http.con commit cleanups: ensure that git-compat-util.h is included first (1c4b660)
   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 (!curl_ssl_verify) {
 305                curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
 306                curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
 307        } else {
 308                /* Verify authenticity of the peer's certificate */
 309                curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
 310                /* The name in the cert must match whom we tried to connect */
 311                curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
 312        }
 313
 314#if LIBCURL_VERSION_NUM >= 0x070907
 315        curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
 316#endif
 317#ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 318        curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 319#endif
 320
 321        if (http_proactive_auth)
 322                init_curl_http_auth(result);
 323
 324        if (ssl_cert != NULL)
 325                curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
 326        if (has_cert_password())
 327                curl_easy_setopt(result, CURLOPT_KEYPASSWD, cert_auth.password);
 328#if LIBCURL_VERSION_NUM >= 0x070903
 329        if (ssl_key != NULL)
 330                curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
 331#endif
 332#if LIBCURL_VERSION_NUM >= 0x070908
 333        if (ssl_capath != NULL)
 334                curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
 335#endif
 336        if (ssl_cainfo != NULL)
 337                curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
 338
 339        if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
 340                curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
 341                                 curl_low_speed_limit);
 342                curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
 343                                 curl_low_speed_time);
 344        }
 345
 346        curl_easy_setopt(result, CURLOPT_FOLLOWLOCATION, 1);
 347#if LIBCURL_VERSION_NUM >= 0x071301
 348        curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
 349#elif LIBCURL_VERSION_NUM >= 0x071101
 350        curl_easy_setopt(result, CURLOPT_POST301, 1);
 351#endif
 352
 353        if (getenv("GIT_CURL_VERBOSE"))
 354                curl_easy_setopt(result, CURLOPT_VERBOSE, 1);
 355
 356        curl_easy_setopt(result, CURLOPT_USERAGENT,
 357                user_agent ? user_agent : git_user_agent());
 358
 359        if (curl_ftp_no_epsv)
 360                curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
 361
 362#ifdef CURLOPT_USE_SSL
 363        if (curl_ssl_try)
 364                curl_easy_setopt(result, CURLOPT_USE_SSL, CURLUSESSL_TRY);
 365#endif
 366
 367        if (curl_http_proxy) {
 368                curl_easy_setopt(result, CURLOPT_PROXY, curl_http_proxy);
 369                curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 370        }
 371
 372        set_curl_keepalive(result);
 373
 374        return result;
 375}
 376
 377static void set_from_env(const char **var, const char *envname)
 378{
 379        const char *val = getenv(envname);
 380        if (val)
 381                *var = val;
 382}
 383
 384void http_init(struct remote *remote, const char *url, int proactive_auth)
 385{
 386        char *low_speed_limit;
 387        char *low_speed_time;
 388        char *normalized_url;
 389        struct urlmatch_config config = { STRING_LIST_INIT_DUP };
 390
 391        config.section = "http";
 392        config.key = NULL;
 393        config.collect_fn = http_options;
 394        config.cascade_fn = git_default_config;
 395        config.cb = NULL;
 396
 397        http_is_verbose = 0;
 398        normalized_url = url_normalize(url, &config.url);
 399
 400        git_config(urlmatch_config_entry, &config);
 401        free(normalized_url);
 402
 403        curl_global_init(CURL_GLOBAL_ALL);
 404
 405        http_proactive_auth = proactive_auth;
 406
 407        if (remote && remote->http_proxy)
 408                curl_http_proxy = xstrdup(remote->http_proxy);
 409
 410        pragma_header = curl_slist_append(pragma_header, "Pragma: no-cache");
 411        no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
 412
 413#ifdef USE_CURL_MULTI
 414        {
 415                char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
 416                if (http_max_requests != NULL)
 417                        max_requests = atoi(http_max_requests);
 418        }
 419
 420        curlm = curl_multi_init();
 421        if (curlm == NULL) {
 422                fprintf(stderr, "Error creating curl multi handle.\n");
 423                exit(1);
 424        }
 425#endif
 426
 427        if (getenv("GIT_SSL_NO_VERIFY"))
 428                curl_ssl_verify = 0;
 429
 430        set_from_env(&ssl_cert, "GIT_SSL_CERT");
 431#if LIBCURL_VERSION_NUM >= 0x070903
 432        set_from_env(&ssl_key, "GIT_SSL_KEY");
 433#endif
 434#if LIBCURL_VERSION_NUM >= 0x070908
 435        set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
 436#endif
 437        set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
 438
 439        set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
 440
 441        low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
 442        if (low_speed_limit != NULL)
 443                curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
 444        low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
 445        if (low_speed_time != NULL)
 446                curl_low_speed_time = strtol(low_speed_time, NULL, 10);
 447
 448        if (curl_ssl_verify == -1)
 449                curl_ssl_verify = 1;
 450
 451        curl_session_count = 0;
 452#ifdef USE_CURL_MULTI
 453        if (max_requests < 1)
 454                max_requests = DEFAULT_MAX_REQUESTS;
 455#endif
 456
 457        if (getenv("GIT_CURL_FTP_NO_EPSV"))
 458                curl_ftp_no_epsv = 1;
 459
 460        if (url) {
 461                credential_from_url(&http_auth, url);
 462                if (!ssl_cert_password_required &&
 463                    getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
 464                    starts_with(url, "https://"))
 465                        ssl_cert_password_required = 1;
 466        }
 467
 468#ifndef NO_CURL_EASY_DUPHANDLE
 469        curl_default = get_curl_handle();
 470#endif
 471}
 472
 473void http_cleanup(void)
 474{
 475        struct active_request_slot *slot = active_queue_head;
 476
 477        while (slot != NULL) {
 478                struct active_request_slot *next = slot->next;
 479                if (slot->curl != NULL) {
 480#ifdef USE_CURL_MULTI
 481                        curl_multi_remove_handle(curlm, slot->curl);
 482#endif
 483                        curl_easy_cleanup(slot->curl);
 484                }
 485                free(slot);
 486                slot = next;
 487        }
 488        active_queue_head = NULL;
 489
 490#ifndef NO_CURL_EASY_DUPHANDLE
 491        curl_easy_cleanup(curl_default);
 492#endif
 493
 494#ifdef USE_CURL_MULTI
 495        curl_multi_cleanup(curlm);
 496#endif
 497        curl_global_cleanup();
 498
 499        curl_slist_free_all(pragma_header);
 500        pragma_header = NULL;
 501
 502        curl_slist_free_all(no_pragma_header);
 503        no_pragma_header = NULL;
 504
 505        if (curl_http_proxy) {
 506                free((void *)curl_http_proxy);
 507                curl_http_proxy = NULL;
 508        }
 509
 510        if (cert_auth.password != NULL) {
 511                memset(cert_auth.password, 0, strlen(cert_auth.password));
 512                free(cert_auth.password);
 513                cert_auth.password = NULL;
 514        }
 515        ssl_cert_password_required = 0;
 516}
 517
 518struct active_request_slot *get_active_slot(void)
 519{
 520        struct active_request_slot *slot = active_queue_head;
 521        struct active_request_slot *newslot;
 522
 523#ifdef USE_CURL_MULTI
 524        int num_transfers;
 525
 526        /* Wait for a slot to open up if the queue is full */
 527        while (active_requests >= max_requests) {
 528                curl_multi_perform(curlm, &num_transfers);
 529                if (num_transfers < active_requests)
 530                        process_curl_messages();
 531        }
 532#endif
 533
 534        while (slot != NULL && slot->in_use)
 535                slot = slot->next;
 536
 537        if (slot == NULL) {
 538                newslot = xmalloc(sizeof(*newslot));
 539                newslot->curl = NULL;
 540                newslot->in_use = 0;
 541                newslot->next = NULL;
 542
 543                slot = active_queue_head;
 544                if (slot == NULL) {
 545                        active_queue_head = newslot;
 546                } else {
 547                        while (slot->next != NULL)
 548                                slot = slot->next;
 549                        slot->next = newslot;
 550                }
 551                slot = newslot;
 552        }
 553
 554        if (slot->curl == NULL) {
 555#ifdef NO_CURL_EASY_DUPHANDLE
 556                slot->curl = get_curl_handle();
 557#else
 558                slot->curl = curl_easy_duphandle(curl_default);
 559#endif
 560                curl_session_count++;
 561        }
 562
 563        active_requests++;
 564        slot->in_use = 1;
 565        slot->results = NULL;
 566        slot->finished = NULL;
 567        slot->callback_data = NULL;
 568        slot->callback_func = NULL;
 569        curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
 570        if (curl_save_cookies)
 571                curl_easy_setopt(slot->curl, CURLOPT_COOKIEJAR, curl_cookie_file);
 572        curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
 573        curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
 574        curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
 575        curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
 576        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
 577        curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
 578        curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
 579        curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 580        curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 1);
 581        if (http_auth.password)
 582                init_curl_http_auth(slot->curl);
 583
 584        return slot;
 585}
 586
 587int start_active_slot(struct active_request_slot *slot)
 588{
 589#ifdef USE_CURL_MULTI
 590        CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
 591        int num_transfers;
 592
 593        if (curlm_result != CURLM_OK &&
 594            curlm_result != CURLM_CALL_MULTI_PERFORM) {
 595                active_requests--;
 596                slot->in_use = 0;
 597                return 0;
 598        }
 599
 600        /*
 601         * We know there must be something to do, since we just added
 602         * something.
 603         */
 604        curl_multi_perform(curlm, &num_transfers);
 605#endif
 606        return 1;
 607}
 608
 609#ifdef USE_CURL_MULTI
 610struct fill_chain {
 611        void *data;
 612        int (*fill)(void *);
 613        struct fill_chain *next;
 614};
 615
 616static struct fill_chain *fill_cfg;
 617
 618void add_fill_function(void *data, int (*fill)(void *))
 619{
 620        struct fill_chain *new = xmalloc(sizeof(*new));
 621        struct fill_chain **linkp = &fill_cfg;
 622        new->data = data;
 623        new->fill = fill;
 624        new->next = NULL;
 625        while (*linkp)
 626                linkp = &(*linkp)->next;
 627        *linkp = new;
 628}
 629
 630void fill_active_slots(void)
 631{
 632        struct active_request_slot *slot = active_queue_head;
 633
 634        while (active_requests < max_requests) {
 635                struct fill_chain *fill;
 636                for (fill = fill_cfg; fill; fill = fill->next)
 637                        if (fill->fill(fill->data))
 638                                break;
 639
 640                if (!fill)
 641                        break;
 642        }
 643
 644        while (slot != NULL) {
 645                if (!slot->in_use && slot->curl != NULL
 646                        && curl_session_count > min_curl_sessions) {
 647                        curl_easy_cleanup(slot->curl);
 648                        slot->curl = NULL;
 649                        curl_session_count--;
 650                }
 651                slot = slot->next;
 652        }
 653}
 654
 655void step_active_slots(void)
 656{
 657        int num_transfers;
 658        CURLMcode curlm_result;
 659
 660        do {
 661                curlm_result = curl_multi_perform(curlm, &num_transfers);
 662        } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
 663        if (num_transfers < active_requests) {
 664                process_curl_messages();
 665                fill_active_slots();
 666        }
 667}
 668#endif
 669
 670void run_active_slot(struct active_request_slot *slot)
 671{
 672#ifdef USE_CURL_MULTI
 673        fd_set readfds;
 674        fd_set writefds;
 675        fd_set excfds;
 676        int max_fd;
 677        struct timeval select_timeout;
 678        int finished = 0;
 679
 680        slot->finished = &finished;
 681        while (!finished) {
 682                step_active_slots();
 683
 684                if (slot->in_use) {
 685#if LIBCURL_VERSION_NUM >= 0x070f04
 686                        long curl_timeout;
 687                        curl_multi_timeout(curlm, &curl_timeout);
 688                        if (curl_timeout == 0) {
 689                                continue;
 690                        } else if (curl_timeout == -1) {
 691                                select_timeout.tv_sec  = 0;
 692                                select_timeout.tv_usec = 50000;
 693                        } else {
 694                                select_timeout.tv_sec  =  curl_timeout / 1000;
 695                                select_timeout.tv_usec = (curl_timeout % 1000) * 1000;
 696                        }
 697#else
 698                        select_timeout.tv_sec  = 0;
 699                        select_timeout.tv_usec = 50000;
 700#endif
 701
 702                        max_fd = -1;
 703                        FD_ZERO(&readfds);
 704                        FD_ZERO(&writefds);
 705                        FD_ZERO(&excfds);
 706                        curl_multi_fdset(curlm, &readfds, &writefds, &excfds, &max_fd);
 707
 708                        /*
 709                         * It can happen that curl_multi_timeout returns a pathologically
 710                         * long timeout when curl_multi_fdset returns no file descriptors
 711                         * to read.  See commit message for more details.
 712                         */
 713                        if (max_fd < 0 &&
 714                            (select_timeout.tv_sec > 0 ||
 715                             select_timeout.tv_usec > 50000)) {
 716                                select_timeout.tv_sec  = 0;
 717                                select_timeout.tv_usec = 50000;
 718                        }
 719
 720                        select(max_fd+1, &readfds, &writefds, &excfds, &select_timeout);
 721                }
 722        }
 723#else
 724        while (slot->in_use) {
 725                slot->curl_result = curl_easy_perform(slot->curl);
 726                finish_active_slot(slot);
 727        }
 728#endif
 729}
 730
 731static void closedown_active_slot(struct active_request_slot *slot)
 732{
 733        active_requests--;
 734        slot->in_use = 0;
 735}
 736
 737static void release_active_slot(struct active_request_slot *slot)
 738{
 739        closedown_active_slot(slot);
 740        if (slot->curl && curl_session_count > min_curl_sessions) {
 741#ifdef USE_CURL_MULTI
 742                curl_multi_remove_handle(curlm, slot->curl);
 743#endif
 744                curl_easy_cleanup(slot->curl);
 745                slot->curl = NULL;
 746                curl_session_count--;
 747        }
 748#ifdef USE_CURL_MULTI
 749        fill_active_slots();
 750#endif
 751}
 752
 753void finish_active_slot(struct active_request_slot *slot)
 754{
 755        closedown_active_slot(slot);
 756        curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
 757
 758        if (slot->finished != NULL)
 759                (*slot->finished) = 1;
 760
 761        /* Store slot results so they can be read after the slot is reused */
 762        if (slot->results != NULL) {
 763                slot->results->curl_result = slot->curl_result;
 764                slot->results->http_code = slot->http_code;
 765#if LIBCURL_VERSION_NUM >= 0x070a08
 766                curl_easy_getinfo(slot->curl, CURLINFO_HTTPAUTH_AVAIL,
 767                                  &slot->results->auth_avail);
 768#else
 769                slot->results->auth_avail = 0;
 770#endif
 771        }
 772
 773        /* Run callback if appropriate */
 774        if (slot->callback_func != NULL)
 775                slot->callback_func(slot->callback_data);
 776}
 777
 778void finish_all_active_slots(void)
 779{
 780        struct active_request_slot *slot = active_queue_head;
 781
 782        while (slot != NULL)
 783                if (slot->in_use) {
 784                        run_active_slot(slot);
 785                        slot = active_queue_head;
 786                } else {
 787                        slot = slot->next;
 788                }
 789}
 790
 791/* Helpers for modifying and creating URLs */
 792static inline int needs_quote(int ch)
 793{
 794        if (((ch >= 'A') && (ch <= 'Z'))
 795                        || ((ch >= 'a') && (ch <= 'z'))
 796                        || ((ch >= '0') && (ch <= '9'))
 797                        || (ch == '/')
 798                        || (ch == '-')
 799                        || (ch == '.'))
 800                return 0;
 801        return 1;
 802}
 803
 804static char *quote_ref_url(const char *base, const char *ref)
 805{
 806        struct strbuf buf = STRBUF_INIT;
 807        const char *cp;
 808        int ch;
 809
 810        end_url_with_slash(&buf, base);
 811
 812        for (cp = ref; (ch = *cp) != 0; cp++)
 813                if (needs_quote(ch))
 814                        strbuf_addf(&buf, "%%%02x", ch);
 815                else
 816                        strbuf_addch(&buf, *cp);
 817
 818        return strbuf_detach(&buf, NULL);
 819}
 820
 821void append_remote_object_url(struct strbuf *buf, const char *url,
 822                              const char *hex,
 823                              int only_two_digit_prefix)
 824{
 825        end_url_with_slash(buf, url);
 826
 827        strbuf_addf(buf, "objects/%.*s/", 2, hex);
 828        if (!only_two_digit_prefix)
 829                strbuf_addf(buf, "%s", hex+2);
 830}
 831
 832char *get_remote_object_url(const char *url, const char *hex,
 833                            int only_two_digit_prefix)
 834{
 835        struct strbuf buf = STRBUF_INIT;
 836        append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
 837        return strbuf_detach(&buf, NULL);
 838}
 839
 840int handle_curl_result(struct slot_results *results)
 841{
 842        /*
 843         * If we see a failing http code with CURLE_OK, we have turned off
 844         * FAILONERROR (to keep the server's custom error response), and should
 845         * translate the code into failure here.
 846         */
 847        if (results->curl_result == CURLE_OK &&
 848            results->http_code >= 400) {
 849                results->curl_result = CURLE_HTTP_RETURNED_ERROR;
 850                /*
 851                 * Normally curl will already have put the "reason phrase"
 852                 * from the server into curl_errorstr; unfortunately without
 853                 * FAILONERROR it is lost, so we can give only the numeric
 854                 * status code.
 855                 */
 856                snprintf(curl_errorstr, sizeof(curl_errorstr),
 857                         "The requested URL returned error: %ld",
 858                         results->http_code);
 859        }
 860
 861        if (results->curl_result == CURLE_OK) {
 862                credential_approve(&http_auth);
 863                return HTTP_OK;
 864        } else if (missing_target(results))
 865                return HTTP_MISSING_TARGET;
 866        else if (results->http_code == 401) {
 867                if (http_auth.username && http_auth.password) {
 868                        credential_reject(&http_auth);
 869                        return HTTP_NOAUTH;
 870                } else {
 871                        return HTTP_REAUTH;
 872                }
 873        } else {
 874#if LIBCURL_VERSION_NUM >= 0x070c00
 875                if (!curl_errorstr[0])
 876                        strlcpy(curl_errorstr,
 877                                curl_easy_strerror(results->curl_result),
 878                                sizeof(curl_errorstr));
 879#endif
 880                return HTTP_ERROR;
 881        }
 882}
 883
 884int run_one_slot(struct active_request_slot *slot,
 885                 struct slot_results *results)
 886{
 887        slot->results = results;
 888        if (!start_active_slot(slot)) {
 889                snprintf(curl_errorstr, sizeof(curl_errorstr),
 890                         "failed to start HTTP request");
 891                return HTTP_START_FAILED;
 892        }
 893
 894        run_active_slot(slot);
 895        return handle_curl_result(results);
 896}
 897
 898static CURLcode curlinfo_strbuf(CURL *curl, CURLINFO info, struct strbuf *buf)
 899{
 900        char *ptr;
 901        CURLcode ret;
 902
 903        strbuf_reset(buf);
 904        ret = curl_easy_getinfo(curl, info, &ptr);
 905        if (!ret && ptr)
 906                strbuf_addstr(buf, ptr);
 907        return ret;
 908}
 909
 910/*
 911 * Check for and extract a content-type parameter. "raw"
 912 * should be positioned at the start of the potential
 913 * parameter, with any whitespace already removed.
 914 *
 915 * "name" is the name of the parameter. The value is appended
 916 * to "out".
 917 */
 918static int extract_param(const char *raw, const char *name,
 919                         struct strbuf *out)
 920{
 921        size_t len = strlen(name);
 922
 923        if (strncasecmp(raw, name, len))
 924                return -1;
 925        raw += len;
 926
 927        if (*raw != '=')
 928                return -1;
 929        raw++;
 930
 931        while (*raw && !isspace(*raw) && *raw != ';')
 932                strbuf_addch(out, *raw++);
 933        return 0;
 934}
 935
 936/*
 937 * Extract a normalized version of the content type, with any
 938 * spaces suppressed, all letters lowercased, and no trailing ";"
 939 * or parameters.
 940 *
 941 * Note that we will silently remove even invalid whitespace. For
 942 * example, "text / plain" is specifically forbidden by RFC 2616,
 943 * but "text/plain" is the only reasonable output, and this keeps
 944 * our code simple.
 945 *
 946 * If the "charset" argument is not NULL, store the value of any
 947 * charset parameter there.
 948 *
 949 * Example:
 950 *   "TEXT/PLAIN; charset=utf-8" -> "text/plain", "utf-8"
 951 *   "text / plain" -> "text/plain"
 952 */
 953static void extract_content_type(struct strbuf *raw, struct strbuf *type,
 954                                 struct strbuf *charset)
 955{
 956        const char *p;
 957
 958        strbuf_reset(type);
 959        strbuf_grow(type, raw->len);
 960        for (p = raw->buf; *p; p++) {
 961                if (isspace(*p))
 962                        continue;
 963                if (*p == ';') {
 964                        p++;
 965                        break;
 966                }
 967                strbuf_addch(type, tolower(*p));
 968        }
 969
 970        if (!charset)
 971                return;
 972
 973        strbuf_reset(charset);
 974        while (*p) {
 975                while (isspace(*p) || *p == ';')
 976                        p++;
 977                if (!extract_param(p, "charset", charset))
 978                        return;
 979                while (*p && !isspace(*p))
 980                        p++;
 981        }
 982
 983        if (!charset->len && starts_with(type->buf, "text/"))
 984                strbuf_addstr(charset, "ISO-8859-1");
 985}
 986
 987/* http_request() targets */
 988#define HTTP_REQUEST_STRBUF     0
 989#define HTTP_REQUEST_FILE       1
 990
 991static int http_request(const char *url,
 992                        void *result, int target,
 993                        const struct http_get_options *options)
 994{
 995        struct active_request_slot *slot;
 996        struct slot_results results;
 997        struct curl_slist *headers = NULL;
 998        struct strbuf buf = STRBUF_INIT;
 999        int ret;
1000
1001        slot = get_active_slot();
1002        curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1003
1004        if (result == NULL) {
1005                curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
1006        } else {
1007                curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
1008                curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
1009
1010                if (target == HTTP_REQUEST_FILE) {
1011                        long posn = ftell(result);
1012                        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1013                                         fwrite);
1014                        if (posn > 0) {
1015                                strbuf_addf(&buf, "Range: bytes=%ld-", posn);
1016                                headers = curl_slist_append(headers, buf.buf);
1017                                strbuf_reset(&buf);
1018                        }
1019                } else
1020                        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1021                                         fwrite_buffer);
1022        }
1023
1024        strbuf_addstr(&buf, "Pragma:");
1025        if (options && options->no_cache)
1026                strbuf_addstr(&buf, " no-cache");
1027        if (options && options->keep_error)
1028                curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
1029
1030        headers = curl_slist_append(headers, buf.buf);
1031
1032        curl_easy_setopt(slot->curl, CURLOPT_URL, url);
1033        curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
1034        curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "gzip");
1035
1036        ret = run_one_slot(slot, &results);
1037
1038        if (options && options->content_type) {
1039                struct strbuf raw = STRBUF_INIT;
1040                curlinfo_strbuf(slot->curl, CURLINFO_CONTENT_TYPE, &raw);
1041                extract_content_type(&raw, options->content_type,
1042                                     options->charset);
1043                strbuf_release(&raw);
1044        }
1045
1046        if (options && options->effective_url)
1047                curlinfo_strbuf(slot->curl, CURLINFO_EFFECTIVE_URL,
1048                                options->effective_url);
1049
1050        curl_slist_free_all(headers);
1051        strbuf_release(&buf);
1052
1053        return ret;
1054}
1055
1056/*
1057 * Update the "base" url to a more appropriate value, as deduced by
1058 * redirects seen when requesting a URL starting with "url".
1059 *
1060 * The "asked" parameter is a URL that we asked curl to access, and must begin
1061 * with "base".
1062 *
1063 * The "got" parameter is the URL that curl reported to us as where we ended
1064 * up.
1065 *
1066 * Returns 1 if we updated the base url, 0 otherwise.
1067 *
1068 * Our basic strategy is to compare "base" and "asked" to find the bits
1069 * specific to our request. We then strip those bits off of "got" to yield the
1070 * new base. So for example, if our base is "http://example.com/foo.git",
1071 * and we ask for "http://example.com/foo.git/info/refs", we might end up
1072 * with "https://other.example.com/foo.git/info/refs". We would want the
1073 * new URL to become "https://other.example.com/foo.git".
1074 *
1075 * Note that this assumes a sane redirect scheme. It's entirely possible
1076 * in the example above to end up at a URL that does not even end in
1077 * "info/refs".  In such a case we simply punt, as there is not much we can
1078 * do (and such a scheme is unlikely to represent a real git repository,
1079 * which means we are likely about to abort anyway).
1080 */
1081static int update_url_from_redirect(struct strbuf *base,
1082                                    const char *asked,
1083                                    const struct strbuf *got)
1084{
1085        const char *tail;
1086        size_t tail_len;
1087
1088        if (!strcmp(asked, got->buf))
1089                return 0;
1090
1091        if (!skip_prefix(asked, base->buf, &tail))
1092                die("BUG: update_url_from_redirect: %s is not a superset of %s",
1093                    asked, base->buf);
1094
1095        tail_len = strlen(tail);
1096
1097        if (got->len < tail_len ||
1098            strcmp(tail, got->buf + got->len - tail_len))
1099                return 0; /* insane redirect scheme */
1100
1101        strbuf_reset(base);
1102        strbuf_add(base, got->buf, got->len - tail_len);
1103        return 1;
1104}
1105
1106static int http_request_reauth(const char *url,
1107                               void *result, int target,
1108                               struct http_get_options *options)
1109{
1110        int ret = http_request(url, result, target, options);
1111
1112        if (options && options->effective_url && options->base_url) {
1113                if (update_url_from_redirect(options->base_url,
1114                                             url, options->effective_url)) {
1115                        credential_from_url(&http_auth, options->base_url->buf);
1116                        url = options->effective_url->buf;
1117                }
1118        }
1119
1120        if (ret != HTTP_REAUTH)
1121                return ret;
1122
1123        /*
1124         * If we are using KEEP_ERROR, the previous request may have
1125         * put cruft into our output stream; we should clear it out before
1126         * making our next request. We only know how to do this for
1127         * the strbuf case, but that is enough to satisfy current callers.
1128         */
1129        if (options && options->keep_error) {
1130                switch (target) {
1131                case HTTP_REQUEST_STRBUF:
1132                        strbuf_reset(result);
1133                        break;
1134                default:
1135                        die("BUG: HTTP_KEEP_ERROR is only supported with strbufs");
1136                }
1137        }
1138
1139        credential_fill(&http_auth);
1140
1141        return http_request(url, result, target, options);
1142}
1143
1144int http_get_strbuf(const char *url,
1145                    struct strbuf *result,
1146                    struct http_get_options *options)
1147{
1148        return http_request_reauth(url, result, HTTP_REQUEST_STRBUF, options);
1149}
1150
1151/*
1152 * Downloads a URL and stores the result in the given file.
1153 *
1154 * If a previous interrupted download is detected (i.e. a previous temporary
1155 * file is still around) the download is resumed.
1156 */
1157static int http_get_file(const char *url, const char *filename,
1158                         struct http_get_options *options)
1159{
1160        int ret;
1161        struct strbuf tmpfile = STRBUF_INIT;
1162        FILE *result;
1163
1164        strbuf_addf(&tmpfile, "%s.temp", filename);
1165        result = fopen(tmpfile.buf, "a");
1166        if (!result) {
1167                error("Unable to open local file %s", tmpfile.buf);
1168                ret = HTTP_ERROR;
1169                goto cleanup;
1170        }
1171
1172        ret = http_request_reauth(url, result, HTTP_REQUEST_FILE, options);
1173        fclose(result);
1174
1175        if (ret == HTTP_OK && move_temp_to_file(tmpfile.buf, filename))
1176                ret = HTTP_ERROR;
1177cleanup:
1178        strbuf_release(&tmpfile);
1179        return ret;
1180}
1181
1182int http_fetch_ref(const char *base, struct ref *ref)
1183{
1184        struct http_get_options options = {0};
1185        char *url;
1186        struct strbuf buffer = STRBUF_INIT;
1187        int ret = -1;
1188
1189        options.no_cache = 1;
1190
1191        url = quote_ref_url(base, ref->name);
1192        if (http_get_strbuf(url, &buffer, &options) == HTTP_OK) {
1193                strbuf_rtrim(&buffer);
1194                if (buffer.len == 40)
1195                        ret = get_sha1_hex(buffer.buf, ref->old_sha1);
1196                else if (starts_with(buffer.buf, "ref: ")) {
1197                        ref->symref = xstrdup(buffer.buf + 5);
1198                        ret = 0;
1199                }
1200        }
1201
1202        strbuf_release(&buffer);
1203        free(url);
1204        return ret;
1205}
1206
1207/* Helpers for fetching packs */
1208static char *fetch_pack_index(unsigned char *sha1, const char *base_url)
1209{
1210        char *url, *tmp;
1211        struct strbuf buf = STRBUF_INIT;
1212
1213        if (http_is_verbose)
1214                fprintf(stderr, "Getting index for pack %s\n", sha1_to_hex(sha1));
1215
1216        end_url_with_slash(&buf, base_url);
1217        strbuf_addf(&buf, "objects/pack/pack-%s.idx", sha1_to_hex(sha1));
1218        url = strbuf_detach(&buf, NULL);
1219
1220        strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(sha1));
1221        tmp = strbuf_detach(&buf, NULL);
1222
1223        if (http_get_file(url, tmp, NULL) != HTTP_OK) {
1224                error("Unable to get pack index %s", url);
1225                free(tmp);
1226                tmp = NULL;
1227        }
1228
1229        free(url);
1230        return tmp;
1231}
1232
1233static int fetch_and_setup_pack_index(struct packed_git **packs_head,
1234        unsigned char *sha1, const char *base_url)
1235{
1236        struct packed_git *new_pack;
1237        char *tmp_idx = NULL;
1238        int ret;
1239
1240        if (has_pack_index(sha1)) {
1241                new_pack = parse_pack_index(sha1, NULL);
1242                if (!new_pack)
1243                        return -1; /* parse_pack_index() already issued error message */
1244                goto add_pack;
1245        }
1246
1247        tmp_idx = fetch_pack_index(sha1, base_url);
1248        if (!tmp_idx)
1249                return -1;
1250
1251        new_pack = parse_pack_index(sha1, tmp_idx);
1252        if (!new_pack) {
1253                unlink(tmp_idx);
1254                free(tmp_idx);
1255
1256                return -1; /* parse_pack_index() already issued error message */
1257        }
1258
1259        ret = verify_pack_index(new_pack);
1260        if (!ret) {
1261                close_pack_index(new_pack);
1262                ret = move_temp_to_file(tmp_idx, sha1_pack_index_name(sha1));
1263        }
1264        free(tmp_idx);
1265        if (ret)
1266                return -1;
1267
1268add_pack:
1269        new_pack->next = *packs_head;
1270        *packs_head = new_pack;
1271        return 0;
1272}
1273
1274int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
1275{
1276        struct http_get_options options = {0};
1277        int ret = 0, i = 0;
1278        char *url, *data;
1279        struct strbuf buf = STRBUF_INIT;
1280        unsigned char sha1[20];
1281
1282        end_url_with_slash(&buf, base_url);
1283        strbuf_addstr(&buf, "objects/info/packs");
1284        url = strbuf_detach(&buf, NULL);
1285
1286        options.no_cache = 1;
1287        ret = http_get_strbuf(url, &buf, &options);
1288        if (ret != HTTP_OK)
1289                goto cleanup;
1290
1291        data = buf.buf;
1292        while (i < buf.len) {
1293                switch (data[i]) {
1294                case 'P':
1295                        i++;
1296                        if (i + 52 <= buf.len &&
1297                            starts_with(data + i, " pack-") &&
1298                            starts_with(data + i + 46, ".pack\n")) {
1299                                get_sha1_hex(data + i + 6, sha1);
1300                                fetch_and_setup_pack_index(packs_head, sha1,
1301                                                      base_url);
1302                                i += 51;
1303                                break;
1304                        }
1305                default:
1306                        while (i < buf.len && data[i] != '\n')
1307                                i++;
1308                }
1309                i++;
1310        }
1311
1312cleanup:
1313        free(url);
1314        return ret;
1315}
1316
1317void release_http_pack_request(struct http_pack_request *preq)
1318{
1319        if (preq->packfile != NULL) {
1320                fclose(preq->packfile);
1321                preq->packfile = NULL;
1322        }
1323        if (preq->range_header != NULL) {
1324                curl_slist_free_all(preq->range_header);
1325                preq->range_header = NULL;
1326        }
1327        preq->slot = NULL;
1328        free(preq->url);
1329}
1330
1331int finish_http_pack_request(struct http_pack_request *preq)
1332{
1333        struct packed_git **lst;
1334        struct packed_git *p = preq->target;
1335        char *tmp_idx;
1336        struct child_process ip;
1337        const char *ip_argv[8];
1338
1339        close_pack_index(p);
1340
1341        fclose(preq->packfile);
1342        preq->packfile = NULL;
1343
1344        lst = preq->lst;
1345        while (*lst != p)
1346                lst = &((*lst)->next);
1347        *lst = (*lst)->next;
1348
1349        tmp_idx = xstrdup(preq->tmpfile);
1350        strcpy(tmp_idx + strlen(tmp_idx) - strlen(".pack.temp"),
1351               ".idx.temp");
1352
1353        ip_argv[0] = "index-pack";
1354        ip_argv[1] = "-o";
1355        ip_argv[2] = tmp_idx;
1356        ip_argv[3] = preq->tmpfile;
1357        ip_argv[4] = NULL;
1358
1359        memset(&ip, 0, sizeof(ip));
1360        ip.argv = ip_argv;
1361        ip.git_cmd = 1;
1362        ip.no_stdin = 1;
1363        ip.no_stdout = 1;
1364
1365        if (run_command(&ip)) {
1366                unlink(preq->tmpfile);
1367                unlink(tmp_idx);
1368                free(tmp_idx);
1369                return -1;
1370        }
1371
1372        unlink(sha1_pack_index_name(p->sha1));
1373
1374        if (move_temp_to_file(preq->tmpfile, sha1_pack_name(p->sha1))
1375         || move_temp_to_file(tmp_idx, sha1_pack_index_name(p->sha1))) {
1376                free(tmp_idx);
1377                return -1;
1378        }
1379
1380        install_packed_git(p);
1381        free(tmp_idx);
1382        return 0;
1383}
1384
1385struct http_pack_request *new_http_pack_request(
1386        struct packed_git *target, const char *base_url)
1387{
1388        long prev_posn = 0;
1389        char range[RANGE_HEADER_SIZE];
1390        struct strbuf buf = STRBUF_INIT;
1391        struct http_pack_request *preq;
1392
1393        preq = xcalloc(1, sizeof(*preq));
1394        preq->target = target;
1395
1396        end_url_with_slash(&buf, base_url);
1397        strbuf_addf(&buf, "objects/pack/pack-%s.pack",
1398                sha1_to_hex(target->sha1));
1399        preq->url = strbuf_detach(&buf, NULL);
1400
1401        snprintf(preq->tmpfile, sizeof(preq->tmpfile), "%s.temp",
1402                sha1_pack_name(target->sha1));
1403        preq->packfile = fopen(preq->tmpfile, "a");
1404        if (!preq->packfile) {
1405                error("Unable to open local file %s for pack",
1406                      preq->tmpfile);
1407                goto abort;
1408        }
1409
1410        preq->slot = get_active_slot();
1411        curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
1412        curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
1413        curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
1414        curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1415                no_pragma_header);
1416
1417        /*
1418         * If there is data present from a previous transfer attempt,
1419         * resume where it left off
1420         */
1421        prev_posn = ftell(preq->packfile);
1422        if (prev_posn>0) {
1423                if (http_is_verbose)
1424                        fprintf(stderr,
1425                                "Resuming fetch of pack %s at byte %ld\n",
1426                                sha1_to_hex(target->sha1), prev_posn);
1427                sprintf(range, "Range: bytes=%ld-", prev_posn);
1428                preq->range_header = curl_slist_append(NULL, range);
1429                curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1430                        preq->range_header);
1431        }
1432
1433        return preq;
1434
1435abort:
1436        free(preq->url);
1437        free(preq);
1438        return NULL;
1439}
1440
1441/* Helpers for fetching objects (loose) */
1442static size_t fwrite_sha1_file(char *ptr, size_t eltsize, size_t nmemb,
1443                               void *data)
1444{
1445        unsigned char expn[4096];
1446        size_t size = eltsize * nmemb;
1447        int posn = 0;
1448        struct http_object_request *freq =
1449                (struct http_object_request *)data;
1450        do {
1451                ssize_t retval = xwrite(freq->localfile,
1452                                        (char *) ptr + posn, size - posn);
1453                if (retval < 0)
1454                        return posn;
1455                posn += retval;
1456        } while (posn < size);
1457
1458        freq->stream.avail_in = size;
1459        freq->stream.next_in = (void *)ptr;
1460        do {
1461                freq->stream.next_out = expn;
1462                freq->stream.avail_out = sizeof(expn);
1463                freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
1464                git_SHA1_Update(&freq->c, expn,
1465                                sizeof(expn) - freq->stream.avail_out);
1466        } while (freq->stream.avail_in && freq->zret == Z_OK);
1467        return size;
1468}
1469
1470struct http_object_request *new_http_object_request(const char *base_url,
1471        unsigned char *sha1)
1472{
1473        char *hex = sha1_to_hex(sha1);
1474        const char *filename;
1475        char prevfile[PATH_MAX];
1476        int prevlocal;
1477        char prev_buf[PREV_BUF_SIZE];
1478        ssize_t prev_read = 0;
1479        long prev_posn = 0;
1480        char range[RANGE_HEADER_SIZE];
1481        struct curl_slist *range_header = NULL;
1482        struct http_object_request *freq;
1483
1484        freq = xcalloc(1, sizeof(*freq));
1485        hashcpy(freq->sha1, sha1);
1486        freq->localfile = -1;
1487
1488        filename = sha1_file_name(sha1);
1489        snprintf(freq->tmpfile, sizeof(freq->tmpfile),
1490                 "%s.temp", filename);
1491
1492        snprintf(prevfile, sizeof(prevfile), "%s.prev", filename);
1493        unlink_or_warn(prevfile);
1494        rename(freq->tmpfile, prevfile);
1495        unlink_or_warn(freq->tmpfile);
1496
1497        if (freq->localfile != -1)
1498                error("fd leakage in start: %d", freq->localfile);
1499        freq->localfile = open(freq->tmpfile,
1500                               O_WRONLY | O_CREAT | O_EXCL, 0666);
1501        /*
1502         * This could have failed due to the "lazy directory creation";
1503         * try to mkdir the last path component.
1504         */
1505        if (freq->localfile < 0 && errno == ENOENT) {
1506                char *dir = strrchr(freq->tmpfile, '/');
1507                if (dir) {
1508                        *dir = 0;
1509                        mkdir(freq->tmpfile, 0777);
1510                        *dir = '/';
1511                }
1512                freq->localfile = open(freq->tmpfile,
1513                                       O_WRONLY | O_CREAT | O_EXCL, 0666);
1514        }
1515
1516        if (freq->localfile < 0) {
1517                error("Couldn't create temporary file %s: %s",
1518                      freq->tmpfile, strerror(errno));
1519                goto abort;
1520        }
1521
1522        git_inflate_init(&freq->stream);
1523
1524        git_SHA1_Init(&freq->c);
1525
1526        freq->url = get_remote_object_url(base_url, hex, 0);
1527
1528        /*
1529         * If a previous temp file is present, process what was already
1530         * fetched.
1531         */
1532        prevlocal = open(prevfile, O_RDONLY);
1533        if (prevlocal != -1) {
1534                do {
1535                        prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
1536                        if (prev_read>0) {
1537                                if (fwrite_sha1_file(prev_buf,
1538                                                     1,
1539                                                     prev_read,
1540                                                     freq) == prev_read) {
1541                                        prev_posn += prev_read;
1542                                } else {
1543                                        prev_read = -1;
1544                                }
1545                        }
1546                } while (prev_read > 0);
1547                close(prevlocal);
1548        }
1549        unlink_or_warn(prevfile);
1550
1551        /*
1552         * Reset inflate/SHA1 if there was an error reading the previous temp
1553         * file; also rewind to the beginning of the local file.
1554         */
1555        if (prev_read == -1) {
1556                memset(&freq->stream, 0, sizeof(freq->stream));
1557                git_inflate_init(&freq->stream);
1558                git_SHA1_Init(&freq->c);
1559                if (prev_posn>0) {
1560                        prev_posn = 0;
1561                        lseek(freq->localfile, 0, SEEK_SET);
1562                        if (ftruncate(freq->localfile, 0) < 0) {
1563                                error("Couldn't truncate temporary file %s: %s",
1564                                          freq->tmpfile, strerror(errno));
1565                                goto abort;
1566                        }
1567                }
1568        }
1569
1570        freq->slot = get_active_slot();
1571
1572        curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
1573        curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
1574        curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
1575        curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
1576        curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
1577
1578        /*
1579         * If we have successfully processed data from a previous fetch
1580         * attempt, only fetch the data we don't already have.
1581         */
1582        if (prev_posn>0) {
1583                if (http_is_verbose)
1584                        fprintf(stderr,
1585                                "Resuming fetch of object %s at byte %ld\n",
1586                                hex, prev_posn);
1587                sprintf(range, "Range: bytes=%ld-", prev_posn);
1588                range_header = curl_slist_append(range_header, range);
1589                curl_easy_setopt(freq->slot->curl,
1590                                 CURLOPT_HTTPHEADER, range_header);
1591        }
1592
1593        return freq;
1594
1595abort:
1596        free(freq->url);
1597        free(freq);
1598        return NULL;
1599}
1600
1601void process_http_object_request(struct http_object_request *freq)
1602{
1603        if (freq->slot == NULL)
1604                return;
1605        freq->curl_result = freq->slot->curl_result;
1606        freq->http_code = freq->slot->http_code;
1607        freq->slot = NULL;
1608}
1609
1610int finish_http_object_request(struct http_object_request *freq)
1611{
1612        struct stat st;
1613
1614        close(freq->localfile);
1615        freq->localfile = -1;
1616
1617        process_http_object_request(freq);
1618
1619        if (freq->http_code == 416) {
1620                warning("requested range invalid; we may already have all the data.");
1621        } else if (freq->curl_result != CURLE_OK) {
1622                if (stat(freq->tmpfile, &st) == 0)
1623                        if (st.st_size == 0)
1624                                unlink_or_warn(freq->tmpfile);
1625                return -1;
1626        }
1627
1628        git_inflate_end(&freq->stream);
1629        git_SHA1_Final(freq->real_sha1, &freq->c);
1630        if (freq->zret != Z_STREAM_END) {
1631                unlink_or_warn(freq->tmpfile);
1632                return -1;
1633        }
1634        if (hashcmp(freq->sha1, freq->real_sha1)) {
1635                unlink_or_warn(freq->tmpfile);
1636                return -1;
1637        }
1638        freq->rename =
1639                move_temp_to_file(freq->tmpfile, sha1_file_name(freq->sha1));
1640
1641        return freq->rename;
1642}
1643
1644void abort_http_object_request(struct http_object_request *freq)
1645{
1646        unlink_or_warn(freq->tmpfile);
1647
1648        release_http_object_request(freq);
1649}
1650
1651void release_http_object_request(struct http_object_request *freq)
1652{
1653        if (freq->localfile != -1) {
1654                close(freq->localfile);
1655                freq->localfile = -1;
1656        }
1657        if (freq->url != NULL) {
1658                free(freq->url);
1659                freq->url = NULL;
1660        }
1661        if (freq->slot != NULL) {
1662                freq->slot->callback_func = NULL;
1663                freq->slot->callback_data = NULL;
1664                release_active_slot(freq->slot);
1665                freq->slot = NULL;
1666        }
1667}