Andrew's git / gitweb.git / http.c
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http.con commit Merge branch 'maint' (6517452)
   1#include "http.h"
   2#include "pack.h"
   3
   4int data_received;
   5int active_requests;
   6int http_is_verbose;
   7
   8#ifdef USE_CURL_MULTI
   9static int max_requests = -1;
  10static CURLM *curlm;
  11#endif
  12#ifndef NO_CURL_EASY_DUPHANDLE
  13static CURL *curl_default;
  14#endif
  15
  16#define PREV_BUF_SIZE 4096
  17#define RANGE_HEADER_SIZE 30
  18
  19char curl_errorstr[CURL_ERROR_SIZE];
  20
  21static int curl_ssl_verify = -1;
  22static const char *ssl_cert;
  23#if LIBCURL_VERSION_NUM >= 0x070903
  24static const char *ssl_key;
  25#endif
  26#if LIBCURL_VERSION_NUM >= 0x070908
  27static const char *ssl_capath;
  28#endif
  29static const char *ssl_cainfo;
  30static long curl_low_speed_limit = -1;
  31static long curl_low_speed_time = -1;
  32static int curl_ftp_no_epsv;
  33static const char *curl_http_proxy;
  34static char *user_name, *user_pass;
  35
  36#if LIBCURL_VERSION_NUM >= 0x071700
  37/* Use CURLOPT_KEYPASSWD as is */
  38#elif LIBCURL_VERSION_NUM >= 0x070903
  39#define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
  40#else
  41#define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
  42#endif
  43
  44static char *ssl_cert_password;
  45static int ssl_cert_password_required;
  46
  47static struct curl_slist *pragma_header;
  48static struct curl_slist *no_pragma_header;
  49
  50static struct active_request_slot *active_queue_head;
  51
  52size_t fread_buffer(void *ptr, size_t eltsize, size_t nmemb, void *buffer_)
  53{
  54        size_t size = eltsize * nmemb;
  55        struct buffer *buffer = buffer_;
  56
  57        if (size > buffer->buf.len - buffer->posn)
  58                size = buffer->buf.len - buffer->posn;
  59        memcpy(ptr, buffer->buf.buf + buffer->posn, size);
  60        buffer->posn += size;
  61
  62        return size;
  63}
  64
  65#ifndef NO_CURL_IOCTL
  66curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
  67{
  68        struct buffer *buffer = clientp;
  69
  70        switch (cmd) {
  71        case CURLIOCMD_NOP:
  72                return CURLIOE_OK;
  73
  74        case CURLIOCMD_RESTARTREAD:
  75                buffer->posn = 0;
  76                return CURLIOE_OK;
  77
  78        default:
  79                return CURLIOE_UNKNOWNCMD;
  80        }
  81}
  82#endif
  83
  84size_t fwrite_buffer(const void *ptr, size_t eltsize, size_t nmemb, void *buffer_)
  85{
  86        size_t size = eltsize * nmemb;
  87        struct strbuf *buffer = buffer_;
  88
  89        strbuf_add(buffer, ptr, size);
  90        data_received++;
  91        return size;
  92}
  93
  94size_t fwrite_null(const void *ptr, size_t eltsize, size_t nmemb, void *strbuf)
  95{
  96        data_received++;
  97        return eltsize * nmemb;
  98}
  99
 100static void finish_active_slot(struct active_request_slot *slot);
 101
 102#ifdef USE_CURL_MULTI
 103static void process_curl_messages(void)
 104{
 105        int num_messages;
 106        struct active_request_slot *slot;
 107        CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
 108
 109        while (curl_message != NULL) {
 110                if (curl_message->msg == CURLMSG_DONE) {
 111                        int curl_result = curl_message->data.result;
 112                        slot = active_queue_head;
 113                        while (slot != NULL &&
 114                               slot->curl != curl_message->easy_handle)
 115                                slot = slot->next;
 116                        if (slot != NULL) {
 117                                curl_multi_remove_handle(curlm, slot->curl);
 118                                slot->curl_result = curl_result;
 119                                finish_active_slot(slot);
 120                        } else {
 121                                fprintf(stderr, "Received DONE message for unknown request!\n");
 122                        }
 123                } else {
 124                        fprintf(stderr, "Unknown CURL message received: %d\n",
 125                                (int)curl_message->msg);
 126                }
 127                curl_message = curl_multi_info_read(curlm, &num_messages);
 128        }
 129}
 130#endif
 131
 132static int http_options(const char *var, const char *value, void *cb)
 133{
 134        if (!strcmp("http.sslverify", var)) {
 135                curl_ssl_verify = git_config_bool(var, value);
 136                return 0;
 137        }
 138        if (!strcmp("http.sslcert", var))
 139                return git_config_string(&ssl_cert, var, value);
 140#if LIBCURL_VERSION_NUM >= 0x070903
 141        if (!strcmp("http.sslkey", var))
 142                return git_config_string(&ssl_key, var, value);
 143#endif
 144#if LIBCURL_VERSION_NUM >= 0x070908
 145        if (!strcmp("http.sslcapath", var))
 146                return git_config_string(&ssl_capath, var, value);
 147#endif
 148        if (!strcmp("http.sslcainfo", var))
 149                return git_config_string(&ssl_cainfo, var, value);
 150        if (!strcmp("http.sslcertpasswordprotected", var)) {
 151                if (git_config_bool(var, value))
 152                        ssl_cert_password_required = 1;
 153                return 0;
 154        }
 155#ifdef USE_CURL_MULTI
 156        if (!strcmp("http.maxrequests", var)) {
 157                max_requests = git_config_int(var, value);
 158                return 0;
 159        }
 160#endif
 161        if (!strcmp("http.lowspeedlimit", var)) {
 162                curl_low_speed_limit = (long)git_config_int(var, value);
 163                return 0;
 164        }
 165        if (!strcmp("http.lowspeedtime", var)) {
 166                curl_low_speed_time = (long)git_config_int(var, value);
 167                return 0;
 168        }
 169
 170        if (!strcmp("http.noepsv", var)) {
 171                curl_ftp_no_epsv = git_config_bool(var, value);
 172                return 0;
 173        }
 174        if (!strcmp("http.proxy", var))
 175                return git_config_string(&curl_http_proxy, var, value);
 176
 177        /* Fall back on the default ones */
 178        return git_default_config(var, value, cb);
 179}
 180
 181static void init_curl_http_auth(CURL *result)
 182{
 183        if (user_name) {
 184                struct strbuf up = STRBUF_INIT;
 185                if (!user_pass)
 186                        user_pass = xstrdup(getpass("Password: "));
 187                strbuf_addf(&up, "%s:%s", user_name, user_pass);
 188                curl_easy_setopt(result, CURLOPT_USERPWD,
 189                                 strbuf_detach(&up, NULL));
 190        }
 191}
 192
 193static int has_cert_password(void)
 194{
 195        if (ssl_cert_password != NULL)
 196                return 1;
 197        if (ssl_cert == NULL || ssl_cert_password_required != 1)
 198                return 0;
 199        /* Only prompt the user once. */
 200        ssl_cert_password_required = -1;
 201        ssl_cert_password = getpass("Certificate Password: ");
 202        if (ssl_cert_password != NULL) {
 203                ssl_cert_password = xstrdup(ssl_cert_password);
 204                return 1;
 205        } else
 206                return 0;
 207}
 208
 209static CURL *get_curl_handle(void)
 210{
 211        CURL *result = curl_easy_init();
 212
 213        if (!curl_ssl_verify) {
 214                curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
 215                curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
 216        } else {
 217                /* Verify authenticity of the peer's certificate */
 218                curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
 219                /* The name in the cert must match whom we tried to connect */
 220                curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
 221        }
 222
 223#if LIBCURL_VERSION_NUM >= 0x070907
 224        curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
 225#endif
 226
 227        init_curl_http_auth(result);
 228
 229        if (ssl_cert != NULL)
 230                curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
 231        if (has_cert_password())
 232                curl_easy_setopt(result, CURLOPT_KEYPASSWD, ssl_cert_password);
 233#if LIBCURL_VERSION_NUM >= 0x070903
 234        if (ssl_key != NULL)
 235                curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
 236#endif
 237#if LIBCURL_VERSION_NUM >= 0x070908
 238        if (ssl_capath != NULL)
 239                curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
 240#endif
 241        if (ssl_cainfo != NULL)
 242                curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
 243        curl_easy_setopt(result, CURLOPT_FAILONERROR, 1);
 244
 245        if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
 246                curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
 247                                 curl_low_speed_limit);
 248                curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
 249                                 curl_low_speed_time);
 250        }
 251
 252        curl_easy_setopt(result, CURLOPT_FOLLOWLOCATION, 1);
 253
 254        if (getenv("GIT_CURL_VERBOSE"))
 255                curl_easy_setopt(result, CURLOPT_VERBOSE, 1);
 256
 257        curl_easy_setopt(result, CURLOPT_USERAGENT, GIT_USER_AGENT);
 258
 259        if (curl_ftp_no_epsv)
 260                curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
 261
 262        if (curl_http_proxy)
 263                curl_easy_setopt(result, CURLOPT_PROXY, curl_http_proxy);
 264
 265        return result;
 266}
 267
 268static void http_auth_init(const char *url)
 269{
 270        char *at, *colon, *cp, *slash;
 271        int len;
 272
 273        cp = strstr(url, "://");
 274        if (!cp)
 275                return;
 276
 277        /*
 278         * Ok, the URL looks like "proto://something".  Which one?
 279         * "proto://<user>:<pass>@<host>/...",
 280         * "proto://<user>@<host>/...", or just
 281         * "proto://<host>/..."?
 282         */
 283        cp += 3;
 284        at = strchr(cp, '@');
 285        colon = strchr(cp, ':');
 286        slash = strchrnul(cp, '/');
 287        if (!at || slash <= at)
 288                return; /* No credentials */
 289        if (!colon || at <= colon) {
 290                /* Only username */
 291                len = at - cp;
 292                user_name = xmalloc(len + 1);
 293                memcpy(user_name, cp, len);
 294                user_name[len] = '\0';
 295                user_pass = NULL;
 296        } else {
 297                len = colon - cp;
 298                user_name = xmalloc(len + 1);
 299                memcpy(user_name, cp, len);
 300                user_name[len] = '\0';
 301                len = at - (colon + 1);
 302                user_pass = xmalloc(len + 1);
 303                memcpy(user_pass, colon + 1, len);
 304                user_pass[len] = '\0';
 305        }
 306}
 307
 308static void set_from_env(const char **var, const char *envname)
 309{
 310        const char *val = getenv(envname);
 311        if (val)
 312                *var = val;
 313}
 314
 315void http_init(struct remote *remote)
 316{
 317        char *low_speed_limit;
 318        char *low_speed_time;
 319
 320        http_is_verbose = 0;
 321
 322        git_config(http_options, NULL);
 323
 324        curl_global_init(CURL_GLOBAL_ALL);
 325
 326        if (remote && remote->http_proxy)
 327                curl_http_proxy = xstrdup(remote->http_proxy);
 328
 329        pragma_header = curl_slist_append(pragma_header, "Pragma: no-cache");
 330        no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
 331
 332#ifdef USE_CURL_MULTI
 333        {
 334                char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
 335                if (http_max_requests != NULL)
 336                        max_requests = atoi(http_max_requests);
 337        }
 338
 339        curlm = curl_multi_init();
 340        if (curlm == NULL) {
 341                fprintf(stderr, "Error creating curl multi handle.\n");
 342                exit(1);
 343        }
 344#endif
 345
 346        if (getenv("GIT_SSL_NO_VERIFY"))
 347                curl_ssl_verify = 0;
 348
 349        set_from_env(&ssl_cert, "GIT_SSL_CERT");
 350#if LIBCURL_VERSION_NUM >= 0x070903
 351        set_from_env(&ssl_key, "GIT_SSL_KEY");
 352#endif
 353#if LIBCURL_VERSION_NUM >= 0x070908
 354        set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
 355#endif
 356        set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
 357
 358        low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
 359        if (low_speed_limit != NULL)
 360                curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
 361        low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
 362        if (low_speed_time != NULL)
 363                curl_low_speed_time = strtol(low_speed_time, NULL, 10);
 364
 365        if (curl_ssl_verify == -1)
 366                curl_ssl_verify = 1;
 367
 368#ifdef USE_CURL_MULTI
 369        if (max_requests < 1)
 370                max_requests = DEFAULT_MAX_REQUESTS;
 371#endif
 372
 373        if (getenv("GIT_CURL_FTP_NO_EPSV"))
 374                curl_ftp_no_epsv = 1;
 375
 376        if (remote && remote->url && remote->url[0]) {
 377                http_auth_init(remote->url[0]);
 378                if (!ssl_cert_password_required &&
 379                    getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
 380                    !prefixcmp(remote->url[0], "https://"))
 381                        ssl_cert_password_required = 1;
 382        }
 383
 384#ifndef NO_CURL_EASY_DUPHANDLE
 385        curl_default = get_curl_handle();
 386#endif
 387}
 388
 389void http_cleanup(void)
 390{
 391        struct active_request_slot *slot = active_queue_head;
 392
 393        while (slot != NULL) {
 394                struct active_request_slot *next = slot->next;
 395                if (slot->curl != NULL) {
 396#ifdef USE_CURL_MULTI
 397                        curl_multi_remove_handle(curlm, slot->curl);
 398#endif
 399                        curl_easy_cleanup(slot->curl);
 400                }
 401                free(slot);
 402                slot = next;
 403        }
 404        active_queue_head = NULL;
 405
 406#ifndef NO_CURL_EASY_DUPHANDLE
 407        curl_easy_cleanup(curl_default);
 408#endif
 409
 410#ifdef USE_CURL_MULTI
 411        curl_multi_cleanup(curlm);
 412#endif
 413        curl_global_cleanup();
 414
 415        curl_slist_free_all(pragma_header);
 416        pragma_header = NULL;
 417
 418        curl_slist_free_all(no_pragma_header);
 419        no_pragma_header = NULL;
 420
 421        if (curl_http_proxy) {
 422                free((void *)curl_http_proxy);
 423                curl_http_proxy = NULL;
 424        }
 425
 426        if (ssl_cert_password != NULL) {
 427                memset(ssl_cert_password, 0, strlen(ssl_cert_password));
 428                free(ssl_cert_password);
 429                ssl_cert_password = NULL;
 430        }
 431        ssl_cert_password_required = 0;
 432}
 433
 434struct active_request_slot *get_active_slot(void)
 435{
 436        struct active_request_slot *slot = active_queue_head;
 437        struct active_request_slot *newslot;
 438
 439#ifdef USE_CURL_MULTI
 440        int num_transfers;
 441
 442        /* Wait for a slot to open up if the queue is full */
 443        while (active_requests >= max_requests) {
 444                curl_multi_perform(curlm, &num_transfers);
 445                if (num_transfers < active_requests)
 446                        process_curl_messages();
 447        }
 448#endif
 449
 450        while (slot != NULL && slot->in_use)
 451                slot = slot->next;
 452
 453        if (slot == NULL) {
 454                newslot = xmalloc(sizeof(*newslot));
 455                newslot->curl = NULL;
 456                newslot->in_use = 0;
 457                newslot->next = NULL;
 458
 459                slot = active_queue_head;
 460                if (slot == NULL) {
 461                        active_queue_head = newslot;
 462                } else {
 463                        while (slot->next != NULL)
 464                                slot = slot->next;
 465                        slot->next = newslot;
 466                }
 467                slot = newslot;
 468        }
 469
 470        if (slot->curl == NULL) {
 471#ifdef NO_CURL_EASY_DUPHANDLE
 472                slot->curl = get_curl_handle();
 473#else
 474                slot->curl = curl_easy_duphandle(curl_default);
 475#endif
 476        }
 477
 478        active_requests++;
 479        slot->in_use = 1;
 480        slot->local = NULL;
 481        slot->results = NULL;
 482        slot->finished = NULL;
 483        slot->callback_data = NULL;
 484        slot->callback_func = NULL;
 485        curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
 486        curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
 487        curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
 488        curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
 489        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
 490        curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
 491        curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 492
 493        return slot;
 494}
 495
 496int start_active_slot(struct active_request_slot *slot)
 497{
 498#ifdef USE_CURL_MULTI
 499        CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
 500        int num_transfers;
 501
 502        if (curlm_result != CURLM_OK &&
 503            curlm_result != CURLM_CALL_MULTI_PERFORM) {
 504                active_requests--;
 505                slot->in_use = 0;
 506                return 0;
 507        }
 508
 509        /*
 510         * We know there must be something to do, since we just added
 511         * something.
 512         */
 513        curl_multi_perform(curlm, &num_transfers);
 514#endif
 515        return 1;
 516}
 517
 518#ifdef USE_CURL_MULTI
 519struct fill_chain {
 520        void *data;
 521        int (*fill)(void *);
 522        struct fill_chain *next;
 523};
 524
 525static struct fill_chain *fill_cfg;
 526
 527void add_fill_function(void *data, int (*fill)(void *))
 528{
 529        struct fill_chain *new = xmalloc(sizeof(*new));
 530        struct fill_chain **linkp = &fill_cfg;
 531        new->data = data;
 532        new->fill = fill;
 533        new->next = NULL;
 534        while (*linkp)
 535                linkp = &(*linkp)->next;
 536        *linkp = new;
 537}
 538
 539void fill_active_slots(void)
 540{
 541        struct active_request_slot *slot = active_queue_head;
 542
 543        while (active_requests < max_requests) {
 544                struct fill_chain *fill;
 545                for (fill = fill_cfg; fill; fill = fill->next)
 546                        if (fill->fill(fill->data))
 547                                break;
 548
 549                if (!fill)
 550                        break;
 551        }
 552
 553        while (slot != NULL) {
 554                if (!slot->in_use && slot->curl != NULL) {
 555                        curl_easy_cleanup(slot->curl);
 556                        slot->curl = NULL;
 557                }
 558                slot = slot->next;
 559        }
 560}
 561
 562void step_active_slots(void)
 563{
 564        int num_transfers;
 565        CURLMcode curlm_result;
 566
 567        do {
 568                curlm_result = curl_multi_perform(curlm, &num_transfers);
 569        } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
 570        if (num_transfers < active_requests) {
 571                process_curl_messages();
 572                fill_active_slots();
 573        }
 574}
 575#endif
 576
 577void run_active_slot(struct active_request_slot *slot)
 578{
 579#ifdef USE_CURL_MULTI
 580        long last_pos = 0;
 581        long current_pos;
 582        fd_set readfds;
 583        fd_set writefds;
 584        fd_set excfds;
 585        int max_fd;
 586        struct timeval select_timeout;
 587        int finished = 0;
 588
 589        slot->finished = &finished;
 590        while (!finished) {
 591                data_received = 0;
 592                step_active_slots();
 593
 594                if (!data_received && slot->local != NULL) {
 595                        current_pos = ftell(slot->local);
 596                        if (current_pos > last_pos)
 597                                data_received++;
 598                        last_pos = current_pos;
 599                }
 600
 601                if (slot->in_use && !data_received) {
 602                        max_fd = 0;
 603                        FD_ZERO(&readfds);
 604                        FD_ZERO(&writefds);
 605                        FD_ZERO(&excfds);
 606                        select_timeout.tv_sec = 0;
 607                        select_timeout.tv_usec = 50000;
 608                        select(max_fd, &readfds, &writefds,
 609                               &excfds, &select_timeout);
 610                }
 611        }
 612#else
 613        while (slot->in_use) {
 614                slot->curl_result = curl_easy_perform(slot->curl);
 615                finish_active_slot(slot);
 616        }
 617#endif
 618}
 619
 620static void closedown_active_slot(struct active_request_slot *slot)
 621{
 622        active_requests--;
 623        slot->in_use = 0;
 624}
 625
 626void release_active_slot(struct active_request_slot *slot)
 627{
 628        closedown_active_slot(slot);
 629        if (slot->curl) {
 630#ifdef USE_CURL_MULTI
 631                curl_multi_remove_handle(curlm, slot->curl);
 632#endif
 633                curl_easy_cleanup(slot->curl);
 634                slot->curl = NULL;
 635        }
 636#ifdef USE_CURL_MULTI
 637        fill_active_slots();
 638#endif
 639}
 640
 641static void finish_active_slot(struct active_request_slot *slot)
 642{
 643        closedown_active_slot(slot);
 644        curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
 645
 646        if (slot->finished != NULL)
 647                (*slot->finished) = 1;
 648
 649        /* Store slot results so they can be read after the slot is reused */
 650        if (slot->results != NULL) {
 651                slot->results->curl_result = slot->curl_result;
 652                slot->results->http_code = slot->http_code;
 653        }
 654
 655        /* Run callback if appropriate */
 656        if (slot->callback_func != NULL)
 657                slot->callback_func(slot->callback_data);
 658}
 659
 660void finish_all_active_slots(void)
 661{
 662        struct active_request_slot *slot = active_queue_head;
 663
 664        while (slot != NULL)
 665                if (slot->in_use) {
 666                        run_active_slot(slot);
 667                        slot = active_queue_head;
 668                } else {
 669                        slot = slot->next;
 670                }
 671}
 672
 673/* Helpers for modifying and creating URLs */
 674static inline int needs_quote(int ch)
 675{
 676        if (((ch >= 'A') && (ch <= 'Z'))
 677                        || ((ch >= 'a') && (ch <= 'z'))
 678                        || ((ch >= '0') && (ch <= '9'))
 679                        || (ch == '/')
 680                        || (ch == '-')
 681                        || (ch == '.'))
 682                return 0;
 683        return 1;
 684}
 685
 686static inline int hex(int v)
 687{
 688        if (v < 10)
 689                return '0' + v;
 690        else
 691                return 'A' + v - 10;
 692}
 693
 694static void end_url_with_slash(struct strbuf *buf, const char *url)
 695{
 696        strbuf_addstr(buf, url);
 697        if (buf->len && buf->buf[buf->len - 1] != '/')
 698                strbuf_addstr(buf, "/");
 699}
 700
 701static char *quote_ref_url(const char *base, const char *ref)
 702{
 703        struct strbuf buf = STRBUF_INIT;
 704        const char *cp;
 705        int ch;
 706
 707        end_url_with_slash(&buf, base);
 708
 709        for (cp = ref; (ch = *cp) != 0; cp++)
 710                if (needs_quote(ch))
 711                        strbuf_addf(&buf, "%%%02x", ch);
 712                else
 713                        strbuf_addch(&buf, *cp);
 714
 715        return strbuf_detach(&buf, NULL);
 716}
 717
 718void append_remote_object_url(struct strbuf *buf, const char *url,
 719                              const char *hex,
 720                              int only_two_digit_prefix)
 721{
 722        strbuf_addf(buf, "%s/objects/%.*s/", url, 2, hex);
 723        if (!only_two_digit_prefix)
 724                strbuf_addf(buf, "%s", hex+2);
 725}
 726
 727char *get_remote_object_url(const char *url, const char *hex,
 728                            int only_two_digit_prefix)
 729{
 730        struct strbuf buf = STRBUF_INIT;
 731        append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
 732        return strbuf_detach(&buf, NULL);
 733}
 734
 735/* http_request() targets */
 736#define HTTP_REQUEST_STRBUF     0
 737#define HTTP_REQUEST_FILE       1
 738
 739static int http_request(const char *url, void *result, int target, int options)
 740{
 741        struct active_request_slot *slot;
 742        struct slot_results results;
 743        struct curl_slist *headers = NULL;
 744        struct strbuf buf = STRBUF_INIT;
 745        int ret;
 746
 747        slot = get_active_slot();
 748        slot->results = &results;
 749        curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 750
 751        if (result == NULL) {
 752                curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
 753        } else {
 754                curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
 755                curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
 756
 757                if (target == HTTP_REQUEST_FILE) {
 758                        long posn = ftell(result);
 759                        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
 760                                         fwrite);
 761                        if (posn > 0) {
 762                                strbuf_addf(&buf, "Range: bytes=%ld-", posn);
 763                                headers = curl_slist_append(headers, buf.buf);
 764                                strbuf_reset(&buf);
 765                        }
 766                        slot->local = result;
 767                } else
 768                        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
 769                                         fwrite_buffer);
 770        }
 771
 772        strbuf_addstr(&buf, "Pragma:");
 773        if (options & HTTP_NO_CACHE)
 774                strbuf_addstr(&buf, " no-cache");
 775
 776        headers = curl_slist_append(headers, buf.buf);
 777
 778        curl_easy_setopt(slot->curl, CURLOPT_URL, url);
 779        curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
 780
 781        if (start_active_slot(slot)) {
 782                run_active_slot(slot);
 783                if (results.curl_result == CURLE_OK)
 784                        ret = HTTP_OK;
 785                else if (missing_target(&results))
 786                        ret = HTTP_MISSING_TARGET;
 787                else
 788                        ret = HTTP_ERROR;
 789        } else {
 790                error("Unable to start HTTP request for %s", url);
 791                ret = HTTP_START_FAILED;
 792        }
 793
 794        slot->local = NULL;
 795        curl_slist_free_all(headers);
 796        strbuf_release(&buf);
 797
 798        return ret;
 799}
 800
 801int http_get_strbuf(const char *url, struct strbuf *result, int options)
 802{
 803        return http_request(url, result, HTTP_REQUEST_STRBUF, options);
 804}
 805
 806int http_get_file(const char *url, const char *filename, int options)
 807{
 808        int ret;
 809        struct strbuf tmpfile = STRBUF_INIT;
 810        FILE *result;
 811
 812        strbuf_addf(&tmpfile, "%s.temp", filename);
 813        result = fopen(tmpfile.buf, "a");
 814        if (! result) {
 815                error("Unable to open local file %s", tmpfile.buf);
 816                ret = HTTP_ERROR;
 817                goto cleanup;
 818        }
 819
 820        ret = http_request(url, result, HTTP_REQUEST_FILE, options);
 821        fclose(result);
 822
 823        if ((ret == HTTP_OK) && move_temp_to_file(tmpfile.buf, filename))
 824                ret = HTTP_ERROR;
 825cleanup:
 826        strbuf_release(&tmpfile);
 827        return ret;
 828}
 829
 830int http_error(const char *url, int ret)
 831{
 832        /* http_request has already handled HTTP_START_FAILED. */
 833        if (ret != HTTP_START_FAILED)
 834                error("%s while accessing %s\n", curl_errorstr, url);
 835
 836        return ret;
 837}
 838
 839int http_fetch_ref(const char *base, struct ref *ref)
 840{
 841        char *url;
 842        struct strbuf buffer = STRBUF_INIT;
 843        int ret = -1;
 844
 845        url = quote_ref_url(base, ref->name);
 846        if (http_get_strbuf(url, &buffer, HTTP_NO_CACHE) == HTTP_OK) {
 847                strbuf_rtrim(&buffer);
 848                if (buffer.len == 40)
 849                        ret = get_sha1_hex(buffer.buf, ref->old_sha1);
 850                else if (!prefixcmp(buffer.buf, "ref: ")) {
 851                        ref->symref = xstrdup(buffer.buf + 5);
 852                        ret = 0;
 853                }
 854        }
 855
 856        strbuf_release(&buffer);
 857        free(url);
 858        return ret;
 859}
 860
 861/* Helpers for fetching packs */
 862static int fetch_pack_index(unsigned char *sha1, const char *base_url)
 863{
 864        int ret = 0;
 865        char *hex = xstrdup(sha1_to_hex(sha1));
 866        char *filename;
 867        char *url;
 868        struct strbuf buf = STRBUF_INIT;
 869
 870        /* Don't use the index if the pack isn't there */
 871        end_url_with_slash(&buf, base_url);
 872        strbuf_addf(&buf, "objects/pack/pack-%s.pack", hex);
 873        url = strbuf_detach(&buf, 0);
 874
 875        if (http_get_strbuf(url, NULL, 0)) {
 876                ret = error("Unable to verify pack %s is available",
 877                            hex);
 878                goto cleanup;
 879        }
 880
 881        if (has_pack_index(sha1)) {
 882                ret = 0;
 883                goto cleanup;
 884        }
 885
 886        if (http_is_verbose)
 887                fprintf(stderr, "Getting index for pack %s\n", hex);
 888
 889        end_url_with_slash(&buf, base_url);
 890        strbuf_addf(&buf, "objects/pack/pack-%s.idx", hex);
 891        url = strbuf_detach(&buf, NULL);
 892
 893        filename = sha1_pack_index_name(sha1);
 894        if (http_get_file(url, filename, 0) != HTTP_OK)
 895                ret = error("Unable to get pack index %s\n", url);
 896
 897cleanup:
 898        free(hex);
 899        free(url);
 900        return ret;
 901}
 902
 903static int fetch_and_setup_pack_index(struct packed_git **packs_head,
 904        unsigned char *sha1, const char *base_url)
 905{
 906        struct packed_git *new_pack;
 907
 908        if (fetch_pack_index(sha1, base_url))
 909                return -1;
 910
 911        new_pack = parse_pack_index(sha1);
 912        if (!new_pack)
 913                return -1; /* parse_pack_index() already issued error message */
 914        new_pack->next = *packs_head;
 915        *packs_head = new_pack;
 916        return 0;
 917}
 918
 919int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
 920{
 921        int ret = 0, i = 0;
 922        char *url, *data;
 923        struct strbuf buf = STRBUF_INIT;
 924        unsigned char sha1[20];
 925
 926        end_url_with_slash(&buf, base_url);
 927        strbuf_addstr(&buf, "objects/info/packs");
 928        url = strbuf_detach(&buf, NULL);
 929
 930        ret = http_get_strbuf(url, &buf, HTTP_NO_CACHE);
 931        if (ret != HTTP_OK)
 932                goto cleanup;
 933
 934        data = buf.buf;
 935        while (i < buf.len) {
 936                switch (data[i]) {
 937                case 'P':
 938                        i++;
 939                        if (i + 52 <= buf.len &&
 940                            !prefixcmp(data + i, " pack-") &&
 941                            !prefixcmp(data + i + 46, ".pack\n")) {
 942                                get_sha1_hex(data + i + 6, sha1);
 943                                fetch_and_setup_pack_index(packs_head, sha1,
 944                                                      base_url);
 945                                i += 51;
 946                                break;
 947                        }
 948                default:
 949                        while (i < buf.len && data[i] != '\n')
 950                                i++;
 951                }
 952                i++;
 953        }
 954
 955cleanup:
 956        free(url);
 957        return ret;
 958}
 959
 960void release_http_pack_request(struct http_pack_request *preq)
 961{
 962        if (preq->packfile != NULL) {
 963                fclose(preq->packfile);
 964                preq->packfile = NULL;
 965                preq->slot->local = NULL;
 966        }
 967        if (preq->range_header != NULL) {
 968                curl_slist_free_all(preq->range_header);
 969                preq->range_header = NULL;
 970        }
 971        preq->slot = NULL;
 972        free(preq->url);
 973}
 974
 975int finish_http_pack_request(struct http_pack_request *preq)
 976{
 977        int ret;
 978        struct packed_git **lst;
 979
 980        preq->target->pack_size = ftell(preq->packfile);
 981
 982        if (preq->packfile != NULL) {
 983                fclose(preq->packfile);
 984                preq->packfile = NULL;
 985                preq->slot->local = NULL;
 986        }
 987
 988        ret = move_temp_to_file(preq->tmpfile, preq->filename);
 989        if (ret)
 990                return ret;
 991
 992        lst = preq->lst;
 993        while (*lst != preq->target)
 994                lst = &((*lst)->next);
 995        *lst = (*lst)->next;
 996
 997        if (verify_pack(preq->target))
 998                return -1;
 999        install_packed_git(preq->target);
1000
1001        return 0;
1002}
1003
1004struct http_pack_request *new_http_pack_request(
1005        struct packed_git *target, const char *base_url)
1006{
1007        char *url;
1008        char *filename;
1009        long prev_posn = 0;
1010        char range[RANGE_HEADER_SIZE];
1011        struct strbuf buf = STRBUF_INIT;
1012        struct http_pack_request *preq;
1013
1014        preq = xmalloc(sizeof(*preq));
1015        preq->target = target;
1016        preq->range_header = NULL;
1017
1018        end_url_with_slash(&buf, base_url);
1019        strbuf_addf(&buf, "objects/pack/pack-%s.pack",
1020                sha1_to_hex(target->sha1));
1021        url = strbuf_detach(&buf, NULL);
1022        preq->url = xstrdup(url);
1023
1024        filename = sha1_pack_name(target->sha1);
1025        snprintf(preq->filename, sizeof(preq->filename), "%s", filename);
1026        snprintf(preq->tmpfile, sizeof(preq->tmpfile), "%s.temp", filename);
1027        preq->packfile = fopen(preq->tmpfile, "a");
1028        if (!preq->packfile) {
1029                error("Unable to open local file %s for pack",
1030                      preq->tmpfile);
1031                goto abort;
1032        }
1033
1034        preq->slot = get_active_slot();
1035        preq->slot->local = preq->packfile;
1036        curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
1037        curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
1038        curl_easy_setopt(preq->slot->curl, CURLOPT_URL, url);
1039        curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1040                no_pragma_header);
1041
1042        /*
1043         * If there is data present from a previous transfer attempt,
1044         * resume where it left off
1045         */
1046        prev_posn = ftell(preq->packfile);
1047        if (prev_posn>0) {
1048                if (http_is_verbose)
1049                        fprintf(stderr,
1050                                "Resuming fetch of pack %s at byte %ld\n",
1051                                sha1_to_hex(target->sha1), prev_posn);
1052                sprintf(range, "Range: bytes=%ld-", prev_posn);
1053                preq->range_header = curl_slist_append(NULL, range);
1054                curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1055                        preq->range_header);
1056        }
1057
1058        return preq;
1059
1060abort:
1061        free(filename);
1062        return NULL;
1063}
1064
1065/* Helpers for fetching objects (loose) */
1066static size_t fwrite_sha1_file(void *ptr, size_t eltsize, size_t nmemb,
1067                               void *data)
1068{
1069        unsigned char expn[4096];
1070        size_t size = eltsize * nmemb;
1071        int posn = 0;
1072        struct http_object_request *freq =
1073                (struct http_object_request *)data;
1074        do {
1075                ssize_t retval = xwrite(freq->localfile,
1076                                        (char *) ptr + posn, size - posn);
1077                if (retval < 0)
1078                        return posn;
1079                posn += retval;
1080        } while (posn < size);
1081
1082        freq->stream.avail_in = size;
1083        freq->stream.next_in = ptr;
1084        do {
1085                freq->stream.next_out = expn;
1086                freq->stream.avail_out = sizeof(expn);
1087                freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
1088                git_SHA1_Update(&freq->c, expn,
1089                                sizeof(expn) - freq->stream.avail_out);
1090        } while (freq->stream.avail_in && freq->zret == Z_OK);
1091        data_received++;
1092        return size;
1093}
1094
1095struct http_object_request *new_http_object_request(const char *base_url,
1096        unsigned char *sha1)
1097{
1098        char *hex = sha1_to_hex(sha1);
1099        char *filename;
1100        char prevfile[PATH_MAX];
1101        char *url;
1102        int prevlocal;
1103        unsigned char prev_buf[PREV_BUF_SIZE];
1104        ssize_t prev_read = 0;
1105        long prev_posn = 0;
1106        char range[RANGE_HEADER_SIZE];
1107        struct curl_slist *range_header = NULL;
1108        struct http_object_request *freq;
1109
1110        freq = xmalloc(sizeof(*freq));
1111        hashcpy(freq->sha1, sha1);
1112        freq->localfile = -1;
1113
1114        filename = sha1_file_name(sha1);
1115        snprintf(freq->filename, sizeof(freq->filename), "%s", filename);
1116        snprintf(freq->tmpfile, sizeof(freq->tmpfile),
1117                 "%s.temp", filename);
1118
1119        snprintf(prevfile, sizeof(prevfile), "%s.prev", filename);
1120        unlink_or_warn(prevfile);
1121        rename(freq->tmpfile, prevfile);
1122        unlink_or_warn(freq->tmpfile);
1123
1124        if (freq->localfile != -1)
1125                error("fd leakage in start: %d", freq->localfile);
1126        freq->localfile = open(freq->tmpfile,
1127                               O_WRONLY | O_CREAT | O_EXCL, 0666);
1128        /*
1129         * This could have failed due to the "lazy directory creation";
1130         * try to mkdir the last path component.
1131         */
1132        if (freq->localfile < 0 && errno == ENOENT) {
1133                char *dir = strrchr(freq->tmpfile, '/');
1134                if (dir) {
1135                        *dir = 0;
1136                        mkdir(freq->tmpfile, 0777);
1137                        *dir = '/';
1138                }
1139                freq->localfile = open(freq->tmpfile,
1140                                       O_WRONLY | O_CREAT | O_EXCL, 0666);
1141        }
1142
1143        if (freq->localfile < 0) {
1144                error("Couldn't create temporary file %s for %s: %s",
1145                      freq->tmpfile, freq->filename, strerror(errno));
1146                goto abort;
1147        }
1148
1149        memset(&freq->stream, 0, sizeof(freq->stream));
1150
1151        git_inflate_init(&freq->stream);
1152
1153        git_SHA1_Init(&freq->c);
1154
1155        url = get_remote_object_url(base_url, hex, 0);
1156        freq->url = xstrdup(url);
1157
1158        /*
1159         * If a previous temp file is present, process what was already
1160         * fetched.
1161         */
1162        prevlocal = open(prevfile, O_RDONLY);
1163        if (prevlocal != -1) {
1164                do {
1165                        prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
1166                        if (prev_read>0) {
1167                                if (fwrite_sha1_file(prev_buf,
1168                                                     1,
1169                                                     prev_read,
1170                                                     freq) == prev_read) {
1171                                        prev_posn += prev_read;
1172                                } else {
1173                                        prev_read = -1;
1174                                }
1175                        }
1176                } while (prev_read > 0);
1177                close(prevlocal);
1178        }
1179        unlink_or_warn(prevfile);
1180
1181        /*
1182         * Reset inflate/SHA1 if there was an error reading the previous temp
1183         * file; also rewind to the beginning of the local file.
1184         */
1185        if (prev_read == -1) {
1186                memset(&freq->stream, 0, sizeof(freq->stream));
1187                git_inflate_init(&freq->stream);
1188                git_SHA1_Init(&freq->c);
1189                if (prev_posn>0) {
1190                        prev_posn = 0;
1191                        lseek(freq->localfile, 0, SEEK_SET);
1192                        ftruncate(freq->localfile, 0);
1193                }
1194        }
1195
1196        freq->slot = get_active_slot();
1197
1198        curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
1199        curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
1200        curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
1201        curl_easy_setopt(freq->slot->curl, CURLOPT_URL, url);
1202        curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
1203
1204        /*
1205         * If we have successfully processed data from a previous fetch
1206         * attempt, only fetch the data we don't already have.
1207         */
1208        if (prev_posn>0) {
1209                if (http_is_verbose)
1210                        fprintf(stderr,
1211                                "Resuming fetch of object %s at byte %ld\n",
1212                                hex, prev_posn);
1213                sprintf(range, "Range: bytes=%ld-", prev_posn);
1214                range_header = curl_slist_append(range_header, range);
1215                curl_easy_setopt(freq->slot->curl,
1216                                 CURLOPT_HTTPHEADER, range_header);
1217        }
1218
1219        return freq;
1220
1221        free(url);
1222abort:
1223        free(filename);
1224        free(freq);
1225        return NULL;
1226}
1227
1228void process_http_object_request(struct http_object_request *freq)
1229{
1230        if (freq->slot == NULL)
1231                return;
1232        freq->curl_result = freq->slot->curl_result;
1233        freq->http_code = freq->slot->http_code;
1234        freq->slot = NULL;
1235}
1236
1237int finish_http_object_request(struct http_object_request *freq)
1238{
1239        struct stat st;
1240
1241        close(freq->localfile);
1242        freq->localfile = -1;
1243
1244        process_http_object_request(freq);
1245
1246        if (freq->http_code == 416) {
1247                fprintf(stderr, "Warning: requested range invalid; we may already have all the data.\n");
1248        } else if (freq->curl_result != CURLE_OK) {
1249                if (stat(freq->tmpfile, &st) == 0)
1250                        if (st.st_size == 0)
1251                                unlink_or_warn(freq->tmpfile);
1252                return -1;
1253        }
1254
1255        git_inflate_end(&freq->stream);
1256        git_SHA1_Final(freq->real_sha1, &freq->c);
1257        if (freq->zret != Z_STREAM_END) {
1258                unlink_or_warn(freq->tmpfile);
1259                return -1;
1260        }
1261        if (hashcmp(freq->sha1, freq->real_sha1)) {
1262                unlink_or_warn(freq->tmpfile);
1263                return -1;
1264        }
1265        freq->rename =
1266                move_temp_to_file(freq->tmpfile, freq->filename);
1267
1268        return freq->rename;
1269}
1270
1271void abort_http_object_request(struct http_object_request *freq)
1272{
1273        unlink_or_warn(freq->tmpfile);
1274
1275        release_http_object_request(freq);
1276}
1277
1278void release_http_object_request(struct http_object_request *freq)
1279{
1280        if (freq->localfile != -1) {
1281                close(freq->localfile);
1282                freq->localfile = -1;
1283        }
1284        if (freq->url != NULL) {
1285                free(freq->url);
1286                freq->url = NULL;
1287        }
1288        freq->slot = NULL;
1289}