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

   1 #include "git-compat-util.h"
   2 #include "http.h"
   3 #include "pack.h"
   4 #include "sideband.h"
   5 #include "run-command.h"
   6 #include "url.h"
   7 #include "urlmatch.h"
   8 #include "credential.h"
   9 #include "version.h"
  10 #include "pkt-line.h"
  11 #include "gettext.h"
  12 #include "transport.h"
  13
  14 #if LIBCURL_VERSION_NUM >= 0x070a08
  15 long int git_curl_ipresolve = CURL_IPRESOLVE_WHATEVER;
  16 #else
  17 long int git_curl_ipresolve;
  18 #endif
  19 int active_requests;
  20 int http_is_verbose;
  21 size_t http_post_buffer = 16 * LARGE_PACKET_MAX;
  22
  23 #if LIBCURL_VERSION_NUM >= 0x070a06
  24 #define LIBCURL_CAN_HANDLE_AUTH_ANY
  25 #endif
  26
  27 static int min_curl_sessions = 1;
  28 static int curl_session_count;
  29 #ifdef USE_CURL_MULTI
  30 static int max_requests = -1;
  31 static CURLM *curlm;
  32 #endif
  33 #ifndef NO_CURL_EASY_DUPHANDLE
  34 static CURL *curl_default;
  35 #endif
  36
  37 #define PREV_BUF_SIZE 4096
  38
  39 char curl_errorstr[CURL_ERROR_SIZE];
  40
  41 static int curl_ssl_verify = -1;
  42 static int curl_ssl_try;
  43 static const char *ssl_cert;
  44 static const char *ssl_cipherlist;
  45 static const char *ssl_version;
  46 static struct {
  47         const char *name;
  48         long ssl_version;
  49 } sslversions[] = {
  50         { "sslv2", CURL_SSLVERSION_SSLv2 },
  51         { "sslv3", CURL_SSLVERSION_SSLv3 },
  52         { "tlsv1", CURL_SSLVERSION_TLSv1 },
  53 #if LIBCURL_VERSION_NUM >= 0x072200
  54         { "tlsv1.0", CURL_SSLVERSION_TLSv1_0 },
  55         { "tlsv1.1", CURL_SSLVERSION_TLSv1_1 },
  56         { "tlsv1.2", CURL_SSLVERSION_TLSv1_2 },
  57 #endif
  58 };
  59 #if LIBCURL_VERSION_NUM >= 0x070903
  60 static const char *ssl_key;
  61 #endif
  62 #if LIBCURL_VERSION_NUM >= 0x070908
  63 static const char *ssl_capath;
  64 #endif
  65 #if LIBCURL_VERSION_NUM >= 0x072c00
  66 static const char *ssl_pinnedkey;
  67 #endif
  68 static const char *ssl_cainfo;
  69 static long curl_low_speed_limit = -1;
  70 static long curl_low_speed_time = -1;
  71 static int curl_ftp_no_epsv;
  72 static const char *curl_http_proxy;
  73 static const char *curl_no_proxy;
  74 static const char *http_proxy_authmethod;
  75 static struct {
  76         const char *name;
  77         long curlauth_param;
  78 } proxy_authmethods[] = {
  79         { "basic", CURLAUTH_BASIC },
  80         { "digest", CURLAUTH_DIGEST },
  81         { "negotiate", CURLAUTH_GSSNEGOTIATE },
  82         { "ntlm", CURLAUTH_NTLM },
  83 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
  84         { "anyauth", CURLAUTH_ANY },
  85 #endif
  86         /*
  87          * CURLAUTH_DIGEST_IE has no corresponding command-line option in
  88          * curl(1) and is not included in CURLAUTH_ANY, so we leave it out
  89          * here, too
  90          */
  91 };
  92 static struct credential proxy_auth = CREDENTIAL_INIT;
  93 static const char *curl_proxyuserpwd;
  94 static const char *curl_cookie_file;
  95 static int curl_save_cookies;
  96 struct credential http_auth = CREDENTIAL_INIT;
  97 static int http_proactive_auth;
  98 static const char *user_agent;
  99 static int curl_empty_auth;
 100
 101 #if LIBCURL_VERSION_NUM >= 0x071700
 102 /* Use CURLOPT_KEYPASSWD as is */
 103 #elif LIBCURL_VERSION_NUM >= 0x070903
 104 #define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
 105 #else
 106 #define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
 107 #endif
 108
 109 static struct credential cert_auth = CREDENTIAL_INIT;
 110 static int ssl_cert_password_required;
 111 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 112 static unsigned long http_auth_methods = CURLAUTH_ANY;
 113 #endif
 114
 115 static struct curl_slist *pragma_header;
 116 static struct curl_slist *no_pragma_header;
 117
 118 static struct active_request_slot *active_queue_head;
 119
 120 static char *cached_accept_language;
 121
 122 size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
 123 {
 124         size_t size = eltsize * nmemb;
 125         struct buffer *buffer = buffer_;
 126
 127         if (size > buffer->buf.len - buffer->posn)
 128                 size = buffer->buf.len - buffer->posn;
 129         memcpy(ptr, buffer->buf.buf + buffer->posn, size);
 130         buffer->posn += size;
 131
 132         return size;
 133 }
 134
 135 #ifndef NO_CURL_IOCTL
 136 curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
 137 {
 138         struct buffer *buffer = clientp;
 139
 140         switch (cmd) {
 141         case CURLIOCMD_NOP:
 142                 return CURLIOE_OK;
 143
 144         case CURLIOCMD_RESTARTREAD:
 145                 buffer->posn = 0;
 146                 return CURLIOE_OK;
 147
 148         default:
 149                 return CURLIOE_UNKNOWNCMD;
 150         }
 151 }
 152 #endif
 153
 154 size_t fwrite_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
 155 {
 156         size_t size = eltsize * nmemb;
 157         struct strbuf *buffer = buffer_;
 158
 159         strbuf_add(buffer, ptr, size);
 160         return size;
 161 }
 162
 163 size_t fwrite_null(char *ptr, size_t eltsize, size_t nmemb, void *strbuf)
 164 {
 165         return eltsize * nmemb;
 166 }
 167
 168 static void closedown_active_slot(struct active_request_slot *slot)
 169 {
 170         active_requests--;
 171         slot->in_use = 0;
 172 }
 173
 174 static void finish_active_slot(struct active_request_slot *slot)
 175 {
 176         closedown_active_slot(slot);
 177         curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
 178
 179         if (slot->finished != NULL)
 180                 (*slot->finished) = 1;
 181
 182         /* Store slot results so they can be read after the slot is reused */
 183         if (slot->results != NULL) {
 184                 slot->results->curl_result = slot->curl_result;
 185                 slot->results->http_code = slot->http_code;
 186 #if LIBCURL_VERSION_NUM >= 0x070a08
 187                 curl_easy_getinfo(slot->curl, CURLINFO_HTTPAUTH_AVAIL,
 188                                   &slot->results->auth_avail);
 189 #else
 190                 slot->results->auth_avail = 0;
 191 #endif
 192
 193                 curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CONNECTCODE,
 194                         &slot->results->http_connectcode);
 195         }
 196
 197         /* Run callback if appropriate */
 198         if (slot->callback_func != NULL)
 199                 slot->callback_func(slot->callback_data);
 200 }
 201
 202 #ifdef USE_CURL_MULTI
 203 static void process_curl_messages(void)
 204 {
 205         int num_messages;
 206         struct active_request_slot *slot;
 207         CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
 208
 209         while (curl_message != NULL) {
 210                 if (curl_message->msg == CURLMSG_DONE) {
 211                         int curl_result = curl_message->data.result;
 212                         slot = active_queue_head;
 213                         while (slot != NULL &&
 214                                slot->curl != curl_message->easy_handle)
 215                                 slot = slot->next;
 216                         if (slot != NULL) {
 217                                 curl_multi_remove_handle(curlm, slot->curl);
 218                                 slot->curl_result = curl_result;
 219                                 finish_active_slot(slot);
 220                         } else {
 221                                 fprintf(stderr, "Received DONE message for unknown request!\n");
 222                         }
 223                 } else {
 224                         fprintf(stderr, "Unknown CURL message received: %d\n",
 225                                 (int)curl_message->msg);
 226                 }
 227                 curl_message = curl_multi_info_read(curlm, &num_messages);
 228         }
 229 }
 230 #endif
 231
 232 static int http_options(const char *var, const char *value, void *cb)
 233 {
 234         if (!strcmp("http.sslverify", var)) {
 235                 curl_ssl_verify = git_config_bool(var, value);
 236                 return 0;
 237         }
 238         if (!strcmp("http.sslcipherlist", var))
 239                 return git_config_string(&ssl_cipherlist, var, value);
 240         if (!strcmp("http.sslversion", var))
 241                 return git_config_string(&ssl_version, var, value);
 242         if (!strcmp("http.sslcert", var))
 243                 return git_config_string(&ssl_cert, var, value);
 244 #if LIBCURL_VERSION_NUM >= 0x070903
 245         if (!strcmp("http.sslkey", var))
 246                 return git_config_string(&ssl_key, var, value);
 247 #endif
 248 #if LIBCURL_VERSION_NUM >= 0x070908
 249         if (!strcmp("http.sslcapath", var))
 250                 return git_config_pathname(&ssl_capath, var, value);
 251 #endif
 252         if (!strcmp("http.sslcainfo", var))
 253                 return git_config_pathname(&ssl_cainfo, var, value);
 254         if (!strcmp("http.sslcertpasswordprotected", var)) {
 255                 ssl_cert_password_required = git_config_bool(var, value);
 256                 return 0;
 257         }
 258         if (!strcmp("http.ssltry", var)) {
 259                 curl_ssl_try = git_config_bool(var, value);
 260                 return 0;
 261         }
 262         if (!strcmp("http.minsessions", var)) {
 263                 min_curl_sessions = git_config_int(var, value);
 264 #ifndef USE_CURL_MULTI
 265                 if (min_curl_sessions > 1)
 266                         min_curl_sessions = 1;
 267 #endif
 268                 return 0;
 269         }
 270 #ifdef USE_CURL_MULTI
 271         if (!strcmp("http.maxrequests", var)) {
 272                 max_requests = git_config_int(var, value);
 273                 return 0;
 274         }
 275 #endif
 276         if (!strcmp("http.lowspeedlimit", var)) {
 277                 curl_low_speed_limit = (long)git_config_int(var, value);
 278                 return 0;
 279         }
 280         if (!strcmp("http.lowspeedtime", var)) {
 281                 curl_low_speed_time = (long)git_config_int(var, value);
 282                 return 0;
 283         }
 284
 285         if (!strcmp("http.noepsv", var)) {
 286                 curl_ftp_no_epsv = git_config_bool(var, value);
 287                 return 0;
 288         }
 289         if (!strcmp("http.proxy", var))
 290                 return git_config_string(&curl_http_proxy, var, value);
 291
 292         if (!strcmp("http.proxyauthmethod", var))
 293                 return git_config_string(&http_proxy_authmethod, var, value);
 294
 295         if (!strcmp("http.cookiefile", var))
 296                 return git_config_string(&curl_cookie_file, var, value);
 297         if (!strcmp("http.savecookies", var)) {
 298                 curl_save_cookies = git_config_bool(var, value);
 299                 return 0;
 300         }
 301
 302         if (!strcmp("http.postbuffer", var)) {
 303                 http_post_buffer = git_config_int(var, value);
 304                 if (http_post_buffer < LARGE_PACKET_MAX)
 305                         http_post_buffer = LARGE_PACKET_MAX;
 306                 return 0;
 307         }
 308
 309         if (!strcmp("http.useragent", var))
 310                 return git_config_string(&user_agent, var, value);
 311
 312         if (!strcmp("http.emptyauth", var)) {
 313                 curl_empty_auth = git_config_bool(var, value);
 314                 return 0;
 315         }
 316
 317         if (!strcmp("http.pinnedpubkey", var)) {
 318 #if LIBCURL_VERSION_NUM >= 0x072c00
 319                 return git_config_pathname(&ssl_pinnedkey, var, value);
 320 #else
 321                 warning(_("Public key pinning not supported with cURL < 7.44.0"));
 322                 return 0;
 323 #endif
 324         }
 325
 326         /* Fall back on the default ones */
 327         return git_default_config(var, value, cb);
 328 }
 329
 330 static void init_curl_http_auth(CURL *result)
 331 {
 332         if (!http_auth.username) {
 333                 if (curl_empty_auth)
 334                         curl_easy_setopt(result, CURLOPT_USERPWD, ":");
 335                 return;
 336         }
 337
 338         credential_fill(&http_auth);
 339
 340 #if LIBCURL_VERSION_NUM >= 0x071301
 341         curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username);
 342         curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password);
 343 #else
 344         {
 345                 static struct strbuf up = STRBUF_INIT;
 346                 /*
 347                  * Note that we assume we only ever have a single set of
 348                  * credentials in a given program run, so we do not have
 349                  * to worry about updating this buffer, only setting its
 350                  * initial value.
 351                  */
 352                 if (!up.len)
 353                         strbuf_addf(&up, "%s:%s",
 354                                 http_auth.username, http_auth.password);
 355                 curl_easy_setopt(result, CURLOPT_USERPWD, up.buf);
 356         }
 357 #endif
 358 }
 359
 360 /* *var must be free-able */
 361 static void var_override(const char **var, char *value)
 362 {
 363         if (value) {
 364                 free((void *)*var);
 365                 *var = xstrdup(value);
 366         }
 367 }
 368
 369 static void set_proxyauth_name_password(CURL *result)
 370 {
 371 #if LIBCURL_VERSION_NUM >= 0x071301
 372                 curl_easy_setopt(result, CURLOPT_PROXYUSERNAME,
 373                         proxy_auth.username);
 374                 curl_easy_setopt(result, CURLOPT_PROXYPASSWORD,
 375                         proxy_auth.password);
 376 #else
 377                 struct strbuf s = STRBUF_INIT;
 378
 379                 strbuf_addstr_urlencode(&s, proxy_auth.username, 1);
 380                 strbuf_addch(&s, ':');
 381                 strbuf_addstr_urlencode(&s, proxy_auth.password, 1);
 382                 curl_proxyuserpwd = strbuf_detach(&s, NULL);
 383                 curl_easy_setopt(result, CURLOPT_PROXYUSERPWD, curl_proxyuserpwd);
 384 #endif
 385 }
 386
 387 static void init_curl_proxy_auth(CURL *result)
 388 {
 389         if (proxy_auth.username) {
 390                 if (!proxy_auth.password)
 391                         credential_fill(&proxy_auth);
 392                 set_proxyauth_name_password(result);
 393         }
 394
 395         var_override(&http_proxy_authmethod, getenv("GIT_HTTP_PROXY_AUTHMETHOD"));
 396
 397 #if LIBCURL_VERSION_NUM >= 0x070a07 /* CURLOPT_PROXYAUTH and CURLAUTH_ANY */
 398         if (http_proxy_authmethod) {
 399                 int i;
 400                 for (i = 0; i < ARRAY_SIZE(proxy_authmethods); i++) {
 401                         if (!strcmp(http_proxy_authmethod, proxy_authmethods[i].name)) {
 402                                 curl_easy_setopt(result, CURLOPT_PROXYAUTH,
 403                                                 proxy_authmethods[i].curlauth_param);
 404                                 break;
 405                         }
 406                 }
 407                 if (i == ARRAY_SIZE(proxy_authmethods)) {
 408                         warning("unsupported proxy authentication method %s: using anyauth",
 409                                         http_proxy_authmethod);
 410                         curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 411                 }
 412         }
 413         else
 414                 curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 415 #endif
 416 }
 417
 418 static int has_cert_password(void)
 419 {
 420         if (ssl_cert == NULL || ssl_cert_password_required != 1)
 421                 return 0;
 422         if (!cert_auth.password) {
 423                 cert_auth.protocol = xstrdup("cert");
 424                 cert_auth.username = xstrdup("");
 425                 cert_auth.path = xstrdup(ssl_cert);
 426                 credential_fill(&cert_auth);
 427         }
 428         return 1;
 429 }
 430
 431 #if LIBCURL_VERSION_NUM >= 0x071900
 432 static void set_curl_keepalive(CURL *c)
 433 {
 434         curl_easy_setopt(c, CURLOPT_TCP_KEEPALIVE, 1);
 435 }
 436
 437 #elif LIBCURL_VERSION_NUM >= 0x071000
 438 static int sockopt_callback(void *client, curl_socket_t fd, curlsocktype type)
 439 {
 440         int ka = 1;
 441         int rc;
 442         socklen_t len = (socklen_t)sizeof(ka);
 443
 444         if (type != CURLSOCKTYPE_IPCXN)
 445                 return 0;
 446
 447         rc = setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&ka, len);
 448         if (rc < 0)
 449                 warning_errno("unable to set SO_KEEPALIVE on socket");
 450
 451         return 0; /* CURL_SOCKOPT_OK only exists since curl 7.21.5 */
 452 }
 453
 454 static void set_curl_keepalive(CURL *c)
 455 {
 456         curl_easy_setopt(c, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
 457 }
 458
 459 #else
 460 static void set_curl_keepalive(CURL *c)
 461 {
 462         /* not supported on older curl versions */
 463 }
 464 #endif
 465
 466 static CURL *get_curl_handle(void)
 467 {
 468         CURL *result = curl_easy_init();
 469         long allowed_protocols = 0;
 470
 471         if (!result)
 472                 die("curl_easy_init failed");
 473
 474         if (!curl_ssl_verify) {
 475                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
 476                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
 477         } else {
 478                 /* Verify authenticity of the peer's certificate */
 479                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
 480                 /* The name in the cert must match whom we tried to connect */
 481                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
 482         }
 483
 484 #if LIBCURL_VERSION_NUM >= 0x070907
 485         curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
 486 #endif
 487 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 488         curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 489 #endif
 490
 491         if (http_proactive_auth)
 492                 init_curl_http_auth(result);
 493
 494         if (getenv("GIT_SSL_VERSION"))
 495                 ssl_version = getenv("GIT_SSL_VERSION");
 496         if (ssl_version && *ssl_version) {
 497                 int i;
 498                 for (i = 0; i < ARRAY_SIZE(sslversions); i++) {
 499                         if (!strcmp(ssl_version, sslversions[i].name)) {
 500                                 curl_easy_setopt(result, CURLOPT_SSLVERSION,
 501                                                  sslversions[i].ssl_version);
 502                                 break;
 503                         }
 504                 }
 505                 if (i == ARRAY_SIZE(sslversions))
 506                         warning("unsupported ssl version %s: using default",
 507                                 ssl_version);
 508         }
 509
 510         if (getenv("GIT_SSL_CIPHER_LIST"))
 511                 ssl_cipherlist = getenv("GIT_SSL_CIPHER_LIST");
 512         if (ssl_cipherlist != NULL && *ssl_cipherlist)
 513                 curl_easy_setopt(result, CURLOPT_SSL_CIPHER_LIST,
 514                                 ssl_cipherlist);
 515
 516         if (ssl_cert != NULL)
 517                 curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
 518         if (has_cert_password())
 519                 curl_easy_setopt(result, CURLOPT_KEYPASSWD, cert_auth.password);
 520 #if LIBCURL_VERSION_NUM >= 0x070903
 521         if (ssl_key != NULL)
 522                 curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
 523 #endif
 524 #if LIBCURL_VERSION_NUM >= 0x070908
 525         if (ssl_capath != NULL)
 526                 curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
 527 #endif
 528 #if LIBCURL_VERSION_NUM >= 0x072c00
 529         if (ssl_pinnedkey != NULL)
 530                 curl_easy_setopt(result, CURLOPT_PINNEDPUBLICKEY, ssl_pinnedkey);
 531 #endif
 532         if (ssl_cainfo != NULL)
 533                 curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
 534
 535         if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
 536                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
 537                                  curl_low_speed_limit);
 538                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
 539                                  curl_low_speed_time);
 540         }
 541
 542         curl_easy_setopt(result, CURLOPT_FOLLOWLOCATION, 1);
 543         curl_easy_setopt(result, CURLOPT_MAXREDIRS, 20);
 544 #if LIBCURL_VERSION_NUM >= 0x071301
 545         curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
 546 #elif LIBCURL_VERSION_NUM >= 0x071101
 547         curl_easy_setopt(result, CURLOPT_POST301, 1);
 548 #endif
 549 #if LIBCURL_VERSION_NUM >= 0x071304
 550         if (is_transport_allowed("http"))
 551                 allowed_protocols |= CURLPROTO_HTTP;
 552         if (is_transport_allowed("https"))
 553                 allowed_protocols |= CURLPROTO_HTTPS;
 554         if (is_transport_allowed("ftp"))
 555                 allowed_protocols |= CURLPROTO_FTP;
 556         if (is_transport_allowed("ftps"))
 557                 allowed_protocols |= CURLPROTO_FTPS;
 558         curl_easy_setopt(result, CURLOPT_REDIR_PROTOCOLS, allowed_protocols);
 559 #else
 560         if (transport_restrict_protocols())
 561                 warning("protocol restrictions not applied to curl redirects because\n"
 562                         "your curl version is too old (>= 7.19.4)");
 563 #endif
 564
 565         if (getenv("GIT_CURL_VERBOSE"))
 566                 curl_easy_setopt(result, CURLOPT_VERBOSE, 1);
 567
 568         curl_easy_setopt(result, CURLOPT_USERAGENT,
 569                 user_agent ? user_agent : git_user_agent());
 570
 571         if (curl_ftp_no_epsv)
 572                 curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
 573
 574 #ifdef CURLOPT_USE_SSL
 575         if (curl_ssl_try)
 576                 curl_easy_setopt(result, CURLOPT_USE_SSL, CURLUSESSL_TRY);
 577 #endif
 578
 579         /*
 580          * CURL also examines these variables as a fallback; but we need to query
 581          * them here in order to decide whether to prompt for missing password (cf.
 582          * init_curl_proxy_auth()).
 583          *
 584          * Unlike many other common environment variables, these are historically
 585          * lowercase only. It appears that CURL did not know this and implemented
 586          * only uppercase variants, which was later corrected to take both - with
 587          * the exception of http_proxy, which is lowercase only also in CURL. As
 588          * the lowercase versions are the historical quasi-standard, they take
 589          * precedence here, as in CURL.
 590          */
 591         if (!curl_http_proxy) {
 592                 if (!strcmp(http_auth.protocol, "https")) {
 593                         var_override(&curl_http_proxy, getenv("HTTPS_PROXY"));
 594                         var_override(&curl_http_proxy, getenv("https_proxy"));
 595                 } else {
 596                         var_override(&curl_http_proxy, getenv("http_proxy"));
 597                 }
 598                 if (!curl_http_proxy) {
 599                         var_override(&curl_http_proxy, getenv("ALL_PROXY"));
 600                         var_override(&curl_http_proxy, getenv("all_proxy"));
 601                 }
 602         }
 603
 604         if (curl_http_proxy) {
 605                 curl_easy_setopt(result, CURLOPT_PROXY, curl_http_proxy);
 606 #if LIBCURL_VERSION_NUM >= 0x071800
 607                 if (starts_with(curl_http_proxy, "socks5"))
 608                         curl_easy_setopt(result,
 609                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5);
 610                 else if (starts_with(curl_http_proxy, "socks4a"))
 611                         curl_easy_setopt(result,
 612                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4A);
 613                 else if (starts_with(curl_http_proxy, "socks"))
 614                         curl_easy_setopt(result,
 615                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4);
 616 #endif
 617                 if (strstr(curl_http_proxy, "://"))
 618                         credential_from_url(&proxy_auth, curl_http_proxy);
 619                 else {
 620                         struct strbuf url = STRBUF_INIT;
 621                         strbuf_addf(&url, "http://%s", curl_http_proxy);
 622                         credential_from_url(&proxy_auth, url.buf);
 623                         strbuf_release(&url);
 624                 }
 625
 626                 curl_easy_setopt(result, CURLOPT_PROXY, proxy_auth.host);
 627 #if LIBCURL_VERSION_NUM >= 0x071304
 628                 var_override(&curl_no_proxy, getenv("NO_PROXY"));
 629                 var_override(&curl_no_proxy, getenv("no_proxy"));
 630                 curl_easy_setopt(result, CURLOPT_NOPROXY, curl_no_proxy);
 631 #endif
 632         }
 633         init_curl_proxy_auth(result);
 634
 635         set_curl_keepalive(result);
 636
 637         return result;
 638 }
 639
 640 static void set_from_env(const char **var, const char *envname)
 641 {
 642         const char *val = getenv(envname);
 643         if (val)
 644                 *var = val;
 645 }
 646
 647 void http_init(struct remote *remote, const char *url, int proactive_auth)
 648 {
 649         char *low_speed_limit;
 650         char *low_speed_time;
 651         char *normalized_url;
 652         struct urlmatch_config config = { STRING_LIST_INIT_DUP };
 653
 654         config.section = "http";
 655         config.key = NULL;
 656         config.collect_fn = http_options;
 657         config.cascade_fn = git_default_config;
 658         config.cb = NULL;
 659
 660         http_is_verbose = 0;
 661         normalized_url = url_normalize(url, &config.url);
 662
 663         git_config(urlmatch_config_entry, &config);
 664         free(normalized_url);
 665
 666         if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK)
 667                 die("curl_global_init failed");
 668
 669         http_proactive_auth = proactive_auth;
 670
 671         if (remote && remote->http_proxy)
 672                 curl_http_proxy = xstrdup(remote->http_proxy);
 673
 674         if (remote)
 675                 var_override(&http_proxy_authmethod, remote->http_proxy_authmethod);
 676
 677         pragma_header = curl_slist_append(pragma_header, "Pragma: no-cache");
 678         no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
 679
 680 #ifdef USE_CURL_MULTI
 681         {
 682                 char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
 683                 if (http_max_requests != NULL)
 684                         max_requests = atoi(http_max_requests);
 685         }
 686
 687         curlm = curl_multi_init();
 688         if (!curlm)
 689                 die("curl_multi_init failed");
 690 #endif
 691
 692         if (getenv("GIT_SSL_NO_VERIFY"))
 693                 curl_ssl_verify = 0;
 694
 695         set_from_env(&ssl_cert, "GIT_SSL_CERT");
 696 #if LIBCURL_VERSION_NUM >= 0x070903
 697         set_from_env(&ssl_key, "GIT_SSL_KEY");
 698 #endif
 699 #if LIBCURL_VERSION_NUM >= 0x070908
 700         set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
 701 #endif
 702         set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
 703
 704         set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
 705
 706         low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
 707         if (low_speed_limit != NULL)
 708                 curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
 709         low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
 710         if (low_speed_time != NULL)
 711                 curl_low_speed_time = strtol(low_speed_time, NULL, 10);
 712
 713         if (curl_ssl_verify == -1)
 714                 curl_ssl_verify = 1;
 715
 716         curl_session_count = 0;
 717 #ifdef USE_CURL_MULTI
 718         if (max_requests < 1)
 719                 max_requests = DEFAULT_MAX_REQUESTS;
 720 #endif
 721
 722         if (getenv("GIT_CURL_FTP_NO_EPSV"))
 723                 curl_ftp_no_epsv = 1;
 724
 725         if (url) {
 726                 credential_from_url(&http_auth, url);
 727                 if (!ssl_cert_password_required &&
 728                     getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
 729                     starts_with(url, "https://"))
 730                         ssl_cert_password_required = 1;
 731         }
 732
 733 #ifndef NO_CURL_EASY_DUPHANDLE
 734         curl_default = get_curl_handle();
 735 #endif
 736 }
 737
 738 void http_cleanup(void)
 739 {
 740         struct active_request_slot *slot = active_queue_head;
 741
 742         while (slot != NULL) {
 743                 struct active_request_slot *next = slot->next;
 744                 if (slot->curl != NULL) {
 745 #ifdef USE_CURL_MULTI
 746                         curl_multi_remove_handle(curlm, slot->curl);
 747 #endif
 748                         curl_easy_cleanup(slot->curl);
 749                 }
 750                 free(slot);
 751                 slot = next;
 752         }
 753         active_queue_head = NULL;
 754
 755 #ifndef NO_CURL_EASY_DUPHANDLE
 756         curl_easy_cleanup(curl_default);
 757 #endif
 758
 759 #ifdef USE_CURL_MULTI
 760         curl_multi_cleanup(curlm);
 761 #endif
 762         curl_global_cleanup();
 763
 764         curl_slist_free_all(pragma_header);
 765         pragma_header = NULL;
 766
 767         curl_slist_free_all(no_pragma_header);
 768         no_pragma_header = NULL;
 769
 770         if (curl_http_proxy) {
 771                 free((void *)curl_http_proxy);
 772                 curl_http_proxy = NULL;
 773         }
 774
 775         if (proxy_auth.password) {
 776                 memset(proxy_auth.password, 0, strlen(proxy_auth.password));
 777                 free(proxy_auth.password);
 778                 proxy_auth.password = NULL;
 779         }
 780
 781         free((void *)curl_proxyuserpwd);
 782         curl_proxyuserpwd = NULL;
 783
 784         free((void *)http_proxy_authmethod);
 785         http_proxy_authmethod = NULL;
 786
 787         if (cert_auth.password != NULL) {
 788                 memset(cert_auth.password, 0, strlen(cert_auth.password));
 789                 free(cert_auth.password);
 790                 cert_auth.password = NULL;
 791         }
 792         ssl_cert_password_required = 0;
 793
 794         free(cached_accept_language);
 795         cached_accept_language = NULL;
 796 }
 797
 798 struct active_request_slot *get_active_slot(void)
 799 {
 800         struct active_request_slot *slot = active_queue_head;
 801         struct active_request_slot *newslot;
 802
 803 #ifdef USE_CURL_MULTI
 804         int num_transfers;
 805
 806         /* Wait for a slot to open up if the queue is full */
 807         while (active_requests >= max_requests) {
 808                 curl_multi_perform(curlm, &num_transfers);
 809                 if (num_transfers < active_requests)
 810                         process_curl_messages();
 811         }
 812 #endif
 813
 814         while (slot != NULL && slot->in_use)
 815                 slot = slot->next;
 816
 817         if (slot == NULL) {
 818                 newslot = xmalloc(sizeof(*newslot));
 819                 newslot->curl = NULL;
 820                 newslot->in_use = 0;
 821                 newslot->next = NULL;
 822
 823                 slot = active_queue_head;
 824                 if (slot == NULL) {
 825                         active_queue_head = newslot;
 826                 } else {
 827                         while (slot->next != NULL)
 828                                 slot = slot->next;
 829                         slot->next = newslot;
 830                 }
 831                 slot = newslot;
 832         }
 833
 834         if (slot->curl == NULL) {
 835 #ifdef NO_CURL_EASY_DUPHANDLE
 836                 slot->curl = get_curl_handle();
 837 #else
 838                 slot->curl = curl_easy_duphandle(curl_default);
 839 #endif
 840                 curl_session_count++;
 841         }
 842
 843         active_requests++;
 844         slot->in_use = 1;
 845         slot->results = NULL;
 846         slot->finished = NULL;
 847         slot->callback_data = NULL;
 848         slot->callback_func = NULL;
 849         curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
 850         if (curl_save_cookies)
 851                 curl_easy_setopt(slot->curl, CURLOPT_COOKIEJAR, curl_cookie_file);
 852         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
 853         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
 854         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
 855         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
 856         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
 857         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
 858         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
 859         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 860         curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 1);
 861         curl_easy_setopt(slot->curl, CURLOPT_RANGE, NULL);
 862
 863 #if LIBCURL_VERSION_NUM >= 0x070a08
 864         curl_easy_setopt(slot->curl, CURLOPT_IPRESOLVE, git_curl_ipresolve);
 865 #endif
 866 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 867         curl_easy_setopt(slot->curl, CURLOPT_HTTPAUTH, http_auth_methods);
 868 #endif
 869         if (http_auth.password || curl_empty_auth)
 870                 init_curl_http_auth(slot->curl);
 871
 872         return slot;
 873 }
 874
 875 int start_active_slot(struct active_request_slot *slot)
 876 {
 877 #ifdef USE_CURL_MULTI
 878         CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
 879         int num_transfers;
 880
 881         if (curlm_result != CURLM_OK &&
 882             curlm_result != CURLM_CALL_MULTI_PERFORM) {
 883                 active_requests--;
 884                 slot->in_use = 0;
 885                 return 0;
 886         }
 887
 888         /*
 889          * We know there must be something to do, since we just added
 890          * something.
 891          */
 892         curl_multi_perform(curlm, &num_transfers);
 893 #endif
 894         return 1;
 895 }
 896
 897 #ifdef USE_CURL_MULTI
 898 struct fill_chain {
 899         void *data;
 900         int (*fill)(void *);
 901         struct fill_chain *next;
 902 };
 903
 904 static struct fill_chain *fill_cfg;
 905
 906 void add_fill_function(void *data, int (*fill)(void *))
 907 {
 908         struct fill_chain *new = xmalloc(sizeof(*new));
 909         struct fill_chain **linkp = &fill_cfg;
 910         new->data = data;
 911         new->fill = fill;
 912         new->next = NULL;
 913         while (*linkp)
 914                 linkp = &(*linkp)->next;
 915         *linkp = new;
 916 }
 917
 918 void fill_active_slots(void)
 919 {
 920         struct active_request_slot *slot = active_queue_head;
 921
 922         while (active_requests < max_requests) {
 923                 struct fill_chain *fill;
 924                 for (fill = fill_cfg; fill; fill = fill->next)
 925                         if (fill->fill(fill->data))
 926                                 break;
 927
 928                 if (!fill)
 929                         break;
 930         }
 931
 932         while (slot != NULL) {
 933                 if (!slot->in_use && slot->curl != NULL
 934                         && curl_session_count > min_curl_sessions) {
 935                         curl_easy_cleanup(slot->curl);
 936                         slot->curl = NULL;
 937                         curl_session_count--;
 938                 }
 939                 slot = slot->next;
 940         }
 941 }
 942
 943 void step_active_slots(void)
 944 {
 945         int num_transfers;
 946         CURLMcode curlm_result;
 947
 948         do {
 949                 curlm_result = curl_multi_perform(curlm, &num_transfers);
 950         } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
 951         if (num_transfers < active_requests) {
 952                 process_curl_messages();
 953                 fill_active_slots();
 954         }
 955 }
 956 #endif
 957
 958 void run_active_slot(struct active_request_slot *slot)
 959 {
 960 #ifdef USE_CURL_MULTI
 961         fd_set readfds;
 962         fd_set writefds;
 963         fd_set excfds;
 964         int max_fd;
 965         struct timeval select_timeout;
 966         int finished = 0;
 967
 968         slot->finished = &finished;
 969         while (!finished) {
 970                 step_active_slots();
 971
 972                 if (slot->in_use) {
 973 #if LIBCURL_VERSION_NUM >= 0x070f04
 974                         long curl_timeout;
 975                         curl_multi_timeout(curlm, &curl_timeout);
 976                         if (curl_timeout == 0) {
 977                                 continue;
 978                         } else if (curl_timeout == -1) {
 979                                 select_timeout.tv_sec  = 0;
 980                                 select_timeout.tv_usec = 50000;
 981                         } else {
 982                                 select_timeout.tv_sec  =  curl_timeout / 1000;
 983                                 select_timeout.tv_usec = (curl_timeout % 1000) * 1000;
 984                         }
 985 #else
 986                         select_timeout.tv_sec  = 0;
 987                         select_timeout.tv_usec = 50000;
 988 #endif
 989
 990                         max_fd = -1;
 991                         FD_ZERO(&readfds);
 992                         FD_ZERO(&writefds);
 993                         FD_ZERO(&excfds);
 994                         curl_multi_fdset(curlm, &readfds, &writefds, &excfds, &max_fd);
 995
 996                         /*
 997                          * It can happen that curl_multi_timeout returns a pathologically
 998                          * long timeout when curl_multi_fdset returns no file descriptors
 999                          * to read.  See commit message for more details.
1000                          */
1001                         if (max_fd < 0 &&
1002                             (select_timeout.tv_sec > 0 ||
1003                              select_timeout.tv_usec > 50000)) {
1004                                 select_timeout.tv_sec  = 0;
1005                                 select_timeout.tv_usec = 50000;
1006                         }
1007
1008                         select(max_fd+1, &readfds, &writefds, &excfds, &select_timeout);
1009                 }
1010         }
1011 #else
1012         while (slot->in_use) {
1013                 slot->curl_result = curl_easy_perform(slot->curl);
1014                 finish_active_slot(slot);
1015         }
1016 #endif
1017 }
1018
1019 static void release_active_slot(struct active_request_slot *slot)
1020 {
1021         closedown_active_slot(slot);
1022         if (slot->curl && curl_session_count > min_curl_sessions) {
1023 #ifdef USE_CURL_MULTI
1024                 curl_multi_remove_handle(curlm, slot->curl);
1025 #endif
1026                 curl_easy_cleanup(slot->curl);
1027                 slot->curl = NULL;
1028                 curl_session_count--;
1029         }
1030 #ifdef USE_CURL_MULTI
1031         fill_active_slots();
1032 #endif
1033 }
1034
1035 void finish_all_active_slots(void)
1036 {
1037         struct active_request_slot *slot = active_queue_head;
1038
1039         while (slot != NULL)
1040                 if (slot->in_use) {
1041                         run_active_slot(slot);
1042                         slot = active_queue_head;
1043                 } else {
1044                         slot = slot->next;
1045                 }
1046 }
1047
1048 /* Helpers for modifying and creating URLs */
1049 static inline int needs_quote(int ch)
1050 {
1051         if (((ch >= 'A') && (ch <= 'Z'))
1052                         || ((ch >= 'a') && (ch <= 'z'))
1053                         || ((ch >= '0') && (ch <= '9'))
1054                         || (ch == '/')
1055                         || (ch == '-')
1056                         || (ch == '.'))
1057                 return 0;
1058         return 1;
1059 }
1060
1061 static char *quote_ref_url(const char *base, const char *ref)
1062 {
1063         struct strbuf buf = STRBUF_INIT;
1064         const char *cp;
1065         int ch;
1066
1067         end_url_with_slash(&buf, base);
1068
1069         for (cp = ref; (ch = *cp) != 0; cp++)
1070                 if (needs_quote(ch))
1071                         strbuf_addf(&buf, "%%%02x", ch);
1072                 else
1073                         strbuf_addch(&buf, *cp);
1074
1075         return strbuf_detach(&buf, NULL);
1076 }
1077
1078 void append_remote_object_url(struct strbuf *buf, const char *url,
1079                               const char *hex,
1080                               int only_two_digit_prefix)
1081 {
1082         end_url_with_slash(buf, url);
1083
1084         strbuf_addf(buf, "objects/%.*s/", 2, hex);
1085         if (!only_two_digit_prefix)
1086                 strbuf_addf(buf, "%s", hex+2);
1087 }
1088
1089 char *get_remote_object_url(const char *url, const char *hex,
1090                             int only_two_digit_prefix)
1091 {
1092         struct strbuf buf = STRBUF_INIT;
1093         append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
1094         return strbuf_detach(&buf, NULL);
1095 }
1096
1097 static int handle_curl_result(struct slot_results *results)
1098 {
1099         /*
1100          * If we see a failing http code with CURLE_OK, we have turned off
1101          * FAILONERROR (to keep the server's custom error response), and should
1102          * translate the code into failure here.
1103          */
1104         if (results->curl_result == CURLE_OK &&
1105             results->http_code >= 400) {
1106                 results->curl_result = CURLE_HTTP_RETURNED_ERROR;
1107                 /*
1108                  * Normally curl will already have put the "reason phrase"
1109                  * from the server into curl_errorstr; unfortunately without
1110                  * FAILONERROR it is lost, so we can give only the numeric
1111                  * status code.
1112                  */
1113                 snprintf(curl_errorstr, sizeof(curl_errorstr),
1114                          "The requested URL returned error: %ld",
1115                          results->http_code);
1116         }
1117
1118         if (results->curl_result == CURLE_OK) {
1119                 credential_approve(&http_auth);
1120                 if (proxy_auth.password)
1121                         credential_approve(&proxy_auth);
1122                 return HTTP_OK;
1123         } else if (missing_target(results))
1124                 return HTTP_MISSING_TARGET;
1125         else if (results->http_code == 401) {
1126                 if (http_auth.username && http_auth.password) {
1127                         credential_reject(&http_auth);
1128                         return HTTP_NOAUTH;
1129                 } else {
1130 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
1131                         http_auth_methods &= ~CURLAUTH_GSSNEGOTIATE;
1132 #endif
1133                         return HTTP_REAUTH;
1134                 }
1135         } else {
1136                 if (results->http_connectcode == 407)
1137                         credential_reject(&proxy_auth);
1138 #if LIBCURL_VERSION_NUM >= 0x070c00
1139                 if (!curl_errorstr[0])
1140                         strlcpy(curl_errorstr,
1141                                 curl_easy_strerror(results->curl_result),
1142                                 sizeof(curl_errorstr));
1143 #endif
1144                 return HTTP_ERROR;
1145         }
1146 }
1147
1148 int run_one_slot(struct active_request_slot *slot,
1149                  struct slot_results *results)
1150 {
1151         slot->results = results;
1152         if (!start_active_slot(slot)) {
1153                 snprintf(curl_errorstr, sizeof(curl_errorstr),
1154                          "failed to start HTTP request");
1155                 return HTTP_START_FAILED;
1156         }
1157
1158         run_active_slot(slot);
1159         return handle_curl_result(results);
1160 }
1161
1162 static CURLcode curlinfo_strbuf(CURL *curl, CURLINFO info, struct strbuf *buf)
1163 {
1164         char *ptr;
1165         CURLcode ret;
1166
1167         strbuf_reset(buf);
1168         ret = curl_easy_getinfo(curl, info, &ptr);
1169         if (!ret && ptr)
1170                 strbuf_addstr(buf, ptr);
1171         return ret;
1172 }
1173
1174 /*
1175  * Check for and extract a content-type parameter. "raw"
1176  * should be positioned at the start of the potential
1177  * parameter, with any whitespace already removed.
1178  *
1179  * "name" is the name of the parameter. The value is appended
1180  * to "out".
1181  */
1182 static int extract_param(const char *raw, const char *name,
1183                          struct strbuf *out)
1184 {
1185         size_t len = strlen(name);
1186
1187         if (strncasecmp(raw, name, len))
1188                 return -1;
1189         raw += len;
1190
1191         if (*raw != '=')
1192                 return -1;
1193         raw++;
1194
1195         while (*raw && !isspace(*raw) && *raw != ';')
1196                 strbuf_addch(out, *raw++);
1197         return 0;
1198 }
1199
1200 /*
1201  * Extract a normalized version of the content type, with any
1202  * spaces suppressed, all letters lowercased, and no trailing ";"
1203  * or parameters.
1204  *
1205  * Note that we will silently remove even invalid whitespace. For
1206  * example, "text / plain" is specifically forbidden by RFC 2616,
1207  * but "text/plain" is the only reasonable output, and this keeps
1208  * our code simple.
1209  *
1210  * If the "charset" argument is not NULL, store the value of any
1211  * charset parameter there.
1212  *
1213  * Example:
1214  *   "TEXT/PLAIN; charset=utf-8" -> "text/plain", "utf-8"
1215  *   "text / plain" -> "text/plain"
1216  */
1217 static void extract_content_type(struct strbuf *raw, struct strbuf *type,
1218                                  struct strbuf *charset)
1219 {
1220         const char *p;
1221
1222         strbuf_reset(type);
1223         strbuf_grow(type, raw->len);
1224         for (p = raw->buf; *p; p++) {
1225                 if (isspace(*p))
1226                         continue;
1227                 if (*p == ';') {
1228                         p++;
1229                         break;
1230                 }
1231                 strbuf_addch(type, tolower(*p));
1232         }
1233
1234         if (!charset)
1235                 return;
1236
1237         strbuf_reset(charset);
1238         while (*p) {
1239                 while (isspace(*p) || *p == ';')
1240                         p++;
1241                 if (!extract_param(p, "charset", charset))
1242                         return;
1243                 while (*p && !isspace(*p))
1244                         p++;
1245         }
1246
1247         if (!charset->len && starts_with(type->buf, "text/"))
1248                 strbuf_addstr(charset, "ISO-8859-1");
1249 }
1250
1251 static void write_accept_language(struct strbuf *buf)
1252 {
1253         /*
1254          * MAX_DECIMAL_PLACES must not be larger than 3. If it is larger than
1255          * that, q-value will be smaller than 0.001, the minimum q-value the
1256          * HTTP specification allows. See
1257          * http://tools.ietf.org/html/rfc7231#section-5.3.1 for q-value.
1258          */
1259         const int MAX_DECIMAL_PLACES = 3;
1260         const int MAX_LANGUAGE_TAGS = 1000;
1261         const int MAX_ACCEPT_LANGUAGE_HEADER_SIZE = 4000;
1262         char **language_tags = NULL;
1263         int num_langs = 0;
1264         const char *s = get_preferred_languages();
1265         int i;
1266         struct strbuf tag = STRBUF_INIT;
1267
1268         /* Don't add Accept-Language header if no language is preferred. */
1269         if (!s)
1270                 return;
1271
1272         /*
1273          * Split the colon-separated string of preferred languages into
1274          * language_tags array.
1275          */
1276         do {
1277                 /* collect language tag */
1278                 for (; *s && (isalnum(*s) || *s == '_'); s++)
1279                         strbuf_addch(&tag, *s == '_' ? '-' : *s);
1280
1281                 /* skip .codeset, @modifier and any other unnecessary parts */
1282                 while (*s && *s != ':')
1283                         s++;
1284
1285                 if (tag.len) {
1286                         num_langs++;
1287                         REALLOC_ARRAY(language_tags, num_langs);
1288                         language_tags[num_langs - 1] = strbuf_detach(&tag, NULL);
1289                         if (num_langs >= MAX_LANGUAGE_TAGS - 1) /* -1 for '*' */
1290                                 break;
1291                 }
1292         } while (*s++);
1293
1294         /* write Accept-Language header into buf */
1295         if (num_langs) {
1296                 int last_buf_len = 0;
1297                 int max_q;
1298                 int decimal_places;
1299                 char q_format[32];
1300
1301                 /* add '*' */
1302                 REALLOC_ARRAY(language_tags, num_langs + 1);
1303                 language_tags[num_langs++] = "*"; /* it's OK; this won't be freed */
1304
1305                 /* compute decimal_places */
1306                 for (max_q = 1, decimal_places = 0;
1307                      max_q < num_langs && decimal_places <= MAX_DECIMAL_PLACES;
1308                      decimal_places++, max_q *= 10)
1309                         ;
1310
1311                 xsnprintf(q_format, sizeof(q_format), ";q=0.%%0%dd", decimal_places);
1312
1313                 strbuf_addstr(buf, "Accept-Language: ");
1314
1315                 for (i = 0; i < num_langs; i++) {
1316                         if (i > 0)
1317                                 strbuf_addstr(buf, ", ");
1318
1319                         strbuf_addstr(buf, language_tags[i]);
1320
1321                         if (i > 0)
1322                                 strbuf_addf(buf, q_format, max_q - i);
1323
1324                         if (buf->len > MAX_ACCEPT_LANGUAGE_HEADER_SIZE) {
1325                                 strbuf_remove(buf, last_buf_len, buf->len - last_buf_len);
1326                                 break;
1327                         }
1328
1329                         last_buf_len = buf->len;
1330                 }
1331         }
1332
1333         /* free language tags -- last one is a static '*' */
1334         for (i = 0; i < num_langs - 1; i++)
1335                 free(language_tags[i]);
1336         free(language_tags);
1337 }
1338
1339 /*
1340  * Get an Accept-Language header which indicates user's preferred languages.
1341  *
1342  * Examples:
1343  *   LANGUAGE= -> ""
1344  *   LANGUAGE=ko:en -> "Accept-Language: ko, en; q=0.9, *; q=0.1"
1345  *   LANGUAGE=ko_KR.UTF-8:sr@latin -> "Accept-Language: ko-KR, sr; q=0.9, *; q=0.1"
1346  *   LANGUAGE=ko LANG=en_US.UTF-8 -> "Accept-Language: ko, *; q=0.1"
1347  *   LANGUAGE= LANG=en_US.UTF-8 -> "Accept-Language: en-US, *; q=0.1"
1348  *   LANGUAGE= LANG=C -> ""
1349  */
1350 static const char *get_accept_language(void)
1351 {
1352         if (!cached_accept_language) {
1353                 struct strbuf buf = STRBUF_INIT;
1354                 write_accept_language(&buf);
1355                 if (buf.len > 0)
1356                         cached_accept_language = strbuf_detach(&buf, NULL);
1357         }
1358
1359         return cached_accept_language;
1360 }
1361
1362 static void http_opt_request_remainder(CURL *curl, off_t pos)
1363 {
1364         char buf[128];
1365         xsnprintf(buf, sizeof(buf), "%"PRIuMAX"-", (uintmax_t)pos);
1366         curl_easy_setopt(curl, CURLOPT_RANGE, buf);
1367 }
1368
1369 /* http_request() targets */
1370 #define HTTP_REQUEST_STRBUF     0
1371 #define HTTP_REQUEST_FILE       1
1372
1373 static int http_request(const char *url,
1374                         void *result, int target,
1375                         const struct http_get_options *options)
1376 {
1377         struct active_request_slot *slot;
1378         struct slot_results results;
1379         struct curl_slist *headers = NULL;
1380         struct strbuf buf = STRBUF_INIT;
1381         const char *accept_language;
1382         int ret;
1383
1384         slot = get_active_slot();
1385         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1386
1387         if (result == NULL) {
1388                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
1389         } else {
1390                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
1391                 curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
1392
1393                 if (target == HTTP_REQUEST_FILE) {
1394                         off_t posn = ftello(result);
1395                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1396                                          fwrite);
1397                         if (posn > 0)
1398                                 http_opt_request_remainder(slot->curl, posn);
1399                 } else
1400                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1401                                          fwrite_buffer);
1402         }
1403
1404         accept_language = get_accept_language();
1405
1406         if (accept_language)
1407                 headers = curl_slist_append(headers, accept_language);
1408
1409         strbuf_addstr(&buf, "Pragma:");
1410         if (options && options->no_cache)
1411                 strbuf_addstr(&buf, " no-cache");
1412         if (options && options->keep_error)
1413                 curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
1414
1415         headers = curl_slist_append(headers, buf.buf);
1416
1417         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
1418         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
1419         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "gzip");
1420
1421         ret = run_one_slot(slot, &results);
1422
1423         if (options && options->content_type) {
1424                 struct strbuf raw = STRBUF_INIT;
1425                 curlinfo_strbuf(slot->curl, CURLINFO_CONTENT_TYPE, &raw);
1426                 extract_content_type(&raw, options->content_type,
1427                                      options->charset);
1428                 strbuf_release(&raw);
1429         }
1430
1431         if (options && options->effective_url)
1432                 curlinfo_strbuf(slot->curl, CURLINFO_EFFECTIVE_URL,
1433                                 options->effective_url);
1434
1435         curl_slist_free_all(headers);
1436         strbuf_release(&buf);
1437
1438         return ret;
1439 }
1440
1441 /*
1442  * Update the "base" url to a more appropriate value, as deduced by
1443  * redirects seen when requesting a URL starting with "url".
1444  *
1445  * The "asked" parameter is a URL that we asked curl to access, and must begin
1446  * with "base".
1447  *
1448  * The "got" parameter is the URL that curl reported to us as where we ended
1449  * up.
1450  *
1451  * Returns 1 if we updated the base url, 0 otherwise.
1452  *
1453  * Our basic strategy is to compare "base" and "asked" to find the bits
1454  * specific to our request. We then strip those bits off of "got" to yield the
1455  * new base. So for example, if our base is "http://example.com/foo.git",
1456  * and we ask for "http://example.com/foo.git/info/refs", we might end up
1457  * with "https://other.example.com/foo.git/info/refs". We would want the
1458  * new URL to become "https://other.example.com/foo.git".
1459  *
1460  * Note that this assumes a sane redirect scheme. It's entirely possible
1461  * in the example above to end up at a URL that does not even end in
1462  * "info/refs".  In such a case we simply punt, as there is not much we can
1463  * do (and such a scheme is unlikely to represent a real git repository,
1464  * which means we are likely about to abort anyway).
1465  */
1466 static int update_url_from_redirect(struct strbuf *base,
1467                                     const char *asked,
1468                                     const struct strbuf *got)
1469 {
1470         const char *tail;
1471         size_t tail_len;
1472
1473         if (!strcmp(asked, got->buf))
1474                 return 0;
1475
1476         if (!skip_prefix(asked, base->buf, &tail))
1477                 die("BUG: update_url_from_redirect: %s is not a superset of %s",
1478                     asked, base->buf);
1479
1480         tail_len = strlen(tail);
1481
1482         if (got->len < tail_len ||
1483             strcmp(tail, got->buf + got->len - tail_len))
1484                 return 0; /* insane redirect scheme */
1485
1486         strbuf_reset(base);
1487         strbuf_add(base, got->buf, got->len - tail_len);
1488         return 1;
1489 }
1490
1491 static int http_request_reauth(const char *url,
1492                                void *result, int target,
1493                                struct http_get_options *options)
1494 {
1495         int ret = http_request(url, result, target, options);
1496
1497         if (options && options->effective_url && options->base_url) {
1498                 if (update_url_from_redirect(options->base_url,
1499                                              url, options->effective_url)) {
1500                         credential_from_url(&http_auth, options->base_url->buf);
1501                         url = options->effective_url->buf;
1502                 }
1503         }
1504
1505         if (ret != HTTP_REAUTH)
1506                 return ret;
1507
1508         /*
1509          * If we are using KEEP_ERROR, the previous request may have
1510          * put cruft into our output stream; we should clear it out before
1511          * making our next request. We only know how to do this for
1512          * the strbuf case, but that is enough to satisfy current callers.
1513          */
1514         if (options && options->keep_error) {
1515                 switch (target) {
1516                 case HTTP_REQUEST_STRBUF:
1517                         strbuf_reset(result);
1518                         break;
1519                 default:
1520                         die("BUG: HTTP_KEEP_ERROR is only supported with strbufs");
1521                 }
1522         }
1523
1524         credential_fill(&http_auth);
1525
1526         return http_request(url, result, target, options);
1527 }
1528
1529 int http_get_strbuf(const char *url,
1530                     struct strbuf *result,
1531                     struct http_get_options *options)
1532 {
1533         return http_request_reauth(url, result, HTTP_REQUEST_STRBUF, options);
1534 }
1535
1536 /*
1537  * Downloads a URL and stores the result in the given file.
1538  *
1539  * If a previous interrupted download is detected (i.e. a previous temporary
1540  * file is still around) the download is resumed.
1541  */
1542 static int http_get_file(const char *url, const char *filename,
1543                          struct http_get_options *options)
1544 {
1545         int ret;
1546         struct strbuf tmpfile = STRBUF_INIT;
1547         FILE *result;
1548
1549         strbuf_addf(&tmpfile, "%s.temp", filename);
1550         result = fopen(tmpfile.buf, "a");
1551         if (!result) {
1552                 error("Unable to open local file %s", tmpfile.buf);
1553                 ret = HTTP_ERROR;
1554                 goto cleanup;
1555         }
1556
1557         ret = http_request_reauth(url, result, HTTP_REQUEST_FILE, options);
1558         fclose(result);
1559
1560         if (ret == HTTP_OK && finalize_object_file(tmpfile.buf, filename))
1561                 ret = HTTP_ERROR;
1562 cleanup:
1563         strbuf_release(&tmpfile);
1564         return ret;
1565 }
1566
1567 int http_fetch_ref(const char *base, struct ref *ref)
1568 {
1569         struct http_get_options options = {0};
1570         char *url;
1571         struct strbuf buffer = STRBUF_INIT;
1572         int ret = -1;
1573
1574         options.no_cache = 1;
1575
1576         url = quote_ref_url(base, ref->name);
1577         if (http_get_strbuf(url, &buffer, &options) == HTTP_OK) {
1578                 strbuf_rtrim(&buffer);
1579                 if (buffer.len == 40)
1580                         ret = get_oid_hex(buffer.buf, &ref->old_oid);
1581                 else if (starts_with(buffer.buf, "ref: ")) {
1582                         ref->symref = xstrdup(buffer.buf + 5);
1583                         ret = 0;
1584                 }
1585         }
1586
1587         strbuf_release(&buffer);
1588         free(url);
1589         return ret;
1590 }
1591
1592 /* Helpers for fetching packs */
1593 static char *fetch_pack_index(unsigned char *sha1, const char *base_url)
1594 {
1595         char *url, *tmp;
1596         struct strbuf buf = STRBUF_INIT;
1597
1598         if (http_is_verbose)
1599                 fprintf(stderr, "Getting index for pack %s\n", sha1_to_hex(sha1));
1600
1601         end_url_with_slash(&buf, base_url);
1602         strbuf_addf(&buf, "objects/pack/pack-%s.idx", sha1_to_hex(sha1));
1603         url = strbuf_detach(&buf, NULL);
1604
1605         strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(sha1));
1606         tmp = strbuf_detach(&buf, NULL);
1607
1608         if (http_get_file(url, tmp, NULL) != HTTP_OK) {
1609                 error("Unable to get pack index %s", url);
1610                 free(tmp);
1611                 tmp = NULL;
1612         }
1613
1614         free(url);
1615         return tmp;
1616 }
1617
1618 static int fetch_and_setup_pack_index(struct packed_git **packs_head,
1619         unsigned char *sha1, const char *base_url)
1620 {
1621         struct packed_git *new_pack;
1622         char *tmp_idx = NULL;
1623         int ret;
1624
1625         if (has_pack_index(sha1)) {
1626                 new_pack = parse_pack_index(sha1, sha1_pack_index_name(sha1));
1627                 if (!new_pack)
1628                         return -1; /* parse_pack_index() already issued error message */
1629                 goto add_pack;
1630         }
1631
1632         tmp_idx = fetch_pack_index(sha1, base_url);
1633         if (!tmp_idx)
1634                 return -1;
1635
1636         new_pack = parse_pack_index(sha1, tmp_idx);
1637         if (!new_pack) {
1638                 unlink(tmp_idx);
1639                 free(tmp_idx);
1640
1641                 return -1; /* parse_pack_index() already issued error message */
1642         }
1643
1644         ret = verify_pack_index(new_pack);
1645         if (!ret) {
1646                 close_pack_index(new_pack);
1647                 ret = finalize_object_file(tmp_idx, sha1_pack_index_name(sha1));
1648         }
1649         free(tmp_idx);
1650         if (ret)
1651                 return -1;
1652
1653 add_pack:
1654         new_pack->next = *packs_head;
1655         *packs_head = new_pack;
1656         return 0;
1657 }
1658
1659 int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
1660 {
1661         struct http_get_options options = {0};
1662         int ret = 0, i = 0;
1663         char *url, *data;
1664         struct strbuf buf = STRBUF_INIT;
1665         unsigned char sha1[20];
1666
1667         end_url_with_slash(&buf, base_url);
1668         strbuf_addstr(&buf, "objects/info/packs");
1669         url = strbuf_detach(&buf, NULL);
1670
1671         options.no_cache = 1;
1672         ret = http_get_strbuf(url, &buf, &options);
1673         if (ret != HTTP_OK)
1674                 goto cleanup;
1675
1676         data = buf.buf;
1677         while (i < buf.len) {
1678                 switch (data[i]) {
1679                 case 'P':
1680                         i++;
1681                         if (i + 52 <= buf.len &&
1682                             starts_with(data + i, " pack-") &&
1683                             starts_with(data + i + 46, ".pack\n")) {
1684                                 get_sha1_hex(data + i + 6, sha1);
1685                                 fetch_and_setup_pack_index(packs_head, sha1,
1686                                                       base_url);
1687                                 i += 51;
1688                                 break;
1689                         }
1690                 default:
1691                         while (i < buf.len && data[i] != '\n')
1692                                 i++;
1693                 }
1694                 i++;
1695         }
1696
1697 cleanup:
1698         free(url);
1699         return ret;
1700 }
1701
1702 void release_http_pack_request(struct http_pack_request *preq)
1703 {
1704         if (preq->packfile != NULL) {
1705                 fclose(preq->packfile);
1706                 preq->packfile = NULL;
1707         }
1708         preq->slot = NULL;
1709         free(preq->url);
1710         free(preq);
1711 }
1712
1713 int finish_http_pack_request(struct http_pack_request *preq)
1714 {
1715         struct packed_git **lst;
1716         struct packed_git *p = preq->target;
1717         char *tmp_idx;
1718         size_t len;
1719         struct child_process ip = CHILD_PROCESS_INIT;
1720         const char *ip_argv[8];
1721
1722         close_pack_index(p);
1723
1724         fclose(preq->packfile);
1725         preq->packfile = NULL;
1726
1727         lst = preq->lst;
1728         while (*lst != p)
1729                 lst = &((*lst)->next);
1730         *lst = (*lst)->next;
1731
1732         if (!strip_suffix(preq->tmpfile, ".pack.temp", &len))
1733                 die("BUG: pack tmpfile does not end in .pack.temp?");
1734         tmp_idx = xstrfmt("%.*s.idx.temp", (int)len, preq->tmpfile);
1735
1736         ip_argv[0] = "index-pack";
1737         ip_argv[1] = "-o";
1738         ip_argv[2] = tmp_idx;
1739         ip_argv[3] = preq->tmpfile;
1740         ip_argv[4] = NULL;
1741
1742         ip.argv = ip_argv;
1743         ip.git_cmd = 1;
1744         ip.no_stdin = 1;
1745         ip.no_stdout = 1;
1746
1747         if (run_command(&ip)) {
1748                 unlink(preq->tmpfile);
1749                 unlink(tmp_idx);
1750                 free(tmp_idx);
1751                 return -1;
1752         }
1753
1754         unlink(sha1_pack_index_name(p->sha1));
1755
1756         if (finalize_object_file(preq->tmpfile, sha1_pack_name(p->sha1))
1757          || finalize_object_file(tmp_idx, sha1_pack_index_name(p->sha1))) {
1758                 free(tmp_idx);
1759                 return -1;
1760         }
1761
1762         install_packed_git(p);
1763         free(tmp_idx);
1764         return 0;
1765 }
1766
1767 struct http_pack_request *new_http_pack_request(
1768         struct packed_git *target, const char *base_url)
1769 {
1770         off_t prev_posn = 0;
1771         struct strbuf buf = STRBUF_INIT;
1772         struct http_pack_request *preq;
1773
1774         preq = xcalloc(1, sizeof(*preq));
1775         preq->target = target;
1776
1777         end_url_with_slash(&buf, base_url);
1778         strbuf_addf(&buf, "objects/pack/pack-%s.pack",
1779                 sha1_to_hex(target->sha1));
1780         preq->url = strbuf_detach(&buf, NULL);
1781
1782         snprintf(preq->tmpfile, sizeof(preq->tmpfile), "%s.temp",
1783                 sha1_pack_name(target->sha1));
1784         preq->packfile = fopen(preq->tmpfile, "a");
1785         if (!preq->packfile) {
1786                 error("Unable to open local file %s for pack",
1787                       preq->tmpfile);
1788                 goto abort;
1789         }
1790
1791         preq->slot = get_active_slot();
1792         curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
1793         curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
1794         curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
1795         curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1796                 no_pragma_header);
1797
1798         /*
1799          * If there is data present from a previous transfer attempt,
1800          * resume where it left off
1801          */
1802         prev_posn = ftello(preq->packfile);
1803         if (prev_posn>0) {
1804                 if (http_is_verbose)
1805                         fprintf(stderr,
1806                                 "Resuming fetch of pack %s at byte %"PRIuMAX"\n",
1807                                 sha1_to_hex(target->sha1), (uintmax_t)prev_posn);
1808                 http_opt_request_remainder(preq->slot->curl, prev_posn);
1809         }
1810
1811         return preq;
1812
1813 abort:
1814         free(preq->url);
1815         free(preq);
1816         return NULL;
1817 }
1818
1819 /* Helpers for fetching objects (loose) */
1820 static size_t fwrite_sha1_file(char *ptr, size_t eltsize, size_t nmemb,
1821                                void *data)
1822 {
1823         unsigned char expn[4096];
1824         size_t size = eltsize * nmemb;
1825         int posn = 0;
1826         struct http_object_request *freq =
1827                 (struct http_object_request *)data;
1828         do {
1829                 ssize_t retval = xwrite(freq->localfile,
1830                                         (char *) ptr + posn, size - posn);
1831                 if (retval < 0)
1832                         return posn;
1833                 posn += retval;
1834         } while (posn < size);
1835
1836         freq->stream.avail_in = size;
1837         freq->stream.next_in = (void *)ptr;
1838         do {
1839                 freq->stream.next_out = expn;
1840                 freq->stream.avail_out = sizeof(expn);
1841                 freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
1842                 git_SHA1_Update(&freq->c, expn,
1843                                 sizeof(expn) - freq->stream.avail_out);
1844         } while (freq->stream.avail_in && freq->zret == Z_OK);
1845         return size;
1846 }
1847
1848 struct http_object_request *new_http_object_request(const char *base_url,
1849         unsigned char *sha1)
1850 {
1851         char *hex = sha1_to_hex(sha1);
1852         const char *filename;
1853         char prevfile[PATH_MAX];
1854         int prevlocal;
1855         char prev_buf[PREV_BUF_SIZE];
1856         ssize_t prev_read = 0;
1857         off_t prev_posn = 0;
1858         struct http_object_request *freq;
1859
1860         freq = xcalloc(1, sizeof(*freq));
1861         hashcpy(freq->sha1, sha1);
1862         freq->localfile = -1;
1863
1864         filename = sha1_file_name(sha1);
1865         snprintf(freq->tmpfile, sizeof(freq->tmpfile),
1866                  "%s.temp", filename);
1867
1868         snprintf(prevfile, sizeof(prevfile), "%s.prev", filename);
1869         unlink_or_warn(prevfile);
1870         rename(freq->tmpfile, prevfile);
1871         unlink_or_warn(freq->tmpfile);
1872
1873         if (freq->localfile != -1)
1874                 error("fd leakage in start: %d", freq->localfile);
1875         freq->localfile = open(freq->tmpfile,
1876                                O_WRONLY | O_CREAT | O_EXCL, 0666);
1877         /*
1878          * This could have failed due to the "lazy directory creation";
1879          * try to mkdir the last path component.
1880          */
1881         if (freq->localfile < 0 && errno == ENOENT) {
1882                 char *dir = strrchr(freq->tmpfile, '/');
1883                 if (dir) {
1884                         *dir = 0;
1885                         mkdir(freq->tmpfile, 0777);
1886                         *dir = '/';
1887                 }
1888                 freq->localfile = open(freq->tmpfile,
1889                                        O_WRONLY | O_CREAT | O_EXCL, 0666);
1890         }
1891
1892         if (freq->localfile < 0) {
1893                 error_errno("Couldn't create temporary file %s", freq->tmpfile);
1894                 goto abort;
1895         }
1896
1897         git_inflate_init(&freq->stream);
1898
1899         git_SHA1_Init(&freq->c);
1900
1901         freq->url = get_remote_object_url(base_url, hex, 0);
1902
1903         /*
1904          * If a previous temp file is present, process what was already
1905          * fetched.
1906          */
1907         prevlocal = open(prevfile, O_RDONLY);
1908         if (prevlocal != -1) {
1909                 do {
1910                         prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
1911                         if (prev_read>0) {
1912                                 if (fwrite_sha1_file(prev_buf,
1913                                                      1,
1914                                                      prev_read,
1915                                                      freq) == prev_read) {
1916                                         prev_posn += prev_read;
1917                                 } else {
1918                                         prev_read = -1;
1919                                 }
1920                         }
1921                 } while (prev_read > 0);
1922                 close(prevlocal);
1923         }
1924         unlink_or_warn(prevfile);
1925
1926         /*
1927          * Reset inflate/SHA1 if there was an error reading the previous temp
1928          * file; also rewind to the beginning of the local file.
1929          */
1930         if (prev_read == -1) {
1931                 memset(&freq->stream, 0, sizeof(freq->stream));
1932                 git_inflate_init(&freq->stream);
1933                 git_SHA1_Init(&freq->c);
1934                 if (prev_posn>0) {
1935                         prev_posn = 0;
1936                         lseek(freq->localfile, 0, SEEK_SET);
1937                         if (ftruncate(freq->localfile, 0) < 0) {
1938                                 error_errno("Couldn't truncate temporary file %s",
1939                                             freq->tmpfile);
1940                                 goto abort;
1941                         }
1942                 }
1943         }
1944
1945         freq->slot = get_active_slot();
1946
1947         curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
1948         curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
1949         curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
1950         curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
1951         curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
1952
1953         /*
1954          * If we have successfully processed data from a previous fetch
1955          * attempt, only fetch the data we don't already have.
1956          */
1957         if (prev_posn>0) {
1958                 if (http_is_verbose)
1959                         fprintf(stderr,
1960                                 "Resuming fetch of object %s at byte %"PRIuMAX"\n",
1961                                 hex, (uintmax_t)prev_posn);
1962                 http_opt_request_remainder(freq->slot->curl, prev_posn);
1963         }
1964
1965         return freq;
1966
1967 abort:
1968         free(freq->url);
1969         free(freq);
1970         return NULL;
1971 }
1972
1973 void process_http_object_request(struct http_object_request *freq)
1974 {
1975         if (freq->slot == NULL)
1976                 return;
1977         freq->curl_result = freq->slot->curl_result;
1978         freq->http_code = freq->slot->http_code;
1979         freq->slot = NULL;
1980 }
1981
1982 int finish_http_object_request(struct http_object_request *freq)
1983 {
1984         struct stat st;
1985
1986         close(freq->localfile);
1987         freq->localfile = -1;
1988
1989         process_http_object_request(freq);
1990
1991         if (freq->http_code == 416) {
1992                 warning("requested range invalid; we may already have all the data.");
1993         } else if (freq->curl_result != CURLE_OK) {
1994                 if (stat(freq->tmpfile, &st) == 0)
1995                         if (st.st_size == 0)
1996                                 unlink_or_warn(freq->tmpfile);
1997                 return -1;
1998         }
1999
2000         git_inflate_end(&freq->stream);
2001         git_SHA1_Final(freq->real_sha1, &freq->c);
2002         if (freq->zret != Z_STREAM_END) {
2003                 unlink_or_warn(freq->tmpfile);
2004                 return -1;
2005         }
2006         if (hashcmp(freq->sha1, freq->real_sha1)) {
2007                 unlink_or_warn(freq->tmpfile);
2008                 return -1;
2009         }
2010         freq->rename =
2011                 finalize_object_file(freq->tmpfile, sha1_file_name(freq->sha1));
2012
2013         return freq->rename;
2014 }
2015
2016 void abort_http_object_request(struct http_object_request *freq)
2017 {
2018         unlink_or_warn(freq->tmpfile);
2019
2020         release_http_object_request(freq);
2021 }
2022
2023 void release_http_object_request(struct http_object_request *freq)
2024 {
2025         if (freq->localfile != -1) {
2026                 close(freq->localfile);
2027                 freq->localfile = -1;
2028         }
2029         if (freq->url != NULL) {
2030                 free(freq->url);
2031                 freq->url = NULL;
2032         }
2033         if (freq->slot != NULL) {
2034                 freq->slot->callback_func = NULL;
2035                 freq->slot->callback_data = NULL;
2036                 release_active_slot(freq->slot);
2037                 freq->slot = NULL;
2038         }
2039 }