1#include <signal.h>
2#include <sys/wait.h>
3#include <sys/poll.h>
4#include "cache.h"
5#include "refs.h"
6#include "pkt-line.h"
7#include "tag.h"
8#include "object.h"
9#include "commit.h"
10#include "exec_cmd.h"
11static const char upload_pack_usage[] = "git-upload-pack [--strict] [--timeout=nn] <dir>";
13#define THEY_HAVE (1U << 0)
15#define OUR_REF (1U << 1)
16#define WANTED (1U << 2)
17#define MAX_HAS 256
18#define MAX_NEEDS 256
19static int nr_has = 0, nr_needs = 0, multi_ack = 0, nr_our_refs = 0;
20static int use_thin_pack = 0;
21static unsigned char has_sha1[MAX_HAS][20];
22static unsigned char needs_sha1[MAX_NEEDS][20];
23static unsigned int timeout = 0;
24static int use_sideband = 0;
25static void reset_timeout(void)
27{
28 alarm(timeout);
29}
30static int strip(char *line, int len)
32{
33 if (len && line[len-1] == '\n')
34 line[--len] = 0;
35 return len;
36}
37#define PACKET_MAX 1000
39static ssize_t send_client_data(int fd, const char *data, ssize_t sz)
40{
41 ssize_t ssz;
42 const char *p;
43 if (!data) {
45 if (!use_sideband)
46 return 0;
47 packet_flush(1);
48 }
49 if (!use_sideband) {
51 if (fd == 3)
52 /* emergency quit */
53 fd = 2;
54 if (fd == 2) {
55 xwrite(fd, data, sz);
56 return sz;
57 }
58 return safe_write(fd, data, sz);
59 }
60 p = data;
61 ssz = sz;
62 while (sz) {
63 unsigned n;
64 char hdr[5];
65 n = sz;
67 if (PACKET_MAX - 5 < n)
68 n = PACKET_MAX - 5;
69 sprintf(hdr, "%04x", n + 5);
70 hdr[4] = fd;
71 safe_write(1, hdr, 5);
72 safe_write(1, p, n);
73 p += n;
74 sz -= n;
75 }
76 return ssz;
77}
78static void create_pack_file(void)
80{
81 /* Pipes between rev-list to pack-objects, pack-objects to us
82 * and pack-objects error stream for progress bar.
83 */
84 int lp_pipe[2], pu_pipe[2], pe_pipe[2];
85 pid_t pid_rev_list, pid_pack_objects;
86 int create_full_pack = (nr_our_refs == nr_needs && !nr_has);
87 char data[8193], progress[128];
88 char abort_msg[] = "aborting due to possible repository "
89 "corruption on the remote side.";
90 int buffered = -1;
91 if (pipe(lp_pipe) < 0)
93 die("git-upload-pack: unable to create pipe");
94 pid_rev_list = fork();
95 if (pid_rev_list < 0)
96 die("git-upload-pack: unable to fork git-rev-list");
97 if (!pid_rev_list) {
99 int i;
100 int args;
101 const char **argv;
102 const char **p;
103 char *buf;
104 if (create_full_pack) {
106 args = 10;
107 use_thin_pack = 0; /* no point doing it */
108 }
109 else
110 args = nr_has + nr_needs + 5;
111 p = xmalloc(args * sizeof(char *));
112 argv = (const char **) p;
113 buf = xmalloc(args * 45);
114 dup2(lp_pipe[1], 1);
116 close(0);
117 close(lp_pipe[0]);
118 close(lp_pipe[1]);
119 *p++ = "rev-list";
120 *p++ = use_thin_pack ? "--objects-edge" : "--objects";
121 if (create_full_pack || MAX_NEEDS <= nr_needs)
122 *p++ = "--all";
123 else {
124 for (i = 0; i < nr_needs; i++) {
125 *p++ = buf;
126 memcpy(buf, sha1_to_hex(needs_sha1[i]), 41);
127 buf += 41;
128 }
129 }
130 if (!create_full_pack)
131 for (i = 0; i < nr_has; i++) {
132 *p++ = buf;
133 *buf++ = '^';
134 memcpy(buf, sha1_to_hex(has_sha1[i]), 41);
135 buf += 41;
136 }
137 *p++ = NULL;
138 execv_git_cmd(argv);
139 die("git-upload-pack: unable to exec git-rev-list");
140 }
141 if (pipe(pu_pipe) < 0)
143 die("git-upload-pack: unable to create pipe");
144 if (pipe(pe_pipe) < 0)
145 die("git-upload-pack: unable to create pipe");
146 pid_pack_objects = fork();
147 if (pid_pack_objects < 0) {
148 /* daemon sets things up to ignore TERM */
149 kill(pid_rev_list, SIGKILL);
150 die("git-upload-pack: unable to fork git-pack-objects");
151 }
152 if (!pid_pack_objects) {
153 dup2(lp_pipe[0], 0);
154 dup2(pu_pipe[1], 1);
155 dup2(pe_pipe[1], 2);
156 close(lp_pipe[0]);
158 close(lp_pipe[1]);
159 close(pu_pipe[0]);
160 close(pu_pipe[1]);
161 close(pe_pipe[0]);
162 close(pe_pipe[1]);
163 execl_git_cmd("pack-objects", "--stdout", "--progress", NULL);
164 kill(pid_rev_list, SIGKILL);
165 die("git-upload-pack: unable to exec git-pack-objects");
166 }
167 close(lp_pipe[0]);
169 close(lp_pipe[1]);
170 /* We read from pe_pipe[0] to capture stderr output for
172 * progress bar, and pu_pipe[0] to capture the pack data.
173 */
174 close(pe_pipe[1]);
175 close(pu_pipe[1]);
176 while (1) {
178 const char *who;
179 struct pollfd pfd[2];
180 pid_t pid;
181 int status;
182 ssize_t sz;
183 int pe, pu, pollsize;
184 pollsize = 0;
186 pe = pu = -1;
187 if (0 <= pu_pipe[0]) {
189 pfd[pollsize].fd = pu_pipe[0];
190 pfd[pollsize].events = POLLIN;
191 pu = pollsize;
192 pollsize++;
193 }
194 if (0 <= pe_pipe[0]) {
195 pfd[pollsize].fd = pe_pipe[0];
196 pfd[pollsize].events = POLLIN;
197 pe = pollsize;
198 pollsize++;
199 }
200 if (pollsize) {
202 if (poll(pfd, pollsize, -1) < 0) {
203 if (errno != EINTR) {
204 error("poll failed, resuming: %s",
205 strerror(errno));
206 sleep(1);
207 }
208 continue;
209 }
210 if (0 <= pu && (pfd[pu].revents & (POLLIN|POLLHUP))) {
211 /* Data ready; we keep the last byte
212 * to ourselves in case we detect
213 * broken rev-list, so that we can
214 * leave the stream corrupted. This
215 * is unfortunate -- unpack-objects
216 * would happily accept a valid pack
217 * data with trailing garbage, so
218 * appending garbage after we pass all
219 * the pack data is not good enough to
220 * signal breakage to downstream.
221 */
222 char *cp = data;
223 ssize_t outsz = 0;
224 if (0 <= buffered) {
225 *cp++ = buffered;
226 outsz++;
227 }
228 sz = read(pu_pipe[0], cp,
229 sizeof(data) - outsz);
230 if (0 < sz)
231 ;
232 else if (sz == 0) {
233 close(pu_pipe[0]);
234 pu_pipe[0] = -1;
235 }
236 else
237 goto fail;
238 sz += outsz;
239 if (1 < sz) {
240 buffered = data[sz-1] & 0xFF;
241 sz--;
242 }
243 else
244 buffered = -1;
245 sz = send_client_data(1, data, sz);
246 if (sz < 0)
247 goto fail;
248 }
249 if (0 <= pe && (pfd[pe].revents & (POLLIN|POLLHUP))) {
250 /* Status ready; we ship that in the side-band
251 * or dump to the standard error.
252 */
253 sz = read(pe_pipe[0], progress,
254 sizeof(progress));
255 if (0 < sz)
256 send_client_data(2, progress, sz);
257 else if (sz == 0) {
258 close(pe_pipe[0]);
259 pe_pipe[0] = -1;
260 }
261 else
262 goto fail;
263 }
264 }
265 /* See if the children are still there */
267 if (pid_rev_list || pid_pack_objects) {
268 pid = waitpid(-1, &status, WNOHANG);
269 if (!pid)
270 continue;
271 who = ((pid == pid_rev_list) ? "git-rev-list" :
272 (pid == pid_pack_objects) ? "git-pack-objects" :
273 NULL);
274 if (!who) {
275 if (pid < 0) {
276 error("git-upload-pack: %s",
277 strerror(errno));
278 goto fail;
279 }
280 error("git-upload-pack: we weren't "
281 "waiting for %d", pid);
282 continue;
283 }
284 if (!WIFEXITED(status) || WEXITSTATUS(status) > 0) {
285 error("git-upload-pack: %s died with error.",
286 who);
287 goto fail;
288 }
289 if (pid == pid_rev_list)
290 pid_rev_list = 0;
291 if (pid == pid_pack_objects)
292 pid_pack_objects = 0;
293 if (pid_rev_list || pid_pack_objects)
294 continue;
295 }
296 /* both died happily */
298 if (pollsize)
299 continue;
300 /* flush the data */
302 if (0 <= buffered) {
303 data[0] = buffered;
304 sz = send_client_data(1, data, 1);
305 if (sz < 0)
306 goto fail;
307 fprintf(stderr, "flushed.\n");
308 }
309 send_client_data(1, NULL, 0);
310 return;
311 }
312 fail:
313 if (pid_pack_objects)
314 kill(pid_pack_objects, SIGKILL);
315 if (pid_rev_list)
316 kill(pid_rev_list, SIGKILL);
317 send_client_data(3, abort_msg, sizeof(abort_msg));
318 die("git-upload-pack: %s", abort_msg);
319}
320static int got_sha1(char *hex, unsigned char *sha1)
322{
323 if (get_sha1_hex(hex, sha1))
324 die("git-upload-pack: expected SHA1 object, got '%s'", hex);
325 if (!has_sha1_file(sha1))
326 return 0;
327 if (nr_has < MAX_HAS) {
328 struct object *o = lookup_object(sha1);
329 if (!(o && o->parsed))
330 o = parse_object(sha1);
331 if (!o)
332 die("oops (%s)", sha1_to_hex(sha1));
333 if (o->type == TYPE_COMMIT) {
334 struct commit_list *parents;
335 if (o->flags & THEY_HAVE)
336 return 0;
337 o->flags |= THEY_HAVE;
338 for (parents = ((struct commit*)o)->parents;
339 parents;
340 parents = parents->next)
341 parents->item->object.flags |= THEY_HAVE;
342 }
343 memcpy(has_sha1[nr_has++], sha1, 20);
344 }
345 return 1;
346}
347static int get_common_commits(void)
349{
350 static char line[1000];
351 unsigned char sha1[20], last_sha1[20];
352 int len;
353 track_object_refs = 0;
355 save_commit_buffer = 0;
356 for(;;) {
358 len = packet_read_line(0, line, sizeof(line));
359 reset_timeout();
360 if (!len) {
362 if (nr_has == 0 || multi_ack)
363 packet_write(1, "NAK\n");
364 continue;
365 }
366 len = strip(line, len);
367 if (!strncmp(line, "have ", 5)) {
368 if (got_sha1(line+5, sha1) &&
369 (multi_ack || nr_has == 1)) {
370 if (nr_has >= MAX_HAS)
371 multi_ack = 0;
372 packet_write(1, "ACK %s%s\n",
373 sha1_to_hex(sha1),
374 multi_ack ? " continue" : "");
375 if (multi_ack)
376 memcpy(last_sha1, sha1, 20);
377 }
378 continue;
379 }
380 if (!strcmp(line, "done")) {
381 if (nr_has > 0) {
382 if (multi_ack)
383 packet_write(1, "ACK %s\n",
384 sha1_to_hex(last_sha1));
385 return 0;
386 }
387 packet_write(1, "NAK\n");
388 return -1;
389 }
390 die("git-upload-pack: expected SHA1 list, got '%s'", line);
391 }
392}
393static int receive_needs(void)
395{
396 static char line[1000];
397 int len, needs;
398 needs = 0;
400 for (;;) {
401 struct object *o;
402 unsigned char dummy[20], *sha1_buf;
403 len = packet_read_line(0, line, sizeof(line));
404 reset_timeout();
405 if (!len)
406 return needs;
407 sha1_buf = dummy;
409 if (needs == MAX_NEEDS) {
410 fprintf(stderr,
411 "warning: supporting only a max of %d requests. "
412 "sending everything instead.\n",
413 MAX_NEEDS);
414 }
415 else if (needs < MAX_NEEDS)
416 sha1_buf = needs_sha1[needs];
417 if (strncmp("want ", line, 5) || get_sha1_hex(line+5, sha1_buf))
419 die("git-upload-pack: protocol error, "
420 "expected to get sha, not '%s'", line);
421 if (strstr(line+45, "multi_ack"))
422 multi_ack = 1;
423 if (strstr(line+45, "thin-pack"))
424 use_thin_pack = 1;
425 if (strstr(line+45, "side-band"))
426 use_sideband = 1;
427 /* We have sent all our refs already, and the other end
429 * should have chosen out of them; otherwise they are
430 * asking for nonsense.
431 *
432 * Hmph. We may later want to allow "want" line that
433 * asks for something like "master~10" (symbolic)...
434 * would it make sense? I don't know.
435 */
436 o = lookup_object(sha1_buf);
437 if (!o || !(o->flags & OUR_REF))
438 die("git-upload-pack: not our ref %s", line+5);
439 if (!(o->flags & WANTED)) {
440 o->flags |= WANTED;
441 needs++;
442 }
443 }
444}
445static int send_ref(const char *refname, const unsigned char *sha1)
447{
448 static const char *capabilities = "multi_ack thin-pack side-band";
449 struct object *o = parse_object(sha1);
450 if (!o)
452 die("git-upload-pack: cannot find object %s:", sha1_to_hex(sha1));
453 if (capabilities)
455 packet_write(1, "%s %s%c%s\n", sha1_to_hex(sha1), refname,
456 0, capabilities);
457 else
458 packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname);
459 capabilities = NULL;
460 if (!(o->flags & OUR_REF)) {
461 o->flags |= OUR_REF;
462 nr_our_refs++;
463 }
464 if (o->type == TYPE_TAG) {
465 o = deref_tag(o, refname, 0);
466 packet_write(1, "%s %s^{}\n", sha1_to_hex(o->sha1), refname);
467 }
468 return 0;
469}
470static int upload_pack(void)
472{
473 reset_timeout();
474 head_ref(send_ref);
475 for_each_ref(send_ref);
476 packet_flush(1);
477 nr_needs = receive_needs();
478 if (!nr_needs)
479 return 0;
480 get_common_commits();
481 create_pack_file();
482 return 0;
483}
484int main(int argc, char **argv)
486{
487 char *dir;
488 int i;
489 int strict = 0;
490 for (i = 1; i < argc; i++) {
492 char *arg = argv[i];
493 if (arg[0] != '-')
495 break;
496 if (!strcmp(arg, "--strict")) {
497 strict = 1;
498 continue;
499 }
500 if (!strncmp(arg, "--timeout=", 10)) {
501 timeout = atoi(arg+10);
502 continue;
503 }
504 if (!strcmp(arg, "--")) {
505 i++;
506 break;
507 }
508 }
509
510 if (i != argc-1)
511 usage(upload_pack_usage);
512 dir = argv[i];
513 if (!enter_repo(dir, strict))
515 die("'%s': unable to chdir or not a git archive", dir);
516 upload_pack();
518 return 0;
519}