git.oblomov.eu Git - git/blob - http.c

   1 #include "http.h"
   2 #include "pack.h"
   3 #include "sideband.h"
   4 #include "run-command.h"
   5 #include "url.h"
   6 #include "credential.h"
   7 #include "version.h"
   8 #include "pkt-line.h"
   9
  10 int active_requests;
  11 int http_is_verbose;
  12 size_t http_post_buffer = 16 * LARGE_PACKET_MAX;
  13
  14 #if LIBCURL_VERSION_NUM >= 0x070a06
  15 #define LIBCURL_CAN_HANDLE_AUTH_ANY
  16 #endif
  17
  18 static int min_curl_sessions = 1;
  19 static int curl_session_count;
  20 #ifdef USE_CURL_MULTI
  21 static int max_requests = -1;
  22 static CURLM *curlm;
  23 #endif
  24 #ifndef NO_CURL_EASY_DUPHANDLE
  25 static CURL *curl_default;
  26 #endif
  27
  28 #define PREV_BUF_SIZE 4096
  29 #define RANGE_HEADER_SIZE 30
  30
  31 char curl_errorstr[CURL_ERROR_SIZE];
  32
  33 static int curl_ssl_verify = -1;
  34 static int curl_ssl_try;
  35 static const char *ssl_cert;
  36 #if LIBCURL_VERSION_NUM >= 0x070903
  37 static const char *ssl_key;
  38 #endif
  39 #if LIBCURL_VERSION_NUM >= 0x070908
  40 static const char *ssl_capath;
  41 #endif
  42 static const char *ssl_cainfo;
  43 static long curl_low_speed_limit = -1;
  44 static long curl_low_speed_time = -1;
  45 static int curl_ftp_no_epsv;
  46 static const char *curl_http_proxy;
  47 static const char *curl_cookie_file;
  48 static struct credential http_auth = CREDENTIAL_INIT;
  49 static int http_proactive_auth;
  50 static const char *user_agent;
  51
  52 #if LIBCURL_VERSION_NUM >= 0x071700
  53 /* Use CURLOPT_KEYPASSWD as is */
  54 #elif LIBCURL_VERSION_NUM >= 0x070903
  55 #define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
  56 #else
  57 #define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
  58 #endif
  59
  60 static struct credential cert_auth = CREDENTIAL_INIT;
  61 static int ssl_cert_password_required;
  62
  63 static struct curl_slist *pragma_header;
  64 static struct curl_slist *no_pragma_header;
  65
  66 static struct active_request_slot *active_queue_head;
  67
  68 size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
  69 {
  70         size_t size = eltsize * nmemb;
  71         struct buffer *buffer = buffer_;
  72
  73         if (size > buffer->buf.len - buffer->posn)
  74                 size = buffer->buf.len - buffer->posn;
  75         memcpy(ptr, buffer->buf.buf + buffer->posn, size);
  76         buffer->posn += size;
  77
  78         return size;
  79 }
  80
  81 #ifndef NO_CURL_IOCTL
  82 curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
  83 {
  84         struct buffer *buffer = clientp;
  85
  86         switch (cmd) {
  87         case CURLIOCMD_NOP:
  88                 return CURLIOE_OK;
  89
  90         case CURLIOCMD_RESTARTREAD:
  91                 buffer->posn = 0;
  92                 return CURLIOE_OK;
  93
  94         default:
  95                 return CURLIOE_UNKNOWNCMD;
  96         }
  97 }
  98 #endif
  99
 100 size_t fwrite_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
 101 {
 102         size_t size = eltsize * nmemb;
 103         struct strbuf *buffer = buffer_;
 104
 105         strbuf_add(buffer, ptr, size);
 106         return size;
 107 }
 108
 109 size_t fwrite_null(char *ptr, size_t eltsize, size_t nmemb, void *strbuf)
 110 {
 111         return eltsize * nmemb;
 112 }
 113
 114 #ifdef USE_CURL_MULTI
 115 static void process_curl_messages(void)
 116 {
 117         int num_messages;
 118         struct active_request_slot *slot;
 119         CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
 120
 121         while (curl_message != NULL) {
 122                 if (curl_message->msg == CURLMSG_DONE) {
 123                         int curl_result = curl_message->data.result;
 124                         slot = active_queue_head;
 125                         while (slot != NULL &&
 126                                slot->curl != curl_message->easy_handle)
 127                                 slot = slot->next;
 128                         if (slot != NULL) {
 129                                 curl_multi_remove_handle(curlm, slot->curl);
 130                                 slot->curl_result = curl_result;
 131                                 finish_active_slot(slot);
 132                         } else {
 133                                 fprintf(stderr, "Received DONE message for unknown request!\n");
 134                         }
 135                 } else {
 136                         fprintf(stderr, "Unknown CURL message received: %d\n",
 137                                 (int)curl_message->msg);
 138                 }
 139                 curl_message = curl_multi_info_read(curlm, &num_messages);
 140         }
 141 }
 142 #endif
 143
 144 static int http_options(const char *var, const char *value, void *cb)
 145 {
 146         if (!strcmp("http.sslverify", var)) {
 147                 curl_ssl_verify = git_config_bool(var, value);
 148                 return 0;
 149         }
 150         if (!strcmp("http.sslcert", var))
 151                 return git_config_string(&ssl_cert, var, value);
 152 #if LIBCURL_VERSION_NUM >= 0x070903
 153         if (!strcmp("http.sslkey", var))
 154                 return git_config_string(&ssl_key, var, value);
 155 #endif
 156 #if LIBCURL_VERSION_NUM >= 0x070908
 157         if (!strcmp("http.sslcapath", var))
 158                 return git_config_string(&ssl_capath, var, value);
 159 #endif
 160         if (!strcmp("http.sslcainfo", var))
 161                 return git_config_string(&ssl_cainfo, var, value);
 162         if (!strcmp("http.sslcertpasswordprotected", var)) {
 163                 if (git_config_bool(var, value))
 164                         ssl_cert_password_required = 1;
 165                 return 0;
 166         }
 167         if (!strcmp("http.ssltry", var)) {
 168                 curl_ssl_try = git_config_bool(var, value);
 169                 return 0;
 170         }
 171         if (!strcmp("http.minsessions", var)) {
 172                 min_curl_sessions = git_config_int(var, value);
 173 #ifndef USE_CURL_MULTI
 174                 if (min_curl_sessions > 1)
 175                         min_curl_sessions = 1;
 176 #endif
 177                 return 0;
 178         }
 179 #ifdef USE_CURL_MULTI
 180         if (!strcmp("http.maxrequests", var)) {
 181                 max_requests = git_config_int(var, value);
 182                 return 0;
 183         }
 184 #endif
 185         if (!strcmp("http.lowspeedlimit", var)) {
 186                 curl_low_speed_limit = (long)git_config_int(var, value);
 187                 return 0;
 188         }
 189         if (!strcmp("http.lowspeedtime", var)) {
 190                 curl_low_speed_time = (long)git_config_int(var, value);
 191                 return 0;
 192         }
 193
 194         if (!strcmp("http.noepsv", var)) {
 195                 curl_ftp_no_epsv = git_config_bool(var, value);
 196                 return 0;
 197         }
 198         if (!strcmp("http.proxy", var))
 199                 return git_config_string(&curl_http_proxy, var, value);
 200
 201         if (!strcmp("http.cookiefile", var))
 202                 return git_config_string(&curl_cookie_file, var, value);
 203
 204         if (!strcmp("http.postbuffer", var)) {
 205                 http_post_buffer = git_config_int(var, value);
 206                 if (http_post_buffer < LARGE_PACKET_MAX)
 207                         http_post_buffer = LARGE_PACKET_MAX;
 208                 return 0;
 209         }
 210
 211         if (!strcmp("http.useragent", var))
 212                 return git_config_string(&user_agent, var, value);
 213
 214         /* Fall back on the default ones */
 215         return git_default_config(var, value, cb);
 216 }
 217
 218 static void init_curl_http_auth(CURL *result)
 219 {
 220         if (!http_auth.username)
 221                 return;
 222
 223         credential_fill(&http_auth);
 224
 225 #if LIBCURL_VERSION_NUM >= 0x071301
 226         curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username);
 227         curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password);
 228 #else
 229         {
 230                 static struct strbuf up = STRBUF_INIT;
 231                 strbuf_reset(&up);
 232                 strbuf_addf(&up, "%s:%s",
 233                             http_auth.username, http_auth.password);
 234                 curl_easy_setopt(result, CURLOPT_USERPWD, up.buf);
 235         }
 236 #endif
 237 }
 238
 239 static int has_cert_password(void)
 240 {
 241         if (ssl_cert == NULL || ssl_cert_password_required != 1)
 242                 return 0;
 243         if (!cert_auth.password) {
 244                 cert_auth.protocol = xstrdup("cert");
 245                 cert_auth.username = xstrdup("");
 246                 cert_auth.path = xstrdup(ssl_cert);
 247                 credential_fill(&cert_auth);
 248         }
 249         return 1;
 250 }
 251
 252 static CURL *get_curl_handle(void)
 253 {
 254         CURL *result = curl_easy_init();
 255
 256         if (!curl_ssl_verify) {
 257                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
 258                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
 259         } else {
 260                 /* Verify authenticity of the peer's certificate */
 261                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
 262                 /* The name in the cert must match whom we tried to connect */
 263                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
 264         }
 265
 266 #if LIBCURL_VERSION_NUM >= 0x070907
 267         curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
 268 #endif
 269 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 270         curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 271 #endif
 272
 273         if (http_proactive_auth)
 274                 init_curl_http_auth(result);
 275
 276         if (ssl_cert != NULL)
 277                 curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
 278         if (has_cert_password())
 279                 curl_easy_setopt(result, CURLOPT_KEYPASSWD, cert_auth.password);
 280 #if LIBCURL_VERSION_NUM >= 0x070903
 281         if (ssl_key != NULL)
 282                 curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
 283 #endif
 284 #if LIBCURL_VERSION_NUM >= 0x070908
 285         if (ssl_capath != NULL)
 286                 curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
 287 #endif
 288         if (ssl_cainfo != NULL)
 289                 curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
 290
 291         if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
 292                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
 293                                  curl_low_speed_limit);
 294                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
 295                                  curl_low_speed_time);
 296         }
 297
 298         curl_easy_setopt(result, CURLOPT_FOLLOWLOCATION, 1);
 299 #if LIBCURL_VERSION_NUM >= 0x071301
 300         curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
 301 #elif LIBCURL_VERSION_NUM >= 0x071101
 302         curl_easy_setopt(result, CURLOPT_POST301, 1);
 303 #endif
 304
 305         if (getenv("GIT_CURL_VERBOSE"))
 306                 curl_easy_setopt(result, CURLOPT_VERBOSE, 1);
 307
 308         curl_easy_setopt(result, CURLOPT_USERAGENT,
 309                 user_agent ? user_agent : git_user_agent());
 310
 311         if (curl_ftp_no_epsv)
 312                 curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
 313
 314 #ifdef CURLOPT_USE_SSL
 315         if (curl_ssl_try)
 316                 curl_easy_setopt(result, CURLOPT_USE_SSL, CURLUSESSL_TRY);
 317 #endif
 318
 319         if (curl_http_proxy) {
 320                 curl_easy_setopt(result, CURLOPT_PROXY, curl_http_proxy);
 321                 curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 322         }
 323
 324         return result;
 325 }
 326
 327 static void set_from_env(const char **var, const char *envname)
 328 {
 329         const char *val = getenv(envname);
 330         if (val)
 331                 *var = val;
 332 }
 333
 334 void http_init(struct remote *remote, const char *url, int proactive_auth)
 335 {
 336         char *low_speed_limit;
 337         char *low_speed_time;
 338
 339         http_is_verbose = 0;
 340
 341         git_config(http_options, NULL);
 342
 343         curl_global_init(CURL_GLOBAL_ALL);
 344
 345         http_proactive_auth = proactive_auth;
 346
 347         if (remote && remote->http_proxy)
 348                 curl_http_proxy = xstrdup(remote->http_proxy);
 349
 350         pragma_header = curl_slist_append(pragma_header, "Pragma: no-cache");
 351         no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
 352
 353 #ifdef USE_CURL_MULTI
 354         {
 355                 char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
 356                 if (http_max_requests != NULL)
 357                         max_requests = atoi(http_max_requests);
 358         }
 359
 360         curlm = curl_multi_init();
 361         if (curlm == NULL) {
 362                 fprintf(stderr, "Error creating curl multi handle.\n");
 363                 exit(1);
 364         }
 365 #endif
 366
 367         if (getenv("GIT_SSL_NO_VERIFY"))
 368                 curl_ssl_verify = 0;
 369
 370         set_from_env(&ssl_cert, "GIT_SSL_CERT");
 371 #if LIBCURL_VERSION_NUM >= 0x070903
 372         set_from_env(&ssl_key, "GIT_SSL_KEY");
 373 #endif
 374 #if LIBCURL_VERSION_NUM >= 0x070908
 375         set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
 376 #endif
 377         set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
 378
 379         set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
 380
 381         low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
 382         if (low_speed_limit != NULL)
 383                 curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
 384         low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
 385         if (low_speed_time != NULL)
 386                 curl_low_speed_time = strtol(low_speed_time, NULL, 10);
 387
 388         if (curl_ssl_verify == -1)
 389                 curl_ssl_verify = 1;
 390
 391         curl_session_count = 0;
 392 #ifdef USE_CURL_MULTI
 393         if (max_requests < 1)
 394                 max_requests = DEFAULT_MAX_REQUESTS;
 395 #endif
 396
 397         if (getenv("GIT_CURL_FTP_NO_EPSV"))
 398                 curl_ftp_no_epsv = 1;
 399
 400         if (url) {
 401                 credential_from_url(&http_auth, url);
 402                 if (!ssl_cert_password_required &&
 403                     getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
 404                     !prefixcmp(url, "https://"))
 405                         ssl_cert_password_required = 1;
 406         }
 407
 408 #ifndef NO_CURL_EASY_DUPHANDLE
 409         curl_default = get_curl_handle();
 410 #endif
 411 }
 412
 413 void http_cleanup(void)
 414 {
 415         struct active_request_slot *slot = active_queue_head;
 416
 417         while (slot != NULL) {
 418                 struct active_request_slot *next = slot->next;
 419                 if (slot->curl != NULL) {
 420 #ifdef USE_CURL_MULTI
 421                         curl_multi_remove_handle(curlm, slot->curl);
 422 #endif
 423                         curl_easy_cleanup(slot->curl);
 424                 }
 425                 free(slot);
 426                 slot = next;
 427         }
 428         active_queue_head = NULL;
 429
 430 #ifndef NO_CURL_EASY_DUPHANDLE
 431         curl_easy_cleanup(curl_default);
 432 #endif
 433
 434 #ifdef USE_CURL_MULTI
 435         curl_multi_cleanup(curlm);
 436 #endif
 437         curl_global_cleanup();
 438
 439         curl_slist_free_all(pragma_header);
 440         pragma_header = NULL;
 441
 442         curl_slist_free_all(no_pragma_header);
 443         no_pragma_header = NULL;
 444
 445         if (curl_http_proxy) {
 446                 free((void *)curl_http_proxy);
 447                 curl_http_proxy = NULL;
 448         }
 449
 450         if (cert_auth.password != NULL) {
 451                 memset(cert_auth.password, 0, strlen(cert_auth.password));
 452                 free(cert_auth.password);
 453                 cert_auth.password = NULL;
 454         }
 455         ssl_cert_password_required = 0;
 456 }
 457
 458 struct active_request_slot *get_active_slot(void)
 459 {
 460         struct active_request_slot *slot = active_queue_head;
 461         struct active_request_slot *newslot;
 462
 463 #ifdef USE_CURL_MULTI
 464         int num_transfers;
 465
 466         /* Wait for a slot to open up if the queue is full */
 467         while (active_requests >= max_requests) {
 468                 curl_multi_perform(curlm, &num_transfers);
 469                 if (num_transfers < active_requests)
 470                         process_curl_messages();
 471         }
 472 #endif
 473
 474         while (slot != NULL && slot->in_use)
 475                 slot = slot->next;
 476
 477         if (slot == NULL) {
 478                 newslot = xmalloc(sizeof(*newslot));
 479                 newslot->curl = NULL;
 480                 newslot->in_use = 0;
 481                 newslot->next = NULL;
 482
 483                 slot = active_queue_head;
 484                 if (slot == NULL) {
 485                         active_queue_head = newslot;
 486                 } else {
 487                         while (slot->next != NULL)
 488                                 slot = slot->next;
 489                         slot->next = newslot;
 490                 }
 491                 slot = newslot;
 492         }
 493
 494         if (slot->curl == NULL) {
 495 #ifdef NO_CURL_EASY_DUPHANDLE
 496                 slot->curl = get_curl_handle();
 497 #else
 498                 slot->curl = curl_easy_duphandle(curl_default);
 499 #endif
 500                 curl_session_count++;
 501         }
 502
 503         active_requests++;
 504         slot->in_use = 1;
 505         slot->results = NULL;
 506         slot->finished = NULL;
 507         slot->callback_data = NULL;
 508         slot->callback_func = NULL;
 509         curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
 510         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
 511         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
 512         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
 513         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
 514         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
 515         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
 516         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
 517         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 518         curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 1);
 519         if (http_auth.password)
 520                 init_curl_http_auth(slot->curl);
 521
 522         return slot;
 523 }
 524
 525 int start_active_slot(struct active_request_slot *slot)
 526 {
 527 #ifdef USE_CURL_MULTI
 528         CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
 529         int num_transfers;
 530
 531         if (curlm_result != CURLM_OK &&
 532             curlm_result != CURLM_CALL_MULTI_PERFORM) {
 533                 active_requests--;
 534                 slot->in_use = 0;
 535                 return 0;
 536         }
 537
 538         /*
 539          * We know there must be something to do, since we just added
 540          * something.
 541          */
 542         curl_multi_perform(curlm, &num_transfers);
 543 #endif
 544         return 1;
 545 }
 546
 547 #ifdef USE_CURL_MULTI
 548 struct fill_chain {
 549         void *data;
 550         int (*fill)(void *);
 551         struct fill_chain *next;
 552 };
 553
 554 static struct fill_chain *fill_cfg;
 555
 556 void add_fill_function(void *data, int (*fill)(void *))
 557 {
 558         struct fill_chain *new = xmalloc(sizeof(*new));
 559         struct fill_chain **linkp = &fill_cfg;
 560         new->data = data;
 561         new->fill = fill;
 562         new->next = NULL;
 563         while (*linkp)
 564                 linkp = &(*linkp)->next;
 565         *linkp = new;
 566 }
 567
 568 void fill_active_slots(void)
 569 {
 570         struct active_request_slot *slot = active_queue_head;
 571
 572         while (active_requests < max_requests) {
 573                 struct fill_chain *fill;
 574                 for (fill = fill_cfg; fill; fill = fill->next)
 575                         if (fill->fill(fill->data))
 576                                 break;
 577
 578                 if (!fill)
 579                         break;
 580         }
 581
 582         while (slot != NULL) {
 583                 if (!slot->in_use && slot->curl != NULL
 584                         && curl_session_count > min_curl_sessions) {
 585                         curl_easy_cleanup(slot->curl);
 586                         slot->curl = NULL;
 587                         curl_session_count--;
 588                 }
 589                 slot = slot->next;
 590         }
 591 }
 592
 593 void step_active_slots(void)
 594 {
 595         int num_transfers;
 596         CURLMcode curlm_result;
 597
 598         do {
 599                 curlm_result = curl_multi_perform(curlm, &num_transfers);
 600         } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
 601         if (num_transfers < active_requests) {
 602                 process_curl_messages();
 603                 fill_active_slots();
 604         }
 605 }
 606 #endif
 607
 608 void run_active_slot(struct active_request_slot *slot)
 609 {
 610 #ifdef USE_CURL_MULTI
 611         fd_set readfds;
 612         fd_set writefds;
 613         fd_set excfds;
 614         int max_fd;
 615         struct timeval select_timeout;
 616         int finished = 0;
 617
 618         slot->finished = &finished;
 619         while (!finished) {
 620                 step_active_slots();
 621
 622                 if (slot->in_use) {
 623 #if LIBCURL_VERSION_NUM >= 0x070f04
 624                         long curl_timeout;
 625                         curl_multi_timeout(curlm, &curl_timeout);
 626                         if (curl_timeout == 0) {
 627                                 continue;
 628                         } else if (curl_timeout == -1) {
 629                                 select_timeout.tv_sec  = 0;
 630                                 select_timeout.tv_usec = 50000;
 631                         } else {
 632                                 select_timeout.tv_sec  =  curl_timeout / 1000;
 633                                 select_timeout.tv_usec = (curl_timeout % 1000) * 1000;
 634                         }
 635 #else
 636                         select_timeout.tv_sec  = 0;
 637                         select_timeout.tv_usec = 50000;
 638 #endif
 639
 640                         max_fd = -1;
 641                         FD_ZERO(&readfds);
 642                         FD_ZERO(&writefds);
 643                         FD_ZERO(&excfds);
 644                         curl_multi_fdset(curlm, &readfds, &writefds, &excfds, &max_fd);
 645
 646                         /*
 647                          * It can happen that curl_multi_timeout returns a pathologically
 648                          * long timeout when curl_multi_fdset returns no file descriptors
 649                          * to read.  See commit message for more details.
 650                          */
 651                         if (max_fd < 0 &&
 652                             (select_timeout.tv_sec > 0 ||
 653                              select_timeout.tv_usec > 50000)) {
 654                                 select_timeout.tv_sec  = 0;
 655                                 select_timeout.tv_usec = 50000;
 656                         }
 657
 658                         select(max_fd+1, &readfds, &writefds, &excfds, &select_timeout);
 659                 }
 660         }
 661 #else
 662         while (slot->in_use) {
 663                 slot->curl_result = curl_easy_perform(slot->curl);
 664                 finish_active_slot(slot);
 665         }
 666 #endif
 667 }
 668
 669 static void closedown_active_slot(struct active_request_slot *slot)
 670 {
 671         active_requests--;
 672         slot->in_use = 0;
 673 }
 674
 675 static void release_active_slot(struct active_request_slot *slot)
 676 {
 677         closedown_active_slot(slot);
 678         if (slot->curl && curl_session_count > min_curl_sessions) {
 679 #ifdef USE_CURL_MULTI
 680                 curl_multi_remove_handle(curlm, slot->curl);
 681 #endif
 682                 curl_easy_cleanup(slot->curl);
 683                 slot->curl = NULL;
 684                 curl_session_count--;
 685         }
 686 #ifdef USE_CURL_MULTI
 687         fill_active_slots();
 688 #endif
 689 }
 690
 691 void finish_active_slot(struct active_request_slot *slot)
 692 {
 693         closedown_active_slot(slot);
 694         curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
 695
 696         if (slot->finished != NULL)
 697                 (*slot->finished) = 1;
 698
 699         /* Store slot results so they can be read after the slot is reused */
 700         if (slot->results != NULL) {
 701                 slot->results->curl_result = slot->curl_result;
 702                 slot->results->http_code = slot->http_code;
 703         }
 704
 705         /* Run callback if appropriate */
 706         if (slot->callback_func != NULL)
 707                 slot->callback_func(slot->callback_data);
 708 }
 709
 710 void finish_all_active_slots(void)
 711 {
 712         struct active_request_slot *slot = active_queue_head;
 713
 714         while (slot != NULL)
 715                 if (slot->in_use) {
 716                         run_active_slot(slot);
 717                         slot = active_queue_head;
 718                 } else {
 719                         slot = slot->next;
 720                 }
 721 }
 722
 723 /* Helpers for modifying and creating URLs */
 724 static inline int needs_quote(int ch)
 725 {
 726         if (((ch >= 'A') && (ch <= 'Z'))
 727                         || ((ch >= 'a') && (ch <= 'z'))
 728                         || ((ch >= '0') && (ch <= '9'))
 729                         || (ch == '/')
 730                         || (ch == '-')
 731                         || (ch == '.'))
 732                 return 0;
 733         return 1;
 734 }
 735
 736 static char *quote_ref_url(const char *base, const char *ref)
 737 {
 738         struct strbuf buf = STRBUF_INIT;
 739         const char *cp;
 740         int ch;
 741
 742         end_url_with_slash(&buf, base);
 743
 744         for (cp = ref; (ch = *cp) != 0; cp++)
 745                 if (needs_quote(ch))
 746                         strbuf_addf(&buf, "%%%02x", ch);
 747                 else
 748                         strbuf_addch(&buf, *cp);
 749
 750         return strbuf_detach(&buf, NULL);
 751 }
 752
 753 void append_remote_object_url(struct strbuf *buf, const char *url,
 754                               const char *hex,
 755                               int only_two_digit_prefix)
 756 {
 757         end_url_with_slash(buf, url);
 758
 759         strbuf_addf(buf, "objects/%.*s/", 2, hex);
 760         if (!only_two_digit_prefix)
 761                 strbuf_addf(buf, "%s", hex+2);
 762 }
 763
 764 char *get_remote_object_url(const char *url, const char *hex,
 765                             int only_two_digit_prefix)
 766 {
 767         struct strbuf buf = STRBUF_INIT;
 768         append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
 769         return strbuf_detach(&buf, NULL);
 770 }
 771
 772 int handle_curl_result(struct slot_results *results)
 773 {
 774         /*
 775          * If we see a failing http code with CURLE_OK, we have turned off
 776          * FAILONERROR (to keep the server's custom error response), and should
 777          * translate the code into failure here.
 778          */
 779         if (results->curl_result == CURLE_OK &&
 780             results->http_code >= 400) {
 781                 results->curl_result = CURLE_HTTP_RETURNED_ERROR;
 782                 /*
 783                  * Normally curl will already have put the "reason phrase"
 784                  * from the server into curl_errorstr; unfortunately without
 785                  * FAILONERROR it is lost, so we can give only the numeric
 786                  * status code.
 787                  */
 788                 snprintf(curl_errorstr, sizeof(curl_errorstr),
 789                          "The requested URL returned error: %ld",
 790                          results->http_code);
 791         }
 792
 793         if (results->curl_result == CURLE_OK) {
 794                 credential_approve(&http_auth);
 795                 return HTTP_OK;
 796         } else if (missing_target(results))
 797                 return HTTP_MISSING_TARGET;
 798         else if (results->http_code == 401) {
 799                 if (http_auth.username && http_auth.password) {
 800                         credential_reject(&http_auth);
 801                         return HTTP_NOAUTH;
 802                 } else {
 803                         credential_fill(&http_auth);
 804                         return HTTP_REAUTH;
 805                 }
 806         } else {
 807 #if LIBCURL_VERSION_NUM >= 0x070c00
 808                 if (!curl_errorstr[0])
 809                         strlcpy(curl_errorstr,
 810                                 curl_easy_strerror(results->curl_result),
 811                                 sizeof(curl_errorstr));
 812 #endif
 813                 return HTTP_ERROR;
 814         }
 815 }
 816
 817 /* http_request() targets */
 818 #define HTTP_REQUEST_STRBUF     0
 819 #define HTTP_REQUEST_FILE       1
 820
 821 static int http_request(const char *url, struct strbuf *type,
 822                         void *result, int target, int options)
 823 {
 824         struct active_request_slot *slot;
 825         struct slot_results results;
 826         struct curl_slist *headers = NULL;
 827         struct strbuf buf = STRBUF_INIT;
 828         int ret;
 829
 830         slot = get_active_slot();
 831         slot->results = &results;
 832         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 833
 834         if (result == NULL) {
 835                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
 836         } else {
 837                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
 838                 curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
 839
 840                 if (target == HTTP_REQUEST_FILE) {
 841                         long posn = ftell(result);
 842                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
 843                                          fwrite);
 844                         if (posn > 0) {
 845                                 strbuf_addf(&buf, "Range: bytes=%ld-", posn);
 846                                 headers = curl_slist_append(headers, buf.buf);
 847                                 strbuf_reset(&buf);
 848                         }
 849                 } else
 850                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
 851                                          fwrite_buffer);
 852         }
 853
 854         strbuf_addstr(&buf, "Pragma:");
 855         if (options & HTTP_NO_CACHE)
 856                 strbuf_addstr(&buf, " no-cache");
 857         if (options & HTTP_KEEP_ERROR)
 858                 curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
 859
 860         headers = curl_slist_append(headers, buf.buf);
 861
 862         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
 863         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
 864         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "gzip");
 865
 866         if (start_active_slot(slot)) {
 867                 run_active_slot(slot);
 868                 ret = handle_curl_result(&results);
 869         } else {
 870                 snprintf(curl_errorstr, sizeof(curl_errorstr),
 871                          "failed to start HTTP request");
 872                 ret = HTTP_START_FAILED;
 873         }
 874
 875         if (type) {
 876                 char *t;
 877                 strbuf_reset(type);
 878                 curl_easy_getinfo(slot->curl, CURLINFO_CONTENT_TYPE, &t);
 879                 if (t)
 880                         strbuf_addstr(type, t);
 881         }
 882
 883         curl_slist_free_all(headers);
 884         strbuf_release(&buf);
 885
 886         return ret;
 887 }
 888
 889 static int http_request_reauth(const char *url,
 890                                struct strbuf *type,
 891                                void *result, int target,
 892                                int options)
 893 {
 894         int ret = http_request(url, type, result, target, options);
 895         if (ret != HTTP_REAUTH)
 896                 return ret;
 897
 898         /*
 899          * If we are using KEEP_ERROR, the previous request may have
 900          * put cruft into our output stream; we should clear it out before
 901          * making our next request. We only know how to do this for
 902          * the strbuf case, but that is enough to satisfy current callers.
 903          */
 904         if (options & HTTP_KEEP_ERROR) {
 905                 switch (target) {
 906                 case HTTP_REQUEST_STRBUF:
 907                         strbuf_reset(result);
 908                         break;
 909                 default:
 910                         die("BUG: HTTP_KEEP_ERROR is only supported with strbufs");
 911                 }
 912         }
 913         return http_request(url, type, result, target, options);
 914 }
 915
 916 int http_get_strbuf(const char *url,
 917                     struct strbuf *type,
 918                     struct strbuf *result, int options)
 919 {
 920         return http_request_reauth(url, type, result,
 921                                    HTTP_REQUEST_STRBUF, options);
 922 }
 923
 924 /*
 925  * Downloads a URL and stores the result in the given file.
 926  *
 927  * If a previous interrupted download is detected (i.e. a previous temporary
 928  * file is still around) the download is resumed.
 929  */
 930 static int http_get_file(const char *url, const char *filename, int options)
 931 {
 932         int ret;
 933         struct strbuf tmpfile = STRBUF_INIT;
 934         FILE *result;
 935
 936         strbuf_addf(&tmpfile, "%s.temp", filename);
 937         result = fopen(tmpfile.buf, "a");
 938         if (! result) {
 939                 error("Unable to open local file %s", tmpfile.buf);
 940                 ret = HTTP_ERROR;
 941                 goto cleanup;
 942         }
 943
 944         ret = http_request_reauth(url, NULL, result, HTTP_REQUEST_FILE, options);
 945         fclose(result);
 946
 947         if ((ret == HTTP_OK) && move_temp_to_file(tmpfile.buf, filename))
 948                 ret = HTTP_ERROR;
 949 cleanup:
 950         strbuf_release(&tmpfile);
 951         return ret;
 952 }
 953
 954 int http_fetch_ref(const char *base, struct ref *ref)
 955 {
 956         char *url;
 957         struct strbuf buffer = STRBUF_INIT;
 958         int ret = -1;
 959
 960         url = quote_ref_url(base, ref->name);
 961         if (http_get_strbuf(url, NULL, &buffer, HTTP_NO_CACHE) == HTTP_OK) {
 962                 strbuf_rtrim(&buffer);
 963                 if (buffer.len == 40)
 964                         ret = get_sha1_hex(buffer.buf, ref->old_sha1);
 965                 else if (!prefixcmp(buffer.buf, "ref: ")) {
 966                         ref->symref = xstrdup(buffer.buf + 5);
 967                         ret = 0;
 968                 }
 969         }
 970
 971         strbuf_release(&buffer);
 972         free(url);
 973         return ret;
 974 }
 975
 976 /* Helpers for fetching packs */
 977 static char *fetch_pack_index(unsigned char *sha1, const char *base_url)
 978 {
 979         char *url, *tmp;
 980         struct strbuf buf = STRBUF_INIT;
 981
 982         if (http_is_verbose)
 983                 fprintf(stderr, "Getting index for pack %s\n", sha1_to_hex(sha1));
 984
 985         end_url_with_slash(&buf, base_url);
 986         strbuf_addf(&buf, "objects/pack/pack-%s.idx", sha1_to_hex(sha1));
 987         url = strbuf_detach(&buf, NULL);
 988
 989         strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(sha1));
 990         tmp = strbuf_detach(&buf, NULL);
 991
 992         if (http_get_file(url, tmp, 0) != HTTP_OK) {
 993                 error("Unable to get pack index %s", url);
 994                 free(tmp);
 995                 tmp = NULL;
 996         }
 997
 998         free(url);
 999         return tmp;
1000 }
1001
1002 static int fetch_and_setup_pack_index(struct packed_git **packs_head,
1003         unsigned char *sha1, const char *base_url)
1004 {
1005         struct packed_git *new_pack;
1006         char *tmp_idx = NULL;
1007         int ret;
1008
1009         if (has_pack_index(sha1)) {
1010                 new_pack = parse_pack_index(sha1, NULL);
1011                 if (!new_pack)
1012                         return -1; /* parse_pack_index() already issued error message */
1013                 goto add_pack;
1014         }
1015
1016         tmp_idx = fetch_pack_index(sha1, base_url);
1017         if (!tmp_idx)
1018                 return -1;
1019
1020         new_pack = parse_pack_index(sha1, tmp_idx);
1021         if (!new_pack) {
1022                 unlink(tmp_idx);
1023                 free(tmp_idx);
1024
1025                 return -1; /* parse_pack_index() already issued error message */
1026         }
1027
1028         ret = verify_pack_index(new_pack);
1029         if (!ret) {
1030                 close_pack_index(new_pack);
1031                 ret = move_temp_to_file(tmp_idx, sha1_pack_index_name(sha1));
1032         }
1033         free(tmp_idx);
1034         if (ret)
1035                 return -1;
1036
1037 add_pack:
1038         new_pack->next = *packs_head;
1039         *packs_head = new_pack;
1040         return 0;
1041 }
1042
1043 int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
1044 {
1045         int ret = 0, i = 0;
1046         char *url, *data;
1047         struct strbuf buf = STRBUF_INIT;
1048         unsigned char sha1[20];
1049
1050         end_url_with_slash(&buf, base_url);
1051         strbuf_addstr(&buf, "objects/info/packs");
1052         url = strbuf_detach(&buf, NULL);
1053
1054         ret = http_get_strbuf(url, NULL, &buf, HTTP_NO_CACHE);
1055         if (ret != HTTP_OK)
1056                 goto cleanup;
1057
1058         data = buf.buf;
1059         while (i < buf.len) {
1060                 switch (data[i]) {
1061                 case 'P':
1062                         i++;
1063                         if (i + 52 <= buf.len &&
1064                             !prefixcmp(data + i, " pack-") &&
1065                             !prefixcmp(data + i + 46, ".pack\n")) {
1066                                 get_sha1_hex(data + i + 6, sha1);
1067                                 fetch_and_setup_pack_index(packs_head, sha1,
1068                                                       base_url);
1069                                 i += 51;
1070                                 break;
1071                         }
1072                 default:
1073                         while (i < buf.len && data[i] != '\n')
1074                                 i++;
1075                 }
1076                 i++;
1077         }
1078
1079 cleanup:
1080         free(url);
1081         return ret;
1082 }
1083
1084 void release_http_pack_request(struct http_pack_request *preq)
1085 {
1086         if (preq->packfile != NULL) {
1087                 fclose(preq->packfile);
1088                 preq->packfile = NULL;
1089         }
1090         if (preq->range_header != NULL) {
1091                 curl_slist_free_all(preq->range_header);
1092                 preq->range_header = NULL;
1093         }
1094         preq->slot = NULL;
1095         free(preq->url);
1096 }
1097
1098 int finish_http_pack_request(struct http_pack_request *preq)
1099 {
1100         struct packed_git **lst;
1101         struct packed_git *p = preq->target;
1102         char *tmp_idx;
1103         struct child_process ip;
1104         const char *ip_argv[8];
1105
1106         close_pack_index(p);
1107
1108         fclose(preq->packfile);
1109         preq->packfile = NULL;
1110
1111         lst = preq->lst;
1112         while (*lst != p)
1113                 lst = &((*lst)->next);
1114         *lst = (*lst)->next;
1115
1116         tmp_idx = xstrdup(preq->tmpfile);
1117         strcpy(tmp_idx + strlen(tmp_idx) - strlen(".pack.temp"),
1118                ".idx.temp");
1119
1120         ip_argv[0] = "index-pack";
1121         ip_argv[1] = "-o";
1122         ip_argv[2] = tmp_idx;
1123         ip_argv[3] = preq->tmpfile;
1124         ip_argv[4] = NULL;
1125
1126         memset(&ip, 0, sizeof(ip));
1127         ip.argv = ip_argv;
1128         ip.git_cmd = 1;
1129         ip.no_stdin = 1;
1130         ip.no_stdout = 1;
1131
1132         if (run_command(&ip)) {
1133                 unlink(preq->tmpfile);
1134                 unlink(tmp_idx);
1135                 free(tmp_idx);
1136                 return -1;
1137         }
1138
1139         unlink(sha1_pack_index_name(p->sha1));
1140
1141         if (move_temp_to_file(preq->tmpfile, sha1_pack_name(p->sha1))
1142          || move_temp_to_file(tmp_idx, sha1_pack_index_name(p->sha1))) {
1143                 free(tmp_idx);
1144                 return -1;
1145         }
1146
1147         install_packed_git(p);
1148         free(tmp_idx);
1149         return 0;
1150 }
1151
1152 struct http_pack_request *new_http_pack_request(
1153         struct packed_git *target, const char *base_url)
1154 {
1155         long prev_posn = 0;
1156         char range[RANGE_HEADER_SIZE];
1157         struct strbuf buf = STRBUF_INIT;
1158         struct http_pack_request *preq;
1159
1160         preq = xcalloc(1, sizeof(*preq));
1161         preq->target = target;
1162
1163         end_url_with_slash(&buf, base_url);
1164         strbuf_addf(&buf, "objects/pack/pack-%s.pack",
1165                 sha1_to_hex(target->sha1));
1166         preq->url = strbuf_detach(&buf, NULL);
1167
1168         snprintf(preq->tmpfile, sizeof(preq->tmpfile), "%s.temp",
1169                 sha1_pack_name(target->sha1));
1170         preq->packfile = fopen(preq->tmpfile, "a");
1171         if (!preq->packfile) {
1172                 error("Unable to open local file %s for pack",
1173                       preq->tmpfile);
1174                 goto abort;
1175         }
1176
1177         preq->slot = get_active_slot();
1178         curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
1179         curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
1180         curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
1181         curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1182                 no_pragma_header);
1183
1184         /*
1185          * If there is data present from a previous transfer attempt,
1186          * resume where it left off
1187          */
1188         prev_posn = ftell(preq->packfile);
1189         if (prev_posn>0) {
1190                 if (http_is_verbose)
1191                         fprintf(stderr,
1192                                 "Resuming fetch of pack %s at byte %ld\n",
1193                                 sha1_to_hex(target->sha1), prev_posn);
1194                 sprintf(range, "Range: bytes=%ld-", prev_posn);
1195                 preq->range_header = curl_slist_append(NULL, range);
1196                 curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1197                         preq->range_header);
1198         }
1199
1200         return preq;
1201
1202 abort:
1203         free(preq->url);
1204         free(preq);
1205         return NULL;
1206 }
1207
1208 /* Helpers for fetching objects (loose) */
1209 static size_t fwrite_sha1_file(char *ptr, size_t eltsize, size_t nmemb,
1210                                void *data)
1211 {
1212         unsigned char expn[4096];
1213         size_t size = eltsize * nmemb;
1214         int posn = 0;
1215         struct http_object_request *freq =
1216                 (struct http_object_request *)data;
1217         do {
1218                 ssize_t retval = xwrite(freq->localfile,
1219                                         (char *) ptr + posn, size - posn);
1220                 if (retval < 0)
1221                         return posn;
1222                 posn += retval;
1223         } while (posn < size);
1224
1225         freq->stream.avail_in = size;
1226         freq->stream.next_in = (void *)ptr;
1227         do {
1228                 freq->stream.next_out = expn;
1229                 freq->stream.avail_out = sizeof(expn);
1230                 freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
1231                 git_SHA1_Update(&freq->c, expn,
1232                                 sizeof(expn) - freq->stream.avail_out);
1233         } while (freq->stream.avail_in && freq->zret == Z_OK);
1234         return size;
1235 }
1236
1237 struct http_object_request *new_http_object_request(const char *base_url,
1238         unsigned char *sha1)
1239 {
1240         char *hex = sha1_to_hex(sha1);
1241         char *filename;
1242         char prevfile[PATH_MAX];
1243         int prevlocal;
1244         char prev_buf[PREV_BUF_SIZE];
1245         ssize_t prev_read = 0;
1246         long prev_posn = 0;
1247         char range[RANGE_HEADER_SIZE];
1248         struct curl_slist *range_header = NULL;
1249         struct http_object_request *freq;
1250
1251         freq = xcalloc(1, sizeof(*freq));
1252         hashcpy(freq->sha1, sha1);
1253         freq->localfile = -1;
1254
1255         filename = sha1_file_name(sha1);
1256         snprintf(freq->tmpfile, sizeof(freq->tmpfile),
1257                  "%s.temp", filename);
1258
1259         snprintf(prevfile, sizeof(prevfile), "%s.prev", filename);
1260         unlink_or_warn(prevfile);
1261         rename(freq->tmpfile, prevfile);
1262         unlink_or_warn(freq->tmpfile);
1263
1264         if (freq->localfile != -1)
1265                 error("fd leakage in start: %d", freq->localfile);
1266         freq->localfile = open(freq->tmpfile,
1267                                O_WRONLY | O_CREAT | O_EXCL, 0666);
1268         /*
1269          * This could have failed due to the "lazy directory creation";
1270          * try to mkdir the last path component.
1271          */
1272         if (freq->localfile < 0 && errno == ENOENT) {
1273                 char *dir = strrchr(freq->tmpfile, '/');
1274                 if (dir) {
1275                         *dir = 0;
1276                         mkdir(freq->tmpfile, 0777);
1277                         *dir = '/';
1278                 }
1279                 freq->localfile = open(freq->tmpfile,
1280                                        O_WRONLY | O_CREAT | O_EXCL, 0666);
1281         }
1282
1283         if (freq->localfile < 0) {
1284                 error("Couldn't create temporary file %s: %s",
1285                       freq->tmpfile, strerror(errno));
1286                 goto abort;
1287         }
1288
1289         git_inflate_init(&freq->stream);
1290
1291         git_SHA1_Init(&freq->c);
1292
1293         freq->url = get_remote_object_url(base_url, hex, 0);
1294
1295         /*
1296          * If a previous temp file is present, process what was already
1297          * fetched.
1298          */
1299         prevlocal = open(prevfile, O_RDONLY);
1300         if (prevlocal != -1) {
1301                 do {
1302                         prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
1303                         if (prev_read>0) {
1304                                 if (fwrite_sha1_file(prev_buf,
1305                                                      1,
1306                                                      prev_read,
1307                                                      freq) == prev_read) {
1308                                         prev_posn += prev_read;
1309                                 } else {
1310                                         prev_read = -1;
1311                                 }
1312                         }
1313                 } while (prev_read > 0);
1314                 close(prevlocal);
1315         }
1316         unlink_or_warn(prevfile);
1317
1318         /*
1319          * Reset inflate/SHA1 if there was an error reading the previous temp
1320          * file; also rewind to the beginning of the local file.
1321          */
1322         if (prev_read == -1) {
1323                 memset(&freq->stream, 0, sizeof(freq->stream));
1324                 git_inflate_init(&freq->stream);
1325                 git_SHA1_Init(&freq->c);
1326                 if (prev_posn>0) {
1327                         prev_posn = 0;
1328                         lseek(freq->localfile, 0, SEEK_SET);
1329                         if (ftruncate(freq->localfile, 0) < 0) {
1330                                 error("Couldn't truncate temporary file %s: %s",
1331                                           freq->tmpfile, strerror(errno));
1332                                 goto abort;
1333                         }
1334                 }
1335         }
1336
1337         freq->slot = get_active_slot();
1338
1339         curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
1340         curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
1341         curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
1342         curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
1343         curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
1344
1345         /*
1346          * If we have successfully processed data from a previous fetch
1347          * attempt, only fetch the data we don't already have.
1348          */
1349         if (prev_posn>0) {
1350                 if (http_is_verbose)
1351                         fprintf(stderr,
1352                                 "Resuming fetch of object %s at byte %ld\n",
1353                                 hex, prev_posn);
1354                 sprintf(range, "Range: bytes=%ld-", prev_posn);
1355                 range_header = curl_slist_append(range_header, range);
1356                 curl_easy_setopt(freq->slot->curl,
1357                                  CURLOPT_HTTPHEADER, range_header);
1358         }
1359
1360         return freq;
1361
1362 abort:
1363         free(freq->url);
1364         free(freq);
1365         return NULL;
1366 }
1367
1368 void process_http_object_request(struct http_object_request *freq)
1369 {
1370         if (freq->slot == NULL)
1371                 return;
1372         freq->curl_result = freq->slot->curl_result;
1373         freq->http_code = freq->slot->http_code;
1374         freq->slot = NULL;
1375 }
1376
1377 int finish_http_object_request(struct http_object_request *freq)
1378 {
1379         struct stat st;
1380
1381         close(freq->localfile);
1382         freq->localfile = -1;
1383
1384         process_http_object_request(freq);
1385
1386         if (freq->http_code == 416) {
1387                 warning("requested range invalid; we may already have all the data.");
1388         } else if (freq->curl_result != CURLE_OK) {
1389                 if (stat(freq->tmpfile, &st) == 0)
1390                         if (st.st_size == 0)
1391                                 unlink_or_warn(freq->tmpfile);
1392                 return -1;
1393         }
1394
1395         git_inflate_end(&freq->stream);
1396         git_SHA1_Final(freq->real_sha1, &freq->c);
1397         if (freq->zret != Z_STREAM_END) {
1398                 unlink_or_warn(freq->tmpfile);
1399                 return -1;
1400         }
1401         if (hashcmp(freq->sha1, freq->real_sha1)) {
1402                 unlink_or_warn(freq->tmpfile);
1403                 return -1;
1404         }
1405         freq->rename =
1406                 move_temp_to_file(freq->tmpfile, sha1_file_name(freq->sha1));
1407
1408         return freq->rename;
1409 }
1410
1411 void abort_http_object_request(struct http_object_request *freq)
1412 {
1413         unlink_or_warn(freq->tmpfile);
1414
1415         release_http_object_request(freq);
1416 }
1417
1418 void release_http_object_request(struct http_object_request *freq)
1419 {
1420         if (freq->localfile != -1) {
1421                 close(freq->localfile);
1422                 freq->localfile = -1;
1423         }
1424         if (freq->url != NULL) {
1425                 free(freq->url);
1426                 freq->url = NULL;
1427         }
1428         if (freq->slot != NULL) {
1429                 freq->slot->callback_func = NULL;
1430                 freq->slot->callback_data = NULL;
1431                 release_active_slot(freq->slot);
1432                 freq->slot = NULL;
1433         }
1434 }