remote-curl.c

   1 #define USE_THE_REPOSITORY_VARIABLE
   2
   3 #include "git-compat-util.h"
   4 #include "git-curl-compat.h"
   5 #include "config.h"
   6 #include "environment.h"
   7 #include "gettext.h"
   8 #include "hex.h"
   9 #include "remote.h"
  10 #include "connect.h"
  11 #include "strbuf.h"
  12 #include "walker.h"
  13 #include "http.h"
  14 #include "run-command.h"
  15 #include "pkt-line.h"
  16 #include "string-list.h"
  17 #include "strvec.h"
  18 #include "credential.h"
  19 #include "oid-array.h"
  20 #include "send-pack.h"
  21 #include "setup.h"
  22 #include "protocol.h"
  23 #include "quote.h"
  24 #include "trace2.h"
  25 #include "transport.h"
  26 #include "url.h"
  27 #include "write-or-die.h"
  28
  29 static struct remote *remote;
  30 /* always ends with a trailing slash */
  31 static struct strbuf url = STRBUF_INIT;
  32
  33 struct options {
  34         int verbosity;
  35         unsigned long depth;
  36         char *deepen_since;
  37         struct string_list deepen_not;
  38         struct string_list push_options;
  39         char *filter;
  40         unsigned progress : 1,
  41                 check_self_contained_and_connected : 1,
  42                 cloning : 1,
  43                 update_shallow : 1,
  44                 followtags : 1,
  45                 dry_run : 1,
  46                 thin : 1,
  47                 /* One of the SEND_PACK_PUSH_CERT_* constants. */
  48                 push_cert : 2,
  49                 deepen_relative : 1,
  50
  51                 /* see documentation of corresponding flag in fetch-pack.h */
  52                 from_promisor : 1,
  53
  54                 refetch : 1,
  55                 atomic : 1,
  56                 object_format : 1,
  57                 force_if_includes : 1;
  58         const struct git_hash_algo *hash_algo;
  59 };
  60 static struct options options;
  61 static struct string_list cas_options = STRING_LIST_INIT_DUP;
  62
  63 static int set_option(const char *name, size_t namelen, const char *value)
  64 {
  65         if (!strncmp(name, "verbosity", namelen)) {
  66                 char *end;
  67                 int v = strtol(value, &end, 10);
  68                 if (value == end || *end)
  69                         return -1;
  70                 options.verbosity = v;
  71                 return 0;
  72         }
  73         else if (!strncmp(name, "progress", namelen)) {
  74                 if (!strcmp(value, "true"))
  75                         options.progress = 1;
  76                 else if (!strcmp(value, "false"))
  77                         options.progress = 0;
  78                 else
  79                         return -1;
  80                 return 0;
  81         }
  82         else if (!strncmp(name, "depth", namelen)) {
  83                 char *end;
  84                 unsigned long v = strtoul(value, &end, 10);
  85                 if (value == end || *end)
  86                         return -1;
  87                 options.depth = v;
  88                 return 0;
  89         }
  90         else if (!strncmp(name, "deepen-since", namelen)) {
  91                 options.deepen_since = xstrdup(value);
  92                 return 0;
  93         }
  94         else if (!strncmp(name, "deepen-not", namelen)) {
  95                 string_list_append(&options.deepen_not, value);
  96                 return 0;
  97         }
  98         else if (!strncmp(name, "deepen-relative", namelen)) {
  99                 if (!strcmp(value, "true"))
 100                         options.deepen_relative = 1;
 101                 else if (!strcmp(value, "false"))
 102                         options.deepen_relative = 0;
 103                 else
 104                         return -1;
 105                 return 0;
 106         }
 107         else if (!strncmp(name, "followtags", namelen)) {
 108                 if (!strcmp(value, "true"))
 109                         options.followtags = 1;
 110                 else if (!strcmp(value, "false"))
 111                         options.followtags = 0;
 112                 else
 113                         return -1;
 114                 return 0;
 115         }
 116         else if (!strncmp(name, "dry-run", namelen)) {
 117                 if (!strcmp(value, "true"))
 118                         options.dry_run = 1;
 119                 else if (!strcmp(value, "false"))
 120                         options.dry_run = 0;
 121                 else
 122                         return -1;
 123                 return 0;
 124         }
 125         else if (!strncmp(name, "check-connectivity", namelen)) {
 126                 if (!strcmp(value, "true"))
 127                         options.check_self_contained_and_connected = 1;
 128                 else if (!strcmp(value, "false"))
 129                         options.check_self_contained_and_connected = 0;
 130                 else
 131                         return -1;
 132                 return 0;
 133         }
 134         else if (!strncmp(name, "cas", namelen)) {
 135                 struct strbuf val = STRBUF_INIT;
 136                 strbuf_addstr(&val, "--force-with-lease=");
 137                 if (*value != '"')
 138                         strbuf_addstr(&val, value);
 139                 else if (unquote_c_style(&val, value, NULL))
 140                         return -1;
 141                 string_list_append(&cas_options, val.buf);
 142                 strbuf_release(&val);
 143                 return 0;
 144         } else if (!strncmp(name, TRANS_OPT_FORCE_IF_INCLUDES, namelen)) {
 145                 if (!strcmp(value, "true"))
 146                         options.force_if_includes = 1;
 147                 else if (!strcmp(value, "false"))
 148                         options.force_if_includes = 0;
 149                 else
 150                         return -1;
 151                 return 0;
 152         } else if (!strncmp(name, "cloning", namelen)) {
 153                 if (!strcmp(value, "true"))
 154                         options.cloning = 1;
 155                 else if (!strcmp(value, "false"))
 156                         options.cloning = 0;
 157                 else
 158                         return -1;
 159                 return 0;
 160         } else if (!strncmp(name, "update-shallow", namelen)) {
 161                 if (!strcmp(value, "true"))
 162                         options.update_shallow = 1;
 163                 else if (!strcmp(value, "false"))
 164                         options.update_shallow = 0;
 165                 else
 166                         return -1;
 167                 return 0;
 168         } else if (!strncmp(name, "pushcert", namelen)) {
 169                 if (!strcmp(value, "true"))
 170                         options.push_cert = SEND_PACK_PUSH_CERT_ALWAYS;
 171                 else if (!strcmp(value, "false"))
 172                         options.push_cert = SEND_PACK_PUSH_CERT_NEVER;
 173                 else if (!strcmp(value, "if-asked"))
 174                         options.push_cert = SEND_PACK_PUSH_CERT_IF_ASKED;
 175                 else
 176                         return -1;
 177                 return 0;
 178         } else if (!strncmp(name, "atomic", namelen)) {
 179                 if (!strcmp(value, "true"))
 180                         options.atomic = 1;
 181                 else if (!strcmp(value, "false"))
 182                         options.atomic = 0;
 183                 else
 184                         return -1;
 185                 return 0;
 186         } else if (!strncmp(name, "push-option", namelen)) {
 187                 if (*value != '"')
 188                         string_list_append(&options.push_options, value);
 189                 else {
 190                         struct strbuf unquoted = STRBUF_INIT;
 191                         if (unquote_c_style(&unquoted, value, NULL) < 0)
 192                                 die(_("invalid quoting in push-option value: '%s'"), value);
 193                         string_list_append_nodup(&options.push_options,
 194                                                  strbuf_detach(&unquoted, NULL));
 195                 }
 196                 return 0;
 197         } else if (!strncmp(name, "family", namelen)) {
 198                 if (!strcmp(value, "ipv4"))
 199                         git_curl_ipresolve = CURL_IPRESOLVE_V4;
 200                 else if (!strcmp(value, "ipv6"))
 201                         git_curl_ipresolve = CURL_IPRESOLVE_V6;
 202                 else if (!strcmp(value, "all"))
 203                         git_curl_ipresolve = CURL_IPRESOLVE_WHATEVER;
 204                 else
 205                         return -1;
 206                 return 0;
 207         } else if (!strncmp(name, "from-promisor", namelen)) {
 208                 options.from_promisor = 1;
 209                 return 0;
 210         } else if (!strncmp(name, "refetch", namelen)) {
 211                 options.refetch = 1;
 212                 return 0;
 213         } else if (!strncmp(name, "filter", namelen)) {
 214                 options.filter = xstrdup(value);
 215                 return 0;
 216         } else if (!strncmp(name, "object-format", namelen)) {
 217                 options.object_format = 1;
 218                 if (strcmp(value, "true"))
 219                         die(_("unknown value for object-format: %s"), value);
 220                 return 0;
 221         } else {
 222                 return 1 /* unsupported */;
 223         }
 224 }
 225
 226 struct discovery {
 227         char *service;
 228         char *buf_alloc;
 229         char *buf;
 230         size_t len;
 231         struct ref *refs;
 232         struct oid_array shallow;
 233         enum protocol_version version;
 234         unsigned proto_git : 1;
 235 };
 236 static struct discovery *last_discovery;
 237
 238 static struct ref *parse_git_refs(struct discovery *heads, int for_push)
 239 {
 240         struct ref *list = NULL;
 241         struct packet_reader reader;
 242
 243         packet_reader_init(&reader, -1, heads->buf, heads->len,
 244                            PACKET_READ_CHOMP_NEWLINE |
 245                            PACKET_READ_GENTLE_ON_EOF |
 246                            PACKET_READ_DIE_ON_ERR_PACKET);
 247
 248         heads->version = discover_version(&reader);
 249         switch (heads->version) {
 250         case protocol_v2:
 251                 /*
 252                  * Do nothing.  This isn't a list of refs but rather a
 253                  * capability advertisement.  Client would have run
 254                  * 'stateless-connect' so we'll dump this capability listing
 255                  * and let them request the refs themselves.
 256                  */
 257                 break;
 258         case protocol_v1:
 259         case protocol_v0:
 260                 get_remote_heads(&reader, &list, for_push ? REF_NORMAL : 0,
 261                                  NULL, &heads->shallow);
 262                 options.hash_algo = reader.hash_algo;
 263                 break;
 264         case protocol_unknown_version:
 265                 BUG("unknown protocol version");
 266         }
 267
 268         return list;
 269 }
 270
 271 /*
 272  * Try to detect the hash algorithm used by the remote repository when using
 273  * the dumb HTTP transport. As dumb transports cannot tell us the object hash
 274  * directly have to derive it from the advertised ref lengths.
 275  */
 276 static const struct git_hash_algo *detect_hash_algo(struct discovery *heads)
 277 {
 278         const char *p = memchr(heads->buf, '\t', heads->len);
 279         int algo;
 280
 281         /*
 282          * In case the remote has no refs we have no way to reliably determine
 283          * the object hash used by that repository. In that case we simply fall
 284          * back to SHA1, which may or may not be correct.
 285          */
 286         if (!p)
 287                 return &hash_algos[GIT_HASH_SHA1];
 288
 289         algo = hash_algo_by_length((p - heads->buf) / 2);
 290         if (algo == GIT_HASH_UNKNOWN)
 291                 return NULL;
 292         return &hash_algos[algo];
 293 }
 294
 295 static struct ref *parse_info_refs(struct discovery *heads)
 296 {
 297         char *data, *start, *mid;
 298         char *ref_name;
 299         int i = 0;
 300
 301         struct ref *refs = NULL;
 302         struct ref *ref = NULL;
 303         struct ref *last_ref = NULL;
 304
 305         options.hash_algo = detect_hash_algo(heads);
 306         if (!options.hash_algo)
 307                 die("%sinfo/refs not valid: could not determine hash algorithm; "
 308                     "is this a git repository?",
 309                     transport_anonymize_url(url.buf));
 310
 311         /*
 312          * Set the repository's hash algo to whatever we have just detected.
 313          * This ensures that we can correctly parse the remote references.
 314          */
 315         repo_set_hash_algo(the_repository, hash_algo_by_ptr(options.hash_algo));
 316
 317         data = heads->buf;
 318         start = NULL;
 319         mid = data;
 320         while (i < heads->len) {
 321                 if (!start) {
 322                         start = &data[i];
 323                 }
 324                 if (data[i] == '\t')
 325                         mid = &data[i];
 326                 if (data[i] == '\n') {
 327                         if (mid - start != options.hash_algo->hexsz)
 328                                 die(_("%sinfo/refs not valid: is this a git repository?"),
 329                                     transport_anonymize_url(url.buf));
 330                         data[i] = 0;
 331                         ref_name = mid + 1;
 332                         ref = alloc_ref(ref_name);
 333                         get_oid_hex_algop(start, &ref->old_oid, options.hash_algo);
 334                         if (!refs)
 335                                 refs = ref;
 336                         if (last_ref)
 337                                 last_ref->next = ref;
 338                         last_ref = ref;
 339                         start = NULL;
 340                 }
 341                 i++;
 342         }
 343
 344         ref = alloc_ref("HEAD");
 345         if (!http_fetch_ref(url.buf, ref) &&
 346             !resolve_remote_symref(ref, refs)) {
 347                 ref->next = refs;
 348                 refs = ref;
 349         } else {
 350                 free_one_ref(ref);
 351         }
 352
 353         return refs;
 354 }
 355
 356 static void free_discovery(struct discovery *d)
 357 {
 358         if (d) {
 359                 if (d == last_discovery)
 360                         last_discovery = NULL;
 361                 free(d->shallow.oid);
 362                 free(d->buf_alloc);
 363                 free_refs(d->refs);
 364                 free(d->service);
 365                 free(d);
 366         }
 367 }
 368
 369 static int show_http_message(struct strbuf *type, struct strbuf *charset,
 370                              struct strbuf *msg)
 371 {
 372         const char *p, *eol;
 373
 374         /*
 375          * We only show text/plain parts, as other types are likely
 376          * to be ugly to look at on the user's terminal.
 377          */
 378         if (strcmp(type->buf, "text/plain"))
 379                 return -1;
 380         if (charset->len)
 381                 strbuf_reencode(msg, charset->buf, get_log_output_encoding());
 382
 383         strbuf_trim(msg);
 384         if (!msg->len)
 385                 return -1;
 386
 387         p = msg->buf;
 388         do {
 389                 eol = strchrnul(p, '\n');
 390                 fprintf(stderr, "remote: %.*s\n", (int)(eol - p), p);
 391                 p = eol + 1;
 392         } while(*eol);
 393         return 0;
 394 }
 395
 396 static int get_protocol_http_header(enum protocol_version version,
 397                                     struct strbuf *header)
 398 {
 399         if (version > 0) {
 400                 strbuf_addf(header, GIT_PROTOCOL_HEADER ": version=%d",
 401                             version);
 402
 403                 return 1;
 404         }
 405
 406         return 0;
 407 }
 408
 409 static void check_smart_http(struct discovery *d, const char *service,
 410                              struct strbuf *type)
 411 {
 412         const char *p;
 413         struct packet_reader reader;
 414
 415         /*
 416          * If we don't see x-$service-advertisement, then it's not smart-http.
 417          * But once we do, we commit to it and assume any other protocol
 418          * violations are hard errors.
 419          */
 420         if (!skip_prefix(type->buf, "application/x-", &p) ||
 421             !skip_prefix(p, service, &p) ||
 422             strcmp(p, "-advertisement"))
 423                 return;
 424
 425         packet_reader_init(&reader, -1, d->buf, d->len,
 426                            PACKET_READ_CHOMP_NEWLINE |
 427                            PACKET_READ_DIE_ON_ERR_PACKET);
 428         if (packet_reader_read(&reader) != PACKET_READ_NORMAL)
 429                 die(_("invalid server response; expected service, got flush packet"));
 430
 431         if (skip_prefix(reader.line, "# service=", &p) && !strcmp(p, service)) {
 432                 /*
 433                  * The header can include additional metadata lines, up
 434                  * until a packet flush marker.  Ignore these now, but
 435                  * in the future we might start to scan them.
 436                  */
 437                 for (;;) {
 438                         packet_reader_read(&reader);
 439                         if (reader.pktlen <= 0) {
 440                                 break;
 441                         }
 442                 }
 443
 444                 /*
 445                  * v0 smart http; callers expect us to soak up the
 446                  * service and header packets
 447                  */
 448                 d->buf = reader.src_buffer;
 449                 d->len = reader.src_len;
 450                 d->proto_git = 1;
 451
 452         } else if (!strcmp(reader.line, "version 2")) {
 453                 /*
 454                  * v2 smart http; do not consume version packet, which will
 455                  * be handled elsewhere.
 456                  */
 457                 d->proto_git = 1;
 458
 459         } else {
 460                 die(_("invalid server response; got '%s'"), reader.line);
 461         }
 462 }
 463
 464 static struct discovery *discover_refs(const char *service, int for_push)
 465 {
 466         struct strbuf type = STRBUF_INIT;
 467         struct strbuf charset = STRBUF_INIT;
 468         struct strbuf buffer = STRBUF_INIT;
 469         struct strbuf refs_url = STRBUF_INIT;
 470         struct strbuf effective_url = STRBUF_INIT;
 471         struct strbuf protocol_header = STRBUF_INIT;
 472         struct string_list extra_headers = STRING_LIST_INIT_DUP;
 473         struct discovery *last = last_discovery;
 474         int http_ret, maybe_smart = 0;
 475         struct http_get_options http_options;
 476         enum protocol_version version = get_protocol_version_config();
 477
 478         if (last && !strcmp(service, last->service))
 479                 return last;
 480         free_discovery(last);
 481
 482         strbuf_addf(&refs_url, "%sinfo/refs", url.buf);
 483         if ((starts_with(url.buf, "http://") || starts_with(url.buf, "https://")) &&
 484              git_env_bool("GIT_SMART_HTTP", 1)) {
 485                 maybe_smart = 1;
 486                 if (!strchr(url.buf, '?'))
 487                         strbuf_addch(&refs_url, '?');
 488                 else
 489                         strbuf_addch(&refs_url, '&');
 490                 strbuf_addf(&refs_url, "service=%s", service);
 491         }
 492
 493         /*
 494          * NEEDSWORK: If we are trying to use protocol v2 and we are planning
 495          * to perform any operation that doesn't involve upload-pack (i.e., a
 496          * fetch, ls-remote, etc), then fallback to v0 since we don't know how
 497          * to do anything else (like push or remote archive) via v2.
 498          */
 499         if (version == protocol_v2 && strcmp("git-upload-pack", service))
 500                 version = protocol_v0;
 501
 502         /* Add the extra Git-Protocol header */
 503         if (get_protocol_http_header(version, &protocol_header))
 504                 string_list_append(&extra_headers, protocol_header.buf);
 505
 506         memset(&http_options, 0, sizeof(http_options));
 507         http_options.content_type = &type;
 508         http_options.charset = &charset;
 509         http_options.effective_url = &effective_url;
 510         http_options.base_url = &url;
 511         http_options.extra_headers = &extra_headers;
 512         http_options.initial_request = 1;
 513         http_options.no_cache = 1;
 514
 515         http_ret = http_get_strbuf(refs_url.buf, &buffer, &http_options);
 516         switch (http_ret) {
 517         case HTTP_OK:
 518                 break;
 519         case HTTP_MISSING_TARGET:
 520                 show_http_message(&type, &charset, &buffer);
 521                 die(_("repository '%s' not found"),
 522                     transport_anonymize_url(url.buf));
 523         case HTTP_NOAUTH:
 524                 show_http_message(&type, &charset, &buffer);
 525                 die(_("Authentication failed for '%s'"),
 526                     transport_anonymize_url(url.buf));
 527         case HTTP_NOMATCHPUBLICKEY:
 528                 show_http_message(&type, &charset, &buffer);
 529                 die(_("unable to access '%s' with http.pinnedPubkey configuration: %s"),
 530                     transport_anonymize_url(url.buf), curl_errorstr);
 531         default:
 532                 show_http_message(&type, &charset, &buffer);
 533                 die(_("unable to access '%s': %s"),
 534                     transport_anonymize_url(url.buf), curl_errorstr);
 535         }
 536
 537         if (options.verbosity && !starts_with(refs_url.buf, url.buf)) {
 538                 char *u = transport_anonymize_url(url.buf);
 539                 warning(_("redirecting to %s"), u);
 540                 free(u);
 541         }
 542
 543         last= xcalloc(1, sizeof(*last_discovery));
 544         last->service = xstrdup(service);
 545         last->buf_alloc = strbuf_detach(&buffer, &last->len);
 546         last->buf = last->buf_alloc;
 547
 548         if (maybe_smart)
 549                 check_smart_http(last, service, &type);
 550
 551         if (last->proto_git)
 552                 last->refs = parse_git_refs(last, for_push);
 553         else
 554                 last->refs = parse_info_refs(last);
 555
 556         strbuf_release(&refs_url);
 557         strbuf_release(&type);
 558         strbuf_release(&charset);
 559         strbuf_release(&effective_url);
 560         strbuf_release(&buffer);
 561         strbuf_release(&protocol_header);
 562         string_list_clear(&extra_headers, 0);
 563         last_discovery = last;
 564         return last;
 565 }
 566
 567 static struct ref *get_refs(int for_push)
 568 {
 569         struct discovery *heads;
 570
 571         if (for_push)
 572                 heads = discover_refs("git-receive-pack", for_push);
 573         else
 574                 heads = discover_refs("git-upload-pack", for_push);
 575
 576         return heads->refs;
 577 }
 578
 579 static void output_refs(struct ref *refs)
 580 {
 581         struct ref *posn;
 582         if (options.object_format && options.hash_algo) {
 583                 printf(":object-format %s\n", options.hash_algo->name);
 584                 repo_set_hash_algo(the_repository,
 585                                 hash_algo_by_ptr(options.hash_algo));
 586         }
 587         for (posn = refs; posn; posn = posn->next) {
 588                 if (posn->symref)
 589                         printf("@%s %s\n", posn->symref, posn->name);
 590                 else
 591                         printf("%s %s\n", hash_to_hex_algop(posn->old_oid.hash,
 592                                                             options.hash_algo),
 593                                           posn->name);
 594         }
 595         printf("\n");
 596         fflush(stdout);
 597 }
 598
 599 struct rpc_state {
 600         const char *service_name;
 601         char *service_url;
 602         char *hdr_content_type;
 603         char *hdr_accept;
 604         char *hdr_accept_language;
 605         char *protocol_header;
 606         char *buf;
 607         size_t alloc;
 608         size_t len;
 609         size_t pos;
 610         int in;
 611         int out;
 612         int any_written;
 613         unsigned gzip_request : 1;
 614         unsigned initial_buffer : 1;
 615
 616         /*
 617          * Whenever a pkt-line is read into buf, append the 4 characters
 618          * denoting its length before appending the payload.
 619          */
 620         unsigned write_line_lengths : 1;
 621
 622         /*
 623          * Used by rpc_out; initialize to 0. This is true if a flush has been
 624          * read, but the corresponding line length (if write_line_lengths is
 625          * true) and EOF have not been sent to libcurl. Since each flush marks
 626          * the end of a request, each flush must be completely sent before any
 627          * further reading occurs.
 628          */
 629         unsigned flush_read_but_not_sent : 1;
 630 };
 631
 632 #define RPC_STATE_INIT { 0 }
 633
 634 /*
 635  * Appends the result of reading from rpc->out to the string represented by
 636  * rpc->buf and rpc->len if there is enough space. Returns 1 if there was
 637  * enough space, 0 otherwise.
 638  *
 639  * If rpc->write_line_lengths is true, appends the line length as a 4-byte
 640  * hexadecimal string before appending the result described above.
 641  *
 642  * Writes the total number of bytes appended into appended.
 643  */
 644 static int rpc_read_from_out(struct rpc_state *rpc, int options,
 645                              size_t *appended,
 646                              enum packet_read_status *status) {
 647         size_t left;
 648         char *buf;
 649         int pktlen_raw;
 650
 651         if (rpc->write_line_lengths) {
 652                 left = rpc->alloc - rpc->len - 4;
 653                 buf = rpc->buf + rpc->len + 4;
 654         } else {
 655                 left = rpc->alloc - rpc->len;
 656                 buf = rpc->buf + rpc->len;
 657         }
 658
 659         if (left < LARGE_PACKET_MAX)
 660                 return 0;
 661
 662         *status = packet_read_with_status(rpc->out, NULL, NULL, buf,
 663                         left, &pktlen_raw, options);
 664         if (*status != PACKET_READ_EOF) {
 665                 *appended = pktlen_raw + (rpc->write_line_lengths ? 4 : 0);
 666                 rpc->len += *appended;
 667         }
 668
 669         if (rpc->write_line_lengths) {
 670                 switch (*status) {
 671                 case PACKET_READ_EOF:
 672                         if (!(options & PACKET_READ_GENTLE_ON_EOF))
 673                                 die(_("shouldn't have EOF when not gentle on EOF"));
 674                         break;
 675                 case PACKET_READ_NORMAL:
 676                         set_packet_header(buf - 4, *appended);
 677                         break;
 678                 case PACKET_READ_DELIM:
 679                         memcpy(buf - 4, "0001", 4);
 680                         break;
 681                 case PACKET_READ_FLUSH:
 682                         memcpy(buf - 4, "0000", 4);
 683                         break;
 684                 case PACKET_READ_RESPONSE_END:
 685                         die(_("remote server sent unexpected response end packet"));
 686                 }
 687         }
 688
 689         return 1;
 690 }
 691
 692 static size_t rpc_out(void *ptr, size_t eltsize,
 693                 size_t nmemb, void *buffer_)
 694 {
 695         size_t max = eltsize * nmemb;
 696         struct rpc_state *rpc = buffer_;
 697         size_t avail = rpc->len - rpc->pos;
 698         enum packet_read_status status;
 699
 700         if (!avail) {
 701                 rpc->initial_buffer = 0;
 702                 rpc->len = 0;
 703                 rpc->pos = 0;
 704                 if (!rpc->flush_read_but_not_sent) {
 705                         if (!rpc_read_from_out(rpc, 0, &avail, &status))
 706                                 BUG("The entire rpc->buf should be larger than LARGE_PACKET_MAX");
 707                         if (status == PACKET_READ_FLUSH)
 708                                 rpc->flush_read_but_not_sent = 1;
 709                 }
 710                 /*
 711                  * If flush_read_but_not_sent is true, we have already read one
 712                  * full request but have not fully sent it + EOF, which is why
 713                  * we need to refrain from reading.
 714                  */
 715         }
 716         if (rpc->flush_read_but_not_sent) {
 717                 if (!avail) {
 718                         /*
 719                          * The line length either does not need to be sent at
 720                          * all or has already been completely sent. Now we can
 721                          * return 0, indicating EOF, meaning that the flush has
 722                          * been fully sent.
 723                          */
 724                         rpc->flush_read_but_not_sent = 0;
 725                         return 0;
 726                 }
 727                 /*
 728                  * If avail is non-zero, the line length for the flush still
 729                  * hasn't been fully sent. Proceed with sending the line
 730                  * length.
 731                  */
 732         }
 733
 734         if (max < avail)
 735                 avail = max;
 736         memcpy(ptr, rpc->buf + rpc->pos, avail);
 737         rpc->pos += avail;
 738         return avail;
 739 }
 740
 741 static int rpc_seek(void *clientp, curl_off_t offset, int origin)
 742 {
 743         struct rpc_state *rpc = clientp;
 744
 745         if (origin != SEEK_SET)
 746                 BUG("rpc_seek only handles SEEK_SET, not %d", origin);
 747
 748         if (rpc->initial_buffer) {
 749                 if (offset < 0 || offset > rpc->len) {
 750                         error("curl seek would be outside of rpc buffer");
 751                         return CURL_SEEKFUNC_FAIL;
 752                 }
 753                 rpc->pos = offset;
 754                 return CURL_SEEKFUNC_OK;
 755         }
 756         error(_("unable to rewind rpc post data - try increasing http.postBuffer"));
 757         return CURL_SEEKFUNC_FAIL;
 758 }
 759
 760 struct check_pktline_state {
 761         char len_buf[4];
 762         int len_filled;
 763         int remaining;
 764 };
 765
 766 static void check_pktline(struct check_pktline_state *state, const char *ptr, size_t size)
 767 {
 768         while (size) {
 769                 if (!state->remaining) {
 770                         int digits_remaining = 4 - state->len_filled;
 771                         if (digits_remaining > size)
 772                                 digits_remaining = size;
 773                         memcpy(&state->len_buf[state->len_filled], ptr, digits_remaining);
 774                         state->len_filled += digits_remaining;
 775                         ptr += digits_remaining;
 776                         size -= digits_remaining;
 777
 778                         if (state->len_filled == 4) {
 779                                 state->remaining = packet_length(state->len_buf,
 780                                                                  sizeof(state->len_buf));
 781                                 if (state->remaining < 0) {
 782                                         die(_("remote-curl: bad line length character: %.4s"), state->len_buf);
 783                                 } else if (state->remaining == 2) {
 784                                         die(_("remote-curl: unexpected response end packet"));
 785                                 } else if (state->remaining < 4) {
 786                                         state->remaining = 0;
 787                                 } else {
 788                                         state->remaining -= 4;
 789                                 }
 790                                 state->len_filled = 0;
 791                         }
 792                 }
 793
 794                 if (state->remaining) {
 795                         int remaining = state->remaining;
 796                         if (remaining > size)
 797                                 remaining = size;
 798                         ptr += remaining;
 799                         size -= remaining;
 800                         state->remaining -= remaining;
 801                 }
 802         }
 803 }
 804
 805 struct rpc_in_data {
 806         struct rpc_state *rpc;
 807         struct active_request_slot *slot;
 808         int check_pktline;
 809         struct check_pktline_state pktline_state;
 810 };
 811
 812 /*
 813  * A callback for CURLOPT_WRITEFUNCTION. The return value is the bytes consumed
 814  * from ptr.
 815  */
 816 static size_t rpc_in(char *ptr, size_t eltsize,
 817                 size_t nmemb, void *buffer_)
 818 {
 819         size_t size = eltsize * nmemb;
 820         struct rpc_in_data *data = buffer_;
 821         long response_code;
 822
 823         if (curl_easy_getinfo(data->slot->curl, CURLINFO_RESPONSE_CODE,
 824                               &response_code) != CURLE_OK)
 825                 return size;
 826         if (response_code >= 300)
 827                 return size;
 828         if (size)
 829                 data->rpc->any_written = 1;
 830         if (data->check_pktline)
 831                 check_pktline(&data->pktline_state, ptr, size);
 832         write_or_die(data->rpc->in, ptr, size);
 833         return size;
 834 }
 835
 836 static int run_slot(struct active_request_slot *slot,
 837                     struct slot_results *results)
 838 {
 839         int err;
 840         struct slot_results results_buf;
 841
 842         if (!results)
 843                 results = &results_buf;
 844
 845         err = run_one_slot(slot, results);
 846
 847         if (err != HTTP_OK && err != HTTP_REAUTH) {
 848                 struct strbuf msg = STRBUF_INIT;
 849                 if (results->http_code && results->http_code != 200)
 850                         strbuf_addf(&msg, "HTTP %ld", results->http_code);
 851                 if (results->curl_result != CURLE_OK) {
 852                         if (msg.len)
 853                                 strbuf_addch(&msg, ' ');
 854                         strbuf_addf(&msg, "curl %d", results->curl_result);
 855                         if (curl_errorstr[0]) {
 856                                 strbuf_addch(&msg, ' ');
 857                                 strbuf_addstr(&msg, curl_errorstr);
 858                         }
 859                 }
 860                 error(_("RPC failed; %s"), msg.buf);
 861                 strbuf_release(&msg);
 862         }
 863
 864         return err;
 865 }
 866
 867 static int probe_rpc(struct rpc_state *rpc, struct slot_results *results)
 868 {
 869         struct active_request_slot *slot;
 870         struct curl_slist *headers = http_copy_default_headers();
 871         struct strbuf buf = STRBUF_INIT;
 872         int err;
 873
 874         slot = get_active_slot();
 875
 876         headers = curl_slist_append(headers, rpc->hdr_content_type);
 877         headers = curl_slist_append(headers, rpc->hdr_accept);
 878
 879         curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
 880         curl_easy_setopt(slot->curl, CURLOPT_POST, 1);
 881         curl_easy_setopt(slot->curl, CURLOPT_URL, rpc->service_url);
 882         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, NULL);
 883         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, "0000");
 884         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDSIZE, 4);
 885         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
 886         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
 887         curl_easy_setopt(slot->curl, CURLOPT_WRITEDATA, &buf);
 888
 889         err = run_slot(slot, results);
 890
 891         curl_slist_free_all(headers);
 892         strbuf_release(&buf);
 893         return err;
 894 }
 895
 896 static curl_off_t xcurl_off_t(size_t len)
 897 {
 898         uintmax_t size = len;
 899         if (size > maximum_signed_value_of_type(curl_off_t))
 900                 die(_("cannot handle pushes this big"));
 901         return (curl_off_t)size;
 902 }
 903
 904 /*
 905  * If flush_received is true, do not attempt to read any more; just use what's
 906  * in rpc->buf.
 907  */
 908 static int post_rpc(struct rpc_state *rpc, int stateless_connect, int flush_received)
 909 {
 910         struct active_request_slot *slot;
 911         struct curl_slist *headers = NULL;
 912         int use_gzip = rpc->gzip_request;
 913         char *gzip_body = NULL;
 914         size_t gzip_size = 0;
 915         int err, large_request = 0;
 916         int needs_100_continue = 0;
 917         struct rpc_in_data rpc_in_data;
 918
 919         /* Try to load the entire request, if we can fit it into the
 920          * allocated buffer space we can use HTTP/1.0 and avoid the
 921          * chunked encoding mess.
 922          */
 923         if (!flush_received) {
 924                 while (1) {
 925                         size_t n;
 926                         enum packet_read_status status;
 927
 928                         if (!rpc_read_from_out(rpc, 0, &n, &status)) {
 929                                 large_request = 1;
 930                                 use_gzip = 0;
 931                                 break;
 932                         }
 933                         if (status == PACKET_READ_FLUSH)
 934                                 break;
 935                 }
 936         }
 937
 938         if (large_request) {
 939                 struct slot_results results;
 940
 941                 do {
 942                         err = probe_rpc(rpc, &results);
 943                         if (err == HTTP_REAUTH)
 944                                 credential_fill(&http_auth, 0);
 945                 } while (err == HTTP_REAUTH);
 946                 if (err != HTTP_OK)
 947                         return -1;
 948
 949                 if (results.auth_avail & CURLAUTH_GSSNEGOTIATE || http_auth.authtype)
 950                         needs_100_continue = 1;
 951         }
 952
 953 retry:
 954         headers = http_copy_default_headers();
 955         headers = curl_slist_append(headers, rpc->hdr_content_type);
 956         headers = curl_slist_append(headers, rpc->hdr_accept);
 957         headers = curl_slist_append(headers, needs_100_continue ?
 958                 "Expect: 100-continue" : "Expect:");
 959
 960         headers = http_append_auth_header(&http_auth, headers);
 961
 962         /* Add Accept-Language header */
 963         if (rpc->hdr_accept_language)
 964                 headers = curl_slist_append(headers, rpc->hdr_accept_language);
 965
 966         /* Add the extra Git-Protocol header */
 967         if (rpc->protocol_header)
 968                 headers = curl_slist_append(headers, rpc->protocol_header);
 969
 970         slot = get_active_slot();
 971
 972         curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
 973         curl_easy_setopt(slot->curl, CURLOPT_POST, 1);
 974         curl_easy_setopt(slot->curl, CURLOPT_URL, rpc->service_url);
 975         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "");
 976
 977         if (large_request) {
 978                 /* The request body is large and the size cannot be predicted.
 979                  * We must use chunked encoding to send it.
 980                  */
 981 #ifdef GIT_CURL_NEED_TRANSFER_ENCODING_HEADER
 982                 headers = curl_slist_append(headers, "Transfer-Encoding: chunked");
 983 #endif
 984                 rpc->initial_buffer = 1;
 985                 curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, rpc_out);
 986                 curl_easy_setopt(slot->curl, CURLOPT_INFILE, rpc);
 987                 curl_easy_setopt(slot->curl, CURLOPT_SEEKFUNCTION, rpc_seek);
 988                 curl_easy_setopt(slot->curl, CURLOPT_SEEKDATA, rpc);
 989                 if (options.verbosity > 1) {
 990                         fprintf(stderr, "POST %s (chunked)\n", rpc->service_name);
 991                         fflush(stderr);
 992                 }
 993
 994         } else if (gzip_body) {
 995                 /*
 996                  * If we are looping to retry authentication, then the previous
 997                  * run will have set up the headers and gzip buffer already,
 998                  * and we just need to send it.
 999                  */
1000                 curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, gzip_body);
1001                 curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDSIZE_LARGE, xcurl_off_t(gzip_size));
1002
1003         } else if (use_gzip && 1024 < rpc->len) {
1004                 /* The client backend isn't giving us compressed data so
1005                  * we can try to deflate it ourselves, this may save on
1006                  * the transfer time.
1007                  */
1008                 git_zstream stream;
1009                 int ret;
1010
1011                 git_deflate_init_gzip(&stream, Z_BEST_COMPRESSION);
1012                 gzip_size = git_deflate_bound(&stream, rpc->len);
1013                 gzip_body = xmalloc(gzip_size);
1014
1015                 stream.next_in = (unsigned char *)rpc->buf;
1016                 stream.avail_in = rpc->len;
1017                 stream.next_out = (unsigned char *)gzip_body;
1018                 stream.avail_out = gzip_size;
1019
1020                 ret = git_deflate(&stream, Z_FINISH);
1021                 if (ret != Z_STREAM_END)
1022                         die(_("cannot deflate request; zlib deflate error %d"), ret);
1023
1024                 ret = git_deflate_end_gently(&stream);
1025                 if (ret != Z_OK)
1026                         die(_("cannot deflate request; zlib end error %d"), ret);
1027
1028                 gzip_size = stream.total_out;
1029
1030                 headers = curl_slist_append(headers, "Content-Encoding: gzip");
1031                 curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, gzip_body);
1032                 curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDSIZE_LARGE, xcurl_off_t(gzip_size));
1033
1034                 if (options.verbosity > 1) {
1035                         fprintf(stderr, "POST %s (gzip %lu to %lu bytes)\n",
1036                                 rpc->service_name,
1037                                 (unsigned long)rpc->len, (unsigned long)gzip_size);
1038                         fflush(stderr);
1039                 }
1040         } else {
1041                 /* We know the complete request size in advance, use the
1042                  * more normal Content-Length approach.
1043                  */
1044                 curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, rpc->buf);
1045                 curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDSIZE_LARGE, xcurl_off_t(rpc->len));
1046                 if (options.verbosity > 1) {
1047                         fprintf(stderr, "POST %s (%lu bytes)\n",
1048                                 rpc->service_name, (unsigned long)rpc->len);
1049                         fflush(stderr);
1050                 }
1051         }
1052
1053         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
1054         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, rpc_in);
1055         rpc_in_data.rpc = rpc;
1056         rpc_in_data.slot = slot;
1057         rpc_in_data.check_pktline = stateless_connect;
1058         memset(&rpc_in_data.pktline_state, 0, sizeof(rpc_in_data.pktline_state));
1059         curl_easy_setopt(slot->curl, CURLOPT_WRITEDATA, &rpc_in_data);
1060         curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
1061
1062
1063         rpc->any_written = 0;
1064         err = run_slot(slot, NULL);
1065         if (err == HTTP_REAUTH && !large_request) {
1066                 credential_fill(&http_auth, 0);
1067                 curl_slist_free_all(headers);
1068                 goto retry;
1069         }
1070         if (err != HTTP_OK)
1071                 err = -1;
1072
1073         if (!rpc->any_written)
1074                 err = -1;
1075
1076         if (rpc_in_data.pktline_state.len_filled)
1077                 err = error(_("%d bytes of length header were received"), rpc_in_data.pktline_state.len_filled);
1078         if (rpc_in_data.pktline_state.remaining)
1079                 err = error(_("%d bytes of body are still expected"), rpc_in_data.pktline_state.remaining);
1080
1081         if (stateless_connect)
1082                 packet_response_end(rpc->in);
1083
1084         curl_slist_free_all(headers);
1085         free(gzip_body);
1086         return err;
1087 }
1088
1089 static int rpc_service(struct rpc_state *rpc, struct discovery *heads,
1090                        const char **client_argv, const struct strbuf *preamble,
1091                        struct strbuf *rpc_result)
1092 {
1093         const char *svc = rpc->service_name;
1094         struct strbuf buf = STRBUF_INIT;
1095         struct child_process client = CHILD_PROCESS_INIT;
1096         int err = 0;
1097
1098         client.in = -1;
1099         client.out = -1;
1100         client.git_cmd = 1;
1101         strvec_pushv(&client.args, client_argv);
1102         if (start_command(&client))
1103                 exit(1);
1104         write_or_die(client.in, preamble->buf, preamble->len);
1105         if (heads)
1106                 write_or_die(client.in, heads->buf, heads->len);
1107
1108         rpc->alloc = http_post_buffer;
1109         rpc->buf = xmalloc(rpc->alloc);
1110         rpc->in = client.in;
1111         rpc->out = client.out;
1112
1113         strbuf_addf(&buf, "%s%s", url.buf, svc);
1114         rpc->service_url = strbuf_detach(&buf, NULL);
1115
1116         rpc->hdr_accept_language = xstrdup_or_null(http_get_accept_language_header());
1117
1118         strbuf_addf(&buf, "Content-Type: application/x-%s-request", svc);
1119         rpc->hdr_content_type = strbuf_detach(&buf, NULL);
1120
1121         strbuf_addf(&buf, "Accept: application/x-%s-result", svc);
1122         rpc->hdr_accept = strbuf_detach(&buf, NULL);
1123
1124         if (get_protocol_http_header(heads->version, &buf))
1125                 rpc->protocol_header = strbuf_detach(&buf, NULL);
1126         else
1127                 rpc->protocol_header = NULL;
1128
1129         while (!err) {
1130                 int n = packet_read(rpc->out, rpc->buf, rpc->alloc, 0);
1131                 if (!n)
1132                         break;
1133                 rpc->pos = 0;
1134                 rpc->len = n;
1135                 err |= post_rpc(rpc, 0, 0);
1136         }
1137
1138         close(client.in);
1139         client.in = -1;
1140         if (!err) {
1141                 strbuf_read(rpc_result, client.out, 0);
1142         } else {
1143                 char buf[4096];
1144                 for (;;)
1145                         if (xread(client.out, buf, sizeof(buf)) <= 0)
1146                                 break;
1147         }
1148
1149         close(client.out);
1150         client.out = -1;
1151
1152         err |= finish_command(&client);
1153         free(rpc->service_url);
1154         free(rpc->hdr_content_type);
1155         free(rpc->hdr_accept);
1156         free(rpc->hdr_accept_language);
1157         free(rpc->protocol_header);
1158         free(rpc->buf);
1159         strbuf_release(&buf);
1160         return err;
1161 }
1162
1163 static int fetch_dumb(int nr_heads, struct ref **to_fetch)
1164 {
1165         struct walker *walker;
1166         char **targets;
1167         int ret, i;
1168
1169         ALLOC_ARRAY(targets, nr_heads);
1170         if (options.depth || options.deepen_since)
1171                 die(_("dumb http transport does not support shallow capabilities"));
1172         for (i = 0; i < nr_heads; i++)
1173                 targets[i] = xstrdup(oid_to_hex(&to_fetch[i]->old_oid));
1174
1175         walker = get_http_walker(url.buf);
1176         walker->get_verbosely = options.verbosity >= 3;
1177         walker->get_progress = options.progress;
1178         walker->get_recover = 0;
1179         ret = walker_fetch(walker, nr_heads, targets, NULL, NULL);
1180         walker_free(walker);
1181
1182         for (i = 0; i < nr_heads; i++)
1183                 free(targets[i]);
1184         free(targets);
1185
1186         return ret ? error(_("fetch failed.")) : 0;
1187 }
1188
1189 static int fetch_git(struct discovery *heads,
1190         int nr_heads, struct ref **to_fetch)
1191 {
1192         struct rpc_state rpc = RPC_STATE_INIT;
1193         struct strbuf preamble = STRBUF_INIT;
1194         int i, err;
1195         struct strvec args = STRVEC_INIT;
1196         struct strbuf rpc_result = STRBUF_INIT;
1197
1198         strvec_pushl(&args, "fetch-pack", "--stateless-rpc",
1199                      "--stdin", "--lock-pack", NULL);
1200         if (options.followtags)
1201                 strvec_push(&args, "--include-tag");
1202         if (options.thin)
1203                 strvec_push(&args, "--thin");
1204         if (options.verbosity >= 3)
1205                 strvec_pushl(&args, "-v", "-v", NULL);
1206         if (options.check_self_contained_and_connected)
1207                 strvec_push(&args, "--check-self-contained-and-connected");
1208         if (options.cloning)
1209                 strvec_push(&args, "--cloning");
1210         if (options.update_shallow)
1211                 strvec_push(&args, "--update-shallow");
1212         if (!options.progress)
1213                 strvec_push(&args, "--no-progress");
1214         if (options.depth)
1215                 strvec_pushf(&args, "--depth=%lu", options.depth);
1216         if (options.deepen_since)
1217                 strvec_pushf(&args, "--shallow-since=%s", options.deepen_since);
1218         for (i = 0; i < options.deepen_not.nr; i++)
1219                 strvec_pushf(&args, "--shallow-exclude=%s",
1220                              options.deepen_not.items[i].string);
1221         if (options.deepen_relative && options.depth)
1222                 strvec_push(&args, "--deepen-relative");
1223         if (options.from_promisor)
1224                 strvec_push(&args, "--from-promisor");
1225         if (options.refetch)
1226                 strvec_push(&args, "--refetch");
1227         if (options.filter)
1228                 strvec_pushf(&args, "--filter=%s", options.filter);
1229         strvec_push(&args, url.buf);
1230
1231         for (i = 0; i < nr_heads; i++) {
1232                 struct ref *ref = to_fetch[i];
1233                 if (!*ref->name)
1234                         die(_("cannot fetch by sha1 over smart http"));
1235                 packet_buf_write(&preamble, "%s %s\n",
1236                                  oid_to_hex(&ref->old_oid), ref->name);
1237         }
1238         packet_buf_flush(&preamble);
1239
1240         memset(&rpc, 0, sizeof(rpc));
1241         rpc.service_name = "git-upload-pack",
1242         rpc.gzip_request = 1;
1243
1244         err = rpc_service(&rpc, heads, args.v, &preamble, &rpc_result);
1245         if (rpc_result.len)
1246                 write_or_die(1, rpc_result.buf, rpc_result.len);
1247         strbuf_release(&rpc_result);
1248         strbuf_release(&preamble);
1249         strvec_clear(&args);
1250         return err;
1251 }
1252
1253 static int fetch(int nr_heads, struct ref **to_fetch)
1254 {
1255         struct discovery *d = discover_refs("git-upload-pack", 0);
1256         if (d->proto_git)
1257                 return fetch_git(d, nr_heads, to_fetch);
1258         else
1259                 return fetch_dumb(nr_heads, to_fetch);
1260 }
1261
1262 static void parse_fetch(struct strbuf *buf)
1263 {
1264         struct ref **to_fetch = NULL;
1265         struct ref *list_head = NULL;
1266         struct ref **list = &list_head;
1267         int alloc_heads = 0, nr_heads = 0;
1268
1269         do {
1270                 const char *p;
1271                 if (skip_prefix(buf->buf, "fetch ", &p)) {
1272                         const char *name;
1273                         struct ref *ref;
1274                         struct object_id old_oid;
1275                         const char *q;
1276
1277                         if (parse_oid_hex(p, &old_oid, &q))
1278                                 die(_("protocol error: expected sha/ref, got '%s'"), p);
1279                         if (*q == ' ')
1280                                 name = q + 1;
1281                         else if (!*q)
1282                                 name = "";
1283                         else
1284                                 die(_("protocol error: expected sha/ref, got '%s'"), p);
1285
1286                         ref = alloc_ref(name);
1287                         oidcpy(&ref->old_oid, &old_oid);
1288
1289                         *list = ref;
1290                         list = &ref->next;
1291
1292                         ALLOC_GROW(to_fetch, nr_heads + 1, alloc_heads);
1293                         to_fetch[nr_heads++] = ref;
1294                 }
1295                 else
1296                         die(_("http transport does not support %s"), buf->buf);
1297
1298                 strbuf_reset(buf);
1299                 if (strbuf_getline_lf(buf, stdin) == EOF)
1300                         return;
1301                 if (!*buf->buf)
1302                         break;
1303         } while (1);
1304
1305         if (fetch(nr_heads, to_fetch))
1306                 exit(128); /* error already reported */
1307         free_refs(list_head);
1308         free(to_fetch);
1309
1310         printf("\n");
1311         fflush(stdout);
1312         strbuf_reset(buf);
1313 }
1314
1315 static void parse_get(const char *arg)
1316 {
1317         struct strbuf url = STRBUF_INIT;
1318         struct strbuf path = STRBUF_INIT;
1319         const char *space;
1320
1321         space = strchr(arg, ' ');
1322
1323         if (!space)
1324                 die(_("protocol error: expected '<url> <path>', missing space"));
1325
1326         strbuf_add(&url, arg, space - arg);
1327         strbuf_addstr(&path, space + 1);
1328
1329         if (http_get_file(url.buf, path.buf, NULL))
1330                 die(_("failed to download file at URL '%s'"), url.buf);
1331
1332         strbuf_release(&url);
1333         strbuf_release(&path);
1334         printf("\n");
1335         fflush(stdout);
1336 }
1337
1338 static int push_dav(int nr_spec, const char **specs)
1339 {
1340         struct child_process child = CHILD_PROCESS_INIT;
1341         size_t i;
1342
1343         child.git_cmd = 1;
1344         strvec_push(&child.args, "http-push");
1345         strvec_push(&child.args, "--helper-status");
1346         if (options.dry_run)
1347                 strvec_push(&child.args, "--dry-run");
1348         if (options.verbosity > 1)
1349                 strvec_push(&child.args, "--verbose");
1350         strvec_push(&child.args, url.buf);
1351         for (i = 0; i < nr_spec; i++)
1352                 strvec_push(&child.args, specs[i]);
1353
1354         if (run_command(&child))
1355                 die(_("git-http-push failed"));
1356         return 0;
1357 }
1358
1359 static int push_git(struct discovery *heads, int nr_spec, const char **specs)
1360 {
1361         struct rpc_state rpc = RPC_STATE_INIT;
1362         int i, err;
1363         struct strvec args;
1364         struct string_list_item *cas_option;
1365         struct strbuf preamble = STRBUF_INIT;
1366         struct strbuf rpc_result = STRBUF_INIT;
1367
1368         strvec_init(&args);
1369         strvec_pushl(&args, "send-pack", "--stateless-rpc", "--helper-status",
1370                      NULL);
1371
1372         if (options.thin)
1373                 strvec_push(&args, "--thin");
1374         if (options.dry_run)
1375                 strvec_push(&args, "--dry-run");
1376         if (options.push_cert == SEND_PACK_PUSH_CERT_ALWAYS)
1377                 strvec_push(&args, "--signed=yes");
1378         else if (options.push_cert == SEND_PACK_PUSH_CERT_IF_ASKED)
1379                 strvec_push(&args, "--signed=if-asked");
1380         if (options.atomic)
1381                 strvec_push(&args, "--atomic");
1382         if (options.verbosity == 0)
1383                 strvec_push(&args, "--quiet");
1384         else if (options.verbosity > 1)
1385                 strvec_push(&args, "--verbose");
1386         for (i = 0; i < options.push_options.nr; i++)
1387                 strvec_pushf(&args, "--push-option=%s",
1388                              options.push_options.items[i].string);
1389         strvec_push(&args, options.progress ? "--progress" : "--no-progress");
1390         for_each_string_list_item(cas_option, &cas_options)
1391                 strvec_push(&args, cas_option->string);
1392         strvec_push(&args, url.buf);
1393
1394         if (options.force_if_includes)
1395                 strvec_push(&args, "--force-if-includes");
1396
1397         strvec_push(&args, "--stdin");
1398         for (i = 0; i < nr_spec; i++)
1399                 packet_buf_write(&preamble, "%s\n", specs[i]);
1400         packet_buf_flush(&preamble);
1401
1402         memset(&rpc, 0, sizeof(rpc));
1403         rpc.service_name = "git-receive-pack",
1404
1405         err = rpc_service(&rpc, heads, args.v, &preamble, &rpc_result);
1406         if (rpc_result.len)
1407                 write_or_die(1, rpc_result.buf, rpc_result.len);
1408         strbuf_release(&rpc_result);
1409         strbuf_release(&preamble);
1410         strvec_clear(&args);
1411         return err;
1412 }
1413
1414 static int push(int nr_spec, const char **specs)
1415 {
1416         struct discovery *heads = discover_refs("git-receive-pack", 1);
1417         int ret;
1418
1419         if (heads->proto_git)
1420                 ret = push_git(heads, nr_spec, specs);
1421         else
1422                 ret = push_dav(nr_spec, specs);
1423         free_discovery(heads);
1424         return ret;
1425 }
1426
1427 static void parse_push(struct strbuf *buf)
1428 {
1429         struct strvec specs = STRVEC_INIT;
1430         int ret;
1431
1432         do {
1433                 const char *arg;
1434                 if (skip_prefix(buf->buf, "push ", &arg))
1435                         strvec_push(&specs, arg);
1436                 else
1437                         die(_("http transport does not support %s"), buf->buf);
1438
1439                 strbuf_reset(buf);
1440                 if (strbuf_getline_lf(buf, stdin) == EOF)
1441                         goto free_specs;
1442                 if (!*buf->buf)
1443                         break;
1444         } while (1);
1445
1446         ret = push(specs.nr, specs.v);
1447         printf("\n");
1448         fflush(stdout);
1449
1450         if (ret)
1451                 exit(128); /* error already reported */
1452
1453 free_specs:
1454         strvec_clear(&specs);
1455 }
1456
1457 static int stateless_connect(const char *service_name)
1458 {
1459         struct discovery *discover;
1460         struct rpc_state rpc = RPC_STATE_INIT;
1461         struct strbuf buf = STRBUF_INIT;
1462         const char *accept_language;
1463
1464         /*
1465          * Run the info/refs request and see if the server supports protocol
1466          * v2.  If and only if the server supports v2 can we successfully
1467          * establish a stateless connection, otherwise we need to tell the
1468          * client to fallback to using other transport helper functions to
1469          * complete their request.
1470          *
1471          * The "git-upload-archive" service is a read-only operation. Fallback
1472          * to use "git-upload-pack" service to discover protocol version.
1473          */
1474         if (!strcmp(service_name, "git-upload-archive"))
1475                 discover = discover_refs("git-upload-pack", 0);
1476         else
1477                 discover = discover_refs(service_name, 0);
1478         if (discover->version != protocol_v2) {
1479                 printf("fallback\n");
1480                 fflush(stdout);
1481                 return -1;
1482         } else {
1483                 /* Stateless Connection established */
1484                 printf("\n");
1485                 fflush(stdout);
1486         }
1487         accept_language = http_get_accept_language_header();
1488         if (accept_language)
1489                 rpc.hdr_accept_language = xstrfmt("%s", accept_language);
1490
1491         rpc.service_name = service_name;
1492         rpc.service_url = xstrfmt("%s%s", url.buf, rpc.service_name);
1493         rpc.hdr_content_type = xstrfmt("Content-Type: application/x-%s-request", rpc.service_name);
1494         rpc.hdr_accept = xstrfmt("Accept: application/x-%s-result", rpc.service_name);
1495         if (get_protocol_http_header(discover->version, &buf)) {
1496                 rpc.protocol_header = strbuf_detach(&buf, NULL);
1497         } else {
1498                 rpc.protocol_header = NULL;
1499                 strbuf_release(&buf);
1500         }
1501         rpc.buf = xmalloc(http_post_buffer);
1502         rpc.alloc = http_post_buffer;
1503         rpc.len = 0;
1504         rpc.pos = 0;
1505         rpc.in = 1;
1506         rpc.out = 0;
1507         rpc.any_written = 0;
1508         rpc.gzip_request = 1;
1509         rpc.initial_buffer = 0;
1510         rpc.write_line_lengths = 1;
1511         rpc.flush_read_but_not_sent = 0;
1512
1513         /*
1514          * Dump the capability listing that we got from the server earlier
1515          * during the info/refs request. This does not work with the
1516          * "git-upload-archive" service.
1517          */
1518         if (strcmp(service_name, "git-upload-archive"))
1519                 write_or_die(rpc.in, discover->buf, discover->len);
1520
1521         /* Until we see EOF keep sending POSTs */
1522         while (1) {
1523                 size_t avail;
1524                 enum packet_read_status status;
1525
1526                 if (!rpc_read_from_out(&rpc, PACKET_READ_GENTLE_ON_EOF, &avail,
1527                                        &status))
1528                         BUG("The entire rpc->buf should be larger than LARGE_PACKET_MAX");
1529                 if (status == PACKET_READ_EOF)
1530                         break;
1531                 if (post_rpc(&rpc, 1, status == PACKET_READ_FLUSH))
1532                         /* We would have an err here */
1533                         break;
1534                 /* Reset the buffer for next request */
1535                 rpc.len = 0;
1536         }
1537
1538         free(rpc.service_url);
1539         free(rpc.hdr_content_type);
1540         free(rpc.hdr_accept);
1541         free(rpc.hdr_accept_language);
1542         free(rpc.protocol_header);
1543         free(rpc.buf);
1544         strbuf_release(&buf);
1545
1546         return 0;
1547 }
1548
1549 int cmd_main(int argc, const char **argv)
1550 {
1551         struct strbuf buf = STRBUF_INIT;
1552         int nongit;
1553         int ret = 1;
1554
1555         setup_git_directory_gently(&nongit);
1556         if (argc < 2) {
1557                 error(_("remote-curl: usage: git remote-curl <remote> [<url>]"));
1558                 goto cleanup;
1559         }
1560
1561         options.verbosity = 1;
1562         options.progress = !!isatty(2);
1563         options.thin = 1;
1564         string_list_init_dup(&options.deepen_not);
1565         string_list_init_dup(&options.push_options);
1566
1567         /*
1568          * Just report "remote-curl" here (folding all the various aliases
1569          * ("git-remote-http", "git-remote-https", and etc.) here since they
1570          * are all just copies of the same actual executable.
1571          */
1572         trace2_cmd_name("remote-curl");
1573
1574         remote = remote_get(argv[1]);
1575
1576         if (argc > 2) {
1577                 end_url_with_slash(&url, argv[2]);
1578         } else {
1579                 end_url_with_slash(&url, remote->url.v[0]);
1580         }
1581
1582         http_init(remote, url.buf, 0);
1583
1584         do {
1585                 const char *arg;
1586
1587                 if (strbuf_getline_lf(&buf, stdin) == EOF) {
1588                         if (ferror(stdin))
1589                                 error(_("remote-curl: error reading command stream from git"));
1590                         goto cleanup;
1591                 }
1592                 if (buf.len == 0)
1593                         break;
1594                 if (starts_with(buf.buf, "fetch ")) {
1595                         if (nongit) {
1596                                 setup_git_directory_gently(&nongit);
1597                                 if (nongit)
1598                                         die(_("remote-curl: fetch attempted without a local repo"));
1599                         }
1600                         parse_fetch(&buf);
1601
1602                 } else if (!strcmp(buf.buf, "list") || starts_with(buf.buf, "list ")) {
1603                         int for_push = !!strstr(buf.buf + 4, "for-push");
1604                         output_refs(get_refs(for_push));
1605
1606                 } else if (starts_with(buf.buf, "push ")) {
1607                         parse_push(&buf);
1608
1609                 } else if (skip_prefix(buf.buf, "option ", &arg)) {
1610                         const char *value = strchrnul(arg, ' ');
1611                         size_t arglen = value - arg;
1612                         int result;
1613
1614                         if (*value)
1615                                 value++; /* skip over SP */
1616                         else
1617                                 value = "true";
1618
1619                         result = set_option(arg, arglen, value);
1620                         if (!result)
1621                                 printf("ok\n");
1622                         else if (result < 0)
1623                                 printf("error invalid value\n");
1624                         else
1625                                 printf("unsupported\n");
1626                         fflush(stdout);
1627
1628                 } else if (skip_prefix(buf.buf, "get ", &arg)) {
1629                         parse_get(arg);
1630                         fflush(stdout);
1631
1632                 } else if (!strcmp(buf.buf, "capabilities")) {
1633                         printf("stateless-connect\n");
1634                         printf("fetch\n");
1635                         printf("get\n");
1636                         printf("option\n");
1637                         printf("push\n");
1638                         printf("check-connectivity\n");
1639                         printf("object-format\n");
1640                         printf("\n");
1641                         fflush(stdout);
1642                 } else if (skip_prefix(buf.buf, "stateless-connect ", &arg)) {
1643                         if (!stateless_connect(arg))
1644                                 break;
1645                 } else {
1646                         error(_("remote-curl: unknown command '%s' from git"), buf.buf);
1647                         goto cleanup;
1648                 }
1649                 strbuf_reset(&buf);
1650         } while (1);
1651
1652         http_cleanup();
1653         ret = 0;
1654 cleanup:
1655         strbuf_release(&buf);
1656
1657         return ret;
1658 }