Andrew's git - gitweb.git/blob

0b01877b5c1b564b1fe65b7a960a73829a6479d6
   1#include "cache.h"
   2#include "commit.h"
   3#include "pack.h"
   4#include "fetch.h"
   5
   6#include <curl/curl.h>
   7#include <curl/easy.h>
   8
   9#define DEFAULT_MAX_REQUESTS 5
  10
  11#if LIBCURL_VERSION_NUM < 0x070704
  12#define curl_global_cleanup() do { /* nothing */ } while(0)
  13#endif
  14#if LIBCURL_VERSION_NUM < 0x070800
  15#define curl_global_init(a) do { /* nothing */ } while(0)
  16#endif
  17
  18#define PREV_BUF_SIZE 4096
  19#define RANGE_HEADER_SIZE 30
  20
  21static int max_requests = DEFAULT_MAX_REQUESTS;
  22static int active_requests = 0;
  23static int data_received;
  24
  25static CURLM *curlm;
  26static CURL *curl_default;
  27static struct curl_slist *no_pragma_header;
  28static struct curl_slist *no_range_header;
  29static char curl_errorstr[CURL_ERROR_SIZE];
  30
  31struct alt_base
  32{
  33        char *base;
  34        int got_indices;
  35        struct packed_git *packs;
  36        struct alt_base *next;
  37};
  38
  39static struct alt_base *alt = NULL;
  40
  41enum transfer_state {
  42        WAITING,
  43        ABORTED,
  44        ACTIVE,
  45        COMPLETE,
  46};
  47
  48struct transfer_request
  49{
  50        unsigned char sha1[20];
  51        struct alt_base *repo;
  52        char *url;
  53        char filename[PATH_MAX];
  54        char tmpfile[PATH_MAX];
  55        int local;
  56        enum transfer_state state;
  57        CURLcode curl_result;
  58        char errorstr[CURL_ERROR_SIZE];
  59        long http_code;
  60        unsigned char real_sha1[20];
  61        SHA_CTX c;
  62        z_stream stream;
  63        int zret;
  64        int rename;
  65        struct active_request_slot *slot;
  66        struct transfer_request *next;
  67};
  68
  69struct active_request_slot
  70{
  71        CURL *curl;
  72        FILE *local;
  73        int in_use;
  74        int done;
  75        CURLcode curl_result;
  76        struct active_request_slot *next;
  77};
  78
  79static struct transfer_request *request_queue_head = NULL;
  80static struct active_request_slot *active_queue_head = NULL;
  81
  82static int curl_ssl_verify;
  83static char *ssl_cert;
  84static char *ssl_key;
  85static char *ssl_capath;
  86static char *ssl_cainfo;
  87
  88struct buffer
  89{
  90        size_t posn;
  91        size_t size;
  92        void *buffer;
  93};
  94
  95static size_t fwrite_buffer(void *ptr, size_t eltsize, size_t nmemb,
  96                            struct buffer *buffer)
  97{
  98        size_t size = eltsize * nmemb;
  99        if (size > buffer->size - buffer->posn)
 100                size = buffer->size - buffer->posn;
 101        memcpy(buffer->buffer + buffer->posn, ptr, size);
 102        buffer->posn += size;
 103        data_received++;
 104        return size;
 105}
 106
 107static size_t fwrite_sha1_file(void *ptr, size_t eltsize, size_t nmemb,
 108                               void *data)
 109{
 110        unsigned char expn[4096];
 111        size_t size = eltsize * nmemb;
 112        int posn = 0;
 113        struct transfer_request *request = (struct transfer_request *)data;
 114        do {
 115                ssize_t retval = write(request->local,
 116                                       ptr + posn, size - posn);
 117                if (retval < 0)
 118                        return posn;
 119                posn += retval;
 120        } while (posn < size);
 121
 122        request->stream.avail_in = size;
 123        request->stream.next_in = ptr;
 124        do {
 125                request->stream.next_out = expn;
 126                request->stream.avail_out = sizeof(expn);
 127                request->zret = inflate(&request->stream, Z_SYNC_FLUSH);
 128                SHA1_Update(&request->c, expn,
 129                            sizeof(expn) - request->stream.avail_out);
 130        } while (request->stream.avail_in && request->zret == Z_OK);
 131        data_received++;
 132        return size;
 133}
 134
 135int relink_or_rename(char *old, char *new) {
 136        int ret;
 137
 138        ret = link(old, new);
 139        if (ret < 0) {
 140                /* Same Coda hack as in write_sha1_file(sha1_file.c) */
 141                ret = errno;
 142                if (ret == EXDEV && !rename(old, new))
 143                        return 0;
 144        }
 145        unlink(old);
 146        if (ret) {
 147                if (ret != EEXIST)
 148                        return ret;
 149        }
 150
 151        return 0;
 152}
 153
 154void process_curl_messages();
 155void process_request_queue();
 156
 157struct active_request_slot *get_active_slot()
 158{
 159        struct active_request_slot *slot = active_queue_head;
 160        struct active_request_slot *newslot;
 161        int num_transfers;
 162
 163        /* Wait for a slot to open up if the queue is full */
 164        while (active_requests >= max_requests) {
 165                curl_multi_perform(curlm, &num_transfers);
 166                if (num_transfers < active_requests) {
 167                        process_curl_messages();
 168                }
 169        }
 170
 171        while (slot != NULL && slot->in_use) {
 172                slot = slot->next;
 173        }
 174        if (slot == NULL) {
 175                newslot = xmalloc(sizeof(*newslot));
 176                newslot->curl = curl_easy_duphandle(curl_default);
 177                newslot->in_use = 0;
 178                newslot->next = NULL;
 179
 180                slot = active_queue_head;
 181                if (slot == NULL) {
 182                        active_queue_head = newslot;
 183                } else {
 184                        while (slot->next != NULL) {
 185                                slot = slot->next;
 186                        }
 187                        slot->next = newslot;
 188                }
 189                slot = newslot;
 190        }
 191
 192        active_requests++;
 193        slot->in_use = 1;
 194        slot->done = 0;
 195        slot->local = NULL;
 196        curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
 197        curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, no_range_header);
 198        curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
 199
 200        return slot;
 201}
 202
 203int start_active_slot(struct active_request_slot *slot)
 204{
 205        CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
 206
 207        if (curlm_result != CURLM_OK &&
 208            curlm_result != CURLM_CALL_MULTI_PERFORM) {
 209                active_requests--;
 210                slot->in_use = 0;
 211                return 0;
 212        }
 213
 214        return 1;
 215}
 216
 217void run_active_slot(struct active_request_slot *slot)
 218{
 219        int num_transfers;
 220        long last_pos = 0;
 221        long current_pos;
 222        fd_set readfds;
 223        fd_set writefds;
 224        fd_set excfds;
 225        int max_fd;
 226        struct timeval select_timeout;
 227        CURLMcode curlm_result;
 228
 229        while (!slot->done) {
 230                data_received = 0;
 231                do {
 232                        curlm_result = curl_multi_perform(curlm,
 233                                                          &num_transfers);
 234                } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
 235                if (num_transfers < active_requests) {
 236                        process_curl_messages();
 237                        process_request_queue();
 238                }
 239
 240                if (!data_received && slot->local != NULL) {
 241                        current_pos = ftell(slot->local);
 242                        if (current_pos > last_pos)
 243                                data_received++;
 244                        last_pos = current_pos;
 245                }
 246
 247                if (!slot->done && !data_received) {
 248                        max_fd = 0;
 249                        FD_ZERO(&readfds);
 250                        FD_ZERO(&writefds);
 251                        FD_ZERO(&excfds);
 252                        select_timeout.tv_sec = 0;
 253                        select_timeout.tv_usec = 50000;
 254                        select(max_fd, &readfds, &writefds,
 255                               &excfds, &select_timeout);
 256                }
 257        }
 258}
 259
 260void start_request(struct transfer_request *request)
 261{
 262        char *hex = sha1_to_hex(request->sha1);
 263        char prevfile[PATH_MAX];
 264        char *url;
 265        char *posn;
 266        int prevlocal;
 267        unsigned char prev_buf[PREV_BUF_SIZE];
 268        ssize_t prev_read = 0;
 269        long prev_posn = 0;
 270        char range[RANGE_HEADER_SIZE];
 271        struct curl_slist *range_header = NULL;
 272        struct active_request_slot *slot;
 273
 274        snprintf(prevfile, sizeof(prevfile), "%s.prev", request->filename);
 275        unlink(prevfile);
 276        rename(request->tmpfile, prevfile);
 277        unlink(request->tmpfile);
 278
 279        request->local = open(request->tmpfile,
 280                              O_WRONLY | O_CREAT | O_EXCL, 0666);
 281        if (request->local < 0) {
 282                request->state = ABORTED;
 283                error("Couldn't create temporary file %s for %s: %s\n",
 284                      request->tmpfile, request->filename, strerror(errno));
 285                return;
 286        }
 287
 288        memset(&request->stream, 0, sizeof(request->stream));
 289
 290        inflateInit(&request->stream);
 291
 292        SHA1_Init(&request->c);
 293
 294        url = xmalloc(strlen(request->repo->base) + 50);
 295        request->url = xmalloc(strlen(request->repo->base) + 50);
 296        strcpy(url, request->repo->base);
 297        posn = url + strlen(request->repo->base);
 298        strcpy(posn, "objects/");
 299        posn += 8;
 300        memcpy(posn, hex, 2);
 301        posn += 2;
 302        *(posn++) = '/';
 303        strcpy(posn, hex + 2);
 304        strcpy(request->url, url);
 305
 306        /* If a previous temp file is present, process what was already
 307           fetched. */
 308        prevlocal = open(prevfile, O_RDONLY);
 309        if (prevlocal != -1) {
 310                do {
 311                        prev_read = read(prevlocal, prev_buf, PREV_BUF_SIZE);
 312                        if (prev_read>0) {
 313                                if (fwrite_sha1_file(prev_buf,
 314                                                     1,
 315                                                     prev_read,
 316                                                     request) == prev_read) {
 317                                        prev_posn += prev_read;
 318                                } else {
 319                                        prev_read = -1;
 320                                }
 321                        }
 322                } while (prev_read > 0);
 323                close(prevlocal);
 324        }
 325        unlink(prevfile);
 326
 327        /* Reset inflate/SHA1 if there was an error reading the previous temp
 328           file; also rewind to the beginning of the local file. */
 329        if (prev_read == -1) {
 330                memset(&request->stream, 0, sizeof(request->stream));
 331                inflateInit(&request->stream);
 332                SHA1_Init(&request->c);
 333                if (prev_posn>0) {
 334                        prev_posn = 0;
 335                        lseek(request->local, SEEK_SET, 0);
 336                        ftruncate(request->local, 0);
 337                }
 338        }
 339
 340        slot = get_active_slot();
 341        curl_easy_setopt(slot->curl, CURLOPT_FILE, request);
 342        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
 343        curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, request->errorstr);
 344        curl_easy_setopt(slot->curl, CURLOPT_URL, url);
 345
 346        /* If we have successfully processed data from a previous fetch
 347           attempt, only fetch the data we don't already have. */
 348        if (prev_posn>0) {
 349                if (get_verbosely)
 350                        fprintf(stderr,
 351                                "Resuming fetch of object %s at byte %ld\n",
 352                                hex, prev_posn);
 353                sprintf(range, "Range: bytes=%ld-", prev_posn);
 354                range_header = curl_slist_append(range_header, range);
 355                curl_easy_setopt(slot->curl,
 356                                 CURLOPT_HTTPHEADER, range_header);
 357        }
 358
 359        /* Try to add to multi handle, abort the request on error */
 360        if (!start_active_slot(slot)) {
 361                request->state = ABORTED;
 362                close(request->local);
 363                free(request->url);
 364                return;
 365        }
 366        
 367        request->slot = slot;
 368        request->state = ACTIVE;
 369}
 370
 371void finish_request(struct transfer_request *request)
 372{
 373        fchmod(request->local, 0444);
 374        close(request->local);
 375
 376        if (request->http_code == 416) {
 377                fprintf(stderr, "Warning: requested range invalid; we may already have all the data.\n");
 378        } else if (request->curl_result != CURLE_OK) {
 379                return;
 380        }
 381
 382        inflateEnd(&request->stream);
 383        SHA1_Final(request->real_sha1, &request->c);
 384        if (request->zret != Z_STREAM_END) {
 385                unlink(request->tmpfile);
 386                return;
 387        }
 388        if (memcmp(request->sha1, request->real_sha1, 20)) {
 389                unlink(request->tmpfile);
 390                return;
 391        }
 392        request->rename =
 393                relink_or_rename(request->tmpfile, request->filename);
 394
 395        if (request->rename == 0)
 396                pull_say("got %s\n", sha1_to_hex(request->sha1));
 397}
 398
 399void release_request(struct transfer_request *request)
 400{
 401        struct transfer_request *entry = request_queue_head;
 402
 403        if (request == request_queue_head) {
 404                request_queue_head = request->next;
 405        } else {
 406                while (entry->next != NULL && entry->next != request)
 407                        entry = entry->next;
 408                if (entry->next == request)
 409                        entry->next = entry->next->next;
 410        }
 411
 412        free(request->url);
 413        free(request);
 414}
 415
 416void process_curl_messages()
 417{
 418        int num_messages;
 419        struct active_request_slot *slot;
 420        struct transfer_request *request = NULL;
 421        CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
 422
 423        while (curl_message != NULL) {
 424                if (curl_message->msg == CURLMSG_DONE) {
 425                        slot = active_queue_head;
 426                        while (slot != NULL &&
 427                               slot->curl != curl_message->easy_handle)
 428                                slot = slot->next;
 429                        if (slot != NULL) {
 430                                curl_multi_remove_handle(curlm, slot->curl);
 431                                active_requests--;
 432                                slot->done = 1;
 433                                slot->in_use = 0;
 434                                slot->curl_result = curl_message->data.result;
 435                                request = request_queue_head;
 436                                while (request != NULL &&
 437                                       request->slot != slot)
 438                                        request = request->next;
 439                        } else {
 440                                fprintf(stderr, "Received DONE message for unknown request!\n");
 441                        }
 442                        if (request != NULL) {
 443                                request->curl_result =
 444                                        curl_message->data.result;
 445                                curl_easy_getinfo(slot->curl,
 446                                                  CURLINFO_HTTP_CODE,
 447                                                  &request->http_code);
 448                                request->slot = NULL;
 449
 450                                /* Use alternates if necessary */
 451                                if (request->http_code == 404 &&
 452                                    request->repo->next != NULL) {
 453                                        request->repo = request->repo->next;
 454                                        start_request(request);
 455                                } else {
 456                                        finish_request(request);
 457                                        request->state = COMPLETE;
 458                                }
 459                        }
 460                } else {
 461                        fprintf(stderr, "Unknown CURL message received: %d\n",
 462                                (int)curl_message->msg);
 463                }
 464                curl_message = curl_multi_info_read(curlm, &num_messages);
 465        }
 466}
 467
 468void process_request_queue()
 469{
 470        struct transfer_request *request = request_queue_head;
 471        int num_transfers;
 472
 473        while (active_requests < max_requests && request != NULL) {
 474                if (request->state == WAITING) {
 475                        start_request(request);
 476                        curl_multi_perform(curlm, &num_transfers);
 477                }
 478                request = request->next;
 479        }
 480}
 481
 482void prefetch(unsigned char *sha1)
 483{
 484        struct transfer_request *newreq;
 485        struct transfer_request *tail;
 486        char *filename = sha1_file_name(sha1);
 487
 488        newreq = xmalloc(sizeof(*newreq));
 489        memcpy(newreq->sha1, sha1, 20);
 490        newreq->repo = alt;
 491        newreq->url = NULL;
 492        newreq->local = -1;
 493        newreq->state = WAITING;
 494        snprintf(newreq->filename, sizeof(newreq->filename), "%s", filename);
 495        snprintf(newreq->tmpfile, sizeof(newreq->tmpfile),
 496                 "%s.temp", filename);
 497        newreq->next = NULL;
 498
 499        if (request_queue_head == NULL) {
 500                request_queue_head = newreq;
 501        } else {
 502                tail = request_queue_head;
 503                while (tail->next != NULL) {
 504                        tail = tail->next;
 505                }
 506                tail->next = newreq;
 507        }
 508        process_request_queue();
 509        process_curl_messages();
 510}
 511
 512static int got_alternates = 0;
 513
 514static int fetch_index(struct alt_base *repo, unsigned char *sha1)
 515{
 516        char *hex = sha1_to_hex(sha1);
 517        char *filename;
 518        char *url;
 519        char tmpfile[PATH_MAX];
 520        int ret;
 521        long prev_posn = 0;
 522        char range[RANGE_HEADER_SIZE];
 523        struct curl_slist *range_header = NULL;
 524
 525        FILE *indexfile;
 526        struct active_request_slot *slot;
 527
 528        if (has_pack_index(sha1))
 529                return 0;
 530
 531        if (get_verbosely)
 532                fprintf(stderr, "Getting index for pack %s\n", hex);
 533        
 534        url = xmalloc(strlen(repo->base) + 64);
 535        sprintf(url, "%s/objects/pack/pack-%s.idx", repo->base, hex);
 536        
 537        filename = sha1_pack_index_name(sha1);
 538        snprintf(tmpfile, sizeof(tmpfile), "%s.temp", filename);
 539        indexfile = fopen(tmpfile, "a");
 540        if (!indexfile)
 541                return error("Unable to open local file %s for pack index",
 542                             filename);
 543
 544        slot = get_active_slot();
 545        curl_easy_setopt(slot->curl, CURLOPT_FILE, indexfile);
 546        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
 547        curl_easy_setopt(slot->curl, CURLOPT_URL, url);
 548        slot->local = indexfile;
 549
 550        /* If there is data present from a previous transfer attempt,
 551           resume where it left off */
 552        prev_posn = ftell(indexfile);
 553        if (prev_posn>0) {
 554                if (get_verbosely)
 555                        fprintf(stderr,
 556                                "Resuming fetch of index for pack %s at byte %ld\n",
 557                                hex, prev_posn);
 558                sprintf(range, "Range: bytes=%ld-", prev_posn);
 559                range_header = curl_slist_append(range_header, range);
 560                curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, range_header);
 561        }
 562
 563        if (start_active_slot(slot)) {
 564                run_active_slot(slot);
 565                if (slot->curl_result != CURLE_OK) {
 566                        fclose(indexfile);
 567                        return error("Unable to get pack index %s\n%s", url,
 568                                     curl_errorstr);
 569                }
 570        } else {
 571                return error("Unable to start request");
 572        }
 573
 574        fclose(indexfile);
 575
 576        ret = relink_or_rename(tmpfile, filename);
 577        if (ret)
 578                return error("unable to write index filename %s: %s",
 579                             filename, strerror(ret));
 580
 581        return 0;
 582}
 583
 584static int setup_index(struct alt_base *repo, unsigned char *sha1)
 585{
 586        struct packed_git *new_pack;
 587        if (has_pack_file(sha1))
 588                return 0; // don't list this as something we can get
 589
 590        if (fetch_index(repo, sha1))
 591                return -1;
 592
 593        new_pack = parse_pack_index(sha1);
 594        new_pack->next = repo->packs;
 595        repo->packs = new_pack;
 596        return 0;
 597}
 598
 599static int fetch_alternates(char *base)
 600{
 601        int ret = 0;
 602        struct buffer buffer;
 603        char *url;
 604        char *data;
 605        int i = 0;
 606        int http_specific = 1;
 607        struct alt_base *tail = alt;
 608
 609        struct active_request_slot *slot;
 610        if (got_alternates)
 611                return 0;
 612        data = xmalloc(4096);
 613        buffer.size = 4095;
 614        buffer.posn = 0;
 615        buffer.buffer = data;
 616
 617        if (get_verbosely)
 618                fprintf(stderr, "Getting alternates list\n");
 619        
 620        url = xmalloc(strlen(base) + 31);
 621        sprintf(url, "%s/objects/info/http-alternates", base);
 622
 623        slot = get_active_slot();
 624        curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
 625        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
 626        curl_easy_setopt(slot->curl, CURLOPT_URL, url);
 627        if (start_active_slot(slot)) {
 628                run_active_slot(slot);
 629                if (slot->curl_result != CURLE_OK || !buffer.posn) {
 630                        http_specific = 0;
 631
 632                        sprintf(url, "%s/objects/info/alternates", base);
 633
 634                        slot = get_active_slot();
 635                        curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
 636                        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
 637                                         fwrite_buffer);
 638                        curl_easy_setopt(slot->curl, CURLOPT_URL, url);
 639                        if (start_active_slot(slot)) {
 640                                run_active_slot(slot);
 641                                if (slot->curl_result != CURLE_OK) {
 642                                        return 0;
 643                                }
 644                        }
 645                }
 646        } else {
 647                return 0;
 648        }
 649
 650        data[buffer.posn] = '\0';
 651
 652        while (i < buffer.posn) {
 653                int posn = i;
 654                while (posn < buffer.posn && data[posn] != '\n')
 655                        posn++;
 656                if (data[posn] == '\n') {
 657                        int okay = 0;
 658                        int serverlen = 0;
 659                        struct alt_base *newalt;
 660                        char *target = NULL;
 661                        if (data[i] == '/') {
 662                                serverlen = strchr(base + 8, '/') - base;
 663                                okay = 1;
 664                        } else if (!memcmp(data + i, "../", 3)) {
 665                                i += 3;
 666                                serverlen = strlen(base);
 667                                while (i + 2 < posn && 
 668                                       !memcmp(data + i, "../", 3)) {
 669                                        do {
 670                                                serverlen--;
 671                                        } while (serverlen &&
 672                                                 base[serverlen - 1] != '/');
 673                                        i += 3;
 674                                }
 675                                // If the server got removed, give up.
 676                                okay = strchr(base, ':') - base + 3 < 
 677                                        serverlen;
 678                        } else if (http_specific) {
 679                                char *colon = strchr(data + i, ':');
 680                                char *slash = strchr(data + i, '/');
 681                                if (colon && slash && colon < data + posn &&
 682                                    slash < data + posn && colon < slash) {
 683                                        okay = 1;
 684                                }
 685                        }
 686                        // skip 'objects' at end
 687                        if (okay) {
 688                                target = xmalloc(serverlen + posn - i - 6);
 689                                strncpy(target, base, serverlen);
 690                                strncpy(target + serverlen, data + i,
 691                                        posn - i - 7);
 692                                target[serverlen + posn - i - 7] = '\0';
 693                                if (get_verbosely)
 694                                        fprintf(stderr, 
 695                                                "Also look at %s\n", target);
 696                                newalt = xmalloc(sizeof(*newalt));
 697                                newalt->next = NULL;
 698                                newalt->base = target;
 699                                newalt->got_indices = 0;
 700                                newalt->packs = NULL;
 701                                while (tail->next != NULL)
 702                                        tail = tail->next;
 703                                tail->next = newalt;
 704                                ret++;
 705                        }
 706                }
 707                i = posn + 1;
 708        }
 709        got_alternates = 1;
 710        
 711        return ret;
 712}
 713
 714static int fetch_indices(struct alt_base *repo)
 715{
 716        unsigned char sha1[20];
 717        char *url;
 718        struct buffer buffer;
 719        char *data;
 720        int i = 0;
 721
 722        struct active_request_slot *slot;
 723
 724        if (repo->got_indices)
 725                return 0;
 726
 727        data = xmalloc(4096);
 728        buffer.size = 4096;
 729        buffer.posn = 0;
 730        buffer.buffer = data;
 731
 732        if (get_verbosely)
 733                fprintf(stderr, "Getting pack list\n");
 734        
 735        url = xmalloc(strlen(repo->base) + 21);
 736        sprintf(url, "%s/objects/info/packs", repo->base);
 737
 738        slot = get_active_slot();
 739        curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
 740        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
 741        curl_easy_setopt(slot->curl, CURLOPT_URL, url);
 742        curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, NULL);
 743        if (start_active_slot(slot)) {
 744                run_active_slot(slot);
 745                if (slot->curl_result != CURLE_OK)
 746                        return error("%s", curl_errorstr);
 747        } else {
 748                return error("Unable to start request");
 749        }
 750
 751        while (i < buffer.posn) {
 752                switch (data[i]) {
 753                case 'P':
 754                        i++;
 755                        if (i + 52 < buffer.posn &&
 756                            !strncmp(data + i, " pack-", 6) &&
 757                            !strncmp(data + i + 46, ".pack\n", 6)) {
 758                                get_sha1_hex(data + i + 6, sha1);
 759                                setup_index(repo, sha1);
 760                                i += 51;
 761                                break;
 762                        }
 763                default:
 764                        while (data[i] != '\n')
 765                                i++;
 766                }
 767                i++;
 768        }
 769
 770        repo->got_indices = 1;
 771        return 0;
 772}
 773
 774static int fetch_pack(struct alt_base *repo, unsigned char *sha1)
 775{
 776        char *url;
 777        struct packed_git *target;
 778        struct packed_git **lst;
 779        FILE *packfile;
 780        char *filename;
 781        char tmpfile[PATH_MAX];
 782        int ret;
 783        long prev_posn = 0;
 784        char range[RANGE_HEADER_SIZE];
 785        struct curl_slist *range_header = NULL;
 786
 787        struct active_request_slot *slot;
 788
 789        if (fetch_indices(repo))
 790                return -1;
 791        target = find_sha1_pack(sha1, repo->packs);
 792        if (!target)
 793                return -1;
 794
 795        if (get_verbosely) {
 796                fprintf(stderr, "Getting pack %s\n",
 797                        sha1_to_hex(target->sha1));
 798                fprintf(stderr, " which contains %s\n",
 799                        sha1_to_hex(sha1));
 800        }
 801
 802        url = xmalloc(strlen(repo->base) + 65);
 803        sprintf(url, "%s/objects/pack/pack-%s.pack",
 804                repo->base, sha1_to_hex(target->sha1));
 805
 806        filename = sha1_pack_name(target->sha1);
 807        snprintf(tmpfile, sizeof(tmpfile), "%s.temp", filename);
 808        packfile = fopen(tmpfile, "a");
 809        if (!packfile)
 810                return error("Unable to open local file %s for pack",
 811                             filename);
 812
 813        slot = get_active_slot();
 814        curl_easy_setopt(slot->curl, CURLOPT_FILE, packfile);
 815        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
 816        curl_easy_setopt(slot->curl, CURLOPT_URL, url);
 817        slot->local = packfile;
 818
 819        /* If there is data present from a previous transfer attempt,
 820           resume where it left off */
 821        prev_posn = ftell(packfile);
 822        if (prev_posn>0) {
 823                if (get_verbosely)
 824                        fprintf(stderr,
 825                                "Resuming fetch of pack %s at byte %ld\n",
 826                                sha1_to_hex(target->sha1), prev_posn);
 827                sprintf(range, "Range: bytes=%ld-", prev_posn);
 828                range_header = curl_slist_append(range_header, range);
 829                curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, range_header);
 830        }
 831
 832        if (start_active_slot(slot)) {
 833                run_active_slot(slot);
 834                if (slot->curl_result != CURLE_OK) {
 835                        fclose(packfile);
 836                        return error("Unable to get pack file %s\n%s", url,
 837                                     curl_errorstr);
 838                }
 839        } else {
 840                return error("Unable to start request");
 841        }
 842
 843        fclose(packfile);
 844
 845        ret = relink_or_rename(tmpfile, filename);
 846        if (ret)
 847                return error("unable to write pack filename %s: %s",
 848                             filename, strerror(ret));
 849
 850        lst = &repo->packs;
 851        while (*lst != target)
 852                lst = &((*lst)->next);
 853        *lst = (*lst)->next;
 854
 855        if (verify_pack(target, 0))
 856                return -1;
 857        install_packed_git(target);
 858
 859        return 0;
 860}
 861
 862static int fetch_object(struct alt_base *repo, unsigned char *sha1)
 863{
 864        char *hex = sha1_to_hex(sha1);
 865        int ret;
 866        struct transfer_request *request = request_queue_head;
 867        int num_transfers;
 868
 869        while (request != NULL && memcmp(request->sha1, sha1, 20))
 870                request = request->next;
 871        if (request == NULL)
 872                return error("Couldn't find request for %s in the queue", hex);
 873
 874        while (request->state == WAITING) {
 875                curl_multi_perform(curlm, &num_transfers);
 876                if (num_transfers < active_requests) {
 877                        process_curl_messages();
 878                        process_request_queue();
 879                }
 880        }
 881
 882        if (request->state == ACTIVE)
 883                run_active_slot(request->slot);
 884
 885        if (request->state == ABORTED) {
 886                release_request(request);
 887                return error("Request for %s aborted", hex);
 888        }
 889
 890        if (request->curl_result != CURLE_OK && request->http_code != 416) {
 891                ret = error("%s", request->errorstr);
 892                release_request(request);
 893                return ret;
 894        }
 895
 896        if (request->zret != Z_STREAM_END) {
 897                ret = error("File %s (%s) corrupt\n", hex, request->url);
 898                release_request(request);
 899                return ret;
 900        }
 901
 902        if (memcmp(request->sha1, request->real_sha1, 20)) {
 903                release_request(request);
 904                return error("File %s has bad hash\n", hex);
 905        }
 906
 907        if (request->rename < 0) {
 908                ret = error("unable to write sha1 filename %s: %s",
 909                            request->filename,
 910                            strerror(request->rename));
 911                release_request(request);
 912                return ret;
 913        }
 914
 915        release_request(request);
 916        return 0;
 917}
 918
 919int fetch(unsigned char *sha1)
 920{
 921        struct alt_base *altbase = alt;
 922
 923        if (!fetch_object(altbase, sha1))
 924                return 0;
 925        while (altbase) {
 926                if (!fetch_pack(altbase, sha1))
 927                        return 0;
 928                altbase = altbase->next;
 929        }
 930        return error("Unable to find %s under %s\n", sha1_to_hex(sha1), 
 931                     alt->base);
 932}
 933
 934int fetch_ref(char *ref, unsigned char *sha1)
 935{
 936        char *url, *posn;
 937        char hex[42];
 938        struct buffer buffer;
 939        char *base = alt->base;
 940        struct active_request_slot *slot;
 941        buffer.size = 41;
 942        buffer.posn = 0;
 943        buffer.buffer = hex;
 944        hex[41] = '\0';
 945        
 946        url = xmalloc(strlen(base) + 6 + strlen(ref));
 947        strcpy(url, base);
 948        posn = url + strlen(base);
 949        strcpy(posn, "refs/");
 950        posn += 5;
 951        strcpy(posn, ref);
 952
 953        slot = get_active_slot();
 954        curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
 955        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
 956        curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, NULL);
 957        curl_easy_setopt(slot->curl, CURLOPT_URL, url);
 958        if (start_active_slot(slot)) {
 959                run_active_slot(slot);
 960                if (slot->curl_result != CURLE_OK)
 961                        return error("Couldn't get %s for %s\n%s",
 962                                     url, ref, curl_errorstr);
 963        } else {
 964                return error("Unable to start request");
 965        }
 966
 967        hex[40] = '\0';
 968        get_sha1_hex(hex, sha1);
 969        return 0;
 970}
 971
 972int main(int argc, char **argv)
 973{
 974        char *commit_id;
 975        char *url;
 976        int arg = 1;
 977        struct active_request_slot *slot;
 978
 979        while (arg < argc && argv[arg][0] == '-') {
 980                if (argv[arg][1] == 't') {
 981                        get_tree = 1;
 982                } else if (argv[arg][1] == 'c') {
 983                        get_history = 1;
 984                } else if (argv[arg][1] == 'a') {
 985                        get_all = 1;
 986                        get_tree = 1;
 987                        get_history = 1;
 988                } else if (argv[arg][1] == 'v') {
 989                        get_verbosely = 1;
 990                } else if (argv[arg][1] == 'w') {
 991                        write_ref = argv[arg + 1];
 992                        arg++;
 993                } else if (!strcmp(argv[arg], "--recover")) {
 994                        get_recover = 1;
 995                } else if (argv[arg][1] == 'r') {
 996                        max_requests = atoi(argv[arg + 1]);
 997                        if (max_requests < 1)
 998                                max_requests = DEFAULT_MAX_REQUESTS;
 999                        arg++;
1000                }
1001                arg++;
1002        }
1003        if (argc < arg + 2) {
1004                usage("git-http-fetch [-c] [-t] [-a] [-d] [-v] [--recover] [-w ref] commit-id url");
1005                return 1;
1006        }
1007        commit_id = argv[arg];
1008        url = argv[arg + 1];
1009
1010        curl_global_init(CURL_GLOBAL_ALL);
1011
1012        curlm = curl_multi_init();
1013        if (curlm == NULL) {
1014                fprintf(stderr, "Error creating curl multi handle.\n");
1015                return 1;
1016        }
1017        no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
1018        no_range_header = curl_slist_append(no_range_header, "Range:");
1019
1020        curl_default = curl_easy_init();
1021
1022        curl_ssl_verify = getenv("GIT_SSL_NO_VERIFY") ? 0 : 1;
1023        curl_easy_setopt(curl_default, CURLOPT_SSL_VERIFYPEER, curl_ssl_verify);
1024#if LIBCURL_VERSION_NUM >= 0x070907
1025        curl_easy_setopt(curl_default, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
1026#endif
1027
1028        if ((ssl_cert = getenv("GIT_SSL_CERT")) != NULL) {
1029                curl_easy_setopt(curl_default, CURLOPT_SSLCERT, ssl_cert);
1030        }
1031#if LIBCURL_VERSION_NUM >= 0x070902
1032        if ((ssl_key = getenv("GIT_SSL_KEY")) != NULL) {
1033                curl_easy_setopt(curl_default, CURLOPT_SSLKEY, ssl_key);
1034        }
1035#endif
1036#if LIBCURL_VERSION_NUM >= 0x070908
1037        if ((ssl_capath = getenv("GIT_SSL_CAPATH")) != NULL) {
1038                curl_easy_setopt(curl_default, CURLOPT_CAPATH, ssl_capath);
1039        }
1040#endif
1041        if ((ssl_cainfo = getenv("GIT_SSL_CAINFO")) != NULL) {
1042                curl_easy_setopt(curl_default, CURLOPT_CAINFO, ssl_cainfo);
1043        }
1044        curl_easy_setopt(curl_default, CURLOPT_FAILONERROR, 1);
1045
1046        alt = xmalloc(sizeof(*alt));
1047        alt->base = url;
1048        alt->got_indices = 0;
1049        alt->packs = NULL;
1050        alt->next = NULL;
1051        fetch_alternates(alt->base);
1052
1053        if (pull(commit_id))
1054                return 1;
1055
1056        curl_slist_free_all(no_pragma_header);
1057        curl_slist_free_all(no_range_header);
1058        curl_easy_cleanup(curl_default);
1059        slot = active_queue_head;
1060        while (slot != NULL) {
1061                curl_easy_cleanup(slot->curl);
1062                slot = slot->next;
1063        }
1064        curl_multi_cleanup(curlm);
1065        curl_global_cleanup();
1066        return 0;
1067}