Andrew's git / gitweb.git / http.c
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http.con commit fsck: treat a NUL in a tag header as an error (8a272f2)
   1#include "git-compat-util.h"
   2#include "http.h"
   3#include "pack.h"
   4#include "sideband.h"
   5#include "run-command.h"
   6#include "url.h"
   7#include "urlmatch.h"
   8#include "credential.h"
   9#include "version.h"
  10#include "pkt-line.h"
  11#include "gettext.h"
  12#include "transport.h"
  13
  14int active_requests;
  15int http_is_verbose;
  16size_t http_post_buffer = 16 * LARGE_PACKET_MAX;
  17
  18#if LIBCURL_VERSION_NUM >= 0x070a06
  19#define LIBCURL_CAN_HANDLE_AUTH_ANY
  20#endif
  21
  22static int min_curl_sessions = 1;
  23static int curl_session_count;
  24#ifdef USE_CURL_MULTI
  25static int max_requests = -1;
  26static CURLM *curlm;
  27#endif
  28#ifndef NO_CURL_EASY_DUPHANDLE
  29static CURL *curl_default;
  30#endif
  31
  32#define PREV_BUF_SIZE 4096
  33
  34char curl_errorstr[CURL_ERROR_SIZE];
  35
  36static int curl_ssl_verify = -1;
  37static int curl_ssl_try;
  38static const char *ssl_cert;
  39static const char *ssl_cipherlist;
  40static const char *ssl_version;
  41static struct {
  42        const char *name;
  43        long ssl_version;
  44} sslversions[] = {
  45        { "sslv2", CURL_SSLVERSION_SSLv2 },
  46        { "sslv3", CURL_SSLVERSION_SSLv3 },
  47        { "tlsv1", CURL_SSLVERSION_TLSv1 },
  48#if LIBCURL_VERSION_NUM >= 0x072200
  49        { "tlsv1.0", CURL_SSLVERSION_TLSv1_0 },
  50        { "tlsv1.1", CURL_SSLVERSION_TLSv1_1 },
  51        { "tlsv1.2", CURL_SSLVERSION_TLSv1_2 },
  52#endif
  53};
  54#if LIBCURL_VERSION_NUM >= 0x070903
  55static const char *ssl_key;
  56#endif
  57#if LIBCURL_VERSION_NUM >= 0x070908
  58static const char *ssl_capath;
  59#endif
  60static const char *ssl_cainfo;
  61static long curl_low_speed_limit = -1;
  62static long curl_low_speed_time = -1;
  63static int curl_ftp_no_epsv;
  64static const char *curl_http_proxy;
  65static const char *curl_cookie_file;
  66static int curl_save_cookies;
  67struct credential http_auth = CREDENTIAL_INIT;
  68static int http_proactive_auth;
  69static const char *user_agent;
  70
  71#if LIBCURL_VERSION_NUM >= 0x071700
  72/* Use CURLOPT_KEYPASSWD as is */
  73#elif LIBCURL_VERSION_NUM >= 0x070903
  74#define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
  75#else
  76#define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
  77#endif
  78
  79static struct credential cert_auth = CREDENTIAL_INIT;
  80static int ssl_cert_password_required;
  81#ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
  82static unsigned long http_auth_methods = CURLAUTH_ANY;
  83#endif
  84
  85static struct curl_slist *pragma_header;
  86static struct curl_slist *no_pragma_header;
  87
  88static struct active_request_slot *active_queue_head;
  89
  90static char *cached_accept_language;
  91
  92size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
  93{
  94        size_t size = eltsize * nmemb;
  95        struct buffer *buffer = buffer_;
  96
  97        if (size > buffer->buf.len - buffer->posn)
  98                size = buffer->buf.len - buffer->posn;
  99        memcpy(ptr, buffer->buf.buf + buffer->posn, size);
 100        buffer->posn += size;
 101
 102        return size;
 103}
 104
 105#ifndef NO_CURL_IOCTL
 106curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
 107{
 108        struct buffer *buffer = clientp;
 109
 110        switch (cmd) {
 111        case CURLIOCMD_NOP:
 112                return CURLIOE_OK;
 113
 114        case CURLIOCMD_RESTARTREAD:
 115                buffer->posn = 0;
 116                return CURLIOE_OK;
 117
 118        default:
 119                return CURLIOE_UNKNOWNCMD;
 120        }
 121}
 122#endif
 123
 124size_t fwrite_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
 125{
 126        size_t size = eltsize * nmemb;
 127        struct strbuf *buffer = buffer_;
 128
 129        strbuf_add(buffer, ptr, size);
 130        return size;
 131}
 132
 133size_t fwrite_null(char *ptr, size_t eltsize, size_t nmemb, void *strbuf)
 134{
 135        return eltsize * nmemb;
 136}
 137
 138static void closedown_active_slot(struct active_request_slot *slot)
 139{
 140        active_requests--;
 141        slot->in_use = 0;
 142}
 143
 144static void finish_active_slot(struct active_request_slot *slot)
 145{
 146        closedown_active_slot(slot);
 147        curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
 148
 149        if (slot->finished != NULL)
 150                (*slot->finished) = 1;
 151
 152        /* Store slot results so they can be read after the slot is reused */
 153        if (slot->results != NULL) {
 154                slot->results->curl_result = slot->curl_result;
 155                slot->results->http_code = slot->http_code;
 156#if LIBCURL_VERSION_NUM >= 0x070a08
 157                curl_easy_getinfo(slot->curl, CURLINFO_HTTPAUTH_AVAIL,
 158                                  &slot->results->auth_avail);
 159#else
 160                slot->results->auth_avail = 0;
 161#endif
 162        }
 163
 164        /* Run callback if appropriate */
 165        if (slot->callback_func != NULL)
 166                slot->callback_func(slot->callback_data);
 167}
 168
 169#ifdef USE_CURL_MULTI
 170static void process_curl_messages(void)
 171{
 172        int num_messages;
 173        struct active_request_slot *slot;
 174        CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
 175
 176        while (curl_message != NULL) {
 177                if (curl_message->msg == CURLMSG_DONE) {
 178                        int curl_result = curl_message->data.result;
 179                        slot = active_queue_head;
 180                        while (slot != NULL &&
 181                               slot->curl != curl_message->easy_handle)
 182                                slot = slot->next;
 183                        if (slot != NULL) {
 184                                curl_multi_remove_handle(curlm, slot->curl);
 185                                slot->curl_result = curl_result;
 186                                finish_active_slot(slot);
 187                        } else {
 188                                fprintf(stderr, "Received DONE message for unknown request!\n");
 189                        }
 190                } else {
 191                        fprintf(stderr, "Unknown CURL message received: %d\n",
 192                                (int)curl_message->msg);
 193                }
 194                curl_message = curl_multi_info_read(curlm, &num_messages);
 195        }
 196}
 197#endif
 198
 199static int http_options(const char *var, const char *value, void *cb)
 200{
 201        if (!strcmp("http.sslverify", var)) {
 202                curl_ssl_verify = git_config_bool(var, value);
 203                return 0;
 204        }
 205        if (!strcmp("http.sslcipherlist", var))
 206                return git_config_string(&ssl_cipherlist, var, value);
 207        if (!strcmp("http.sslversion", var))
 208                return git_config_string(&ssl_version, var, value);
 209        if (!strcmp("http.sslcert", var))
 210                return git_config_string(&ssl_cert, var, value);
 211#if LIBCURL_VERSION_NUM >= 0x070903
 212        if (!strcmp("http.sslkey", var))
 213                return git_config_string(&ssl_key, var, value);
 214#endif
 215#if LIBCURL_VERSION_NUM >= 0x070908
 216        if (!strcmp("http.sslcapath", var))
 217                return git_config_string(&ssl_capath, var, value);
 218#endif
 219        if (!strcmp("http.sslcainfo", var))
 220                return git_config_string(&ssl_cainfo, var, value);
 221        if (!strcmp("http.sslcertpasswordprotected", var)) {
 222                ssl_cert_password_required = git_config_bool(var, value);
 223                return 0;
 224        }
 225        if (!strcmp("http.ssltry", var)) {
 226                curl_ssl_try = git_config_bool(var, value);
 227                return 0;
 228        }
 229        if (!strcmp("http.minsessions", var)) {
 230                min_curl_sessions = git_config_int(var, value);
 231#ifndef USE_CURL_MULTI
 232                if (min_curl_sessions > 1)
 233                        min_curl_sessions = 1;
 234#endif
 235                return 0;
 236        }
 237#ifdef USE_CURL_MULTI
 238        if (!strcmp("http.maxrequests", var)) {
 239                max_requests = git_config_int(var, value);
 240                return 0;
 241        }
 242#endif
 243        if (!strcmp("http.lowspeedlimit", var)) {
 244                curl_low_speed_limit = (long)git_config_int(var, value);
 245                return 0;
 246        }
 247        if (!strcmp("http.lowspeedtime", var)) {
 248                curl_low_speed_time = (long)git_config_int(var, value);
 249                return 0;
 250        }
 251
 252        if (!strcmp("http.noepsv", var)) {
 253                curl_ftp_no_epsv = git_config_bool(var, value);
 254                return 0;
 255        }
 256        if (!strcmp("http.proxy", var))
 257                return git_config_string(&curl_http_proxy, var, value);
 258
 259        if (!strcmp("http.cookiefile", var))
 260                return git_config_string(&curl_cookie_file, var, value);
 261        if (!strcmp("http.savecookies", var)) {
 262                curl_save_cookies = git_config_bool(var, value);
 263                return 0;
 264        }
 265
 266        if (!strcmp("http.postbuffer", var)) {
 267                http_post_buffer = git_config_int(var, value);
 268                if (http_post_buffer < LARGE_PACKET_MAX)
 269                        http_post_buffer = LARGE_PACKET_MAX;
 270                return 0;
 271        }
 272
 273        if (!strcmp("http.useragent", var))
 274                return git_config_string(&user_agent, var, value);
 275
 276        /* Fall back on the default ones */
 277        return git_default_config(var, value, cb);
 278}
 279
 280static void init_curl_http_auth(CURL *result)
 281{
 282        if (!http_auth.username)
 283                return;
 284
 285        credential_fill(&http_auth);
 286
 287#if LIBCURL_VERSION_NUM >= 0x071301
 288        curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username);
 289        curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password);
 290#else
 291        {
 292                static struct strbuf up = STRBUF_INIT;
 293                /*
 294                 * Note that we assume we only ever have a single set of
 295                 * credentials in a given program run, so we do not have
 296                 * to worry about updating this buffer, only setting its
 297                 * initial value.
 298                 */
 299                if (!up.len)
 300                        strbuf_addf(&up, "%s:%s",
 301                                http_auth.username, http_auth.password);
 302                curl_easy_setopt(result, CURLOPT_USERPWD, up.buf);
 303        }
 304#endif
 305}
 306
 307static int has_cert_password(void)
 308{
 309        if (ssl_cert == NULL || ssl_cert_password_required != 1)
 310                return 0;
 311        if (!cert_auth.password) {
 312                cert_auth.protocol = xstrdup("cert");
 313                cert_auth.username = xstrdup("");
 314                cert_auth.path = xstrdup(ssl_cert);
 315                credential_fill(&cert_auth);
 316        }
 317        return 1;
 318}
 319
 320#if LIBCURL_VERSION_NUM >= 0x071900
 321static void set_curl_keepalive(CURL *c)
 322{
 323        curl_easy_setopt(c, CURLOPT_TCP_KEEPALIVE, 1);
 324}
 325
 326#elif LIBCURL_VERSION_NUM >= 0x071000
 327static int sockopt_callback(void *client, curl_socket_t fd, curlsocktype type)
 328{
 329        int ka = 1;
 330        int rc;
 331        socklen_t len = (socklen_t)sizeof(ka);
 332
 333        if (type != CURLSOCKTYPE_IPCXN)
 334                return 0;
 335
 336        rc = setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&ka, len);
 337        if (rc < 0)
 338                warning("unable to set SO_KEEPALIVE on socket %s",
 339                        strerror(errno));
 340
 341        return 0; /* CURL_SOCKOPT_OK only exists since curl 7.21.5 */
 342}
 343
 344static void set_curl_keepalive(CURL *c)
 345{
 346        curl_easy_setopt(c, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
 347}
 348
 349#else
 350static void set_curl_keepalive(CURL *c)
 351{
 352        /* not supported on older curl versions */
 353}
 354#endif
 355
 356static CURL *get_curl_handle(void)
 357{
 358        CURL *result = curl_easy_init();
 359        long allowed_protocols = 0;
 360
 361        if (!result)
 362                die("curl_easy_init failed");
 363
 364        if (!curl_ssl_verify) {
 365                curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
 366                curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
 367        } else {
 368                /* Verify authenticity of the peer's certificate */
 369                curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
 370                /* The name in the cert must match whom we tried to connect */
 371                curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
 372        }
 373
 374#if LIBCURL_VERSION_NUM >= 0x070907
 375        curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
 376#endif
 377#ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 378        curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 379#endif
 380
 381        if (http_proactive_auth)
 382                init_curl_http_auth(result);
 383
 384        if (getenv("GIT_SSL_VERSION"))
 385                ssl_version = getenv("GIT_SSL_VERSION");
 386        if (ssl_version && *ssl_version) {
 387                int i;
 388                for (i = 0; i < ARRAY_SIZE(sslversions); i++) {
 389                        if (!strcmp(ssl_version, sslversions[i].name)) {
 390                                curl_easy_setopt(result, CURLOPT_SSLVERSION,
 391                                                 sslversions[i].ssl_version);
 392                                break;
 393                        }
 394                }
 395                if (i == ARRAY_SIZE(sslversions))
 396                        warning("unsupported ssl version %s: using default",
 397                                ssl_version);
 398        }
 399
 400        if (getenv("GIT_SSL_CIPHER_LIST"))
 401                ssl_cipherlist = getenv("GIT_SSL_CIPHER_LIST");
 402        if (ssl_cipherlist != NULL && *ssl_cipherlist)
 403                curl_easy_setopt(result, CURLOPT_SSL_CIPHER_LIST,
 404                                ssl_cipherlist);
 405
 406        if (ssl_cert != NULL)
 407                curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
 408        if (has_cert_password())
 409                curl_easy_setopt(result, CURLOPT_KEYPASSWD, cert_auth.password);
 410#if LIBCURL_VERSION_NUM >= 0x070903
 411        if (ssl_key != NULL)
 412                curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
 413#endif
 414#if LIBCURL_VERSION_NUM >= 0x070908
 415        if (ssl_capath != NULL)
 416                curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
 417#endif
 418        if (ssl_cainfo != NULL)
 419                curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
 420
 421        if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
 422                curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
 423                                 curl_low_speed_limit);
 424                curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
 425                                 curl_low_speed_time);
 426        }
 427
 428        curl_easy_setopt(result, CURLOPT_FOLLOWLOCATION, 1);
 429        curl_easy_setopt(result, CURLOPT_MAXREDIRS, 20);
 430#if LIBCURL_VERSION_NUM >= 0x071301
 431        curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
 432#elif LIBCURL_VERSION_NUM >= 0x071101
 433        curl_easy_setopt(result, CURLOPT_POST301, 1);
 434#endif
 435#if LIBCURL_VERSION_NUM >= 0x071304
 436        if (is_transport_allowed("http"))
 437                allowed_protocols |= CURLPROTO_HTTP;
 438        if (is_transport_allowed("https"))
 439                allowed_protocols |= CURLPROTO_HTTPS;
 440        if (is_transport_allowed("ftp"))
 441                allowed_protocols |= CURLPROTO_FTP;
 442        if (is_transport_allowed("ftps"))
 443                allowed_protocols |= CURLPROTO_FTPS;
 444        curl_easy_setopt(result, CURLOPT_REDIR_PROTOCOLS, allowed_protocols);
 445#else
 446        if (transport_restrict_protocols())
 447                warning("protocol restrictions not applied to curl redirects because\n"
 448                        "your curl version is too old (>= 7.19.4)");
 449#endif
 450
 451        if (getenv("GIT_CURL_VERBOSE"))
 452                curl_easy_setopt(result, CURLOPT_VERBOSE, 1);
 453
 454        curl_easy_setopt(result, CURLOPT_USERAGENT,
 455                user_agent ? user_agent : git_user_agent());
 456
 457        if (curl_ftp_no_epsv)
 458                curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
 459
 460#ifdef CURLOPT_USE_SSL
 461        if (curl_ssl_try)
 462                curl_easy_setopt(result, CURLOPT_USE_SSL, CURLUSESSL_TRY);
 463#endif
 464
 465        if (curl_http_proxy) {
 466                curl_easy_setopt(result, CURLOPT_PROXY, curl_http_proxy);
 467        }
 468#if LIBCURL_VERSION_NUM >= 0x070a07
 469        curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 470#endif
 471
 472        set_curl_keepalive(result);
 473
 474        return result;
 475}
 476
 477static void set_from_env(const char **var, const char *envname)
 478{
 479        const char *val = getenv(envname);
 480        if (val)
 481                *var = val;
 482}
 483
 484void http_init(struct remote *remote, const char *url, int proactive_auth)
 485{
 486        char *low_speed_limit;
 487        char *low_speed_time;
 488        char *normalized_url;
 489        struct urlmatch_config config = { STRING_LIST_INIT_DUP };
 490
 491        config.section = "http";
 492        config.key = NULL;
 493        config.collect_fn = http_options;
 494        config.cascade_fn = git_default_config;
 495        config.cb = NULL;
 496
 497        http_is_verbose = 0;
 498        normalized_url = url_normalize(url, &config.url);
 499
 500        git_config(urlmatch_config_entry, &config);
 501        free(normalized_url);
 502
 503        if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK)
 504                die("curl_global_init failed");
 505
 506        http_proactive_auth = proactive_auth;
 507
 508        if (remote && remote->http_proxy)
 509                curl_http_proxy = xstrdup(remote->http_proxy);
 510
 511        pragma_header = curl_slist_append(pragma_header, "Pragma: no-cache");
 512        no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
 513
 514#ifdef USE_CURL_MULTI
 515        {
 516                char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
 517                if (http_max_requests != NULL)
 518                        max_requests = atoi(http_max_requests);
 519        }
 520
 521        curlm = curl_multi_init();
 522        if (!curlm)
 523                die("curl_multi_init failed");
 524#endif
 525
 526        if (getenv("GIT_SSL_NO_VERIFY"))
 527                curl_ssl_verify = 0;
 528
 529        set_from_env(&ssl_cert, "GIT_SSL_CERT");
 530#if LIBCURL_VERSION_NUM >= 0x070903
 531        set_from_env(&ssl_key, "GIT_SSL_KEY");
 532#endif
 533#if LIBCURL_VERSION_NUM >= 0x070908
 534        set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
 535#endif
 536        set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
 537
 538        set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
 539
 540        low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
 541        if (low_speed_limit != NULL)
 542                curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
 543        low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
 544        if (low_speed_time != NULL)
 545                curl_low_speed_time = strtol(low_speed_time, NULL, 10);
 546
 547        if (curl_ssl_verify == -1)
 548                curl_ssl_verify = 1;
 549
 550        curl_session_count = 0;
 551#ifdef USE_CURL_MULTI
 552        if (max_requests < 1)
 553                max_requests = DEFAULT_MAX_REQUESTS;
 554#endif
 555
 556        if (getenv("GIT_CURL_FTP_NO_EPSV"))
 557                curl_ftp_no_epsv = 1;
 558
 559        if (url) {
 560                credential_from_url(&http_auth, url);
 561                if (!ssl_cert_password_required &&
 562                    getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
 563                    starts_with(url, "https://"))
 564                        ssl_cert_password_required = 1;
 565        }
 566
 567#ifndef NO_CURL_EASY_DUPHANDLE
 568        curl_default = get_curl_handle();
 569#endif
 570}
 571
 572void http_cleanup(void)
 573{
 574        struct active_request_slot *slot = active_queue_head;
 575
 576        while (slot != NULL) {
 577                struct active_request_slot *next = slot->next;
 578                if (slot->curl != NULL) {
 579#ifdef USE_CURL_MULTI
 580                        curl_multi_remove_handle(curlm, slot->curl);
 581#endif
 582                        curl_easy_cleanup(slot->curl);
 583                }
 584                free(slot);
 585                slot = next;
 586        }
 587        active_queue_head = NULL;
 588
 589#ifndef NO_CURL_EASY_DUPHANDLE
 590        curl_easy_cleanup(curl_default);
 591#endif
 592
 593#ifdef USE_CURL_MULTI
 594        curl_multi_cleanup(curlm);
 595#endif
 596        curl_global_cleanup();
 597
 598        curl_slist_free_all(pragma_header);
 599        pragma_header = NULL;
 600
 601        curl_slist_free_all(no_pragma_header);
 602        no_pragma_header = NULL;
 603
 604        if (curl_http_proxy) {
 605                free((void *)curl_http_proxy);
 606                curl_http_proxy = NULL;
 607        }
 608
 609        if (cert_auth.password != NULL) {
 610                memset(cert_auth.password, 0, strlen(cert_auth.password));
 611                free(cert_auth.password);
 612                cert_auth.password = NULL;
 613        }
 614        ssl_cert_password_required = 0;
 615
 616        free(cached_accept_language);
 617        cached_accept_language = NULL;
 618}
 619
 620struct active_request_slot *get_active_slot(void)
 621{
 622        struct active_request_slot *slot = active_queue_head;
 623        struct active_request_slot *newslot;
 624
 625#ifdef USE_CURL_MULTI
 626        int num_transfers;
 627
 628        /* Wait for a slot to open up if the queue is full */
 629        while (active_requests >= max_requests) {
 630                curl_multi_perform(curlm, &num_transfers);
 631                if (num_transfers < active_requests)
 632                        process_curl_messages();
 633        }
 634#endif
 635
 636        while (slot != NULL && slot->in_use)
 637                slot = slot->next;
 638
 639        if (slot == NULL) {
 640                newslot = xmalloc(sizeof(*newslot));
 641                newslot->curl = NULL;
 642                newslot->in_use = 0;
 643                newslot->next = NULL;
 644
 645                slot = active_queue_head;
 646                if (slot == NULL) {
 647                        active_queue_head = newslot;
 648                } else {
 649                        while (slot->next != NULL)
 650                                slot = slot->next;
 651                        slot->next = newslot;
 652                }
 653                slot = newslot;
 654        }
 655
 656        if (slot->curl == NULL) {
 657#ifdef NO_CURL_EASY_DUPHANDLE
 658                slot->curl = get_curl_handle();
 659#else
 660                slot->curl = curl_easy_duphandle(curl_default);
 661#endif
 662                curl_session_count++;
 663        }
 664
 665        active_requests++;
 666        slot->in_use = 1;
 667        slot->results = NULL;
 668        slot->finished = NULL;
 669        slot->callback_data = NULL;
 670        slot->callback_func = NULL;
 671        curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
 672        if (curl_save_cookies)
 673                curl_easy_setopt(slot->curl, CURLOPT_COOKIEJAR, curl_cookie_file);
 674        curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
 675        curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
 676        curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
 677        curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
 678        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
 679        curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
 680        curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
 681        curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 682        curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 1);
 683        curl_easy_setopt(slot->curl, CURLOPT_RANGE, NULL);
 684#ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 685        curl_easy_setopt(slot->curl, CURLOPT_HTTPAUTH, http_auth_methods);
 686#endif
 687        if (http_auth.password)
 688                init_curl_http_auth(slot->curl);
 689
 690        return slot;
 691}
 692
 693int start_active_slot(struct active_request_slot *slot)
 694{
 695#ifdef USE_CURL_MULTI
 696        CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
 697        int num_transfers;
 698
 699        if (curlm_result != CURLM_OK &&
 700            curlm_result != CURLM_CALL_MULTI_PERFORM) {
 701                active_requests--;
 702                slot->in_use = 0;
 703                return 0;
 704        }
 705
 706        /*
 707         * We know there must be something to do, since we just added
 708         * something.
 709         */
 710        curl_multi_perform(curlm, &num_transfers);
 711#endif
 712        return 1;
 713}
 714
 715#ifdef USE_CURL_MULTI
 716struct fill_chain {
 717        void *data;
 718        int (*fill)(void *);
 719        struct fill_chain *next;
 720};
 721
 722static struct fill_chain *fill_cfg;
 723
 724void add_fill_function(void *data, int (*fill)(void *))
 725{
 726        struct fill_chain *new = xmalloc(sizeof(*new));
 727        struct fill_chain **linkp = &fill_cfg;
 728        new->data = data;
 729        new->fill = fill;
 730        new->next = NULL;
 731        while (*linkp)
 732                linkp = &(*linkp)->next;
 733        *linkp = new;
 734}
 735
 736void fill_active_slots(void)
 737{
 738        struct active_request_slot *slot = active_queue_head;
 739
 740        while (active_requests < max_requests) {
 741                struct fill_chain *fill;
 742                for (fill = fill_cfg; fill; fill = fill->next)
 743                        if (fill->fill(fill->data))
 744                                break;
 745
 746                if (!fill)
 747                        break;
 748        }
 749
 750        while (slot != NULL) {
 751                if (!slot->in_use && slot->curl != NULL
 752                        && curl_session_count > min_curl_sessions) {
 753                        curl_easy_cleanup(slot->curl);
 754                        slot->curl = NULL;
 755                        curl_session_count--;
 756                }
 757                slot = slot->next;
 758        }
 759}
 760
 761void step_active_slots(void)
 762{
 763        int num_transfers;
 764        CURLMcode curlm_result;
 765
 766        do {
 767                curlm_result = curl_multi_perform(curlm, &num_transfers);
 768        } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
 769        if (num_transfers < active_requests) {
 770                process_curl_messages();
 771                fill_active_slots();
 772        }
 773}
 774#endif
 775
 776void run_active_slot(struct active_request_slot *slot)
 777{
 778#ifdef USE_CURL_MULTI
 779        fd_set readfds;
 780        fd_set writefds;
 781        fd_set excfds;
 782        int max_fd;
 783        struct timeval select_timeout;
 784        int finished = 0;
 785
 786        slot->finished = &finished;
 787        while (!finished) {
 788                step_active_slots();
 789
 790                if (slot->in_use) {
 791#if LIBCURL_VERSION_NUM >= 0x070f04
 792                        long curl_timeout;
 793                        curl_multi_timeout(curlm, &curl_timeout);
 794                        if (curl_timeout == 0) {
 795                                continue;
 796                        } else if (curl_timeout == -1) {
 797                                select_timeout.tv_sec  = 0;
 798                                select_timeout.tv_usec = 50000;
 799                        } else {
 800                                select_timeout.tv_sec  =  curl_timeout / 1000;
 801                                select_timeout.tv_usec = (curl_timeout % 1000) * 1000;
 802                        }
 803#else
 804                        select_timeout.tv_sec  = 0;
 805                        select_timeout.tv_usec = 50000;
 806#endif
 807
 808                        max_fd = -1;
 809                        FD_ZERO(&readfds);
 810                        FD_ZERO(&writefds);
 811                        FD_ZERO(&excfds);
 812                        curl_multi_fdset(curlm, &readfds, &writefds, &excfds, &max_fd);
 813
 814                        /*
 815                         * It can happen that curl_multi_timeout returns a pathologically
 816                         * long timeout when curl_multi_fdset returns no file descriptors
 817                         * to read.  See commit message for more details.
 818                         */
 819                        if (max_fd < 0 &&
 820                            (select_timeout.tv_sec > 0 ||
 821                             select_timeout.tv_usec > 50000)) {
 822                                select_timeout.tv_sec  = 0;
 823                                select_timeout.tv_usec = 50000;
 824                        }
 825
 826                        select(max_fd+1, &readfds, &writefds, &excfds, &select_timeout);
 827                }
 828        }
 829#else
 830        while (slot->in_use) {
 831                slot->curl_result = curl_easy_perform(slot->curl);
 832                finish_active_slot(slot);
 833        }
 834#endif
 835}
 836
 837static void release_active_slot(struct active_request_slot *slot)
 838{
 839        closedown_active_slot(slot);
 840        if (slot->curl && curl_session_count > min_curl_sessions) {
 841#ifdef USE_CURL_MULTI
 842                curl_multi_remove_handle(curlm, slot->curl);
 843#endif
 844                curl_easy_cleanup(slot->curl);
 845                slot->curl = NULL;
 846                curl_session_count--;
 847        }
 848#ifdef USE_CURL_MULTI
 849        fill_active_slots();
 850#endif
 851}
 852
 853void finish_all_active_slots(void)
 854{
 855        struct active_request_slot *slot = active_queue_head;
 856
 857        while (slot != NULL)
 858                if (slot->in_use) {
 859                        run_active_slot(slot);
 860                        slot = active_queue_head;
 861                } else {
 862                        slot = slot->next;
 863                }
 864}
 865
 866/* Helpers for modifying and creating URLs */
 867static inline int needs_quote(int ch)
 868{
 869        if (((ch >= 'A') && (ch <= 'Z'))
 870                        || ((ch >= 'a') && (ch <= 'z'))
 871                        || ((ch >= '0') && (ch <= '9'))
 872                        || (ch == '/')
 873                        || (ch == '-')
 874                        || (ch == '.'))
 875                return 0;
 876        return 1;
 877}
 878
 879static char *quote_ref_url(const char *base, const char *ref)
 880{
 881        struct strbuf buf = STRBUF_INIT;
 882        const char *cp;
 883        int ch;
 884
 885        end_url_with_slash(&buf, base);
 886
 887        for (cp = ref; (ch = *cp) != 0; cp++)
 888                if (needs_quote(ch))
 889                        strbuf_addf(&buf, "%%%02x", ch);
 890                else
 891                        strbuf_addch(&buf, *cp);
 892
 893        return strbuf_detach(&buf, NULL);
 894}
 895
 896void append_remote_object_url(struct strbuf *buf, const char *url,
 897                              const char *hex,
 898                              int only_two_digit_prefix)
 899{
 900        end_url_with_slash(buf, url);
 901
 902        strbuf_addf(buf, "objects/%.*s/", 2, hex);
 903        if (!only_two_digit_prefix)
 904                strbuf_addf(buf, "%s", hex+2);
 905}
 906
 907char *get_remote_object_url(const char *url, const char *hex,
 908                            int only_two_digit_prefix)
 909{
 910        struct strbuf buf = STRBUF_INIT;
 911        append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
 912        return strbuf_detach(&buf, NULL);
 913}
 914
 915static int handle_curl_result(struct slot_results *results)
 916{
 917        /*
 918         * If we see a failing http code with CURLE_OK, we have turned off
 919         * FAILONERROR (to keep the server's custom error response), and should
 920         * translate the code into failure here.
 921         */
 922        if (results->curl_result == CURLE_OK &&
 923            results->http_code >= 400) {
 924                results->curl_result = CURLE_HTTP_RETURNED_ERROR;
 925                /*
 926                 * Normally curl will already have put the "reason phrase"
 927                 * from the server into curl_errorstr; unfortunately without
 928                 * FAILONERROR it is lost, so we can give only the numeric
 929                 * status code.
 930                 */
 931                snprintf(curl_errorstr, sizeof(curl_errorstr),
 932                         "The requested URL returned error: %ld",
 933                         results->http_code);
 934        }
 935
 936        if (results->curl_result == CURLE_OK) {
 937                credential_approve(&http_auth);
 938                return HTTP_OK;
 939        } else if (missing_target(results))
 940                return HTTP_MISSING_TARGET;
 941        else if (results->http_code == 401) {
 942                if (http_auth.username && http_auth.password) {
 943                        credential_reject(&http_auth);
 944                        return HTTP_NOAUTH;
 945                } else {
 946#ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 947                        http_auth_methods &= ~CURLAUTH_GSSNEGOTIATE;
 948#endif
 949                        return HTTP_REAUTH;
 950                }
 951        } else {
 952#if LIBCURL_VERSION_NUM >= 0x070c00
 953                if (!curl_errorstr[0])
 954                        strlcpy(curl_errorstr,
 955                                curl_easy_strerror(results->curl_result),
 956                                sizeof(curl_errorstr));
 957#endif
 958                return HTTP_ERROR;
 959        }
 960}
 961
 962int run_one_slot(struct active_request_slot *slot,
 963                 struct slot_results *results)
 964{
 965        slot->results = results;
 966        if (!start_active_slot(slot)) {
 967                snprintf(curl_errorstr, sizeof(curl_errorstr),
 968                         "failed to start HTTP request");
 969                return HTTP_START_FAILED;
 970        }
 971
 972        run_active_slot(slot);
 973        return handle_curl_result(results);
 974}
 975
 976static CURLcode curlinfo_strbuf(CURL *curl, CURLINFO info, struct strbuf *buf)
 977{
 978        char *ptr;
 979        CURLcode ret;
 980
 981        strbuf_reset(buf);
 982        ret = curl_easy_getinfo(curl, info, &ptr);
 983        if (!ret && ptr)
 984                strbuf_addstr(buf, ptr);
 985        return ret;
 986}
 987
 988/*
 989 * Check for and extract a content-type parameter. "raw"
 990 * should be positioned at the start of the potential
 991 * parameter, with any whitespace already removed.
 992 *
 993 * "name" is the name of the parameter. The value is appended
 994 * to "out".
 995 */
 996static int extract_param(const char *raw, const char *name,
 997                         struct strbuf *out)
 998{
 999        size_t len = strlen(name);
1000
1001        if (strncasecmp(raw, name, len))
1002                return -1;
1003        raw += len;
1004
1005        if (*raw != '=')
1006                return -1;
1007        raw++;
1008
1009        while (*raw && !isspace(*raw) && *raw != ';')
1010                strbuf_addch(out, *raw++);
1011        return 0;
1012}
1013
1014/*
1015 * Extract a normalized version of the content type, with any
1016 * spaces suppressed, all letters lowercased, and no trailing ";"
1017 * or parameters.
1018 *
1019 * Note that we will silently remove even invalid whitespace. For
1020 * example, "text / plain" is specifically forbidden by RFC 2616,
1021 * but "text/plain" is the only reasonable output, and this keeps
1022 * our code simple.
1023 *
1024 * If the "charset" argument is not NULL, store the value of any
1025 * charset parameter there.
1026 *
1027 * Example:
1028 *   "TEXT/PLAIN; charset=utf-8" -> "text/plain", "utf-8"
1029 *   "text / plain" -> "text/plain"
1030 */
1031static void extract_content_type(struct strbuf *raw, struct strbuf *type,
1032                                 struct strbuf *charset)
1033{
1034        const char *p;
1035
1036        strbuf_reset(type);
1037        strbuf_grow(type, raw->len);
1038        for (p = raw->buf; *p; p++) {
1039                if (isspace(*p))
1040                        continue;
1041                if (*p == ';') {
1042                        p++;
1043                        break;
1044                }
1045                strbuf_addch(type, tolower(*p));
1046        }
1047
1048        if (!charset)
1049                return;
1050
1051        strbuf_reset(charset);
1052        while (*p) {
1053                while (isspace(*p) || *p == ';')
1054                        p++;
1055                if (!extract_param(p, "charset", charset))
1056                        return;
1057                while (*p && !isspace(*p))
1058                        p++;
1059        }
1060
1061        if (!charset->len && starts_with(type->buf, "text/"))
1062                strbuf_addstr(charset, "ISO-8859-1");
1063}
1064
1065static void write_accept_language(struct strbuf *buf)
1066{
1067        /*
1068         * MAX_DECIMAL_PLACES must not be larger than 3. If it is larger than
1069         * that, q-value will be smaller than 0.001, the minimum q-value the
1070         * HTTP specification allows. See
1071         * http://tools.ietf.org/html/rfc7231#section-5.3.1 for q-value.
1072         */
1073        const int MAX_DECIMAL_PLACES = 3;
1074        const int MAX_LANGUAGE_TAGS = 1000;
1075        const int MAX_ACCEPT_LANGUAGE_HEADER_SIZE = 4000;
1076        char **language_tags = NULL;
1077        int num_langs = 0;
1078        const char *s = get_preferred_languages();
1079        int i;
1080        struct strbuf tag = STRBUF_INIT;
1081
1082        /* Don't add Accept-Language header if no language is preferred. */
1083        if (!s)
1084                return;
1085
1086        /*
1087         * Split the colon-separated string of preferred languages into
1088         * language_tags array.
1089         */
1090        do {
1091                /* collect language tag */
1092                for (; *s && (isalnum(*s) || *s == '_'); s++)
1093                        strbuf_addch(&tag, *s == '_' ? '-' : *s);
1094
1095                /* skip .codeset, @modifier and any other unnecessary parts */
1096                while (*s && *s != ':')
1097                        s++;
1098
1099                if (tag.len) {
1100                        num_langs++;
1101                        REALLOC_ARRAY(language_tags, num_langs);
1102                        language_tags[num_langs - 1] = strbuf_detach(&tag, NULL);
1103                        if (num_langs >= MAX_LANGUAGE_TAGS - 1) /* -1 for '*' */
1104                                break;
1105                }
1106        } while (*s++);
1107
1108        /* write Accept-Language header into buf */
1109        if (num_langs) {
1110                int last_buf_len = 0;
1111                int max_q;
1112                int decimal_places;
1113                char q_format[32];
1114
1115                /* add '*' */
1116                REALLOC_ARRAY(language_tags, num_langs + 1);
1117                language_tags[num_langs++] = "*"; /* it's OK; this won't be freed */
1118
1119                /* compute decimal_places */
1120                for (max_q = 1, decimal_places = 0;
1121                     max_q < num_langs && decimal_places <= MAX_DECIMAL_PLACES;
1122                     decimal_places++, max_q *= 10)
1123                        ;
1124
1125                xsnprintf(q_format, sizeof(q_format), ";q=0.%%0%dd", decimal_places);
1126
1127                strbuf_addstr(buf, "Accept-Language: ");
1128
1129                for (i = 0; i < num_langs; i++) {
1130                        if (i > 0)
1131                                strbuf_addstr(buf, ", ");
1132
1133                        strbuf_addstr(buf, language_tags[i]);
1134
1135                        if (i > 0)
1136                                strbuf_addf(buf, q_format, max_q - i);
1137
1138                        if (buf->len > MAX_ACCEPT_LANGUAGE_HEADER_SIZE) {
1139                                strbuf_remove(buf, last_buf_len, buf->len - last_buf_len);
1140                                break;
1141                        }
1142
1143                        last_buf_len = buf->len;
1144                }
1145        }
1146
1147        /* free language tags -- last one is a static '*' */
1148        for (i = 0; i < num_langs - 1; i++)
1149                free(language_tags[i]);
1150        free(language_tags);
1151}
1152
1153/*
1154 * Get an Accept-Language header which indicates user's preferred languages.
1155 *
1156 * Examples:
1157 *   LANGUAGE= -> ""
1158 *   LANGUAGE=ko:en -> "Accept-Language: ko, en; q=0.9, *; q=0.1"
1159 *   LANGUAGE=ko_KR.UTF-8:sr@latin -> "Accept-Language: ko-KR, sr; q=0.9, *; q=0.1"
1160 *   LANGUAGE=ko LANG=en_US.UTF-8 -> "Accept-Language: ko, *; q=0.1"
1161 *   LANGUAGE= LANG=en_US.UTF-8 -> "Accept-Language: en-US, *; q=0.1"
1162 *   LANGUAGE= LANG=C -> ""
1163 */
1164static const char *get_accept_language(void)
1165{
1166        if (!cached_accept_language) {
1167                struct strbuf buf = STRBUF_INIT;
1168                write_accept_language(&buf);
1169                if (buf.len > 0)
1170                        cached_accept_language = strbuf_detach(&buf, NULL);
1171        }
1172
1173        return cached_accept_language;
1174}
1175
1176static void http_opt_request_remainder(CURL *curl, off_t pos)
1177{
1178        char buf[128];
1179        xsnprintf(buf, sizeof(buf), "%"PRIuMAX"-", (uintmax_t)pos);
1180        curl_easy_setopt(curl, CURLOPT_RANGE, buf);
1181}
1182
1183/* http_request() targets */
1184#define HTTP_REQUEST_STRBUF     0
1185#define HTTP_REQUEST_FILE       1
1186
1187static int http_request(const char *url,
1188                        void *result, int target,
1189                        const struct http_get_options *options)
1190{
1191        struct active_request_slot *slot;
1192        struct slot_results results;
1193        struct curl_slist *headers = NULL;
1194        struct strbuf buf = STRBUF_INIT;
1195        const char *accept_language;
1196        int ret;
1197
1198        slot = get_active_slot();
1199        curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1200
1201        if (result == NULL) {
1202                curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
1203        } else {
1204                curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
1205                curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
1206
1207                if (target == HTTP_REQUEST_FILE) {
1208                        off_t posn = ftello(result);
1209                        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1210                                         fwrite);
1211                        if (posn > 0)
1212                                http_opt_request_remainder(slot->curl, posn);
1213                } else
1214                        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1215                                         fwrite_buffer);
1216        }
1217
1218        accept_language = get_accept_language();
1219
1220        if (accept_language)
1221                headers = curl_slist_append(headers, accept_language);
1222
1223        strbuf_addstr(&buf, "Pragma:");
1224        if (options && options->no_cache)
1225                strbuf_addstr(&buf, " no-cache");
1226        if (options && options->keep_error)
1227                curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
1228
1229        headers = curl_slist_append(headers, buf.buf);
1230
1231        curl_easy_setopt(slot->curl, CURLOPT_URL, url);
1232        curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
1233        curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "gzip");
1234
1235        ret = run_one_slot(slot, &results);
1236
1237        if (options && options->content_type) {
1238                struct strbuf raw = STRBUF_INIT;
1239                curlinfo_strbuf(slot->curl, CURLINFO_CONTENT_TYPE, &raw);
1240                extract_content_type(&raw, options->content_type,
1241                                     options->charset);
1242                strbuf_release(&raw);
1243        }
1244
1245        if (options && options->effective_url)
1246                curlinfo_strbuf(slot->curl, CURLINFO_EFFECTIVE_URL,
1247                                options->effective_url);
1248
1249        curl_slist_free_all(headers);
1250        strbuf_release(&buf);
1251
1252        return ret;
1253}
1254
1255/*
1256 * Update the "base" url to a more appropriate value, as deduced by
1257 * redirects seen when requesting a URL starting with "url".
1258 *
1259 * The "asked" parameter is a URL that we asked curl to access, and must begin
1260 * with "base".
1261 *
1262 * The "got" parameter is the URL that curl reported to us as where we ended
1263 * up.
1264 *
1265 * Returns 1 if we updated the base url, 0 otherwise.
1266 *
1267 * Our basic strategy is to compare "base" and "asked" to find the bits
1268 * specific to our request. We then strip those bits off of "got" to yield the
1269 * new base. So for example, if our base is "http://example.com/foo.git",
1270 * and we ask for "http://example.com/foo.git/info/refs", we might end up
1271 * with "https://other.example.com/foo.git/info/refs". We would want the
1272 * new URL to become "https://other.example.com/foo.git".
1273 *
1274 * Note that this assumes a sane redirect scheme. It's entirely possible
1275 * in the example above to end up at a URL that does not even end in
1276 * "info/refs".  In such a case we simply punt, as there is not much we can
1277 * do (and such a scheme is unlikely to represent a real git repository,
1278 * which means we are likely about to abort anyway).
1279 */
1280static int update_url_from_redirect(struct strbuf *base,
1281                                    const char *asked,
1282                                    const struct strbuf *got)
1283{
1284        const char *tail;
1285        size_t tail_len;
1286
1287        if (!strcmp(asked, got->buf))
1288                return 0;
1289
1290        if (!skip_prefix(asked, base->buf, &tail))
1291                die("BUG: update_url_from_redirect: %s is not a superset of %s",
1292                    asked, base->buf);
1293
1294        tail_len = strlen(tail);
1295
1296        if (got->len < tail_len ||
1297            strcmp(tail, got->buf + got->len - tail_len))
1298                return 0; /* insane redirect scheme */
1299
1300        strbuf_reset(base);
1301        strbuf_add(base, got->buf, got->len - tail_len);
1302        return 1;
1303}
1304
1305static int http_request_reauth(const char *url,
1306                               void *result, int target,
1307                               struct http_get_options *options)
1308{
1309        int ret = http_request(url, result, target, options);
1310
1311        if (options && options->effective_url && options->base_url) {
1312                if (update_url_from_redirect(options->base_url,
1313                                             url, options->effective_url)) {
1314                        credential_from_url(&http_auth, options->base_url->buf);
1315                        url = options->effective_url->buf;
1316                }
1317        }
1318
1319        if (ret != HTTP_REAUTH)
1320                return ret;
1321
1322        /*
1323         * If we are using KEEP_ERROR, the previous request may have
1324         * put cruft into our output stream; we should clear it out before
1325         * making our next request. We only know how to do this for
1326         * the strbuf case, but that is enough to satisfy current callers.
1327         */
1328        if (options && options->keep_error) {
1329                switch (target) {
1330                case HTTP_REQUEST_STRBUF:
1331                        strbuf_reset(result);
1332                        break;
1333                default:
1334                        die("BUG: HTTP_KEEP_ERROR is only supported with strbufs");
1335                }
1336        }
1337
1338        credential_fill(&http_auth);
1339
1340        return http_request(url, result, target, options);
1341}
1342
1343int http_get_strbuf(const char *url,
1344                    struct strbuf *result,
1345                    struct http_get_options *options)
1346{
1347        return http_request_reauth(url, result, HTTP_REQUEST_STRBUF, options);
1348}
1349
1350/*
1351 * Downloads a URL and stores the result in the given file.
1352 *
1353 * If a previous interrupted download is detected (i.e. a previous temporary
1354 * file is still around) the download is resumed.
1355 */
1356static int http_get_file(const char *url, const char *filename,
1357                         struct http_get_options *options)
1358{
1359        int ret;
1360        struct strbuf tmpfile = STRBUF_INIT;
1361        FILE *result;
1362
1363        strbuf_addf(&tmpfile, "%s.temp", filename);
1364        result = fopen(tmpfile.buf, "a");
1365        if (!result) {
1366                error("Unable to open local file %s", tmpfile.buf);
1367                ret = HTTP_ERROR;
1368                goto cleanup;
1369        }
1370
1371        ret = http_request_reauth(url, result, HTTP_REQUEST_FILE, options);
1372        fclose(result);
1373
1374        if (ret == HTTP_OK && finalize_object_file(tmpfile.buf, filename))
1375                ret = HTTP_ERROR;
1376cleanup:
1377        strbuf_release(&tmpfile);
1378        return ret;
1379}
1380
1381int http_fetch_ref(const char *base, struct ref *ref)
1382{
1383        struct http_get_options options = {0};
1384        char *url;
1385        struct strbuf buffer = STRBUF_INIT;
1386        int ret = -1;
1387
1388        options.no_cache = 1;
1389
1390        url = quote_ref_url(base, ref->name);
1391        if (http_get_strbuf(url, &buffer, &options) == HTTP_OK) {
1392                strbuf_rtrim(&buffer);
1393                if (buffer.len == 40)
1394                        ret = get_sha1_hex(buffer.buf, ref->old_sha1);
1395                else if (starts_with(buffer.buf, "ref: ")) {
1396                        ref->symref = xstrdup(buffer.buf + 5);
1397                        ret = 0;
1398                }
1399        }
1400
1401        strbuf_release(&buffer);
1402        free(url);
1403        return ret;
1404}
1405
1406/* Helpers for fetching packs */
1407static char *fetch_pack_index(unsigned char *sha1, const char *base_url)
1408{
1409        char *url, *tmp;
1410        struct strbuf buf = STRBUF_INIT;
1411
1412        if (http_is_verbose)
1413                fprintf(stderr, "Getting index for pack %s\n", sha1_to_hex(sha1));
1414
1415        end_url_with_slash(&buf, base_url);
1416        strbuf_addf(&buf, "objects/pack/pack-%s.idx", sha1_to_hex(sha1));
1417        url = strbuf_detach(&buf, NULL);
1418
1419        strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(sha1));
1420        tmp = strbuf_detach(&buf, NULL);
1421
1422        if (http_get_file(url, tmp, NULL) != HTTP_OK) {
1423                error("Unable to get pack index %s", url);
1424                free(tmp);
1425                tmp = NULL;
1426        }
1427
1428        free(url);
1429        return tmp;
1430}
1431
1432static int fetch_and_setup_pack_index(struct packed_git **packs_head,
1433        unsigned char *sha1, const char *base_url)
1434{
1435        struct packed_git *new_pack;
1436        char *tmp_idx = NULL;
1437        int ret;
1438
1439        if (has_pack_index(sha1)) {
1440                new_pack = parse_pack_index(sha1, sha1_pack_index_name(sha1));
1441                if (!new_pack)
1442                        return -1; /* parse_pack_index() already issued error message */
1443                goto add_pack;
1444        }
1445
1446        tmp_idx = fetch_pack_index(sha1, base_url);
1447        if (!tmp_idx)
1448                return -1;
1449
1450        new_pack = parse_pack_index(sha1, tmp_idx);
1451        if (!new_pack) {
1452                unlink(tmp_idx);
1453                free(tmp_idx);
1454
1455                return -1; /* parse_pack_index() already issued error message */
1456        }
1457
1458        ret = verify_pack_index(new_pack);
1459        if (!ret) {
1460                close_pack_index(new_pack);
1461                ret = finalize_object_file(tmp_idx, sha1_pack_index_name(sha1));
1462        }
1463        free(tmp_idx);
1464        if (ret)
1465                return -1;
1466
1467add_pack:
1468        new_pack->next = *packs_head;
1469        *packs_head = new_pack;
1470        return 0;
1471}
1472
1473int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
1474{
1475        struct http_get_options options = {0};
1476        int ret = 0, i = 0;
1477        char *url, *data;
1478        struct strbuf buf = STRBUF_INIT;
1479        unsigned char sha1[20];
1480
1481        end_url_with_slash(&buf, base_url);
1482        strbuf_addstr(&buf, "objects/info/packs");
1483        url = strbuf_detach(&buf, NULL);
1484
1485        options.no_cache = 1;
1486        ret = http_get_strbuf(url, &buf, &options);
1487        if (ret != HTTP_OK)
1488                goto cleanup;
1489
1490        data = buf.buf;
1491        while (i < buf.len) {
1492                switch (data[i]) {
1493                case 'P':
1494                        i++;
1495                        if (i + 52 <= buf.len &&
1496                            starts_with(data + i, " pack-") &&
1497                            starts_with(data + i + 46, ".pack\n")) {
1498                                get_sha1_hex(data + i + 6, sha1);
1499                                fetch_and_setup_pack_index(packs_head, sha1,
1500                                                      base_url);
1501                                i += 51;
1502                                break;
1503                        }
1504                default:
1505                        while (i < buf.len && data[i] != '\n')
1506                                i++;
1507                }
1508                i++;
1509        }
1510
1511cleanup:
1512        free(url);
1513        return ret;
1514}
1515
1516void release_http_pack_request(struct http_pack_request *preq)
1517{
1518        if (preq->packfile != NULL) {
1519                fclose(preq->packfile);
1520                preq->packfile = NULL;
1521        }
1522        preq->slot = NULL;
1523        free(preq->url);
1524        free(preq);
1525}
1526
1527int finish_http_pack_request(struct http_pack_request *preq)
1528{
1529        struct packed_git **lst;
1530        struct packed_git *p = preq->target;
1531        char *tmp_idx;
1532        size_t len;
1533        struct child_process ip = CHILD_PROCESS_INIT;
1534        const char *ip_argv[8];
1535
1536        close_pack_index(p);
1537
1538        fclose(preq->packfile);
1539        preq->packfile = NULL;
1540
1541        lst = preq->lst;
1542        while (*lst != p)
1543                lst = &((*lst)->next);
1544        *lst = (*lst)->next;
1545
1546        if (!strip_suffix(preq->tmpfile, ".pack.temp", &len))
1547                die("BUG: pack tmpfile does not end in .pack.temp?");
1548        tmp_idx = xstrfmt("%.*s.idx.temp", (int)len, preq->tmpfile);
1549
1550        ip_argv[0] = "index-pack";
1551        ip_argv[1] = "-o";
1552        ip_argv[2] = tmp_idx;
1553        ip_argv[3] = preq->tmpfile;
1554        ip_argv[4] = NULL;
1555
1556        ip.argv = ip_argv;
1557        ip.git_cmd = 1;
1558        ip.no_stdin = 1;
1559        ip.no_stdout = 1;
1560
1561        if (run_command(&ip)) {
1562                unlink(preq->tmpfile);
1563                unlink(tmp_idx);
1564                free(tmp_idx);
1565                return -1;
1566        }
1567
1568        unlink(sha1_pack_index_name(p->sha1));
1569
1570        if (finalize_object_file(preq->tmpfile, sha1_pack_name(p->sha1))
1571         || finalize_object_file(tmp_idx, sha1_pack_index_name(p->sha1))) {
1572                free(tmp_idx);
1573                return -1;
1574        }
1575
1576        install_packed_git(p);
1577        free(tmp_idx);
1578        return 0;
1579}
1580
1581struct http_pack_request *new_http_pack_request(
1582        struct packed_git *target, const char *base_url)
1583{
1584        off_t prev_posn = 0;
1585        struct strbuf buf = STRBUF_INIT;
1586        struct http_pack_request *preq;
1587
1588        preq = xcalloc(1, sizeof(*preq));
1589        preq->target = target;
1590
1591        end_url_with_slash(&buf, base_url);
1592        strbuf_addf(&buf, "objects/pack/pack-%s.pack",
1593                sha1_to_hex(target->sha1));
1594        preq->url = strbuf_detach(&buf, NULL);
1595
1596        snprintf(preq->tmpfile, sizeof(preq->tmpfile), "%s.temp",
1597                sha1_pack_name(target->sha1));
1598        preq->packfile = fopen(preq->tmpfile, "a");
1599        if (!preq->packfile) {
1600                error("Unable to open local file %s for pack",
1601                      preq->tmpfile);
1602                goto abort;
1603        }
1604
1605        preq->slot = get_active_slot();
1606        curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
1607        curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
1608        curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
1609        curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1610                no_pragma_header);
1611
1612        /*
1613         * If there is data present from a previous transfer attempt,
1614         * resume where it left off
1615         */
1616        prev_posn = ftello(preq->packfile);
1617        if (prev_posn>0) {
1618                if (http_is_verbose)
1619                        fprintf(stderr,
1620                                "Resuming fetch of pack %s at byte %ld\n",
1621                                sha1_to_hex(target->sha1), prev_posn);
1622                http_opt_request_remainder(preq->slot->curl, prev_posn);
1623        }
1624
1625        return preq;
1626
1627abort:
1628        free(preq->url);
1629        free(preq);
1630        return NULL;
1631}
1632
1633/* Helpers for fetching objects (loose) */
1634static size_t fwrite_sha1_file(char *ptr, size_t eltsize, size_t nmemb,
1635                               void *data)
1636{
1637        unsigned char expn[4096];
1638        size_t size = eltsize * nmemb;
1639        int posn = 0;
1640        struct http_object_request *freq =
1641                (struct http_object_request *)data;
1642        do {
1643                ssize_t retval = xwrite(freq->localfile,
1644                                        (char *) ptr + posn, size - posn);
1645                if (retval < 0)
1646                        return posn;
1647                posn += retval;
1648        } while (posn < size);
1649
1650        freq->stream.avail_in = size;
1651        freq->stream.next_in = (void *)ptr;
1652        do {
1653                freq->stream.next_out = expn;
1654                freq->stream.avail_out = sizeof(expn);
1655                freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
1656                git_SHA1_Update(&freq->c, expn,
1657                                sizeof(expn) - freq->stream.avail_out);
1658        } while (freq->stream.avail_in && freq->zret == Z_OK);
1659        return size;
1660}
1661
1662struct http_object_request *new_http_object_request(const char *base_url,
1663        unsigned char *sha1)
1664{
1665        char *hex = sha1_to_hex(sha1);
1666        const char *filename;
1667        char prevfile[PATH_MAX];
1668        int prevlocal;
1669        char prev_buf[PREV_BUF_SIZE];
1670        ssize_t prev_read = 0;
1671        off_t prev_posn = 0;
1672        struct http_object_request *freq;
1673
1674        freq = xcalloc(1, sizeof(*freq));
1675        hashcpy(freq->sha1, sha1);
1676        freq->localfile = -1;
1677
1678        filename = sha1_file_name(sha1);
1679        snprintf(freq->tmpfile, sizeof(freq->tmpfile),
1680                 "%s.temp", filename);
1681
1682        snprintf(prevfile, sizeof(prevfile), "%s.prev", filename);
1683        unlink_or_warn(prevfile);
1684        rename(freq->tmpfile, prevfile);
1685        unlink_or_warn(freq->tmpfile);
1686
1687        if (freq->localfile != -1)
1688                error("fd leakage in start: %d", freq->localfile);
1689        freq->localfile = open(freq->tmpfile,
1690                               O_WRONLY | O_CREAT | O_EXCL, 0666);
1691        /*
1692         * This could have failed due to the "lazy directory creation";
1693         * try to mkdir the last path component.
1694         */
1695        if (freq->localfile < 0 && errno == ENOENT) {
1696                char *dir = strrchr(freq->tmpfile, '/');
1697                if (dir) {
1698                        *dir = 0;
1699                        mkdir(freq->tmpfile, 0777);
1700                        *dir = '/';
1701                }
1702                freq->localfile = open(freq->tmpfile,
1703                                       O_WRONLY | O_CREAT | O_EXCL, 0666);
1704        }
1705
1706        if (freq->localfile < 0) {
1707                error("Couldn't create temporary file %s: %s",
1708                      freq->tmpfile, strerror(errno));
1709                goto abort;
1710        }
1711
1712        git_inflate_init(&freq->stream);
1713
1714        git_SHA1_Init(&freq->c);
1715
1716        freq->url = get_remote_object_url(base_url, hex, 0);
1717
1718        /*
1719         * If a previous temp file is present, process what was already
1720         * fetched.
1721         */
1722        prevlocal = open(prevfile, O_RDONLY);
1723        if (prevlocal != -1) {
1724                do {
1725                        prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
1726                        if (prev_read>0) {
1727                                if (fwrite_sha1_file(prev_buf,
1728                                                     1,
1729                                                     prev_read,
1730                                                     freq) == prev_read) {
1731                                        prev_posn += prev_read;
1732                                } else {
1733                                        prev_read = -1;
1734                                }
1735                        }
1736                } while (prev_read > 0);
1737                close(prevlocal);
1738        }
1739        unlink_or_warn(prevfile);
1740
1741        /*
1742         * Reset inflate/SHA1 if there was an error reading the previous temp
1743         * file; also rewind to the beginning of the local file.
1744         */
1745        if (prev_read == -1) {
1746                memset(&freq->stream, 0, sizeof(freq->stream));
1747                git_inflate_init(&freq->stream);
1748                git_SHA1_Init(&freq->c);
1749                if (prev_posn>0) {
1750                        prev_posn = 0;
1751                        lseek(freq->localfile, 0, SEEK_SET);
1752                        if (ftruncate(freq->localfile, 0) < 0) {
1753                                error("Couldn't truncate temporary file %s: %s",
1754                                          freq->tmpfile, strerror(errno));
1755                                goto abort;
1756                        }
1757                }
1758        }
1759
1760        freq->slot = get_active_slot();
1761
1762        curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
1763        curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
1764        curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
1765        curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
1766        curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
1767
1768        /*
1769         * If we have successfully processed data from a previous fetch
1770         * attempt, only fetch the data we don't already have.
1771         */
1772        if (prev_posn>0) {
1773                if (http_is_verbose)
1774                        fprintf(stderr,
1775                                "Resuming fetch of object %s at byte %ld\n",
1776                                hex, prev_posn);
1777                http_opt_request_remainder(freq->slot->curl, prev_posn);
1778        }
1779
1780        return freq;
1781
1782abort:
1783        free(freq->url);
1784        free(freq);
1785        return NULL;
1786}
1787
1788void process_http_object_request(struct http_object_request *freq)
1789{
1790        if (freq->slot == NULL)
1791                return;
1792        freq->curl_result = freq->slot->curl_result;
1793        freq->http_code = freq->slot->http_code;
1794        freq->slot = NULL;
1795}
1796
1797int finish_http_object_request(struct http_object_request *freq)
1798{
1799        struct stat st;
1800
1801        close(freq->localfile);
1802        freq->localfile = -1;
1803
1804        process_http_object_request(freq);
1805
1806        if (freq->http_code == 416) {
1807                warning("requested range invalid; we may already have all the data.");
1808        } else if (freq->curl_result != CURLE_OK) {
1809                if (stat(freq->tmpfile, &st) == 0)
1810                        if (st.st_size == 0)
1811                                unlink_or_warn(freq->tmpfile);
1812                return -1;
1813        }
1814
1815        git_inflate_end(&freq->stream);
1816        git_SHA1_Final(freq->real_sha1, &freq->c);
1817        if (freq->zret != Z_STREAM_END) {
1818                unlink_or_warn(freq->tmpfile);
1819                return -1;
1820        }
1821        if (hashcmp(freq->sha1, freq->real_sha1)) {
1822                unlink_or_warn(freq->tmpfile);
1823                return -1;
1824        }
1825        freq->rename =
1826                finalize_object_file(freq->tmpfile, sha1_file_name(freq->sha1));
1827
1828        return freq->rename;
1829}
1830
1831void abort_http_object_request(struct http_object_request *freq)
1832{
1833        unlink_or_warn(freq->tmpfile);
1834
1835        release_http_object_request(freq);
1836}
1837
1838void release_http_object_request(struct http_object_request *freq)
1839{
1840        if (freq->localfile != -1) {
1841                close(freq->localfile);
1842                freq->localfile = -1;
1843        }
1844        if (freq->url != NULL) {
1845                free(freq->url);
1846                freq->url = NULL;
1847        }
1848        if (freq->slot != NULL) {
1849                freq->slot->callback_func = NULL;
1850                freq->slot->callback_data = NULL;
1851                release_active_slot(freq->slot);
1852                freq->slot = NULL;
1853        }
1854}