http.c

   1 #include "http.h"
   2 #include "pack.h"
   3 #include "sideband.h"
   4 #include "run-command.h"
   5 #include "url.h"
   6
   7 int data_received;
   8 int active_requests;
   9 int http_is_verbose;
  10 size_t http_post_buffer = 16 * LARGE_PACKET_MAX;
  11
  12 #if LIBCURL_VERSION_NUM >= 0x070a06
  13 #define LIBCURL_CAN_HANDLE_AUTH_ANY
  14 #endif
  15
  16 static int min_curl_sessions = 1;
  17 static int curl_session_count;
  18 #ifdef USE_CURL_MULTI
  19 static int max_requests = -1;
  20 static CURLM *curlm;
  21 #endif
  22 #ifndef NO_CURL_EASY_DUPHANDLE
  23 static CURL *curl_default;
  24 #endif
  25
  26 #define PREV_BUF_SIZE 4096
  27 #define RANGE_HEADER_SIZE 30
  28
  29 char curl_errorstr[CURL_ERROR_SIZE];
  30
  31 static int curl_ssl_verify = -1;
  32 static const char *ssl_cert;
  33 #if LIBCURL_VERSION_NUM >= 0x070903
  34 static const char *ssl_key;
  35 #endif
  36 #if LIBCURL_VERSION_NUM >= 0x070908
  37 static const char *ssl_capath;
  38 #endif
  39 static const char *ssl_cainfo;
  40 static long curl_low_speed_limit = -1;
  41 static long curl_low_speed_time = -1;
  42 static int curl_ftp_no_epsv;
  43 static const char *curl_http_proxy;
  44 static char *user_name, *user_pass;
  45 static const char *user_agent;
  46
  47 #if LIBCURL_VERSION_NUM >= 0x071700
  48 /* Use CURLOPT_KEYPASSWD as is */
  49 #elif LIBCURL_VERSION_NUM >= 0x070903
  50 #define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
  51 #else
  52 #define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
  53 #endif
  54
  55 static char *ssl_cert_password;
  56 static int ssl_cert_password_required;
  57
  58 static struct curl_slist *pragma_header;
  59 static struct curl_slist *no_pragma_header;
  60
  61 static struct active_request_slot *active_queue_head;
  62
  63 size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
  64 {
  65         size_t size = eltsize * nmemb;
  66         struct buffer *buffer = buffer_;
  67
  68         if (size > buffer->buf.len - buffer->posn)
  69                 size = buffer->buf.len - buffer->posn;
  70         memcpy(ptr, buffer->buf.buf + buffer->posn, size);
  71         buffer->posn += size;
  72
  73         return size;
  74 }
  75
  76 #ifndef NO_CURL_IOCTL
  77 curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
  78 {
  79         struct buffer *buffer = clientp;
  80
  81         switch (cmd) {
  82         case CURLIOCMD_NOP:
  83                 return CURLIOE_OK;
  84
  85         case CURLIOCMD_RESTARTREAD:
  86                 buffer->posn = 0;
  87                 return CURLIOE_OK;
  88
  89         default:
  90                 return CURLIOE_UNKNOWNCMD;
  91         }
  92 }
  93 #endif
  94
  95 size_t fwrite_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
  96 {
  97         size_t size = eltsize * nmemb;
  98         struct strbuf *buffer = buffer_;
  99
 100         strbuf_add(buffer, ptr, size);
 101         data_received++;
 102         return size;
 103 }
 104
 105 size_t fwrite_null(char *ptr, size_t eltsize, size_t nmemb, void *strbuf)
 106 {
 107         data_received++;
 108         return eltsize * nmemb;
 109 }
 110
 111 #ifdef USE_CURL_MULTI
 112 static void process_curl_messages(void)
 113 {
 114         int num_messages;
 115         struct active_request_slot *slot;
 116         CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
 117
 118         while (curl_message != NULL) {
 119                 if (curl_message->msg == CURLMSG_DONE) {
 120                         int curl_result = curl_message->data.result;
 121                         slot = active_queue_head;
 122                         while (slot != NULL &&
 123                                slot->curl != curl_message->easy_handle)
 124                                 slot = slot->next;
 125                         if (slot != NULL) {
 126                                 curl_multi_remove_handle(curlm, slot->curl);
 127                                 slot->curl_result = curl_result;
 128                                 finish_active_slot(slot);
 129                         } else {
 130                                 fprintf(stderr, "Received DONE message for unknown request!\n");
 131                         }
 132                 } else {
 133                         fprintf(stderr, "Unknown CURL message received: %d\n",
 134                                 (int)curl_message->msg);
 135                 }
 136                 curl_message = curl_multi_info_read(curlm, &num_messages);
 137         }
 138 }
 139 #endif
 140
 141 static int http_options(const char *var, const char *value, void *cb)
 142 {
 143         if (!strcmp("http.sslverify", var)) {
 144                 curl_ssl_verify = git_config_bool(var, value);
 145                 return 0;
 146         }
 147         if (!strcmp("http.sslcert", var))
 148                 return git_config_string(&ssl_cert, var, value);
 149 #if LIBCURL_VERSION_NUM >= 0x070903
 150         if (!strcmp("http.sslkey", var))
 151                 return git_config_string(&ssl_key, var, value);
 152 #endif
 153 #if LIBCURL_VERSION_NUM >= 0x070908
 154         if (!strcmp("http.sslcapath", var))
 155                 return git_config_string(&ssl_capath, var, value);
 156 #endif
 157         if (!strcmp("http.sslcainfo", var))
 158                 return git_config_string(&ssl_cainfo, var, value);
 159         if (!strcmp("http.sslcertpasswordprotected", var)) {
 160                 if (git_config_bool(var, value))
 161                         ssl_cert_password_required = 1;
 162                 return 0;
 163         }
 164         if (!strcmp("http.minsessions", var)) {
 165                 min_curl_sessions = git_config_int(var, value);
 166 #ifndef USE_CURL_MULTI
 167                 if (min_curl_sessions > 1)
 168                         min_curl_sessions = 1;
 169 #endif
 170                 return 0;
 171         }
 172 #ifdef USE_CURL_MULTI
 173         if (!strcmp("http.maxrequests", var)) {
 174                 max_requests = git_config_int(var, value);
 175                 return 0;
 176         }
 177 #endif
 178         if (!strcmp("http.lowspeedlimit", var)) {
 179                 curl_low_speed_limit = (long)git_config_int(var, value);
 180                 return 0;
 181         }
 182         if (!strcmp("http.lowspeedtime", var)) {
 183                 curl_low_speed_time = (long)git_config_int(var, value);
 184                 return 0;
 185         }
 186
 187         if (!strcmp("http.noepsv", var)) {
 188                 curl_ftp_no_epsv = git_config_bool(var, value);
 189                 return 0;
 190         }
 191         if (!strcmp("http.proxy", var))
 192                 return git_config_string(&curl_http_proxy, var, value);
 193
 194         if (!strcmp("http.postbuffer", var)) {
 195                 http_post_buffer = git_config_int(var, value);
 196                 if (http_post_buffer < LARGE_PACKET_MAX)
 197                         http_post_buffer = LARGE_PACKET_MAX;
 198                 return 0;
 199         }
 200
 201         if (!strcmp("http.useragent", var))
 202                 return git_config_string(&user_agent, var, value);
 203
 204         /* Fall back on the default ones */
 205         return git_default_config(var, value, cb);
 206 }
 207
 208 static void init_curl_http_auth(CURL *result)
 209 {
 210         if (user_name) {
 211                 struct strbuf up = STRBUF_INIT;
 212                 if (!user_pass)
 213                         user_pass = xstrdup(git_getpass("Password: "));
 214                 strbuf_addf(&up, "%s:%s", user_name, user_pass);
 215                 curl_easy_setopt(result, CURLOPT_USERPWD,
 216                                  strbuf_detach(&up, NULL));
 217         }
 218 }
 219
 220 static int has_cert_password(void)
 221 {
 222         if (ssl_cert_password != NULL)
 223                 return 1;
 224         if (ssl_cert == NULL || ssl_cert_password_required != 1)
 225                 return 0;
 226         /* Only prompt the user once. */
 227         ssl_cert_password_required = -1;
 228         ssl_cert_password = git_getpass("Certificate Password: ");
 229         if (ssl_cert_password != NULL) {
 230                 ssl_cert_password = xstrdup(ssl_cert_password);
 231                 return 1;
 232         } else
 233                 return 0;
 234 }
 235
 236 /* curl 7.25.0 has CURLOPT_TCP_KEEPALIVE, too, but we support older curl */
 237 static int sockopt_callback(void *client, curl_socket_t fd, curlsocktype type)
 238 {
 239         int ka = 1;
 240         int rc;
 241         socklen_t len = (socklen_t)sizeof(ka);
 242
 243         if (type != CURLSOCKTYPE_IPCXN)
 244                 return 0;
 245
 246         rc = setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&ka, len);
 247         if (rc < 0)
 248                 warning("unable to set SO_KEEPALIVE on socket %s",
 249                         strerror(errno));
 250
 251         return 0; /* CURL_SOCKOPT_OK only exists since curl 7.21.5 */
 252 }
 253
 254 static CURL *get_curl_handle(void)
 255 {
 256         CURL *result = curl_easy_init();
 257
 258         if (!curl_ssl_verify) {
 259                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
 260                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
 261         } else {
 262                 /* Verify authenticity of the peer's certificate */
 263                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
 264                 /* The name in the cert must match whom we tried to connect */
 265                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
 266         }
 267
 268 #if LIBCURL_VERSION_NUM >= 0x070907
 269         curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
 270 #endif
 271 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 272         curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 273 #endif
 274
 275         init_curl_http_auth(result);
 276
 277         if (ssl_cert != NULL)
 278                 curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
 279         if (has_cert_password())
 280                 curl_easy_setopt(result, CURLOPT_KEYPASSWD, ssl_cert_password);
 281 #if LIBCURL_VERSION_NUM >= 0x070903
 282         if (ssl_key != NULL)
 283                 curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
 284 #endif
 285 #if LIBCURL_VERSION_NUM >= 0x070908
 286         if (ssl_capath != NULL)
 287                 curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
 288 #endif
 289         if (ssl_cainfo != NULL)
 290                 curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
 291         curl_easy_setopt(result, CURLOPT_FAILONERROR, 1);
 292
 293         if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
 294                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
 295                                  curl_low_speed_limit);
 296                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
 297                                  curl_low_speed_time);
 298         }
 299
 300         curl_easy_setopt(result, CURLOPT_FOLLOWLOCATION, 1);
 301 #if LIBCURL_VERSION_NUM >= 0x071301
 302         curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
 303 #elif LIBCURL_VERSION_NUM >= 0x071101
 304         curl_easy_setopt(result, CURLOPT_POST301, 1);
 305 #endif
 306
 307         if (getenv("GIT_CURL_VERBOSE"))
 308                 curl_easy_setopt(result, CURLOPT_VERBOSE, 1);
 309
 310         curl_easy_setopt(result, CURLOPT_USERAGENT,
 311                 user_agent ? user_agent : GIT_HTTP_USER_AGENT);
 312
 313         if (curl_ftp_no_epsv)
 314                 curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
 315
 316         if (curl_http_proxy)
 317                 curl_easy_setopt(result, CURLOPT_PROXY, curl_http_proxy);
 318
 319 #if LIBCURL_VERSION_NUM >= 0x071000
 320         curl_easy_setopt(result, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
 321 #endif
 322
 323         return result;
 324 }
 325
 326 static void http_auth_init(const char *url)
 327 {
 328         char *at, *colon, *cp, *slash, *decoded;
 329         int len;
 330
 331         cp = strstr(url, "://");
 332         if (!cp)
 333                 return;
 334
 335         /*
 336          * Ok, the URL looks like "proto://something".  Which one?
 337          * "proto://<user>:<pass>@<host>/...",
 338          * "proto://<user>@<host>/...", or just
 339          * "proto://<host>/..."?
 340          */
 341         cp += 3;
 342         at = strchr(cp, '@');
 343         colon = strchr(cp, ':');
 344         slash = strchrnul(cp, '/');
 345         if (!at || slash <= at)
 346                 return; /* No credentials */
 347         if (!colon || at <= colon) {
 348                 /* Only username */
 349                 len = at - cp;
 350                 user_name = xmalloc(len + 1);
 351                 memcpy(user_name, cp, len);
 352                 user_name[len] = '\0';
 353                 decoded = url_decode(user_name);
 354                 free(user_name);
 355                 user_name = decoded;
 356                 user_pass = NULL;
 357         } else {
 358                 len = colon - cp;
 359                 user_name = xmalloc(len + 1);
 360                 memcpy(user_name, cp, len);
 361                 user_name[len] = '\0';
 362                 decoded = url_decode(user_name);
 363                 free(user_name);
 364                 user_name = decoded;
 365                 len = at - (colon + 1);
 366                 user_pass = xmalloc(len + 1);
 367                 memcpy(user_pass, colon + 1, len);
 368                 user_pass[len] = '\0';
 369                 decoded = url_decode(user_pass);
 370                 free(user_pass);
 371                 user_pass = decoded;
 372         }
 373 }
 374
 375 static void set_from_env(const char **var, const char *envname)
 376 {
 377         const char *val = getenv(envname);
 378         if (val)
 379                 *var = val;
 380 }
 381
 382 void http_init(struct remote *remote)
 383 {
 384         char *low_speed_limit;
 385         char *low_speed_time;
 386
 387         http_is_verbose = 0;
 388
 389         git_config(http_options, NULL);
 390
 391         curl_global_init(CURL_GLOBAL_ALL);
 392
 393         if (remote && remote->http_proxy)
 394                 curl_http_proxy = xstrdup(remote->http_proxy);
 395
 396         pragma_header = curl_slist_append(pragma_header, "Pragma: no-cache");
 397         no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
 398
 399 #ifdef USE_CURL_MULTI
 400         {
 401                 char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
 402                 if (http_max_requests != NULL)
 403                         max_requests = atoi(http_max_requests);
 404         }
 405
 406         curlm = curl_multi_init();
 407         if (curlm == NULL) {
 408                 fprintf(stderr, "Error creating curl multi handle.\n");
 409                 exit(1);
 410         }
 411 #endif
 412
 413         if (getenv("GIT_SSL_NO_VERIFY"))
 414                 curl_ssl_verify = 0;
 415
 416         set_from_env(&ssl_cert, "GIT_SSL_CERT");
 417 #if LIBCURL_VERSION_NUM >= 0x070903
 418         set_from_env(&ssl_key, "GIT_SSL_KEY");
 419 #endif
 420 #if LIBCURL_VERSION_NUM >= 0x070908
 421         set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
 422 #endif
 423         set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
 424
 425         set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
 426
 427         low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
 428         if (low_speed_limit != NULL)
 429                 curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
 430         low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
 431         if (low_speed_time != NULL)
 432                 curl_low_speed_time = strtol(low_speed_time, NULL, 10);
 433
 434         if (curl_ssl_verify == -1)
 435                 curl_ssl_verify = 1;
 436
 437         curl_session_count = 0;
 438 #ifdef USE_CURL_MULTI
 439         if (max_requests < 1)
 440                 max_requests = DEFAULT_MAX_REQUESTS;
 441 #endif
 442
 443         if (getenv("GIT_CURL_FTP_NO_EPSV"))
 444                 curl_ftp_no_epsv = 1;
 445
 446         if (remote && remote->url && remote->url[0]) {
 447                 http_auth_init(remote->url[0]);
 448                 if (!ssl_cert_password_required &&
 449                     getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
 450                     !prefixcmp(remote->url[0], "https://"))
 451                         ssl_cert_password_required = 1;
 452         }
 453
 454 #ifndef NO_CURL_EASY_DUPHANDLE
 455         curl_default = get_curl_handle();
 456 #endif
 457 }
 458
 459 void http_cleanup(void)
 460 {
 461         struct active_request_slot *slot = active_queue_head;
 462
 463         while (slot != NULL) {
 464                 struct active_request_slot *next = slot->next;
 465                 if (slot->curl != NULL) {
 466 #ifdef USE_CURL_MULTI
 467                         curl_multi_remove_handle(curlm, slot->curl);
 468 #endif
 469                         curl_easy_cleanup(slot->curl);
 470                 }
 471                 free(slot);
 472                 slot = next;
 473         }
 474         active_queue_head = NULL;
 475
 476 #ifndef NO_CURL_EASY_DUPHANDLE
 477         curl_easy_cleanup(curl_default);
 478 #endif
 479
 480 #ifdef USE_CURL_MULTI
 481         curl_multi_cleanup(curlm);
 482 #endif
 483         curl_global_cleanup();
 484
 485         curl_slist_free_all(pragma_header);
 486         pragma_header = NULL;
 487
 488         curl_slist_free_all(no_pragma_header);
 489         no_pragma_header = NULL;
 490
 491         if (curl_http_proxy) {
 492                 free((void *)curl_http_proxy);
 493                 curl_http_proxy = NULL;
 494         }
 495
 496         if (ssl_cert_password != NULL) {
 497                 memset(ssl_cert_password, 0, strlen(ssl_cert_password));
 498                 free(ssl_cert_password);
 499                 ssl_cert_password = NULL;
 500         }
 501         ssl_cert_password_required = 0;
 502 }
 503
 504 struct active_request_slot *get_active_slot(void)
 505 {
 506         struct active_request_slot *slot = active_queue_head;
 507         struct active_request_slot *newslot;
 508
 509 #ifdef USE_CURL_MULTI
 510         int num_transfers;
 511
 512         /* Wait for a slot to open up if the queue is full */
 513         while (active_requests >= max_requests) {
 514                 curl_multi_perform(curlm, &num_transfers);
 515                 if (num_transfers < active_requests)
 516                         process_curl_messages();
 517         }
 518 #endif
 519
 520         while (slot != NULL && slot->in_use)
 521                 slot = slot->next;
 522
 523         if (slot == NULL) {
 524                 newslot = xmalloc(sizeof(*newslot));
 525                 newslot->curl = NULL;
 526                 newslot->in_use = 0;
 527                 newslot->next = NULL;
 528
 529                 slot = active_queue_head;
 530                 if (slot == NULL) {
 531                         active_queue_head = newslot;
 532                 } else {
 533                         while (slot->next != NULL)
 534                                 slot = slot->next;
 535                         slot->next = newslot;
 536                 }
 537                 slot = newslot;
 538         }
 539
 540         if (slot->curl == NULL) {
 541 #ifdef NO_CURL_EASY_DUPHANDLE
 542                 slot->curl = get_curl_handle();
 543 #else
 544                 slot->curl = curl_easy_duphandle(curl_default);
 545 #endif
 546                 curl_session_count++;
 547         }
 548
 549         active_requests++;
 550         slot->in_use = 1;
 551         slot->local = NULL;
 552         slot->results = NULL;
 553         slot->finished = NULL;
 554         slot->callback_data = NULL;
 555         slot->callback_func = NULL;
 556         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
 557         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
 558         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
 559         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
 560         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
 561         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
 562         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
 563         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 564
 565         return slot;
 566 }
 567
 568 int start_active_slot(struct active_request_slot *slot)
 569 {
 570 #ifdef USE_CURL_MULTI
 571         CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
 572         int num_transfers;
 573
 574         if (curlm_result != CURLM_OK &&
 575             curlm_result != CURLM_CALL_MULTI_PERFORM) {
 576                 active_requests--;
 577                 slot->in_use = 0;
 578                 return 0;
 579         }
 580
 581         /*
 582          * We know there must be something to do, since we just added
 583          * something.
 584          */
 585         curl_multi_perform(curlm, &num_transfers);
 586 #endif
 587         return 1;
 588 }
 589
 590 #ifdef USE_CURL_MULTI
 591 struct fill_chain {
 592         void *data;
 593         int (*fill)(void *);
 594         struct fill_chain *next;
 595 };
 596
 597 static struct fill_chain *fill_cfg;
 598
 599 void add_fill_function(void *data, int (*fill)(void *))
 600 {
 601         struct fill_chain *new = xmalloc(sizeof(*new));
 602         struct fill_chain **linkp = &fill_cfg;
 603         new->data = data;
 604         new->fill = fill;
 605         new->next = NULL;
 606         while (*linkp)
 607                 linkp = &(*linkp)->next;
 608         *linkp = new;
 609 }
 610
 611 void fill_active_slots(void)
 612 {
 613         struct active_request_slot *slot = active_queue_head;
 614
 615         while (active_requests < max_requests) {
 616                 struct fill_chain *fill;
 617                 for (fill = fill_cfg; fill; fill = fill->next)
 618                         if (fill->fill(fill->data))
 619                                 break;
 620
 621                 if (!fill)
 622                         break;
 623         }
 624
 625         while (slot != NULL) {
 626                 if (!slot->in_use && slot->curl != NULL
 627                         && curl_session_count > min_curl_sessions) {
 628                         curl_easy_cleanup(slot->curl);
 629                         slot->curl = NULL;
 630                         curl_session_count--;
 631                 }
 632                 slot = slot->next;
 633         }
 634 }
 635
 636 void step_active_slots(void)
 637 {
 638         int num_transfers;
 639         CURLMcode curlm_result;
 640
 641         do {
 642                 curlm_result = curl_multi_perform(curlm, &num_transfers);
 643         } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
 644         if (num_transfers < active_requests) {
 645                 process_curl_messages();
 646                 fill_active_slots();
 647         }
 648 }
 649 #endif
 650
 651 void run_active_slot(struct active_request_slot *slot)
 652 {
 653 #ifdef USE_CURL_MULTI
 654         long last_pos = 0;
 655         long current_pos;
 656         fd_set readfds;
 657         fd_set writefds;
 658         fd_set excfds;
 659         int max_fd;
 660         struct timeval select_timeout;
 661         int finished = 0;
 662
 663         slot->finished = &finished;
 664         while (!finished) {
 665                 data_received = 0;
 666                 step_active_slots();
 667
 668                 if (!data_received && slot->local != NULL) {
 669                         current_pos = ftell(slot->local);
 670                         if (current_pos > last_pos)
 671                                 data_received++;
 672                         last_pos = current_pos;
 673                 }
 674
 675                 if (slot->in_use && !data_received) {
 676                         max_fd = 0;
 677                         FD_ZERO(&readfds);
 678                         FD_ZERO(&writefds);
 679                         FD_ZERO(&excfds);
 680                         select_timeout.tv_sec = 0;
 681                         select_timeout.tv_usec = 50000;
 682                         select(max_fd, &readfds, &writefds,
 683                                &excfds, &select_timeout);
 684                 }
 685         }
 686 #else
 687         while (slot->in_use) {
 688                 slot->curl_result = curl_easy_perform(slot->curl);
 689                 finish_active_slot(slot);
 690         }
 691 #endif
 692 }
 693
 694 static void closedown_active_slot(struct active_request_slot *slot)
 695 {
 696         active_requests--;
 697         slot->in_use = 0;
 698 }
 699
 700 static void release_active_slot(struct active_request_slot *slot)
 701 {
 702         closedown_active_slot(slot);
 703         if (slot->curl && curl_session_count > min_curl_sessions) {
 704 #ifdef USE_CURL_MULTI
 705                 curl_multi_remove_handle(curlm, slot->curl);
 706 #endif
 707                 curl_easy_cleanup(slot->curl);
 708                 slot->curl = NULL;
 709                 curl_session_count--;
 710         }
 711 #ifdef USE_CURL_MULTI
 712         fill_active_slots();
 713 #endif
 714 }
 715
 716 void finish_active_slot(struct active_request_slot *slot)
 717 {
 718         closedown_active_slot(slot);
 719         curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
 720
 721         if (slot->finished != NULL)
 722                 (*slot->finished) = 1;
 723
 724         /* Store slot results so they can be read after the slot is reused */
 725         if (slot->results != NULL) {
 726                 slot->results->curl_result = slot->curl_result;
 727                 slot->results->http_code = slot->http_code;
 728         }
 729
 730         /* Run callback if appropriate */
 731         if (slot->callback_func != NULL)
 732                 slot->callback_func(slot->callback_data);
 733 }
 734
 735 void finish_all_active_slots(void)
 736 {
 737         struct active_request_slot *slot = active_queue_head;
 738
 739         while (slot != NULL)
 740                 if (slot->in_use) {
 741                         run_active_slot(slot);
 742                         slot = active_queue_head;
 743                 } else {
 744                         slot = slot->next;
 745                 }
 746 }
 747
 748 /* Helpers for modifying and creating URLs */
 749 static inline int needs_quote(int ch)
 750 {
 751         if (((ch >= 'A') && (ch <= 'Z'))
 752                         || ((ch >= 'a') && (ch <= 'z'))
 753                         || ((ch >= '0') && (ch <= '9'))
 754                         || (ch == '/')
 755                         || (ch == '-')
 756                         || (ch == '.'))
 757                 return 0;
 758         return 1;
 759 }
 760
 761 static inline int hex(int v)
 762 {
 763         if (v < 10)
 764                 return '0' + v;
 765         else
 766                 return 'A' + v - 10;
 767 }
 768
 769 static char *quote_ref_url(const char *base, const char *ref)
 770 {
 771         struct strbuf buf = STRBUF_INIT;
 772         const char *cp;
 773         int ch;
 774
 775         end_url_with_slash(&buf, base);
 776
 777         for (cp = ref; (ch = *cp) != 0; cp++)
 778                 if (needs_quote(ch))
 779                         strbuf_addf(&buf, "%%%02x", ch);
 780                 else
 781                         strbuf_addch(&buf, *cp);
 782
 783         return strbuf_detach(&buf, NULL);
 784 }
 785
 786 void append_remote_object_url(struct strbuf *buf, const char *url,
 787                               const char *hex,
 788                               int only_two_digit_prefix)
 789 {
 790         end_url_with_slash(buf, url);
 791
 792         strbuf_addf(buf, "objects/%.*s/", 2, hex);
 793         if (!only_two_digit_prefix)
 794                 strbuf_addf(buf, "%s", hex+2);
 795 }
 796
 797 char *get_remote_object_url(const char *url, const char *hex,
 798                             int only_two_digit_prefix)
 799 {
 800         struct strbuf buf = STRBUF_INIT;
 801         append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
 802         return strbuf_detach(&buf, NULL);
 803 }
 804
 805 /* http_request() targets */
 806 #define HTTP_REQUEST_STRBUF     0
 807 #define HTTP_REQUEST_FILE       1
 808
 809 static int http_request(const char *url, void *result, int target, int options)
 810 {
 811         struct active_request_slot *slot;
 812         struct slot_results results;
 813         struct curl_slist *headers = NULL;
 814         struct strbuf buf = STRBUF_INIT;
 815         int ret;
 816
 817         slot = get_active_slot();
 818         slot->results = &results;
 819         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 820
 821         if (result == NULL) {
 822                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
 823         } else {
 824                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
 825                 curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
 826
 827                 if (target == HTTP_REQUEST_FILE) {
 828                         long posn = ftell(result);
 829                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
 830                                          fwrite);
 831                         if (posn > 0) {
 832                                 strbuf_addf(&buf, "Range: bytes=%ld-", posn);
 833                                 headers = curl_slist_append(headers, buf.buf);
 834                                 strbuf_reset(&buf);
 835                         }
 836                         slot->local = result;
 837                 } else
 838                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
 839                                          fwrite_buffer);
 840         }
 841
 842         strbuf_addstr(&buf, "Pragma:");
 843         if (options & HTTP_NO_CACHE)
 844                 strbuf_addstr(&buf, " no-cache");
 845
 846         headers = curl_slist_append(headers, buf.buf);
 847
 848         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
 849         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
 850
 851         if (start_active_slot(slot)) {
 852                 run_active_slot(slot);
 853                 if (results.curl_result == CURLE_OK)
 854                         ret = HTTP_OK;
 855                 else if (missing_target(&results))
 856                         ret = HTTP_MISSING_TARGET;
 857                 else if (results.http_code == 401) {
 858                         if (user_name) {
 859                                 ret = HTTP_NOAUTH;
 860                         } else {
 861                                 /*
 862                                  * git_getpass is needed here because its very likely stdin/stdout are
 863                                  * pipes to our parent process.  So we instead need to use /dev/tty,
 864                                  * but that is non-portable.  Using git_getpass() can at least be stubbed
 865                                  * on other platforms with a different implementation if/when necessary.
 866                                  */
 867                                 user_name = xstrdup(git_getpass("Username: "));
 868                                 init_curl_http_auth(slot->curl);
 869                                 ret = HTTP_REAUTH;
 870                         }
 871                 } else
 872                         ret = HTTP_ERROR;
 873         } else {
 874                 error("Unable to start HTTP request for %s", url);
 875                 ret = HTTP_START_FAILED;
 876         }
 877
 878         slot->local = NULL;
 879         curl_slist_free_all(headers);
 880         strbuf_release(&buf);
 881
 882         return ret;
 883 }
 884
 885 int http_get_strbuf(const char *url, struct strbuf *result, int options)
 886 {
 887         int http_ret = http_request(url, result, HTTP_REQUEST_STRBUF, options);
 888         if (http_ret == HTTP_REAUTH) {
 889                 http_ret = http_request(url, result, HTTP_REQUEST_STRBUF, options);
 890         }
 891         return http_ret;
 892 }
 893
 894 /*
 895  * Downloads an url and stores the result in the given file.
 896  *
 897  * If a previous interrupted download is detected (i.e. a previous temporary
 898  * file is still around) the download is resumed.
 899  */
 900 static int http_get_file(const char *url, const char *filename, int options)
 901 {
 902         int ret;
 903         struct strbuf tmpfile = STRBUF_INIT;
 904         FILE *result;
 905
 906         strbuf_addf(&tmpfile, "%s.temp", filename);
 907         result = fopen(tmpfile.buf, "a");
 908         if (! result) {
 909                 error("Unable to open local file %s", tmpfile.buf);
 910                 ret = HTTP_ERROR;
 911                 goto cleanup;
 912         }
 913
 914         ret = http_request(url, result, HTTP_REQUEST_FILE, options);
 915         fclose(result);
 916
 917         if ((ret == HTTP_OK) && move_temp_to_file(tmpfile.buf, filename))
 918                 ret = HTTP_ERROR;
 919 cleanup:
 920         strbuf_release(&tmpfile);
 921         return ret;
 922 }
 923
 924 int http_error(const char *url, int ret)
 925 {
 926         /* http_request has already handled HTTP_START_FAILED. */
 927         if (ret != HTTP_START_FAILED)
 928                 error("%s while accessing %s\n", curl_errorstr, url);
 929
 930         return ret;
 931 }
 932
 933 int http_fetch_ref(const char *base, struct ref *ref)
 934 {
 935         char *url;
 936         struct strbuf buffer = STRBUF_INIT;
 937         int ret = -1;
 938
 939         url = quote_ref_url(base, ref->name);
 940         if (http_get_strbuf(url, &buffer, HTTP_NO_CACHE) == HTTP_OK) {
 941                 strbuf_rtrim(&buffer);
 942                 if (buffer.len == 40)
 943                         ret = get_sha1_hex(buffer.buf, ref->old_sha1);
 944                 else if (!prefixcmp(buffer.buf, "ref: ")) {
 945                         ref->symref = xstrdup(buffer.buf + 5);
 946                         ret = 0;
 947                 }
 948         }
 949
 950         strbuf_release(&buffer);
 951         free(url);
 952         return ret;
 953 }
 954
 955 /* Helpers for fetching packs */
 956 static char *fetch_pack_index(unsigned char *sha1, const char *base_url)
 957 {
 958         char *url, *tmp;
 959         struct strbuf buf = STRBUF_INIT;
 960
 961         if (http_is_verbose)
 962                 fprintf(stderr, "Getting index for pack %s\n", sha1_to_hex(sha1));
 963
 964         end_url_with_slash(&buf, base_url);
 965         strbuf_addf(&buf, "objects/pack/pack-%s.idx", sha1_to_hex(sha1));
 966         url = strbuf_detach(&buf, NULL);
 967
 968         strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(sha1));
 969         tmp = strbuf_detach(&buf, NULL);
 970
 971         if (http_get_file(url, tmp, 0) != HTTP_OK) {
 972                 error("Unable to get pack index %s\n", url);
 973                 free(tmp);
 974                 tmp = NULL;
 975         }
 976
 977         free(url);
 978         return tmp;
 979 }
 980
 981 static int fetch_and_setup_pack_index(struct packed_git **packs_head,
 982         unsigned char *sha1, const char *base_url)
 983 {
 984         struct packed_git *new_pack;
 985         char *tmp_idx = NULL;
 986         int ret;
 987
 988         if (has_pack_index(sha1)) {
 989                 new_pack = parse_pack_index(sha1, NULL);
 990                 if (!new_pack)
 991                         return -1; /* parse_pack_index() already issued error message */
 992                 goto add_pack;
 993         }
 994
 995         tmp_idx = fetch_pack_index(sha1, base_url);
 996         if (!tmp_idx)
 997                 return -1;
 998
 999         new_pack = parse_pack_index(sha1, tmp_idx);
1000         if (!new_pack) {
1001                 unlink(tmp_idx);
1002                 free(tmp_idx);
1003
1004                 return -1; /* parse_pack_index() already issued error message */
1005         }
1006
1007         ret = verify_pack_index(new_pack);
1008         if (!ret) {
1009                 close_pack_index(new_pack);
1010                 ret = move_temp_to_file(tmp_idx, sha1_pack_index_name(sha1));
1011         }
1012         free(tmp_idx);
1013         if (ret)
1014                 return -1;
1015
1016 add_pack:
1017         new_pack->next = *packs_head;
1018         *packs_head = new_pack;
1019         return 0;
1020 }
1021
1022 int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
1023 {
1024         int ret = 0, i = 0;
1025         char *url, *data;
1026         struct strbuf buf = STRBUF_INIT;
1027         unsigned char sha1[20];
1028
1029         end_url_with_slash(&buf, base_url);
1030         strbuf_addstr(&buf, "objects/info/packs");
1031         url = strbuf_detach(&buf, NULL);
1032
1033         ret = http_get_strbuf(url, &buf, HTTP_NO_CACHE);
1034         if (ret != HTTP_OK)
1035                 goto cleanup;
1036
1037         data = buf.buf;
1038         while (i < buf.len) {
1039                 switch (data[i]) {
1040                 case 'P':
1041                         i++;
1042                         if (i + 52 <= buf.len &&
1043                             !prefixcmp(data + i, " pack-") &&
1044                             !prefixcmp(data + i + 46, ".pack\n")) {
1045                                 get_sha1_hex(data + i + 6, sha1);
1046                                 fetch_and_setup_pack_index(packs_head, sha1,
1047                                                       base_url);
1048                                 i += 51;
1049                                 break;
1050                         }
1051                 default:
1052                         while (i < buf.len && data[i] != '\n')
1053                                 i++;
1054                 }
1055                 i++;
1056         }
1057
1058 cleanup:
1059         free(url);
1060         return ret;
1061 }
1062
1063 void release_http_pack_request(struct http_pack_request *preq)
1064 {
1065         if (preq->packfile != NULL) {
1066                 fclose(preq->packfile);
1067                 preq->packfile = NULL;
1068                 preq->slot->local = NULL;
1069         }
1070         if (preq->range_header != NULL) {
1071                 curl_slist_free_all(preq->range_header);
1072                 preq->range_header = NULL;
1073         }
1074         preq->slot = NULL;
1075         free(preq->url);
1076 }
1077
1078 int finish_http_pack_request(struct http_pack_request *preq)
1079 {
1080         struct packed_git **lst;
1081         struct packed_git *p = preq->target;
1082         char *tmp_idx;
1083         struct child_process ip;
1084         const char *ip_argv[8];
1085
1086         close_pack_index(p);
1087
1088         fclose(preq->packfile);
1089         preq->packfile = NULL;
1090         preq->slot->local = NULL;
1091
1092         lst = preq->lst;
1093         while (*lst != p)
1094                 lst = &((*lst)->next);
1095         *lst = (*lst)->next;
1096
1097         tmp_idx = xstrdup(preq->tmpfile);
1098         strcpy(tmp_idx + strlen(tmp_idx) - strlen(".pack.temp"),
1099                ".idx.temp");
1100
1101         ip_argv[0] = "index-pack";
1102         ip_argv[1] = "-o";
1103         ip_argv[2] = tmp_idx;
1104         ip_argv[3] = preq->tmpfile;
1105         ip_argv[4] = NULL;
1106
1107         memset(&ip, 0, sizeof(ip));
1108         ip.argv = ip_argv;
1109         ip.git_cmd = 1;
1110         ip.no_stdin = 1;
1111         ip.no_stdout = 1;
1112
1113         if (run_command(&ip)) {
1114                 unlink(preq->tmpfile);
1115                 unlink(tmp_idx);
1116                 free(tmp_idx);
1117                 return -1;
1118         }
1119
1120         unlink(sha1_pack_index_name(p->sha1));
1121
1122         if (move_temp_to_file(preq->tmpfile, sha1_pack_name(p->sha1))
1123          || move_temp_to_file(tmp_idx, sha1_pack_index_name(p->sha1))) {
1124                 free(tmp_idx);
1125                 return -1;
1126         }
1127
1128         install_packed_git(p);
1129         free(tmp_idx);
1130         return 0;
1131 }
1132
1133 struct http_pack_request *new_http_pack_request(
1134         struct packed_git *target, const char *base_url)
1135 {
1136         long prev_posn = 0;
1137         char range[RANGE_HEADER_SIZE];
1138         struct strbuf buf = STRBUF_INIT;
1139         struct http_pack_request *preq;
1140
1141         preq = xmalloc(sizeof(*preq));
1142         preq->target = target;
1143         preq->range_header = NULL;
1144
1145         end_url_with_slash(&buf, base_url);
1146         strbuf_addf(&buf, "objects/pack/pack-%s.pack",
1147                 sha1_to_hex(target->sha1));
1148         preq->url = strbuf_detach(&buf, NULL);
1149
1150         snprintf(preq->tmpfile, sizeof(preq->tmpfile), "%s.temp",
1151                 sha1_pack_name(target->sha1));
1152         preq->packfile = fopen(preq->tmpfile, "a");
1153         if (!preq->packfile) {
1154                 error("Unable to open local file %s for pack",
1155                       preq->tmpfile);
1156                 goto abort;
1157         }
1158
1159         preq->slot = get_active_slot();
1160         preq->slot->local = preq->packfile;
1161         curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
1162         curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
1163         curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
1164         curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1165                 no_pragma_header);
1166
1167         /*
1168          * If there is data present from a previous transfer attempt,
1169          * resume where it left off
1170          */
1171         prev_posn = ftell(preq->packfile);
1172         if (prev_posn>0) {
1173                 if (http_is_verbose)
1174                         fprintf(stderr,
1175                                 "Resuming fetch of pack %s at byte %ld\n",
1176                                 sha1_to_hex(target->sha1), prev_posn);
1177                 sprintf(range, "Range: bytes=%ld-", prev_posn);
1178                 preq->range_header = curl_slist_append(NULL, range);
1179                 curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1180                         preq->range_header);
1181         }
1182
1183         return preq;
1184
1185 abort:
1186         free(preq->url);
1187         free(preq);
1188         return NULL;
1189 }
1190
1191 /* Helpers for fetching objects (loose) */
1192 static size_t fwrite_sha1_file(char *ptr, size_t eltsize, size_t nmemb,
1193                                void *data)
1194 {
1195         unsigned char expn[4096];
1196         size_t size = eltsize * nmemb;
1197         int posn = 0;
1198         struct http_object_request *freq =
1199                 (struct http_object_request *)data;
1200         do {
1201                 ssize_t retval = xwrite(freq->localfile,
1202                                         (char *) ptr + posn, size - posn);
1203                 if (retval < 0)
1204                         return posn;
1205                 posn += retval;
1206         } while (posn < size);
1207
1208         freq->stream.avail_in = size;
1209         freq->stream.next_in = (void *)ptr;
1210         do {
1211                 freq->stream.next_out = expn;
1212                 freq->stream.avail_out = sizeof(expn);
1213                 freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
1214                 git_SHA1_Update(&freq->c, expn,
1215                                 sizeof(expn) - freq->stream.avail_out);
1216         } while (freq->stream.avail_in && freq->zret == Z_OK);
1217         data_received++;
1218         return size;
1219 }
1220
1221 struct http_object_request *new_http_object_request(const char *base_url,
1222         unsigned char *sha1)
1223 {
1224         char *hex = sha1_to_hex(sha1);
1225         char *filename;
1226         char prevfile[PATH_MAX];
1227         int prevlocal;
1228         char prev_buf[PREV_BUF_SIZE];
1229         ssize_t prev_read = 0;
1230         long prev_posn = 0;
1231         char range[RANGE_HEADER_SIZE];
1232         struct curl_slist *range_header = NULL;
1233         struct http_object_request *freq;
1234
1235         freq = xmalloc(sizeof(*freq));
1236         hashcpy(freq->sha1, sha1);
1237         freq->localfile = -1;
1238
1239         filename = sha1_file_name(sha1);
1240         snprintf(freq->tmpfile, sizeof(freq->tmpfile),
1241                  "%s.temp", filename);
1242
1243         snprintf(prevfile, sizeof(prevfile), "%s.prev", filename);
1244         unlink_or_warn(prevfile);
1245         rename(freq->tmpfile, prevfile);
1246         unlink_or_warn(freq->tmpfile);
1247
1248         if (freq->localfile != -1)
1249                 error("fd leakage in start: %d", freq->localfile);
1250         freq->localfile = open(freq->tmpfile,
1251                                O_WRONLY | O_CREAT | O_EXCL, 0666);
1252         /*
1253          * This could have failed due to the "lazy directory creation";
1254          * try to mkdir the last path component.
1255          */
1256         if (freq->localfile < 0 && errno == ENOENT) {
1257                 char *dir = strrchr(freq->tmpfile, '/');
1258                 if (dir) {
1259                         *dir = 0;
1260                         mkdir(freq->tmpfile, 0777);
1261                         *dir = '/';
1262                 }
1263                 freq->localfile = open(freq->tmpfile,
1264                                        O_WRONLY | O_CREAT | O_EXCL, 0666);
1265         }
1266
1267         if (freq->localfile < 0) {
1268                 error("Couldn't create temporary file %s: %s",
1269                       freq->tmpfile, strerror(errno));
1270                 goto abort;
1271         }
1272
1273         memset(&freq->stream, 0, sizeof(freq->stream));
1274
1275         git_inflate_init(&freq->stream);
1276
1277         git_SHA1_Init(&freq->c);
1278
1279         freq->url = get_remote_object_url(base_url, hex, 0);
1280
1281         /*
1282          * If a previous temp file is present, process what was already
1283          * fetched.
1284          */
1285         prevlocal = open(prevfile, O_RDONLY);
1286         if (prevlocal != -1) {
1287                 do {
1288                         prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
1289                         if (prev_read>0) {
1290                                 if (fwrite_sha1_file(prev_buf,
1291                                                      1,
1292                                                      prev_read,
1293                                                      freq) == prev_read) {
1294                                         prev_posn += prev_read;
1295                                 } else {
1296                                         prev_read = -1;
1297                                 }
1298                         }
1299                 } while (prev_read > 0);
1300                 close(prevlocal);
1301         }
1302         unlink_or_warn(prevfile);
1303
1304         /*
1305          * Reset inflate/SHA1 if there was an error reading the previous temp
1306          * file; also rewind to the beginning of the local file.
1307          */
1308         if (prev_read == -1) {
1309                 memset(&freq->stream, 0, sizeof(freq->stream));
1310                 git_inflate_init(&freq->stream);
1311                 git_SHA1_Init(&freq->c);
1312                 if (prev_posn>0) {
1313                         prev_posn = 0;
1314                         lseek(freq->localfile, 0, SEEK_SET);
1315                         if (ftruncate(freq->localfile, 0) < 0) {
1316                                 error("Couldn't truncate temporary file %s: %s",
1317                                           freq->tmpfile, strerror(errno));
1318                                 goto abort;
1319                         }
1320                 }
1321         }
1322
1323         freq->slot = get_active_slot();
1324
1325         curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
1326         curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
1327         curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
1328         curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
1329         curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
1330
1331         /*
1332          * If we have successfully processed data from a previous fetch
1333          * attempt, only fetch the data we don't already have.
1334          */
1335         if (prev_posn>0) {
1336                 if (http_is_verbose)
1337                         fprintf(stderr,
1338                                 "Resuming fetch of object %s at byte %ld\n",
1339                                 hex, prev_posn);
1340                 sprintf(range, "Range: bytes=%ld-", prev_posn);
1341                 range_header = curl_slist_append(range_header, range);
1342                 curl_easy_setopt(freq->slot->curl,
1343                                  CURLOPT_HTTPHEADER, range_header);
1344         }
1345
1346         return freq;
1347
1348 abort:
1349         free(filename);
1350         free(freq->url);
1351         free(freq);
1352         return NULL;
1353 }
1354
1355 void process_http_object_request(struct http_object_request *freq)
1356 {
1357         if (freq->slot == NULL)
1358                 return;
1359         freq->curl_result = freq->slot->curl_result;
1360         freq->http_code = freq->slot->http_code;
1361         freq->slot = NULL;
1362 }
1363
1364 int finish_http_object_request(struct http_object_request *freq)
1365 {
1366         struct stat st;
1367
1368         close(freq->localfile);
1369         freq->localfile = -1;
1370
1371         process_http_object_request(freq);
1372
1373         if (freq->http_code == 416) {
1374                 warning("requested range invalid; we may already have all the data.");
1375         } else if (freq->curl_result != CURLE_OK) {
1376                 if (stat(freq->tmpfile, &st) == 0)
1377                         if (st.st_size == 0)
1378                                 unlink_or_warn(freq->tmpfile);
1379                 return -1;
1380         }
1381
1382         git_inflate_end(&freq->stream);
1383         git_SHA1_Final(freq->real_sha1, &freq->c);
1384         if (freq->zret != Z_STREAM_END) {
1385                 unlink_or_warn(freq->tmpfile);
1386                 return -1;
1387         }
1388         if (hashcmp(freq->sha1, freq->real_sha1)) {
1389                 unlink_or_warn(freq->tmpfile);
1390                 return -1;
1391         }
1392         freq->rename =
1393                 move_temp_to_file(freq->tmpfile, sha1_file_name(freq->sha1));
1394
1395         return freq->rename;
1396 }
1397
1398 void abort_http_object_request(struct http_object_request *freq)
1399 {
1400         unlink_or_warn(freq->tmpfile);
1401
1402         release_http_object_request(freq);
1403 }
1404
1405 void release_http_object_request(struct http_object_request *freq)
1406 {
1407         if (freq->localfile != -1) {
1408                 close(freq->localfile);
1409                 freq->localfile = -1;
1410         }
1411         if (freq->url != NULL) {
1412                 free(freq->url);
1413                 freq->url = NULL;
1414         }
1415         if (freq->slot != NULL) {
1416                 freq->slot->callback_func = NULL;
1417                 freq->slot->callback_data = NULL;
1418                 release_active_slot(freq->slot);
1419                 freq->slot = NULL;
1420         }
1421 }