http.con commit index-pack: fix compilation with NO_PTHREADS (e0e2128)
   1#include "http.h"
   2#include "pack.h"
   3#include "sideband.h"
   4#include "run-command.h"
   5#include "url.h"
   6#include "urlmatch.h"
   7#include "credential.h"
   8#include "version.h"
   9#include "pkt-line.h"
  10
  11int active_requests;
  12int http_is_verbose;
  13size_t http_post_buffer = 16 * LARGE_PACKET_MAX;
  14
  15#if LIBCURL_VERSION_NUM >= 0x070a06
  16#define LIBCURL_CAN_HANDLE_AUTH_ANY
  17#endif
  18
  19static int min_curl_sessions = 1;
  20static int curl_session_count;
  21#ifdef USE_CURL_MULTI
  22static int max_requests = -1;
  23static CURLM *curlm;
  24#endif
  25#ifndef NO_CURL_EASY_DUPHANDLE
  26static CURL *curl_default;
  27#endif
  28
  29#define PREV_BUF_SIZE 4096
  30#define RANGE_HEADER_SIZE 30
  31
  32char curl_errorstr[CURL_ERROR_SIZE];
  33
  34static int curl_ssl_verify = -1;
  35static int curl_ssl_try;
  36static const char *ssl_cert;
  37#if LIBCURL_VERSION_NUM >= 0x070903
  38static const char *ssl_key;
  39#endif
  40#if LIBCURL_VERSION_NUM >= 0x070908
  41static const char *ssl_capath;
  42#endif
  43static const char *ssl_cainfo;
  44static long curl_low_speed_limit = -1;
  45static long curl_low_speed_time = -1;
  46static int curl_ftp_no_epsv;
  47static const char *curl_http_proxy;
  48static const char *curl_cookie_file;
  49static int curl_save_cookies;
  50struct credential http_auth = CREDENTIAL_INIT;
  51static int http_proactive_auth;
  52static const char *user_agent;
  53
  54#if LIBCURL_VERSION_NUM >= 0x071700
  55/* Use CURLOPT_KEYPASSWD as is */
  56#elif LIBCURL_VERSION_NUM >= 0x070903
  57#define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
  58#else
  59#define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
  60#endif
  61
  62static struct credential cert_auth = CREDENTIAL_INIT;
  63static int ssl_cert_password_required;
  64
  65static struct curl_slist *pragma_header;
  66static struct curl_slist *no_pragma_header;
  67
  68static struct active_request_slot *active_queue_head;
  69
  70size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
  71{
  72        size_t size = eltsize * nmemb;
  73        struct buffer *buffer = buffer_;
  74
  75        if (size > buffer->buf.len - buffer->posn)
  76                size = buffer->buf.len - buffer->posn;
  77        memcpy(ptr, buffer->buf.buf + buffer->posn, size);
  78        buffer->posn += size;
  79
  80        return size;
  81}
  82
  83#ifndef NO_CURL_IOCTL
  84curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
  85{
  86        struct buffer *buffer = clientp;
  87
  88        switch (cmd) {
  89        case CURLIOCMD_NOP:
  90                return CURLIOE_OK;
  91
  92        case CURLIOCMD_RESTARTREAD:
  93                buffer->posn = 0;
  94                return CURLIOE_OK;
  95
  96        default:
  97                return CURLIOE_UNKNOWNCMD;
  98        }
  99}
 100#endif
 101
 102size_t fwrite_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
 103{
 104        size_t size = eltsize * nmemb;
 105        struct strbuf *buffer = buffer_;
 106
 107        strbuf_add(buffer, ptr, size);
 108        return size;
 109}
 110
 111size_t fwrite_null(char *ptr, size_t eltsize, size_t nmemb, void *strbuf)
 112{
 113        return eltsize * nmemb;
 114}
 115
 116#ifdef USE_CURL_MULTI
 117static void process_curl_messages(void)
 118{
 119        int num_messages;
 120        struct active_request_slot *slot;
 121        CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
 122
 123        while (curl_message != NULL) {
 124                if (curl_message->msg == CURLMSG_DONE) {
 125                        int curl_result = curl_message->data.result;
 126                        slot = active_queue_head;
 127                        while (slot != NULL &&
 128                               slot->curl != curl_message->easy_handle)
 129                                slot = slot->next;
 130                        if (slot != NULL) {
 131                                curl_multi_remove_handle(curlm, slot->curl);
 132                                slot->curl_result = curl_result;
 133                                finish_active_slot(slot);
 134                        } else {
 135                                fprintf(stderr, "Received DONE message for unknown request!\n");
 136                        }
 137                } else {
 138                        fprintf(stderr, "Unknown CURL message received: %d\n",
 139                                (int)curl_message->msg);
 140                }
 141                curl_message = curl_multi_info_read(curlm, &num_messages);
 142        }
 143}
 144#endif
 145
 146static int http_options(const char *var, const char *value, void *cb)
 147{
 148        if (!strcmp("http.sslverify", var)) {
 149                curl_ssl_verify = git_config_bool(var, value);
 150                return 0;
 151        }
 152        if (!strcmp("http.sslcert", var))
 153                return git_config_string(&ssl_cert, var, value);
 154#if LIBCURL_VERSION_NUM >= 0x070903
 155        if (!strcmp("http.sslkey", var))
 156                return git_config_string(&ssl_key, var, value);
 157#endif
 158#if LIBCURL_VERSION_NUM >= 0x070908
 159        if (!strcmp("http.sslcapath", var))
 160                return git_config_string(&ssl_capath, var, value);
 161#endif
 162        if (!strcmp("http.sslcainfo", var))
 163                return git_config_string(&ssl_cainfo, var, value);
 164        if (!strcmp("http.sslcertpasswordprotected", var)) {
 165                ssl_cert_password_required = git_config_bool(var, value);
 166                return 0;
 167        }
 168        if (!strcmp("http.ssltry", var)) {
 169                curl_ssl_try = git_config_bool(var, value);
 170                return 0;
 171        }
 172        if (!strcmp("http.minsessions", var)) {
 173                min_curl_sessions = git_config_int(var, value);
 174#ifndef USE_CURL_MULTI
 175                if (min_curl_sessions > 1)
 176                        min_curl_sessions = 1;
 177#endif
 178                return 0;
 179        }
 180#ifdef USE_CURL_MULTI
 181        if (!strcmp("http.maxrequests", var)) {
 182                max_requests = git_config_int(var, value);
 183                return 0;
 184        }
 185#endif
 186        if (!strcmp("http.lowspeedlimit", var)) {
 187                curl_low_speed_limit = (long)git_config_int(var, value);
 188                return 0;
 189        }
 190        if (!strcmp("http.lowspeedtime", var)) {
 191                curl_low_speed_time = (long)git_config_int(var, value);
 192                return 0;
 193        }
 194
 195        if (!strcmp("http.noepsv", var)) {
 196                curl_ftp_no_epsv = git_config_bool(var, value);
 197                return 0;
 198        }
 199        if (!strcmp("http.proxy", var))
 200                return git_config_string(&curl_http_proxy, var, value);
 201
 202        if (!strcmp("http.cookiefile", var))
 203                return git_config_string(&curl_cookie_file, var, value);
 204        if (!strcmp("http.savecookies", var)) {
 205                curl_save_cookies = git_config_bool(var, value);
 206                return 0;
 207        }
 208
 209        if (!strcmp("http.postbuffer", var)) {
 210                http_post_buffer = git_config_int(var, value);
 211                if (http_post_buffer < LARGE_PACKET_MAX)
 212                        http_post_buffer = LARGE_PACKET_MAX;
 213                return 0;
 214        }
 215
 216        if (!strcmp("http.useragent", var))
 217                return git_config_string(&user_agent, var, value);
 218
 219        /* Fall back on the default ones */
 220        return git_default_config(var, value, cb);
 221}
 222
 223static void init_curl_http_auth(CURL *result)
 224{
 225        if (!http_auth.username)
 226                return;
 227
 228        credential_fill(&http_auth);
 229
 230#if LIBCURL_VERSION_NUM >= 0x071301
 231        curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username);
 232        curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password);
 233#else
 234        {
 235                static struct strbuf up = STRBUF_INIT;
 236                /*
 237                 * Note that we assume we only ever have a single set of
 238                 * credentials in a given program run, so we do not have
 239                 * to worry about updating this buffer, only setting its
 240                 * initial value.
 241                 */
 242                if (!up.len)
 243                        strbuf_addf(&up, "%s:%s",
 244                                http_auth.username, http_auth.password);
 245                curl_easy_setopt(result, CURLOPT_USERPWD, up.buf);
 246        }
 247#endif
 248}
 249
 250static int has_cert_password(void)
 251{
 252        if (ssl_cert == NULL || ssl_cert_password_required != 1)
 253                return 0;
 254        if (!cert_auth.password) {
 255                cert_auth.protocol = xstrdup("cert");
 256                cert_auth.username = xstrdup("");
 257                cert_auth.path = xstrdup(ssl_cert);
 258                credential_fill(&cert_auth);
 259        }
 260        return 1;
 261}
 262
 263#if LIBCURL_VERSION_NUM >= 0x071900
 264static void set_curl_keepalive(CURL *c)
 265{
 266        curl_easy_setopt(c, CURLOPT_TCP_KEEPALIVE, 1);
 267}
 268
 269#elif LIBCURL_VERSION_NUM >= 0x071000
 270static int sockopt_callback(void *client, curl_socket_t fd, curlsocktype type)
 271{
 272        int ka = 1;
 273        int rc;
 274        socklen_t len = (socklen_t)sizeof(ka);
 275
 276        if (type != CURLSOCKTYPE_IPCXN)
 277                return 0;
 278
 279        rc = setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&ka, len);
 280        if (rc < 0)
 281                warning("unable to set SO_KEEPALIVE on socket %s",
 282                        strerror(errno));
 283
 284        return 0; /* CURL_SOCKOPT_OK only exists since curl 7.21.5 */
 285}
 286
 287static void set_curl_keepalive(CURL *c)
 288{
 289        curl_easy_setopt(c, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
 290}
 291
 292#else
 293static void set_curl_keepalive(CURL *c)
 294{
 295        /* not supported on older curl versions */
 296}
 297#endif
 298
 299static CURL *get_curl_handle(void)
 300{
 301        CURL *result = curl_easy_init();
 302
 303        if (!result)
 304                die("curl_easy_init failed");
 305
 306        if (!curl_ssl_verify) {
 307                curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
 308                curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
 309        } else {
 310                /* Verify authenticity of the peer's certificate */
 311                curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
 312                /* The name in the cert must match whom we tried to connect */
 313                curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
 314        }
 315
 316#if LIBCURL_VERSION_NUM >= 0x070907
 317        curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
 318#endif
 319#ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 320        curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 321#endif
 322
 323        if (http_proactive_auth)
 324                init_curl_http_auth(result);
 325
 326        if (ssl_cert != NULL)
 327                curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
 328        if (has_cert_password())
 329                curl_easy_setopt(result, CURLOPT_KEYPASSWD, cert_auth.password);
 330#if LIBCURL_VERSION_NUM >= 0x070903
 331        if (ssl_key != NULL)
 332                curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
 333#endif
 334#if LIBCURL_VERSION_NUM >= 0x070908
 335        if (ssl_capath != NULL)
 336                curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
 337#endif
 338        if (ssl_cainfo != NULL)
 339                curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
 340
 341        if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
 342                curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
 343                                 curl_low_speed_limit);
 344                curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
 345                                 curl_low_speed_time);
 346        }
 347
 348        curl_easy_setopt(result, CURLOPT_FOLLOWLOCATION, 1);
 349#if LIBCURL_VERSION_NUM >= 0x071301
 350        curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
 351#elif LIBCURL_VERSION_NUM >= 0x071101
 352        curl_easy_setopt(result, CURLOPT_POST301, 1);
 353#endif
 354
 355        if (getenv("GIT_CURL_VERBOSE"))
 356                curl_easy_setopt(result, CURLOPT_VERBOSE, 1);
 357
 358        curl_easy_setopt(result, CURLOPT_USERAGENT,
 359                user_agent ? user_agent : git_user_agent());
 360
 361        if (curl_ftp_no_epsv)
 362                curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
 363
 364#ifdef CURLOPT_USE_SSL
 365        if (curl_ssl_try)
 366                curl_easy_setopt(result, CURLOPT_USE_SSL, CURLUSESSL_TRY);
 367#endif
 368
 369        if (curl_http_proxy) {
 370                curl_easy_setopt(result, CURLOPT_PROXY, curl_http_proxy);
 371                curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 372        }
 373
 374        set_curl_keepalive(result);
 375
 376        return result;
 377}
 378
 379static void set_from_env(const char **var, const char *envname)
 380{
 381        const char *val = getenv(envname);
 382        if (val)
 383                *var = val;
 384}
 385
 386void http_init(struct remote *remote, const char *url, int proactive_auth)
 387{
 388        char *low_speed_limit;
 389        char *low_speed_time;
 390        char *normalized_url;
 391        struct urlmatch_config config = { STRING_LIST_INIT_DUP };
 392
 393        config.section = "http";
 394        config.key = NULL;
 395        config.collect_fn = http_options;
 396        config.cascade_fn = git_default_config;
 397        config.cb = NULL;
 398
 399        http_is_verbose = 0;
 400        normalized_url = url_normalize(url, &config.url);
 401
 402        git_config(urlmatch_config_entry, &config);
 403        free(normalized_url);
 404
 405        if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK)
 406                die("curl_global_init failed");
 407
 408        http_proactive_auth = proactive_auth;
 409
 410        if (remote && remote->http_proxy)
 411                curl_http_proxy = xstrdup(remote->http_proxy);
 412
 413        pragma_header = curl_slist_append(pragma_header, "Pragma: no-cache");
 414        no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
 415
 416#ifdef USE_CURL_MULTI
 417        {
 418                char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
 419                if (http_max_requests != NULL)
 420                        max_requests = atoi(http_max_requests);
 421        }
 422
 423        curlm = curl_multi_init();
 424        if (!curlm)
 425                die("curl_multi_init failed");
 426#endif
 427
 428        if (getenv("GIT_SSL_NO_VERIFY"))
 429                curl_ssl_verify = 0;
 430
 431        set_from_env(&ssl_cert, "GIT_SSL_CERT");
 432#if LIBCURL_VERSION_NUM >= 0x070903
 433        set_from_env(&ssl_key, "GIT_SSL_KEY");
 434#endif
 435#if LIBCURL_VERSION_NUM >= 0x070908
 436        set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
 437#endif
 438        set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
 439
 440        set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
 441
 442        low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
 443        if (low_speed_limit != NULL)
 444                curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
 445        low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
 446        if (low_speed_time != NULL)
 447                curl_low_speed_time = strtol(low_speed_time, NULL, 10);
 448
 449        if (curl_ssl_verify == -1)
 450                curl_ssl_verify = 1;
 451
 452        curl_session_count = 0;
 453#ifdef USE_CURL_MULTI
 454        if (max_requests < 1)
 455                max_requests = DEFAULT_MAX_REQUESTS;
 456#endif
 457
 458        if (getenv("GIT_CURL_FTP_NO_EPSV"))
 459                curl_ftp_no_epsv = 1;
 460
 461        if (url) {
 462                credential_from_url(&http_auth, url);
 463                if (!ssl_cert_password_required &&
 464                    getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
 465                    starts_with(url, "https://"))
 466                        ssl_cert_password_required = 1;
 467        }
 468
 469#ifndef NO_CURL_EASY_DUPHANDLE
 470        curl_default = get_curl_handle();
 471#endif
 472}
 473
 474void http_cleanup(void)
 475{
 476        struct active_request_slot *slot = active_queue_head;
 477
 478        while (slot != NULL) {
 479                struct active_request_slot *next = slot->next;
 480                if (slot->curl != NULL) {
 481#ifdef USE_CURL_MULTI
 482                        curl_multi_remove_handle(curlm, slot->curl);
 483#endif
 484                        curl_easy_cleanup(slot->curl);
 485                }
 486                free(slot);
 487                slot = next;
 488        }
 489        active_queue_head = NULL;
 490
 491#ifndef NO_CURL_EASY_DUPHANDLE
 492        curl_easy_cleanup(curl_default);
 493#endif
 494
 495#ifdef USE_CURL_MULTI
 496        curl_multi_cleanup(curlm);
 497#endif
 498        curl_global_cleanup();
 499
 500        curl_slist_free_all(pragma_header);
 501        pragma_header = NULL;
 502
 503        curl_slist_free_all(no_pragma_header);
 504        no_pragma_header = NULL;
 505
 506        if (curl_http_proxy) {
 507                free((void *)curl_http_proxy);
 508                curl_http_proxy = NULL;
 509        }
 510
 511        if (cert_auth.password != NULL) {
 512                memset(cert_auth.password, 0, strlen(cert_auth.password));
 513                free(cert_auth.password);
 514                cert_auth.password = NULL;
 515        }
 516        ssl_cert_password_required = 0;
 517}
 518
 519struct active_request_slot *get_active_slot(void)
 520{
 521        struct active_request_slot *slot = active_queue_head;
 522        struct active_request_slot *newslot;
 523
 524#ifdef USE_CURL_MULTI
 525        int num_transfers;
 526
 527        /* Wait for a slot to open up if the queue is full */
 528        while (active_requests >= max_requests) {
 529                curl_multi_perform(curlm, &num_transfers);
 530                if (num_transfers < active_requests)
 531                        process_curl_messages();
 532        }
 533#endif
 534
 535        while (slot != NULL && slot->in_use)
 536                slot = slot->next;
 537
 538        if (slot == NULL) {
 539                newslot = xmalloc(sizeof(*newslot));
 540                newslot->curl = NULL;
 541                newslot->in_use = 0;
 542                newslot->next = NULL;
 543
 544                slot = active_queue_head;
 545                if (slot == NULL) {
 546                        active_queue_head = newslot;
 547                } else {
 548                        while (slot->next != NULL)
 549                                slot = slot->next;
 550                        slot->next = newslot;
 551                }
 552                slot = newslot;
 553        }
 554
 555        if (slot->curl == NULL) {
 556#ifdef NO_CURL_EASY_DUPHANDLE
 557                slot->curl = get_curl_handle();
 558#else
 559                slot->curl = curl_easy_duphandle(curl_default);
 560#endif
 561                curl_session_count++;
 562        }
 563
 564        active_requests++;
 565        slot->in_use = 1;
 566        slot->results = NULL;
 567        slot->finished = NULL;
 568        slot->callback_data = NULL;
 569        slot->callback_func = NULL;
 570        curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
 571        if (curl_save_cookies)
 572                curl_easy_setopt(slot->curl, CURLOPT_COOKIEJAR, curl_cookie_file);
 573        curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
 574        curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
 575        curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
 576        curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
 577        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
 578        curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
 579        curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
 580        curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 581        curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 1);
 582        if (http_auth.password)
 583                init_curl_http_auth(slot->curl);
 584
 585        return slot;
 586}
 587
 588int start_active_slot(struct active_request_slot *slot)
 589{
 590#ifdef USE_CURL_MULTI
 591        CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
 592        int num_transfers;
 593
 594        if (curlm_result != CURLM_OK &&
 595            curlm_result != CURLM_CALL_MULTI_PERFORM) {
 596                active_requests--;
 597                slot->in_use = 0;
 598                return 0;
 599        }
 600
 601        /*
 602         * We know there must be something to do, since we just added
 603         * something.
 604         */
 605        curl_multi_perform(curlm, &num_transfers);
 606#endif
 607        return 1;
 608}
 609
 610#ifdef USE_CURL_MULTI
 611struct fill_chain {
 612        void *data;
 613        int (*fill)(void *);
 614        struct fill_chain *next;
 615};
 616
 617static struct fill_chain *fill_cfg;
 618
 619void add_fill_function(void *data, int (*fill)(void *))
 620{
 621        struct fill_chain *new = xmalloc(sizeof(*new));
 622        struct fill_chain **linkp = &fill_cfg;
 623        new->data = data;
 624        new->fill = fill;
 625        new->next = NULL;
 626        while (*linkp)
 627                linkp = &(*linkp)->next;
 628        *linkp = new;
 629}
 630
 631void fill_active_slots(void)
 632{
 633        struct active_request_slot *slot = active_queue_head;
 634
 635        while (active_requests < max_requests) {
 636                struct fill_chain *fill;
 637                for (fill = fill_cfg; fill; fill = fill->next)
 638                        if (fill->fill(fill->data))
 639                                break;
 640
 641                if (!fill)
 642                        break;
 643        }
 644
 645        while (slot != NULL) {
 646                if (!slot->in_use && slot->curl != NULL
 647                        && curl_session_count > min_curl_sessions) {
 648                        curl_easy_cleanup(slot->curl);
 649                        slot->curl = NULL;
 650                        curl_session_count--;
 651                }
 652                slot = slot->next;
 653        }
 654}
 655
 656void step_active_slots(void)
 657{
 658        int num_transfers;
 659        CURLMcode curlm_result;
 660
 661        do {
 662                curlm_result = curl_multi_perform(curlm, &num_transfers);
 663        } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
 664        if (num_transfers < active_requests) {
 665                process_curl_messages();
 666                fill_active_slots();
 667        }
 668}
 669#endif
 670
 671void run_active_slot(struct active_request_slot *slot)
 672{
 673#ifdef USE_CURL_MULTI
 674        fd_set readfds;
 675        fd_set writefds;
 676        fd_set excfds;
 677        int max_fd;
 678        struct timeval select_timeout;
 679        int finished = 0;
 680
 681        slot->finished = &finished;
 682        while (!finished) {
 683                step_active_slots();
 684
 685                if (slot->in_use) {
 686#if LIBCURL_VERSION_NUM >= 0x070f04
 687                        long curl_timeout;
 688                        curl_multi_timeout(curlm, &curl_timeout);
 689                        if (curl_timeout == 0) {
 690                                continue;
 691                        } else if (curl_timeout == -1) {
 692                                select_timeout.tv_sec  = 0;
 693                                select_timeout.tv_usec = 50000;
 694                        } else {
 695                                select_timeout.tv_sec  =  curl_timeout / 1000;
 696                                select_timeout.tv_usec = (curl_timeout % 1000) * 1000;
 697                        }
 698#else
 699                        select_timeout.tv_sec  = 0;
 700                        select_timeout.tv_usec = 50000;
 701#endif
 702
 703                        max_fd = -1;
 704                        FD_ZERO(&readfds);
 705                        FD_ZERO(&writefds);
 706                        FD_ZERO(&excfds);
 707                        curl_multi_fdset(curlm, &readfds, &writefds, &excfds, &max_fd);
 708
 709                        /*
 710                         * It can happen that curl_multi_timeout returns a pathologically
 711                         * long timeout when curl_multi_fdset returns no file descriptors
 712                         * to read.  See commit message for more details.
 713                         */
 714                        if (max_fd < 0 &&
 715                            (select_timeout.tv_sec > 0 ||
 716                             select_timeout.tv_usec > 50000)) {
 717                                select_timeout.tv_sec  = 0;
 718                                select_timeout.tv_usec = 50000;
 719                        }
 720
 721                        select(max_fd+1, &readfds, &writefds, &excfds, &select_timeout);
 722                }
 723        }
 724#else
 725        while (slot->in_use) {
 726                slot->curl_result = curl_easy_perform(slot->curl);
 727                finish_active_slot(slot);
 728        }
 729#endif
 730}
 731
 732static void closedown_active_slot(struct active_request_slot *slot)
 733{
 734        active_requests--;
 735        slot->in_use = 0;
 736}
 737
 738static void release_active_slot(struct active_request_slot *slot)
 739{
 740        closedown_active_slot(slot);
 741        if (slot->curl && curl_session_count > min_curl_sessions) {
 742#ifdef USE_CURL_MULTI
 743                curl_multi_remove_handle(curlm, slot->curl);
 744#endif
 745                curl_easy_cleanup(slot->curl);
 746                slot->curl = NULL;
 747                curl_session_count--;
 748        }
 749#ifdef USE_CURL_MULTI
 750        fill_active_slots();
 751#endif
 752}
 753
 754void finish_active_slot(struct active_request_slot *slot)
 755{
 756        closedown_active_slot(slot);
 757        curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
 758
 759        if (slot->finished != NULL)
 760                (*slot->finished) = 1;
 761
 762        /* Store slot results so they can be read after the slot is reused */
 763        if (slot->results != NULL) {
 764                slot->results->curl_result = slot->curl_result;
 765                slot->results->http_code = slot->http_code;
 766#if LIBCURL_VERSION_NUM >= 0x070a08
 767                curl_easy_getinfo(slot->curl, CURLINFO_HTTPAUTH_AVAIL,
 768                                  &slot->results->auth_avail);
 769#else
 770                slot->results->auth_avail = 0;
 771#endif
 772        }
 773
 774        /* Run callback if appropriate */
 775        if (slot->callback_func != NULL)
 776                slot->callback_func(slot->callback_data);
 777}
 778
 779void finish_all_active_slots(void)
 780{
 781        struct active_request_slot *slot = active_queue_head;
 782
 783        while (slot != NULL)
 784                if (slot->in_use) {
 785                        run_active_slot(slot);
 786                        slot = active_queue_head;
 787                } else {
 788                        slot = slot->next;
 789                }
 790}
 791
 792/* Helpers for modifying and creating URLs */
 793static inline int needs_quote(int ch)
 794{
 795        if (((ch >= 'A') && (ch <= 'Z'))
 796                        || ((ch >= 'a') && (ch <= 'z'))
 797                        || ((ch >= '0') && (ch <= '9'))
 798                        || (ch == '/')
 799                        || (ch == '-')
 800                        || (ch == '.'))
 801                return 0;
 802        return 1;
 803}
 804
 805static char *quote_ref_url(const char *base, const char *ref)
 806{
 807        struct strbuf buf = STRBUF_INIT;
 808        const char *cp;
 809        int ch;
 810
 811        end_url_with_slash(&buf, base);
 812
 813        for (cp = ref; (ch = *cp) != 0; cp++)
 814                if (needs_quote(ch))
 815                        strbuf_addf(&buf, "%%%02x", ch);
 816                else
 817                        strbuf_addch(&buf, *cp);
 818
 819        return strbuf_detach(&buf, NULL);
 820}
 821
 822void append_remote_object_url(struct strbuf *buf, const char *url,
 823                              const char *hex,
 824                              int only_two_digit_prefix)
 825{
 826        end_url_with_slash(buf, url);
 827
 828        strbuf_addf(buf, "objects/%.*s/", 2, hex);
 829        if (!only_two_digit_prefix)
 830                strbuf_addf(buf, "%s", hex+2);
 831}
 832
 833char *get_remote_object_url(const char *url, const char *hex,
 834                            int only_two_digit_prefix)
 835{
 836        struct strbuf buf = STRBUF_INIT;
 837        append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
 838        return strbuf_detach(&buf, NULL);
 839}
 840
 841int handle_curl_result(struct slot_results *results)
 842{
 843        /*
 844         * If we see a failing http code with CURLE_OK, we have turned off
 845         * FAILONERROR (to keep the server's custom error response), and should
 846         * translate the code into failure here.
 847         */
 848        if (results->curl_result == CURLE_OK &&
 849            results->http_code >= 400) {
 850                results->curl_result = CURLE_HTTP_RETURNED_ERROR;
 851                /*
 852                 * Normally curl will already have put the "reason phrase"
 853                 * from the server into curl_errorstr; unfortunately without
 854                 * FAILONERROR it is lost, so we can give only the numeric
 855                 * status code.
 856                 */
 857                snprintf(curl_errorstr, sizeof(curl_errorstr),
 858                         "The requested URL returned error: %ld",
 859                         results->http_code);
 860        }
 861
 862        if (results->curl_result == CURLE_OK) {
 863                credential_approve(&http_auth);
 864                return HTTP_OK;
 865        } else if (missing_target(results))
 866                return HTTP_MISSING_TARGET;
 867        else if (results->http_code == 401) {
 868                if (http_auth.username && http_auth.password) {
 869                        credential_reject(&http_auth);
 870                        return HTTP_NOAUTH;
 871                } else {
 872                        return HTTP_REAUTH;
 873                }
 874        } else {
 875#if LIBCURL_VERSION_NUM >= 0x070c00
 876                if (!curl_errorstr[0])
 877                        strlcpy(curl_errorstr,
 878                                curl_easy_strerror(results->curl_result),
 879                                sizeof(curl_errorstr));
 880#endif
 881                return HTTP_ERROR;
 882        }
 883}
 884
 885int run_one_slot(struct active_request_slot *slot,
 886                 struct slot_results *results)
 887{
 888        slot->results = results;
 889        if (!start_active_slot(slot)) {
 890                snprintf(curl_errorstr, sizeof(curl_errorstr),
 891                         "failed to start HTTP request");
 892                return HTTP_START_FAILED;
 893        }
 894
 895        run_active_slot(slot);
 896        return handle_curl_result(results);
 897}
 898
 899static CURLcode curlinfo_strbuf(CURL *curl, CURLINFO info, struct strbuf *buf)
 900{
 901        char *ptr;
 902        CURLcode ret;
 903
 904        strbuf_reset(buf);
 905        ret = curl_easy_getinfo(curl, info, &ptr);
 906        if (!ret && ptr)
 907                strbuf_addstr(buf, ptr);
 908        return ret;
 909}
 910
 911/*
 912 * Check for and extract a content-type parameter. "raw"
 913 * should be positioned at the start of the potential
 914 * parameter, with any whitespace already removed.
 915 *
 916 * "name" is the name of the parameter. The value is appended
 917 * to "out".
 918 */
 919static int extract_param(const char *raw, const char *name,
 920                         struct strbuf *out)
 921{
 922        size_t len = strlen(name);
 923
 924        if (strncasecmp(raw, name, len))
 925                return -1;
 926        raw += len;
 927
 928        if (*raw != '=')
 929                return -1;
 930        raw++;
 931
 932        while (*raw && !isspace(*raw) && *raw != ';')
 933                strbuf_addch(out, *raw++);
 934        return 0;
 935}
 936
 937/*
 938 * Extract a normalized version of the content type, with any
 939 * spaces suppressed, all letters lowercased, and no trailing ";"
 940 * or parameters.
 941 *
 942 * Note that we will silently remove even invalid whitespace. For
 943 * example, "text / plain" is specifically forbidden by RFC 2616,
 944 * but "text/plain" is the only reasonable output, and this keeps
 945 * our code simple.
 946 *
 947 * If the "charset" argument is not NULL, store the value of any
 948 * charset parameter there.
 949 *
 950 * Example:
 951 *   "TEXT/PLAIN; charset=utf-8" -> "text/plain", "utf-8"
 952 *   "text / plain" -> "text/plain"
 953 */
 954static void extract_content_type(struct strbuf *raw, struct strbuf *type,
 955                                 struct strbuf *charset)
 956{
 957        const char *p;
 958
 959        strbuf_reset(type);
 960        strbuf_grow(type, raw->len);
 961        for (p = raw->buf; *p; p++) {
 962                if (isspace(*p))
 963                        continue;
 964                if (*p == ';') {
 965                        p++;
 966                        break;
 967                }
 968                strbuf_addch(type, tolower(*p));
 969        }
 970
 971        if (!charset)
 972                return;
 973
 974        strbuf_reset(charset);
 975        while (*p) {
 976                while (isspace(*p) || *p == ';')
 977                        p++;
 978                if (!extract_param(p, "charset", charset))
 979                        return;
 980                while (*p && !isspace(*p))
 981                        p++;
 982        }
 983
 984        if (!charset->len && starts_with(type->buf, "text/"))
 985                strbuf_addstr(charset, "ISO-8859-1");
 986}
 987
 988/* http_request() targets */
 989#define HTTP_REQUEST_STRBUF     0
 990#define HTTP_REQUEST_FILE       1
 991
 992static int http_request(const char *url,
 993                        void *result, int target,
 994                        const struct http_get_options *options)
 995{
 996        struct active_request_slot *slot;
 997        struct slot_results results;
 998        struct curl_slist *headers = NULL;
 999        struct strbuf buf = STRBUF_INIT;
1000        int ret;
1001
1002        slot = get_active_slot();
1003        curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1004
1005        if (result == NULL) {
1006                curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
1007        } else {
1008                curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
1009                curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
1010
1011                if (target == HTTP_REQUEST_FILE) {
1012                        long posn = ftell(result);
1013                        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1014                                         fwrite);
1015                        if (posn > 0) {
1016                                strbuf_addf(&buf, "Range: bytes=%ld-", posn);
1017                                headers = curl_slist_append(headers, buf.buf);
1018                                strbuf_reset(&buf);
1019                        }
1020                } else
1021                        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1022                                         fwrite_buffer);
1023        }
1024
1025        strbuf_addstr(&buf, "Pragma:");
1026        if (options && options->no_cache)
1027                strbuf_addstr(&buf, " no-cache");
1028        if (options && options->keep_error)
1029                curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
1030
1031        headers = curl_slist_append(headers, buf.buf);
1032
1033        curl_easy_setopt(slot->curl, CURLOPT_URL, url);
1034        curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
1035        curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "gzip");
1036
1037        ret = run_one_slot(slot, &results);
1038
1039        if (options && options->content_type) {
1040                struct strbuf raw = STRBUF_INIT;
1041                curlinfo_strbuf(slot->curl, CURLINFO_CONTENT_TYPE, &raw);
1042                extract_content_type(&raw, options->content_type,
1043                                     options->charset);
1044                strbuf_release(&raw);
1045        }
1046
1047        if (options && options->effective_url)
1048                curlinfo_strbuf(slot->curl, CURLINFO_EFFECTIVE_URL,
1049                                options->effective_url);
1050
1051        curl_slist_free_all(headers);
1052        strbuf_release(&buf);
1053
1054        return ret;
1055}
1056
1057/*
1058 * Update the "base" url to a more appropriate value, as deduced by
1059 * redirects seen when requesting a URL starting with "url".
1060 *
1061 * The "asked" parameter is a URL that we asked curl to access, and must begin
1062 * with "base".
1063 *
1064 * The "got" parameter is the URL that curl reported to us as where we ended
1065 * up.
1066 *
1067 * Returns 1 if we updated the base url, 0 otherwise.
1068 *
1069 * Our basic strategy is to compare "base" and "asked" to find the bits
1070 * specific to our request. We then strip those bits off of "got" to yield the
1071 * new base. So for example, if our base is "http://example.com/foo.git",
1072 * and we ask for "http://example.com/foo.git/info/refs", we might end up
1073 * with "https://other.example.com/foo.git/info/refs". We would want the
1074 * new URL to become "https://other.example.com/foo.git".
1075 *
1076 * Note that this assumes a sane redirect scheme. It's entirely possible
1077 * in the example above to end up at a URL that does not even end in
1078 * "info/refs".  In such a case we simply punt, as there is not much we can
1079 * do (and such a scheme is unlikely to represent a real git repository,
1080 * which means we are likely about to abort anyway).
1081 */
1082static int update_url_from_redirect(struct strbuf *base,
1083                                    const char *asked,
1084                                    const struct strbuf *got)
1085{
1086        const char *tail;
1087        size_t tail_len;
1088
1089        if (!strcmp(asked, got->buf))
1090                return 0;
1091
1092        if (!skip_prefix(asked, base->buf, &tail))
1093                die("BUG: update_url_from_redirect: %s is not a superset of %s",
1094                    asked, base->buf);
1095
1096        tail_len = strlen(tail);
1097
1098        if (got->len < tail_len ||
1099            strcmp(tail, got->buf + got->len - tail_len))
1100                return 0; /* insane redirect scheme */
1101
1102        strbuf_reset(base);
1103        strbuf_add(base, got->buf, got->len - tail_len);
1104        return 1;
1105}
1106
1107static int http_request_reauth(const char *url,
1108                               void *result, int target,
1109                               struct http_get_options *options)
1110{
1111        int ret = http_request(url, result, target, options);
1112
1113        if (options && options->effective_url && options->base_url) {
1114                if (update_url_from_redirect(options->base_url,
1115                                             url, options->effective_url)) {
1116                        credential_from_url(&http_auth, options->base_url->buf);
1117                        url = options->effective_url->buf;
1118                }
1119        }
1120
1121        if (ret != HTTP_REAUTH)
1122                return ret;
1123
1124        /*
1125         * If we are using KEEP_ERROR, the previous request may have
1126         * put cruft into our output stream; we should clear it out before
1127         * making our next request. We only know how to do this for
1128         * the strbuf case, but that is enough to satisfy current callers.
1129         */
1130        if (options && options->keep_error) {
1131                switch (target) {
1132                case HTTP_REQUEST_STRBUF:
1133                        strbuf_reset(result);
1134                        break;
1135                default:
1136                        die("BUG: HTTP_KEEP_ERROR is only supported with strbufs");
1137                }
1138        }
1139
1140        credential_fill(&http_auth);
1141
1142        return http_request(url, result, target, options);
1143}
1144
1145int http_get_strbuf(const char *url,
1146                    struct strbuf *result,
1147                    struct http_get_options *options)
1148{
1149        return http_request_reauth(url, result, HTTP_REQUEST_STRBUF, options);
1150}
1151
1152/*
1153 * Downloads a URL and stores the result in the given file.
1154 *
1155 * If a previous interrupted download is detected (i.e. a previous temporary
1156 * file is still around) the download is resumed.
1157 */
1158static int http_get_file(const char *url, const char *filename,
1159                         struct http_get_options *options)
1160{
1161        int ret;
1162        struct strbuf tmpfile = STRBUF_INIT;
1163        FILE *result;
1164
1165        strbuf_addf(&tmpfile, "%s.temp", filename);
1166        result = fopen(tmpfile.buf, "a");
1167        if (!result) {
1168                error("Unable to open local file %s", tmpfile.buf);
1169                ret = HTTP_ERROR;
1170                goto cleanup;
1171        }
1172
1173        ret = http_request_reauth(url, result, HTTP_REQUEST_FILE, options);
1174        fclose(result);
1175
1176        if (ret == HTTP_OK && move_temp_to_file(tmpfile.buf, filename))
1177                ret = HTTP_ERROR;
1178cleanup:
1179        strbuf_release(&tmpfile);
1180        return ret;
1181}
1182
1183int http_fetch_ref(const char *base, struct ref *ref)
1184{
1185        struct http_get_options options = {0};
1186        char *url;
1187        struct strbuf buffer = STRBUF_INIT;
1188        int ret = -1;
1189
1190        options.no_cache = 1;
1191
1192        url = quote_ref_url(base, ref->name);
1193        if (http_get_strbuf(url, &buffer, &options) == HTTP_OK) {
1194                strbuf_rtrim(&buffer);
1195                if (buffer.len == 40)
1196                        ret = get_sha1_hex(buffer.buf, ref->old_sha1);
1197                else if (starts_with(buffer.buf, "ref: ")) {
1198                        ref->symref = xstrdup(buffer.buf + 5);
1199                        ret = 0;
1200                }
1201        }
1202
1203        strbuf_release(&buffer);
1204        free(url);
1205        return ret;
1206}
1207
1208/* Helpers for fetching packs */
1209static char *fetch_pack_index(unsigned char *sha1, const char *base_url)
1210{
1211        char *url, *tmp;
1212        struct strbuf buf = STRBUF_INIT;
1213
1214        if (http_is_verbose)
1215                fprintf(stderr, "Getting index for pack %s\n", sha1_to_hex(sha1));
1216
1217        end_url_with_slash(&buf, base_url);
1218        strbuf_addf(&buf, "objects/pack/pack-%s.idx", sha1_to_hex(sha1));
1219        url = strbuf_detach(&buf, NULL);
1220
1221        strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(sha1));
1222        tmp = strbuf_detach(&buf, NULL);
1223
1224        if (http_get_file(url, tmp, NULL) != HTTP_OK) {
1225                error("Unable to get pack index %s", url);
1226                free(tmp);
1227                tmp = NULL;
1228        }
1229
1230        free(url);
1231        return tmp;
1232}
1233
1234static int fetch_and_setup_pack_index(struct packed_git **packs_head,
1235        unsigned char *sha1, const char *base_url)
1236{
1237        struct packed_git *new_pack;
1238        char *tmp_idx = NULL;
1239        int ret;
1240
1241        if (has_pack_index(sha1)) {
1242                new_pack = parse_pack_index(sha1, NULL);
1243                if (!new_pack)
1244                        return -1; /* parse_pack_index() already issued error message */
1245                goto add_pack;
1246        }
1247
1248        tmp_idx = fetch_pack_index(sha1, base_url);
1249        if (!tmp_idx)
1250                return -1;
1251
1252        new_pack = parse_pack_index(sha1, tmp_idx);
1253        if (!new_pack) {
1254                unlink(tmp_idx);
1255                free(tmp_idx);
1256
1257                return -1; /* parse_pack_index() already issued error message */
1258        }
1259
1260        ret = verify_pack_index(new_pack);
1261        if (!ret) {
1262                close_pack_index(new_pack);
1263                ret = move_temp_to_file(tmp_idx, sha1_pack_index_name(sha1));
1264        }
1265        free(tmp_idx);
1266        if (ret)
1267                return -1;
1268
1269add_pack:
1270        new_pack->next = *packs_head;
1271        *packs_head = new_pack;
1272        return 0;
1273}
1274
1275int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
1276{
1277        struct http_get_options options = {0};
1278        int ret = 0, i = 0;
1279        char *url, *data;
1280        struct strbuf buf = STRBUF_INIT;
1281        unsigned char sha1[20];
1282
1283        end_url_with_slash(&buf, base_url);
1284        strbuf_addstr(&buf, "objects/info/packs");
1285        url = strbuf_detach(&buf, NULL);
1286
1287        options.no_cache = 1;
1288        ret = http_get_strbuf(url, &buf, &options);
1289        if (ret != HTTP_OK)
1290                goto cleanup;
1291
1292        data = buf.buf;
1293        while (i < buf.len) {
1294                switch (data[i]) {
1295                case 'P':
1296                        i++;
1297                        if (i + 52 <= buf.len &&
1298                            starts_with(data + i, " pack-") &&
1299                            starts_with(data + i + 46, ".pack\n")) {
1300                                get_sha1_hex(data + i + 6, sha1);
1301                                fetch_and_setup_pack_index(packs_head, sha1,
1302                                                      base_url);
1303                                i += 51;
1304                                break;
1305                        }
1306                default:
1307                        while (i < buf.len && data[i] != '\n')
1308                                i++;
1309                }
1310                i++;
1311        }
1312
1313cleanup:
1314        free(url);
1315        return ret;
1316}
1317
1318void release_http_pack_request(struct http_pack_request *preq)
1319{
1320        if (preq->packfile != NULL) {
1321                fclose(preq->packfile);
1322                preq->packfile = NULL;
1323        }
1324        if (preq->range_header != NULL) {
1325                curl_slist_free_all(preq->range_header);
1326                preq->range_header = NULL;
1327        }
1328        preq->slot = NULL;
1329        free(preq->url);
1330}
1331
1332int finish_http_pack_request(struct http_pack_request *preq)
1333{
1334        struct packed_git **lst;
1335        struct packed_git *p = preq->target;
1336        char *tmp_idx;
1337        struct child_process ip = CHILD_PROCESS_INIT;
1338        const char *ip_argv[8];
1339
1340        close_pack_index(p);
1341
1342        fclose(preq->packfile);
1343        preq->packfile = NULL;
1344
1345        lst = preq->lst;
1346        while (*lst != p)
1347                lst = &((*lst)->next);
1348        *lst = (*lst)->next;
1349
1350        tmp_idx = xstrdup(preq->tmpfile);
1351        strcpy(tmp_idx + strlen(tmp_idx) - strlen(".pack.temp"),
1352               ".idx.temp");
1353
1354        ip_argv[0] = "index-pack";
1355        ip_argv[1] = "-o";
1356        ip_argv[2] = tmp_idx;
1357        ip_argv[3] = preq->tmpfile;
1358        ip_argv[4] = NULL;
1359
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}