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