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
  13 int active_requests;
  14 int http_is_verbose;
  15 size_t http_post_buffer = 16 * LARGE_PACKET_MAX;
  16
  17 #if LIBCURL_VERSION_NUM >= 0x070a06
  18 #define LIBCURL_CAN_HANDLE_AUTH_ANY
  19 #endif
  20
  21 static int min_curl_sessions = 1;
  22 static int curl_session_count;
  23 #ifdef USE_CURL_MULTI
  24 static int max_requests = -1;
  25 static CURLM *curlm;
  26 #endif
  27 #ifndef NO_CURL_EASY_DUPHANDLE
  28 static CURL *curl_default;
  29 #endif
  30
  31 #define PREV_BUF_SIZE 4096
  32 #define RANGE_HEADER_SIZE 30
  33
  34 char curl_errorstr[CURL_ERROR_SIZE];
  35
  36 static int curl_ssl_verify = -1;
  37 static int curl_ssl_try;
  38 static const char *ssl_cert;
  39 #if LIBCURL_VERSION_NUM >= 0x070903
  40 static const char *ssl_key;
  41 #endif
  42 #if LIBCURL_VERSION_NUM >= 0x070908
  43 static const char *ssl_capath;
  44 #endif
  45 static const char *ssl_cainfo;
  46 static long curl_low_speed_limit = -1;
  47 static long curl_low_speed_time = -1;
  48 static int curl_ftp_no_epsv;
  49 static const char *curl_http_proxy;
  50 static const char *curl_cookie_file;
  51 static int curl_save_cookies;
  52 struct credential http_auth = CREDENTIAL_INIT;
  53 static int http_proactive_auth;
  54 static const char *user_agent;
  55
  56 #if LIBCURL_VERSION_NUM >= 0x071700
  57 /* Use CURLOPT_KEYPASSWD as is */
  58 #elif LIBCURL_VERSION_NUM >= 0x070903
  59 #define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
  60 #else
  61 #define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
  62 #endif
  63
  64 static struct credential cert_auth = CREDENTIAL_INIT;
  65 static int ssl_cert_password_required;
  66
  67 static struct curl_slist *pragma_header;
  68 static struct curl_slist *no_pragma_header;
  69
  70 static struct active_request_slot *active_queue_head;
  71
  72 static char *cached_accept_language;
  73
  74 size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
  75 {
  76         size_t size = eltsize * nmemb;
  77         struct buffer *buffer = buffer_;
  78
  79         if (size > buffer->buf.len - buffer->posn)
  80                 size = buffer->buf.len - buffer->posn;
  81         memcpy(ptr, buffer->buf.buf + buffer->posn, size);
  82         buffer->posn += size;
  83
  84         return size;
  85 }
  86
  87 #ifndef NO_CURL_IOCTL
  88 curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
  89 {
  90         struct buffer *buffer = clientp;
  91
  92         switch (cmd) {
  93         case CURLIOCMD_NOP:
  94                 return CURLIOE_OK;
  95
  96         case CURLIOCMD_RESTARTREAD:
  97                 buffer->posn = 0;
  98                 return CURLIOE_OK;
  99
 100         default:
 101                 return CURLIOE_UNKNOWNCMD;
 102         }
 103 }
 104 #endif
 105
 106 size_t fwrite_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
 107 {
 108         size_t size = eltsize * nmemb;
 109         struct strbuf *buffer = buffer_;
 110
 111         strbuf_add(buffer, ptr, size);
 112         return size;
 113 }
 114
 115 size_t fwrite_null(char *ptr, size_t eltsize, size_t nmemb, void *strbuf)
 116 {
 117         return eltsize * nmemb;
 118 }
 119
 120 #ifdef USE_CURL_MULTI
 121 static void process_curl_messages(void)
 122 {
 123         int num_messages;
 124         struct active_request_slot *slot;
 125         CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
 126
 127         while (curl_message != NULL) {
 128                 if (curl_message->msg == CURLMSG_DONE) {
 129                         int curl_result = curl_message->data.result;
 130                         slot = active_queue_head;
 131                         while (slot != NULL &&
 132                                slot->curl != curl_message->easy_handle)
 133                                 slot = slot->next;
 134                         if (slot != NULL) {
 135                                 curl_multi_remove_handle(curlm, slot->curl);
 136                                 slot->curl_result = curl_result;
 137                                 finish_active_slot(slot);
 138                         } else {
 139                                 fprintf(stderr, "Received DONE message for unknown request!\n");
 140                         }
 141                 } else {
 142                         fprintf(stderr, "Unknown CURL message received: %d\n",
 143                                 (int)curl_message->msg);
 144                 }
 145                 curl_message = curl_multi_info_read(curlm, &num_messages);
 146         }
 147 }
 148 #endif
 149
 150 static int http_options(const char *var, const char *value, void *cb)
 151 {
 152         if (!strcmp("http.sslverify", var)) {
 153                 curl_ssl_verify = git_config_bool(var, value);
 154                 return 0;
 155         }
 156         if (!strcmp("http.sslcert", var))
 157                 return git_config_string(&ssl_cert, var, value);
 158 #if LIBCURL_VERSION_NUM >= 0x070903
 159         if (!strcmp("http.sslkey", var))
 160                 return git_config_string(&ssl_key, var, value);
 161 #endif
 162 #if LIBCURL_VERSION_NUM >= 0x070908
 163         if (!strcmp("http.sslcapath", var))
 164                 return git_config_string(&ssl_capath, var, value);
 165 #endif
 166         if (!strcmp("http.sslcainfo", var))
 167                 return git_config_string(&ssl_cainfo, var, value);
 168         if (!strcmp("http.sslcertpasswordprotected", var)) {
 169                 ssl_cert_password_required = git_config_bool(var, value);
 170                 return 0;
 171         }
 172         if (!strcmp("http.ssltry", var)) {
 173                 curl_ssl_try = git_config_bool(var, value);
 174                 return 0;
 175         }
 176         if (!strcmp("http.minsessions", var)) {
 177                 min_curl_sessions = git_config_int(var, value);
 178 #ifndef USE_CURL_MULTI
 179                 if (min_curl_sessions > 1)
 180                         min_curl_sessions = 1;
 181 #endif
 182                 return 0;
 183         }
 184 #ifdef USE_CURL_MULTI
 185         if (!strcmp("http.maxrequests", var)) {
 186                 max_requests = git_config_int(var, value);
 187                 return 0;
 188         }
 189 #endif
 190         if (!strcmp("http.lowspeedlimit", var)) {
 191                 curl_low_speed_limit = (long)git_config_int(var, value);
 192                 return 0;
 193         }
 194         if (!strcmp("http.lowspeedtime", var)) {
 195                 curl_low_speed_time = (long)git_config_int(var, value);
 196                 return 0;
 197         }
 198
 199         if (!strcmp("http.noepsv", var)) {
 200                 curl_ftp_no_epsv = git_config_bool(var, value);
 201                 return 0;
 202         }
 203         if (!strcmp("http.proxy", var))
 204                 return git_config_string(&curl_http_proxy, var, value);
 205
 206         if (!strcmp("http.cookiefile", var))
 207                 return git_config_string(&curl_cookie_file, var, value);
 208         if (!strcmp("http.savecookies", var)) {
 209                 curl_save_cookies = git_config_bool(var, value);
 210                 return 0;
 211         }
 212
 213         if (!strcmp("http.postbuffer", var)) {
 214                 http_post_buffer = git_config_int(var, value);
 215                 if (http_post_buffer < LARGE_PACKET_MAX)
 216                         http_post_buffer = LARGE_PACKET_MAX;
 217                 return 0;
 218         }
 219
 220         if (!strcmp("http.useragent", var))
 221                 return git_config_string(&user_agent, var, value);
 222
 223         /* Fall back on the default ones */
 224         return git_default_config(var, value, cb);
 225 }
 226
 227 static void init_curl_http_auth(CURL *result)
 228 {
 229         if (!http_auth.username)
 230                 return;
 231
 232         credential_fill(&http_auth);
 233
 234 #if LIBCURL_VERSION_NUM >= 0x071301
 235         curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username);
 236         curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password);
 237 #else
 238         {
 239                 static struct strbuf up = STRBUF_INIT;
 240                 /*
 241                  * Note that we assume we only ever have a single set of
 242                  * credentials in a given program run, so we do not have
 243                  * to worry about updating this buffer, only setting its
 244                  * initial value.
 245                  */
 246                 if (!up.len)
 247                         strbuf_addf(&up, "%s:%s",
 248                                 http_auth.username, http_auth.password);
 249                 curl_easy_setopt(result, CURLOPT_USERPWD, up.buf);
 250         }
 251 #endif
 252 }
 253
 254 static int has_cert_password(void)
 255 {
 256         if (ssl_cert == NULL || ssl_cert_password_required != 1)
 257                 return 0;
 258         if (!cert_auth.password) {
 259                 cert_auth.protocol = xstrdup("cert");
 260                 cert_auth.username = xstrdup("");
 261                 cert_auth.path = xstrdup(ssl_cert);
 262                 credential_fill(&cert_auth);
 263         }
 264         return 1;
 265 }
 266
 267 #if LIBCURL_VERSION_NUM >= 0x071900
 268 static void set_curl_keepalive(CURL *c)
 269 {
 270         curl_easy_setopt(c, CURLOPT_TCP_KEEPALIVE, 1);
 271 }
 272
 273 #elif LIBCURL_VERSION_NUM >= 0x071000
 274 static int sockopt_callback(void *client, curl_socket_t fd, curlsocktype type)
 275 {
 276         int ka = 1;
 277         int rc;
 278         socklen_t len = (socklen_t)sizeof(ka);
 279
 280         if (type != CURLSOCKTYPE_IPCXN)
 281                 return 0;
 282
 283         rc = setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&ka, len);
 284         if (rc < 0)
 285                 warning("unable to set SO_KEEPALIVE on socket %s",
 286                         strerror(errno));
 287
 288         return 0; /* CURL_SOCKOPT_OK only exists since curl 7.21.5 */
 289 }
 290
 291 static void set_curl_keepalive(CURL *c)
 292 {
 293         curl_easy_setopt(c, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
 294 }
 295
 296 #else
 297 static void set_curl_keepalive(CURL *c)
 298 {
 299         /* not supported on older curl versions */
 300 }
 301 #endif
 302
 303 static CURL *get_curl_handle(void)
 304 {
 305         CURL *result = curl_easy_init();
 306
 307         if (!result)
 308                 die("curl_easy_init failed");
 309
 310         if (!curl_ssl_verify) {
 311                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
 312                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
 313         } else {
 314                 /* Verify authenticity of the peer's certificate */
 315                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
 316                 /* The name in the cert must match whom we tried to connect */
 317                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
 318         }
 319
 320 #if LIBCURL_VERSION_NUM >= 0x070907
 321         curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
 322 #endif
 323 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 324         curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 325 #endif
 326
 327         if (http_proactive_auth)
 328                 init_curl_http_auth(result);
 329
 330         if (ssl_cert != NULL)
 331                 curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
 332         if (has_cert_password())
 333                 curl_easy_setopt(result, CURLOPT_KEYPASSWD, cert_auth.password);
 334 #if LIBCURL_VERSION_NUM >= 0x070903
 335         if (ssl_key != NULL)
 336                 curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
 337 #endif
 338 #if LIBCURL_VERSION_NUM >= 0x070908
 339         if (ssl_capath != NULL)
 340                 curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
 341 #endif
 342         if (ssl_cainfo != NULL)
 343                 curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
 344
 345         if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
 346                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
 347                                  curl_low_speed_limit);
 348                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
 349                                  curl_low_speed_time);
 350         }
 351
 352         curl_easy_setopt(result, CURLOPT_FOLLOWLOCATION, 1);
 353 #if LIBCURL_VERSION_NUM >= 0x071301
 354         curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
 355 #elif LIBCURL_VERSION_NUM >= 0x071101
 356         curl_easy_setopt(result, CURLOPT_POST301, 1);
 357 #endif
 358
 359         if (getenv("GIT_CURL_VERBOSE"))
 360                 curl_easy_setopt(result, CURLOPT_VERBOSE, 1);
 361
 362         curl_easy_setopt(result, CURLOPT_USERAGENT,
 363                 user_agent ? user_agent : git_user_agent());
 364
 365         if (curl_ftp_no_epsv)
 366                 curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
 367
 368 #ifdef CURLOPT_USE_SSL
 369         if (curl_ssl_try)
 370                 curl_easy_setopt(result, CURLOPT_USE_SSL, CURLUSESSL_TRY);
 371 #endif
 372
 373         if (curl_http_proxy) {
 374                 curl_easy_setopt(result, CURLOPT_PROXY, curl_http_proxy);
 375                 curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 376         }
 377
 378         set_curl_keepalive(result);
 379
 380         return result;
 381 }
 382
 383 static void set_from_env(const char **var, const char *envname)
 384 {
 385         const char *val = getenv(envname);
 386         if (val)
 387                 *var = val;
 388 }
 389
 390 void http_init(struct remote *remote, const char *url, int proactive_auth)
 391 {
 392         char *low_speed_limit;
 393         char *low_speed_time;
 394         char *normalized_url;
 395         struct urlmatch_config config = { STRING_LIST_INIT_DUP };
 396
 397         config.section = "http";
 398         config.key = NULL;
 399         config.collect_fn = http_options;
 400         config.cascade_fn = git_default_config;
 401         config.cb = NULL;
 402
 403         http_is_verbose = 0;
 404         normalized_url = url_normalize(url, &config.url);
 405
 406         git_config(urlmatch_config_entry, &config);
 407         free(normalized_url);
 408
 409         if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK)
 410                 die("curl_global_init failed");
 411
 412         http_proactive_auth = proactive_auth;
 413
 414         if (remote && remote->http_proxy)
 415                 curl_http_proxy = xstrdup(remote->http_proxy);
 416
 417         pragma_header = curl_slist_append(pragma_header, "Pragma: no-cache");
 418         no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
 419
 420 #ifdef USE_CURL_MULTI
 421         {
 422                 char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
 423                 if (http_max_requests != NULL)
 424                         max_requests = atoi(http_max_requests);
 425         }
 426
 427         curlm = curl_multi_init();
 428         if (!curlm)
 429                 die("curl_multi_init failed");
 430 #endif
 431
 432         if (getenv("GIT_SSL_NO_VERIFY"))
 433                 curl_ssl_verify = 0;
 434
 435         set_from_env(&ssl_cert, "GIT_SSL_CERT");
 436 #if LIBCURL_VERSION_NUM >= 0x070903
 437         set_from_env(&ssl_key, "GIT_SSL_KEY");
 438 #endif
 439 #if LIBCURL_VERSION_NUM >= 0x070908
 440         set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
 441 #endif
 442         set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
 443
 444         set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
 445
 446         low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
 447         if (low_speed_limit != NULL)
 448                 curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
 449         low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
 450         if (low_speed_time != NULL)
 451                 curl_low_speed_time = strtol(low_speed_time, NULL, 10);
 452
 453         if (curl_ssl_verify == -1)
 454                 curl_ssl_verify = 1;
 455
 456         curl_session_count = 0;
 457 #ifdef USE_CURL_MULTI
 458         if (max_requests < 1)
 459                 max_requests = DEFAULT_MAX_REQUESTS;
 460 #endif
 461
 462         if (getenv("GIT_CURL_FTP_NO_EPSV"))
 463                 curl_ftp_no_epsv = 1;
 464
 465         if (url) {
 466                 credential_from_url(&http_auth, url);
 467                 if (!ssl_cert_password_required &&
 468                     getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
 469                     starts_with(url, "https://"))
 470                         ssl_cert_password_required = 1;
 471         }
 472
 473 #ifndef NO_CURL_EASY_DUPHANDLE
 474         curl_default = get_curl_handle();
 475 #endif
 476 }
 477
 478 void http_cleanup(void)
 479 {
 480         struct active_request_slot *slot = active_queue_head;
 481
 482         while (slot != NULL) {
 483                 struct active_request_slot *next = slot->next;
 484                 if (slot->curl != NULL) {
 485 #ifdef USE_CURL_MULTI
 486                         curl_multi_remove_handle(curlm, slot->curl);
 487 #endif
 488                         curl_easy_cleanup(slot->curl);
 489                 }
 490                 free(slot);
 491                 slot = next;
 492         }
 493         active_queue_head = NULL;
 494
 495 #ifndef NO_CURL_EASY_DUPHANDLE
 496         curl_easy_cleanup(curl_default);
 497 #endif
 498
 499 #ifdef USE_CURL_MULTI
 500         curl_multi_cleanup(curlm);
 501 #endif
 502         curl_global_cleanup();
 503
 504         curl_slist_free_all(pragma_header);
 505         pragma_header = NULL;
 506
 507         curl_slist_free_all(no_pragma_header);
 508         no_pragma_header = NULL;
 509
 510         if (curl_http_proxy) {
 511                 free((void *)curl_http_proxy);
 512                 curl_http_proxy = NULL;
 513         }
 514
 515         if (cert_auth.password != NULL) {
 516                 memset(cert_auth.password, 0, strlen(cert_auth.password));
 517                 free(cert_auth.password);
 518                 cert_auth.password = NULL;
 519         }
 520         ssl_cert_password_required = 0;
 521
 522         free(cached_accept_language);
 523         cached_accept_language = NULL;
 524 }
 525
 526 struct active_request_slot *get_active_slot(void)
 527 {
 528         struct active_request_slot *slot = active_queue_head;
 529         struct active_request_slot *newslot;
 530
 531 #ifdef USE_CURL_MULTI
 532         int num_transfers;
 533
 534         /* Wait for a slot to open up if the queue is full */
 535         while (active_requests >= max_requests) {
 536                 curl_multi_perform(curlm, &num_transfers);
 537                 if (num_transfers < active_requests)
 538                         process_curl_messages();
 539         }
 540 #endif
 541
 542         while (slot != NULL && slot->in_use)
 543                 slot = slot->next;
 544
 545         if (slot == NULL) {
 546                 newslot = xmalloc(sizeof(*newslot));
 547                 newslot->curl = NULL;
 548                 newslot->in_use = 0;
 549                 newslot->next = NULL;
 550
 551                 slot = active_queue_head;
 552                 if (slot == NULL) {
 553                         active_queue_head = newslot;
 554                 } else {
 555                         while (slot->next != NULL)
 556                                 slot = slot->next;
 557                         slot->next = newslot;
 558                 }
 559                 slot = newslot;
 560         }
 561
 562         if (slot->curl == NULL) {
 563 #ifdef NO_CURL_EASY_DUPHANDLE
 564                 slot->curl = get_curl_handle();
 565 #else
 566                 slot->curl = curl_easy_duphandle(curl_default);
 567 #endif
 568                 curl_session_count++;
 569         }
 570
 571         active_requests++;
 572         slot->in_use = 1;
 573         slot->results = NULL;
 574         slot->finished = NULL;
 575         slot->callback_data = NULL;
 576         slot->callback_func = NULL;
 577         curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
 578         if (curl_save_cookies)
 579                 curl_easy_setopt(slot->curl, CURLOPT_COOKIEJAR, curl_cookie_file);
 580         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
 581         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
 582         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
 583         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
 584         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
 585         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
 586         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
 587         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 588         curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 1);
 589         if (http_auth.password)
 590                 init_curl_http_auth(slot->curl);
 591
 592         return slot;
 593 }
 594
 595 int start_active_slot(struct active_request_slot *slot)
 596 {
 597 #ifdef USE_CURL_MULTI
 598         CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
 599         int num_transfers;
 600
 601         if (curlm_result != CURLM_OK &&
 602             curlm_result != CURLM_CALL_MULTI_PERFORM) {
 603                 active_requests--;
 604                 slot->in_use = 0;
 605                 return 0;
 606         }
 607
 608         /*
 609          * We know there must be something to do, since we just added
 610          * something.
 611          */
 612         curl_multi_perform(curlm, &num_transfers);
 613 #endif
 614         return 1;
 615 }
 616
 617 #ifdef USE_CURL_MULTI
 618 struct fill_chain {
 619         void *data;
 620         int (*fill)(void *);
 621         struct fill_chain *next;
 622 };
 623
 624 static struct fill_chain *fill_cfg;
 625
 626 void add_fill_function(void *data, int (*fill)(void *))
 627 {
 628         struct fill_chain *new = xmalloc(sizeof(*new));
 629         struct fill_chain **linkp = &fill_cfg;
 630         new->data = data;
 631         new->fill = fill;
 632         new->next = NULL;
 633         while (*linkp)
 634                 linkp = &(*linkp)->next;
 635         *linkp = new;
 636 }
 637
 638 void fill_active_slots(void)
 639 {
 640         struct active_request_slot *slot = active_queue_head;
 641
 642         while (active_requests < max_requests) {
 643                 struct fill_chain *fill;
 644                 for (fill = fill_cfg; fill; fill = fill->next)
 645                         if (fill->fill(fill->data))
 646                                 break;
 647
 648                 if (!fill)
 649                         break;
 650         }
 651
 652         while (slot != NULL) {
 653                 if (!slot->in_use && slot->curl != NULL
 654                         && curl_session_count > min_curl_sessions) {
 655                         curl_easy_cleanup(slot->curl);
 656                         slot->curl = NULL;
 657                         curl_session_count--;
 658                 }
 659                 slot = slot->next;
 660         }
 661 }
 662
 663 void step_active_slots(void)
 664 {
 665         int num_transfers;
 666         CURLMcode curlm_result;
 667
 668         do {
 669                 curlm_result = curl_multi_perform(curlm, &num_transfers);
 670         } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
 671         if (num_transfers < active_requests) {
 672                 process_curl_messages();
 673                 fill_active_slots();
 674         }
 675 }
 676 #endif
 677
 678 void run_active_slot(struct active_request_slot *slot)
 679 {
 680 #ifdef USE_CURL_MULTI
 681         fd_set readfds;
 682         fd_set writefds;
 683         fd_set excfds;
 684         int max_fd;
 685         struct timeval select_timeout;
 686         int finished = 0;
 687
 688         slot->finished = &finished;
 689         while (!finished) {
 690                 step_active_slots();
 691
 692                 if (slot->in_use) {
 693 #if LIBCURL_VERSION_NUM >= 0x070f04
 694                         long curl_timeout;
 695                         curl_multi_timeout(curlm, &curl_timeout);
 696                         if (curl_timeout == 0) {
 697                                 continue;
 698                         } else if (curl_timeout == -1) {
 699                                 select_timeout.tv_sec  = 0;
 700                                 select_timeout.tv_usec = 50000;
 701                         } else {
 702                                 select_timeout.tv_sec  =  curl_timeout / 1000;
 703                                 select_timeout.tv_usec = (curl_timeout % 1000) * 1000;
 704                         }
 705 #else
 706                         select_timeout.tv_sec  = 0;
 707                         select_timeout.tv_usec = 50000;
 708 #endif
 709
 710                         max_fd = -1;
 711                         FD_ZERO(&readfds);
 712                         FD_ZERO(&writefds);
 713                         FD_ZERO(&excfds);
 714                         curl_multi_fdset(curlm, &readfds, &writefds, &excfds, &max_fd);
 715
 716                         /*
 717                          * It can happen that curl_multi_timeout returns a pathologically
 718                          * long timeout when curl_multi_fdset returns no file descriptors
 719                          * to read.  See commit message for more details.
 720                          */
 721                         if (max_fd < 0 &&
 722                             (select_timeout.tv_sec > 0 ||
 723                              select_timeout.tv_usec > 50000)) {
 724                                 select_timeout.tv_sec  = 0;
 725                                 select_timeout.tv_usec = 50000;
 726                         }
 727
 728                         select(max_fd+1, &readfds, &writefds, &excfds, &select_timeout);
 729                 }
 730         }
 731 #else
 732         while (slot->in_use) {
 733                 slot->curl_result = curl_easy_perform(slot->curl);
 734                 finish_active_slot(slot);
 735         }
 736 #endif
 737 }
 738
 739 static void closedown_active_slot(struct active_request_slot *slot)
 740 {
 741         active_requests--;
 742         slot->in_use = 0;
 743 }
 744
 745 static void release_active_slot(struct active_request_slot *slot)
 746 {
 747         closedown_active_slot(slot);
 748         if (slot->curl && curl_session_count > min_curl_sessions) {
 749 #ifdef USE_CURL_MULTI
 750                 curl_multi_remove_handle(curlm, slot->curl);
 751 #endif
 752                 curl_easy_cleanup(slot->curl);
 753                 slot->curl = NULL;
 754                 curl_session_count--;
 755         }
 756 #ifdef USE_CURL_MULTI
 757         fill_active_slots();
 758 #endif
 759 }
 760
 761 void finish_active_slot(struct active_request_slot *slot)
 762 {
 763         closedown_active_slot(slot);
 764         curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
 765
 766         if (slot->finished != NULL)
 767                 (*slot->finished) = 1;
 768
 769         /* Store slot results so they can be read after the slot is reused */
 770         if (slot->results != NULL) {
 771                 slot->results->curl_result = slot->curl_result;
 772                 slot->results->http_code = slot->http_code;
 773 #if LIBCURL_VERSION_NUM >= 0x070a08
 774                 curl_easy_getinfo(slot->curl, CURLINFO_HTTPAUTH_AVAIL,
 775                                   &slot->results->auth_avail);
 776 #else
 777                 slot->results->auth_avail = 0;
 778 #endif
 779         }
 780
 781         /* Run callback if appropriate */
 782         if (slot->callback_func != NULL)
 783                 slot->callback_func(slot->callback_data);
 784 }
 785
 786 void finish_all_active_slots(void)
 787 {
 788         struct active_request_slot *slot = active_queue_head;
 789
 790         while (slot != NULL)
 791                 if (slot->in_use) {
 792                         run_active_slot(slot);
 793                         slot = active_queue_head;
 794                 } else {
 795                         slot = slot->next;
 796                 }
 797 }
 798
 799 /* Helpers for modifying and creating URLs */
 800 static inline int needs_quote(int ch)
 801 {
 802         if (((ch >= 'A') && (ch <= 'Z'))
 803                         || ((ch >= 'a') && (ch <= 'z'))
 804                         || ((ch >= '0') && (ch <= '9'))
 805                         || (ch == '/')
 806                         || (ch == '-')
 807                         || (ch == '.'))
 808                 return 0;
 809         return 1;
 810 }
 811
 812 static char *quote_ref_url(const char *base, const char *ref)
 813 {
 814         struct strbuf buf = STRBUF_INIT;
 815         const char *cp;
 816         int ch;
 817
 818         end_url_with_slash(&buf, base);
 819
 820         for (cp = ref; (ch = *cp) != 0; cp++)
 821                 if (needs_quote(ch))
 822                         strbuf_addf(&buf, "%%%02x", ch);
 823                 else
 824                         strbuf_addch(&buf, *cp);
 825
 826         return strbuf_detach(&buf, NULL);
 827 }
 828
 829 void append_remote_object_url(struct strbuf *buf, const char *url,
 830                               const char *hex,
 831                               int only_two_digit_prefix)
 832 {
 833         end_url_with_slash(buf, url);
 834
 835         strbuf_addf(buf, "objects/%.*s/", 2, hex);
 836         if (!only_two_digit_prefix)
 837                 strbuf_addf(buf, "%s", hex+2);
 838 }
 839
 840 char *get_remote_object_url(const char *url, const char *hex,
 841                             int only_two_digit_prefix)
 842 {
 843         struct strbuf buf = STRBUF_INIT;
 844         append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
 845         return strbuf_detach(&buf, NULL);
 846 }
 847
 848 int handle_curl_result(struct slot_results *results)
 849 {
 850         /*
 851          * If we see a failing http code with CURLE_OK, we have turned off
 852          * FAILONERROR (to keep the server's custom error response), and should
 853          * translate the code into failure here.
 854          */
 855         if (results->curl_result == CURLE_OK &&
 856             results->http_code >= 400) {
 857                 results->curl_result = CURLE_HTTP_RETURNED_ERROR;
 858                 /*
 859                  * Normally curl will already have put the "reason phrase"
 860                  * from the server into curl_errorstr; unfortunately without
 861                  * FAILONERROR it is lost, so we can give only the numeric
 862                  * status code.
 863                  */
 864                 snprintf(curl_errorstr, sizeof(curl_errorstr),
 865                          "The requested URL returned error: %ld",
 866                          results->http_code);
 867         }
 868
 869         if (results->curl_result == CURLE_OK) {
 870                 credential_approve(&http_auth);
 871                 return HTTP_OK;
 872         } else if (missing_target(results))
 873                 return HTTP_MISSING_TARGET;
 874         else if (results->http_code == 401) {
 875                 if (http_auth.username && http_auth.password) {
 876                         credential_reject(&http_auth);
 877                         return HTTP_NOAUTH;
 878                 } else {
 879                         return HTTP_REAUTH;
 880                 }
 881         } else {
 882 #if LIBCURL_VERSION_NUM >= 0x070c00
 883                 if (!curl_errorstr[0])
 884                         strlcpy(curl_errorstr,
 885                                 curl_easy_strerror(results->curl_result),
 886                                 sizeof(curl_errorstr));
 887 #endif
 888                 return HTTP_ERROR;
 889         }
 890 }
 891
 892 int run_one_slot(struct active_request_slot *slot,
 893                  struct slot_results *results)
 894 {
 895         slot->results = results;
 896         if (!start_active_slot(slot)) {
 897                 snprintf(curl_errorstr, sizeof(curl_errorstr),
 898                          "failed to start HTTP request");
 899                 return HTTP_START_FAILED;
 900         }
 901
 902         run_active_slot(slot);
 903         return handle_curl_result(results);
 904 }
 905
 906 static CURLcode curlinfo_strbuf(CURL *curl, CURLINFO info, struct strbuf *buf)
 907 {
 908         char *ptr;
 909         CURLcode ret;
 910
 911         strbuf_reset(buf);
 912         ret = curl_easy_getinfo(curl, info, &ptr);
 913         if (!ret && ptr)
 914                 strbuf_addstr(buf, ptr);
 915         return ret;
 916 }
 917
 918 /*
 919  * Check for and extract a content-type parameter. "raw"
 920  * should be positioned at the start of the potential
 921  * parameter, with any whitespace already removed.
 922  *
 923  * "name" is the name of the parameter. The value is appended
 924  * to "out".
 925  */
 926 static int extract_param(const char *raw, const char *name,
 927                          struct strbuf *out)
 928 {
 929         size_t len = strlen(name);
 930
 931         if (strncasecmp(raw, name, len))
 932                 return -1;
 933         raw += len;
 934
 935         if (*raw != '=')
 936                 return -1;
 937         raw++;
 938
 939         while (*raw && !isspace(*raw) && *raw != ';')
 940                 strbuf_addch(out, *raw++);
 941         return 0;
 942 }
 943
 944 /*
 945  * Extract a normalized version of the content type, with any
 946  * spaces suppressed, all letters lowercased, and no trailing ";"
 947  * or parameters.
 948  *
 949  * Note that we will silently remove even invalid whitespace. For
 950  * example, "text / plain" is specifically forbidden by RFC 2616,
 951  * but "text/plain" is the only reasonable output, and this keeps
 952  * our code simple.
 953  *
 954  * If the "charset" argument is not NULL, store the value of any
 955  * charset parameter there.
 956  *
 957  * Example:
 958  *   "TEXT/PLAIN; charset=utf-8" -> "text/plain", "utf-8"
 959  *   "text / plain" -> "text/plain"
 960  */
 961 static void extract_content_type(struct strbuf *raw, struct strbuf *type,
 962                                  struct strbuf *charset)
 963 {
 964         const char *p;
 965
 966         strbuf_reset(type);
 967         strbuf_grow(type, raw->len);
 968         for (p = raw->buf; *p; p++) {
 969                 if (isspace(*p))
 970                         continue;
 971                 if (*p == ';') {
 972                         p++;
 973                         break;
 974                 }
 975                 strbuf_addch(type, tolower(*p));
 976         }
 977
 978         if (!charset)
 979                 return;
 980
 981         strbuf_reset(charset);
 982         while (*p) {
 983                 while (isspace(*p) || *p == ';')
 984                         p++;
 985                 if (!extract_param(p, "charset", charset))
 986                         return;
 987                 while (*p && !isspace(*p))
 988                         p++;
 989         }
 990
 991         if (!charset->len && starts_with(type->buf, "text/"))
 992                 strbuf_addstr(charset, "ISO-8859-1");
 993 }
 994
 995 static void write_accept_language(struct strbuf *buf)
 996 {
 997         /*
 998          * MAX_DECIMAL_PLACES must not be larger than 3. If it is larger than
 999          * that, q-value will be smaller than 0.001, the minimum q-value the
1000          * HTTP specification allows. See
1001          * http://tools.ietf.org/html/rfc7231#section-5.3.1 for q-value.
1002          */
1003         const int MAX_DECIMAL_PLACES = 3;
1004         const int MAX_LANGUAGE_TAGS = 1000;
1005         const int MAX_ACCEPT_LANGUAGE_HEADER_SIZE = 4000;
1006         char **language_tags = NULL;
1007         int num_langs = 0;
1008         const char *s = get_preferred_languages();
1009         int i;
1010         struct strbuf tag = STRBUF_INIT;
1011
1012         /* Don't add Accept-Language header if no language is preferred. */
1013         if (!s)
1014                 return;
1015
1016         /*
1017          * Split the colon-separated string of preferred languages into
1018          * language_tags array.
1019          */
1020         do {
1021                 /* collect language tag */
1022                 for (; *s && (isalnum(*s) || *s == '_'); s++)
1023                         strbuf_addch(&tag, *s == '_' ? '-' : *s);
1024
1025                 /* skip .codeset, @modifier and any other unnecessary parts */
1026                 while (*s && *s != ':')
1027                         s++;
1028
1029                 if (tag.len) {
1030                         num_langs++;
1031                         REALLOC_ARRAY(language_tags, num_langs);
1032                         language_tags[num_langs - 1] = strbuf_detach(&tag, NULL);
1033                         if (num_langs >= MAX_LANGUAGE_TAGS - 1) /* -1 for '*' */
1034                                 break;
1035                 }
1036         } while (*s++);
1037
1038         /* write Accept-Language header into buf */
1039         if (num_langs) {
1040                 int last_buf_len = 0;
1041                 int max_q;
1042                 int decimal_places;
1043                 char q_format[32];
1044
1045                 /* add '*' */
1046                 REALLOC_ARRAY(language_tags, num_langs + 1);
1047                 language_tags[num_langs++] = "*"; /* it's OK; this won't be freed */
1048
1049                 /* compute decimal_places */
1050                 for (max_q = 1, decimal_places = 0;
1051                      max_q < num_langs && decimal_places <= MAX_DECIMAL_PLACES;
1052                      decimal_places++, max_q *= 10)
1053                         ;
1054
1055                 sprintf(q_format, ";q=0.%%0%dd", decimal_places);
1056
1057                 strbuf_addstr(buf, "Accept-Language: ");
1058
1059                 for (i = 0; i < num_langs; i++) {
1060                         if (i > 0)
1061                                 strbuf_addstr(buf, ", ");
1062
1063                         strbuf_addstr(buf, language_tags[i]);
1064
1065                         if (i > 0)
1066                                 strbuf_addf(buf, q_format, max_q - i);
1067
1068                         if (buf->len > MAX_ACCEPT_LANGUAGE_HEADER_SIZE) {
1069                                 strbuf_remove(buf, last_buf_len, buf->len - last_buf_len);
1070                                 break;
1071                         }
1072
1073                         last_buf_len = buf->len;
1074                 }
1075         }
1076
1077         /* free language tags -- last one is a static '*' */
1078         for (i = 0; i < num_langs - 1; i++)
1079                 free(language_tags[i]);
1080         free(language_tags);
1081 }
1082
1083 /*
1084  * Get an Accept-Language header which indicates user's preferred languages.
1085  *
1086  * Examples:
1087  *   LANGUAGE= -> ""
1088  *   LANGUAGE=ko:en -> "Accept-Language: ko, en; q=0.9, *; q=0.1"
1089  *   LANGUAGE=ko_KR.UTF-8:sr@latin -> "Accept-Language: ko-KR, sr; q=0.9, *; q=0.1"
1090  *   LANGUAGE=ko LANG=en_US.UTF-8 -> "Accept-Language: ko, *; q=0.1"
1091  *   LANGUAGE= LANG=en_US.UTF-8 -> "Accept-Language: en-US, *; q=0.1"
1092  *   LANGUAGE= LANG=C -> ""
1093  */
1094 static const char *get_accept_language(void)
1095 {
1096         if (!cached_accept_language) {
1097                 struct strbuf buf = STRBUF_INIT;
1098                 write_accept_language(&buf);
1099                 if (buf.len > 0)
1100                         cached_accept_language = strbuf_detach(&buf, NULL);
1101         }
1102
1103         return cached_accept_language;
1104 }
1105
1106 /* http_request() targets */
1107 #define HTTP_REQUEST_STRBUF     0
1108 #define HTTP_REQUEST_FILE       1
1109
1110 static int http_request(const char *url,
1111                         void *result, int target,
1112                         const struct http_get_options *options)
1113 {
1114         struct active_request_slot *slot;
1115         struct slot_results results;
1116         struct curl_slist *headers = NULL;
1117         struct strbuf buf = STRBUF_INIT;
1118         const char *accept_language;
1119         int ret;
1120
1121         slot = get_active_slot();
1122         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1123
1124         if (result == NULL) {
1125                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
1126         } else {
1127                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
1128                 curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
1129
1130                 if (target == HTTP_REQUEST_FILE) {
1131                         long posn = ftell(result);
1132                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1133                                          fwrite);
1134                         if (posn > 0) {
1135                                 strbuf_addf(&buf, "Range: bytes=%ld-", posn);
1136                                 headers = curl_slist_append(headers, buf.buf);
1137                                 strbuf_reset(&buf);
1138                         }
1139                 } else
1140                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1141                                          fwrite_buffer);
1142         }
1143
1144         accept_language = get_accept_language();
1145
1146         if (accept_language)
1147                 headers = curl_slist_append(headers, accept_language);
1148
1149         strbuf_addstr(&buf, "Pragma:");
1150         if (options && options->no_cache)
1151                 strbuf_addstr(&buf, " no-cache");
1152         if (options && options->keep_error)
1153                 curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
1154
1155         headers = curl_slist_append(headers, buf.buf);
1156
1157         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
1158         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
1159         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "gzip");
1160
1161         ret = run_one_slot(slot, &results);
1162
1163         if (options && options->content_type) {
1164                 struct strbuf raw = STRBUF_INIT;
1165                 curlinfo_strbuf(slot->curl, CURLINFO_CONTENT_TYPE, &raw);
1166                 extract_content_type(&raw, options->content_type,
1167                                      options->charset);
1168                 strbuf_release(&raw);
1169         }
1170
1171         if (options && options->effective_url)
1172                 curlinfo_strbuf(slot->curl, CURLINFO_EFFECTIVE_URL,
1173                                 options->effective_url);
1174
1175         curl_slist_free_all(headers);
1176         strbuf_release(&buf);
1177
1178         return ret;
1179 }
1180
1181 /*
1182  * Update the "base" url to a more appropriate value, as deduced by
1183  * redirects seen when requesting a URL starting with "url".
1184  *
1185  * The "asked" parameter is a URL that we asked curl to access, and must begin
1186  * with "base".
1187  *
1188  * The "got" parameter is the URL that curl reported to us as where we ended
1189  * up.
1190  *
1191  * Returns 1 if we updated the base url, 0 otherwise.
1192  *
1193  * Our basic strategy is to compare "base" and "asked" to find the bits
1194  * specific to our request. We then strip those bits off of "got" to yield the
1195  * new base. So for example, if our base is "http://example.com/foo.git",
1196  * and we ask for "http://example.com/foo.git/info/refs", we might end up
1197  * with "https://other.example.com/foo.git/info/refs". We would want the
1198  * new URL to become "https://other.example.com/foo.git".
1199  *
1200  * Note that this assumes a sane redirect scheme. It's entirely possible
1201  * in the example above to end up at a URL that does not even end in
1202  * "info/refs".  In such a case we simply punt, as there is not much we can
1203  * do (and such a scheme is unlikely to represent a real git repository,
1204  * which means we are likely about to abort anyway).
1205  */
1206 static int update_url_from_redirect(struct strbuf *base,
1207                                     const char *asked,
1208                                     const struct strbuf *got)
1209 {
1210         const char *tail;
1211         size_t tail_len;
1212
1213         if (!strcmp(asked, got->buf))
1214                 return 0;
1215
1216         if (!skip_prefix(asked, base->buf, &tail))
1217                 die("BUG: update_url_from_redirect: %s is not a superset of %s",
1218                     asked, base->buf);
1219
1220         tail_len = strlen(tail);
1221
1222         if (got->len < tail_len ||
1223             strcmp(tail, got->buf + got->len - tail_len))
1224                 return 0; /* insane redirect scheme */
1225
1226         strbuf_reset(base);
1227         strbuf_add(base, got->buf, got->len - tail_len);
1228         return 1;
1229 }
1230
1231 static int http_request_reauth(const char *url,
1232                                void *result, int target,
1233                                struct http_get_options *options)
1234 {
1235         int ret = http_request(url, result, target, options);
1236
1237         if (options && options->effective_url && options->base_url) {
1238                 if (update_url_from_redirect(options->base_url,
1239                                              url, options->effective_url)) {
1240                         credential_from_url(&http_auth, options->base_url->buf);
1241                         url = options->effective_url->buf;
1242                 }
1243         }
1244
1245         if (ret != HTTP_REAUTH)
1246                 return ret;
1247
1248         /*
1249          * If we are using KEEP_ERROR, the previous request may have
1250          * put cruft into our output stream; we should clear it out before
1251          * making our next request. We only know how to do this for
1252          * the strbuf case, but that is enough to satisfy current callers.
1253          */
1254         if (options && options->keep_error) {
1255                 switch (target) {
1256                 case HTTP_REQUEST_STRBUF:
1257                         strbuf_reset(result);
1258                         break;
1259                 default:
1260                         die("BUG: HTTP_KEEP_ERROR is only supported with strbufs");
1261                 }
1262         }
1263
1264         credential_fill(&http_auth);
1265
1266         return http_request(url, result, target, options);
1267 }
1268
1269 int http_get_strbuf(const char *url,
1270                     struct strbuf *result,
1271                     struct http_get_options *options)
1272 {
1273         return http_request_reauth(url, result, HTTP_REQUEST_STRBUF, options);
1274 }
1275
1276 /*
1277  * Downloads a URL and stores the result in the given file.
1278  *
1279  * If a previous interrupted download is detected (i.e. a previous temporary
1280  * file is still around) the download is resumed.
1281  */
1282 static int http_get_file(const char *url, const char *filename,
1283                          struct http_get_options *options)
1284 {
1285         int ret;
1286         struct strbuf tmpfile = STRBUF_INIT;
1287         FILE *result;
1288
1289         strbuf_addf(&tmpfile, "%s.temp", filename);
1290         result = fopen(tmpfile.buf, "a");
1291         if (!result) {
1292                 error("Unable to open local file %s", tmpfile.buf);
1293                 ret = HTTP_ERROR;
1294                 goto cleanup;
1295         }
1296
1297         ret = http_request_reauth(url, result, HTTP_REQUEST_FILE, options);
1298         fclose(result);
1299
1300         if (ret == HTTP_OK && move_temp_to_file(tmpfile.buf, filename))
1301                 ret = HTTP_ERROR;
1302 cleanup:
1303         strbuf_release(&tmpfile);
1304         return ret;
1305 }
1306
1307 int http_fetch_ref(const char *base, struct ref *ref)
1308 {
1309         struct http_get_options options = {0};
1310         char *url;
1311         struct strbuf buffer = STRBUF_INIT;
1312         int ret = -1;
1313
1314         options.no_cache = 1;
1315
1316         url = quote_ref_url(base, ref->name);
1317         if (http_get_strbuf(url, &buffer, &options) == HTTP_OK) {
1318                 strbuf_rtrim(&buffer);
1319                 if (buffer.len == 40)
1320                         ret = get_sha1_hex(buffer.buf, ref->old_sha1);
1321                 else if (starts_with(buffer.buf, "ref: ")) {
1322                         ref->symref = xstrdup(buffer.buf + 5);
1323                         ret = 0;
1324                 }
1325         }
1326
1327         strbuf_release(&buffer);
1328         free(url);
1329         return ret;
1330 }
1331
1332 /* Helpers for fetching packs */
1333 static char *fetch_pack_index(unsigned char *sha1, const char *base_url)
1334 {
1335         char *url, *tmp;
1336         struct strbuf buf = STRBUF_INIT;
1337
1338         if (http_is_verbose)
1339                 fprintf(stderr, "Getting index for pack %s\n", sha1_to_hex(sha1));
1340
1341         end_url_with_slash(&buf, base_url);
1342         strbuf_addf(&buf, "objects/pack/pack-%s.idx", sha1_to_hex(sha1));
1343         url = strbuf_detach(&buf, NULL);
1344
1345         strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(sha1));
1346         tmp = strbuf_detach(&buf, NULL);
1347
1348         if (http_get_file(url, tmp, NULL) != HTTP_OK) {
1349                 error("Unable to get pack index %s", url);
1350                 free(tmp);
1351                 tmp = NULL;
1352         }
1353
1354         free(url);
1355         return tmp;
1356 }
1357
1358 static int fetch_and_setup_pack_index(struct packed_git **packs_head,
1359         unsigned char *sha1, const char *base_url)
1360 {
1361         struct packed_git *new_pack;
1362         char *tmp_idx = NULL;
1363         int ret;
1364
1365         if (has_pack_index(sha1)) {
1366                 new_pack = parse_pack_index(sha1, NULL);
1367                 if (!new_pack)
1368                         return -1; /* parse_pack_index() already issued error message */
1369                 goto add_pack;
1370         }
1371
1372         tmp_idx = fetch_pack_index(sha1, base_url);
1373         if (!tmp_idx)
1374                 return -1;
1375
1376         new_pack = parse_pack_index(sha1, tmp_idx);
1377         if (!new_pack) {
1378                 unlink(tmp_idx);
1379                 free(tmp_idx);
1380
1381                 return -1; /* parse_pack_index() already issued error message */
1382         }
1383
1384         ret = verify_pack_index(new_pack);
1385         if (!ret) {
1386                 close_pack_index(new_pack);
1387                 ret = move_temp_to_file(tmp_idx, sha1_pack_index_name(sha1));
1388         }
1389         free(tmp_idx);
1390         if (ret)
1391                 return -1;
1392
1393 add_pack:
1394         new_pack->next = *packs_head;
1395         *packs_head = new_pack;
1396         return 0;
1397 }
1398
1399 int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
1400 {
1401         struct http_get_options options = {0};
1402         int ret = 0, i = 0;
1403         char *url, *data;
1404         struct strbuf buf = STRBUF_INIT;
1405         unsigned char sha1[20];
1406
1407         end_url_with_slash(&buf, base_url);
1408         strbuf_addstr(&buf, "objects/info/packs");
1409         url = strbuf_detach(&buf, NULL);
1410
1411         options.no_cache = 1;
1412         ret = http_get_strbuf(url, &buf, &options);
1413         if (ret != HTTP_OK)
1414                 goto cleanup;
1415
1416         data = buf.buf;
1417         while (i < buf.len) {
1418                 switch (data[i]) {
1419                 case 'P':
1420                         i++;
1421                         if (i + 52 <= buf.len &&
1422                             starts_with(data + i, " pack-") &&
1423                             starts_with(data + i + 46, ".pack\n")) {
1424                                 get_sha1_hex(data + i + 6, sha1);
1425                                 fetch_and_setup_pack_index(packs_head, sha1,
1426                                                       base_url);
1427                                 i += 51;
1428                                 break;
1429                         }
1430                 default:
1431                         while (i < buf.len && data[i] != '\n')
1432                                 i++;
1433                 }
1434                 i++;
1435         }
1436
1437 cleanup:
1438         free(url);
1439         return ret;
1440 }
1441
1442 void release_http_pack_request(struct http_pack_request *preq)
1443 {
1444         if (preq->packfile != NULL) {
1445                 fclose(preq->packfile);
1446                 preq->packfile = NULL;
1447         }
1448         if (preq->range_header != NULL) {
1449                 curl_slist_free_all(preq->range_header);
1450                 preq->range_header = NULL;
1451         }
1452         preq->slot = NULL;
1453         free(preq->url);
1454 }
1455
1456 int finish_http_pack_request(struct http_pack_request *preq)
1457 {
1458         struct packed_git **lst;
1459         struct packed_git *p = preq->target;
1460         char *tmp_idx;
1461         struct child_process ip = CHILD_PROCESS_INIT;
1462         const char *ip_argv[8];
1463
1464         close_pack_index(p);
1465
1466         fclose(preq->packfile);
1467         preq->packfile = NULL;
1468
1469         lst = preq->lst;
1470         while (*lst != p)
1471                 lst = &((*lst)->next);
1472         *lst = (*lst)->next;
1473
1474         tmp_idx = xstrdup(preq->tmpfile);
1475         strcpy(tmp_idx + strlen(tmp_idx) - strlen(".pack.temp"),
1476                ".idx.temp");
1477
1478         ip_argv[0] = "index-pack";
1479         ip_argv[1] = "-o";
1480         ip_argv[2] = tmp_idx;
1481         ip_argv[3] = preq->tmpfile;
1482         ip_argv[4] = NULL;
1483
1484         ip.argv = ip_argv;
1485         ip.git_cmd = 1;
1486         ip.no_stdin = 1;
1487         ip.no_stdout = 1;
1488
1489         if (run_command(&ip)) {
1490                 unlink(preq->tmpfile);
1491                 unlink(tmp_idx);
1492                 free(tmp_idx);
1493                 return -1;
1494         }
1495
1496         unlink(sha1_pack_index_name(p->sha1));
1497
1498         if (move_temp_to_file(preq->tmpfile, sha1_pack_name(p->sha1))
1499          || move_temp_to_file(tmp_idx, sha1_pack_index_name(p->sha1))) {
1500                 free(tmp_idx);
1501                 return -1;
1502         }
1503
1504         install_packed_git(p);
1505         free(tmp_idx);
1506         return 0;
1507 }
1508
1509 struct http_pack_request *new_http_pack_request(
1510         struct packed_git *target, const char *base_url)
1511 {
1512         long prev_posn = 0;
1513         char range[RANGE_HEADER_SIZE];
1514         struct strbuf buf = STRBUF_INIT;
1515         struct http_pack_request *preq;
1516
1517         preq = xcalloc(1, sizeof(*preq));
1518         preq->target = target;
1519
1520         end_url_with_slash(&buf, base_url);
1521         strbuf_addf(&buf, "objects/pack/pack-%s.pack",
1522                 sha1_to_hex(target->sha1));
1523         preq->url = strbuf_detach(&buf, NULL);
1524
1525         snprintf(preq->tmpfile, sizeof(preq->tmpfile), "%s.temp",
1526                 sha1_pack_name(target->sha1));
1527         preq->packfile = fopen(preq->tmpfile, "a");
1528         if (!preq->packfile) {
1529                 error("Unable to open local file %s for pack",
1530                       preq->tmpfile);
1531                 goto abort;
1532         }
1533
1534         preq->slot = get_active_slot();
1535         curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
1536         curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
1537         curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
1538         curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1539                 no_pragma_header);
1540
1541         /*
1542          * If there is data present from a previous transfer attempt,
1543          * resume where it left off
1544          */
1545         prev_posn = ftell(preq->packfile);
1546         if (prev_posn>0) {
1547                 if (http_is_verbose)
1548                         fprintf(stderr,
1549                                 "Resuming fetch of pack %s at byte %ld\n",
1550                                 sha1_to_hex(target->sha1), prev_posn);
1551                 sprintf(range, "Range: bytes=%ld-", prev_posn);
1552                 preq->range_header = curl_slist_append(NULL, range);
1553                 curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1554                         preq->range_header);
1555         }
1556
1557         return preq;
1558
1559 abort:
1560         free(preq->url);
1561         free(preq);
1562         return NULL;
1563 }
1564
1565 /* Helpers for fetching objects (loose) */
1566 static size_t fwrite_sha1_file(char *ptr, size_t eltsize, size_t nmemb,
1567                                void *data)
1568 {
1569         unsigned char expn[4096];
1570         size_t size = eltsize * nmemb;
1571         int posn = 0;
1572         struct http_object_request *freq =
1573                 (struct http_object_request *)data;
1574         do {
1575                 ssize_t retval = xwrite(freq->localfile,
1576                                         (char *) ptr + posn, size - posn);
1577                 if (retval < 0)
1578                         return posn;
1579                 posn += retval;
1580         } while (posn < size);
1581
1582         freq->stream.avail_in = size;
1583         freq->stream.next_in = (void *)ptr;
1584         do {
1585                 freq->stream.next_out = expn;
1586                 freq->stream.avail_out = sizeof(expn);
1587                 freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
1588                 git_SHA1_Update(&freq->c, expn,
1589                                 sizeof(expn) - freq->stream.avail_out);
1590         } while (freq->stream.avail_in && freq->zret == Z_OK);
1591         return size;
1592 }
1593
1594 struct http_object_request *new_http_object_request(const char *base_url,
1595         unsigned char *sha1)
1596 {
1597         char *hex = sha1_to_hex(sha1);
1598         const char *filename;
1599         char prevfile[PATH_MAX];
1600         int prevlocal;
1601         char prev_buf[PREV_BUF_SIZE];
1602         ssize_t prev_read = 0;
1603         long prev_posn = 0;
1604         char range[RANGE_HEADER_SIZE];
1605         struct curl_slist *range_header = NULL;
1606         struct http_object_request *freq;
1607
1608         freq = xcalloc(1, sizeof(*freq));
1609         hashcpy(freq->sha1, sha1);
1610         freq->localfile = -1;
1611
1612         filename = sha1_file_name(sha1);
1613         snprintf(freq->tmpfile, sizeof(freq->tmpfile),
1614                  "%s.temp", filename);
1615
1616         snprintf(prevfile, sizeof(prevfile), "%s.prev", filename);
1617         unlink_or_warn(prevfile);
1618         rename(freq->tmpfile, prevfile);
1619         unlink_or_warn(freq->tmpfile);
1620
1621         if (freq->localfile != -1)
1622                 error("fd leakage in start: %d", freq->localfile);
1623         freq->localfile = open(freq->tmpfile,
1624                                O_WRONLY | O_CREAT | O_EXCL, 0666);
1625         /*
1626          * This could have failed due to the "lazy directory creation";
1627          * try to mkdir the last path component.
1628          */
1629         if (freq->localfile < 0 && errno == ENOENT) {
1630                 char *dir = strrchr(freq->tmpfile, '/');
1631                 if (dir) {
1632                         *dir = 0;
1633                         mkdir(freq->tmpfile, 0777);
1634                         *dir = '/';
1635                 }
1636                 freq->localfile = open(freq->tmpfile,
1637                                        O_WRONLY | O_CREAT | O_EXCL, 0666);
1638         }
1639
1640         if (freq->localfile < 0) {
1641                 error("Couldn't create temporary file %s: %s",
1642                       freq->tmpfile, strerror(errno));
1643                 goto abort;
1644         }
1645
1646         git_inflate_init(&freq->stream);
1647
1648         git_SHA1_Init(&freq->c);
1649
1650         freq->url = get_remote_object_url(base_url, hex, 0);
1651
1652         /*
1653          * If a previous temp file is present, process what was already
1654          * fetched.
1655          */
1656         prevlocal = open(prevfile, O_RDONLY);
1657         if (prevlocal != -1) {
1658                 do {
1659                         prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
1660                         if (prev_read>0) {
1661                                 if (fwrite_sha1_file(prev_buf,
1662                                                      1,
1663                                                      prev_read,
1664                                                      freq) == prev_read) {
1665                                         prev_posn += prev_read;
1666                                 } else {
1667                                         prev_read = -1;
1668                                 }
1669                         }
1670                 } while (prev_read > 0);
1671                 close(prevlocal);
1672         }
1673         unlink_or_warn(prevfile);
1674
1675         /*
1676          * Reset inflate/SHA1 if there was an error reading the previous temp
1677          * file; also rewind to the beginning of the local file.
1678          */
1679         if (prev_read == -1) {
1680                 memset(&freq->stream, 0, sizeof(freq->stream));
1681                 git_inflate_init(&freq->stream);
1682                 git_SHA1_Init(&freq->c);
1683                 if (prev_posn>0) {
1684                         prev_posn = 0;
1685                         lseek(freq->localfile, 0, SEEK_SET);
1686                         if (ftruncate(freq->localfile, 0) < 0) {
1687                                 error("Couldn't truncate temporary file %s: %s",
1688                                           freq->tmpfile, strerror(errno));
1689                                 goto abort;
1690                         }
1691                 }
1692         }
1693
1694         freq->slot = get_active_slot();
1695
1696         curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
1697         curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
1698         curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
1699         curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
1700         curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
1701
1702         /*
1703          * If we have successfully processed data from a previous fetch
1704          * attempt, only fetch the data we don't already have.
1705          */
1706         if (prev_posn>0) {
1707                 if (http_is_verbose)
1708                         fprintf(stderr,
1709                                 "Resuming fetch of object %s at byte %ld\n",
1710                                 hex, prev_posn);
1711                 sprintf(range, "Range: bytes=%ld-", prev_posn);
1712                 range_header = curl_slist_append(range_header, range);
1713                 curl_easy_setopt(freq->slot->curl,
1714                                  CURLOPT_HTTPHEADER, range_header);
1715         }
1716
1717         return freq;
1718
1719 abort:
1720         free(freq->url);
1721         free(freq);
1722         return NULL;
1723 }
1724
1725 void process_http_object_request(struct http_object_request *freq)
1726 {
1727         if (freq->slot == NULL)
1728                 return;
1729         freq->curl_result = freq->slot->curl_result;
1730         freq->http_code = freq->slot->http_code;
1731         freq->slot = NULL;
1732 }
1733
1734 int finish_http_object_request(struct http_object_request *freq)
1735 {
1736         struct stat st;
1737
1738         close(freq->localfile);
1739         freq->localfile = -1;
1740
1741         process_http_object_request(freq);
1742
1743         if (freq->http_code == 416) {
1744                 warning("requested range invalid; we may already have all the data.");
1745         } else if (freq->curl_result != CURLE_OK) {
1746                 if (stat(freq->tmpfile, &st) == 0)
1747                         if (st.st_size == 0)
1748                                 unlink_or_warn(freq->tmpfile);
1749                 return -1;
1750         }
1751
1752         git_inflate_end(&freq->stream);
1753         git_SHA1_Final(freq->real_sha1, &freq->c);
1754         if (freq->zret != Z_STREAM_END) {
1755                 unlink_or_warn(freq->tmpfile);
1756                 return -1;
1757         }
1758         if (hashcmp(freq->sha1, freq->real_sha1)) {
1759                 unlink_or_warn(freq->tmpfile);
1760                 return -1;
1761         }
1762         freq->rename =
1763                 move_temp_to_file(freq->tmpfile, sha1_file_name(freq->sha1));
1764
1765         return freq->rename;
1766 }
1767
1768 void abort_http_object_request(struct http_object_request *freq)
1769 {
1770         unlink_or_warn(freq->tmpfile);
1771
1772         release_http_object_request(freq);
1773 }
1774
1775 void release_http_object_request(struct http_object_request *freq)
1776 {
1777         if (freq->localfile != -1) {
1778                 close(freq->localfile);
1779                 freq->localfile = -1;
1780         }
1781         if (freq->url != NULL) {
1782                 free(freq->url);
1783                 freq->url = NULL;
1784         }
1785         if (freq->slot != NULL) {
1786                 freq->slot->callback_func = NULL;
1787                 freq->slot->callback_data = NULL;
1788                 release_active_slot(freq->slot);
1789                 freq->slot = NULL;
1790         }
1791 }