Merge branch 'as/docfix-reflog-expire-unreachable'
[git] / 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, unsigned int flags)
17 {
18         if (!flags)
19                 return 1;
20
21         if (!skip_prefix(name, "refs/", &name))
22                 return 0;
23
24         /* REF_NORMAL means that we don't want the magic fake tag refs */
25         if ((flags & REF_NORMAL) && check_refname_format(name, 0))
26                 return 0;
27
28         /* REF_HEADS means that we want regular branch heads */
29         if ((flags & REF_HEADS) && starts_with(name, "heads/"))
30                 return 1;
31
32         /* REF_TAGS means that we want tags */
33         if ((flags & REF_TAGS) && starts_with(name, "tags/"))
34                 return 1;
35
36         /* All type bits clear means that we are ok with anything */
37         return !(flags & ~REF_NORMAL);
38 }
39
40 int check_ref_type(const struct ref *ref, int flags)
41 {
42         return check_ref(ref->name, flags);
43 }
44
45 static void die_initial_contact(int got_at_least_one_head)
46 {
47         if (got_at_least_one_head)
48                 die("The remote end hung up upon initial contact");
49         else
50                 die("Could not read from remote repository.\n\n"
51                     "Please make sure you have the correct access rights\n"
52                     "and the repository exists.");
53 }
54
55 static void parse_one_symref_info(struct string_list *symref, const char *val, int len)
56 {
57         char *sym, *target;
58         struct string_list_item *item;
59
60         if (!len)
61                 return; /* just "symref" */
62         /* e.g. "symref=HEAD:refs/heads/master" */
63         sym = xmemdupz(val, len);
64         target = strchr(sym, ':');
65         if (!target)
66                 /* just "symref=something" */
67                 goto reject;
68         *(target++) = '\0';
69         if (check_refname_format(sym, REFNAME_ALLOW_ONELEVEL) ||
70             check_refname_format(target, REFNAME_ALLOW_ONELEVEL))
71                 /* "symref=bogus:pair */
72                 goto reject;
73         item = string_list_append(symref, sym);
74         item->util = target;
75         return;
76 reject:
77         free(sym);
78         return;
79 }
80
81 static void annotate_refs_with_symref_info(struct ref *ref)
82 {
83         struct string_list symref = STRING_LIST_INIT_DUP;
84         const char *feature_list = server_capabilities;
85
86         while (feature_list) {
87                 int len;
88                 const char *val;
89
90                 val = parse_feature_value(feature_list, "symref", &len);
91                 if (!val)
92                         break;
93                 parse_one_symref_info(&symref, val, len);
94                 feature_list = val + 1;
95         }
96         string_list_sort(&symref);
97
98         for (; ref; ref = ref->next) {
99                 struct string_list_item *item;
100                 item = string_list_lookup(&symref, ref->name);
101                 if (!item)
102                         continue;
103                 ref->symref = xstrdup((char *)item->util);
104         }
105         string_list_clear(&symref, 0);
106 }
107
108 /*
109  * Read all the refs from the other end
110  */
111 struct ref **get_remote_heads(int in, char *src_buf, size_t src_len,
112                               struct ref **list, unsigned int flags,
113                               struct sha1_array *extra_have,
114                               struct sha1_array *shallow_points)
115 {
116         struct ref **orig_list = list;
117         int got_at_least_one_head = 0;
118
119         *list = NULL;
120         for (;;) {
121                 struct ref *ref;
122                 unsigned char old_sha1[20];
123                 char *name;
124                 int len, name_len;
125                 char *buffer = packet_buffer;
126                 const char *arg;
127
128                 len = packet_read(in, &src_buf, &src_len,
129                                   packet_buffer, sizeof(packet_buffer),
130                                   PACKET_READ_GENTLE_ON_EOF |
131                                   PACKET_READ_CHOMP_NEWLINE);
132                 if (len < 0)
133                         die_initial_contact(got_at_least_one_head);
134
135                 if (!len)
136                         break;
137
138                 if (len > 4 && skip_prefix(buffer, "ERR ", &arg))
139                         die("remote error: %s", arg);
140
141                 if (len == 48 && skip_prefix(buffer, "shallow ", &arg)) {
142                         if (get_sha1_hex(arg, old_sha1))
143                                 die("protocol error: expected shallow sha-1, got '%s'", arg);
144                         if (!shallow_points)
145                                 die("repository on the other end cannot be shallow");
146                         sha1_array_append(shallow_points, old_sha1);
147                         continue;
148                 }
149
150                 if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
151                         die("protocol error: expected sha/ref, got '%s'", buffer);
152                 name = buffer + 41;
153
154                 name_len = strlen(name);
155                 if (len != name_len + 41) {
156                         free(server_capabilities);
157                         server_capabilities = xstrdup(name + name_len + 1);
158                 }
159
160                 if (extra_have && !strcmp(name, ".have")) {
161                         sha1_array_append(extra_have, old_sha1);
162                         continue;
163                 }
164
165                 if (!check_ref(name, flags))
166                         continue;
167                 ref = alloc_ref(buffer + 41);
168                 hashcpy(ref->old_sha1, old_sha1);
169                 *list = ref;
170                 list = &ref->next;
171                 got_at_least_one_head = 1;
172         }
173
174         annotate_refs_with_symref_info(*orig_list);
175
176         return list;
177 }
178
179 static const char *parse_feature_value(const char *feature_list, const char *feature, int *lenp)
180 {
181         int len;
182
183         if (!feature_list)
184                 return NULL;
185
186         len = strlen(feature);
187         while (*feature_list) {
188                 const char *found = strstr(feature_list, feature);
189                 if (!found)
190                         return NULL;
191                 if (feature_list == found || isspace(found[-1])) {
192                         const char *value = found + len;
193                         /* feature with no value (e.g., "thin-pack") */
194                         if (!*value || isspace(*value)) {
195                                 if (lenp)
196                                         *lenp = 0;
197                                 return value;
198                         }
199                         /* feature with a value (e.g., "agent=git/1.2.3") */
200                         else if (*value == '=') {
201                                 value++;
202                                 if (lenp)
203                                         *lenp = strcspn(value, " \t\n");
204                                 return value;
205                         }
206                         /*
207                          * otherwise we matched a substring of another feature;
208                          * keep looking
209                          */
210                 }
211                 feature_list = found + 1;
212         }
213         return NULL;
214 }
215
216 int parse_feature_request(const char *feature_list, const char *feature)
217 {
218         return !!parse_feature_value(feature_list, feature, NULL);
219 }
220
221 const char *server_feature_value(const char *feature, int *len)
222 {
223         return parse_feature_value(server_capabilities, feature, len);
224 }
225
226 int server_supports(const char *feature)
227 {
228         return !!server_feature_value(feature, NULL);
229 }
230
231 enum protocol {
232         PROTO_LOCAL = 1,
233         PROTO_FILE,
234         PROTO_SSH,
235         PROTO_GIT
236 };
237
238 int url_is_local_not_ssh(const char *url)
239 {
240         const char *colon = strchr(url, ':');
241         const char *slash = strchr(url, '/');
242         return !colon || (slash && slash < colon) ||
243                 has_dos_drive_prefix(url);
244 }
245
246 static const char *prot_name(enum protocol protocol)
247 {
248         switch (protocol) {
249                 case PROTO_LOCAL:
250                 case PROTO_FILE:
251                         return "file";
252                 case PROTO_SSH:
253                         return "ssh";
254                 case PROTO_GIT:
255                         return "git";
256                 default:
257                         return "unkown protocol";
258         }
259 }
260
261 static enum protocol get_protocol(const char *name)
262 {
263         if (!strcmp(name, "ssh"))
264                 return PROTO_SSH;
265         if (!strcmp(name, "git"))
266                 return PROTO_GIT;
267         if (!strcmp(name, "git+ssh"))
268                 return PROTO_SSH;
269         if (!strcmp(name, "ssh+git"))
270                 return PROTO_SSH;
271         if (!strcmp(name, "file"))
272                 return PROTO_FILE;
273         die("I don't handle protocol '%s'", name);
274 }
275
276 static char *host_end(char **hoststart, int removebrackets)
277 {
278         char *host = *hoststart;
279         char *end;
280         char *start = strstr(host, "@[");
281         if (start)
282                 start++; /* Jump over '@' */
283         else
284                 start = host;
285         if (start[0] == '[') {
286                 end = strchr(start + 1, ']');
287                 if (end) {
288                         if (removebrackets) {
289                                 *end = 0;
290                                 memmove(start, start + 1, end - start);
291                                 end++;
292                         }
293                 } else
294                         end = host;
295         } else
296                 end = host;
297         return end;
298 }
299
300 #define STR_(s) # s
301 #define STR(s)  STR_(s)
302
303 static void get_host_and_port(char **host, const char **port)
304 {
305         char *colon, *end;
306         end = host_end(host, 1);
307         colon = strchr(end, ':');
308         if (colon) {
309                 long portnr = strtol(colon + 1, &end, 10);
310                 if (end != colon + 1 && *end == '\0' && 0 <= portnr && portnr < 65536) {
311                         *colon = 0;
312                         *port = colon + 1;
313                 } else if (!colon[1]) {
314                         *colon = 0;
315                 }
316         }
317 }
318
319 static void enable_keepalive(int sockfd)
320 {
321         int ka = 1;
322
323         if (setsockopt(sockfd, SOL_SOCKET, SO_KEEPALIVE, &ka, sizeof(ka)) < 0)
324                 fprintf(stderr, "unable to set SO_KEEPALIVE on socket: %s\n",
325                         strerror(errno));
326 }
327
328 #ifndef NO_IPV6
329
330 static const char *ai_name(const struct addrinfo *ai)
331 {
332         static char addr[NI_MAXHOST];
333         if (getnameinfo(ai->ai_addr, ai->ai_addrlen, addr, sizeof(addr), NULL, 0,
334                         NI_NUMERICHOST) != 0)
335                 strcpy(addr, "(unknown)");
336
337         return addr;
338 }
339
340 /*
341  * Returns a connected socket() fd, or else die()s.
342  */
343 static int git_tcp_connect_sock(char *host, int flags)
344 {
345         struct strbuf error_message = STRBUF_INIT;
346         int sockfd = -1;
347         const char *port = STR(DEFAULT_GIT_PORT);
348         struct addrinfo hints, *ai0, *ai;
349         int gai;
350         int cnt = 0;
351
352         get_host_and_port(&host, &port);
353         if (!*port)
354                 port = "<none>";
355
356         memset(&hints, 0, sizeof(hints));
357         hints.ai_socktype = SOCK_STREAM;
358         hints.ai_protocol = IPPROTO_TCP;
359
360         if (flags & CONNECT_VERBOSE)
361                 fprintf(stderr, "Looking up %s ... ", host);
362
363         gai = getaddrinfo(host, port, &hints, &ai);
364         if (gai)
365                 die("Unable to look up %s (port %s) (%s)", host, port, gai_strerror(gai));
366
367         if (flags & CONNECT_VERBOSE)
368                 fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
369
370         for (ai0 = ai; ai; ai = ai->ai_next, cnt++) {
371                 sockfd = socket(ai->ai_family,
372                                 ai->ai_socktype, ai->ai_protocol);
373                 if ((sockfd < 0) ||
374                     (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0)) {
375                         strbuf_addf(&error_message, "%s[%d: %s]: errno=%s\n",
376                                     host, cnt, ai_name(ai), strerror(errno));
377                         if (0 <= sockfd)
378                                 close(sockfd);
379                         sockfd = -1;
380                         continue;
381                 }
382                 if (flags & CONNECT_VERBOSE)
383                         fprintf(stderr, "%s ", ai_name(ai));
384                 break;
385         }
386
387         freeaddrinfo(ai0);
388
389         if (sockfd < 0)
390                 die("unable to connect to %s:\n%s", host, error_message.buf);
391
392         enable_keepalive(sockfd);
393
394         if (flags & CONNECT_VERBOSE)
395                 fprintf(stderr, "done.\n");
396
397         strbuf_release(&error_message);
398
399         return sockfd;
400 }
401
402 #else /* NO_IPV6 */
403
404 /*
405  * Returns a connected socket() fd, or else die()s.
406  */
407 static int git_tcp_connect_sock(char *host, int flags)
408 {
409         struct strbuf error_message = STRBUF_INIT;
410         int sockfd = -1;
411         const char *port = STR(DEFAULT_GIT_PORT);
412         char *ep;
413         struct hostent *he;
414         struct sockaddr_in sa;
415         char **ap;
416         unsigned int nport;
417         int cnt;
418
419         get_host_and_port(&host, &port);
420
421         if (flags & CONNECT_VERBOSE)
422                 fprintf(stderr, "Looking up %s ... ", host);
423
424         he = gethostbyname(host);
425         if (!he)
426                 die("Unable to look up %s (%s)", host, hstrerror(h_errno));
427         nport = strtoul(port, &ep, 10);
428         if ( ep == port || *ep ) {
429                 /* Not numeric */
430                 struct servent *se = getservbyname(port,"tcp");
431                 if ( !se )
432                         die("Unknown port %s", port);
433                 nport = se->s_port;
434         }
435
436         if (flags & CONNECT_VERBOSE)
437                 fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
438
439         for (cnt = 0, ap = he->h_addr_list; *ap; ap++, cnt++) {
440                 memset(&sa, 0, sizeof sa);
441                 sa.sin_family = he->h_addrtype;
442                 sa.sin_port = htons(nport);
443                 memcpy(&sa.sin_addr, *ap, he->h_length);
444
445                 sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
446                 if ((sockfd < 0) ||
447                     connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
448                         strbuf_addf(&error_message, "%s[%d: %s]: errno=%s\n",
449                                 host,
450                                 cnt,
451                                 inet_ntoa(*(struct in_addr *)&sa.sin_addr),
452                                 strerror(errno));
453                         if (0 <= sockfd)
454                                 close(sockfd);
455                         sockfd = -1;
456                         continue;
457                 }
458                 if (flags & CONNECT_VERBOSE)
459                         fprintf(stderr, "%s ",
460                                 inet_ntoa(*(struct in_addr *)&sa.sin_addr));
461                 break;
462         }
463
464         if (sockfd < 0)
465                 die("unable to connect to %s:\n%s", host, error_message.buf);
466
467         enable_keepalive(sockfd);
468
469         if (flags & CONNECT_VERBOSE)
470                 fprintf(stderr, "done.\n");
471
472         return sockfd;
473 }
474
475 #endif /* NO_IPV6 */
476
477
478 static void git_tcp_connect(int fd[2], char *host, int flags)
479 {
480         int sockfd = git_tcp_connect_sock(host, flags);
481
482         fd[0] = sockfd;
483         fd[1] = dup(sockfd);
484 }
485
486
487 static char *git_proxy_command;
488
489 static int git_proxy_command_options(const char *var, const char *value,
490                 void *cb)
491 {
492         if (!strcmp(var, "core.gitproxy")) {
493                 const char *for_pos;
494                 int matchlen = -1;
495                 int hostlen;
496                 const char *rhost_name = cb;
497                 int rhost_len = strlen(rhost_name);
498
499                 if (git_proxy_command)
500                         return 0;
501                 if (!value)
502                         return config_error_nonbool(var);
503                 /* [core]
504                  * ;# matches www.kernel.org as well
505                  * gitproxy = netcatter-1 for kernel.org
506                  * gitproxy = netcatter-2 for sample.xz
507                  * gitproxy = netcatter-default
508                  */
509                 for_pos = strstr(value, " for ");
510                 if (!for_pos)
511                         /* matches everybody */
512                         matchlen = strlen(value);
513                 else {
514                         hostlen = strlen(for_pos + 5);
515                         if (rhost_len < hostlen)
516                                 matchlen = -1;
517                         else if (!strncmp(for_pos + 5,
518                                           rhost_name + rhost_len - hostlen,
519                                           hostlen) &&
520                                  ((rhost_len == hostlen) ||
521                                   rhost_name[rhost_len - hostlen -1] == '.'))
522                                 matchlen = for_pos - value;
523                         else
524                                 matchlen = -1;
525                 }
526                 if (0 <= matchlen) {
527                         /* core.gitproxy = none for kernel.org */
528                         if (matchlen == 4 &&
529                             !memcmp(value, "none", 4))
530                                 matchlen = 0;
531                         git_proxy_command = xmemdupz(value, matchlen);
532                 }
533                 return 0;
534         }
535
536         return git_default_config(var, value, cb);
537 }
538
539 static int git_use_proxy(const char *host)
540 {
541         git_proxy_command = getenv("GIT_PROXY_COMMAND");
542         git_config(git_proxy_command_options, (void*)host);
543         return (git_proxy_command && *git_proxy_command);
544 }
545
546 static struct child_process *git_proxy_connect(int fd[2], char *host)
547 {
548         const char *port = STR(DEFAULT_GIT_PORT);
549         struct child_process *proxy;
550
551         get_host_and_port(&host, &port);
552
553         proxy = xmalloc(sizeof(*proxy));
554         child_process_init(proxy);
555         argv_array_push(&proxy->args, git_proxy_command);
556         argv_array_push(&proxy->args, host);
557         argv_array_push(&proxy->args, port);
558         proxy->in = -1;
559         proxy->out = -1;
560         if (start_command(proxy))
561                 die("cannot start proxy %s", git_proxy_command);
562         fd[0] = proxy->out; /* read from proxy stdout */
563         fd[1] = proxy->in;  /* write to proxy stdin */
564         return proxy;
565 }
566
567 static char *get_port(char *host)
568 {
569         char *end;
570         char *p = strchr(host, ':');
571
572         if (p) {
573                 long port = strtol(p + 1, &end, 10);
574                 if (end != p + 1 && *end == '\0' && 0 <= port && port < 65536) {
575                         *p = '\0';
576                         return p+1;
577                 }
578         }
579
580         return NULL;
581 }
582
583 /*
584  * Extract protocol and relevant parts from the specified connection URL.
585  * The caller must free() the returned strings.
586  */
587 static enum protocol parse_connect_url(const char *url_orig, char **ret_host,
588                                        char **ret_path)
589 {
590         char *url;
591         char *host, *path;
592         char *end;
593         int separator = '/';
594         enum protocol protocol = PROTO_LOCAL;
595
596         if (is_url(url_orig))
597                 url = url_decode(url_orig);
598         else
599                 url = xstrdup(url_orig);
600
601         host = strstr(url, "://");
602         if (host) {
603                 *host = '\0';
604                 protocol = get_protocol(url);
605                 host += 3;
606         } else {
607                 host = url;
608                 if (!url_is_local_not_ssh(url)) {
609                         protocol = PROTO_SSH;
610                         separator = ':';
611                 }
612         }
613
614         /*
615          * Don't do destructive transforms as protocol code does
616          * '[]' unwrapping in get_host_and_port()
617          */
618         end = host_end(&host, 0);
619
620         if (protocol == PROTO_LOCAL)
621                 path = end;
622         else if (protocol == PROTO_FILE && has_dos_drive_prefix(end))
623                 path = end; /* "file://$(pwd)" may be "file://C:/projects/repo" */
624         else
625                 path = strchr(end, separator);
626
627         if (!path || !*path)
628                 die("No path specified. See 'man git-pull' for valid url syntax");
629
630         /*
631          * null-terminate hostname and point path to ~ for URL's like this:
632          *    ssh://host.xz/~user/repo
633          */
634
635         end = path; /* Need to \0 terminate host here */
636         if (separator == ':')
637                 path++; /* path starts after ':' */
638         if (protocol == PROTO_GIT || protocol == PROTO_SSH) {
639                 if (path[1] == '~')
640                         path++;
641         }
642
643         path = xstrdup(path);
644         *end = '\0';
645
646         *ret_host = xstrdup(host);
647         *ret_path = path;
648         free(url);
649         return protocol;
650 }
651
652 static struct child_process no_fork = CHILD_PROCESS_INIT;
653
654 /*
655  * This returns a dummy child_process if the transport protocol does not
656  * need fork(2), or a struct child_process object if it does.  Once done,
657  * finish the connection with finish_connect() with the value returned from
658  * this function (it is safe to call finish_connect() with NULL to support
659  * the former case).
660  *
661  * If it returns, the connect is successful; it just dies on errors (this
662  * will hopefully be changed in a libification effort, to return NULL when
663  * the connection failed).
664  */
665 struct child_process *git_connect(int fd[2], const char *url,
666                                   const char *prog, int flags)
667 {
668         char *hostandport, *path;
669         struct child_process *conn = &no_fork;
670         enum protocol protocol;
671         struct strbuf cmd = STRBUF_INIT;
672
673         /* Without this we cannot rely on waitpid() to tell
674          * what happened to our children.
675          */
676         signal(SIGCHLD, SIG_DFL);
677
678         protocol = parse_connect_url(url, &hostandport, &path);
679         if ((flags & CONNECT_DIAG_URL) && (protocol != PROTO_SSH)) {
680                 printf("Diag: url=%s\n", url ? url : "NULL");
681                 printf("Diag: protocol=%s\n", prot_name(protocol));
682                 printf("Diag: hostandport=%s\n", hostandport ? hostandport : "NULL");
683                 printf("Diag: path=%s\n", path ? path : "NULL");
684                 conn = NULL;
685         } else if (protocol == PROTO_GIT) {
686                 /*
687                  * Set up virtual host information based on where we will
688                  * connect, unless the user has overridden us in
689                  * the environment.
690                  */
691                 char *target_host = getenv("GIT_OVERRIDE_VIRTUAL_HOST");
692                 if (target_host)
693                         target_host = xstrdup(target_host);
694                 else
695                         target_host = xstrdup(hostandport);
696
697                 /* These underlying connection commands die() if they
698                  * cannot connect.
699                  */
700                 if (git_use_proxy(hostandport))
701                         conn = git_proxy_connect(fd, hostandport);
702                 else
703                         git_tcp_connect(fd, hostandport, flags);
704                 /*
705                  * Separate original protocol components prog and path
706                  * from extended host header with a NUL byte.
707                  *
708                  * Note: Do not add any other headers here!  Doing so
709                  * will cause older git-daemon servers to crash.
710                  */
711                 packet_write(fd[1],
712                              "%s %s%chost=%s%c",
713                              prog, path, 0,
714                              target_host, 0);
715                 free(target_host);
716         } else {
717                 conn = xmalloc(sizeof(*conn));
718                 child_process_init(conn);
719
720                 strbuf_addstr(&cmd, prog);
721                 strbuf_addch(&cmd, ' ');
722                 sq_quote_buf(&cmd, path);
723
724                 conn->in = conn->out = -1;
725                 if (protocol == PROTO_SSH) {
726                         const char *ssh;
727                         int putty, tortoiseplink = 0;
728                         char *ssh_host = hostandport;
729                         const char *port = NULL;
730                         get_host_and_port(&ssh_host, &port);
731
732                         if (!port)
733                                 port = get_port(ssh_host);
734
735                         if (flags & CONNECT_DIAG_URL) {
736                                 printf("Diag: url=%s\n", url ? url : "NULL");
737                                 printf("Diag: protocol=%s\n", prot_name(protocol));
738                                 printf("Diag: userandhost=%s\n", ssh_host ? ssh_host : "NULL");
739                                 printf("Diag: port=%s\n", port ? port : "NONE");
740                                 printf("Diag: path=%s\n", path ? path : "NULL");
741
742                                 free(hostandport);
743                                 free(path);
744                                 free(conn);
745                                 return NULL;
746                         }
747
748                         ssh = getenv("GIT_SSH_COMMAND");
749                         if (ssh) {
750                                 conn->use_shell = 1;
751                                 putty = 0;
752                         } else {
753                                 const char *base;
754                                 char *ssh_dup;
755
756                                 ssh = getenv("GIT_SSH");
757                                 if (!ssh)
758                                         ssh = "ssh";
759
760                                 ssh_dup = xstrdup(ssh);
761                                 base = basename(ssh_dup);
762
763                                 tortoiseplink = !strcasecmp(base, "tortoiseplink") ||
764                                         !strcasecmp(base, "tortoiseplink.exe");
765                                 putty = !strcasecmp(base, "plink") ||
766                                         !strcasecmp(base, "plink.exe") || tortoiseplink;
767
768                                 free(ssh_dup);
769                         }
770
771                         argv_array_push(&conn->args, ssh);
772                         if (tortoiseplink)
773                                 argv_array_push(&conn->args, "-batch");
774                         if (port) {
775                                 /* P is for PuTTY, p is for OpenSSH */
776                                 argv_array_push(&conn->args, putty ? "-P" : "-p");
777                                 argv_array_push(&conn->args, port);
778                         }
779                         argv_array_push(&conn->args, ssh_host);
780                 } else {
781                         /* remove repo-local variables from the environment */
782                         conn->env = local_repo_env;
783                         conn->use_shell = 1;
784                 }
785                 argv_array_push(&conn->args, cmd.buf);
786
787                 if (start_command(conn))
788                         die("unable to fork");
789
790                 fd[0] = conn->out; /* read from child's stdout */
791                 fd[1] = conn->in;  /* write to child's stdin */
792                 strbuf_release(&cmd);
793         }
794         free(hostandport);
795         free(path);
796         return conn;
797 }
798
799 int git_connection_is_socket(struct child_process *conn)
800 {
801         return conn == &no_fork;
802 }
803
804 int finish_connect(struct child_process *conn)
805 {
806         int code;
807         if (!conn || git_connection_is_socket(conn))
808                 return 0;
809
810         code = finish_command(conn);
811         free(conn);
812         return code;
813 }