_no_epsv = 1;
 338
 339         if (remote && remote->url && remote->url[0])
 340                 http_auth_init(remote->url[0]);
 341
 342 #ifndef NO_CURL_EASY_DUPHANDLE
 343         curl_default = get_curl_handle();
 344 #endif
 345 }
 346
 347 void http_cleanup(void)
 348 {
 349         struct active_request_slot *slot = active_queue_head;
 350
 351         while (slot != NULL) {
 352                 struct active_request_slot *next = slot->next;
 353                 if (slot->curl != NULL) {
 354 #ifdef USE_CURL_MULTI
 355                         curl_multi_remove_handle(curlm, slot->curl);
 356 #endif
 357                         curl_easy_cleanup(slot->curl);
 358                 }
 359                 free(slot);
 360                 slot = next;
 361         }
 362         active_queue_head = NULL;
 363
 364 #ifndef NO_CURL_EASY_DUPHANDLE
 365         curl_easy_cleanup(curl_default);
 366 #endif
 367
 368 #ifdef USE_CURL_MULTI
 369         curl_multi_cleanup(curlm);
 370 #endif
 371         curl_global_cleanup();
 372
 373         curl_slist_free_all(pragma_header);
 374         pragma_header = NULL;
 375
 376         curl_slist_free_all(no_pragma_header);
 377         no_pragma_header = NULL;
 378
 379         if (curl_http_proxy) {
 380                 free((void *)curl_http_proxy);
 381                 curl_http_proxy = NULL;
 382         }
 383 }
 384
 385 struct active_request_slot *get_active_slot(void)
 386 {
 387         struct active_request_slot *slot = active_queue_head;
 388         struct active_request_slot *newslot;
 389
 390 #ifdef USE_CURL_MULTI
 391         int num_transfers;
 392
 393         /* Wait for a slot to open up if the queue is full */
 394         while (active_requests >= max_requests) {
 395                 curl_multi_perform(curlm, &num_transfers);
 396                 if (num_transfers < active_requests)
 397                         process_curl_messages();
 398         }
 399 #endif
 400
 401         while (slot != NULL && slot->in_use)
 402                 slot = slot->next;
 403
 404         if (slot == NULL) {
 405                 newslot = xmalloc(sizeof(*newslot));
 406                 newslot->curl = NULL;
 407                 newslot->in_use = 0;
 408                 newslot->next = NULL;
 409
 410                 slot = active_queue_head;
 411                 if (slot == NULL) {
 412                         active_queue_head = newslot;
 413                 } else {
 414                         while (slot->next != NULL)
 415                                 slot = slot->next;
 416                         slot->next = newslot;
 417                 }
 418                 slot = newslot;
 419         }
 420
 421         if (slot->curl == NULL) {
 422 #ifdef NO_CURL_EASY_DUPHANDLE
 423                 slot->curl = get_curl_handle();
 424 #else
 425                 slot->curl = curl_easy_duphandle(curl_default);
 426 #endif
 427         }
 428
 429         active_requests++;
 430         slot->in_use = 1;
 431         slot->local = NULL;
 432         slot->results = NULL;
 433         slot->finished = NULL;
 434         slot->callback_data = NULL;
 435         slot->callback_func = NULL;
 436         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
 437         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
 438         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
 439         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
 440         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
 441         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
 442         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 443
 444         return slot;
 445 }
 446
 447 int start_active_slot(struct active_request_slot *slot)
 448 {
 449 #ifdef USE_CURL_MULTI
 450         CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
 451         int num_transfers;
 452
 453         if (curlm_result != CURLM_OK &&
 454             curlm_result != CURLM_CALL_MULTI_PERFORM) {
 455                 active_requests--;
 456                 slot->in_use = 0;
 457                 return 0;
 458         }
 459
 460         /*
 461          * We know there must be something to do, since we just added
 462          * something.
 463          */
 464         curl_multi_perform(curlm, &num_transfers);
 465 #endif
 466         return 1;
 467 }
 468
 469 #ifdef USE_CURL_MULTI
 470 struct fill_chain {
 471         void *data;
 472         int (*fill)(void *);
 473         struct fill_chain *next;
 474 };
 475
 476 static struct fill_chain *fill_cfg;
 477
 478 void add_fill_function(void *data, int (*fill)(void *))
 479 {
 480         struct fill_chain *new = xmalloc(sizeof(*new));
 481         struct fill_chain **linkp = &fill_cfg;
 482         new->data = data;
 483         new->fill = fill;
 484         new->next = NULL;
 485         while (*linkp)
 486                 linkp = &(*linkp)->next;
 487         *linkp = new;
 488 }
 489
 490 void fill_active_slots(void)
 491 {
 492         struct active_request_slot *slot = active_queue_head;
 493
 494         while (active_requests < max_requests) {
 495                 struct fill_chain *fill;
 496                 for (fill = fill_cfg; fill; fill = fill->next)
 497                         if (fill->fill(fill->data))
 498                                 break;
 499
 500                 if (!fill)
 501                         break;
 502         }
 503
 504         while (slot != NULL) {
 505                 if (!slot->in_use && slot->curl != NULL) {
 506                         curl_easy_cleanup(slot->curl);
 507                         slot->curl = NULL;
 508                 }
 509                 slot = slot->next;
 510         }
 511 }
 512
 513 void step_active_slots(void)
 514 {
 515         int num_transfers;
 516         CURLMcode curlm_result;
 517
 518         do {
 519                 curlm_result = curl_multi_perform(curlm, &num_transfers);
 520         } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
 521         if (num_transfers < active_requests) {
 522                 process_curl_messages();
 523                 fill_active_slots();
 524         }
 525 }
 526 #endif
 527
 528 void run_active_slot(struct active_request_slot *slot)
 529 {
 530 #ifdef USE_CURL_MULTI
 531         long last_pos = 0;
 532         long current_pos;
 533         fd_set readfds;
 534         fd_set writefds;
 535         fd_set excfds;
 536         int max_fd;
 537         struct timeval select_timeout;
 538         int finished = 0;
 539
 540         slot->finished = &finished;
 541         while (!finished) {
 542                 data_received = 0;
 543                 step_active_slots();
 544
 545                 if (!data_received && slot->local != NULL) {
 546                         current_pos = ftell(slot->local);
 547                         if (current_pos > last_pos)
 548                                 data_received++;
 549                         last_pos = current_pos;
 550                 }
 551
 552                 if (slot->in_use && !data_received) {
 553                         max_fd = 0;
 554                         FD_ZERO(&readfds);
 555                         FD_ZERO(&writefds);
 556                         FD_ZERO(&excfds);
 557                         select_timeout.tv_sec = 0;
 558                         select_timeout.tv_usec = 50000;
 559                         select(max_fd, &readfds, &writefds,
 560                                &excfds, &select_timeout);
 561                 }
 562         }
 563 #else
 564         while (slot->in_use) {
 565                 slot->curl_result = curl_easy_perform(slot->curl);
 566                 finish_active_slot(slot);
 567         }
 568 #endif
 569 }
 570
 571 static void closedown_active_slot(struct active_request_slot *slot)
 572 {
 573         active_requests--;
 574         slot->in_use = 0;
 575 }
 576
 577 void release_active_slot(struct active_request_slot *slot)
 578 {
 579         closedown_active_slot(slot);
 580         if (slot->curl) {
 581 #ifdef USE_CURL_MULTI
 582                 curl_multi_remove_handle(curlm, slot->curl);
 583 #endif
 584                 curl_easy_cleanup(slot->curl);
 585                 slot->curl = NULL;
 586         }
 587 #ifdef USE_CURL_MULTI
 588         fill_active_slots();
 589 #endif
 590 }
 591
 592 static void finish_active_slot(struct active_request_slot *slot)
 593 {
 594         closedown_active_slot(slot);
 595         curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
 596
 597         if (slot->finished != NULL)
 598                 (*slot->finished) = 1;
 599
 600         /* Store slot results so they can be read after the slot is reused */
 601         if (slot->results != NULL) {
 602                 slot->results->curl_result = slot->curl_result;
 603                 slot->results->http_code = slot->http_code;
 604         }
 605
 606         /* Run callback if appropriate */
 607         if (slot->callback_func != NULL)
 608                 slot->callback_func(slot->callback_data);
 609 }
 610
 611 void finish_all_active_slots(void)
 612 {
 613         struct active_request_slot *slot = active_queue_head;
 614
 615         while (slot != NULL)
 616                 if (slot->in_use) {
 617                         run_active_slot(slot);
 618                         slot = active_queue_head;
 619                 } else {
 620                         slot = slot->next;
 621                 }
 622 }
 623
 624 /* Helpers for modifying and creating URLs */
 625 static inline int needs_quote(int ch)
 626 {
 627         if (((ch >= 'A') && (ch <= 'Z'))
 628                         || ((ch >= 'a') && (ch <= 'z'))
 629                         || ((ch >= '0') && (ch <= '9'))
 630                         || (ch == '/')
 631                         || (ch == '-')
 632                         || (ch == '.'))
 633                 return 0;
 634         return 1;
 635 }
 636
 637 static inline int hex(int v)
 638 {
 639         if (v < 10)
 640                 return '0' + v;
 641         else
 642                 return 'A' + v - 10;
 643 }
 644
 645 static void end_url_with_slash(struct strbuf *buf, const char *url)
 646 {
 647         strbuf_addstr(buf, url);
 648         if (buf->len && buf->buf[buf->len - 1] != '/')
 649                 strbuf_addstr(buf, "/");
 650 }
 651
 652 static char *quote_ref_url(const char *base, const char *ref)
 653 {
 654         struct strbuf buf = STRBUF_INIT;
 655         const char *cp;
 656         int ch;
 657
 658         end_url_with_slash(&buf, base);
 659
 660         for (cp = ref; (ch = *cp) != 0; cp++)
 661                 if (needs_quote(ch))
 662                         strbuf_addf(&buf, "%%%02x", ch);
 663                 else
 664                         strbuf_addch(&buf, *cp);
 665
 666         return strbuf_detach(&buf, NULL);
 667 }
 668
 669 /* http_request() targets */
 670 #define HTTP_REQUEST_STRBUF     0
 671 #define HTTP_REQUEST_FILE       1
 672
 673 static int http_request(const char *url, void *result, int target, int options)
 674 {
 675         struct active_request_slot *slot;
 676         struct slot_results results;
 677         struct curl_slist *headers = NULL;
 678         struct strbuf buf = STRBUF_INIT;
 679         int ret;
 680
 681         slot = get_active_slot();
 682         slot->results = &results;
 683         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 684
 685         if (result == NULL) {
 686                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
 687         } else {
 688                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
 689                 curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
 690
 691                 if (target == HTTP_REQUEST_FILE) {
 692                         long posn = ftell(result);
 693                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
 694                                          fwrite);
 695                         if (posn > 0) {
 696                                 strbuf_addf(&buf, "Range: bytes=%ld-", posn);
 697                                 headers = curl_slist_append(headers, buf.buf);
 698                                 strbuf_reset(&buf);
 699                         }
 700                         slot->local = result;
 701                 } else
 702                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
 703                                          fwrite_buffer);
 704         }
 705
 706         strbuf_addstr(&buf, "Pragma:");
 707         if (options & HTTP_NO_CACHE)
 708                 strbuf_addstr(&buf, " no-cache");
 709
 710         headers = curl_slist_append(headers, buf.buf);
 711
 712         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
 713         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
 714
 715         if (start_active_slot(slot)) {
 716                 run_active_slot(slot);
 717                 if (results.curl_result == CURLE_OK)
 718                         ret = HTTP_OK;
 719                 else if (missing_target(&results))
 720                         ret = HTTP_MISSING_TARGET;
 721                 else
 722                         ret = HTTP_ERROR;
 723         } else {
 724                 error("Unable to start HTTP request for %s", url);
 725                 ret = HTTP_START_FAILED;
 726         }
 727
 728         slot->local = NULL;
 729         curl_slist_free_all(headers);
 730         strbuf_release(&buf);
 731
 732         return ret;
 733 }
 734
 735 int http_get_strbuf(const char *url, struct strbuf *result, int options)
 736 {
 737         return http_request(url, result, HTTP_REQUEST_STRBUF, options);
 738 }
 739
 740 int http_get_file(const char *url, const char *filename, int options)
 741 {
 742         int ret;
 743         struct strbuf tmpfile = STRBUF_INIT;
 744         FILE *result;
 745
 746         strbuf_addf(&tmpfile, "%s.temp", filename);
 747         result = fopen(tmpfile.buf, "a");
 748         if (! result) {
 749                 error("Unable to open local file %s", tmpfile.buf);
 750                 ret = HTTP_ERROR;
 751                 goto cleanup;
 752         }
 753
 754         ret = http_request(url, result, HTTP_REQUEST_FILE, options);
 755         fclose(result);
 756
 757         if ((ret == HTTP_OK) && move_temp_to_file(tmpfile.buf, filename))
 758                 ret = HTTP_ERROR;
 759 cleanup:
 760         strbuf_release(&tmpfile);
 761         return ret;
 762 }
 763
 764 int http_error(const char *url, int ret)
 765 {
 766         /* http_request has already handled HTTP_START_FAILED. */
 767         if (ret != HTTP_START_FAILED)
 768                 error("%s while accessing %s\n", curl_errorstr, url);
 769
 770         return ret;
 771 }
 772
 773 int http_fetch_ref(const char *base, struct ref *ref)
 774 {
 775         char *url;
 776         struct strbuf buffer = STRBUF_INIT;
 777         int ret = -1;
 778
 779         url = quote_ref_url(base, ref->name);
 780         if (http_get_strbuf(url, &buffer, HTTP_NO_CACHE) == HTTP_OK) {
 781                 strbuf_rtrim(&buffer);
 782                 if (buffer.len == 40)
 783                         ret = get_sha1_hex(buffer.buf, ref->old_sha1);
 784                 else if (!prefixcmp(buffer.buf, "ref: ")) {
 785                         ref->symref = xstrdup(buffer.buf + 5);
 786                         ret = 0;
 787                 }
 788         }
 789
 790         strbuf_release(&buffer);
 791         free(url);
 792         return ret;
 793 }
 794
 795 /* Helpers for fetching packs */
 796 static int fetch_pack_index(unsigned char *sha1, const char *base_url)
 797 {
 798         int ret = 0;
 799         char *hex = xstrdup(sha1_to_hex(sha1));
 800         char *filename;
 801         char *url;
 802         struct strbuf buf = STRBUF_INIT;
 803
 804         /* Don't use the index if the pack isn't there */
 805         end_url_with_slash(&buf, base_url);
 806         strbuf_addf(&buf, "objects/pack/pack-%s.pack", hex);
 807         url = strbuf_detach(&buf, 0);
 808
 809         if (http_get_strbuf(url, NULL, 0)) {
 810                 ret = error("Unable to verify pack %s is available",
 811                             hex);
 812                 goto cleanup;
 813         }
 814
 815         if (has_pack_index(sha1)) {
 816                 ret = 0;
 817                 goto cleanup;
 818         }
 819
 820         if (http_is_verbose)
 821                 fprintf(stderr, "Getting index for pack %s\n", hex);
 822
 823         end_url_with_slash(&buf, base_url);
 824         strbuf_addf(&buf, "objects/pack/pack-%s.idx", hex);
 825         url = strbuf_detach(&buf, NULL);
 826
 827         filename = sha1_pack_index_name(sha1);
 828         if (http_get_file(url, filename, 0) != HTTP_OK)
 829                 ret = error("Unable to get pack index %s\n", url);
 830
 831 cleanup:
 832         free(hex);
 833         free(url);
 834         return ret;
 835 }
 836
 837 static int fetch_and_setup_pack_index(struct packed_git **packs_head,
 838         unsigned char *sha1, const char *base_url)
 839 {
 840         struct packed_git *new_pack;
 841
 842         if (fetch_pack_index(sha1, base_url))
 843                 return -1;
 844
 845         new_pack = parse_pack_index(sha1);
 846         if (!new_pack)
 847                 return -1; /* parse_pack_index() already issued error message */
 848         new_pack->next = *packs_head;
 849         *packs_head = new_pack;
 850         return 0;
 851 }
 852
 853 int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
 854 {
 855         int ret = 0, i = 0;
 856         char *url, *data;
 857         struct strbuf buf = STRBUF_INIT;
 858         unsigned char sha1[20];
 859
 860         end_url_with_slash(&buf, base_url);
 861         strbuf_addstr(&buf, "objects/info/packs");
 862         url = strbuf_detach(&buf, NULL);
 863
 864         ret = http_get_strbuf(url, &buf, HTTP_NO_CACHE);
 865         if (ret != HTTP_OK)
 866                 goto cleanup;
 867
 868         data = buf.buf;
 869         while (i < buf.len) {
 870                 switch (data[i]) {
 871                 case 'P':
 872                         i++;
 873                         if (i + 52 <= buf.len &&
 874                             !prefixcmp(data + i, " pack-") &&
 875                             !prefixcmp(data + i + 46, ".pack\n")) {
 876                                 get_sha1_hex(data + i + 6, sha1);
 877                                 fetch_and_setup_pack_index(packs_head, sha1,
 878                                                       base_url);
 879                                 i += 51;
 880                                 break;
 881                         }
 882                 default:
 883                         while (i < buf.len && data[i] != '\n')
 884                                 i++;
 885                 }
 886                 i++;
 887         }
 888
 889 cleanup:
 890         free(url);
 891         return ret;
 892 }
 893
 894 void release_http_pack_request(struct http_pack_request *preq)
 895 {
 896         if (preq->packfile != NULL) {
 897                 fclose(preq->packfile);
 898                 preq->packfile = NULL;
 899                 preq->slot->local = NULL;
 900         }
 901         if (preq->range_header != NULL) {
 902                 curl_slist_free_all(preq->range_header);
 903                 preq->range_header = NULL;
 904         }
 905         preq->slot = NULL;
 906         free(preq->url);
 907 }
 908
 909 int finish_http_pack_request(struct http_pack_request *preq)
 910 {
 911         int ret;
 912         struct packed_git **lst;
 913
 914         preq->target->pack_size = ftell(preq->packfile);
 915
 916         if (preq->packfile != NULL) {
 917                 fclose(preq->packfile);
 918                 preq->packfile = NULL;
 919                 preq->slot->local = NULL;
 920         }
 921
 922         ret = move_temp_to_file(preq->tmpfile, preq->filename);
 923         if (ret)
 924                 return ret;
 925
 926         lst = preq->lst;
 927         while (*lst != preq->target)
 928                 lst = &((*lst)->next);
 929         *lst = (*lst)->next;
 930
 931         if (verify_pack(preq->target))
 932                 return -1;
 933         install_packed_git(preq->target);
 934
 935         return 0;
 936 }
 937
 938 struct http_pack_request *new_http_pack_request(
 939         struct packed_git *target, const char *base_url)
 940 {
 941         char *url;
 942         char *filename;
 943         long prev_posn = 0;
 944         char range[RANGE_HEADER_SIZE];
 945         struct strbuf buf = STRBUF_INIT;
 946         struct http_pack_request *preq;
 947
 948         preq = xmalloc(sizeof(*preq));
 949         preq->target = target;
 950         preq->range_header = NULL;
 951
 952         end_url_with_slash(&buf, base_url);
 953         strbuf_addf(&buf, "objects/pack/pack-%s.pack",
 954                 sha1_to_hex(target->sha1));
 955         url = strbuf_detach(&buf, NULL);
 956         preq->url = xstrdup(url);
 957
 958         filename = sha1_pack_name(target->sha1);
 959         snprintf(preq->filename, sizeof(preq->filename), "%s", filename);
 960         snprintf(preq->tmpfile, sizeof(preq->tmpfile), "%s.temp", filename);
 961         preq->packfile = fopen(preq->tmpfile, "a");
 962         if (!preq->packfile) {
 963                 error("Unable to open local file %s for pack",
 964                       preq->tmpfile);
 965                 goto abort;
 966         }
 967
 968         preq->slot = get_active_slot();
 969         preq->slot->local = preq->packfile;
 970         curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
 971         curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
 972         curl_easy_setopt(preq->slot->curl, CURLOPT_URL, url);
 973         curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
 974                 no_pragma_header);
 975
 976         /*
 977          * If there is data present from a previous transfer attempt,
 978          * resume where it left off
 979          */
 980         prev_posn = ftell(preq->packfile);
 981         if (prev_posn>0) {
 982                 if (http_is_verbose)
 983                         fprintf(stderr,
 984                                 "Resuming fetch of pack %s at byte %ld\n",
 985                                 sha1_to_hex(target->sha1), prev_posn);
 986                 sprintf(range, "Range: bytes=%ld-", prev_posn);
 987                 preq->range_header = curl_slist_append(NULL, range);
 988                 curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
 989                         preq->range_header);
 990         }
 991
 992         return preq;
 993
 994 abort:
 995         free(filename);
 996         return NULL;
 997 }