remote-curl.c

   1 #include "cache.h"
   2 #include "remote.h"
   3 #include "strbuf.h"
   4 #include "walker.h"
   5 #include "http.h"
   6 #include "exec_cmd.h"
   7 #include "run-command.h"
   8 #include "pkt-line.h"
   9 #include "sideband.h"
  10
  11 static struct remote *remote;
  12 static const char *url; /* always ends with a trailing slash */
  13
  14 struct options {
  15         int verbosity;
  16         unsigned long depth;
  17         unsigned progress : 1,
  18                 followtags : 1,
  19                 dry_run : 1,
  20                 thin : 1;
  21 };
  22 static struct options options;
  23
  24 static int set_option(const char *name, const char *value)
  25 {
  26         if (!strcmp(name, "verbosity")) {
  27                 char *end;
  28                 int v = strtol(value, &end, 10);
  29                 if (value == end || *end)
  30                         return -1;
  31                 options.verbosity = v;
  32                 return 0;
  33         }
  34         else if (!strcmp(name, "progress")) {
  35                 if (!strcmp(value, "true"))
  36                         options.progress = 1;
  37                 else if (!strcmp(value, "false"))
  38                         options.progress = 0;
  39                 else
  40                         return -1;
  41                 return 0;
  42         }
  43         else if (!strcmp(name, "depth")) {
  44                 char *end;
  45                 unsigned long v = strtoul(value, &end, 10);
  46                 if (value == end || *end)
  47                         return -1;
  48                 options.depth = v;
  49                 return 0;
  50         }
  51         else if (!strcmp(name, "followtags")) {
  52                 if (!strcmp(value, "true"))
  53                         options.followtags = 1;
  54                 else if (!strcmp(value, "false"))
  55                         options.followtags = 0;
  56                 else
  57                         return -1;
  58                 return 0;
  59         }
  60         else if (!strcmp(name, "dry-run")) {
  61                 if (!strcmp(value, "true"))
  62                         options.dry_run = 1;
  63                 else if (!strcmp(value, "false"))
  64                         options.dry_run = 0;
  65                 else
  66                         return -1;
  67                 return 0;
  68         }
  69         else {
  70                 return 1 /* unsupported */;
  71         }
  72 }
  73
  74 struct discovery {
  75         const char *service;
  76         char *buf_alloc;
  77         char *buf;
  78         size_t len;
  79         unsigned proto_git : 1;
  80 };
  81 static struct discovery *last_discovery;
  82
  83 static void free_discovery(struct discovery *d)
  84 {
  85         if (d) {
  86                 if (d == last_discovery)
  87                         last_discovery = NULL;
  88                 free(d->buf_alloc);
  89                 free(d);
  90         }
  91 }
  92
  93 static struct discovery* discover_refs(const char *service)
  94 {
  95         struct strbuf buffer = STRBUF_INIT;
  96         struct discovery *last = last_discovery;
  97         char *refs_url;
  98         int http_ret, is_http = 0, proto_git_candidate = 1;
  99
 100         if (last && !strcmp(service, last->service))
 101                 return last;
 102         free_discovery(last);
 103
 104         strbuf_addf(&buffer, "%sinfo/refs", url);
 105         if (!prefixcmp(url, "http://") || !prefixcmp(url, "https://")) {
 106                 is_http = 1;
 107                 if (!strchr(url, '?'))
 108                         strbuf_addch(&buffer, '?');
 109                 else
 110                         strbuf_addch(&buffer, '&');
 111                 strbuf_addf(&buffer, "service=%s", service);
 112         }
 113         refs_url = strbuf_detach(&buffer, NULL);
 114
 115         http_ret = http_get_strbuf(refs_url, &buffer, HTTP_NO_CACHE);
 116
 117         /* try again with "plain" url (no ? or & appended) */
 118         if (http_ret != HTTP_OK) {
 119                 free(refs_url);
 120                 strbuf_reset(&buffer);
 121
 122                 proto_git_candidate = 0;
 123                 strbuf_addf(&buffer, "%sinfo/refs", url);
 124                 refs_url = strbuf_detach(&buffer, NULL);
 125
 126                 http_ret = http_get_strbuf(refs_url, &buffer, HTTP_NO_CACHE);
 127         }
 128
 129         switch (http_ret) {
 130         case HTTP_OK:
 131                 break;
 132         case HTTP_MISSING_TARGET:
 133                 die("%s not found: did you run git update-server-info on the"
 134                     " server?", refs_url);
 135         case HTTP_NOAUTH:
 136                 die("Authentication failed");
 137         default:
 138                 http_error(refs_url, http_ret);
 139                 die("HTTP request failed");
 140         }
 141
 142         last= xcalloc(1, sizeof(*last_discovery));
 143         last->service = service;
 144         last->buf_alloc = strbuf_detach(&buffer, &last->len);
 145         last->buf = last->buf_alloc;
 146
 147         if (is_http && proto_git_candidate
 148                 && 5 <= last->len && last->buf[4] == '#') {
 149                 /* smart HTTP response; validate that the service
 150                  * pkt-line matches our request.
 151                  */
 152                 struct strbuf exp = STRBUF_INIT;
 153
 154                 if (packet_get_line(&buffer, &last->buf, &last->len) <= 0)
 155                         die("%s has invalid packet header", refs_url);
 156                 if (buffer.len && buffer.buf[buffer.len - 1] == '\n')
 157                         strbuf_setlen(&buffer, buffer.len - 1);
 158
 159                 strbuf_addf(&exp, "# service=%s", service);
 160                 if (strbuf_cmp(&exp, &buffer))
 161                         die("invalid server response; got '%s'", buffer.buf);
 162                 strbuf_release(&exp);
 163
 164                 /* The header can include additional metadata lines, up
 165                  * until a packet flush marker.  Ignore these now, but
 166                  * in the future we might start to scan them.
 167                  */
 168                 strbuf_reset(&buffer);
 169                 while (packet_get_line(&buffer, &last->buf, &last->len) > 0)
 170                         strbuf_reset(&buffer);
 171
 172                 last->proto_git = 1;
 173         }
 174
 175         free(refs_url);
 176         strbuf_release(&buffer);
 177         last_discovery = last;
 178         return last;
 179 }
 180
 181 static int write_discovery(int in, int out, void *data)
 182 {
 183         struct discovery *heads = data;
 184         int err = 0;
 185         if (write_in_full(out, heads->buf, heads->len) != heads->len)
 186                 err = 1;
 187         close(out);
 188         return err;
 189 }
 190
 191 static struct ref *parse_git_refs(struct discovery *heads)
 192 {
 193         struct ref *list = NULL;
 194         struct async async;
 195
 196         memset(&async, 0, sizeof(async));
 197         async.proc = write_discovery;
 198         async.data = heads;
 199         async.out = -1;
 200
 201         if (start_async(&async))
 202                 die("cannot start thread to parse advertised refs");
 203         get_remote_heads(async.out, &list, 0, NULL, 0, NULL);
 204         close(async.out);
 205         if (finish_async(&async))
 206                 die("ref parsing thread failed");
 207         return list;
 208 }
 209
 210 static struct ref *parse_info_refs(struct discovery *heads)
 211 {
 212         char *data, *start, *mid;
 213         char *ref_name;
 214         int i = 0;
 215
 216         struct ref *refs = NULL;
 217         struct ref *ref = NULL;
 218         struct ref *last_ref = NULL;
 219
 220         data = heads->buf;
 221         start = NULL;
 222         mid = data;
 223         while (i < heads->len) {
 224                 if (!start) {
 225                         start = &data[i];
 226                 }
 227                 if (data[i] == '\t')
 228                         mid = &data[i];
 229                 if (data[i] == '\n') {
 230                         if (mid - start != 40)
 231                                 die("%sinfo/refs not valid: is this a git repository?", url);
 232                         data[i] = 0;
 233                         ref_name = mid + 1;
 234                         ref = xmalloc(sizeof(struct ref) +
 235                                       strlen(ref_name) + 1);
 236                         memset(ref, 0, sizeof(struct ref));
 237                         strcpy(ref->name, ref_name);
 238                         get_sha1_hex(start, ref->old_sha1);
 239                         if (!refs)
 240                                 refs = ref;
 241                         if (last_ref)
 242                                 last_ref->next = ref;
 243                         last_ref = ref;
 244                         start = NULL;
 245                 }
 246                 i++;
 247         }
 248
 249         ref = alloc_ref("HEAD");
 250         if (!http_fetch_ref(url, ref) &&
 251             !resolve_remote_symref(ref, refs)) {
 252                 ref->next = refs;
 253                 refs = ref;
 254         } else {
 255                 free(ref);
 256         }
 257
 258         return refs;
 259 }
 260
 261 static struct ref *get_refs(int for_push)
 262 {
 263         struct discovery *heads;
 264
 265         if (for_push)
 266                 heads = discover_refs("git-receive-pack");
 267         else
 268                 heads = discover_refs("git-upload-pack");
 269
 270         if (heads->proto_git)
 271                 return parse_git_refs(heads);
 272         return parse_info_refs(heads);
 273 }
 274
 275 static void output_refs(struct ref *refs)
 276 {
 277         struct ref *posn;
 278         for (posn = refs; posn; posn = posn->next) {
 279                 if (posn->symref)
 280                         printf("@%s %s\n", posn->symref, posn->name);
 281                 else
 282                         printf("%s %s\n", sha1_to_hex(posn->old_sha1), posn->name);
 283         }
 284         printf("\n");
 285         fflush(stdout);
 286         free_refs(refs);
 287 }
 288
 289 struct rpc_state {
 290         const char *service_name;
 291         const char **argv;
 292         char *service_url;
 293         char *hdr_content_type;
 294         char *hdr_accept;
 295         char *buf;
 296         size_t alloc;
 297         size_t len;
 298         size_t pos;
 299         int in;
 300         int out;
 301         struct strbuf result;
 302         unsigned gzip_request : 1;
 303         unsigned initial_buffer : 1;
 304 };
 305
 306 static size_t rpc_out(void *ptr, size_t eltsize,
 307                 size_t nmemb, void *buffer_)
 308 {
 309         size_t max = eltsize * nmemb;
 310         struct rpc_state *rpc = buffer_;
 311         size_t avail = rpc->len - rpc->pos;
 312
 313         if (!avail) {
 314                 rpc->initial_buffer = 0;
 315                 avail = packet_read_line(rpc->out, rpc->buf, rpc->alloc);
 316                 if (!avail)
 317                         return 0;
 318                 rpc->pos = 0;
 319                 rpc->len = avail;
 320         }
 321
 322         if (max < avail)
 323                 avail = max;
 324         memcpy(ptr, rpc->buf + rpc->pos, avail);
 325         rpc->pos += avail;
 326         return avail;
 327 }
 328
 329 #ifndef NO_CURL_IOCTL
 330 static curlioerr rpc_ioctl(CURL *handle, int cmd, void *clientp)
 331 {
 332         struct rpc_state *rpc = clientp;
 333
 334         switch (cmd) {
 335         case CURLIOCMD_NOP:
 336                 return CURLIOE_OK;
 337
 338         case CURLIOCMD_RESTARTREAD:
 339                 if (rpc->initial_buffer) {
 340                         rpc->pos = 0;
 341                         return CURLIOE_OK;
 342                 }
 343                 fprintf(stderr, "Unable to rewind rpc post data - try increasing http.postBuffer\n");
 344                 return CURLIOE_FAILRESTART;
 345
 346         default:
 347                 return CURLIOE_UNKNOWNCMD;
 348         }
 349 }
 350 #endif
 351
 352 static size_t rpc_in(char *ptr, size_t eltsize,
 353                 size_t nmemb, void *buffer_)
 354 {
 355         size_t size = eltsize * nmemb;
 356         struct rpc_state *rpc = buffer_;
 357         write_or_die(rpc->in, ptr, size);
 358         return size;
 359 }
 360
 361 static int run_slot(struct active_request_slot *slot)
 362 {
 363         int err = 0;
 364         struct slot_results results;
 365
 366         slot->results = &results;
 367         slot->curl_result = curl_easy_perform(slot->curl);
 368         finish_active_slot(slot);
 369
 370         if (results.curl_result != CURLE_OK) {
 371                 err |= error("RPC failed; result=%d, HTTP code = %ld",
 372                         results.curl_result, results.http_code);
 373         }
 374
 375         return err;
 376 }
 377
 378 static int probe_rpc(struct rpc_state *rpc)
 379 {
 380         struct active_request_slot *slot;
 381         struct curl_slist *headers = NULL;
 382         struct strbuf buf = STRBUF_INIT;
 383         int err;
 384
 385         slot = get_active_slot();
 386
 387         headers = curl_slist_append(headers, rpc->hdr_content_type);
 388         headers = curl_slist_append(headers, rpc->hdr_accept);
 389
 390         curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
 391         curl_easy_setopt(slot->curl, CURLOPT_POST, 1);
 392         curl_easy_setopt(slot->curl, CURLOPT_URL, rpc->service_url);
 393         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "");
 394         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, "0000");
 395         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDSIZE, 4);
 396         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
 397         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
 398         curl_easy_setopt(slot->curl, CURLOPT_FILE, &buf);
 399
 400         err = run_slot(slot);
 401
 402         curl_slist_free_all(headers);
 403         strbuf_release(&buf);
 404         return err;
 405 }
 406
 407 static int post_rpc(struct rpc_state *rpc)
 408 {
 409         struct active_request_slot *slot;
 410         struct curl_slist *headers = NULL;
 411         int use_gzip = rpc->gzip_request;
 412         char *gzip_body = NULL;
 413         int err, large_request = 0;
 414
 415         /* Try to load the entire request, if we can fit it into the
 416          * allocated buffer space we can use HTTP/1.0 and avoid the
 417          * chunked encoding mess.
 418          */
 419         while (1) {
 420                 size_t left = rpc->alloc - rpc->len;
 421                 char *buf = rpc->buf + rpc->len;
 422                 int n;
 423
 424                 if (left < LARGE_PACKET_MAX) {
 425                         large_request = 1;
 426                         use_gzip = 0;
 427                         break;
 428                 }
 429
 430                 n = packet_read_line(rpc->out, buf, left);
 431                 if (!n)
 432                         break;
 433                 rpc->len += n;
 434         }
 435
 436         if (large_request) {
 437                 err = probe_rpc(rpc);
 438                 if (err)
 439                         return err;
 440         }
 441
 442         slot = get_active_slot();
 443
 444         curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
 445         curl_easy_setopt(slot->curl, CURLOPT_POST, 1);
 446         curl_easy_setopt(slot->curl, CURLOPT_URL, rpc->service_url);
 447         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "");
 448
 449         headers = curl_slist_append(headers, rpc->hdr_content_type);
 450         headers = curl_slist_append(headers, rpc->hdr_accept);
 451         headers = curl_slist_append(headers, "Expect:");
 452
 453         if (large_request) {
 454                 /* The request body is large and the size cannot be predicted.
 455                  * We must use chunked encoding to send it.
 456                  */
 457                 headers = curl_slist_append(headers, "Transfer-Encoding: chunked");
 458                 rpc->initial_buffer = 1;
 459                 curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, rpc_out);
 460                 curl_easy_setopt(slot->curl, CURLOPT_INFILE, rpc);
 461 #ifndef NO_CURL_IOCTL
 462                 curl_easy_setopt(slot->curl, CURLOPT_IOCTLFUNCTION, rpc_ioctl);
 463                 curl_easy_setopt(slot->curl, CURLOPT_IOCTLDATA, rpc);
 464 #endif
 465                 if (options.verbosity > 1) {
 466                         fprintf(stderr, "POST %s (chunked)\n", rpc->service_name);
 467                         fflush(stderr);
 468                 }
 469
 470         } else if (use_gzip && 1024 < rpc->len) {
 471                 /* The client backend isn't giving us compressed data so
 472                  * we can try to deflate it ourselves, this may save on.
 473                  * the transfer time.
 474                  */
 475                 size_t size;
 476                 z_stream stream;
 477                 int ret;
 478
 479                 memset(&stream, 0, sizeof(stream));
 480                 ret = deflateInit2(&stream, Z_BEST_COMPRESSION,
 481                                 Z_DEFLATED, (15 + 16),
 482                                 8, Z_DEFAULT_STRATEGY);
 483                 if (ret != Z_OK)
 484                         die("cannot deflate request; zlib init error %d", ret);
 485                 size = deflateBound(&stream, rpc->len);
 486                 gzip_body = xmalloc(size);
 487
 488                 stream.next_in = (unsigned char *)rpc->buf;
 489                 stream.avail_in = rpc->len;
 490                 stream.next_out = (unsigned char *)gzip_body;
 491                 stream.avail_out = size;
 492
 493                 ret = deflate(&stream, Z_FINISH);
 494                 if (ret != Z_STREAM_END)
 495                         die("cannot deflate request; zlib deflate error %d", ret);
 496
 497                 ret = deflateEnd(&stream);
 498                 if (ret != Z_OK)
 499                         die("cannot deflate request; zlib end error %d", ret);
 500
 501                 size = stream.total_out;
 502
 503                 headers = curl_slist_append(headers, "Content-Encoding: gzip");
 504                 curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, gzip_body);
 505                 curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDSIZE, size);
 506
 507                 if (options.verbosity > 1) {
 508                         fprintf(stderr, "POST %s (gzip %lu to %lu bytes)\n",
 509                                 rpc->service_name,
 510                                 (unsigned long)rpc->len, (unsigned long)size);
 511                         fflush(stderr);
 512                 }
 513         } else {
 514                 /* We know the complete request size in advance, use the
 515                  * more normal Content-Length approach.
 516                  */
 517                 curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, rpc->buf);
 518                 curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDSIZE, rpc->len);
 519                 if (options.verbosity > 1) {
 520                         fprintf(stderr, "POST %s (%lu bytes)\n",
 521                                 rpc->service_name, (unsigned long)rpc->len);
 522                         fflush(stderr);
 523                 }
 524         }
 525
 526         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
 527         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, rpc_in);
 528         curl_easy_setopt(slot->curl, CURLOPT_FILE, rpc);
 529
 530         err = run_slot(slot);
 531
 532         curl_slist_free_all(headers);
 533         free(gzip_body);
 534         return err;
 535 }
 536
 537 static int rpc_service(struct rpc_state *rpc, struct discovery *heads)
 538 {
 539         const char *svc = rpc->service_name;
 540         struct strbuf buf = STRBUF_INIT;
 541         struct child_process client;
 542         int err = 0;
 543
 544         memset(&client, 0, sizeof(client));
 545         client.in = -1;
 546         client.out = -1;
 547         client.git_cmd = 1;
 548         client.argv = rpc->argv;
 549         if (start_command(&client))
 550                 exit(1);
 551         if (heads)
 552                 write_or_die(client.in, heads->buf, heads->len);
 553
 554         rpc->alloc = http_post_buffer;
 555         rpc->buf = xmalloc(rpc->alloc);
 556         rpc->in = client.in;
 557         rpc->out = client.out;
 558         strbuf_init(&rpc->result, 0);
 559
 560         strbuf_addf(&buf, "%s%s", url, svc);
 561         rpc->service_url = strbuf_detach(&buf, NULL);
 562
 563         strbuf_addf(&buf, "Content-Type: application/x-%s-request", svc);
 564         rpc->hdr_content_type = strbuf_detach(&buf, NULL);
 565
 566         strbuf_addf(&buf, "Accept: application/x-%s-result", svc);
 567         rpc->hdr_accept = strbuf_detach(&buf, NULL);
 568
 569         while (!err) {
 570                 int n = packet_read_line(rpc->out, rpc->buf, rpc->alloc);
 571                 if (!n)
 572                         break;
 573                 rpc->pos = 0;
 574                 rpc->len = n;
 575                 err |= post_rpc(rpc);
 576         }
 577
 578         close(client.in);
 579         client.in = -1;
 580         strbuf_read(&rpc->result, client.out, 0);
 581
 582         close(client.out);
 583         client.out = -1;
 584
 585         err |= finish_command(&client);
 586         free(rpc->service_url);
 587         free(rpc->hdr_content_type);
 588         free(rpc->hdr_accept);
 589         free(rpc->buf);
 590         strbuf_release(&buf);
 591         return err;
 592 }
 593
 594 static int fetch_dumb(int nr_heads, struct ref **to_fetch)
 595 {
 596         struct walker *walker;
 597         char **targets = xmalloc(nr_heads * sizeof(char*));
 598         int ret, i;
 599
 600         if (options.depth)
 601                 die("dumb http transport does not support --depth");
 602         for (i = 0; i < nr_heads; i++)
 603                 targets[i] = xstrdup(sha1_to_hex(to_fetch[i]->old_sha1));
 604
 605         walker = get_http_walker(url);
 606         walker->get_all = 1;
 607         walker->get_tree = 1;
 608         walker->get_history = 1;
 609         walker->get_verbosely = options.verbosity >= 3;
 610         walker->get_recover = 0;
 611         ret = walker_fetch(walker, nr_heads, targets, NULL, NULL);
 612         walker_free(walker);
 613
 614         for (i = 0; i < nr_heads; i++)
 615                 free(targets[i]);
 616         free(targets);
 617
 618         return ret ? error("Fetch failed.") : 0;
 619 }
 620
 621 static int fetch_git(struct discovery *heads,
 622         int nr_heads, struct ref **to_fetch)
 623 {
 624         struct rpc_state rpc;
 625         char *depth_arg = NULL;
 626         const char **argv;
 627         int argc = 0, i, err;
 628
 629         argv = xmalloc((15 + nr_heads) * sizeof(char*));
 630         argv[argc++] = "fetch-pack";
 631         argv[argc++] = "--stateless-rpc";
 632         argv[argc++] = "--lock-pack";
 633         if (options.followtags)
 634                 argv[argc++] = "--include-tag";
 635         if (options.thin)
 636                 argv[argc++] = "--thin";
 637         if (options.verbosity >= 3) {
 638                 argv[argc++] = "-v";
 639                 argv[argc++] = "-v";
 640         }
 641         if (!options.progress)
 642                 argv[argc++] = "--no-progress";
 643         if (options.depth) {
 644                 struct strbuf buf = STRBUF_INIT;
 645                 strbuf_addf(&buf, "--depth=%lu", options.depth);
 646                 depth_arg = strbuf_detach(&buf, NULL);
 647                 argv[argc++] = depth_arg;
 648         }
 649         argv[argc++] = url;
 650         for (i = 0; i < nr_heads; i++) {
 651                 struct ref *ref = to_fetch[i];
 652                 if (!ref->name || !*ref->name)
 653                         die("cannot fetch by sha1 over smart http");
 654                 argv[argc++] = ref->name;
 655         }
 656         argv[argc++] = NULL;
 657
 658         memset(&rpc, 0, sizeof(rpc));
 659         rpc.service_name = "git-upload-pack",
 660         rpc.argv = argv;
 661         rpc.gzip_request = 1;
 662
 663         err = rpc_service(&rpc, heads);
 664         if (rpc.result.len)
 665                 safe_write(1, rpc.result.buf, rpc.result.len);
 666         strbuf_release(&rpc.result);
 667         free(argv);
 668         free(depth_arg);
 669         return err;
 670 }
 671
 672 static int fetch(int nr_heads, struct ref **to_fetch)
 673 {
 674         struct discovery *d = discover_refs("git-upload-pack");
 675         if (d->proto_git)
 676                 return fetch_git(d, nr_heads, to_fetch);
 677         else
 678                 return fetch_dumb(nr_heads, to_fetch);
 679 }
 680
 681 static void parse_fetch(struct strbuf *buf)
 682 {
 683         struct ref **to_fetch = NULL;
 684         struct ref *list_head = NULL;
 685         struct ref **list = &list_head;
 686         int alloc_heads = 0, nr_heads = 0;
 687
 688         do {
 689                 if (!prefixcmp(buf->buf, "fetch ")) {
 690                         char *p = buf->buf + strlen("fetch ");
 691                         char *name;
 692                         struct ref *ref;
 693                         unsigned char old_sha1[20];
 694
 695                         if (strlen(p) < 40 || get_sha1_hex(p, old_sha1))
 696                                 die("protocol error: expected sha/ref, got %s'", p);
 697                         if (p[40] == ' ')
 698                                 name = p + 41;
 699                         else if (!p[40])
 700                                 name = "";
 701                         else
 702                                 die("protocol error: expected sha/ref, got %s'", p);
 703
 704                         ref = alloc_ref(name);
 705                         hashcpy(ref->old_sha1, old_sha1);
 706
 707                         *list = ref;
 708                         list = &ref->next;
 709
 710                         ALLOC_GROW(to_fetch, nr_heads + 1, alloc_heads);
 711                         to_fetch[nr_heads++] = ref;
 712                 }
 713                 else
 714                         die("http transport does not support %s", buf->buf);
 715
 716                 strbuf_reset(buf);
 717                 if (strbuf_getline(buf, stdin, '\n') == EOF)
 718                         return;
 719                 if (!*buf->buf)
 720                         break;
 721         } while (1);
 722
 723         if (fetch(nr_heads, to_fetch))
 724                 exit(128); /* error already reported */
 725         free_refs(list_head);
 726         free(to_fetch);
 727
 728         printf("\n");
 729         fflush(stdout);
 730         strbuf_reset(buf);
 731 }
 732
 733 static int push_dav(int nr_spec, char **specs)
 734 {
 735         const char **argv = xmalloc((10 + nr_spec) * sizeof(char*));
 736         int argc = 0, i;
 737
 738         argv[argc++] = "http-push";
 739         argv[argc++] = "--helper-status";
 740         if (options.dry_run)
 741                 argv[argc++] = "--dry-run";
 742         if (options.verbosity > 1)
 743                 argv[argc++] = "--verbose";
 744         argv[argc++] = url;
 745         for (i = 0; i < nr_spec; i++)
 746                 argv[argc++] = specs[i];
 747         argv[argc++] = NULL;
 748
 749         if (run_command_v_opt(argv, RUN_GIT_CMD))
 750                 die("git-%s failed", argv[0]);
 751         free(argv);
 752         return 0;
 753 }
 754
 755 static int push_git(struct discovery *heads, int nr_spec, char **specs)
 756 {
 757         struct rpc_state rpc;
 758         const char **argv;
 759         int argc = 0, i, err;
 760
 761         argv = xmalloc((10 + nr_spec) * sizeof(char*));
 762         argv[argc++] = "send-pack";
 763         argv[argc++] = "--stateless-rpc";
 764         argv[argc++] = "--helper-status";
 765         if (options.thin)
 766                 argv[argc++] = "--thin";
 767         if (options.dry_run)
 768                 argv[argc++] = "--dry-run";
 769         if (options.verbosity > 1)
 770                 argv[argc++] = "--verbose";
 771         argv[argc++] = url;
 772         for (i = 0; i < nr_spec; i++)
 773                 argv[argc++] = specs[i];
 774         argv[argc++] = NULL;
 775
 776         memset(&rpc, 0, sizeof(rpc));
 777         rpc.service_name = "git-receive-pack",
 778         rpc.argv = argv;
 779
 780         err = rpc_service(&rpc, heads);
 781         if (rpc.result.len)
 782                 safe_write(1, rpc.result.buf, rpc.result.len);
 783         strbuf_release(&rpc.result);
 784         free(argv);
 785         return err;
 786 }
 787
 788 static int push(int nr_spec, char **specs)
 789 {
 790         struct discovery *heads = discover_refs("git-receive-pack");
 791         int ret;
 792
 793         if (heads->proto_git)
 794                 ret = push_git(heads, nr_spec, specs);
 795         else
 796                 ret = push_dav(nr_spec, specs);
 797         free_discovery(heads);
 798         return ret;
 799 }
 800
 801 static void parse_push(struct strbuf *buf)
 802 {
 803         char **specs = NULL;
 804         int alloc_spec = 0, nr_spec = 0, i;
 805
 806         do {
 807                 if (!prefixcmp(buf->buf, "push ")) {
 808                         ALLOC_GROW(specs, nr_spec + 1, alloc_spec);
 809                         specs[nr_spec++] = xstrdup(buf->buf + 5);
 810                 }
 811                 else
 812                         die("http transport does not support %s", buf->buf);
 813
 814                 strbuf_reset(buf);
 815                 if (strbuf_getline(buf, stdin, '\n') == EOF)
 816                         goto free_specs;
 817                 if (!*buf->buf)
 818                         break;
 819         } while (1);
 820
 821         if (push(nr_spec, specs))
 822                 exit(128); /* error already reported */
 823
 824         printf("\n");
 825         fflush(stdout);
 826
 827  free_specs:
 828         for (i = 0; i < nr_spec; i++)
 829                 free(specs[i]);
 830         free(specs);
 831 }
 832
 833 int main(int argc, const char **argv)
 834 {
 835         struct strbuf buf = STRBUF_INIT;
 836         int nongit;
 837
 838         git_extract_argv0_path(argv[0]);
 839         setup_git_directory_gently(&nongit);
 840         if (argc < 2) {
 841                 fprintf(stderr, "Remote needed\n");
 842                 return 1;
 843         }
 844
 845         options.verbosity = 1;
 846         options.progress = !!isatty(2);
 847         options.thin = 1;
 848
 849         remote = remote_get(argv[1]);
 850
 851         if (argc > 2) {
 852                 end_url_with_slash(&buf, argv[2]);
 853         } else {
 854                 end_url_with_slash(&buf, remote->url[0]);
 855         }
 856
 857         url = strbuf_detach(&buf, NULL);
 858
 859         http_init(remote);
 860
 861         do {
 862                 if (strbuf_getline(&buf, stdin, '\n') == EOF)
 863                         break;
 864                 if (!prefixcmp(buf.buf, "fetch ")) {
 865                         if (nongit)
 866                                 die("Fetch attempted without a local repo");
 867                         parse_fetch(&buf);
 868
 869                 } else if (!strcmp(buf.buf, "list") || !prefixcmp(buf.buf, "list ")) {
 870                         int for_push = !!strstr(buf.buf + 4, "for-push");
 871                         output_refs(get_refs(for_push));
 872
 873                 } else if (!prefixcmp(buf.buf, "push ")) {
 874                         parse_push(&buf);
 875
 876                 } else if (!prefixcmp(buf.buf, "option ")) {
 877                         char *name = buf.buf + strlen("option ");
 878                         char *value = strchr(name, ' ');
 879                         int result;
 880
 881                         if (value)
 882                                 *value++ = '\0';
 883                         else
 884                                 value = "true";
 885
 886                         result = set_option(name, value);
 887                         if (!result)
 888                                 printf("ok\n");
 889                         else if (result < 0)
 890                                 printf("error invalid value\n");
 891                         else
 892                                 printf("unsupported\n");
 893                         fflush(stdout);
 894
 895                 } else if (!strcmp(buf.buf, "capabilities")) {
 896                         printf("fetch\n");
 897                         printf("option\n");
 898                         printf("push\n");
 899                         printf("\n");
 900                         fflush(stdout);
 901                 } else {
 902                         return 1;
 903                 }
 904                 strbuf_reset(&buf);
 905         } while (1);
 906
 907         http_cleanup();
 908
 909         return 0;
 910 }