http.con commit Merge branch 'jc/doc-commit-only' (0cfd333)
   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
  12int active_requests;
  13int http_is_verbose;
  14size_t http_post_buffer = 16 * LARGE_PACKET_MAX;
  15
  16#if LIBCURL_VERSION_NUM >= 0x070a06
  17#define LIBCURL_CAN_HANDLE_AUTH_ANY
  18#endif
  19
  20static int min_curl_sessions = 1;
  21static int curl_session_count;
  22#ifdef USE_CURL_MULTI
  23static int max_requests = -1;
  24static CURLM *curlm;
  25#endif
  26#ifndef NO_CURL_EASY_DUPHANDLE
  27static CURL *curl_default;
  28#endif
  29
  30#define PREV_BUF_SIZE 4096
  31#define RANGE_HEADER_SIZE 30
  32
  33char curl_errorstr[CURL_ERROR_SIZE];
  34
  35static int curl_ssl_verify = -1;
  36static int curl_ssl_try;
  37static const char *ssl_cert;
  38#if LIBCURL_VERSION_NUM >= 0x070903
  39static const char *ssl_key;
  40#endif
  41#if LIBCURL_VERSION_NUM >= 0x070908
  42static const char *ssl_capath;
  43#endif
  44static const char *ssl_cainfo;
  45static long curl_low_speed_limit = -1;
  46static long curl_low_speed_time = -1;
  47static int curl_ftp_no_epsv;
  48static const char *curl_http_proxy;
  49static const char *curl_cookie_file;
  50static int curl_save_cookies;
  51struct credential http_auth = CREDENTIAL_INIT;
  52static int http_proactive_auth;
  53static const char *user_agent;
  54
  55#if LIBCURL_VERSION_NUM >= 0x071700
  56/* Use CURLOPT_KEYPASSWD as is */
  57#elif LIBCURL_VERSION_NUM >= 0x070903
  58#define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
  59#else
  60#define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
  61#endif
  62
  63static struct credential cert_auth = CREDENTIAL_INIT;
  64static int ssl_cert_password_required;
  65
  66static struct curl_slist *pragma_header;
  67static struct curl_slist *no_pragma_header;
  68
  69static struct active_request_slot *active_queue_head;
  70
  71size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
  72{
  73        size_t size = eltsize * nmemb;
  74        struct buffer *buffer = buffer_;
  75
  76        if (size > buffer->buf.len - buffer->posn)
  77                size = buffer->buf.len - buffer->posn;
  78        memcpy(ptr, buffer->buf.buf + buffer->posn, size);
  79        buffer->posn += size;
  80
  81        return size;
  82}
  83
  84#ifndef NO_CURL_IOCTL
  85curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
  86{
  87        struct buffer *buffer = clientp;
  88
  89        switch (cmd) {
  90        case CURLIOCMD_NOP:
  91                return CURLIOE_OK;
  92
  93        case CURLIOCMD_RESTARTREAD:
  94                buffer->posn = 0;
  95                return CURLIOE_OK;
  96
  97        default:
  98                return CURLIOE_UNKNOWNCMD;
  99        }
 100}
 101#endif
 102
 103size_t fwrite_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
 104{
 105        size_t size = eltsize * nmemb;
 106        struct strbuf *buffer = buffer_;
 107
 108        strbuf_add(buffer, ptr, size);
 109        return size;
 110}
 111
 112size_t fwrite_null(char *ptr, size_t eltsize, size_t nmemb, void *strbuf)
 113{
 114        return eltsize * nmemb;
 115}
 116
 117#ifdef USE_CURL_MULTI
 118static void process_curl_messages(void)
 119{
 120        int num_messages;
 121        struct active_request_slot *slot;
 122        CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
 123
 124        while (curl_message != NULL) {
 125                if (curl_message->msg == CURLMSG_DONE) {
 126                        int curl_result = curl_message->data.result;
 127                        slot = active_queue_head;
 128                        while (slot != NULL &&
 129                               slot->curl != curl_message->easy_handle)
 130                                slot = slot->next;
 131                        if (slot != NULL) {
 132                                curl_multi_remove_handle(curlm, slot->curl);
 133                                slot->curl_result = curl_result;
 134                                finish_active_slot(slot);
 135                        } else {
 136                                fprintf(stderr, "Received DONE message for unknown request!\n");
 137                        }
 138                } else {
 139                        fprintf(stderr, "Unknown CURL message received: %d\n",
 140                                (int)curl_message->msg);
 141                }
 142                curl_message = curl_multi_info_read(curlm, &num_messages);
 143        }
 144}
 145#endif
 146
 147static int http_options(const char *var, const char *value, void *cb)
 148{
 149        if (!strcmp("http.sslverify", var)) {
 150                curl_ssl_verify = git_config_bool(var, value);
 151                return 0;
 152        }
 153        if (!strcmp("http.sslcert", var))
 154                return git_config_string(&ssl_cert, var, value);
 155#if LIBCURL_VERSION_NUM >= 0x070903
 156        if (!strcmp("http.sslkey", var))
 157                return git_config_string(&ssl_key, var, value);
 158#endif
 159#if LIBCURL_VERSION_NUM >= 0x070908
 160        if (!strcmp("http.sslcapath", var))
 161                return git_config_string(&ssl_capath, var, value);
 162#endif
 163        if (!strcmp("http.sslcainfo", var))
 164                return git_config_string(&ssl_cainfo, var, value);
 165        if (!strcmp("http.sslcertpasswordprotected", var)) {
 166                ssl_cert_password_required = git_config_bool(var, value);
 167                return 0;
 168        }
 169        if (!strcmp("http.ssltry", var)) {
 170                curl_ssl_try = git_config_bool(var, value);
 171                return 0;
 172        }
 173        if (!strcmp("http.minsessions", var)) {
 174                min_curl_sessions = git_config_int(var, value);
 175#ifndef USE_CURL_MULTI
 176                if (min_curl_sessions > 1)
 177                        min_curl_sessions = 1;
 178#endif
 179                return 0;
 180        }
 181#ifdef USE_CURL_MULTI
 182        if (!strcmp("http.maxrequests", var)) {
 183                max_requests = git_config_int(var, value);
 184                return 0;
 185        }
 186#endif
 187        if (!strcmp("http.lowspeedlimit", var)) {
 188                curl_low_speed_limit = (long)git_config_int(var, value);
 189                return 0;
 190        }
 191        if (!strcmp("http.lowspeedtime", var)) {
 192                curl_low_speed_time = (long)git_config_int(var, value);
 193                return 0;
 194        }
 195
 196        if (!strcmp("http.noepsv", var)) {
 197                curl_ftp_no_epsv = git_config_bool(var, value);
 198                return 0;
 199        }
 200        if (!strcmp("http.proxy", var))
 201                return git_config_string(&curl_http_proxy, var, value);
 202
 203        if (!strcmp("http.cookiefile", var))
 204                return git_config_string(&curl_cookie_file, var, value);
 205        if (!strcmp("http.savecookies", var)) {
 206                curl_save_cookies = git_config_bool(var, value);
 207                return 0;
 208        }
 209
 210        if (!strcmp("http.postbuffer", var)) {
 211                http_post_buffer = git_config_int(var, value);
 212                if (http_post_buffer < LARGE_PACKET_MAX)
 213                        http_post_buffer = LARGE_PACKET_MAX;
 214                return 0;
 215        }
 216
 217        if (!strcmp("http.useragent", var))
 218                return git_config_string(&user_agent, var, value);
 219
 220        /* Fall back on the default ones */
 221        return git_default_config(var, value, cb);
 222}
 223
 224static void init_curl_http_auth(CURL *result)
 225{
 226        if (!http_auth.username)
 227                return;
 228
 229        credential_fill(&http_auth);
 230
 231#if LIBCURL_VERSION_NUM >= 0x071301
 232        curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username);
 233        curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password);
 234#else
 235        {
 236                static struct strbuf up = STRBUF_INIT;
 237                /*
 238                 * Note that we assume we only ever have a single set of
 239                 * credentials in a given program run, so we do not have
 240                 * to worry about updating this buffer, only setting its
 241                 * initial value.
 242                 */
 243                if (!up.len)
 244                        strbuf_addf(&up, "%s:%s",
 245                                http_auth.username, http_auth.password);
 246                curl_easy_setopt(result, CURLOPT_USERPWD, up.buf);
 247        }
 248#endif
 249}
 250
 251static int has_cert_password(void)
 252{
 253        if (ssl_cert == NULL || ssl_cert_password_required != 1)
 254                return 0;
 255        if (!cert_auth.password) {
 256                cert_auth.protocol = xstrdup("cert");
 257                cert_auth.username = xstrdup("");
 258                cert_auth.path = xstrdup(ssl_cert);
 259                credential_fill(&cert_auth);
 260        }
 261        return 1;
 262}
 263
 264#if LIBCURL_VERSION_NUM >= 0x071900
 265static void set_curl_keepalive(CURL *c)
 266{
 267        curl_easy_setopt(c, CURLOPT_TCP_KEEPALIVE, 1);
 268}
 269
 270#elif LIBCURL_VERSION_NUM >= 0x071000
 271static int sockopt_callback(void *client, curl_socket_t fd, curlsocktype type)
 272{
 273        int ka = 1;
 274        int rc;
 275        socklen_t len = (socklen_t)sizeof(ka);
 276
 277        if (type != CURLSOCKTYPE_IPCXN)
 278                return 0;
 279
 280        rc = setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&ka, len);
 281        if (rc < 0)
 282                warning("unable to set SO_KEEPALIVE on socket %s",
 283                        strerror(errno));
 284
 285        return 0; /* CURL_SOCKOPT_OK only exists since curl 7.21.5 */
 286}
 287
 288static void set_curl_keepalive(CURL *c)
 289{
 290        curl_easy_setopt(c, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
 291}
 292
 293#else
 294static void set_curl_keepalive(CURL *c)
 295{
 296        /* not supported on older curl versions */
 297}
 298#endif
 299
 300static CURL *get_curl_handle(void)
 301{
 302        CURL *result = curl_easy_init();
 303
 304        if (!result)
 305                die("curl_easy_init failed");
 306
 307        if (!curl_ssl_verify) {
 308                curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
 309                curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
 310        } else {
 311                /* Verify authenticity of the peer's certificate */
 312                curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
 313                /* The name in the cert must match whom we tried to connect */
 314                curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
 315        }
 316
 317#if LIBCURL_VERSION_NUM >= 0x070907
 318        curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
 319#endif
 320#ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 321        curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 322#endif
 323
 324        if (http_proactive_auth)
 325                init_curl_http_auth(result);
 326
 327        if (ssl_cert != NULL)
 328                curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
 329        if (has_cert_password())
 330                curl_easy_setopt(result, CURLOPT_KEYPASSWD, cert_auth.password);
 331#if LIBCURL_VERSION_NUM >= 0x070903
 332        if (ssl_key != NULL)
 333                curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
 334#endif
 335#if LIBCURL_VERSION_NUM >= 0x070908
 336        if (ssl_capath != NULL)
 337                curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
 338#endif
 339        if (ssl_cainfo != NULL)
 340                curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
 341
 342        if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
 343                curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
 344                                 curl_low_speed_limit);
 345                curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
 346                                 curl_low_speed_time);
 347        }
 348
 349        curl_easy_setopt(result, CURLOPT_FOLLOWLOCATION, 1);
 350#if LIBCURL_VERSION_NUM >= 0x071301
 351        curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
 352#elif LIBCURL_VERSION_NUM >= 0x071101
 353        curl_easy_setopt(result, CURLOPT_POST301, 1);
 354#endif
 355
 356        if (getenv("GIT_CURL_VERBOSE"))
 357                curl_easy_setopt(result, CURLOPT_VERBOSE, 1);
 358
 359        curl_easy_setopt(result, CURLOPT_USERAGENT,
 360                user_agent ? user_agent : git_user_agent());
 361
 362        if (curl_ftp_no_epsv)
 363                curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
 364
 365#ifdef CURLOPT_USE_SSL
 366        if (curl_ssl_try)
 367                curl_easy_setopt(result, CURLOPT_USE_SSL, CURLUSESSL_TRY);
 368#endif
 369
 370        if (curl_http_proxy) {
 371                curl_easy_setopt(result, CURLOPT_PROXY, curl_http_proxy);
 372                curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 373        }
 374
 375        set_curl_keepalive(result);
 376
 377        return result;
 378}
 379
 380static void set_from_env(const char **var, const char *envname)
 381{
 382        const char *val = getenv(envname);
 383        if (val)
 384                *var = val;
 385}
 386
 387void http_init(struct remote *remote, const char *url, int proactive_auth)
 388{
 389        char *low_speed_limit;
 390        char *low_speed_time;
 391        char *normalized_url;
 392        struct urlmatch_config config = { STRING_LIST_INIT_DUP };
 393
 394        config.section = "http";
 395        config.key = NULL;
 396        config.collect_fn = http_options;
 397        config.cascade_fn = git_default_config;
 398        config.cb = NULL;
 399
 400        http_is_verbose = 0;
 401        normalized_url = url_normalize(url, &config.url);
 402
 403        git_config(urlmatch_config_entry, &config);
 404        free(normalized_url);
 405
 406        if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK)
 407                die("curl_global_init failed");
 408
 409        http_proactive_auth = proactive_auth;
 410
 411        if (remote && remote->http_proxy)
 412                curl_http_proxy = xstrdup(remote->http_proxy);
 413
 414        pragma_header = curl_slist_append(pragma_header, "Pragma: no-cache");
 415        no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
 416
 417#ifdef USE_CURL_MULTI
 418        {
 419                char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
 420                if (http_max_requests != NULL)
 421                        max_requests = atoi(http_max_requests);
 422        }
 423
 424        curlm = curl_multi_init();
 425        if (!curlm)
 426                die("curl_multi_init failed");
 427#endif
 428
 429        if (getenv("GIT_SSL_NO_VERIFY"))
 430                curl_ssl_verify = 0;
 431
 432        set_from_env(&ssl_cert, "GIT_SSL_CERT");
 433#if LIBCURL_VERSION_NUM >= 0x070903
 434        set_from_env(&ssl_key, "GIT_SSL_KEY");
 435#endif
 436#if LIBCURL_VERSION_NUM >= 0x070908
 437        set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
 438#endif
 439        set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
 440
 441        set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
 442
 443        low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
 444        if (low_speed_limit != NULL)
 445                curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
 446        low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
 447        if (low_speed_time != NULL)
 448                curl_low_speed_time = strtol(low_speed_time, NULL, 10);
 449
 450        if (curl_ssl_verify == -1)
 451                curl_ssl_verify = 1;
 452
 453        curl_session_count = 0;
 454#ifdef USE_CURL_MULTI
 455        if (max_requests < 1)
 456                max_requests = DEFAULT_MAX_REQUESTS;
 457#endif
 458
 459        if (getenv("GIT_CURL_FTP_NO_EPSV"))
 460                curl_ftp_no_epsv = 1;
 461
 462        if (url) {
 463                credential_from_url(&http_auth, url);
 464                if (!ssl_cert_password_required &&
 465                    getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
 466                    starts_with(url, "https://"))
 467                        ssl_cert_password_required = 1;
 468        }
 469
 470#ifndef NO_CURL_EASY_DUPHANDLE
 471        curl_default = get_curl_handle();
 472#endif
 473}
 474
 475void http_cleanup(void)
 476{
 477        struct active_request_slot *slot = active_queue_head;
 478
 479        while (slot != NULL) {
 480                struct active_request_slot *next = slot->next;
 481                if (slot->curl != NULL) {
 482#ifdef USE_CURL_MULTI
 483                        curl_multi_remove_handle(curlm, slot->curl);
 484#endif
 485                        curl_easy_cleanup(slot->curl);
 486                }
 487                free(slot);
 488                slot = next;
 489        }
 490        active_queue_head = NULL;
 491
 492#ifndef NO_CURL_EASY_DUPHANDLE
 493        curl_easy_cleanup(curl_default);
 494#endif
 495
 496#ifdef USE_CURL_MULTI
 497        curl_multi_cleanup(curlm);
 498#endif
 499        curl_global_cleanup();
 500
 501        curl_slist_free_all(pragma_header);
 502        pragma_header = NULL;
 503
 504        curl_slist_free_all(no_pragma_header);
 505        no_pragma_header = NULL;
 506
 507        if (curl_http_proxy) {
 508                free((void *)curl_http_proxy);
 509                curl_http_proxy = NULL;
 510        }
 511
 512        if (cert_auth.password != NULL) {
 513                memset(cert_auth.password, 0, strlen(cert_auth.password));
 514                free(cert_auth.password);
 515                cert_auth.password = NULL;
 516        }
 517        ssl_cert_password_required = 0;
 518}
 519
 520struct active_request_slot *get_active_slot(void)
 521{
 522        struct active_request_slot *slot = active_queue_head;
 523        struct active_request_slot *newslot;
 524
 525#ifdef USE_CURL_MULTI
 526        int num_transfers;
 527
 528        /* Wait for a slot to open up if the queue is full */
 529        while (active_requests >= max_requests) {
 530                curl_multi_perform(curlm, &num_transfers);
 531                if (num_transfers < active_requests)
 532                        process_curl_messages();
 533        }
 534#endif
 535
 536        while (slot != NULL && slot->in_use)
 537                slot = slot->next;
 538
 539        if (slot == NULL) {
 540                newslot = xmalloc(sizeof(*newslot));
 541                newslot->curl = NULL;
 542                newslot->in_use = 0;
 543                newslot->next = NULL;
 544
 545                slot = active_queue_head;
 546                if (slot == NULL) {
 547                        active_queue_head = newslot;
 548                } else {
 549                        while (slot->next != NULL)
 550                                slot = slot->next;
 551                        slot->next = newslot;
 552                }
 553                slot = newslot;
 554        }
 555
 556        if (slot->curl == NULL) {
 557#ifdef NO_CURL_EASY_DUPHANDLE
 558                slot->curl = get_curl_handle();
 559#else
 560                slot->curl = curl_easy_duphandle(curl_default);
 561#endif
 562                curl_session_count++;
 563        }
 564
 565        active_requests++;
 566        slot->in_use = 1;
 567        slot->results = NULL;
 568        slot->finished = NULL;
 569        slot->callback_data = NULL;
 570        slot->callback_func = NULL;
 571        curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
 572        if (curl_save_cookies)
 573                curl_easy_setopt(slot->curl, CURLOPT_COOKIEJAR, curl_cookie_file);
 574        curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
 575        curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
 576        curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
 577        curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
 578        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
 579        curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
 580        curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
 581        curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 582        curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 1);
 583        if (http_auth.password)
 584                init_curl_http_auth(slot->curl);
 585
 586        return slot;
 587}
 588
 589int start_active_slot(struct active_request_slot *slot)
 590{
 591#ifdef USE_CURL_MULTI
 592        CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
 593        int num_transfers;
 594
 595        if (curlm_result != CURLM_OK &&
 596            curlm_result != CURLM_CALL_MULTI_PERFORM) {
 597                active_requests--;
 598                slot->in_use = 0;
 599                return 0;
 600        }
 601
 602        /*
 603         * We know there must be something to do, since we just added
 604         * something.
 605         */
 606        curl_multi_perform(curlm, &num_transfers);
 607#endif
 608        return 1;
 609}
 610
 611#ifdef USE_CURL_MULTI
 612struct fill_chain {
 613        void *data;
 614        int (*fill)(void *);
 615        struct fill_chain *next;
 616};
 617
 618static struct fill_chain *fill_cfg;
 619
 620void add_fill_function(void *data, int (*fill)(void *))
 621{
 622        struct fill_chain *new = xmalloc(sizeof(*new));
 623        struct fill_chain **linkp = &fill_cfg;
 624        new->data = data;
 625        new->fill = fill;
 626        new->next = NULL;
 627        while (*linkp)
 628                linkp = &(*linkp)->next;
 629        *linkp = new;
 630}
 631
 632void fill_active_slots(void)
 633{
 634        struct active_request_slot *slot = active_queue_head;
 635
 636        while (active_requests < max_requests) {
 637                struct fill_chain *fill;
 638                for (fill = fill_cfg; fill; fill = fill->next)
 639                        if (fill->fill(fill->data))
 640                                break;
 641
 642                if (!fill)
 643                        break;
 644        }
 645
 646        while (slot != NULL) {
 647                if (!slot->in_use && slot->curl != NULL
 648                        && curl_session_count > min_curl_sessions) {
 649                        curl_easy_cleanup(slot->curl);
 650                        slot->curl = NULL;
 651                        curl_session_count--;
 652                }
 653                slot = slot->next;
 654        }
 655}
 656
 657void step_active_slots(void)
 658{
 659        int num_transfers;
 660        CURLMcode curlm_result;
 661
 662        do {
 663                curlm_result = curl_multi_perform(curlm, &num_transfers);
 664        } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
 665        if (num_transfers < active_requests) {
 666                process_curl_messages();
 667                fill_active_slots();
 668        }
 669}
 670#endif
 671
 672void run_active_slot(struct active_request_slot *slot)
 673{
 674#ifdef USE_CURL_MULTI
 675        fd_set readfds;
 676        fd_set writefds;
 677        fd_set excfds;
 678        int max_fd;
 679        struct timeval select_timeout;
 680        int finished = 0;
 681
 682        slot->finished = &finished;
 683        while (!finished) {
 684                step_active_slots();
 685
 686                if (slot->in_use) {
 687#if LIBCURL_VERSION_NUM >= 0x070f04
 688                        long curl_timeout;
 689                        curl_multi_timeout(curlm, &curl_timeout);
 690                        if (curl_timeout == 0) {
 691                                continue;
 692                        } else if (curl_timeout == -1) {
 693                                select_timeout.tv_sec  = 0;
 694                                select_timeout.tv_usec = 50000;
 695                        } else {
 696                                select_timeout.tv_sec  =  curl_timeout / 1000;
 697                                select_timeout.tv_usec = (curl_timeout % 1000) * 1000;
 698                        }
 699#else
 700                        select_timeout.tv_sec  = 0;
 701                        select_timeout.tv_usec = 50000;
 702#endif
 703
 704                        max_fd = -1;
 705                        FD_ZERO(&readfds);
 706                        FD_ZERO(&writefds);
 707                        FD_ZERO(&excfds);
 708                        curl_multi_fdset(curlm, &readfds, &writefds, &excfds, &max_fd);
 709
 710                        /*
 711                         * It can happen that curl_multi_timeout returns a pathologically
 712                         * long timeout when curl_multi_fdset returns no file descriptors
 713                         * to read.  See commit message for more details.
 714                         */
 715                        if (max_fd < 0 &&
 716                            (select_timeout.tv_sec > 0 ||
 717                             select_timeout.tv_usec > 50000)) {
 718                                select_timeout.tv_sec  = 0;
 719                                select_timeout.tv_usec = 50000;
 720                        }
 721
 722                        select(max_fd+1, &readfds, &writefds, &excfds, &select_timeout);
 723                }
 724        }
 725#else
 726        while (slot->in_use) {
 727                slot->curl_result = curl_easy_perform(slot->curl);
 728                finish_active_slot(slot);
 729        }
 730#endif
 731}
 732
 733static void closedown_active_slot(struct active_request_slot *slot)
 734{
 735        active_requests--;
 736        slot->in_use = 0;
 737}
 738
 739static void release_active_slot(struct active_request_slot *slot)
 740{
 741        closedown_active_slot(slot);
 742        if (slot->curl && curl_session_count > min_curl_sessions) {
 743#ifdef USE_CURL_MULTI
 744                curl_multi_remove_handle(curlm, slot->curl);
 745#endif
 746                curl_easy_cleanup(slot->curl);
 747                slot->curl = NULL;
 748                curl_session_count--;
 749        }
 750#ifdef USE_CURL_MULTI
 751        fill_active_slots();
 752#endif
 753}
 754
 755void finish_active_slot(struct active_request_slot *slot)
 756{
 757        closedown_active_slot(slot);
 758        curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
 759
 760        if (slot->finished != NULL)
 761                (*slot->finished) = 1;
 762
 763        /* Store slot results so they can be read after the slot is reused */
 764        if (slot->results != NULL) {
 765                slot->results->curl_result = slot->curl_result;
 766                slot->results->http_code = slot->http_code;
 767#if LIBCURL_VERSION_NUM >= 0x070a08
 768                curl_easy_getinfo(slot->curl, CURLINFO_HTTPAUTH_AVAIL,
 769                                  &slot->results->auth_avail);
 770#else
 771                slot->results->auth_avail = 0;
 772#endif
 773        }
 774
 775        /* Run callback if appropriate */
 776        if (slot->callback_func != NULL)
 777                slot->callback_func(slot->callback_data);
 778}
 779
 780void finish_all_active_slots(void)
 781{
 782        struct active_request_slot *slot = active_queue_head;
 783
 784        while (slot != NULL)
 785                if (slot->in_use) {
 786                        run_active_slot(slot);
 787                        slot = active_queue_head;
 788                } else {
 789                        slot = slot->next;
 790                }
 791}
 792
 793/* Helpers for modifying and creating URLs */
 794static inline int needs_quote(int ch)
 795{
 796        if (((ch >= 'A') && (ch <= 'Z'))
 797                        || ((ch >= 'a') && (ch <= 'z'))
 798                        || ((ch >= '0') && (ch <= '9'))
 799                        || (ch == '/')
 800                        || (ch == '-')
 801                        || (ch == '.'))
 802                return 0;
 803        return 1;
 804}
 805
 806static char *quote_ref_url(const char *base, const char *ref)
 807{
 808        struct strbuf buf = STRBUF_INIT;
 809        const char *cp;
 810        int ch;
 811
 812        end_url_with_slash(&buf, base);
 813
 814        for (cp = ref; (ch = *cp) != 0; cp++)
 815                if (needs_quote(ch))
 816                        strbuf_addf(&buf, "%%%02x", ch);
 817                else
 818                        strbuf_addch(&buf, *cp);
 819
 820        return strbuf_detach(&buf, NULL);
 821}
 822
 823void append_remote_object_url(struct strbuf *buf, const char *url,
 824                              const char *hex,
 825                              int only_two_digit_prefix)
 826{
 827        end_url_with_slash(buf, url);
 828
 829        strbuf_addf(buf, "objects/%.*s/", 2, hex);
 830        if (!only_two_digit_prefix)
 831                strbuf_addf(buf, "%s", hex+2);
 832}
 833
 834char *get_remote_object_url(const char *url, const char *hex,
 835                            int only_two_digit_prefix)
 836{
 837        struct strbuf buf = STRBUF_INIT;
 838        append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
 839        return strbuf_detach(&buf, NULL);
 840}
 841
 842int handle_curl_result(struct slot_results *results)
 843{
 844        /*
 845         * If we see a failing http code with CURLE_OK, we have turned off
 846         * FAILONERROR (to keep the server's custom error response), and should
 847         * translate the code into failure here.
 848         */
 849        if (results->curl_result == CURLE_OK &&
 850            results->http_code >= 400) {
 851                results->curl_result = CURLE_HTTP_RETURNED_ERROR;
 852                /*
 853                 * Normally curl will already have put the "reason phrase"
 854                 * from the server into curl_errorstr; unfortunately without
 855                 * FAILONERROR it is lost, so we can give only the numeric
 856                 * status code.
 857                 */
 858                snprintf(curl_errorstr, sizeof(curl_errorstr),
 859                         "The requested URL returned error: %ld",
 860                         results->http_code);
 861        }
 862
 863        if (results->curl_result == CURLE_OK) {
 864                credential_approve(&http_auth);
 865                return HTTP_OK;
 866        } else if (missing_target(results))
 867                return HTTP_MISSING_TARGET;
 868        else if (results->http_code == 401) {
 869                if (http_auth.username && http_auth.password) {
 870                        credential_reject(&http_auth);
 871                        return HTTP_NOAUTH;
 872                } else {
 873                        return HTTP_REAUTH;
 874                }
 875        } else {
 876#if LIBCURL_VERSION_NUM >= 0x070c00
 877                if (!curl_errorstr[0])
 878                        strlcpy(curl_errorstr,
 879                                curl_easy_strerror(results->curl_result),
 880                                sizeof(curl_errorstr));
 881#endif
 882                return HTTP_ERROR;
 883        }
 884}
 885
 886int run_one_slot(struct active_request_slot *slot,
 887                 struct slot_results *results)
 888{
 889        slot->results = results;
 890        if (!start_active_slot(slot)) {
 891                snprintf(curl_errorstr, sizeof(curl_errorstr),
 892                         "failed to start HTTP request");
 893                return HTTP_START_FAILED;
 894        }
 895
 896        run_active_slot(slot);
 897        return handle_curl_result(results);
 898}
 899
 900static CURLcode curlinfo_strbuf(CURL *curl, CURLINFO info, struct strbuf *buf)
 901{
 902        char *ptr;
 903        CURLcode ret;
 904
 905        strbuf_reset(buf);
 906        ret = curl_easy_getinfo(curl, info, &ptr);
 907        if (!ret && ptr)
 908                strbuf_addstr(buf, ptr);
 909        return ret;
 910}
 911
 912/*
 913 * Check for and extract a content-type parameter. "raw"
 914 * should be positioned at the start of the potential
 915 * parameter, with any whitespace already removed.
 916 *
 917 * "name" is the name of the parameter. The value is appended
 918 * to "out".
 919 */
 920static int extract_param(const char *raw, const char *name,
 921                         struct strbuf *out)
 922{
 923        size_t len = strlen(name);
 924
 925        if (strncasecmp(raw, name, len))
 926                return -1;
 927        raw += len;
 928
 929        if (*raw != '=')
 930                return -1;
 931        raw++;
 932
 933        while (*raw && !isspace(*raw) && *raw != ';')
 934                strbuf_addch(out, *raw++);
 935        return 0;
 936}
 937
 938/*
 939 * Extract a normalized version of the content type, with any
 940 * spaces suppressed, all letters lowercased, and no trailing ";"
 941 * or parameters.
 942 *
 943 * Note that we will silently remove even invalid whitespace. For
 944 * example, "text / plain" is specifically forbidden by RFC 2616,
 945 * but "text/plain" is the only reasonable output, and this keeps
 946 * our code simple.
 947 *
 948 * If the "charset" argument is not NULL, store the value of any
 949 * charset parameter there.
 950 *
 951 * Example:
 952 *   "TEXT/PLAIN; charset=utf-8" -> "text/plain", "utf-8"
 953 *   "text / plain" -> "text/plain"
 954 */
 955static void extract_content_type(struct strbuf *raw, struct strbuf *type,
 956                                 struct strbuf *charset)
 957{
 958        const char *p;
 959
 960        strbuf_reset(type);
 961        strbuf_grow(type, raw->len);
 962        for (p = raw->buf; *p; p++) {
 963                if (isspace(*p))
 964                        continue;
 965                if (*p == ';') {
 966                        p++;
 967                        break;
 968                }
 969                strbuf_addch(type, tolower(*p));
 970        }
 971
 972        if (!charset)
 973                return;
 974
 975        strbuf_reset(charset);
 976        while (*p) {
 977                while (isspace(*p) || *p == ';')
 978                        p++;
 979                if (!extract_param(p, "charset", charset))
 980                        return;
 981                while (*p && !isspace(*p))
 982                        p++;
 983        }
 984
 985        if (!charset->len && starts_with(type->buf, "text/"))
 986                strbuf_addstr(charset, "ISO-8859-1");
 987}
 988
 989/* http_request() targets */
 990#define HTTP_REQUEST_STRBUF     0
 991#define HTTP_REQUEST_FILE       1
 992
 993static int http_request(const char *url,
 994                        void *result, int target,
 995                        const struct http_get_options *options)
 996{
 997        struct active_request_slot *slot;
 998        struct slot_results results;
 999        struct curl_slist *headers = NULL;
1000        struct strbuf buf = STRBUF_INIT;
1001        int ret;
1002
1003        slot = get_active_slot();
1004        curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1005
1006        if (result == NULL) {
1007                curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
1008        } else {
1009                curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
1010                curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
1011
1012                if (target == HTTP_REQUEST_FILE) {
1013                        long posn = ftell(result);
1014                        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1015                                         fwrite);
1016                        if (posn > 0) {
1017                                strbuf_addf(&buf, "Range: bytes=%ld-", posn);
1018                                headers = curl_slist_append(headers, buf.buf);
1019                                strbuf_reset(&buf);
1020                        }
1021                } else
1022                        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1023                                         fwrite_buffer);
1024        }
1025
1026        strbuf_addstr(&buf, "Pragma:");
1027        if (options && options->no_cache)
1028                strbuf_addstr(&buf, " no-cache");
1029        if (options && options->keep_error)
1030                curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
1031
1032        headers = curl_slist_append(headers, buf.buf);
1033
1034        curl_easy_setopt(slot->curl, CURLOPT_URL, url);
1035        curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
1036        curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "gzip");
1037
1038        ret = run_one_slot(slot, &results);
1039
1040        if (options && options->content_type) {
1041                struct strbuf raw = STRBUF_INIT;
1042                curlinfo_strbuf(slot->curl, CURLINFO_CONTENT_TYPE, &raw);
1043                extract_content_type(&raw, options->content_type,
1044                                     options->charset);
1045                strbuf_release(&raw);
1046        }
1047
1048        if (options && options->effective_url)
1049                curlinfo_strbuf(slot->curl, CURLINFO_EFFECTIVE_URL,
1050                                options->effective_url);
1051
1052        curl_slist_free_all(headers);
1053        strbuf_release(&buf);
1054
1055        return ret;
1056}
1057
1058/*
1059 * Update the "base" url to a more appropriate value, as deduced by
1060 * redirects seen when requesting a URL starting with "url".
1061 *
1062 * The "asked" parameter is a URL that we asked curl to access, and must begin
1063 * with "base".
1064 *
1065 * The "got" parameter is the URL that curl reported to us as where we ended
1066 * up.
1067 *
1068 * Returns 1 if we updated the base url, 0 otherwise.
1069 *
1070 * Our basic strategy is to compare "base" and "asked" to find the bits
1071 * specific to our request. We then strip those bits off of "got" to yield the
1072 * new base. So for example, if our base is "http://example.com/foo.git",
1073 * and we ask for "http://example.com/foo.git/info/refs", we might end up
1074 * with "https://other.example.com/foo.git/info/refs". We would want the
1075 * new URL to become "https://other.example.com/foo.git".
1076 *
1077 * Note that this assumes a sane redirect scheme. It's entirely possible
1078 * in the example above to end up at a URL that does not even end in
1079 * "info/refs".  In such a case we simply punt, as there is not much we can
1080 * do (and such a scheme is unlikely to represent a real git repository,
1081 * which means we are likely about to abort anyway).
1082 */
1083static int update_url_from_redirect(struct strbuf *base,
1084                                    const char *asked,
1085                                    const struct strbuf *got)
1086{
1087        const char *tail;
1088        size_t tail_len;
1089
1090        if (!strcmp(asked, got->buf))
1091                return 0;
1092
1093        if (!skip_prefix(asked, base->buf, &tail))
1094                die("BUG: update_url_from_redirect: %s is not a superset of %s",
1095                    asked, base->buf);
1096
1097        tail_len = strlen(tail);
1098
1099        if (got->len < tail_len ||
1100            strcmp(tail, got->buf + got->len - tail_len))
1101                return 0; /* insane redirect scheme */
1102
1103        strbuf_reset(base);
1104        strbuf_add(base, got->buf, got->len - tail_len);
1105        return 1;
1106}
1107
1108static int http_request_reauth(const char *url,
1109                               void *result, int target,
1110                               struct http_get_options *options)
1111{
1112        int ret = http_request(url, result, target, options);
1113
1114        if (options && options->effective_url && options->base_url) {
1115                if (update_url_from_redirect(options->base_url,
1116                                             url, options->effective_url)) {
1117                        credential_from_url(&http_auth, options->base_url->buf);
1118                        url = options->effective_url->buf;
1119                }
1120        }
1121
1122        if (ret != HTTP_REAUTH)
1123                return ret;
1124
1125        /*
1126         * If we are using KEEP_ERROR, the previous request may have
1127         * put cruft into our output stream; we should clear it out before
1128         * making our next request. We only know how to do this for
1129         * the strbuf case, but that is enough to satisfy current callers.
1130         */
1131        if (options && options->keep_error) {
1132                switch (target) {
1133                case HTTP_REQUEST_STRBUF:
1134                        strbuf_reset(result);
1135                        break;
1136                default:
1137                        die("BUG: HTTP_KEEP_ERROR is only supported with strbufs");
1138                }
1139        }
1140
1141        credential_fill(&http_auth);
1142
1143        return http_request(url, result, target, options);
1144}
1145
1146int http_get_strbuf(const char *url,
1147                    struct strbuf *result,
1148                    struct http_get_options *options)
1149{
1150        return http_request_reauth(url, result, HTTP_REQUEST_STRBUF, options);
1151}
1152
1153/*
1154 * Downloads a URL and stores the result in the given file.
1155 *
1156 * If a previous interrupted download is detected (i.e. a previous temporary
1157 * file is still around) the download is resumed.
1158 */
1159static int http_get_file(const char *url, const char *filename,
1160                         struct http_get_options *options)
1161{
1162        int ret;
1163        struct strbuf tmpfile = STRBUF_INIT;
1164        FILE *result;
1165
1166        strbuf_addf(&tmpfile, "%s.temp", filename);
1167        result = fopen(tmpfile.buf, "a");
1168        if (!result) {
1169                error("Unable to open local file %s", tmpfile.buf);
1170                ret = HTTP_ERROR;
1171                goto cleanup;
1172        }
1173
1174        ret = http_request_reauth(url, result, HTTP_REQUEST_FILE, options);
1175        fclose(result);
1176
1177        if (ret == HTTP_OK && move_temp_to_file(tmpfile.buf, filename))
1178                ret = HTTP_ERROR;
1179cleanup:
1180        strbuf_release(&tmpfile);
1181        return ret;
1182}
1183
1184int http_fetch_ref(const char *base, struct ref *ref)
1185{
1186        struct http_get_options options = {0};
1187        char *url;
1188        struct strbuf buffer = STRBUF_INIT;
1189        int ret = -1;
1190
1191        options.no_cache = 1;
1192
1193        url = quote_ref_url(base, ref->name);
1194        if (http_get_strbuf(url, &buffer, &options) == HTTP_OK) {
1195                strbuf_rtrim(&buffer);
1196                if (buffer.len == 40)
1197                        ret = get_sha1_hex(buffer.buf, ref->old_sha1);
1198                else if (starts_with(buffer.buf, "ref: ")) {
1199                        ref->symref = xstrdup(buffer.buf + 5);
1200                        ret = 0;
1201                }
1202        }
1203
1204        strbuf_release(&buffer);
1205        free(url);
1206        return ret;
1207}
1208
1209/* Helpers for fetching packs */
1210static char *fetch_pack_index(unsigned char *sha1, const char *base_url)
1211{
1212        char *url, *tmp;
1213        struct strbuf buf = STRBUF_INIT;
1214
1215        if (http_is_verbose)
1216                fprintf(stderr, "Getting index for pack %s\n", sha1_to_hex(sha1));
1217
1218        end_url_with_slash(&buf, base_url);
1219        strbuf_addf(&buf, "objects/pack/pack-%s.idx", sha1_to_hex(sha1));
1220        url = strbuf_detach(&buf, NULL);
1221
1222        strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(sha1));
1223        tmp = strbuf_detach(&buf, NULL);
1224
1225        if (http_get_file(url, tmp, NULL) != HTTP_OK) {
1226                error("Unable to get pack index %s", url);
1227                free(tmp);
1228                tmp = NULL;
1229        }
1230
1231        free(url);
1232        return tmp;
1233}
1234
1235static int fetch_and_setup_pack_index(struct packed_git **packs_head,
1236        unsigned char *sha1, const char *base_url)
1237{
1238        struct packed_git *new_pack;
1239        char *tmp_idx = NULL;
1240        int ret;
1241
1242        if (has_pack_index(sha1)) {
1243                new_pack = parse_pack_index(sha1, NULL);
1244                if (!new_pack)
1245                        return -1; /* parse_pack_index() already issued error message */
1246                goto add_pack;
1247        }
1248
1249        tmp_idx = fetch_pack_index(sha1, base_url);
1250        if (!tmp_idx)
1251                return -1;
1252
1253        new_pack = parse_pack_index(sha1, tmp_idx);
1254        if (!new_pack) {
1255                unlink(tmp_idx);
1256                free(tmp_idx);
1257
1258                return -1; /* parse_pack_index() already issued error message */
1259        }
1260
1261        ret = verify_pack_index(new_pack);
1262        if (!ret) {
1263                close_pack_index(new_pack);
1264                ret = move_temp_to_file(tmp_idx, sha1_pack_index_name(sha1));
1265        }
1266        free(tmp_idx);
1267        if (ret)
1268                return -1;
1269
1270add_pack:
1271        new_pack->next = *packs_head;
1272        *packs_head = new_pack;
1273        return 0;
1274}
1275
1276int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
1277{
1278        struct http_get_options options = {0};
1279        int ret = 0, i = 0;
1280        char *url, *data;
1281        struct strbuf buf = STRBUF_INIT;
1282        unsigned char sha1[20];
1283
1284        end_url_with_slash(&buf, base_url);
1285        strbuf_addstr(&buf, "objects/info/packs");
1286        url = strbuf_detach(&buf, NULL);
1287
1288        options.no_cache = 1;
1289        ret = http_get_strbuf(url, &buf, &options);
1290        if (ret != HTTP_OK)
1291                goto cleanup;
1292
1293        data = buf.buf;
1294        while (i < buf.len) {
1295                switch (data[i]) {
1296                case 'P':
1297                        i++;
1298                        if (i + 52 <= buf.len &&
1299                            starts_with(data + i, " pack-") &&
1300                            starts_with(data + i + 46, ".pack\n")) {
1301                                get_sha1_hex(data + i + 6, sha1);
1302                                fetch_and_setup_pack_index(packs_head, sha1,
1303                                                      base_url);
1304                                i += 51;
1305                                break;
1306                        }
1307                default:
1308                        while (i < buf.len && data[i] != '\n')
1309                                i++;
1310                }
1311                i++;
1312        }
1313
1314cleanup:
1315        free(url);
1316        return ret;
1317}
1318
1319void release_http_pack_request(struct http_pack_request *preq)
1320{
1321        if (preq->packfile != NULL) {
1322                fclose(preq->packfile);
1323                preq->packfile = NULL;
1324        }
1325        if (preq->range_header != NULL) {
1326                curl_slist_free_all(preq->range_header);
1327                preq->range_header = NULL;
1328        }
1329        preq->slot = NULL;
1330        free(preq->url);
1331}
1332
1333int finish_http_pack_request(struct http_pack_request *preq)
1334{
1335        struct packed_git **lst;
1336        struct packed_git *p = preq->target;
1337        char *tmp_idx;
1338        struct child_process ip = CHILD_PROCESS_INIT;
1339        const char *ip_argv[8];
1340
1341        close_pack_index(p);
1342
1343        fclose(preq->packfile);
1344        preq->packfile = NULL;
1345
1346        lst = preq->lst;
1347        while (*lst != p)
1348                lst = &((*lst)->next);
1349        *lst = (*lst)->next;
1350
1351        tmp_idx = xstrdup(preq->tmpfile);
1352        strcpy(tmp_idx + strlen(tmp_idx) - strlen(".pack.temp"),
1353               ".idx.temp");
1354
1355        ip_argv[0] = "index-pack";
1356        ip_argv[1] = "-o";
1357        ip_argv[2] = tmp_idx;
1358        ip_argv[3] = preq->tmpfile;
1359        ip_argv[4] = NULL;
1360
1361        ip.argv = ip_argv;
1362        ip.git_cmd = 1;
1363        ip.no_stdin = 1;
1364        ip.no_stdout = 1;
1365
1366        if (run_command(&ip)) {
1367                unlink(preq->tmpfile);
1368                unlink(tmp_idx);
1369                free(tmp_idx);
1370                return -1;
1371        }
1372
1373        unlink(sha1_pack_index_name(p->sha1));
1374
1375        if (move_temp_to_file(preq->tmpfile, sha1_pack_name(p->sha1))
1376         || move_temp_to_file(tmp_idx, sha1_pack_index_name(p->sha1))) {
1377                free(tmp_idx);
1378                return -1;
1379        }
1380
1381        install_packed_git(p);
1382        free(tmp_idx);
1383        return 0;
1384}
1385
1386struct http_pack_request *new_http_pack_request(
1387        struct packed_git *target, const char *base_url)
1388{
1389        long prev_posn = 0;
1390        char range[RANGE_HEADER_SIZE];
1391        struct strbuf buf = STRBUF_INIT;
1392        struct http_pack_request *preq;
1393
1394        preq = xcalloc(1, sizeof(*preq));
1395        preq->target = target;
1396
1397        end_url_with_slash(&buf, base_url);
1398        strbuf_addf(&buf, "objects/pack/pack-%s.pack",
1399                sha1_to_hex(target->sha1));
1400        preq->url = strbuf_detach(&buf, NULL);
1401
1402        snprintf(preq->tmpfile, sizeof(preq->tmpfile), "%s.temp",
1403                sha1_pack_name(target->sha1));
1404        preq->packfile = fopen(preq->tmpfile, "a");
1405        if (!preq->packfile) {
1406                error("Unable to open local file %s for pack",
1407                      preq->tmpfile);
1408                goto abort;
1409        }
1410
1411        preq->slot = get_active_slot();
1412        curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
1413        curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
1414        curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
1415        curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1416                no_pragma_header);
1417
1418        /*
1419         * If there is data present from a previous transfer attempt,
1420         * resume where it left off
1421         */
1422        prev_posn = ftell(preq->packfile);
1423        if (prev_posn>0) {
1424                if (http_is_verbose)
1425                        fprintf(stderr,
1426                                "Resuming fetch of pack %s at byte %ld\n",
1427                                sha1_to_hex(target->sha1), prev_posn);
1428                sprintf(range, "Range: bytes=%ld-", prev_posn);
1429                preq->range_header = curl_slist_append(NULL, range);
1430                curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1431                        preq->range_header);
1432        }
1433
1434        return preq;
1435
1436abort:
1437        free(preq->url);
1438        free(preq);
1439        return NULL;
1440}
1441
1442/* Helpers for fetching objects (loose) */
1443static size_t fwrite_sha1_file(char *ptr, size_t eltsize, size_t nmemb,
1444                               void *data)
1445{
1446        unsigned char expn[4096];
1447        size_t size = eltsize * nmemb;
1448        int posn = 0;
1449        struct http_object_request *freq =
1450                (struct http_object_request *)data;
1451        do {
1452                ssize_t retval = xwrite(freq->localfile,
1453                                        (char *) ptr + posn, size - posn);
1454                if (retval < 0)
1455                        return posn;
1456                posn += retval;
1457        } while (posn < size);
1458
1459        freq->stream.avail_in = size;
1460        freq->stream.next_in = (void *)ptr;
1461        do {
1462                freq->stream.next_out = expn;
1463                freq->stream.avail_out = sizeof(expn);
1464                freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
1465                git_SHA1_Update(&freq->c, expn,
1466                                sizeof(expn) - freq->stream.avail_out);
1467        } while (freq->stream.avail_in && freq->zret == Z_OK);
1468        return size;
1469}
1470
1471struct http_object_request *new_http_object_request(const char *base_url,
1472        unsigned char *sha1)
1473{
1474        char *hex = sha1_to_hex(sha1);
1475        const char *filename;
1476        char prevfile[PATH_MAX];
1477        int prevlocal;
1478        char prev_buf[PREV_BUF_SIZE];
1479        ssize_t prev_read = 0;
1480        long prev_posn = 0;
1481        char range[RANGE_HEADER_SIZE];
1482        struct curl_slist *range_header = NULL;
1483        struct http_object_request *freq;
1484
1485        freq = xcalloc(1, sizeof(*freq));
1486        hashcpy(freq->sha1, sha1);
1487        freq->localfile = -1;
1488
1489        filename = sha1_file_name(sha1);
1490        snprintf(freq->tmpfile, sizeof(freq->tmpfile),
1491                 "%s.temp", filename);
1492
1493        snprintf(prevfile, sizeof(prevfile), "%s.prev", filename);
1494        unlink_or_warn(prevfile);
1495        rename(freq->tmpfile, prevfile);
1496        unlink_or_warn(freq->tmpfile);
1497
1498        if (freq->localfile != -1)
1499                error("fd leakage in start: %d", freq->localfile);
1500        freq->localfile = open(freq->tmpfile,
1501                               O_WRONLY | O_CREAT | O_EXCL, 0666);
1502        /*
1503         * This could have failed due to the "lazy directory creation";
1504         * try to mkdir the last path component.
1505         */
1506        if (freq->localfile < 0 && errno == ENOENT) {
1507                char *dir = strrchr(freq->tmpfile, '/');
1508                if (dir) {
1509                        *dir = 0;
1510                        mkdir(freq->tmpfile, 0777);
1511                        *dir = '/';
1512                }
1513                freq->localfile = open(freq->tmpfile,
1514                                       O_WRONLY | O_CREAT | O_EXCL, 0666);
1515        }
1516
1517        if (freq->localfile < 0) {
1518                error("Couldn't create temporary file %s: %s",
1519                      freq->tmpfile, strerror(errno));
1520                goto abort;
1521        }
1522
1523        git_inflate_init(&freq->stream);
1524
1525        git_SHA1_Init(&freq->c);
1526
1527        freq->url = get_remote_object_url(base_url, hex, 0);
1528
1529        /*
1530         * If a previous temp file is present, process what was already
1531         * fetched.
1532         */
1533        prevlocal = open(prevfile, O_RDONLY);
1534        if (prevlocal != -1) {
1535                do {
1536                        prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
1537                        if (prev_read>0) {
1538                                if (fwrite_sha1_file(prev_buf,
1539                                                     1,
1540                                                     prev_read,
1541                                                     freq) == prev_read) {
1542                                        prev_posn += prev_read;
1543                                } else {
1544                                        prev_read = -1;
1545                                }
1546                        }
1547                } while (prev_read > 0);
1548                close(prevlocal);
1549        }
1550        unlink_or_warn(prevfile);
1551
1552        /*
1553         * Reset inflate/SHA1 if there was an error reading the previous temp
1554         * file; also rewind to the beginning of the local file.
1555         */
1556        if (prev_read == -1) {
1557                memset(&freq->stream, 0, sizeof(freq->stream));
1558                git_inflate_init(&freq->stream);
1559                git_SHA1_Init(&freq->c);
1560                if (prev_posn>0) {
1561                        prev_posn = 0;
1562                        lseek(freq->localfile, 0, SEEK_SET);
1563                        if (ftruncate(freq->localfile, 0) < 0) {
1564                                error("Couldn't truncate temporary file %s: %s",
1565                                          freq->tmpfile, strerror(errno));
1566                                goto abort;
1567                        }
1568                }
1569        }
1570
1571        freq->slot = get_active_slot();
1572
1573        curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
1574        curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
1575        curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
1576        curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
1577        curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
1578
1579        /*
1580         * If we have successfully processed data from a previous fetch
1581         * attempt, only fetch the data we don't already have.
1582         */
1583        if (prev_posn>0) {
1584                if (http_is_verbose)
1585                        fprintf(stderr,
1586                                "Resuming fetch of object %s at byte %ld\n",
1587                                hex, prev_posn);
1588                sprintf(range, "Range: bytes=%ld-", prev_posn);
1589                range_header = curl_slist_append(range_header, range);
1590                curl_easy_setopt(freq->slot->curl,
1591                                 CURLOPT_HTTPHEADER, range_header);
1592        }
1593
1594        return freq;
1595
1596abort:
1597        free(freq->url);
1598        free(freq);
1599        return NULL;
1600}
1601
1602void process_http_object_request(struct http_object_request *freq)
1603{
1604        if (freq->slot == NULL)
1605                return;
1606        freq->curl_result = freq->slot->curl_result;
1607        freq->http_code = freq->slot->http_code;
1608        freq->slot = NULL;
1609}
1610
1611int finish_http_object_request(struct http_object_request *freq)
1612{
1613        struct stat st;
1614
1615        close(freq->localfile);
1616        freq->localfile = -1;
1617
1618        process_http_object_request(freq);
1619
1620        if (freq->http_code == 416) {
1621                warning("requested range invalid; we may already have all the data.");
1622        } else if (freq->curl_result != CURLE_OK) {
1623                if (stat(freq->tmpfile, &st) == 0)
1624                        if (st.st_size == 0)
1625                                unlink_or_warn(freq->tmpfile);
1626                return -1;
1627        }
1628
1629        git_inflate_end(&freq->stream);
1630        git_SHA1_Final(freq->real_sha1, &freq->c);
1631        if (freq->zret != Z_STREAM_END) {
1632                unlink_or_warn(freq->tmpfile);
1633                return -1;
1634        }
1635        if (hashcmp(freq->sha1, freq->real_sha1)) {
1636                unlink_or_warn(freq->tmpfile);
1637                return -1;
1638        }
1639        freq->rename =
1640                move_temp_to_file(freq->tmpfile, sha1_file_name(freq->sha1));
1641
1642        return freq->rename;
1643}
1644
1645void abort_http_object_request(struct http_object_request *freq)
1646{
1647        unlink_or_warn(freq->tmpfile);
1648
1649        release_http_object_request(freq);
1650}
1651
1652void release_http_object_request(struct http_object_request *freq)
1653{
1654        if (freq->localfile != -1) {
1655                close(freq->localfile);
1656                freq->localfile = -1;
1657        }
1658        if (freq->url != NULL) {
1659                free(freq->url);
1660                freq->url = NULL;
1661        }
1662        if (freq->slot != NULL) {
1663                freq->slot->callback_func = NULL;
1664                freq->slot->callback_data = NULL;
1665                release_active_slot(freq->slot);
1666                freq->slot = NULL;
1667        }
1668}