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