transport-helper.c

   1 #include "cache.h"
   2 #include "transport.h"
   3 #include "quote.h"
   4 #include "run-command.h"
   5 #include "commit.h"
   6 #include "diff.h"
   7 #include "revision.h"
   8 #include "quote.h"
   9 #include "remote.h"
  10
  11 static int debug;
  12
  13 struct helper_data
  14 {
  15         const char *name;
  16         struct child_process *helper;
  17         FILE *out;
  18         unsigned fetch : 1,
  19                 import : 1,
  20                 option : 1,
  21                 push : 1;
  22         /* These go from remote name (as in "list") to private name */
  23         struct refspec *refspecs;
  24         int refspec_nr;
  25         /* Transport options for fetch-pack/send-pack (should one of
  26          * those be invoked).
  27          */
  28         struct git_transport_options transport_options;
  29 };
  30
  31 static void sendline(struct helper_data *helper, struct strbuf *buffer)
  32 {
  33         if (debug)
  34                 fprintf(stderr, "Debug: Remote helper: -> %s", buffer->buf);
  35         if (write_in_full(helper->helper->in, buffer->buf, buffer->len)
  36                 != buffer->len)
  37                 die_errno("Full write to remote helper failed");
  38 }
  39
  40 static int recvline(struct helper_data *helper, struct strbuf *buffer)
  41 {
  42         strbuf_reset(buffer);
  43         if (debug)
  44                 fprintf(stderr, "Debug: Remote helper: Waiting...\n");
  45         if (strbuf_getline(buffer, helper->out, '\n') == EOF) {
  46                 if (debug)
  47                         fprintf(stderr, "Debug: Remote helper quit.\n");
  48                 exit(128);
  49         }
  50
  51         if (debug)
  52                 fprintf(stderr, "Debug: Remote helper: <- %s\n", buffer->buf);
  53         return 0;
  54 }
  55
  56 static void xchgline(struct helper_data *helper, struct strbuf *buffer)
  57 {
  58         sendline(helper, buffer);
  59         recvline(helper, buffer);
  60 }
  61
  62 static void write_constant(int fd, const char *str)
  63 {
  64         if (debug)
  65                 fprintf(stderr, "Debug: Remote helper: -> %s", str);
  66         if (write_in_full(fd, str, strlen(str)) != strlen(str))
  67                 die_errno("Full write to remote helper failed");
  68 }
  69
  70 const char *remove_ext_force(const char *url)
  71 {
  72         if (url) {
  73                 const char *colon = strchr(url, ':');
  74                 if (colon && colon[1] == ':')
  75                         return colon + 2;
  76         }
  77         return url;
  78 }
  79
  80 static struct child_process *get_helper(struct transport *transport)
  81 {
  82         struct helper_data *data = transport->data;
  83         struct strbuf buf = STRBUF_INIT;
  84         struct child_process *helper;
  85         const char **refspecs = NULL;
  86         int refspec_nr = 0;
  87         int refspec_alloc = 0;
  88         int duped;
  89
  90         if (data->helper)
  91                 return data->helper;
  92
  93         helper = xcalloc(1, sizeof(*helper));
  94         helper->in = -1;
  95         helper->out = -1;
  96         helper->err = 0;
  97         helper->argv = xcalloc(4, sizeof(*helper->argv));
  98         strbuf_addf(&buf, "remote-%s", data->name);
  99         helper->argv[0] = strbuf_detach(&buf, NULL);
 100         helper->argv[1] = transport->remote->name;
 101         helper->argv[2] = remove_ext_force(transport->url);
 102         helper->git_cmd = 1;
 103         if (start_command(helper))
 104                 die("Unable to run helper: git %s", helper->argv[0]);
 105         data->helper = helper;
 106
 107         /*
 108          * Open the output as FILE* so strbuf_getline() can be used.
 109          * Do this with duped fd because fclose() will close the fd,
 110          * and stuff like taking over will require the fd to remain.
 111          *
 112          */
 113         duped = dup(helper->out);
 114         if (duped < 0)
 115                 die_errno("Can't dup helper output fd");
 116         data->out = xfdopen(duped, "r");
 117
 118         write_constant(helper->in, "capabilities\n");
 119
 120         while (1) {
 121                 const char *capname;
 122                 int mandatory = 0;
 123                 recvline(data, &buf);
 124
 125                 if (!*buf.buf)
 126                         break;
 127
 128                 if (*buf.buf == '*') {
 129                         capname = buf.buf + 1;
 130                         mandatory = 1;
 131                 } else
 132                         capname = buf.buf;
 133
 134                 if (debug)
 135                         fprintf(stderr, "Debug: Got cap %s\n", capname);
 136                 if (!strcmp(capname, "fetch"))
 137                         data->fetch = 1;
 138                 else if (!strcmp(capname, "option"))
 139                         data->option = 1;
 140                 else if (!strcmp(capname, "push"))
 141                         data->push = 1;
 142                 else if (!strcmp(capname, "import"))
 143                         data->import = 1;
 144                 else if (!data->refspecs && !prefixcmp(capname, "refspec ")) {
 145                         ALLOC_GROW(refspecs,
 146                                    refspec_nr + 1,
 147                                    refspec_alloc);
 148                         refspecs[refspec_nr++] = strdup(buf.buf + strlen("refspec "));
 149                 } else if (mandatory) {
 150                         die("Unknown madatory capability %s. This remote "
 151                             "helper probably needs newer version of Git.\n",
 152                             capname);
 153                 }
 154         }
 155         if (refspecs) {
 156                 int i;
 157                 data->refspec_nr = refspec_nr;
 158                 data->refspecs = parse_fetch_refspec(refspec_nr, refspecs);
 159                 for (i = 0; i < refspec_nr; i++) {
 160                         free((char *)refspecs[i]);
 161                 }
 162                 free(refspecs);
 163         }
 164         strbuf_release(&buf);
 165         if (debug)
 166                 fprintf(stderr, "Debug: Capabilities complete.\n");
 167         return data->helper;
 168 }
 169
 170 static int disconnect_helper(struct transport *transport)
 171 {
 172         struct helper_data *data = transport->data;
 173         struct strbuf buf = STRBUF_INIT;
 174
 175         if (data->helper) {
 176                 if (debug)
 177                         fprintf(stderr, "Debug: Disconnecting.\n");
 178                 strbuf_addf(&buf, "\n");
 179                 sendline(data, &buf);
 180                 close(data->helper->in);
 181                 close(data->helper->out);
 182                 fclose(data->out);
 183                 finish_command(data->helper);
 184                 free((char *)data->helper->argv[0]);
 185                 free(data->helper->argv);
 186                 free(data->helper);
 187                 data->helper = NULL;
 188         }
 189         return 0;
 190 }
 191
 192 static const char *unsupported_options[] = {
 193         TRANS_OPT_UPLOADPACK,
 194         TRANS_OPT_RECEIVEPACK,
 195         TRANS_OPT_THIN,
 196         TRANS_OPT_KEEP
 197         };
 198 static const char *boolean_options[] = {
 199         TRANS_OPT_THIN,
 200         TRANS_OPT_KEEP,
 201         TRANS_OPT_FOLLOWTAGS
 202         };
 203
 204 static int set_helper_option(struct transport *transport,
 205                           const char *name, const char *value)
 206 {
 207         struct helper_data *data = transport->data;
 208         struct strbuf buf = STRBUF_INIT;
 209         int i, ret, is_bool = 0;
 210
 211         get_helper(transport);
 212
 213         if (!data->option)
 214                 return 1;
 215
 216         for (i = 0; i < ARRAY_SIZE(unsupported_options); i++) {
 217                 if (!strcmp(name, unsupported_options[i]))
 218                         return 1;
 219         }
 220
 221         for (i = 0; i < ARRAY_SIZE(boolean_options); i++) {
 222                 if (!strcmp(name, boolean_options[i])) {
 223                         is_bool = 1;
 224                         break;
 225                 }
 226         }
 227
 228         strbuf_addf(&buf, "option %s ", name);
 229         if (is_bool)
 230                 strbuf_addstr(&buf, value ? "true" : "false");
 231         else
 232                 quote_c_style(value, &buf, NULL, 0);
 233         strbuf_addch(&buf, '\n');
 234
 235         xchgline(data, &buf);
 236
 237         if (!strcmp(buf.buf, "ok"))
 238                 ret = 0;
 239         else if (!prefixcmp(buf.buf, "error")) {
 240                 ret = -1;
 241         } else if (!strcmp(buf.buf, "unsupported"))
 242                 ret = 1;
 243         else {
 244                 warning("%s unexpectedly said: '%s'", data->name, buf.buf);
 245                 ret = 1;
 246         }
 247         strbuf_release(&buf);
 248         return ret;
 249 }
 250
 251 static void standard_options(struct transport *t)
 252 {
 253         char buf[16];
 254         int n;
 255         int v = t->verbose;
 256         int no_progress = v < 0 || (!t->progress && !isatty(1));
 257
 258         set_helper_option(t, "progress", !no_progress ? "true" : "false");
 259
 260         n = snprintf(buf, sizeof(buf), "%d", v + 1);
 261         if (n >= sizeof(buf))
 262                 die("impossibly large verbosity value");
 263         set_helper_option(t, "verbosity", buf);
 264 }
 265
 266 static int release_helper(struct transport *transport)
 267 {
 268         struct helper_data *data = transport->data;
 269         free_refspec(data->refspec_nr, data->refspecs);
 270         data->refspecs = NULL;
 271         disconnect_helper(transport);
 272         free(transport->data);
 273         return 0;
 274 }
 275
 276 static int fetch_with_fetch(struct transport *transport,
 277                             int nr_heads, struct ref **to_fetch)
 278 {
 279         struct helper_data *data = transport->data;
 280         int i;
 281         struct strbuf buf = STRBUF_INIT;
 282
 283         standard_options(transport);
 284
 285         for (i = 0; i < nr_heads; i++) {
 286                 const struct ref *posn = to_fetch[i];
 287                 if (posn->status & REF_STATUS_UPTODATE)
 288                         continue;
 289
 290                 strbuf_addf(&buf, "fetch %s %s\n",
 291                             sha1_to_hex(posn->old_sha1), posn->name);
 292         }
 293
 294         strbuf_addch(&buf, '\n');
 295         sendline(data, &buf);
 296
 297         while (1) {
 298                 recvline(data, &buf);
 299
 300                 if (!prefixcmp(buf.buf, "lock ")) {
 301                         const char *name = buf.buf + 5;
 302                         if (transport->pack_lockfile)
 303                                 warning("%s also locked %s", data->name, name);
 304                         else
 305                                 transport->pack_lockfile = xstrdup(name);
 306                 }
 307                 else if (!buf.len)
 308                         break;
 309                 else
 310                         warning("%s unexpectedly said: '%s'", data->name, buf.buf);
 311         }
 312         strbuf_release(&buf);
 313         return 0;
 314 }
 315
 316 static int get_importer(struct transport *transport, struct child_process *fastimport)
 317 {
 318         struct child_process *helper = get_helper(transport);
 319         memset(fastimport, 0, sizeof(*fastimport));
 320         fastimport->in = helper->out;
 321         fastimport->argv = xcalloc(5, sizeof(*fastimport->argv));
 322         fastimport->argv[0] = "fast-import";
 323         fastimport->argv[1] = "--quiet";
 324
 325         fastimport->git_cmd = 1;
 326         return start_command(fastimport);
 327 }
 328
 329 static int fetch_with_import(struct transport *transport,
 330                              int nr_heads, struct ref **to_fetch)
 331 {
 332         struct child_process fastimport;
 333         struct helper_data *data = transport->data;
 334         int i;
 335         struct ref *posn;
 336         struct strbuf buf = STRBUF_INIT;
 337
 338         get_helper(transport);
 339
 340         if (get_importer(transport, &fastimport))
 341                 die("Couldn't run fast-import");
 342
 343         for (i = 0; i < nr_heads; i++) {
 344                 posn = to_fetch[i];
 345                 if (posn->status & REF_STATUS_UPTODATE)
 346                         continue;
 347
 348                 strbuf_addf(&buf, "import %s\n", posn->name);
 349                 sendline(data, &buf);
 350                 strbuf_reset(&buf);
 351         }
 352         disconnect_helper(transport);
 353         finish_command(&fastimport);
 354         free(fastimport.argv);
 355         fastimport.argv = NULL;
 356
 357         for (i = 0; i < nr_heads; i++) {
 358                 char *private;
 359                 posn = to_fetch[i];
 360                 if (posn->status & REF_STATUS_UPTODATE)
 361                         continue;
 362                 if (data->refspecs)
 363                         private = apply_refspecs(data->refspecs, data->refspec_nr, posn->name);
 364                 else
 365                         private = strdup(posn->name);
 366                 read_ref(private, posn->old_sha1);
 367                 free(private);
 368         }
 369         strbuf_release(&buf);
 370         return 0;
 371 }
 372
 373 static int fetch(struct transport *transport,
 374                  int nr_heads, struct ref **to_fetch)
 375 {
 376         struct helper_data *data = transport->data;
 377         int i, count;
 378
 379         count = 0;
 380         for (i = 0; i < nr_heads; i++)
 381                 if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
 382                         count++;
 383
 384         if (!count)
 385                 return 0;
 386
 387         if (data->fetch)
 388                 return fetch_with_fetch(transport, nr_heads, to_fetch);
 389
 390         if (data->import)
 391                 return fetch_with_import(transport, nr_heads, to_fetch);
 392
 393         return -1;
 394 }
 395
 396 static int push_refs(struct transport *transport,
 397                 struct ref *remote_refs, int flags)
 398 {
 399         int force_all = flags & TRANSPORT_PUSH_FORCE;
 400         int mirror = flags & TRANSPORT_PUSH_MIRROR;
 401         struct helper_data *data = transport->data;
 402         struct strbuf buf = STRBUF_INIT;
 403         struct child_process *helper;
 404         struct ref *ref;
 405
 406         if (!remote_refs)
 407                 return 0;
 408
 409         helper = get_helper(transport);
 410         if (!data->push)
 411                 return 1;
 412
 413         for (ref = remote_refs; ref; ref = ref->next) {
 414                 if (ref->peer_ref)
 415                         hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
 416                 else if (!mirror)
 417                         continue;
 418
 419                 ref->deletion = is_null_sha1(ref->new_sha1);
 420                 if (!ref->deletion &&
 421                         !hashcmp(ref->old_sha1, ref->new_sha1)) {
 422                         ref->status = REF_STATUS_UPTODATE;
 423                         continue;
 424                 }
 425
 426                 if (force_all)
 427                         ref->force = 1;
 428
 429                 strbuf_addstr(&buf, "push ");
 430                 if (!ref->deletion) {
 431                         if (ref->force)
 432                                 strbuf_addch(&buf, '+');
 433                         if (ref->peer_ref)
 434                                 strbuf_addstr(&buf, ref->peer_ref->name);
 435                         else
 436                                 strbuf_addstr(&buf, sha1_to_hex(ref->new_sha1));
 437                 }
 438                 strbuf_addch(&buf, ':');
 439                 strbuf_addstr(&buf, ref->name);
 440                 strbuf_addch(&buf, '\n');
 441         }
 442         if (buf.len == 0)
 443                 return 0;
 444
 445         transport->verbose = flags & TRANSPORT_PUSH_VERBOSE ? 1 : 0;
 446         standard_options(transport);
 447
 448         if (flags & TRANSPORT_PUSH_DRY_RUN) {
 449                 if (set_helper_option(transport, "dry-run", "true") != 0)
 450                         die("helper %s does not support dry-run", data->name);
 451         }
 452
 453         strbuf_addch(&buf, '\n');
 454         sendline(data, &buf);
 455
 456         ref = remote_refs;
 457         while (1) {
 458                 char *refname, *msg;
 459                 int status;
 460
 461                 recvline(data, &buf);
 462                 if (!buf.len)
 463                         break;
 464
 465                 if (!prefixcmp(buf.buf, "ok ")) {
 466                         status = REF_STATUS_OK;
 467                         refname = buf.buf + 3;
 468                 } else if (!prefixcmp(buf.buf, "error ")) {
 469                         status = REF_STATUS_REMOTE_REJECT;
 470                         refname = buf.buf + 6;
 471                 } else
 472                         die("expected ok/error, helper said '%s'\n", buf.buf);
 473
 474                 msg = strchr(refname, ' ');
 475                 if (msg) {
 476                         struct strbuf msg_buf = STRBUF_INIT;
 477                         const char *end;
 478
 479                         *msg++ = '\0';
 480                         if (!unquote_c_style(&msg_buf, msg, &end))
 481                                 msg = strbuf_detach(&msg_buf, NULL);
 482                         else
 483                                 msg = xstrdup(msg);
 484                         strbuf_release(&msg_buf);
 485
 486                         if (!strcmp(msg, "no match")) {
 487                                 status = REF_STATUS_NONE;
 488                                 free(msg);
 489                                 msg = NULL;
 490                         }
 491                         else if (!strcmp(msg, "up to date")) {
 492                                 status = REF_STATUS_UPTODATE;
 493                                 free(msg);
 494                                 msg = NULL;
 495                         }
 496                         else if (!strcmp(msg, "non-fast forward")) {
 497                                 status = REF_STATUS_REJECT_NONFASTFORWARD;
 498                                 free(msg);
 499                                 msg = NULL;
 500                         }
 501                 }
 502
 503                 if (ref)
 504                         ref = find_ref_by_name(ref, refname);
 505                 if (!ref)
 506                         ref = find_ref_by_name(remote_refs, refname);
 507                 if (!ref) {
 508                         warning("helper reported unexpected status of %s", refname);
 509                         continue;
 510                 }
 511
 512                 ref->status = status;
 513                 ref->remote_status = msg;
 514         }
 515         strbuf_release(&buf);
 516         return 0;
 517 }
 518
 519 static int has_attribute(const char *attrs, const char *attr) {
 520         int len;
 521         if (!attrs)
 522                 return 0;
 523
 524         len = strlen(attr);
 525         for (;;) {
 526                 const char *space = strchrnul(attrs, ' ');
 527                 if (len == space - attrs && !strncmp(attrs, attr, len))
 528                         return 1;
 529                 if (!*space)
 530                         return 0;
 531                 attrs = space + 1;
 532         }
 533 }
 534
 535 static struct ref *get_refs_list(struct transport *transport, int for_push)
 536 {
 537         struct helper_data *data = transport->data;
 538         struct child_process *helper;
 539         struct ref *ret = NULL;
 540         struct ref **tail = &ret;
 541         struct ref *posn;
 542         struct strbuf buf = STRBUF_INIT;
 543
 544         helper = get_helper(transport);
 545
 546         if (data->push && for_push)
 547                 write_str_in_full(helper->in, "list for-push\n");
 548         else
 549                 write_str_in_full(helper->in, "list\n");
 550
 551         while (1) {
 552                 char *eov, *eon;
 553                 recvline(data, &buf);
 554
 555                 if (!*buf.buf)
 556                         break;
 557
 558                 eov = strchr(buf.buf, ' ');
 559                 if (!eov)
 560                         die("Malformed response in ref list: %s", buf.buf);
 561                 eon = strchr(eov + 1, ' ');
 562                 *eov = '\0';
 563                 if (eon)
 564                         *eon = '\0';
 565                 *tail = alloc_ref(eov + 1);
 566                 if (buf.buf[0] == '@')
 567                         (*tail)->symref = xstrdup(buf.buf + 1);
 568                 else if (buf.buf[0] != '?')
 569                         get_sha1_hex(buf.buf, (*tail)->old_sha1);
 570                 if (eon) {
 571                         if (has_attribute(eon + 1, "unchanged")) {
 572                                 (*tail)->status |= REF_STATUS_UPTODATE;
 573                                 read_ref((*tail)->name, (*tail)->old_sha1);
 574                         }
 575                 }
 576                 tail = &((*tail)->next);
 577         }
 578         if (debug)
 579                 fprintf(stderr, "Debug: Read ref listing.\n");
 580         strbuf_release(&buf);
 581
 582         for (posn = ret; posn; posn = posn->next)
 583                 resolve_remote_symref(posn, ret);
 584
 585         return ret;
 586 }
 587
 588 int transport_helper_init(struct transport *transport, const char *name)
 589 {
 590         struct helper_data *data = xcalloc(sizeof(*data), 1);
 591         data->name = name;
 592
 593         if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
 594                 debug = 1;
 595
 596         transport->data = data;
 597         transport->set_option = set_helper_option;
 598         transport->get_refs_list = get_refs_list;
 599         transport->fetch = fetch;
 600         transport->push_refs = push_refs;
 601         transport->disconnect = release_helper;
 602         transport->smart_options = &(data->transport_options);
 603         return 0;
 604 }