1#include "cache.h"
2#include "refs.h"
3#include "pkt-line.h"
4#include <sys/wait.h>
5
6static int quiet;
7static int keep_pack;
8static const char clone_pack_usage[] = "git-clone-pack [-q] [--exec=<git-upload-pack>] [<host>:]<directory> [<heads>]*";
9static const char *exec = "git-upload-pack";
10
11static void clone_handshake(int fd[2], struct ref *ref)
12{
13 unsigned char sha1[20];
14
15 while (ref) {
16 packet_write(fd[1], "want %s\n", sha1_to_hex(ref->old_sha1));
17 ref = ref->next;
18 }
19 packet_flush(fd[1]);
20
21 /* We don't have nuttin' */
22 packet_write(fd[1], "done\n");
23 if (get_ack(fd[0], sha1))
24 error("Huh! git-clone-pack got positive ack for %s", sha1_to_hex(sha1));
25}
26
27static int is_master(struct ref *ref)
28{
29 return !strcmp(ref->name, "refs/heads/master");
30}
31
32static void write_one_ref(struct ref *ref)
33{
34 char *path = git_path("%s", ref->name);
35 int fd;
36 char *hex;
37
38 if (safe_create_leading_directories(path))
39 die("unable to create leading directory for %s", ref->name);
40 fd = open(path, O_CREAT | O_EXCL | O_WRONLY, 0666);
41 if (fd < 0)
42 die("unable to create ref %s", ref->name);
43 hex = sha1_to_hex(ref->old_sha1);
44 hex[40] = '\n';
45 if (write(fd, hex, 41) != 41)
46 die("unable to write ref %s", ref->name);
47 close(fd);
48}
49
50static void write_refs(struct ref *ref)
51{
52 struct ref *head = NULL, *head_ptr, *master_ref;
53 char *head_path;
54
55 /* Upload-pack must report HEAD first */
56 if (!strcmp(ref->name, "HEAD")) {
57 head = ref;
58 ref = ref->next;
59 }
60 head_ptr = NULL;
61 master_ref = NULL;
62 while (ref) {
63 if (is_master(ref))
64 master_ref = ref;
65 if (head &&
66 !memcmp(ref->old_sha1, head->old_sha1, 20) &&
67 !strncmp(ref->name, "refs/heads/",11) &&
68 (!head_ptr || ref == master_ref))
69 head_ptr = ref;
70
71 write_one_ref(ref);
72 ref = ref->next;
73 }
74 if (!head) {
75 fprintf(stderr, "No HEAD in remote.\n");
76 return;
77 }
78
79 head_path = strdup(git_path("HEAD"));
80 if (!head_ptr) {
81 /*
82 * If we had a master ref, and it wasn't HEAD, we need to undo the
83 * symlink, and write a standalone HEAD. Give a warning, because that's
84 * really really wrong.
85 */
86 if (master_ref) {
87 error("HEAD doesn't point to any refs! Making standalone HEAD");
88 unlink(head_path);
89 }
90 write_one_ref(head);
91 free(head_path);
92 return;
93 }
94
95 /* We reset to the master branch if it's available */
96 if (master_ref)
97 return;
98
99 fprintf(stderr, "Setting HEAD to %s\n", head_ptr->name);
100
101 /*
102 * Uhhuh. Other end didn't have master. We start HEAD off with
103 * the first branch with the same value.
104 */
105 if (create_symref(head_path, head_ptr->name) < 0)
106 die("unable to link HEAD to %s", head_ptr->name);
107 free(head_path);
108}
109
110static int clone_by_unpack(int fd[2])
111{
112 int status;
113 pid_t pid;
114
115 pid = fork();
116 if (pid < 0)
117 die("git-clone-pack: unable to fork off git-unpack-objects");
118 if (!pid) {
119 dup2(fd[0], 0);
120 close(fd[0]);
121 close(fd[1]);
122 execlp("git-unpack-objects", "git-unpack-objects",
123 quiet ? "-q" : NULL, NULL);
124 die("git-unpack-objects exec failed");
125 }
126 close(fd[0]);
127 close(fd[1]);
128 while (waitpid(pid, &status, 0) < 0) {
129 if (errno != EINTR)
130 die("waiting for git-unpack-objects: %s", strerror(errno));
131 }
132 if (WIFEXITED(status)) {
133 int code = WEXITSTATUS(status);
134 if (code)
135 die("git-unpack-objects died with error code %d", code);
136 return 0;
137 }
138 if (WIFSIGNALED(status)) {
139 int sig = WTERMSIG(status);
140 die("git-unpack-objects died of signal %d", sig);
141 }
142 die("Sherlock Holmes! git-unpack-objects died of unnatural causes %d!", status);
143}
144
145static int finish_pack(const char *pack_tmp_name)
146{
147 int pipe_fd[2];
148 pid_t pid;
149 char idx[PATH_MAX];
150 char final[PATH_MAX];
151 char hash[41];
152 unsigned char sha1[20];
153 char *cp;
154 int err = 0;
155
156 if (pipe(pipe_fd) < 0)
157 die("git-clone-pack: unable to set up pipe");
158
159 strcpy(idx, pack_tmp_name); /* ".git/objects/pack-XXXXXX" */
160 cp = strrchr(idx, '/');
161 memcpy(cp, "/pidx", 5);
162
163 pid = fork();
164 if (pid < 0)
165 die("git-clone-pack: unable to fork off git-index-pack");
166 if (!pid) {
167 close(0);
168 dup2(pipe_fd[1], 1);
169 close(pipe_fd[0]);
170 close(pipe_fd[1]);
171 execlp("git-index-pack","git-index-pack",
172 "-o", idx, pack_tmp_name, NULL);
173 error("cannot exec git-index-pack <%s> <%s>",
174 idx, pack_tmp_name);
175 exit(1);
176 }
177 close(pipe_fd[1]);
178 if (read(pipe_fd[0], hash, 40) != 40) {
179 error("git-clone-pack: unable to read from git-index-pack");
180 err = 1;
181 }
182 close(pipe_fd[0]);
183
184 for (;;) {
185 int status, code;
186 int retval = waitpid(pid, &status, 0);
187
188 if (retval < 0) {
189 if (errno == EINTR)
190 continue;
191 error("waitpid failed (%s)", strerror(retval));
192 goto error_die;
193 }
194 if (WIFSIGNALED(status)) {
195 int sig = WTERMSIG(status);
196 error("git-index-pack died of signal %d", sig);
197 goto error_die;
198 }
199 if (!WIFEXITED(status)) {
200 error("git-index-pack died of unnatural causes %d",
201 status);
202 goto error_die;
203 }
204 code = WEXITSTATUS(status);
205 if (code) {
206 error("git-index-pack died with error code %d", code);
207 goto error_die;
208 }
209 if (err)
210 goto error_die;
211 break;
212 }
213 hash[40] = 0;
214 if (get_sha1_hex(hash, sha1)) {
215 error("git-index-pack reported nonsense '%s'", hash);
216 goto error_die;
217 }
218 /* Now we have pack in pack_tmp_name[], and
219 * idx in idx[]; rename them to their final names.
220 */
221 snprintf(final, sizeof(final),
222 "%s/pack/pack-%s.pack", get_object_directory(), hash);
223 move_temp_to_file(pack_tmp_name, final);
224 snprintf(final, sizeof(final),
225 "%s/pack/pack-%s.idx", get_object_directory(), hash);
226 move_temp_to_file(idx, final);
227 return 0;
228
229 error_die:
230 unlink(idx);
231 unlink(pack_tmp_name);
232 exit(1);
233}
234
235static int clone_without_unpack(int fd[2])
236{
237 char tmpfile[PATH_MAX];
238 int ofd, ifd;
239
240 ifd = fd[0];
241 snprintf(tmpfile, sizeof(tmpfile),
242 "%s/pack-XXXXXX", get_object_directory());
243 ofd = mkstemp(tmpfile);
244 if (ofd < 0)
245 return error("unable to create temporary file %s", tmpfile);
246
247 while (1) {
248 char buf[8192];
249 ssize_t sz, wsz, pos;
250 sz = read(ifd, buf, sizeof(buf));
251 if (sz == 0)
252 break;
253 if (sz < 0) {
254 error("error reading pack (%s)", strerror(errno));
255 close(ofd);
256 unlink(tmpfile);
257 return -1;
258 }
259 pos = 0;
260 while (pos < sz) {
261 wsz = write(ofd, buf + pos, sz - pos);
262 if (wsz < 0) {
263 error("error writing pack (%s)",
264 strerror(errno));
265 close(ofd);
266 unlink(tmpfile);
267 return -1;
268 }
269 pos += wsz;
270 }
271 }
272 close(ofd);
273 return finish_pack(tmpfile);
274}
275
276static int clone_pack(int fd[2], int nr_match, char **match)
277{
278 struct ref *refs;
279 int status;
280
281 get_remote_heads(fd[0], &refs, nr_match, match);
282 if (!refs) {
283 packet_flush(fd[1]);
284 die("no matching remote head");
285 }
286 clone_handshake(fd, refs);
287
288 if (keep_pack)
289 status = clone_without_unpack(fd);
290 else
291 status = clone_by_unpack(fd);
292
293 if (!status)
294 write_refs(refs);
295 return status;
296}
297
298static int clone_options(const char *var, const char *value)
299{
300 if (!strcmp("clone.keeppack", var)) {
301 keep_pack = git_config_bool(var, value);
302 return 0;
303 }
304 if (!strcmp("clone.quiet", var)) {
305 quiet = git_config_bool(var, value);
306 return 0;
307 }
308 /*
309 * Put other local option parsing for this program
310 * here ...
311 */
312
313 /* Fall back on the default ones */
314 return git_default_config(var, value);
315}
316
317int main(int argc, char **argv)
318{
319 int i, ret, nr_heads;
320 char *dest = NULL, **heads;
321 int fd[2];
322 pid_t pid;
323
324 git_config(clone_options);
325 nr_heads = 0;
326 heads = NULL;
327 for (i = 1; i < argc; i++) {
328 char *arg = argv[i];
329
330 if (*arg == '-') {
331 if (!strcmp("-q", arg)) {
332 quiet = 1;
333 continue;
334 }
335 if (!strncmp("--exec=", arg, 7)) {
336 exec = arg + 7;
337 continue;
338 }
339 if (!strcmp("--keep", arg)) {
340 keep_pack = 1;
341 continue;
342 }
343 usage(clone_pack_usage);
344 }
345 dest = arg;
346 heads = argv + i + 1;
347 nr_heads = argc - i - 1;
348 break;
349 }
350 if (!dest)
351 usage(clone_pack_usage);
352 pid = git_connect(fd, dest, exec);
353 if (pid < 0)
354 return 1;
355 ret = clone_pack(fd, nr_heads, heads);
356 close(fd[0]);
357 close(fd[1]);
358 finish_connect(pid);
359 return ret;
360}