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