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 enum http_follow_config http_follow_config = HTTP_FOLLOW_INITIAL;
 102
 103 #if LIBCURL_VERSION_NUM >= 0x071700
 104 /* Use CURLOPT_KEYPASSWD as is */
 105 #elif LIBCURL_VERSION_NUM >= 0x070903
 106 #define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
 107 #else
 108 #define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
 109 #endif
 110
 111 static struct credential cert_auth = CREDENTIAL_INIT;
 112 static int ssl_cert_password_required;
 113 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 114 static unsigned long http_auth_methods = CURLAUTH_ANY;
 115 #endif
 116
 117 static struct curl_slist *pragma_header;
 118 static struct curl_slist *no_pragma_header;
 119 static struct curl_slist *extra_http_headers;
 120
 121 static struct active_request_slot *active_queue_head;
 122
 123 static char *cached_accept_language;
 124
 125 size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
 126 {
 127         size_t size = eltsize * nmemb;
 128         struct buffer *buffer = buffer_;
 129
 130         if (size > buffer->buf.len - buffer->posn)
 131                 size = buffer->buf.len - buffer->posn;
 132         memcpy(ptr, buffer->buf.buf + buffer->posn, size);
 133         buffer->posn += size;
 134
 135         return size;
 136 }
 137
 138 #ifndef NO_CURL_IOCTL
 139 curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
 140 {
 141         struct buffer *buffer = clientp;
 142
 143         switch (cmd) {
 144         case CURLIOCMD_NOP:
 145                 return CURLIOE_OK;
 146
 147         case CURLIOCMD_RESTARTREAD:
 148                 buffer->posn = 0;
 149                 return CURLIOE_OK;
 150
 151         default:
 152                 return CURLIOE_UNKNOWNCMD;
 153         }
 154 }
 155 #endif
 156
 157 size_t fwrite_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
 158 {
 159         size_t size = eltsize * nmemb;
 160         struct strbuf *buffer = buffer_;
 161
 162         strbuf_add(buffer, ptr, size);
 163         return size;
 164 }
 165
 166 size_t fwrite_null(char *ptr, size_t eltsize, size_t nmemb, void *strbuf)
 167 {
 168         return eltsize * nmemb;
 169 }
 170
 171 static void closedown_active_slot(struct active_request_slot *slot)
 172 {
 173         active_requests--;
 174         slot->in_use = 0;
 175 }
 176
 177 static void finish_active_slot(struct active_request_slot *slot)
 178 {
 179         closedown_active_slot(slot);
 180         curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
 181
 182         if (slot->finished != NULL)
 183                 (*slot->finished) = 1;
 184
 185         /* Store slot results so they can be read after the slot is reused */
 186         if (slot->results != NULL) {
 187                 slot->results->curl_result = slot->curl_result;
 188                 slot->results->http_code = slot->http_code;
 189 #if LIBCURL_VERSION_NUM >= 0x070a08
 190                 curl_easy_getinfo(slot->curl, CURLINFO_HTTPAUTH_AVAIL,
 191                                   &slot->results->auth_avail);
 192 #else
 193                 slot->results->auth_avail = 0;
 194 #endif
 195
 196                 curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CONNECTCODE,
 197                         &slot->results->http_connectcode);
 198         }
 199
 200         /* Run callback if appropriate */
 201         if (slot->callback_func != NULL)
 202                 slot->callback_func(slot->callback_data);
 203 }
 204
 205 #ifdef USE_CURL_MULTI
 206 static void process_curl_messages(void)
 207 {
 208         int num_messages;
 209         struct active_request_slot *slot;
 210         CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
 211
 212         while (curl_message != NULL) {
 213                 if (curl_message->msg == CURLMSG_DONE) {
 214                         int curl_result = curl_message->data.result;
 215                         slot = active_queue_head;
 216                         while (slot != NULL &&
 217                                slot->curl != curl_message->easy_handle)
 218                                 slot = slot->next;
 219                         if (slot != NULL) {
 220                                 curl_multi_remove_handle(curlm, slot->curl);
 221                                 slot->curl_result = curl_result;
 222                                 finish_active_slot(slot);
 223                         } else {
 224                                 fprintf(stderr, "Received DONE message for unknown request!\n");
 225                         }
 226                 } else {
 227                         fprintf(stderr, "Unknown CURL message received: %d\n",
 228                                 (int)curl_message->msg);
 229                 }
 230                 curl_message = curl_multi_info_read(curlm, &num_messages);
 231         }
 232 }
 233 #endif
 234
 235 static int http_options(const char *var, const char *value, void *cb)
 236 {
 237         if (!strcmp("http.sslverify", var)) {
 238                 curl_ssl_verify = git_config_bool(var, value);
 239                 return 0;
 240         }
 241         if (!strcmp("http.sslcipherlist", var))
 242                 return git_config_string(&ssl_cipherlist, var, value);
 243         if (!strcmp("http.sslversion", var))
 244                 return git_config_string(&ssl_version, var, value);
 245         if (!strcmp("http.sslcert", var))
 246                 return git_config_string(&ssl_cert, var, value);
 247 #if LIBCURL_VERSION_NUM >= 0x070903
 248         if (!strcmp("http.sslkey", var))
 249                 return git_config_string(&ssl_key, var, value);
 250 #endif
 251 #if LIBCURL_VERSION_NUM >= 0x070908
 252         if (!strcmp("http.sslcapath", var))
 253                 return git_config_pathname(&ssl_capath, var, value);
 254 #endif
 255         if (!strcmp("http.sslcainfo", var))
 256                 return git_config_pathname(&ssl_cainfo, var, value);
 257         if (!strcmp("http.sslcertpasswordprotected", var)) {
 258                 ssl_cert_password_required = git_config_bool(var, value);
 259                 return 0;
 260         }
 261         if (!strcmp("http.ssltry", var)) {
 262                 curl_ssl_try = git_config_bool(var, value);
 263                 return 0;
 264         }
 265         if (!strcmp("http.minsessions", var)) {
 266                 min_curl_sessions = git_config_int(var, value);
 267 #ifndef USE_CURL_MULTI
 268                 if (min_curl_sessions > 1)
 269                         min_curl_sessions = 1;
 270 #endif
 271                 return 0;
 272         }
 273 #ifdef USE_CURL_MULTI
 274         if (!strcmp("http.maxrequests", var)) {
 275                 max_requests = git_config_int(var, value);
 276                 return 0;
 277         }
 278 #endif
 279         if (!strcmp("http.lowspeedlimit", var)) {
 280                 curl_low_speed_limit = (long)git_config_int(var, value);
 281                 return 0;
 282         }
 283         if (!strcmp("http.lowspeedtime", var)) {
 284                 curl_low_speed_time = (long)git_config_int(var, value);
 285                 return 0;
 286         }
 287
 288         if (!strcmp("http.noepsv", var)) {
 289                 curl_ftp_no_epsv = git_config_bool(var, value);
 290                 return 0;
 291         }
 292         if (!strcmp("http.proxy", var))
 293                 return git_config_string(&curl_http_proxy, var, value);
 294
 295         if (!strcmp("http.proxyauthmethod", var))
 296                 return git_config_string(&http_proxy_authmethod, var, value);
 297
 298         if (!strcmp("http.cookiefile", var))
 299                 return git_config_pathname(&curl_cookie_file, var, value);
 300         if (!strcmp("http.savecookies", var)) {
 301                 curl_save_cookies = git_config_bool(var, value);
 302                 return 0;
 303         }
 304
 305         if (!strcmp("http.postbuffer", var)) {
 306                 http_post_buffer = git_config_int(var, value);
 307                 if (http_post_buffer < LARGE_PACKET_MAX)
 308                         http_post_buffer = LARGE_PACKET_MAX;
 309                 return 0;
 310         }
 311
 312         if (!strcmp("http.useragent", var))
 313                 return git_config_string(&user_agent, var, value);
 314
 315         if (!strcmp("http.emptyauth", var)) {
 316                 curl_empty_auth = git_config_bool(var, value);
 317                 return 0;
 318         }
 319
 320         if (!strcmp("http.pinnedpubkey", var)) {
 321 #if LIBCURL_VERSION_NUM >= 0x072c00
 322                 return git_config_pathname(&ssl_pinnedkey, var, value);
 323 #else
 324                 warning(_("Public key pinning not supported with cURL < 7.44.0"));
 325                 return 0;
 326 #endif
 327         }
 328
 329         if (!strcmp("http.extraheader", var)) {
 330                 if (!value) {
 331                         return config_error_nonbool(var);
 332                 } else if (!*value) {
 333                         curl_slist_free_all(extra_http_headers);
 334                         extra_http_headers = NULL;
 335                 } else {
 336                         extra_http_headers =
 337                                 curl_slist_append(extra_http_headers, value);
 338                 }
 339                 return 0;
 340         }
 341
 342         if (!strcmp("http.followredirects", var)) {
 343                 if (value && !strcmp(value, "initial"))
 344                         http_follow_config = HTTP_FOLLOW_INITIAL;
 345                 else if (git_config_bool(var, value))
 346                         http_follow_config = HTTP_FOLLOW_ALWAYS;
 347                 else
 348                         http_follow_config = HTTP_FOLLOW_NONE;
 349                 return 0;
 350         }
 351
 352         /* Fall back on the default ones */
 353         return git_default_config(var, value, cb);
 354 }
 355
 356 static void init_curl_http_auth(CURL *result)
 357 {
 358         if (!http_auth.username) {
 359                 if (curl_empty_auth)
 360                         curl_easy_setopt(result, CURLOPT_USERPWD, ":");
 361                 return;
 362         }
 363
 364         credential_fill(&http_auth);
 365
 366 #if LIBCURL_VERSION_NUM >= 0x071301
 367         curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username);
 368         curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password);
 369 #else
 370         {
 371                 static struct strbuf up = STRBUF_INIT;
 372                 /*
 373                  * Note that we assume we only ever have a single set of
 374                  * credentials in a given program run, so we do not have
 375                  * to worry about updating this buffer, only setting its
 376                  * initial value.
 377                  */
 378                 if (!up.len)
 379                         strbuf_addf(&up, "%s:%s",
 380                                 http_auth.username, http_auth.password);
 381                 curl_easy_setopt(result, CURLOPT_USERPWD, up.buf);
 382         }
 383 #endif
 384 }
 385
 386 /* *var must be free-able */
 387 static void var_override(const char **var, char *value)
 388 {
 389         if (value) {
 390                 free((void *)*var);
 391                 *var = xstrdup(value);
 392         }
 393 }
 394
 395 static void set_proxyauth_name_password(CURL *result)
 396 {
 397 #if LIBCURL_VERSION_NUM >= 0x071301
 398                 curl_easy_setopt(result, CURLOPT_PROXYUSERNAME,
 399                         proxy_auth.username);
 400                 curl_easy_setopt(result, CURLOPT_PROXYPASSWORD,
 401                         proxy_auth.password);
 402 #else
 403                 struct strbuf s = STRBUF_INIT;
 404
 405                 strbuf_addstr_urlencode(&s, proxy_auth.username, 1);
 406                 strbuf_addch(&s, ':');
 407                 strbuf_addstr_urlencode(&s, proxy_auth.password, 1);
 408                 curl_proxyuserpwd = strbuf_detach(&s, NULL);
 409                 curl_easy_setopt(result, CURLOPT_PROXYUSERPWD, curl_proxyuserpwd);
 410 #endif
 411 }
 412
 413 static void init_curl_proxy_auth(CURL *result)
 414 {
 415         if (proxy_auth.username) {
 416                 if (!proxy_auth.password)
 417                         credential_fill(&proxy_auth);
 418                 set_proxyauth_name_password(result);
 419         }
 420
 421         var_override(&http_proxy_authmethod, getenv("GIT_HTTP_PROXY_AUTHMETHOD"));
 422
 423 #if LIBCURL_VERSION_NUM >= 0x070a07 /* CURLOPT_PROXYAUTH and CURLAUTH_ANY */
 424         if (http_proxy_authmethod) {
 425                 int i;
 426                 for (i = 0; i < ARRAY_SIZE(proxy_authmethods); i++) {
 427                         if (!strcmp(http_proxy_authmethod, proxy_authmethods[i].name)) {
 428                                 curl_easy_setopt(result, CURLOPT_PROXYAUTH,
 429                                                 proxy_authmethods[i].curlauth_param);
 430                                 break;
 431                         }
 432                 }
 433                 if (i == ARRAY_SIZE(proxy_authmethods)) {
 434                         warning("unsupported proxy authentication method %s: using anyauth",
 435                                         http_proxy_authmethod);
 436                         curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 437                 }
 438         }
 439         else
 440                 curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 441 #endif
 442 }
 443
 444 static int has_cert_password(void)
 445 {
 446         if (ssl_cert == NULL || ssl_cert_password_required != 1)
 447                 return 0;
 448         if (!cert_auth.password) {
 449                 cert_auth.protocol = xstrdup("cert");
 450                 cert_auth.username = xstrdup("");
 451                 cert_auth.path = xstrdup(ssl_cert);
 452                 credential_fill(&cert_auth);
 453         }
 454         return 1;
 455 }
 456
 457 #if LIBCURL_VERSION_NUM >= 0x071900
 458 static void set_curl_keepalive(CURL *c)
 459 {
 460         curl_easy_setopt(c, CURLOPT_TCP_KEEPALIVE, 1);
 461 }
 462
 463 #elif LIBCURL_VERSION_NUM >= 0x071000
 464 static int sockopt_callback(void *client, curl_socket_t fd, curlsocktype type)
 465 {
 466         int ka = 1;
 467         int rc;
 468         socklen_t len = (socklen_t)sizeof(ka);
 469
 470         if (type != CURLSOCKTYPE_IPCXN)
 471                 return 0;
 472
 473         rc = setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&ka, len);
 474         if (rc < 0)
 475                 warning_errno("unable to set SO_KEEPALIVE on socket");
 476
 477         return 0; /* CURL_SOCKOPT_OK only exists since curl 7.21.5 */
 478 }
 479
 480 static void set_curl_keepalive(CURL *c)
 481 {
 482         curl_easy_setopt(c, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
 483 }
 484
 485 #else
 486 static void set_curl_keepalive(CURL *c)
 487 {
 488         /* not supported on older curl versions */
 489 }
 490 #endif
 491
 492 static CURL *get_curl_handle(void)
 493 {
 494         CURL *result = curl_easy_init();
 495         long allowed_protocols = 0;
 496
 497         if (!result)
 498                 die("curl_easy_init failed");
 499
 500         if (!curl_ssl_verify) {
 501                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
 502                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
 503         } else {
 504                 /* Verify authenticity of the peer's certificate */
 505                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
 506                 /* The name in the cert must match whom we tried to connect */
 507                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
 508         }
 509
 510 #if LIBCURL_VERSION_NUM >= 0x070907
 511         curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
 512 #endif
 513 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 514         curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 515 #endif
 516
 517         if (http_proactive_auth)
 518                 init_curl_http_auth(result);
 519
 520         if (getenv("GIT_SSL_VERSION"))
 521                 ssl_version = getenv("GIT_SSL_VERSION");
 522         if (ssl_version && *ssl_version) {
 523                 int i;
 524                 for (i = 0; i < ARRAY_SIZE(sslversions); i++) {
 525                         if (!strcmp(ssl_version, sslversions[i].name)) {
 526                                 curl_easy_setopt(result, CURLOPT_SSLVERSION,
 527                                                  sslversions[i].ssl_version);
 528                                 break;
 529                         }
 530                 }
 531                 if (i == ARRAY_SIZE(sslversions))
 532                         warning("unsupported ssl version %s: using default",
 533                                 ssl_version);
 534         }
 535
 536         if (getenv("GIT_SSL_CIPHER_LIST"))
 537                 ssl_cipherlist = getenv("GIT_SSL_CIPHER_LIST");
 538         if (ssl_cipherlist != NULL && *ssl_cipherlist)
 539                 curl_easy_setopt(result, CURLOPT_SSL_CIPHER_LIST,
 540                                 ssl_cipherlist);
 541
 542         if (ssl_cert != NULL)
 543                 curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
 544         if (has_cert_password())
 545                 curl_easy_setopt(result, CURLOPT_KEYPASSWD, cert_auth.password);
 546 #if LIBCURL_VERSION_NUM >= 0x070903
 547         if (ssl_key != NULL)
 548                 curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
 549 #endif
 550 #if LIBCURL_VERSION_NUM >= 0x070908
 551         if (ssl_capath != NULL)
 552                 curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
 553 #endif
 554 #if LIBCURL_VERSION_NUM >= 0x072c00
 555         if (ssl_pinnedkey != NULL)
 556                 curl_easy_setopt(result, CURLOPT_PINNEDPUBLICKEY, ssl_pinnedkey);
 557 #endif
 558         if (ssl_cainfo != NULL)
 559                 curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
 560
 561         if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
 562                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
 563                                  curl_low_speed_limit);
 564                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
 565                                  curl_low_speed_time);
 566         }
 567
 568         curl_easy_setopt(result, CURLOPT_MAXREDIRS, 20);
 569 #if LIBCURL_VERSION_NUM >= 0x071301
 570         curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
 571 #elif LIBCURL_VERSION_NUM >= 0x071101
 572         curl_easy_setopt(result, CURLOPT_POST301, 1);
 573 #endif
 574 #if LIBCURL_VERSION_NUM >= 0x071304
 575         if (is_transport_allowed("http"))
 576                 allowed_protocols |= CURLPROTO_HTTP;
 577         if (is_transport_allowed("https"))
 578                 allowed_protocols |= CURLPROTO_HTTPS;
 579         if (is_transport_allowed("ftp"))
 580                 allowed_protocols |= CURLPROTO_FTP;
 581         if (is_transport_allowed("ftps"))
 582                 allowed_protocols |= CURLPROTO_FTPS;
 583         curl_easy_setopt(result, CURLOPT_REDIR_PROTOCOLS, allowed_protocols);
 584         curl_easy_setopt(result, CURLOPT_PROTOCOLS, allowed_protocols);
 585 #else
 586         if (transport_restrict_protocols())
 587                 warning("protocol restrictions not applied to curl redirects because\n"
 588                         "your curl version is too old (>= 7.19.4)");
 589 #endif
 590
 591         if (getenv("GIT_CURL_VERBOSE"))
 592                 curl_easy_setopt(result, CURLOPT_VERBOSE, 1);
 593
 594         curl_easy_setopt(result, CURLOPT_USERAGENT,
 595                 user_agent ? user_agent : git_user_agent());
 596
 597         if (curl_ftp_no_epsv)
 598                 curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
 599
 600 #ifdef CURLOPT_USE_SSL
 601         if (curl_ssl_try)
 602                 curl_easy_setopt(result, CURLOPT_USE_SSL, CURLUSESSL_TRY);
 603 #endif
 604
 605         /*
 606          * CURL also examines these variables as a fallback; but we need to query
 607          * them here in order to decide whether to prompt for missing password (cf.
 608          * init_curl_proxy_auth()).
 609          *
 610          * Unlike many other common environment variables, these are historically
 611          * lowercase only. It appears that CURL did not know this and implemented
 612          * only uppercase variants, which was later corrected to take both - with
 613          * the exception of http_proxy, which is lowercase only also in CURL. As
 614          * the lowercase versions are the historical quasi-standard, they take
 615          * precedence here, as in CURL.
 616          */
 617         if (!curl_http_proxy) {
 618                 if (!strcmp(http_auth.protocol, "https")) {
 619                         var_override(&curl_http_proxy, getenv("HTTPS_PROXY"));
 620                         var_override(&curl_http_proxy, getenv("https_proxy"));
 621                 } else {
 622                         var_override(&curl_http_proxy, getenv("http_proxy"));
 623                 }
 624                 if (!curl_http_proxy) {
 625                         var_override(&curl_http_proxy, getenv("ALL_PROXY"));
 626                         var_override(&curl_http_proxy, getenv("all_proxy"));
 627                 }
 628         }
 629
 630         if (curl_http_proxy) {
 631                 curl_easy_setopt(result, CURLOPT_PROXY, curl_http_proxy);
 632 #if LIBCURL_VERSION_NUM >= 0x071800
 633                 if (starts_with(curl_http_proxy, "socks5h"))
 634                         curl_easy_setopt(result,
 635                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5_HOSTNAME);
 636                 else if (starts_with(curl_http_proxy, "socks5"))
 637                         curl_easy_setopt(result,
 638                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5);
 639                 else if (starts_with(curl_http_proxy, "socks4a"))
 640                         curl_easy_setopt(result,
 641                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4A);
 642                 else if (starts_with(curl_http_proxy, "socks"))
 643                         curl_easy_setopt(result,
 644                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4);
 645 #endif
 646                 if (strstr(curl_http_proxy, "://"))
 647                         credential_from_url(&proxy_auth, curl_http_proxy);
 648                 else {
 649                         struct strbuf url = STRBUF_INIT;
 650                         strbuf_addf(&url, "http://%s", curl_http_proxy);
 651                         credential_from_url(&proxy_auth, url.buf);
 652                         strbuf_release(&url);
 653                 }
 654
 655                 curl_easy_setopt(result, CURLOPT_PROXY, proxy_auth.host);
 656 #if LIBCURL_VERSION_NUM >= 0x071304
 657                 var_override(&curl_no_proxy, getenv("NO_PROXY"));
 658                 var_override(&curl_no_proxy, getenv("no_proxy"));
 659                 curl_easy_setopt(result, CURLOPT_NOPROXY, curl_no_proxy);
 660 #endif
 661         }
 662         init_curl_proxy_auth(result);
 663
 664         set_curl_keepalive(result);
 665
 666         return result;
 667 }
 668
 669 static void set_from_env(const char **var, const char *envname)
 670 {
 671         const char *val = getenv(envname);
 672         if (val)
 673                 *var = val;
 674 }
 675
 676 void http_init(struct remote *remote, const char *url, int proactive_auth)
 677 {
 678         char *low_speed_limit;
 679         char *low_speed_time;
 680         char *normalized_url;
 681         struct urlmatch_config config = { STRING_LIST_INIT_DUP };
 682
 683         config.section = "http";
 684         config.key = NULL;
 685         config.collect_fn = http_options;
 686         config.cascade_fn = git_default_config;
 687         config.cb = NULL;
 688
 689         http_is_verbose = 0;
 690         normalized_url = url_normalize(url, &config.url);
 691
 692         git_config(urlmatch_config_entry, &config);
 693         free(normalized_url);
 694
 695         if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK)
 696                 die("curl_global_init failed");
 697
 698         http_proactive_auth = proactive_auth;
 699
 700         if (remote && remote->http_proxy)
 701                 curl_http_proxy = xstrdup(remote->http_proxy);
 702
 703         if (remote)
 704                 var_override(&http_proxy_authmethod, remote->http_proxy_authmethod);
 705
 706         pragma_header = curl_slist_append(http_copy_default_headers(),
 707                 "Pragma: no-cache");
 708         no_pragma_header = curl_slist_append(http_copy_default_headers(),
 709                 "Pragma:");
 710
 711 #ifdef USE_CURL_MULTI
 712         {
 713                 char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
 714                 if (http_max_requests != NULL)
 715                         max_requests = atoi(http_max_requests);
 716         }
 717
 718         curlm = curl_multi_init();
 719         if (!curlm)
 720                 die("curl_multi_init failed");
 721 #endif
 722
 723         if (getenv("GIT_SSL_NO_VERIFY"))
 724                 curl_ssl_verify = 0;
 725
 726         set_from_env(&ssl_cert, "GIT_SSL_CERT");
 727 #if LIBCURL_VERSION_NUM >= 0x070903
 728         set_from_env(&ssl_key, "GIT_SSL_KEY");
 729 #endif
 730 #if LIBCURL_VERSION_NUM >= 0x070908
 731         set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
 732 #endif
 733         set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
 734
 735         set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
 736
 737         low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
 738         if (low_speed_limit != NULL)
 739                 curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
 740         low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
 741         if (low_speed_time != NULL)
 742                 curl_low_speed_time = strtol(low_speed_time, NULL, 10);
 743
 744         if (curl_ssl_verify == -1)
 745                 curl_ssl_verify = 1;
 746
 747         curl_session_count = 0;
 748 #ifdef USE_CURL_MULTI
 749         if (max_requests < 1)
 750                 max_requests = DEFAULT_MAX_REQUESTS;
 751 #endif
 752
 753         if (getenv("GIT_CURL_FTP_NO_EPSV"))
 754                 curl_ftp_no_epsv = 1;
 755
 756         if (url) {
 757                 credential_from_url(&http_auth, url);
 758                 if (!ssl_cert_password_required &&
 759                     getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
 760                     starts_with(url, "https://"))
 761                         ssl_cert_password_required = 1;
 762         }
 763
 764 #ifndef NO_CURL_EASY_DUPHANDLE
 765         curl_default = get_curl_handle();
 766 #endif
 767 }
 768
 769 void http_cleanup(void)
 770 {
 771         struct active_request_slot *slot = active_queue_head;
 772
 773         while (slot != NULL) {
 774                 struct active_request_slot *next = slot->next;
 775                 if (slot->curl != NULL) {
 776 #ifdef USE_CURL_MULTI
 777                         curl_multi_remove_handle(curlm, slot->curl);
 778 #endif
 779                         curl_easy_cleanup(slot->curl);
 780                 }
 781                 free(slot);
 782                 slot = next;
 783         }
 784         active_queue_head = NULL;
 785
 786 #ifndef NO_CURL_EASY_DUPHANDLE
 787         curl_easy_cleanup(curl_default);
 788 #endif
 789
 790 #ifdef USE_CURL_MULTI
 791         curl_multi_cleanup(curlm);
 792 #endif
 793         curl_global_cleanup();
 794
 795         curl_slist_free_all(extra_http_headers);
 796         extra_http_headers = NULL;
 797
 798         curl_slist_free_all(pragma_header);
 799         pragma_header = NULL;
 800
 801         curl_slist_free_all(no_pragma_header);
 802         no_pragma_header = NULL;
 803
 804         if (curl_http_proxy) {
 805                 free((void *)curl_http_proxy);
 806                 curl_http_proxy = NULL;
 807         }
 808
 809         if (proxy_auth.password) {
 810                 memset(proxy_auth.password, 0, strlen(proxy_auth.password));
 811                 free(proxy_auth.password);
 812                 proxy_auth.password = NULL;
 813         }
 814
 815         free((void *)curl_proxyuserpwd);
 816         curl_proxyuserpwd = NULL;
 817
 818         free((void *)http_proxy_authmethod);
 819         http_proxy_authmethod = NULL;
 820
 821         if (cert_auth.password != NULL) {
 822                 memset(cert_auth.password, 0, strlen(cert_auth.password));
 823                 free(cert_auth.password);
 824                 cert_auth.password = NULL;
 825         }
 826         ssl_cert_password_required = 0;
 827
 828         free(cached_accept_language);
 829         cached_accept_language = NULL;
 830 }
 831
 832 struct active_request_slot *get_active_slot(void)
 833 {
 834         struct active_request_slot *slot = active_queue_head;
 835         struct active_request_slot *newslot;
 836
 837 #ifdef USE_CURL_MULTI
 838         int num_transfers;
 839
 840         /* Wait for a slot to open up if the queue is full */
 841         while (active_requests >= max_requests) {
 842                 curl_multi_perform(curlm, &num_transfers);
 843                 if (num_transfers < active_requests)
 844                         process_curl_messages();
 845         }
 846 #endif
 847
 848         while (slot != NULL && slot->in_use)
 849                 slot = slot->next;
 850
 851         if (slot == NULL) {
 852                 newslot = xmalloc(sizeof(*newslot));
 853                 newslot->curl = NULL;
 854                 newslot->in_use = 0;
 855                 newslot->next = NULL;
 856
 857                 slot = active_queue_head;
 858                 if (slot == NULL) {
 859                         active_queue_head = newslot;
 860                 } else {
 861                         while (slot->next != NULL)
 862                                 slot = slot->next;
 863                         slot->next = newslot;
 864                 }
 865                 slot = newslot;
 866         }
 867
 868         if (slot->curl == NULL) {
 869 #ifdef NO_CURL_EASY_DUPHANDLE
 870                 slot->curl = get_curl_handle();
 871 #else
 872                 slot->curl = curl_easy_duphandle(curl_default);
 873 #endif
 874                 curl_session_count++;
 875         }
 876
 877         active_requests++;
 878         slot->in_use = 1;
 879         slot->results = NULL;
 880         slot->finished = NULL;
 881         slot->callback_data = NULL;
 882         slot->callback_func = NULL;
 883         curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
 884         if (curl_save_cookies)
 885                 curl_easy_setopt(slot->curl, CURLOPT_COOKIEJAR, curl_cookie_file);
 886         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
 887         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
 888         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
 889         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
 890         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
 891         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
 892         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
 893         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 894         curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 1);
 895         curl_easy_setopt(slot->curl, CURLOPT_RANGE, NULL);
 896
 897         /*
 898          * Default following to off unless "ALWAYS" is configured; this gives
 899          * callers a sane starting point, and they can tweak for individual
 900          * HTTP_FOLLOW_* cases themselves.
 901          */
 902         if (http_follow_config == HTTP_FOLLOW_ALWAYS)
 903                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 1);
 904         else
 905                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 0);
 906
 907 #if LIBCURL_VERSION_NUM >= 0x070a08
 908         curl_easy_setopt(slot->curl, CURLOPT_IPRESOLVE, git_curl_ipresolve);
 909 #endif
 910 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 911         curl_easy_setopt(slot->curl, CURLOPT_HTTPAUTH, http_auth_methods);
 912 #endif
 913         if (http_auth.password || curl_empty_auth)
 914                 init_curl_http_auth(slot->curl);
 915
 916         return slot;
 917 }
 918
 919 int start_active_slot(struct active_request_slot *slot)
 920 {
 921 #ifdef USE_CURL_MULTI
 922         CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
 923         int num_transfers;
 924
 925         if (curlm_result != CURLM_OK &&
 926             curlm_result != CURLM_CALL_MULTI_PERFORM) {
 927                 active_requests--;
 928                 slot->in_use = 0;
 929                 return 0;
 930         }
 931
 932         /*
 933          * We know there must be something to do, since we just added
 934          * something.
 935          */
 936         curl_multi_perform(curlm, &num_transfers);
 937 #endif
 938         return 1;
 939 }
 940
 941 #ifdef USE_CURL_MULTI
 942 struct fill_chain {
 943         void *data;
 944         int (*fill)(void *);
 945         struct fill_chain *next;
 946 };
 947
 948 static struct fill_chain *fill_cfg;
 949
 950 void add_fill_function(void *data, int (*fill)(void *))
 951 {
 952         struct fill_chain *new = xmalloc(sizeof(*new));
 953         struct fill_chain **linkp = &fill_cfg;
 954         new->data = data;
 955         new->fill = fill;
 956         new->next = NULL;
 957         while (*linkp)
 958                 linkp = &(*linkp)->next;
 959         *linkp = new;
 960 }
 961
 962 void fill_active_slots(void)
 963 {
 964         struct active_request_slot *slot = active_queue_head;
 965
 966         while (active_requests < max_requests) {
 967                 struct fill_chain *fill;
 968                 for (fill = fill_cfg; fill; fill = fill->next)
 969                         if (fill->fill(fill->data))
 970                                 break;
 971
 972                 if (!fill)
 973                         break;
 974         }
 975
 976         while (slot != NULL) {
 977                 if (!slot->in_use && slot->curl != NULL
 978                         && curl_session_count > min_curl_sessions) {
 979                         curl_easy_cleanup(slot->curl);
 980                         slot->curl = NULL;
 981                         curl_session_count--;
 982                 }
 983                 slot = slot->next;
 984         }
 985 }
 986
 987 void step_active_slots(void)
 988 {
 989         int num_transfers;
 990         CURLMcode curlm_result;
 991
 992         do {
 993                 curlm_result = curl_multi_perform(curlm, &num_transfers);
 994         } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
 995         if (num_transfers < active_requests) {
 996                 process_curl_messages();
 997                 fill_active_slots();
 998         }
 999 }
1000 #endif
1001
1002 void run_active_slot(struct active_request_slot *slot)
1003 {
1004 #ifdef USE_CURL_MULTI
1005         fd_set readfds;
1006         fd_set writefds;
1007         fd_set excfds;
1008         int max_fd;
1009         struct timeval select_timeout;
1010         int finished = 0;
1011
1012         slot->finished = &finished;
1013         while (!finished) {
1014                 step_active_slots();
1015
1016                 if (slot->in_use) {
1017 #if LIBCURL_VERSION_NUM >= 0x070f04
1018                         long curl_timeout;
1019                         curl_multi_timeout(curlm, &curl_timeout);
1020                         if (curl_timeout == 0) {
1021                                 continue;
1022                         } else if (curl_timeout == -1) {
1023                                 select_timeout.tv_sec  = 0;
1024                                 select_timeout.tv_usec = 50000;
1025                         } else {
1026                                 select_timeout.tv_sec  =  curl_timeout / 1000;
1027                                 select_timeout.tv_usec = (curl_timeout % 1000) * 1000;
1028                         }
1029 #else
1030                         select_timeout.tv_sec  = 0;
1031                         select_timeout.tv_usec = 50000;
1032 #endif
1033
1034                         max_fd = -1;
1035                         FD_ZERO(&readfds);
1036                         FD_ZERO(&writefds);
1037                         FD_ZERO(&excfds);
1038                         curl_multi_fdset(curlm, &readfds, &writefds, &excfds, &max_fd);
1039
1040                         /*
1041                          * It can happen that curl_multi_timeout returns a pathologically
1042                          * long timeout when curl_multi_fdset returns no file descriptors
1043                          * to read.  See commit message for more details.
1044                          */
1045                         if (max_fd < 0 &&
1046                             (select_timeout.tv_sec > 0 ||
1047                              select_timeout.tv_usec > 50000)) {
1048                                 select_timeout.tv_sec  = 0;
1049                                 select_timeout.tv_usec = 50000;
1050                         }
1051
1052                         select(max_fd+1, &readfds, &writefds, &excfds, &select_timeout);
1053                 }
1054         }
1055 #else
1056         while (slot->in_use) {
1057                 slot->curl_result = curl_easy_perform(slot->curl);
1058                 finish_active_slot(slot);
1059         }
1060 #endif
1061 }
1062
1063 static void release_active_slot(struct active_request_slot *slot)
1064 {
1065         closedown_active_slot(slot);
1066         if (slot->curl && curl_session_count > min_curl_sessions) {
1067 #ifdef USE_CURL_MULTI
1068                 curl_multi_remove_handle(curlm, slot->curl);
1069 #endif
1070                 curl_easy_cleanup(slot->curl);
1071                 slot->curl = NULL;
1072                 curl_session_count--;
1073         }
1074 #ifdef USE_CURL_MULTI
1075         fill_active_slots();
1076 #endif
1077 }
1078
1079 void finish_all_active_slots(void)
1080 {
1081         struct active_request_slot *slot = active_queue_head;
1082
1083         while (slot != NULL)
1084                 if (slot->in_use) {
1085                         run_active_slot(slot);
1086                         slot = active_queue_head;
1087                 } else {
1088                         slot = slot->next;
1089                 }
1090 }
1091
1092 /* Helpers for modifying and creating URLs */
1093 static inline int needs_quote(int ch)
1094 {
1095         if (((ch >= 'A') && (ch <= 'Z'))
1096                         || ((ch >= 'a') && (ch <= 'z'))
1097                         || ((ch >= '0') && (ch <= '9'))
1098                         || (ch == '/')
1099                         || (ch == '-')
1100                         || (ch == '.'))
1101                 return 0;
1102         return 1;
1103 }
1104
1105 static char *quote_ref_url(const char *base, const char *ref)
1106 {
1107         struct strbuf buf = STRBUF_INIT;
1108         const char *cp;
1109         int ch;
1110
1111         end_url_with_slash(&buf, base);
1112
1113         for (cp = ref; (ch = *cp) != 0; cp++)
1114                 if (needs_quote(ch))
1115                         strbuf_addf(&buf, "%%%02x", ch);
1116                 else
1117                         strbuf_addch(&buf, *cp);
1118
1119         return strbuf_detach(&buf, NULL);
1120 }
1121
1122 void append_remote_object_url(struct strbuf *buf, const char *url,
1123                               const char *hex,
1124                               int only_two_digit_prefix)
1125 {
1126         end_url_with_slash(buf, url);
1127
1128         strbuf_addf(buf, "objects/%.*s/", 2, hex);
1129         if (!only_two_digit_prefix)
1130                 strbuf_addstr(buf, hex + 2);
1131 }
1132
1133 char *get_remote_object_url(const char *url, const char *hex,
1134                             int only_two_digit_prefix)
1135 {
1136         struct strbuf buf = STRBUF_INIT;
1137         append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
1138         return strbuf_detach(&buf, NULL);
1139 }
1140
1141 static int handle_curl_result(struct slot_results *results)
1142 {
1143         /*
1144          * If we see a failing http code with CURLE_OK, we have turned off
1145          * FAILONERROR (to keep the server's custom error response), and should
1146          * translate the code into failure here.
1147          *
1148          * Likewise, if we see a redirect (30x code), that means we turned off
1149          * redirect-following, and we should treat the result as an error.
1150          */
1151         if (results->curl_result == CURLE_OK &&
1152             results->http_code >= 300) {
1153                 results->curl_result = CURLE_HTTP_RETURNED_ERROR;
1154                 /*
1155                  * Normally curl will already have put the "reason phrase"
1156                  * from the server into curl_errorstr; unfortunately without
1157                  * FAILONERROR it is lost, so we can give only the numeric
1158                  * status code.
1159                  */
1160                 snprintf(curl_errorstr, sizeof(curl_errorstr),
1161                          "The requested URL returned error: %ld",
1162                          results->http_code);
1163         }
1164
1165         if (results->curl_result == CURLE_OK) {
1166                 credential_approve(&http_auth);
1167                 if (proxy_auth.password)
1168                         credential_approve(&proxy_auth);
1169                 return HTTP_OK;
1170         } else if (missing_target(results))
1171                 return HTTP_MISSING_TARGET;
1172         else if (results->http_code == 401) {
1173                 if (http_auth.username && http_auth.password) {
1174                         credential_reject(&http_auth);
1175                         return HTTP_NOAUTH;
1176                 } else {
1177 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
1178                         http_auth_methods &= ~CURLAUTH_GSSNEGOTIATE;
1179 #endif
1180                         return HTTP_REAUTH;
1181                 }
1182         } else {
1183                 if (results->http_connectcode == 407)
1184                         credential_reject(&proxy_auth);
1185 #if LIBCURL_VERSION_NUM >= 0x070c00
1186                 if (!curl_errorstr[0])
1187                         strlcpy(curl_errorstr,
1188                                 curl_easy_strerror(results->curl_result),
1189                                 sizeof(curl_errorstr));
1190 #endif
1191                 return HTTP_ERROR;
1192         }
1193 }
1194
1195 int run_one_slot(struct active_request_slot *slot,
1196                  struct slot_results *results)
1197 {
1198         slot->results = results;
1199         if (!start_active_slot(slot)) {
1200                 snprintf(curl_errorstr, sizeof(curl_errorstr),
1201                          "failed to start HTTP request");
1202                 return HTTP_START_FAILED;
1203         }
1204
1205         run_active_slot(slot);
1206         return handle_curl_result(results);
1207 }
1208
1209 struct curl_slist *http_copy_default_headers(void)
1210 {
1211         struct curl_slist *headers = NULL, *h;
1212
1213         for (h = extra_http_headers; h; h = h->next)
1214                 headers = curl_slist_append(headers, h->data);
1215
1216         return headers;
1217 }
1218
1219 static CURLcode curlinfo_strbuf(CURL *curl, CURLINFO info, struct strbuf *buf)
1220 {
1221         char *ptr;
1222         CURLcode ret;
1223
1224         strbuf_reset(buf);
1225         ret = curl_easy_getinfo(curl, info, &ptr);
1226         if (!ret && ptr)
1227                 strbuf_addstr(buf, ptr);
1228         return ret;
1229 }
1230
1231 /*
1232  * Check for and extract a content-type parameter. "raw"
1233  * should be positioned at the start of the potential
1234  * parameter, with any whitespace already removed.
1235  *
1236  * "name" is the name of the parameter. The value is appended
1237  * to "out".
1238  */
1239 static int extract_param(const char *raw, const char *name,
1240                          struct strbuf *out)
1241 {
1242         size_t len = strlen(name);
1243
1244         if (strncasecmp(raw, name, len))
1245                 return -1;
1246         raw += len;
1247
1248         if (*raw != '=')
1249                 return -1;
1250         raw++;
1251
1252         while (*raw && !isspace(*raw) && *raw != ';')
1253                 strbuf_addch(out, *raw++);
1254         return 0;
1255 }
1256
1257 /*
1258  * Extract a normalized version of the content type, with any
1259  * spaces suppressed, all letters lowercased, and no trailing ";"
1260  * or parameters.
1261  *
1262  * Note that we will silently remove even invalid whitespace. For
1263  * example, "text / plain" is specifically forbidden by RFC 2616,
1264  * but "text/plain" is the only reasonable output, and this keeps
1265  * our code simple.
1266  *
1267  * If the "charset" argument is not NULL, store the value of any
1268  * charset parameter there.
1269  *
1270  * Example:
1271  *   "TEXT/PLAIN; charset=utf-8" -> "text/plain", "utf-8"
1272  *   "text / plain" -> "text/plain"
1273  */
1274 static void extract_content_type(struct strbuf *raw, struct strbuf *type,
1275                                  struct strbuf *charset)
1276 {
1277         const char *p;
1278
1279         strbuf_reset(type);
1280         strbuf_grow(type, raw->len);
1281         for (p = raw->buf; *p; p++) {
1282                 if (isspace(*p))
1283                         continue;
1284                 if (*p == ';') {
1285                         p++;
1286                         break;
1287                 }
1288                 strbuf_addch(type, tolower(*p));
1289         }
1290
1291         if (!charset)
1292                 return;
1293
1294         strbuf_reset(charset);
1295         while (*p) {
1296                 while (isspace(*p) || *p == ';')
1297                         p++;
1298                 if (!extract_param(p, "charset", charset))
1299                         return;
1300                 while (*p && !isspace(*p))
1301                         p++;
1302         }
1303
1304         if (!charset->len && starts_with(type->buf, "text/"))
1305                 strbuf_addstr(charset, "ISO-8859-1");
1306 }
1307
1308 static void write_accept_language(struct strbuf *buf)
1309 {
1310         /*
1311          * MAX_DECIMAL_PLACES must not be larger than 3. If it is larger than
1312          * that, q-value will be smaller than 0.001, the minimum q-value the
1313          * HTTP specification allows. See
1314          * http://tools.ietf.org/html/rfc7231#section-5.3.1 for q-value.
1315          */
1316         const int MAX_DECIMAL_PLACES = 3;
1317         const int MAX_LANGUAGE_TAGS = 1000;
1318         const int MAX_ACCEPT_LANGUAGE_HEADER_SIZE = 4000;
1319         char **language_tags = NULL;
1320         int num_langs = 0;
1321         const char *s = get_preferred_languages();
1322         int i;
1323         struct strbuf tag = STRBUF_INIT;
1324
1325         /* Don't add Accept-Language header if no language is preferred. */
1326         if (!s)
1327                 return;
1328
1329         /*
1330          * Split the colon-separated string of preferred languages into
1331          * language_tags array.
1332          */
1333         do {
1334                 /* collect language tag */
1335                 for (; *s && (isalnum(*s) || *s == '_'); s++)
1336                         strbuf_addch(&tag, *s == '_' ? '-' : *s);
1337
1338                 /* skip .codeset, @modifier and any other unnecessary parts */
1339                 while (*s && *s != ':')
1340                         s++;
1341
1342                 if (tag.len) {
1343                         num_langs++;
1344                         REALLOC_ARRAY(language_tags, num_langs);
1345                         language_tags[num_langs - 1] = strbuf_detach(&tag, NULL);
1346                         if (num_langs >= MAX_LANGUAGE_TAGS - 1) /* -1 for '*' */
1347                                 break;
1348                 }
1349         } while (*s++);
1350
1351         /* write Accept-Language header into buf */
1352         if (num_langs) {
1353                 int last_buf_len = 0;
1354                 int max_q;
1355                 int decimal_places;
1356                 char q_format[32];
1357
1358                 /* add '*' */
1359                 REALLOC_ARRAY(language_tags, num_langs + 1);
1360                 language_tags[num_langs++] = "*"; /* it's OK; this won't be freed */
1361
1362                 /* compute decimal_places */
1363                 for (max_q = 1, decimal_places = 0;
1364                      max_q < num_langs && decimal_places <= MAX_DECIMAL_PLACES;
1365                      decimal_places++, max_q *= 10)
1366                         ;
1367
1368                 xsnprintf(q_format, sizeof(q_format), ";q=0.%%0%dd", decimal_places);
1369
1370                 strbuf_addstr(buf, "Accept-Language: ");
1371
1372                 for (i = 0; i < num_langs; i++) {
1373                         if (i > 0)
1374                                 strbuf_addstr(buf, ", ");
1375
1376                         strbuf_addstr(buf, language_tags[i]);
1377
1378                         if (i > 0)
1379                                 strbuf_addf(buf, q_format, max_q - i);
1380
1381                         if (buf->len > MAX_ACCEPT_LANGUAGE_HEADER_SIZE) {
1382                                 strbuf_remove(buf, last_buf_len, buf->len - last_buf_len);
1383                                 break;
1384                         }
1385
1386                         last_buf_len = buf->len;
1387                 }
1388         }
1389
1390         /* free language tags -- last one is a static '*' */
1391         for (i = 0; i < num_langs - 1; i++)
1392                 free(language_tags[i]);
1393         free(language_tags);
1394 }
1395
1396 /*
1397  * Get an Accept-Language header which indicates user's preferred languages.
1398  *
1399  * Examples:
1400  *   LANGUAGE= -> ""
1401  *   LANGUAGE=ko:en -> "Accept-Language: ko, en; q=0.9, *; q=0.1"
1402  *   LANGUAGE=ko_KR.UTF-8:sr@latin -> "Accept-Language: ko-KR, sr; q=0.9, *; q=0.1"
1403  *   LANGUAGE=ko LANG=en_US.UTF-8 -> "Accept-Language: ko, *; q=0.1"
1404  *   LANGUAGE= LANG=en_US.UTF-8 -> "Accept-Language: en-US, *; q=0.1"
1405  *   LANGUAGE= LANG=C -> ""
1406  */
1407 static const char *get_accept_language(void)
1408 {
1409         if (!cached_accept_language) {
1410                 struct strbuf buf = STRBUF_INIT;
1411                 write_accept_language(&buf);
1412                 if (buf.len > 0)
1413                         cached_accept_language = strbuf_detach(&buf, NULL);
1414         }
1415
1416         return cached_accept_language;
1417 }
1418
1419 static void http_opt_request_remainder(CURL *curl, off_t pos)
1420 {
1421         char buf[128];
1422         xsnprintf(buf, sizeof(buf), "%"PRIuMAX"-", (uintmax_t)pos);
1423         curl_easy_setopt(curl, CURLOPT_RANGE, buf);
1424 }
1425
1426 /* http_request() targets */
1427 #define HTTP_REQUEST_STRBUF     0
1428 #define HTTP_REQUEST_FILE       1
1429
1430 static int http_request(const char *url,
1431                         void *result, int target,
1432                         const struct http_get_options *options)
1433 {
1434         struct active_request_slot *slot;
1435         struct slot_results results;
1436         struct curl_slist *headers = http_copy_default_headers();
1437         struct strbuf buf = STRBUF_INIT;
1438         const char *accept_language;
1439         int ret;
1440
1441         slot = get_active_slot();
1442         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1443
1444         if (result == NULL) {
1445                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
1446         } else {
1447                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
1448                 curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
1449
1450                 if (target == HTTP_REQUEST_FILE) {
1451                         off_t posn = ftello(result);
1452                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1453                                          fwrite);
1454                         if (posn > 0)
1455                                 http_opt_request_remainder(slot->curl, posn);
1456                 } else
1457                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1458                                          fwrite_buffer);
1459         }
1460
1461         accept_language = get_accept_language();
1462
1463         if (accept_language)
1464                 headers = curl_slist_append(headers, accept_language);
1465
1466         strbuf_addstr(&buf, "Pragma:");
1467         if (options && options->no_cache)
1468                 strbuf_addstr(&buf, " no-cache");
1469         if (options && options->keep_error)
1470                 curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
1471         if (options && options->initial_request &&
1472             http_follow_config == HTTP_FOLLOW_INITIAL)
1473                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 1);
1474
1475         headers = curl_slist_append(headers, buf.buf);
1476
1477         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
1478         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
1479         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "gzip");
1480
1481         ret = run_one_slot(slot, &results);
1482
1483         if (options && options->content_type) {
1484                 struct strbuf raw = STRBUF_INIT;
1485                 curlinfo_strbuf(slot->curl, CURLINFO_CONTENT_TYPE, &raw);
1486                 extract_content_type(&raw, options->content_type,
1487                                      options->charset);
1488                 strbuf_release(&raw);
1489         }
1490
1491         if (options && options->effective_url)
1492                 curlinfo_strbuf(slot->curl, CURLINFO_EFFECTIVE_URL,
1493                                 options->effective_url);
1494
1495         curl_slist_free_all(headers);
1496         strbuf_release(&buf);
1497
1498         return ret;
1499 }
1500
1501 /*
1502  * Update the "base" url to a more appropriate value, as deduced by
1503  * redirects seen when requesting a URL starting with "url".
1504  *
1505  * The "asked" parameter is a URL that we asked curl to access, and must begin
1506  * with "base".
1507  *
1508  * The "got" parameter is the URL that curl reported to us as where we ended
1509  * up.
1510  *
1511  * Returns 1 if we updated the base url, 0 otherwise.
1512  *
1513  * Our basic strategy is to compare "base" and "asked" to find the bits
1514  * specific to our request. We then strip those bits off of "got" to yield the
1515  * new base. So for example, if our base is "http://example.com/foo.git",
1516  * and we ask for "http://example.com/foo.git/info/refs", we might end up
1517  * with "https://other.example.com/foo.git/info/refs". We would want the
1518  * new URL to become "https://other.example.com/foo.git".
1519  *
1520  * Note that this assumes a sane redirect scheme. It's entirely possible
1521  * in the example above to end up at a URL that does not even end in
1522  * "info/refs".  In such a case we die. There's not much we can do, such a
1523  * scheme is unlikely to represent a real git repository, and failing to
1524  * rewrite the base opens options for malicious redirects to do funny things.
1525  */
1526 static int update_url_from_redirect(struct strbuf *base,
1527                                     const char *asked,
1528                                     const struct strbuf *got)
1529 {
1530         const char *tail;
1531         size_t new_len;
1532
1533         if (!strcmp(asked, got->buf))
1534                 return 0;
1535
1536         if (!skip_prefix(asked, base->buf, &tail))
1537                 die("BUG: update_url_from_redirect: %s is not a superset of %s",
1538                     asked, base->buf);
1539
1540         new_len = got->len;
1541         if (!strip_suffix_mem(got->buf, &new_len, tail))
1542                 die(_("unable to update url base from redirection:\n"
1543                       "  asked for: %s\n"
1544                       "   redirect: %s"),
1545                     asked, got->buf);
1546
1547         strbuf_reset(base);
1548         strbuf_add(base, got->buf, new_len);
1549
1550         return 1;
1551 }
1552
1553 static int http_request_reauth(const char *url,
1554                                void *result, int target,
1555                                struct http_get_options *options)
1556 {
1557         int ret = http_request(url, result, target, options);
1558
1559         if (options && options->effective_url && options->base_url) {
1560                 if (update_url_from_redirect(options->base_url,
1561                                              url, options->effective_url)) {
1562                         credential_from_url(&http_auth, options->base_url->buf);
1563                         url = options->effective_url->buf;
1564                 }
1565         }
1566
1567         if (ret != HTTP_REAUTH)
1568                 return ret;
1569
1570         /*
1571          * If we are using KEEP_ERROR, the previous request may have
1572          * put cruft into our output stream; we should clear it out before
1573          * making our next request. We only know how to do this for
1574          * the strbuf case, but that is enough to satisfy current callers.
1575          */
1576         if (options && options->keep_error) {
1577                 switch (target) {
1578                 case HTTP_REQUEST_STRBUF:
1579                         strbuf_reset(result);
1580                         break;
1581                 default:
1582                         die("BUG: HTTP_KEEP_ERROR is only supported with strbufs");
1583                 }
1584         }
1585
1586         credential_fill(&http_auth);
1587
1588         return http_request(url, result, target, options);
1589 }
1590
1591 int http_get_strbuf(const char *url,
1592                     struct strbuf *result,
1593                     struct http_get_options *options)
1594 {
1595         return http_request_reauth(url, result, HTTP_REQUEST_STRBUF, options);
1596 }
1597
1598 /*
1599  * Downloads a URL and stores the result in the given file.
1600  *
1601  * If a previous interrupted download is detected (i.e. a previous temporary
1602  * file is still around) the download is resumed.
1603  */
1604 static int http_get_file(const char *url, const char *filename,
1605                          struct http_get_options *options)
1606 {
1607         int ret;
1608         struct strbuf tmpfile = STRBUF_INIT;
1609         FILE *result;
1610
1611         strbuf_addf(&tmpfile, "%s.temp", filename);
1612         result = fopen(tmpfile.buf, "a");
1613         if (!result) {
1614                 error("Unable to open local file %s", tmpfile.buf);
1615                 ret = HTTP_ERROR;
1616                 goto cleanup;
1617         }
1618
1619         ret = http_request_reauth(url, result, HTTP_REQUEST_FILE, options);
1620         fclose(result);
1621
1622         if (ret == HTTP_OK && finalize_object_file(tmpfile.buf, filename))
1623                 ret = HTTP_ERROR;
1624 cleanup:
1625         strbuf_release(&tmpfile);
1626         return ret;
1627 }
1628
1629 int http_fetch_ref(const char *base, struct ref *ref)
1630 {
1631         struct http_get_options options = {0};
1632         char *url;
1633         struct strbuf buffer = STRBUF_INIT;
1634         int ret = -1;
1635
1636         options.no_cache = 1;
1637
1638         url = quote_ref_url(base, ref->name);
1639         if (http_get_strbuf(url, &buffer, &options) == HTTP_OK) {
1640                 strbuf_rtrim(&buffer);
1641                 if (buffer.len == 40)
1642                         ret = get_oid_hex(buffer.buf, &ref->old_oid);
1643                 else if (starts_with(buffer.buf, "ref: ")) {
1644                         ref->symref = xstrdup(buffer.buf + 5);
1645                         ret = 0;
1646                 }
1647         }
1648
1649         strbuf_release(&buffer);
1650         free(url);
1651         return ret;
1652 }
1653
1654 /* Helpers for fetching packs */
1655 static char *fetch_pack_index(unsigned char *sha1, const char *base_url)
1656 {
1657         char *url, *tmp;
1658         struct strbuf buf = STRBUF_INIT;
1659
1660         if (http_is_verbose)
1661                 fprintf(stderr, "Getting index for pack %s\n", sha1_to_hex(sha1));
1662
1663         end_url_with_slash(&buf, base_url);
1664         strbuf_addf(&buf, "objects/pack/pack-%s.idx", sha1_to_hex(sha1));
1665         url = strbuf_detach(&buf, NULL);
1666
1667         strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(sha1));
1668         tmp = strbuf_detach(&buf, NULL);
1669
1670         if (http_get_file(url, tmp, NULL) != HTTP_OK) {
1671                 error("Unable to get pack index %s", url);
1672                 free(tmp);
1673                 tmp = NULL;
1674         }
1675
1676         free(url);
1677         return tmp;
1678 }
1679
1680 static int fetch_and_setup_pack_index(struct packed_git **packs_head,
1681         unsigned char *sha1, const char *base_url)
1682 {
1683         struct packed_git *new_pack;
1684         char *tmp_idx = NULL;
1685         int ret;
1686
1687         if (has_pack_index(sha1)) {
1688                 new_pack = parse_pack_index(sha1, sha1_pack_index_name(sha1));
1689                 if (!new_pack)
1690                         return -1; /* parse_pack_index() already issued error message */
1691                 goto add_pack;
1692         }
1693
1694         tmp_idx = fetch_pack_index(sha1, base_url);
1695         if (!tmp_idx)
1696                 return -1;
1697
1698         new_pack = parse_pack_index(sha1, tmp_idx);
1699         if (!new_pack) {
1700                 unlink(tmp_idx);
1701                 free(tmp_idx);
1702
1703                 return -1; /* parse_pack_index() already issued error message */
1704         }
1705
1706         ret = verify_pack_index(new_pack);
1707         if (!ret) {
1708                 close_pack_index(new_pack);
1709                 ret = finalize_object_file(tmp_idx, sha1_pack_index_name(sha1));
1710         }
1711         free(tmp_idx);
1712         if (ret)
1713                 return -1;
1714
1715 add_pack:
1716         new_pack->next = *packs_head;
1717         *packs_head = new_pack;
1718         return 0;
1719 }
1720
1721 int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
1722 {
1723         struct http_get_options options = {0};
1724         int ret = 0, i = 0;
1725         char *url, *data;
1726         struct strbuf buf = STRBUF_INIT;
1727         unsigned char sha1[20];
1728
1729         end_url_with_slash(&buf, base_url);
1730         strbuf_addstr(&buf, "objects/info/packs");
1731         url = strbuf_detach(&buf, NULL);
1732
1733         options.no_cache = 1;
1734         ret = http_get_strbuf(url, &buf, &options);
1735         if (ret != HTTP_OK)
1736                 goto cleanup;
1737
1738         data = buf.buf;
1739         while (i < buf.len) {
1740                 switch (data[i]) {
1741                 case 'P':
1742                         i++;
1743                         if (i + 52 <= buf.len &&
1744                             starts_with(data + i, " pack-") &&
1745                             starts_with(data + i + 46, ".pack\n")) {
1746                                 get_sha1_hex(data + i + 6, sha1);
1747                                 fetch_and_setup_pack_index(packs_head, sha1,
1748                                                       base_url);
1749                                 i += 51;
1750                                 break;
1751                         }
1752                 default:
1753                         while (i < buf.len && data[i] != '\n')
1754                                 i++;
1755                 }
1756                 i++;
1757         }
1758
1759 cleanup:
1760         free(url);
1761         return ret;
1762 }
1763
1764 void release_http_pack_request(struct http_pack_request *preq)
1765 {
1766         if (preq->packfile != NULL) {
1767                 fclose(preq->packfile);
1768                 preq->packfile = NULL;
1769         }
1770         preq->slot = NULL;
1771         free(preq->url);
1772         free(preq);
1773 }
1774
1775 int finish_http_pack_request(struct http_pack_request *preq)
1776 {
1777         struct packed_git **lst;
1778         struct packed_git *p = preq->target;
1779         char *tmp_idx;
1780         size_t len;
1781         struct child_process ip = CHILD_PROCESS_INIT;
1782         const char *ip_argv[8];
1783
1784         close_pack_index(p);
1785
1786         fclose(preq->packfile);
1787         preq->packfile = NULL;
1788
1789         lst = preq->lst;
1790         while (*lst != p)
1791                 lst = &((*lst)->next);
1792         *lst = (*lst)->next;
1793
1794         if (!strip_suffix(preq->tmpfile, ".pack.temp", &len))
1795                 die("BUG: pack tmpfile does not end in .pack.temp?");
1796         tmp_idx = xstrfmt("%.*s.idx.temp", (int)len, preq->tmpfile);
1797
1798         ip_argv[0] = "index-pack";
1799         ip_argv[1] = "-o";
1800         ip_argv[2] = tmp_idx;
1801         ip_argv[3] = preq->tmpfile;
1802         ip_argv[4] = NULL;
1803
1804         ip.argv = ip_argv;
1805         ip.git_cmd = 1;
1806         ip.no_stdin = 1;
1807         ip.no_stdout = 1;
1808
1809         if (run_command(&ip)) {
1810                 unlink(preq->tmpfile);
1811                 unlink(tmp_idx);
1812                 free(tmp_idx);
1813                 return -1;
1814         }
1815
1816         unlink(sha1_pack_index_name(p->sha1));
1817
1818         if (finalize_object_file(preq->tmpfile, sha1_pack_name(p->sha1))
1819          || finalize_object_file(tmp_idx, sha1_pack_index_name(p->sha1))) {
1820                 free(tmp_idx);
1821                 return -1;
1822         }
1823
1824         install_packed_git(p);
1825         free(tmp_idx);
1826         return 0;
1827 }
1828
1829 struct http_pack_request *new_http_pack_request(
1830         struct packed_git *target, const char *base_url)
1831 {
1832         off_t prev_posn = 0;
1833         struct strbuf buf = STRBUF_INIT;
1834         struct http_pack_request *preq;
1835
1836         preq = xcalloc(1, sizeof(*preq));
1837         preq->target = target;
1838
1839         end_url_with_slash(&buf, base_url);
1840         strbuf_addf(&buf, "objects/pack/pack-%s.pack",
1841                 sha1_to_hex(target->sha1));
1842         preq->url = strbuf_detach(&buf, NULL);
1843
1844         snprintf(preq->tmpfile, sizeof(preq->tmpfile), "%s.temp",
1845                 sha1_pack_name(target->sha1));
1846         preq->packfile = fopen(preq->tmpfile, "a");
1847         if (!preq->packfile) {
1848                 error("Unable to open local file %s for pack",
1849                       preq->tmpfile);
1850                 goto abort;
1851         }
1852
1853         preq->slot = get_active_slot();
1854         curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
1855         curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
1856         curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
1857         curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1858                 no_pragma_header);
1859
1860         /*
1861          * If there is data present from a previous transfer attempt,
1862          * resume where it left off
1863          */
1864         prev_posn = ftello(preq->packfile);
1865         if (prev_posn>0) {
1866                 if (http_is_verbose)
1867                         fprintf(stderr,
1868                                 "Resuming fetch of pack %s at byte %"PRIuMAX"\n",
1869                                 sha1_to_hex(target->sha1), (uintmax_t)prev_posn);
1870                 http_opt_request_remainder(preq->slot->curl, prev_posn);
1871         }
1872
1873         return preq;
1874
1875 abort:
1876         free(preq->url);
1877         free(preq);
1878         return NULL;
1879 }
1880
1881 /* Helpers for fetching objects (loose) */
1882 static size_t fwrite_sha1_file(char *ptr, size_t eltsize, size_t nmemb,
1883                                void *data)
1884 {
1885         unsigned char expn[4096];
1886         size_t size = eltsize * nmemb;
1887         int posn = 0;
1888         struct http_object_request *freq = data;
1889         struct active_request_slot *slot = freq->slot;
1890
1891         if (slot) {
1892                 CURLcode c = curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE,
1893                                                 &slot->http_code);
1894                 if (c != CURLE_OK)
1895                         die("BUG: curl_easy_getinfo for HTTP code failed: %s",
1896                                 curl_easy_strerror(c));
1897                 if (slot->http_code >= 300)
1898                         return size;
1899         }
1900
1901         do {
1902                 ssize_t retval = xwrite(freq->localfile,
1903                                         (char *) ptr + posn, size - posn);
1904                 if (retval < 0)
1905                         return posn;
1906                 posn += retval;
1907         } while (posn < size);
1908
1909         freq->stream.avail_in = size;
1910         freq->stream.next_in = (void *)ptr;
1911         do {
1912                 freq->stream.next_out = expn;
1913                 freq->stream.avail_out = sizeof(expn);
1914                 freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
1915                 git_SHA1_Update(&freq->c, expn,
1916                                 sizeof(expn) - freq->stream.avail_out);
1917         } while (freq->stream.avail_in && freq->zret == Z_OK);
1918         return size;
1919 }
1920
1921 struct http_object_request *new_http_object_request(const char *base_url,
1922         unsigned char *sha1)
1923 {
1924         char *hex = sha1_to_hex(sha1);
1925         const char *filename;
1926         char prevfile[PATH_MAX];
1927         int prevlocal;
1928         char prev_buf[PREV_BUF_SIZE];
1929         ssize_t prev_read = 0;
1930         off_t prev_posn = 0;
1931         struct http_object_request *freq;
1932
1933         freq = xcalloc(1, sizeof(*freq));
1934         hashcpy(freq->sha1, sha1);
1935         freq->localfile = -1;
1936
1937         filename = sha1_file_name(sha1);
1938         snprintf(freq->tmpfile, sizeof(freq->tmpfile),
1939                  "%s.temp", filename);
1940
1941         snprintf(prevfile, sizeof(prevfile), "%s.prev", filename);
1942         unlink_or_warn(prevfile);
1943         rename(freq->tmpfile, prevfile);
1944         unlink_or_warn(freq->tmpfile);
1945
1946         if (freq->localfile != -1)
1947                 error("fd leakage in start: %d", freq->localfile);
1948         freq->localfile = open(freq->tmpfile,
1949                                O_WRONLY | O_CREAT | O_EXCL, 0666);
1950         /*
1951          * This could have failed due to the "lazy directory creation";
1952          * try to mkdir the last path component.
1953          */
1954         if (freq->localfile < 0 && errno == ENOENT) {
1955                 char *dir = strrchr(freq->tmpfile, '/');
1956                 if (dir) {
1957                         *dir = 0;
1958                         mkdir(freq->tmpfile, 0777);
1959                         *dir = '/';
1960                 }
1961                 freq->localfile = open(freq->tmpfile,
1962                                        O_WRONLY | O_CREAT | O_EXCL, 0666);
1963         }
1964
1965         if (freq->localfile < 0) {
1966                 error_errno("Couldn't create temporary file %s", freq->tmpfile);
1967                 goto abort;
1968         }
1969
1970         git_inflate_init(&freq->stream);
1971
1972         git_SHA1_Init(&freq->c);
1973
1974         freq->url = get_remote_object_url(base_url, hex, 0);
1975
1976         /*
1977          * If a previous temp file is present, process what was already
1978          * fetched.
1979          */
1980         prevlocal = open(prevfile, O_RDONLY);
1981         if (prevlocal != -1) {
1982                 do {
1983                         prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
1984                         if (prev_read>0) {
1985                                 if (fwrite_sha1_file(prev_buf,
1986                                                      1,
1987                                                      prev_read,
1988                                                      freq) == prev_read) {
1989                                         prev_posn += prev_read;
1990                                 } else {
1991                                         prev_read = -1;
1992                                 }
1993                         }
1994                 } while (prev_read > 0);
1995                 close(prevlocal);
1996         }
1997         unlink_or_warn(prevfile);
1998
1999         /*
2000          * Reset inflate/SHA1 if there was an error reading the previous temp
2001          * file; also rewind to the beginning of the local file.
2002          */
2003         if (prev_read == -1) {
2004                 memset(&freq->stream, 0, sizeof(freq->stream));
2005                 git_inflate_init(&freq->stream);
2006                 git_SHA1_Init(&freq->c);
2007                 if (prev_posn>0) {
2008                         prev_posn = 0;
2009                         lseek(freq->localfile, 0, SEEK_SET);
2010                         if (ftruncate(freq->localfile, 0) < 0) {
2011                                 error_errno("Couldn't truncate temporary file %s",
2012                                             freq->tmpfile);
2013                                 goto abort;
2014                         }
2015                 }
2016         }
2017
2018         freq->slot = get_active_slot();
2019
2020         curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
2021         curl_easy_setopt(freq->slot->curl, CURLOPT_FAILONERROR, 0);
2022         curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
2023         curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
2024         curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
2025         curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
2026
2027         /*
2028          * If we have successfully processed data from a previous fetch
2029          * attempt, only fetch the data we don't already have.
2030          */
2031         if (prev_posn>0) {
2032                 if (http_is_verbose)
2033                         fprintf(stderr,
2034                                 "Resuming fetch of object %s at byte %"PRIuMAX"\n",
2035                                 hex, (uintmax_t)prev_posn);
2036                 http_opt_request_remainder(freq->slot->curl, prev_posn);
2037         }
2038
2039         return freq;
2040
2041 abort:
2042         free(freq->url);
2043         free(freq);
2044         return NULL;
2045 }
2046
2047 void process_http_object_request(struct http_object_request *freq)
2048 {
2049         if (freq->slot == NULL)
2050                 return;
2051         freq->curl_result = freq->slot->curl_result;
2052         freq->http_code = freq->slot->http_code;
2053         freq->slot = NULL;
2054 }
2055
2056 int finish_http_object_request(struct http_object_request *freq)
2057 {
2058         struct stat st;
2059
2060         close(freq->localfile);
2061         freq->localfile = -1;
2062
2063         process_http_object_request(freq);
2064
2065         if (freq->http_code == 416) {
2066                 warning("requested range invalid; we may already have all the data.");
2067         } else if (freq->curl_result != CURLE_OK) {
2068                 if (stat(freq->tmpfile, &st) == 0)
2069                         if (st.st_size == 0)
2070                                 unlink_or_warn(freq->tmpfile);
2071                 return -1;
2072         }
2073
2074         git_inflate_end(&freq->stream);
2075         git_SHA1_Final(freq->real_sha1, &freq->c);
2076         if (freq->zret != Z_STREAM_END) {
2077                 unlink_or_warn(freq->tmpfile);
2078                 return -1;
2079         }
2080         if (hashcmp(freq->sha1, freq->real_sha1)) {
2081                 unlink_or_warn(freq->tmpfile);
2082                 return -1;
2083         }
2084         freq->rename =
2085                 finalize_object_file(freq->tmpfile, sha1_file_name(freq->sha1));
2086
2087         return freq->rename;
2088 }
2089
2090 void abort_http_object_request(struct http_object_request *freq)
2091 {
2092         unlink_or_warn(freq->tmpfile);
2093
2094         release_http_object_request(freq);
2095 }
2096
2097 void release_http_object_request(struct http_object_request *freq)
2098 {
2099         if (freq->localfile != -1) {
2100                 close(freq->localfile);
2101                 freq->localfile = -1;
2102         }
2103         if (freq->url != NULL) {
2104                 free(freq->url);
2105                 freq->url = NULL;
2106         }
2107         if (freq->slot != NULL) {
2108                 freq->slot->callback_func = NULL;
2109                 freq->slot->callback_data = NULL;
2110                 release_active_slot(freq->slot);
2111                 freq->slot = NULL;
2112         }
2113 }