connect.c

   1 #include "git-compat-util.h"
   2 #include "cache.h"
   3 #include "pkt-line.h"
   4 #include "quote.h"
   5 #include "refs.h"
   6 #include "run-command.h"
   7 #include "remote.h"
   8 #include "connect.h"
   9 #include "url.h"
  10 #include "string-list.h"
  11 #include "sha1-array.h"
  12
  13 static char *server_capabilities;
  14 static const char *parse_feature_value(const char *, const char *, int *);
  15
  16 static int check_ref(const char *name, int len, unsigned int flags)
  17 {
  18         if (!flags)
  19                 return 1;
  20
  21         if (len < 5 || memcmp(name, "refs/", 5))
  22                 return 0;
  23
  24         /* Skip the "refs/" part */
  25         name += 5;
  26         len -= 5;
  27
  28         /* REF_NORMAL means that we don't want the magic fake tag refs */
  29         if ((flags & REF_NORMAL) && check_refname_format(name, 0))
  30                 return 0;
  31
  32         /* REF_HEADS means that we want regular branch heads */
  33         if ((flags & REF_HEADS) && !memcmp(name, "heads/", 6))
  34                 return 1;
  35
  36         /* REF_TAGS means that we want tags */
  37         if ((flags & REF_TAGS) && !memcmp(name, "tags/", 5))
  38                 return 1;
  39
  40         /* All type bits clear means that we are ok with anything */
  41         return !(flags & ~REF_NORMAL);
  42 }
  43
  44 int check_ref_type(const struct ref *ref, int flags)
  45 {
  46         return check_ref(ref->name, strlen(ref->name), flags);
  47 }
  48
  49 static void die_initial_contact(int got_at_least_one_head)
  50 {
  51         if (got_at_least_one_head)
  52                 die("The remote end hung up upon initial contact");
  53         else
  54                 die("Could not read from remote repository.\n\n"
  55                     "Please make sure you have the correct access rights\n"
  56                     "and the repository exists.");
  57 }
  58
  59 static void parse_one_symref_info(struct string_list *symref, const char *val, int len)
  60 {
  61         char *sym, *target;
  62         struct string_list_item *item;
  63
  64         if (!len)
  65                 return; /* just "symref" */
  66         /* e.g. "symref=HEAD:refs/heads/master" */
  67         sym = xmalloc(len + 1);
  68         memcpy(sym, val, len);
  69         sym[len] = '\0';
  70         target = strchr(sym, ':');
  71         if (!target)
  72                 /* just "symref=something" */
  73                 goto reject;
  74         *(target++) = '\0';
  75         if (check_refname_format(sym, REFNAME_ALLOW_ONELEVEL) ||
  76             check_refname_format(target, REFNAME_ALLOW_ONELEVEL))
  77                 /* "symref=bogus:pair */
  78                 goto reject;
  79         item = string_list_append(symref, sym);
  80         item->util = target;
  81         return;
  82 reject:
  83         free(sym);
  84         return;
  85 }
  86
  87 static void annotate_refs_with_symref_info(struct ref *ref)
  88 {
  89         struct string_list symref = STRING_LIST_INIT_DUP;
  90         const char *feature_list = server_capabilities;
  91
  92         while (feature_list) {
  93                 int len;
  94                 const char *val;
  95
  96                 val = parse_feature_value(feature_list, "symref", &len);
  97                 if (!val)
  98                         break;
  99                 parse_one_symref_info(&symref, val, len);
 100                 feature_list = val + 1;
 101         }
 102         sort_string_list(&symref);
 103
 104         for (; ref; ref = ref->next) {
 105                 struct string_list_item *item;
 106                 item = string_list_lookup(&symref, ref->name);
 107                 if (!item)
 108                         continue;
 109                 ref->symref = xstrdup((char *)item->util);
 110         }
 111         string_list_clear(&symref, 0);
 112 }
 113
 114 /*
 115  * Read all the refs from the other end
 116  */
 117 struct ref **get_remote_heads(int in, char *src_buf, size_t src_len,
 118                               struct ref **list, unsigned int flags,
 119                               struct sha1_array *extra_have,
 120                               struct sha1_array *shallow_points)
 121 {
 122         struct ref **orig_list = list;
 123         int got_at_least_one_head = 0;
 124
 125         *list = NULL;
 126         for (;;) {
 127                 struct ref *ref;
 128                 unsigned char old_sha1[20];
 129                 char *name;
 130                 int len, name_len;
 131                 char *buffer = packet_buffer;
 132                 const char *arg;
 133
 134                 len = packet_read(in, &src_buf, &src_len,
 135                                   packet_buffer, sizeof(packet_buffer),
 136                                   PACKET_READ_GENTLE_ON_EOF |
 137                                   PACKET_READ_CHOMP_NEWLINE);
 138                 if (len < 0)
 139                         die_initial_contact(got_at_least_one_head);
 140
 141                 if (!len)
 142                         break;
 143
 144                 if (len > 4 && skip_prefix(buffer, "ERR ", &arg))
 145                         die("remote error: %s", arg);
 146
 147                 if (len == 48 && skip_prefix(buffer, "shallow ", &arg)) {
 148                         if (get_sha1_hex(arg, old_sha1))
 149                                 die("protocol error: expected shallow sha-1, got '%s'", arg);
 150                         if (!shallow_points)
 151                                 die("repository on the other end cannot be shallow");
 152                         sha1_array_append(shallow_points, old_sha1);
 153                         continue;
 154                 }
 155
 156                 if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
 157                         die("protocol error: expected sha/ref, got '%s'", buffer);
 158                 name = buffer + 41;
 159
 160                 name_len = strlen(name);
 161                 if (len != name_len + 41) {
 162                         free(server_capabilities);
 163                         server_capabilities = xstrdup(name + name_len + 1);
 164                 }
 165
 166                 if (extra_have &&
 167                     name_len == 5 && !memcmp(".have", name, 5)) {
 168                         sha1_array_append(extra_have, old_sha1);
 169                         continue;
 170                 }
 171
 172                 if (!check_ref(name, name_len, flags))
 173                         continue;
 174                 ref = alloc_ref(buffer + 41);
 175                 hashcpy(ref->old_sha1, old_sha1);
 176                 *list = ref;
 177                 list = &ref->next;
 178                 got_at_least_one_head = 1;
 179         }
 180
 181         annotate_refs_with_symref_info(*orig_list);
 182
 183         return list;
 184 }
 185
 186 static const char *parse_feature_value(const char *feature_list, const char *feature, int *lenp)
 187 {
 188         int len;
 189
 190         if (!feature_list)
 191                 return NULL;
 192
 193         len = strlen(feature);
 194         while (*feature_list) {
 195                 const char *found = strstr(feature_list, feature);
 196                 if (!found)
 197                         return NULL;
 198                 if (feature_list == found || isspace(found[-1])) {
 199                         const char *value = found + len;
 200                         /* feature with no value (e.g., "thin-pack") */
 201                         if (!*value || isspace(*value)) {
 202                                 if (lenp)
 203                                         *lenp = 0;
 204                                 return value;
 205                         }
 206                         /* feature with a value (e.g., "agent=git/1.2.3") */
 207                         else if (*value == '=') {
 208                                 value++;
 209                                 if (lenp)
 210                                         *lenp = strcspn(value, " \t\n");
 211                                 return value;
 212                         }
 213                         /*
 214                          * otherwise we matched a substring of another feature;
 215                          * keep looking
 216                          */
 217                 }
 218                 feature_list = found + 1;
 219         }
 220         return NULL;
 221 }
 222
 223 int parse_feature_request(const char *feature_list, const char *feature)
 224 {
 225         return !!parse_feature_value(feature_list, feature, NULL);
 226 }
 227
 228 const char *server_feature_value(const char *feature, int *len)
 229 {
 230         return parse_feature_value(server_capabilities, feature, len);
 231 }
 232
 233 int server_supports(const char *feature)
 234 {
 235         return !!server_feature_value(feature, NULL);
 236 }
 237
 238 enum protocol {
 239         PROTO_LOCAL = 1,
 240         PROTO_FILE,
 241         PROTO_SSH,
 242         PROTO_GIT
 243 };
 244
 245 int url_is_local_not_ssh(const char *url)
 246 {
 247         const char *colon = strchr(url, ':');
 248         const char *slash = strchr(url, '/');
 249         return !colon || (slash && slash < colon) ||
 250                 has_dos_drive_prefix(url);
 251 }
 252
 253 static const char *prot_name(enum protocol protocol)
 254 {
 255         switch (protocol) {
 256                 case PROTO_LOCAL:
 257                 case PROTO_FILE:
 258                         return "file";
 259                 case PROTO_SSH:
 260                         return "ssh";
 261                 case PROTO_GIT:
 262                         return "git";
 263                 default:
 264                         return "unkown protocol";
 265         }
 266 }
 267
 268 static enum protocol get_protocol(const char *name)
 269 {
 270         if (!strcmp(name, "ssh"))
 271                 return PROTO_SSH;
 272         if (!strcmp(name, "git"))
 273                 return PROTO_GIT;
 274         if (!strcmp(name, "git+ssh"))
 275                 return PROTO_SSH;
 276         if (!strcmp(name, "ssh+git"))
 277                 return PROTO_SSH;
 278         if (!strcmp(name, "file"))
 279                 return PROTO_FILE;
 280         die("I don't handle protocol '%s'", name);
 281 }
 282
 283 #define STR_(s) # s
 284 #define STR(s)  STR_(s)
 285
 286 static void get_host_and_port(char **host, const char **port)
 287 {
 288         char *colon, *end;
 289
 290         if (*host[0] == '[') {
 291                 end = strchr(*host + 1, ']');
 292                 if (end) {
 293                         *end = 0;
 294                         end++;
 295                         (*host)++;
 296                 } else
 297                         end = *host;
 298         } else
 299                 end = *host;
 300         colon = strchr(end, ':');
 301
 302         if (colon) {
 303                 *colon = 0;
 304                 *port = colon + 1;
 305         }
 306 }
 307
 308 static void enable_keepalive(int sockfd)
 309 {
 310         int ka = 1;
 311
 312         if (setsockopt(sockfd, SOL_SOCKET, SO_KEEPALIVE, &ka, sizeof(ka)) < 0)
 313                 fprintf(stderr, "unable to set SO_KEEPALIVE on socket: %s\n",
 314                         strerror(errno));
 315 }
 316
 317 #ifndef NO_IPV6
 318
 319 static const char *ai_name(const struct addrinfo *ai)
 320 {
 321         static char addr[NI_MAXHOST];
 322         if (getnameinfo(ai->ai_addr, ai->ai_addrlen, addr, sizeof(addr), NULL, 0,
 323                         NI_NUMERICHOST) != 0)
 324                 strcpy(addr, "(unknown)");
 325
 326         return addr;
 327 }
 328
 329 /*
 330  * Returns a connected socket() fd, or else die()s.
 331  */
 332 static int git_tcp_connect_sock(char *host, int flags)
 333 {
 334         struct strbuf error_message = STRBUF_INIT;
 335         int sockfd = -1;
 336         const char *port = STR(DEFAULT_GIT_PORT);
 337         struct addrinfo hints, *ai0, *ai;
 338         int gai;
 339         int cnt = 0;
 340
 341         get_host_and_port(&host, &port);
 342         if (!*port)
 343                 port = "<none>";
 344
 345         memset(&hints, 0, sizeof(hints));
 346         hints.ai_socktype = SOCK_STREAM;
 347         hints.ai_protocol = IPPROTO_TCP;
 348
 349         if (flags & CONNECT_VERBOSE)
 350                 fprintf(stderr, "Looking up %s ... ", host);
 351
 352         gai = getaddrinfo(host, port, &hints, &ai);
 353         if (gai)
 354                 die("Unable to look up %s (port %s) (%s)", host, port, gai_strerror(gai));
 355
 356         if (flags & CONNECT_VERBOSE)
 357                 fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
 358
 359         for (ai0 = ai; ai; ai = ai->ai_next, cnt++) {
 360                 sockfd = socket(ai->ai_family,
 361                                 ai->ai_socktype, ai->ai_protocol);
 362                 if ((sockfd < 0) ||
 363                     (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0)) {
 364                         strbuf_addf(&error_message, "%s[%d: %s]: errno=%s\n",
 365                                     host, cnt, ai_name(ai), strerror(errno));
 366                         if (0 <= sockfd)
 367                                 close(sockfd);
 368                         sockfd = -1;
 369                         continue;
 370                 }
 371                 if (flags & CONNECT_VERBOSE)
 372                         fprintf(stderr, "%s ", ai_name(ai));
 373                 break;
 374         }
 375
 376         freeaddrinfo(ai0);
 377
 378         if (sockfd < 0)
 379                 die("unable to connect to %s:\n%s", host, error_message.buf);
 380
 381         enable_keepalive(sockfd);
 382
 383         if (flags & CONNECT_VERBOSE)
 384                 fprintf(stderr, "done.\n");
 385
 386         strbuf_release(&error_message);
 387
 388         return sockfd;
 389 }
 390
 391 #else /* NO_IPV6 */
 392
 393 /*
 394  * Returns a connected socket() fd, or else die()s.
 395  */
 396 static int git_tcp_connect_sock(char *host, int flags)
 397 {
 398         struct strbuf error_message = STRBUF_INIT;
 399         int sockfd = -1;
 400         const char *port = STR(DEFAULT_GIT_PORT);
 401         char *ep;
 402         struct hostent *he;
 403         struct sockaddr_in sa;
 404         char **ap;
 405         unsigned int nport;
 406         int cnt;
 407
 408         get_host_and_port(&host, &port);
 409
 410         if (flags & CONNECT_VERBOSE)
 411                 fprintf(stderr, "Looking up %s ... ", host);
 412
 413         he = gethostbyname(host);
 414         if (!he)
 415                 die("Unable to look up %s (%s)", host, hstrerror(h_errno));
 416         nport = strtoul(port, &ep, 10);
 417         if ( ep == port || *ep ) {
 418                 /* Not numeric */
 419                 struct servent *se = getservbyname(port,"tcp");
 420                 if ( !se )
 421                         die("Unknown port %s", port);
 422                 nport = se->s_port;
 423         }
 424
 425         if (flags & CONNECT_VERBOSE)
 426                 fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
 427
 428         for (cnt = 0, ap = he->h_addr_list; *ap; ap++, cnt++) {
 429                 memset(&sa, 0, sizeof sa);
 430                 sa.sin_family = he->h_addrtype;
 431                 sa.sin_port = htons(nport);
 432                 memcpy(&sa.sin_addr, *ap, he->h_length);
 433
 434                 sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
 435                 if ((sockfd < 0) ||
 436                     connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
 437                         strbuf_addf(&error_message, "%s[%d: %s]: errno=%s\n",
 438                                 host,
 439                                 cnt,
 440                                 inet_ntoa(*(struct in_addr *)&sa.sin_addr),
 441                                 strerror(errno));
 442                         if (0 <= sockfd)
 443                                 close(sockfd);
 444                         sockfd = -1;
 445                         continue;
 446                 }
 447                 if (flags & CONNECT_VERBOSE)
 448                         fprintf(stderr, "%s ",
 449                                 inet_ntoa(*(struct in_addr *)&sa.sin_addr));
 450                 break;
 451         }
 452
 453         if (sockfd < 0)
 454                 die("unable to connect to %s:\n%s", host, error_message.buf);
 455
 456         enable_keepalive(sockfd);
 457
 458         if (flags & CONNECT_VERBOSE)
 459                 fprintf(stderr, "done.\n");
 460
 461         return sockfd;
 462 }
 463
 464 #endif /* NO_IPV6 */
 465
 466
 467 static void git_tcp_connect(int fd[2], char *host, int flags)
 468 {
 469         int sockfd = git_tcp_connect_sock(host, flags);
 470
 471         fd[0] = sockfd;
 472         fd[1] = dup(sockfd);
 473 }
 474
 475
 476 static char *git_proxy_command;
 477
 478 static int git_proxy_command_options(const char *var, const char *value,
 479                 void *cb)
 480 {
 481         if (!strcmp(var, "core.gitproxy")) {
 482                 const char *for_pos;
 483                 int matchlen = -1;
 484                 int hostlen;
 485                 const char *rhost_name = cb;
 486                 int rhost_len = strlen(rhost_name);
 487
 488                 if (git_proxy_command)
 489                         return 0;
 490                 if (!value)
 491                         return config_error_nonbool(var);
 492                 /* [core]
 493                  * ;# matches www.kernel.org as well
 494                  * gitproxy = netcatter-1 for kernel.org
 495                  * gitproxy = netcatter-2 for sample.xz
 496                  * gitproxy = netcatter-default
 497                  */
 498                 for_pos = strstr(value, " for ");
 499                 if (!for_pos)
 500                         /* matches everybody */
 501                         matchlen = strlen(value);
 502                 else {
 503                         hostlen = strlen(for_pos + 5);
 504                         if (rhost_len < hostlen)
 505                                 matchlen = -1;
 506                         else if (!strncmp(for_pos + 5,
 507                                           rhost_name + rhost_len - hostlen,
 508                                           hostlen) &&
 509                                  ((rhost_len == hostlen) ||
 510                                   rhost_name[rhost_len - hostlen -1] == '.'))
 511                                 matchlen = for_pos - value;
 512                         else
 513                                 matchlen = -1;
 514                 }
 515                 if (0 <= matchlen) {
 516                         /* core.gitproxy = none for kernel.org */
 517                         if (matchlen == 4 &&
 518                             !memcmp(value, "none", 4))
 519                                 matchlen = 0;
 520                         git_proxy_command = xmemdupz(value, matchlen);
 521                 }
 522                 return 0;
 523         }
 524
 525         return git_default_config(var, value, cb);
 526 }
 527
 528 static int git_use_proxy(const char *host)
 529 {
 530         git_proxy_command = getenv("GIT_PROXY_COMMAND");
 531         git_config(git_proxy_command_options, (void*)host);
 532         return (git_proxy_command && *git_proxy_command);
 533 }
 534
 535 static struct child_process *git_proxy_connect(int fd[2], char *host)
 536 {
 537         const char *port = STR(DEFAULT_GIT_PORT);
 538         struct child_process *proxy;
 539
 540         get_host_and_port(&host, &port);
 541
 542         proxy = xcalloc(1, sizeof(*proxy));
 543         argv_array_push(&proxy->args, git_proxy_command);
 544         argv_array_push(&proxy->args, host);
 545         argv_array_push(&proxy->args, port);
 546         proxy->in = -1;
 547         proxy->out = -1;
 548         if (start_command(proxy))
 549                 die("cannot start proxy %s", git_proxy_command);
 550         fd[0] = proxy->out; /* read from proxy stdout */
 551         fd[1] = proxy->in;  /* write to proxy stdin */
 552         return proxy;
 553 }
 554
 555 static const char *get_port_numeric(const char *p)
 556 {
 557         char *end;
 558         if (p) {
 559                 long port = strtol(p + 1, &end, 10);
 560                 if (end != p + 1 && *end == '\0' && 0 <= port && port < 65536) {
 561                         return p;
 562                 }
 563         }
 564
 565         return NULL;
 566 }
 567
 568 /*
 569  * Extract protocol and relevant parts from the specified connection URL.
 570  * The caller must free() the returned strings.
 571  */
 572 static enum protocol parse_connect_url(const char *url_orig, char **ret_host,
 573                                        char **ret_path)
 574 {
 575         char *url;
 576         char *host, *path;
 577         char *end;
 578         int separator = '/';
 579         enum protocol protocol = PROTO_LOCAL;
 580
 581         if (is_url(url_orig))
 582                 url = url_decode(url_orig);
 583         else
 584                 url = xstrdup(url_orig);
 585
 586         host = strstr(url, "://");
 587         if (host) {
 588                 *host = '\0';
 589                 protocol = get_protocol(url);
 590                 host += 3;
 591         } else {
 592                 host = url;
 593                 if (!url_is_local_not_ssh(url)) {
 594                         protocol = PROTO_SSH;
 595                         separator = ':';
 596                 }
 597         }
 598
 599         /*
 600          * Don't do destructive transforms as protocol code does
 601          * '[]' unwrapping in get_host_and_port()
 602          */
 603         if (host[0] == '[') {
 604                 end = strchr(host + 1, ']');
 605                 if (end) {
 606                         end++;
 607                 } else
 608                         end = host;
 609         } else
 610                 end = host;
 611
 612         if (protocol == PROTO_LOCAL)
 613                 path = end;
 614         else if (protocol == PROTO_FILE && has_dos_drive_prefix(end))
 615                 path = end; /* "file://$(pwd)" may be "file://C:/projects/repo" */
 616         else
 617                 path = strchr(end, separator);
 618
 619         if (!path || !*path)
 620                 die("No path specified. See 'man git-pull' for valid url syntax");
 621
 622         /*
 623          * null-terminate hostname and point path to ~ for URL's like this:
 624          *    ssh://host.xz/~user/repo
 625          */
 626
 627         end = path; /* Need to \0 terminate host here */
 628         if (separator == ':')
 629                 path++; /* path starts after ':' */
 630         if (protocol == PROTO_GIT || protocol == PROTO_SSH) {
 631                 if (path[1] == '~')
 632                         path++;
 633         }
 634
 635         path = xstrdup(path);
 636         *end = '\0';
 637
 638         *ret_host = xstrdup(host);
 639         *ret_path = path;
 640         free(url);
 641         return protocol;
 642 }
 643
 644 static struct child_process no_fork;
 645
 646 /*
 647  * This returns a dummy child_process if the transport protocol does not
 648  * need fork(2), or a struct child_process object if it does.  Once done,
 649  * finish the connection with finish_connect() with the value returned from
 650  * this function (it is safe to call finish_connect() with NULL to support
 651  * the former case).
 652  *
 653  * If it returns, the connect is successful; it just dies on errors (this
 654  * will hopefully be changed in a libification effort, to return NULL when
 655  * the connection failed).
 656  */
 657 struct child_process *git_connect(int fd[2], const char *url,
 658                                   const char *prog, int flags)
 659 {
 660         char *hostandport, *path;
 661         struct child_process *conn = &no_fork;
 662         enum protocol protocol;
 663         struct strbuf cmd = STRBUF_INIT;
 664
 665         /* Without this we cannot rely on waitpid() to tell
 666          * what happened to our children.
 667          */
 668         signal(SIGCHLD, SIG_DFL);
 669
 670         protocol = parse_connect_url(url, &hostandport, &path);
 671         if (flags & CONNECT_DIAG_URL) {
 672                 printf("Diag: url=%s\n", url ? url : "NULL");
 673                 printf("Diag: protocol=%s\n", prot_name(protocol));
 674                 printf("Diag: hostandport=%s\n", hostandport ? hostandport : "NULL");
 675                 printf("Diag: path=%s\n", path ? path : "NULL");
 676                 conn = NULL;
 677         } else if (protocol == PROTO_GIT) {
 678                 /* These underlying connection commands die() if they
 679                  * cannot connect.
 680                  */
 681                 char *target_host = xstrdup(hostandport);
 682                 if (git_use_proxy(hostandport))
 683                         conn = git_proxy_connect(fd, hostandport);
 684                 else
 685                         git_tcp_connect(fd, hostandport, flags);
 686                 /*
 687                  * Separate original protocol components prog and path
 688                  * from extended host header with a NUL byte.
 689                  *
 690                  * Note: Do not add any other headers here!  Doing so
 691                  * will cause older git-daemon servers to crash.
 692                  */
 693                 packet_write(fd[1],
 694                              "%s %s%chost=%s%c",
 695                              prog, path, 0,
 696                              target_host, 0);
 697                 free(target_host);
 698         } else {
 699                 conn = xcalloc(1, sizeof(*conn));
 700
 701                 strbuf_addstr(&cmd, prog);
 702                 strbuf_addch(&cmd, ' ');
 703                 sq_quote_buf(&cmd, path);
 704
 705                 conn->in = conn->out = -1;
 706                 if (protocol == PROTO_SSH) {
 707                         const char *ssh = getenv("GIT_SSH");
 708                         int putty = ssh && strcasestr(ssh, "plink");
 709                         char *ssh_host = hostandport;
 710                         const char *port = NULL;
 711                         get_host_and_port(&ssh_host, &port);
 712                         port = get_port_numeric(port);
 713
 714                         if (!ssh) ssh = "ssh";
 715
 716                         argv_array_push(&conn->args, ssh);
 717                         if (putty && !strcasestr(ssh, "tortoiseplink"))
 718                                 argv_array_push(&conn->args, "-batch");
 719                         if (port) {
 720                                 /* P is for PuTTY, p is for OpenSSH */
 721                                 argv_array_push(&conn->args, putty ? "-P" : "-p");
 722                                 argv_array_push(&conn->args, port);
 723                         }
 724                         argv_array_push(&conn->args, ssh_host);
 725                 } else {
 726                         /* remove repo-local variables from the environment */
 727                         conn->env = local_repo_env;
 728                         conn->use_shell = 1;
 729                 }
 730                 argv_array_push(&conn->args, cmd.buf);
 731
 732                 if (start_command(conn))
 733                         die("unable to fork");
 734
 735                 fd[0] = conn->out; /* read from child's stdout */
 736                 fd[1] = conn->in;  /* write to child's stdin */
 737                 strbuf_release(&cmd);
 738         }
 739         free(hostandport);
 740         free(path);
 741         return conn;
 742 }
 743
 744 int git_connection_is_socket(struct child_process *conn)
 745 {
 746         return conn == &no_fork;
 747 }
 748
 749 int finish_connect(struct child_process *conn)
 750 {
 751         int code;
 752         if (!conn || git_connection_is_socket(conn))
 753                 return 0;
 754
 755         code = finish_command(conn);
 756         free(conn);
 757         return code;
 758 }