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                         data[i] = 0;
 231                         ref_name = mid + 1;
 232                         ref = xmalloc(sizeof(struct ref) +
 233                                       strlen(ref_name) + 1);
 234                         memset(ref, 0, sizeof(struct ref));
 235                         strcpy(ref->name, ref_name);
 236                         get_sha1_hex(start, ref->old_sha1);
 237                         if (!refs)
 238                                 refs = ref;
 239                         if (last_ref)
 240                                 last_ref->next = ref;
 241                         last_ref = ref;
 242                         start = NULL;
 243                 }
 244                 i++;
 245         }
 246
 247         ref = alloc_ref("HEAD");
 248         if (!http_fetch_ref(url, ref) &&
 249             !resolve_remote_symref(ref, refs)) {
 250                 ref->next = refs;
 251                 refs = ref;
 252         } else {
 253                 free(ref);
 254         }
 255
 256         return refs;
 257 }
 258
 259 static struct ref *get_refs(int for_push)
 260 {
 261         struct discovery *heads;
 262
 263         if (for_push)
 264                 heads = discover_refs("git-receive-pack");
 265         else
 266                 heads = discover_refs("git-upload-pack");
 267
 268         if (heads->proto_git)
 269                 return parse_git_refs(heads);
 270         return parse_info_refs(heads);
 271 }
 272
 273 static void output_refs(struct ref *refs)
 274 {
 275         struct ref *posn;
 276         for (posn = refs; posn; posn = posn->next) {
 277                 if (posn->symref)
 278                         printf("@%s %s\n", posn->symref, posn->name);
 279                 else
 280                         printf("%s %s\n", sha1_to_hex(posn->old_sha1), posn->name);
 281         }
 282         printf("\n");
 283         fflush(stdout);
 284         free_refs(refs);
 285 }
 286
 287 struct rpc_state {
 288         const char *service_name;
 289         const char **argv;
 290         char *service_url;
 291         char *hdr_content_type;
 292         char *hdr_accept;
 293         char *buf;
 294         size_t alloc;
 295         size_t len;
 296         size_t pos;
 297         int in;
 298         int out;
 299         struct strbuf result;
 300         unsigned gzip_request : 1;
 301         unsigned initial_buffer : 1;
 302 };
 303
 304 static size_t rpc_out(void *ptr, size_t eltsize,
 305                 size_t nmemb, void *buffer_)
 306 {
 307         size_t max = eltsize * nmemb;
 308         struct rpc_state *rpc = buffer_;
 309         size_t avail = rpc->len - rpc->pos;
 310
 311         if (!avail) {
 312                 rpc->initial_buffer = 0;
 313                 avail = packet_read_line(rpc->out, rpc->buf, rpc->alloc);
 314                 if (!avail)
 315                         return 0;
 316                 rpc->pos = 0;
 317                 rpc->len = avail;
 318         }
 319
 320         if (max < avail)
 321                 avail = max;
 322         memcpy(ptr, rpc->buf + rpc->pos, avail);
 323         rpc->pos += avail;
 324         return avail;
 325 }
 326
 327 #ifndef NO_CURL_IOCTL
 328 static curlioerr rpc_ioctl(CURL *handle, int cmd, void *clientp)
 329 {
 330         struct rpc_state *rpc = clientp;
 331
 332         switch (cmd) {
 333         case CURLIOCMD_NOP:
 334                 return CURLIOE_OK;
 335
 336         case CURLIOCMD_RESTARTREAD:
 337                 if (rpc->initial_buffer) {
 338                         rpc->pos = 0;
 339                         return CURLIOE_OK;
 340                 }
 341                 fprintf(stderr, "Unable to rewind rpc post data - try increasing http.postBuffer\n");
 342                 return CURLIOE_FAILRESTART;
 343
 344         default:
 345                 return CURLIOE_UNKNOWNCMD;
 346         }
 347 }
 348 #endif
 349
 350 static size_t rpc_in(const void *ptr, size_t eltsize,
 351                 size_t nmemb, void *buffer_)
 352 {
 353         size_t size = eltsize * nmemb;
 354         struct rpc_state *rpc = buffer_;
 355         write_or_die(rpc->in, ptr, size);
 356         return size;
 357 }
 358
 359 static int run_slot(struct active_request_slot *slot)
 360 {
 361         int err = 0;
 362         struct slot_results results;
 363
 364         slot->results = &results;
 365         slot->curl_result = curl_easy_perform(slot->curl);
 366         finish_active_slot(slot);
 367
 368         if (results.curl_result != CURLE_OK) {
 369                 err |= error("RPC failed; result=%d, HTTP code = %ld",
 370                         results.curl_result, results.http_code);
 371         }
 372
 373         return err;
 374 }
 375
 376 static int probe_rpc(struct rpc_state *rpc)
 377 {
 378         struct active_request_slot *slot;
 379         struct curl_slist *headers = NULL;
 380         struct strbuf buf = STRBUF_INIT;
 381         int err;
 382
 383         slot = get_active_slot();
 384
 385         headers = curl_slist_append(headers, rpc->hdr_content_type);
 386         headers = curl_slist_append(headers, rpc->hdr_accept);
 387
 388         curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
 389         curl_easy_setopt(slot->curl, CURLOPT_POST, 1);
 390         curl_easy_setopt(slot->curl, CURLOPT_URL, rpc->service_url);
 391         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "");
 392         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, "0000");
 393         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDSIZE, 4);
 394         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
 395         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
 396         curl_easy_setopt(slot->curl, CURLOPT_FILE, &buf);
 397
 398         err = run_slot(slot);
 399
 400         curl_slist_free_all(headers);
 401         strbuf_release(&buf);
 402         return err;
 403 }
 404
 405 static int post_rpc(struct rpc_state *rpc)
 406 {
 407         struct active_request_slot *slot;
 408         struct curl_slist *headers = NULL;
 409         int use_gzip = rpc->gzip_request;
 410         char *gzip_body = NULL;
 411         int err, large_request = 0;
 412
 413         /* Try to load the entire request, if we can fit it into the
 414          * allocated buffer space we can use HTTP/1.0 and avoid the
 415          * chunked encoding mess.
 416          */
 417         while (1) {
 418                 size_t left = rpc->alloc - rpc->len;
 419                 char *buf = rpc->buf + rpc->len;
 420                 int n;
 421
 422                 if (left < LARGE_PACKET_MAX) {
 423                         large_request = 1;
 424                         use_gzip = 0;
 425                         break;
 426                 }
 427
 428                 n = packet_read_line(rpc->out, buf, left);
 429                 if (!n)
 430                         break;
 431                 rpc->len += n;
 432         }
 433
 434         if (large_request) {
 435                 err = probe_rpc(rpc);
 436                 if (err)
 437                         return err;
 438         }
 439
 440         slot = get_active_slot();
 441
 442         curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
 443         curl_easy_setopt(slot->curl, CURLOPT_POST, 1);
 444         curl_easy_setopt(slot->curl, CURLOPT_URL, rpc->service_url);
 445         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "");
 446
 447         headers = curl_slist_append(headers, rpc->hdr_content_type);
 448         headers = curl_slist_append(headers, rpc->hdr_accept);
 449         headers = curl_slist_append(headers, "Expect:");
 450
 451         if (large_request) {
 452                 /* The request body is large and the size cannot be predicted.
 453                  * We must use chunked encoding to send it.
 454                  */
 455                 headers = curl_slist_append(headers, "Transfer-Encoding: chunked");
 456                 rpc->initial_buffer = 1;
 457                 curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, rpc_out);
 458                 curl_easy_setopt(slot->curl, CURLOPT_INFILE, rpc);
 459 #ifndef NO_CURL_IOCTL
 460                 curl_easy_setopt(slot->curl, CURLOPT_IOCTLFUNCTION, rpc_ioctl);
 461                 curl_easy_setopt(slot->curl, CURLOPT_IOCTLDATA, rpc);
 462 #endif
 463                 if (options.verbosity > 1) {
 464                         fprintf(stderr, "POST %s (chunked)\n", rpc->service_name);
 465                         fflush(stderr);
 466                 }
 467
 468         } else if (use_gzip && 1024 < rpc->len) {
 469                 /* The client backend isn't giving us compressed data so
 470                  * we can try to deflate it ourselves, this may save on.
 471                  * the transfer time.
 472                  */
 473                 size_t size;
 474                 z_stream stream;
 475                 int ret;
 476
 477                 memset(&stream, 0, sizeof(stream));
 478                 ret = deflateInit2(&stream, Z_BEST_COMPRESSION,
 479                                 Z_DEFLATED, (15 + 16),
 480                                 8, Z_DEFAULT_STRATEGY);
 481                 if (ret != Z_OK)
 482                         die("cannot deflate request; zlib init error %d", ret);
 483                 size = deflateBound(&stream, rpc->len);
 484                 gzip_body = xmalloc(size);
 485
 486                 stream.next_in = (unsigned char *)rpc->buf;
 487                 stream.avail_in = rpc->len;
 488                 stream.next_out = (unsigned char *)gzip_body;
 489                 stream.avail_out = size;
 490
 491                 ret = deflate(&stream, Z_FINISH);
 492                 if (ret != Z_STREAM_END)
 493                         die("cannot deflate request; zlib deflate error %d", ret);
 494
 495                 ret = deflateEnd(&stream);
 496                 if (ret != Z_OK)
 497                         die("cannot deflate request; zlib end error %d", ret);
 498
 499                 size = stream.total_out;
 500
 501                 headers = curl_slist_append(headers, "Content-Encoding: gzip");
 502                 curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, gzip_body);
 503                 curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDSIZE, size);
 504
 505                 if (options.verbosity > 1) {
 506                         fprintf(stderr, "POST %s (gzip %lu to %lu bytes)\n",
 507                                 rpc->service_name,
 508                                 (unsigned long)rpc->len, (unsigned long)size);
 509                         fflush(stderr);
 510                 }
 511         } else {
 512                 /* We know the complete request size in advance, use the
 513                  * more normal Content-Length approach.
 514                  */
 515                 curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, rpc->buf);
 516                 curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDSIZE, rpc->len);
 517                 if (options.verbosity > 1) {
 518                         fprintf(stderr, "POST %s (%lu bytes)\n",
 519                                 rpc->service_name, (unsigned long)rpc->len);
 520                         fflush(stderr);
 521                 }
 522         }
 523
 524         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
 525         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, rpc_in);
 526         curl_easy_setopt(slot->curl, CURLOPT_FILE, rpc);
 527
 528         err = run_slot(slot);
 529
 530         curl_slist_free_all(headers);
 531         free(gzip_body);
 532         return err;
 533 }
 534
 535 static int rpc_service(struct rpc_state *rpc, struct discovery *heads)
 536 {
 537         const char *svc = rpc->service_name;
 538         struct strbuf buf = STRBUF_INIT;
 539         struct child_process client;
 540         int err = 0;
 541
 542         memset(&client, 0, sizeof(client));
 543         client.in = -1;
 544         client.out = -1;
 545         client.git_cmd = 1;
 546         client.argv = rpc->argv;
 547         if (start_command(&client))
 548                 exit(1);
 549         if (heads)
 550                 write_or_die(client.in, heads->buf, heads->len);
 551
 552         rpc->alloc = http_post_buffer;
 553         rpc->buf = xmalloc(rpc->alloc);
 554         rpc->in = client.in;
 555         rpc->out = client.out;
 556         strbuf_init(&rpc->result, 0);
 557
 558         strbuf_addf(&buf, "%s%s", url, svc);
 559         rpc->service_url = strbuf_detach(&buf, NULL);
 560
 561         strbuf_addf(&buf, "Content-Type: application/x-%s-request", svc);
 562         rpc->hdr_content_type = strbuf_detach(&buf, NULL);
 563
 564         strbuf_addf(&buf, "Accept: application/x-%s-result", svc);
 565         rpc->hdr_accept = strbuf_detach(&buf, NULL);
 566
 567         while (!err) {
 568                 int n = packet_read_line(rpc->out, rpc->buf, rpc->alloc);
 569                 if (!n)
 570                         break;
 571                 rpc->pos = 0;
 572                 rpc->len = n;
 573                 err |= post_rpc(rpc);
 574         }
 575
 576         close(client.in);
 577         client.in = -1;
 578         if (!err) {
 579                 strbuf_read(&rpc->result, client.out, 0);
 580         } else {
 581                 char buf[4096];
 582                 for (;;)
 583                         if (xread(client.out, buf, sizeof(buf)) <= 0)
 584                                 break;
 585         }
 586
 587         close(client.out);
 588         client.out = -1;
 589
 590         err |= finish_command(&client);
 591         free(rpc->service_url);
 592         free(rpc->hdr_content_type);
 593         free(rpc->hdr_accept);
 594         free(rpc->buf);
 595         strbuf_release(&buf);
 596         return err;
 597 }
 598
 599 static int fetch_dumb(int nr_heads, struct ref **to_fetch)
 600 {
 601         struct walker *walker;
 602         char **targets = xmalloc(nr_heads * sizeof(char*));
 603         int ret, i;
 604
 605         if (options.depth)
 606                 die("dumb http transport does not support --depth");
 607         for (i = 0; i < nr_heads; i++)
 608                 targets[i] = xstrdup(sha1_to_hex(to_fetch[i]->old_sha1));
 609
 610         walker = get_http_walker(url);
 611         walker->get_all = 1;
 612         walker->get_tree = 1;
 613         walker->get_history = 1;
 614         walker->get_verbosely = options.verbosity >= 3;
 615         walker->get_recover = 0;
 616         ret = walker_fetch(walker, nr_heads, targets, NULL, NULL);
 617         walker_free(walker);
 618
 619         for (i = 0; i < nr_heads; i++)
 620                 free(targets[i]);
 621         free(targets);
 622
 623         return ret ? error("Fetch failed.") : 0;
 624 }
 625
 626 static int fetch_git(struct discovery *heads,
 627         int nr_heads, struct ref **to_fetch)
 628 {
 629         struct rpc_state rpc;
 630         char *depth_arg = NULL;
 631         const char **argv;
 632         int argc = 0, i, err;
 633
 634         argv = xmalloc((15 + nr_heads) * sizeof(char*));
 635         argv[argc++] = "fetch-pack";
 636         argv[argc++] = "--stateless-rpc";
 637         argv[argc++] = "--lock-pack";
 638         if (options.followtags)
 639                 argv[argc++] = "--include-tag";
 640         if (options.thin)
 641                 argv[argc++] = "--thin";
 642         if (options.verbosity >= 3) {
 643                 argv[argc++] = "-v";
 644                 argv[argc++] = "-v";
 645         }
 646         if (!options.progress)
 647                 argv[argc++] = "--no-progress";
 648         if (options.depth) {
 649                 struct strbuf buf = STRBUF_INIT;
 650                 strbuf_addf(&buf, "--depth=%lu", options.depth);
 651                 depth_arg = strbuf_detach(&buf, NULL);
 652                 argv[argc++] = depth_arg;
 653         }
 654         argv[argc++] = url;
 655         for (i = 0; i < nr_heads; i++) {
 656                 struct ref *ref = to_fetch[i];
 657                 if (!ref->name || !*ref->name)
 658                         die("cannot fetch by sha1 over smart http");
 659                 argv[argc++] = ref->name;
 660         }
 661         argv[argc++] = NULL;
 662
 663         memset(&rpc, 0, sizeof(rpc));
 664         rpc.service_name = "git-upload-pack",
 665         rpc.argv = argv;
 666         rpc.gzip_request = 1;
 667
 668         err = rpc_service(&rpc, heads);
 669         if (rpc.result.len)
 670                 safe_write(1, rpc.result.buf, rpc.result.len);
 671         strbuf_release(&rpc.result);
 672         free(argv);
 673         free(depth_arg);
 674         return err;
 675 }
 676
 677 static int fetch(int nr_heads, struct ref **to_fetch)
 678 {
 679         struct discovery *d = discover_refs("git-upload-pack");
 680         if (d->proto_git)
 681                 return fetch_git(d, nr_heads, to_fetch);
 682         else
 683                 return fetch_dumb(nr_heads, to_fetch);
 684 }
 685
 686 static void parse_fetch(struct strbuf *buf)
 687 {
 688         struct ref **to_fetch = NULL;
 689         struct ref *list_head = NULL;
 690         struct ref **list = &list_head;
 691         int alloc_heads = 0, nr_heads = 0;
 692
 693         do {
 694                 if (!prefixcmp(buf->buf, "fetch ")) {
 695                         char *p = buf->buf + strlen("fetch ");
 696                         char *name;
 697                         struct ref *ref;
 698                         unsigned char old_sha1[20];
 699
 700                         if (strlen(p) < 40 || get_sha1_hex(p, old_sha1))
 701                                 die("protocol error: expected sha/ref, got %s'", p);
 702                         if (p[40] == ' ')
 703                                 name = p + 41;
 704                         else if (!p[40])
 705                                 name = "";
 706                         else
 707                                 die("protocol error: expected sha/ref, got %s'", p);
 708
 709                         ref = alloc_ref(name);
 710                         hashcpy(ref->old_sha1, old_sha1);
 711
 712                         *list = ref;
 713                         list = &ref->next;
 714
 715                         ALLOC_GROW(to_fetch, nr_heads + 1, alloc_heads);
 716                         to_fetch[nr_heads++] = ref;
 717                 }
 718                 else
 719                         die("http transport does not support %s", buf->buf);
 720
 721                 strbuf_reset(buf);
 722                 if (strbuf_getline(buf, stdin, '\n') == EOF)
 723                         return;
 724                 if (!*buf->buf)
 725                         break;
 726         } while (1);
 727
 728         if (fetch(nr_heads, to_fetch))
 729                 exit(128); /* error already reported */
 730         free_refs(list_head);
 731         free(to_fetch);
 732
 733         printf("\n");
 734         fflush(stdout);
 735         strbuf_reset(buf);
 736 }
 737
 738 static int push_dav(int nr_spec, char **specs)
 739 {
 740         const char **argv = xmalloc((10 + nr_spec) * sizeof(char*));
 741         int argc = 0, i;
 742
 743         argv[argc++] = "http-push";
 744         argv[argc++] = "--helper-status";
 745         if (options.dry_run)
 746                 argv[argc++] = "--dry-run";
 747         if (options.verbosity > 1)
 748                 argv[argc++] = "--verbose";
 749         argv[argc++] = url;
 750         for (i = 0; i < nr_spec; i++)
 751                 argv[argc++] = specs[i];
 752         argv[argc++] = NULL;
 753
 754         if (run_command_v_opt(argv, RUN_GIT_CMD))
 755                 die("git-%s failed", argv[0]);
 756         free(argv);
 757         return 0;
 758 }
 759
 760 static int push_git(struct discovery *heads, int nr_spec, char **specs)
 761 {
 762         struct rpc_state rpc;
 763         const char **argv;
 764         int argc = 0, i, err;
 765
 766         argv = xmalloc((10 + nr_spec) * sizeof(char*));
 767         argv[argc++] = "send-pack";
 768         argv[argc++] = "--stateless-rpc";
 769         argv[argc++] = "--helper-status";
 770         if (options.thin)
 771                 argv[argc++] = "--thin";
 772         if (options.dry_run)
 773                 argv[argc++] = "--dry-run";
 774         if (options.verbosity > 1)
 775                 argv[argc++] = "--verbose";
 776         argv[argc++] = url;
 777         for (i = 0; i < nr_spec; i++)
 778                 argv[argc++] = specs[i];
 779         argv[argc++] = NULL;
 780
 781         memset(&rpc, 0, sizeof(rpc));
 782         rpc.service_name = "git-receive-pack",
 783         rpc.argv = argv;
 784
 785         err = rpc_service(&rpc, heads);
 786         if (rpc.result.len)
 787                 safe_write(1, rpc.result.buf, rpc.result.len);
 788         strbuf_release(&rpc.result);
 789         free(argv);
 790         return err;
 791 }
 792
 793 static int push(int nr_spec, char **specs)
 794 {
 795         struct discovery *heads = discover_refs("git-receive-pack");
 796         int ret;
 797
 798         if (heads->proto_git)
 799                 ret = push_git(heads, nr_spec, specs);
 800         else
 801                 ret = push_dav(nr_spec, specs);
 802         free_discovery(heads);
 803         return ret;
 804 }
 805
 806 static void parse_push(struct strbuf *buf)
 807 {
 808         char **specs = NULL;
 809         int alloc_spec = 0, nr_spec = 0, i;
 810
 811         do {
 812                 if (!prefixcmp(buf->buf, "push ")) {
 813                         ALLOC_GROW(specs, nr_spec + 1, alloc_spec);
 814                         specs[nr_spec++] = xstrdup(buf->buf + 5);
 815                 }
 816                 else
 817                         die("http transport does not support %s", buf->buf);
 818
 819                 strbuf_reset(buf);
 820                 if (strbuf_getline(buf, stdin, '\n') == EOF)
 821                         return;
 822                 if (!*buf->buf)
 823                         break;
 824         } while (1);
 825
 826         if (push(nr_spec, specs))
 827                 exit(128); /* error already reported */
 828         for (i = 0; i < nr_spec; i++)
 829                 free(specs[i]);
 830         free(specs);
 831
 832         printf("\n");
 833         fflush(stdout);
 834 }
 835
 836 int main(int argc, const char **argv)
 837 {
 838         struct strbuf buf = STRBUF_INIT;
 839         int nongit;
 840
 841         git_extract_argv0_path(argv[0]);
 842         setup_git_directory_gently(&nongit);
 843         if (argc < 2) {
 844                 fprintf(stderr, "Remote needed\n");
 845                 return 1;
 846         }
 847
 848         options.verbosity = 1;
 849         options.progress = !!isatty(2);
 850         options.thin = 1;
 851
 852         remote = remote_get(argv[1]);
 853
 854         if (argc > 2) {
 855                 end_url_with_slash(&buf, argv[2]);
 856         } else {
 857                 end_url_with_slash(&buf, remote->url[0]);
 858         }
 859
 860         url = strbuf_detach(&buf, NULL);
 861
 862         http_init(remote);
 863
 864         do {
 865                 if (strbuf_getline(&buf, stdin, '\n') == EOF)
 866                         break;
 867                 if (!prefixcmp(buf.buf, "fetch ")) {
 868                         if (nongit)
 869                                 die("Fetch attempted without a local repo");
 870                         parse_fetch(&buf);
 871
 872                 } else if (!strcmp(buf.buf, "list") || !prefixcmp(buf.buf, "list ")) {
 873                         int for_push = !!strstr(buf.buf + 4, "for-push");
 874                         output_refs(get_refs(for_push));
 875
 876                 } else if (!prefixcmp(buf.buf, "push ")) {
 877                         parse_push(&buf);
 878
 879                 } else if (!prefixcmp(buf.buf, "option ")) {
 880                         char *name = buf.buf + strlen("option ");
 881                         char *value = strchr(name, ' ');
 882                         int result;
 883
 884                         if (value)
 885                                 *value++ = '\0';
 886                         else
 887                                 value = "true";
 888
 889                         result = set_option(name, value);
 890                         if (!result)
 891                                 printf("ok\n");
 892                         else if (result < 0)
 893                                 printf("error invalid value\n");
 894                         else
 895                                 printf("unsupported\n");
 896                         fflush(stdout);
 897
 898                 } else if (!strcmp(buf.buf, "capabilities")) {
 899                         printf("fetch\n");
 900                         printf("option\n");
 901                         printf("push\n");
 902                         printf("\n");
 903                         fflush(stdout);
 904                 } else {
 905                         return 1;
 906                 }
 907                 strbuf_reset(&buf);
 908         } while (1);
 909
 910         http_cleanup();
 911
 912         return 0;
 913 }