send-pack: refactor decision to send update per ref
[git] / send-pack.c
1 #include "builtin.h"
2 #include "commit.h"
3 #include "refs.h"
4 #include "pkt-line.h"
5 #include "sideband.h"
6 #include "run-command.h"
7 #include "remote.h"
8 #include "connect.h"
9 #include "send-pack.h"
10 #include "quote.h"
11 #include "transport.h"
12 #include "version.h"
13 #include "sha1-array.h"
14
15 static int feed_object(const unsigned char *sha1, int fd, int negative)
16 {
17         char buf[42];
18
19         if (negative && !has_sha1_file(sha1))
20                 return 1;
21
22         memcpy(buf + negative, sha1_to_hex(sha1), 40);
23         if (negative)
24                 buf[0] = '^';
25         buf[40 + negative] = '\n';
26         return write_or_whine(fd, buf, 41 + negative, "send-pack: send refs");
27 }
28
29 /*
30  * Make a pack stream and spit it out into file descriptor fd
31  */
32 static int pack_objects(int fd, struct ref *refs, struct sha1_array *extra, struct send_pack_args *args)
33 {
34         /*
35          * The child becomes pack-objects --revs; we feed
36          * the revision parameters to it via its stdin and
37          * let its stdout go back to the other end.
38          */
39         const char *argv[] = {
40                 "pack-objects",
41                 "--all-progress-implied",
42                 "--revs",
43                 "--stdout",
44                 NULL,
45                 NULL,
46                 NULL,
47                 NULL,
48                 NULL,
49         };
50         struct child_process po;
51         int i;
52
53         i = 4;
54         if (args->use_thin_pack)
55                 argv[i++] = "--thin";
56         if (args->use_ofs_delta)
57                 argv[i++] = "--delta-base-offset";
58         if (args->quiet || !args->progress)
59                 argv[i++] = "-q";
60         if (args->progress)
61                 argv[i++] = "--progress";
62         memset(&po, 0, sizeof(po));
63         po.argv = argv;
64         po.in = -1;
65         po.out = args->stateless_rpc ? -1 : fd;
66         po.git_cmd = 1;
67         if (start_command(&po))
68                 die_errno("git pack-objects failed");
69
70         /*
71          * We feed the pack-objects we just spawned with revision
72          * parameters by writing to the pipe.
73          */
74         for (i = 0; i < extra->nr; i++)
75                 if (!feed_object(extra->sha1[i], po.in, 1))
76                         break;
77
78         while (refs) {
79                 if (!is_null_sha1(refs->old_sha1) &&
80                     !feed_object(refs->old_sha1, po.in, 1))
81                         break;
82                 if (!is_null_sha1(refs->new_sha1) &&
83                     !feed_object(refs->new_sha1, po.in, 0))
84                         break;
85                 refs = refs->next;
86         }
87
88         close(po.in);
89
90         if (args->stateless_rpc) {
91                 char *buf = xmalloc(LARGE_PACKET_MAX);
92                 while (1) {
93                         ssize_t n = xread(po.out, buf, LARGE_PACKET_MAX);
94                         if (n <= 0)
95                                 break;
96                         send_sideband(fd, -1, buf, n, LARGE_PACKET_MAX);
97                 }
98                 free(buf);
99                 close(po.out);
100                 po.out = -1;
101         }
102
103         if (finish_command(&po))
104                 return -1;
105         return 0;
106 }
107
108 static int receive_status(int in, struct ref *refs)
109 {
110         struct ref *hint;
111         int ret = 0;
112         char *line = packet_read_line(in, NULL);
113         if (!starts_with(line, "unpack "))
114                 return error("did not receive remote status");
115         if (strcmp(line, "unpack ok")) {
116                 error("unpack failed: %s", line + 7);
117                 ret = -1;
118         }
119         hint = NULL;
120         while (1) {
121                 char *refname;
122                 char *msg;
123                 line = packet_read_line(in, NULL);
124                 if (!line)
125                         break;
126                 if (!starts_with(line, "ok ") && !starts_with(line, "ng ")) {
127                         error("invalid ref status from remote: %s", line);
128                         ret = -1;
129                         break;
130                 }
131
132                 refname = line + 3;
133                 msg = strchr(refname, ' ');
134                 if (msg)
135                         *msg++ = '\0';
136
137                 /* first try searching at our hint, falling back to all refs */
138                 if (hint)
139                         hint = find_ref_by_name(hint, refname);
140                 if (!hint)
141                         hint = find_ref_by_name(refs, refname);
142                 if (!hint) {
143                         warning("remote reported status on unknown ref: %s",
144                                         refname);
145                         continue;
146                 }
147                 if (hint->status != REF_STATUS_EXPECTING_REPORT) {
148                         warning("remote reported status on unexpected ref: %s",
149                                         refname);
150                         continue;
151                 }
152
153                 if (line[0] == 'o' && line[1] == 'k')
154                         hint->status = REF_STATUS_OK;
155                 else {
156                         hint->status = REF_STATUS_REMOTE_REJECT;
157                         ret = -1;
158                 }
159                 if (msg)
160                         hint->remote_status = xstrdup(msg);
161                 /* start our next search from the next ref */
162                 hint = hint->next;
163         }
164         return ret;
165 }
166
167 static int sideband_demux(int in, int out, void *data)
168 {
169         int *fd = data, ret;
170 #ifdef NO_PTHREADS
171         close(fd[1]);
172 #endif
173         ret = recv_sideband("send-pack", fd[0], out);
174         close(out);
175         return ret;
176 }
177
178 static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
179 {
180         struct strbuf *sb = cb;
181         if (graft->nr_parent == -1)
182                 packet_buf_write(sb, "shallow %s\n", sha1_to_hex(graft->sha1));
183         return 0;
184 }
185
186 static void advertise_shallow_grafts_buf(struct strbuf *sb)
187 {
188         if (!is_repository_shallow())
189                 return;
190         for_each_commit_graft(advertise_shallow_grafts_cb, sb);
191 }
192
193 static int ref_update_to_be_sent(const struct ref *ref, const struct send_pack_args *args)
194 {
195         if (!ref->peer_ref && !args->send_mirror)
196                 return 0;
197
198         /* Check for statuses set by set_ref_status_for_push() */
199         switch (ref->status) {
200         case REF_STATUS_REJECT_NONFASTFORWARD:
201         case REF_STATUS_REJECT_ALREADY_EXISTS:
202         case REF_STATUS_REJECT_FETCH_FIRST:
203         case REF_STATUS_REJECT_NEEDS_FORCE:
204         case REF_STATUS_REJECT_STALE:
205         case REF_STATUS_REJECT_NODELETE:
206         case REF_STATUS_UPTODATE:
207                 return 0;
208         default:
209                 return 1;
210         }
211 }
212
213 int send_pack(struct send_pack_args *args,
214               int fd[], struct child_process *conn,
215               struct ref *remote_refs,
216               struct sha1_array *extra_have)
217 {
218         int in = fd[0];
219         int out = fd[1];
220         struct strbuf req_buf = STRBUF_INIT;
221         struct ref *ref;
222         int new_refs;
223         int allow_deleting_refs = 0;
224         int status_report = 0;
225         int use_sideband = 0;
226         int quiet_supported = 0;
227         int agent_supported = 0;
228         unsigned cmds_sent = 0;
229         int ret;
230         struct async demux;
231
232         /* Does the other end support the reporting? */
233         if (server_supports("report-status"))
234                 status_report = 1;
235         if (server_supports("delete-refs"))
236                 allow_deleting_refs = 1;
237         if (server_supports("ofs-delta"))
238                 args->use_ofs_delta = 1;
239         if (server_supports("side-band-64k"))
240                 use_sideband = 1;
241         if (server_supports("quiet"))
242                 quiet_supported = 1;
243         if (server_supports("agent"))
244                 agent_supported = 1;
245         if (server_supports("no-thin"))
246                 args->use_thin_pack = 0;
247
248         if (!remote_refs) {
249                 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
250                         "Perhaps you should specify a branch such as 'master'.\n");
251                 return 0;
252         }
253
254         /*
255          * NEEDSWORK: why does delete-refs have to be so specific to
256          * send-pack machinery that set_ref_status_for_push() cannot
257          * set this bit for us???
258          */
259         for (ref = remote_refs; ref; ref = ref->next)
260                 if (ref->deletion && !allow_deleting_refs)
261                         ref->status = REF_STATUS_REJECT_NODELETE;
262
263         if (!args->dry_run)
264                 advertise_shallow_grafts_buf(&req_buf);
265
266         /*
267          * Finally, tell the other end!
268          */
269         new_refs = 0;
270         for (ref = remote_refs; ref; ref = ref->next) {
271                 if (!ref_update_to_be_sent(ref, args))
272                         continue;
273
274                 if (!ref->deletion)
275                         new_refs++;
276
277                 if (args->dry_run) {
278                         ref->status = REF_STATUS_OK;
279                 } else {
280                         char *old_hex = sha1_to_hex(ref->old_sha1);
281                         char *new_hex = sha1_to_hex(ref->new_sha1);
282                         int quiet = quiet_supported && (args->quiet || !args->progress);
283
284                         if (!cmds_sent && (status_report || use_sideband ||
285                                            quiet || agent_supported)) {
286                                 packet_buf_write(&req_buf,
287                                                  "%s %s %s%c%s%s%s%s%s",
288                                                  old_hex, new_hex, ref->name, 0,
289                                                  status_report ? " report-status" : "",
290                                                  use_sideband ? " side-band-64k" : "",
291                                                  quiet ? " quiet" : "",
292                                                  agent_supported ? " agent=" : "",
293                                                  agent_supported ? git_user_agent_sanitized() : ""
294                                                 );
295                         }
296                         else
297                                 packet_buf_write(&req_buf, "%s %s %s",
298                                                  old_hex, new_hex, ref->name);
299                         ref->status = status_report ?
300                                 REF_STATUS_EXPECTING_REPORT :
301                                 REF_STATUS_OK;
302                         cmds_sent++;
303                 }
304         }
305
306         if (args->stateless_rpc) {
307                 if (!args->dry_run && (cmds_sent || is_repository_shallow())) {
308                         packet_buf_flush(&req_buf);
309                         send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);
310                 }
311         } else {
312                 write_or_die(out, req_buf.buf, req_buf.len);
313                 packet_flush(out);
314         }
315         strbuf_release(&req_buf);
316
317         if (use_sideband && cmds_sent) {
318                 memset(&demux, 0, sizeof(demux));
319                 demux.proc = sideband_demux;
320                 demux.data = fd;
321                 demux.out = -1;
322                 if (start_async(&demux))
323                         die("send-pack: unable to fork off sideband demultiplexer");
324                 in = demux.out;
325         }
326
327         if (new_refs && cmds_sent) {
328                 if (pack_objects(out, remote_refs, extra_have, args) < 0) {
329                         for (ref = remote_refs; ref; ref = ref->next)
330                                 ref->status = REF_STATUS_NONE;
331                         if (args->stateless_rpc)
332                                 close(out);
333                         if (git_connection_is_socket(conn))
334                                 shutdown(fd[0], SHUT_WR);
335                         if (use_sideband)
336                                 finish_async(&demux);
337                         fd[1] = -1;
338                         return -1;
339                 }
340                 if (!args->stateless_rpc)
341                         /* Closed by pack_objects() via start_command() */
342                         fd[1] = -1;
343         }
344         if (args->stateless_rpc && cmds_sent)
345                 packet_flush(out);
346
347         if (status_report && cmds_sent)
348                 ret = receive_status(in, remote_refs);
349         else
350                 ret = 0;
351         if (args->stateless_rpc)
352                 packet_flush(out);
353
354         if (use_sideband && cmds_sent) {
355                 if (finish_async(&demux)) {
356                         error("error in sideband demultiplexer");
357                         ret = -1;
358                 }
359                 close(demux.out);
360         }
361
362         if (ret < 0)
363                 return ret;
364
365         if (args->porcelain)
366                 return 0;
367
368         for (ref = remote_refs; ref; ref = ref->next) {
369                 switch (ref->status) {
370                 case REF_STATUS_NONE:
371                 case REF_STATUS_UPTODATE:
372                 case REF_STATUS_OK:
373                         break;
374                 default:
375                         return -1;
376                 }
377         }
378         return 0;
379 }