Documentation/describe: improve one-line summary
[git.git] / connect.c
blobd47d0ec6040fdb8b07a689e299dac121bb468717
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"
13 static char *server_capabilities;
14 static const char *parse_feature_value(const char *, const char *, int *);
16 static int check_ref(const char *name, unsigned int flags)
18 if (!flags)
19 return 1;
21 if (!skip_prefix(name, "refs/", &name))
22 return 0;
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;
28 /* REF_HEADS means that we want regular branch heads */
29 if ((flags & REF_HEADS) && starts_with(name, "heads/"))
30 return 1;
32 /* REF_TAGS means that we want tags */
33 if ((flags & REF_TAGS) && starts_with(name, "tags/"))
34 return 1;
36 /* All type bits clear means that we are ok with anything */
37 return !(flags & ~REF_NORMAL);
40 int check_ref_type(const struct ref *ref, int flags)
42 return check_ref(ref->name, flags);
45 static void die_initial_contact(int got_at_least_one_head)
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.");
55 static void parse_one_symref_info(struct string_list *symref, const char *val, int len)
57 char *sym, *target;
58 struct string_list_item *item;
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;
81 static void annotate_refs_with_symref_info(struct ref *ref)
83 struct string_list symref = STRING_LIST_INIT_DUP;
84 const char *feature_list = server_capabilities;
86 while (feature_list) {
87 int len;
88 const char *val;
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;
96 sort_string_list(&symref);
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);
105 string_list_clear(&symref, 0);
109 * Read all the refs from the other end
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)
116 struct ref **orig_list = list;
117 int got_at_least_one_head = 0;
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;
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);
135 if (!len)
136 break;
138 if (len > 4 && skip_prefix(buffer, "ERR ", &arg))
139 die("remote error: %s", arg);
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;
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;
154 name_len = strlen(name);
155 if (len != name_len + 41) {
156 free(server_capabilities);
157 server_capabilities = xstrdup(name + name_len + 1);
160 if (extra_have &&
161 name_len == 5 && !memcmp(".have", name, 5)) {
162 sha1_array_append(extra_have, old_sha1);
163 continue;
166 if (!check_ref(name, flags))
167 continue;
168 ref = alloc_ref(buffer + 41);
169 hashcpy(ref->old_sha1, old_sha1);
170 *list = ref;
171 list = &ref->next;
172 got_at_least_one_head = 1;
175 annotate_refs_with_symref_info(*orig_list);
177 return list;
180 static const char *parse_feature_value(const char *feature_list, const char *feature, int *lenp)
182 int len;
184 if (!feature_list)
185 return NULL;
187 len = strlen(feature);
188 while (*feature_list) {
189 const char *found = strstr(feature_list, feature);
190 if (!found)
191 return NULL;
192 if (feature_list == found || isspace(found[-1])) {
193 const char *value = found + len;
194 /* feature with no value (e.g., "thin-pack") */
195 if (!*value || isspace(*value)) {
196 if (lenp)
197 *lenp = 0;
198 return value;
200 /* feature with a value (e.g., "agent=git/1.2.3") */
201 else if (*value == '=') {
202 value++;
203 if (lenp)
204 *lenp = strcspn(value, " \t\n");
205 return value;
208 * otherwise we matched a substring of another feature;
209 * keep looking
212 feature_list = found + 1;
214 return NULL;
217 int parse_feature_request(const char *feature_list, const char *feature)
219 return !!parse_feature_value(feature_list, feature, NULL);
222 const char *server_feature_value(const char *feature, int *len)
224 return parse_feature_value(server_capabilities, feature, len);
227 int server_supports(const char *feature)
229 return !!server_feature_value(feature, NULL);
232 enum protocol {
233 PROTO_LOCAL = 1,
234 PROTO_FILE,
235 PROTO_SSH,
236 PROTO_GIT
239 int url_is_local_not_ssh(const char *url)
241 const char *colon = strchr(url, ':');
242 const char *slash = strchr(url, '/');
243 return !colon || (slash && slash < colon) ||
244 has_dos_drive_prefix(url);
247 static const char *prot_name(enum protocol protocol)
249 switch (protocol) {
250 case PROTO_LOCAL:
251 case PROTO_FILE:
252 return "file";
253 case PROTO_SSH:
254 return "ssh";
255 case PROTO_GIT:
256 return "git";
257 default:
258 return "unkown protocol";
262 static enum protocol get_protocol(const char *name)
264 if (!strcmp(name, "ssh"))
265 return PROTO_SSH;
266 if (!strcmp(name, "git"))
267 return PROTO_GIT;
268 if (!strcmp(name, "git+ssh"))
269 return PROTO_SSH;
270 if (!strcmp(name, "ssh+git"))
271 return PROTO_SSH;
272 if (!strcmp(name, "file"))
273 return PROTO_FILE;
274 die("I don't handle protocol '%s'", name);
277 #define STR_(s) # s
278 #define STR(s) STR_(s)
280 static void get_host_and_port(char **host, const char **port)
282 char *colon, *end;
284 if (*host[0] == '[') {
285 end = strchr(*host + 1, ']');
286 if (end) {
287 *end = 0;
288 end++;
289 (*host)++;
290 } else
291 end = *host;
292 } else
293 end = *host;
294 colon = strchr(end, ':');
296 if (colon) {
297 *colon = 0;
298 *port = colon + 1;
302 static void enable_keepalive(int sockfd)
304 int ka = 1;
306 if (setsockopt(sockfd, SOL_SOCKET, SO_KEEPALIVE, &ka, sizeof(ka)) < 0)
307 fprintf(stderr, "unable to set SO_KEEPALIVE on socket: %s\n",
308 strerror(errno));
311 #ifndef NO_IPV6
313 static const char *ai_name(const struct addrinfo *ai)
315 static char addr[NI_MAXHOST];
316 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, addr, sizeof(addr), NULL, 0,
317 NI_NUMERICHOST) != 0)
318 strcpy(addr, "(unknown)");
320 return addr;
324 * Returns a connected socket() fd, or else die()s.
326 static int git_tcp_connect_sock(char *host, int flags)
328 struct strbuf error_message = STRBUF_INIT;
329 int sockfd = -1;
330 const char *port = STR(DEFAULT_GIT_PORT);
331 struct addrinfo hints, *ai0, *ai;
332 int gai;
333 int cnt = 0;
335 get_host_and_port(&host, &port);
336 if (!*port)
337 port = "<none>";
339 memset(&hints, 0, sizeof(hints));
340 hints.ai_socktype = SOCK_STREAM;
341 hints.ai_protocol = IPPROTO_TCP;
343 if (flags & CONNECT_VERBOSE)
344 fprintf(stderr, "Looking up %s ... ", host);
346 gai = getaddrinfo(host, port, &hints, &ai);
347 if (gai)
348 die("Unable to look up %s (port %s) (%s)", host, port, gai_strerror(gai));
350 if (flags & CONNECT_VERBOSE)
351 fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
353 for (ai0 = ai; ai; ai = ai->ai_next, cnt++) {
354 sockfd = socket(ai->ai_family,
355 ai->ai_socktype, ai->ai_protocol);
356 if ((sockfd < 0) ||
357 (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0)) {
358 strbuf_addf(&error_message, "%s[%d: %s]: errno=%s\n",
359 host, cnt, ai_name(ai), strerror(errno));
360 if (0 <= sockfd)
361 close(sockfd);
362 sockfd = -1;
363 continue;
365 if (flags & CONNECT_VERBOSE)
366 fprintf(stderr, "%s ", ai_name(ai));
367 break;
370 freeaddrinfo(ai0);
372 if (sockfd < 0)
373 die("unable to connect to %s:\n%s", host, error_message.buf);
375 enable_keepalive(sockfd);
377 if (flags & CONNECT_VERBOSE)
378 fprintf(stderr, "done.\n");
380 strbuf_release(&error_message);
382 return sockfd;
385 #else /* NO_IPV6 */
388 * Returns a connected socket() fd, or else die()s.
390 static int git_tcp_connect_sock(char *host, int flags)
392 struct strbuf error_message = STRBUF_INIT;
393 int sockfd = -1;
394 const char *port = STR(DEFAULT_GIT_PORT);
395 char *ep;
396 struct hostent *he;
397 struct sockaddr_in sa;
398 char **ap;
399 unsigned int nport;
400 int cnt;
402 get_host_and_port(&host, &port);
404 if (flags & CONNECT_VERBOSE)
405 fprintf(stderr, "Looking up %s ... ", host);
407 he = gethostbyname(host);
408 if (!he)
409 die("Unable to look up %s (%s)", host, hstrerror(h_errno));
410 nport = strtoul(port, &ep, 10);
411 if ( ep == port || *ep ) {
412 /* Not numeric */
413 struct servent *se = getservbyname(port,"tcp");
414 if ( !se )
415 die("Unknown port %s", port);
416 nport = se->s_port;
419 if (flags & CONNECT_VERBOSE)
420 fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
422 for (cnt = 0, ap = he->h_addr_list; *ap; ap++, cnt++) {
423 memset(&sa, 0, sizeof sa);
424 sa.sin_family = he->h_addrtype;
425 sa.sin_port = htons(nport);
426 memcpy(&sa.sin_addr, *ap, he->h_length);
428 sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
429 if ((sockfd < 0) ||
430 connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
431 strbuf_addf(&error_message, "%s[%d: %s]: errno=%s\n",
432 host,
433 cnt,
434 inet_ntoa(*(struct in_addr *)&sa.sin_addr),
435 strerror(errno));
436 if (0 <= sockfd)
437 close(sockfd);
438 sockfd = -1;
439 continue;
441 if (flags & CONNECT_VERBOSE)
442 fprintf(stderr, "%s ",
443 inet_ntoa(*(struct in_addr *)&sa.sin_addr));
444 break;
447 if (sockfd < 0)
448 die("unable to connect to %s:\n%s", host, error_message.buf);
450 enable_keepalive(sockfd);
452 if (flags & CONNECT_VERBOSE)
453 fprintf(stderr, "done.\n");
455 return sockfd;
458 #endif /* NO_IPV6 */
461 static void git_tcp_connect(int fd[2], char *host, int flags)
463 int sockfd = git_tcp_connect_sock(host, flags);
465 fd[0] = sockfd;
466 fd[1] = dup(sockfd);
470 static char *git_proxy_command;
472 static int git_proxy_command_options(const char *var, const char *value,
473 void *cb)
475 if (!strcmp(var, "core.gitproxy")) {
476 const char *for_pos;
477 int matchlen = -1;
478 int hostlen;
479 const char *rhost_name = cb;
480 int rhost_len = strlen(rhost_name);
482 if (git_proxy_command)
483 return 0;
484 if (!value)
485 return config_error_nonbool(var);
486 /* [core]
487 * ;# matches www.kernel.org as well
488 * gitproxy = netcatter-1 for kernel.org
489 * gitproxy = netcatter-2 for sample.xz
490 * gitproxy = netcatter-default
492 for_pos = strstr(value, " for ");
493 if (!for_pos)
494 /* matches everybody */
495 matchlen = strlen(value);
496 else {
497 hostlen = strlen(for_pos + 5);
498 if (rhost_len < hostlen)
499 matchlen = -1;
500 else if (!strncmp(for_pos + 5,
501 rhost_name + rhost_len - hostlen,
502 hostlen) &&
503 ((rhost_len == hostlen) ||
504 rhost_name[rhost_len - hostlen -1] == '.'))
505 matchlen = for_pos - value;
506 else
507 matchlen = -1;
509 if (0 <= matchlen) {
510 /* core.gitproxy = none for kernel.org */
511 if (matchlen == 4 &&
512 !memcmp(value, "none", 4))
513 matchlen = 0;
514 git_proxy_command = xmemdupz(value, matchlen);
516 return 0;
519 return git_default_config(var, value, cb);
522 static int git_use_proxy(const char *host)
524 git_proxy_command = getenv("GIT_PROXY_COMMAND");
525 git_config(git_proxy_command_options, (void*)host);
526 return (git_proxy_command && *git_proxy_command);
529 static struct child_process *git_proxy_connect(int fd[2], char *host)
531 const char *port = STR(DEFAULT_GIT_PORT);
532 struct child_process *proxy;
534 get_host_and_port(&host, &port);
536 proxy = xmalloc(sizeof(*proxy));
537 child_process_init(proxy);
538 argv_array_push(&proxy->args, git_proxy_command);
539 argv_array_push(&proxy->args, host);
540 argv_array_push(&proxy->args, port);
541 proxy->in = -1;
542 proxy->out = -1;
543 if (start_command(proxy))
544 die("cannot start proxy %s", git_proxy_command);
545 fd[0] = proxy->out; /* read from proxy stdout */
546 fd[1] = proxy->in; /* write to proxy stdin */
547 return proxy;
550 static const char *get_port_numeric(const char *p)
552 char *end;
553 if (p) {
554 long port = strtol(p + 1, &end, 10);
555 if (end != p + 1 && *end == '\0' && 0 <= port && port < 65536) {
556 return p;
560 return NULL;
564 * Extract protocol and relevant parts from the specified connection URL.
565 * The caller must free() the returned strings.
567 static enum protocol parse_connect_url(const char *url_orig, char **ret_host,
568 char **ret_path)
570 char *url;
571 char *host, *path;
572 char *end;
573 int separator = '/';
574 enum protocol protocol = PROTO_LOCAL;
576 if (is_url(url_orig))
577 url = url_decode(url_orig);
578 else
579 url = xstrdup(url_orig);
581 host = strstr(url, "://");
582 if (host) {
583 *host = '\0';
584 protocol = get_protocol(url);
585 host += 3;
586 } else {
587 host = url;
588 if (!url_is_local_not_ssh(url)) {
589 protocol = PROTO_SSH;
590 separator = ':';
595 * Don't do destructive transforms as protocol code does
596 * '[]' unwrapping in get_host_and_port()
598 if (host[0] == '[') {
599 end = strchr(host + 1, ']');
600 if (end) {
601 end++;
602 } else
603 end = host;
604 } else
605 end = host;
607 if (protocol == PROTO_LOCAL)
608 path = end;
609 else if (protocol == PROTO_FILE && has_dos_drive_prefix(end))
610 path = end; /* "file://$(pwd)" may be "file://C:/projects/repo" */
611 else
612 path = strchr(end, separator);
614 if (!path || !*path)
615 die("No path specified. See 'man git-pull' for valid url syntax");
618 * null-terminate hostname and point path to ~ for URL's like this:
619 * ssh://host.xz/~user/repo
622 end = path; /* Need to \0 terminate host here */
623 if (separator == ':')
624 path++; /* path starts after ':' */
625 if (protocol == PROTO_GIT || protocol == PROTO_SSH) {
626 if (path[1] == '~')
627 path++;
630 path = xstrdup(path);
631 *end = '\0';
633 *ret_host = xstrdup(host);
634 *ret_path = path;
635 free(url);
636 return protocol;
639 static struct child_process no_fork = CHILD_PROCESS_INIT;
642 * This returns a dummy child_process if the transport protocol does not
643 * need fork(2), or a struct child_process object if it does. Once done,
644 * finish the connection with finish_connect() with the value returned from
645 * this function (it is safe to call finish_connect() with NULL to support
646 * the former case).
648 * If it returns, the connect is successful; it just dies on errors (this
649 * will hopefully be changed in a libification effort, to return NULL when
650 * the connection failed).
652 struct child_process *git_connect(int fd[2], const char *url,
653 const char *prog, int flags)
655 char *hostandport, *path;
656 struct child_process *conn = &no_fork;
657 enum protocol protocol;
658 struct strbuf cmd = STRBUF_INIT;
660 /* Without this we cannot rely on waitpid() to tell
661 * what happened to our children.
663 signal(SIGCHLD, SIG_DFL);
665 protocol = parse_connect_url(url, &hostandport, &path);
666 if (flags & CONNECT_DIAG_URL) {
667 printf("Diag: url=%s\n", url ? url : "NULL");
668 printf("Diag: protocol=%s\n", prot_name(protocol));
669 printf("Diag: hostandport=%s\n", hostandport ? hostandport : "NULL");
670 printf("Diag: path=%s\n", path ? path : "NULL");
671 conn = NULL;
672 } else if (protocol == PROTO_GIT) {
673 /* These underlying connection commands die() if they
674 * cannot connect.
676 char *target_host = xstrdup(hostandport);
677 if (git_use_proxy(hostandport))
678 conn = git_proxy_connect(fd, hostandport);
679 else
680 git_tcp_connect(fd, hostandport, flags);
682 * Separate original protocol components prog and path
683 * from extended host header with a NUL byte.
685 * Note: Do not add any other headers here! Doing so
686 * will cause older git-daemon servers to crash.
688 packet_write(fd[1],
689 "%s %s%chost=%s%c",
690 prog, path, 0,
691 target_host, 0);
692 free(target_host);
693 } else {
694 conn = xmalloc(sizeof(*conn));
695 child_process_init(conn);
697 strbuf_addstr(&cmd, prog);
698 strbuf_addch(&cmd, ' ');
699 sq_quote_buf(&cmd, path);
701 conn->in = conn->out = -1;
702 if (protocol == PROTO_SSH) {
703 const char *ssh = getenv("GIT_SSH");
704 int putty = ssh && strcasestr(ssh, "plink");
705 char *ssh_host = hostandport;
706 const char *port = NULL;
707 get_host_and_port(&ssh_host, &port);
708 port = get_port_numeric(port);
710 if (!ssh) ssh = "ssh";
712 argv_array_push(&conn->args, ssh);
713 if (putty && !strcasestr(ssh, "tortoiseplink"))
714 argv_array_push(&conn->args, "-batch");
715 if (port) {
716 /* P is for PuTTY, p is for OpenSSH */
717 argv_array_push(&conn->args, putty ? "-P" : "-p");
718 argv_array_push(&conn->args, port);
720 argv_array_push(&conn->args, ssh_host);
721 } else {
722 /* remove repo-local variables from the environment */
723 conn->env = local_repo_env;
724 conn->use_shell = 1;
726 argv_array_push(&conn->args, cmd.buf);
728 if (start_command(conn))
729 die("unable to fork");
731 fd[0] = conn->out; /* read from child's stdout */
732 fd[1] = conn->in; /* write to child's stdin */
733 strbuf_release(&cmd);
735 free(hostandport);
736 free(path);
737 return conn;
740 int git_connection_is_socket(struct child_process *conn)
742 return conn == &no_fork;
745 int finish_connect(struct child_process *conn)
747 int code;
748 if (!conn || git_connection_is_socket(conn))
749 return 0;
751 code = finish_command(conn);
752 free(conn);
753 return code;