http.c

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