config: Give error message when not changing a multivar
[git/dscho.git] / branch.c
blobc0c865a4b1b0fca038f32b77f2239d7987438ff5
1 #include "cache.h"
2 #include "branch.h"
3 #include "refs.h"
4 #include "remote.h"
5 #include "commit.h"
7 struct tracking {
8         struct refspec spec;
9         char *src;
10         const char *remote;
11         int matches;
14 static int find_tracked_branch(struct remote *remote, void *priv)
16         struct tracking *tracking = priv;
18         if (!remote_find_tracking(remote, &tracking->spec)) {
19                 if (++tracking->matches == 1) {
20                         tracking->src = tracking->spec.src;
21                         tracking->remote = remote->name;
22                 } else {
23                         free(tracking->spec.src);
24                         if (tracking->src) {
25                                 free(tracking->src);
26                                 tracking->src = NULL;
27                         }
28                 }
29                 tracking->spec.src = NULL;
30         }
32         return 0;
35 static int should_setup_rebase(const char *origin)
37         switch (autorebase) {
38         case AUTOREBASE_NEVER:
39                 return 0;
40         case AUTOREBASE_LOCAL:
41                 return origin == NULL;
42         case AUTOREBASE_REMOTE:
43                 return origin != NULL;
44         case AUTOREBASE_ALWAYS:
45                 return 1;
46         }
47         return 0;
50 void install_branch_config(int flag, const char *local, const char *origin, const char *remote)
52         const char *shortname = remote + 11;
53         int remote_is_branch = !prefixcmp(remote, "refs/heads/");
54         struct strbuf key = STRBUF_INIT;
55         int rebasing = should_setup_rebase(origin);
57         if (remote_is_branch
58             && !strcmp(local, shortname)
59             && !origin) {
60                 warning("Not setting branch %s as its own upstream.",
61                         local);
62                 return;
63         }
65         strbuf_addf(&key, "branch.%s.remote", local);
66         git_config_set(key.buf, origin ? origin : ".");
68         strbuf_reset(&key);
69         strbuf_addf(&key, "branch.%s.merge", local);
70         git_config_set(key.buf, remote);
72         if (rebasing) {
73                 strbuf_reset(&key);
74                 strbuf_addf(&key, "branch.%s.rebase", local);
75                 git_config_set(key.buf, "true");
76         }
78         if (flag & BRANCH_CONFIG_VERBOSE) {
79                 strbuf_reset(&key);
81                 strbuf_addstr(&key, origin ? "remote" : "local");
83                 /* Are we tracking a proper "branch"? */
84                 if (remote_is_branch) {
85                         strbuf_addf(&key, " branch %s", shortname);
86                         if (origin)
87                                 strbuf_addf(&key, " from %s", origin);
88                 }
89                 else
90                         strbuf_addf(&key, " ref %s", remote);
91                 printf("Branch %s set up to track %s%s.\n",
92                        local, key.buf,
93                        rebasing ? " by rebasing" : "");
94         }
95         strbuf_release(&key);
99  * This is called when new_ref is branched off of orig_ref, and tries
100  * to infer the settings for branch.<new_ref>.{remote,merge} from the
101  * config.
102  */
103 static int setup_tracking(const char *new_ref, const char *orig_ref,
104                           enum branch_track track)
106         struct tracking tracking;
108         if (strlen(new_ref) > 1024 - 7 - 7 - 1)
109                 return error("Tracking not set up: name too long: %s",
110                                 new_ref);
112         memset(&tracking, 0, sizeof(tracking));
113         tracking.spec.dst = (char *)orig_ref;
114         if (for_each_remote(find_tracked_branch, &tracking))
115                 return 1;
117         if (!tracking.matches)
118                 switch (track) {
119                 case BRANCH_TRACK_ALWAYS:
120                 case BRANCH_TRACK_EXPLICIT:
121                 case BRANCH_TRACK_OVERRIDE:
122                         break;
123                 default:
124                         return 1;
125                 }
127         if (tracking.matches > 1)
128                 return error("Not tracking: ambiguous information for ref %s",
129                                 orig_ref);
131         install_branch_config(BRANCH_CONFIG_VERBOSE, new_ref, tracking.remote,
132                               tracking.src ? tracking.src : orig_ref);
134         free(tracking.src);
135         return 0;
138 void create_branch(const char *head,
139                    const char *name, const char *start_name,
140                    int force, int reflog, enum branch_track track)
142         struct ref_lock *lock = NULL;
143         struct commit *commit;
144         unsigned char sha1[20];
145         char *real_ref, msg[PATH_MAX + 20];
146         struct strbuf ref = STRBUF_INIT;
147         int forcing = 0;
148         int dont_change_ref = 0;
149         int explicit_tracking = 0;
151         if (track == BRANCH_TRACK_EXPLICIT || track == BRANCH_TRACK_OVERRIDE)
152                 explicit_tracking = 1;
154         if (strbuf_check_branch_ref(&ref, name))
155                 die("'%s' is not a valid branch name.", name);
157         if (resolve_ref(ref.buf, sha1, 1, NULL)) {
158                 if (!force && track == BRANCH_TRACK_OVERRIDE)
159                         dont_change_ref = 1;
160                 else if (!force)
161                         die("A branch named '%s' already exists.", name);
162                 else if (!is_bare_repository() && head && !strcmp(head, name))
163                         die("Cannot force update the current branch.");
164                 forcing = 1;
165         }
167         real_ref = NULL;
168         if (get_sha1(start_name, sha1))
169                 die("Not a valid object name: '%s'.", start_name);
171         switch (dwim_ref(start_name, strlen(start_name), sha1, &real_ref)) {
172         case 0:
173                 /* Not branching from any existing branch */
174                 if (explicit_tracking)
175                         die("Cannot setup tracking information; starting point is not a branch.");
176                 break;
177         case 1:
178                 /* Unique completion -- good, only if it is a real branch */
179                 if (prefixcmp(real_ref, "refs/heads/") &&
180                     prefixcmp(real_ref, "refs/remotes/")) {
181                         if (explicit_tracking)
182                                 die("Cannot setup tracking information; starting point is not a branch.");
183                         else
184                                 real_ref = NULL;
185                 }
186                 break;
187         default:
188                 die("Ambiguous object name: '%s'.", start_name);
189                 break;
190         }
192         if ((commit = lookup_commit_reference(sha1)) == NULL)
193                 die("Not a valid branch point: '%s'.", start_name);
194         hashcpy(sha1, commit->object.sha1);
196         if (!dont_change_ref) {
197                 lock = lock_any_ref_for_update(ref.buf, NULL, 0);
198                 if (!lock)
199                         die_errno("Failed to lock ref for update");
200         }
202         if (reflog)
203                 log_all_ref_updates = 1;
205         if (forcing)
206                 snprintf(msg, sizeof msg, "branch: Reset to %s",
207                          start_name);
208         else if (!dont_change_ref)
209                 snprintf(msg, sizeof msg, "branch: Created from %s",
210                          start_name);
212         if (real_ref && track)
213                 setup_tracking(name, real_ref, track);
215         if (!dont_change_ref)
216                 if (write_ref_sha1(lock, sha1, msg) < 0)
217                         die_errno("Failed to write ref");
219         strbuf_release(&ref);
220         free(real_ref);
223 void remove_branch_state(void)
225         unlink(git_path("CHERRY_PICK_HEAD"));
226         unlink(git_path("MERGE_HEAD"));
227         unlink(git_path("MERGE_RR"));
228         unlink(git_path("MERGE_MSG"));
229         unlink(git_path("MERGE_MODE"));
230         unlink(git_path("SQUASH_MSG"));