Merge branch 'aw/rebase-i-stop-on-failure-to-amend' into maint
[git] / branch.c
1 #include "cache.h"
2 #include "branch.h"
3 #include "refs.h"
4 #include "remote.h"
5 #include "commit.h"
6 #include "sequencer.h"
7
8 struct tracking {
9         struct refspec spec;
10         char *src;
11         const char *remote;
12         int matches;
13 };
14
15 static int find_tracked_branch(struct remote *remote, void *priv)
16 {
17         struct tracking *tracking = priv;
18
19         if (!remote_find_tracking(remote, &tracking->spec)) {
20                 if (++tracking->matches == 1) {
21                         tracking->src = tracking->spec.src;
22                         tracking->remote = remote->name;
23                 } else {
24                         free(tracking->spec.src);
25                         if (tracking->src) {
26                                 free(tracking->src);
27                                 tracking->src = NULL;
28                         }
29                 }
30                 tracking->spec.src = NULL;
31         }
32
33         return 0;
34 }
35
36 static int should_setup_rebase(const char *origin)
37 {
38         switch (autorebase) {
39         case AUTOREBASE_NEVER:
40                 return 0;
41         case AUTOREBASE_LOCAL:
42                 return origin == NULL;
43         case AUTOREBASE_REMOTE:
44                 return origin != NULL;
45         case AUTOREBASE_ALWAYS:
46                 return 1;
47         }
48         return 0;
49 }
50
51 void install_branch_config(int flag, const char *local, const char *origin, const char *remote)
52 {
53         const char *shortname = remote + 11;
54         int remote_is_branch = !prefixcmp(remote, "refs/heads/");
55         struct strbuf key = STRBUF_INIT;
56         int rebasing = should_setup_rebase(origin);
57
58         if (remote_is_branch
59             && !strcmp(local, shortname)
60             && !origin) {
61                 warning("Not setting branch %s as its own upstream.",
62                         local);
63                 return;
64         }
65
66         strbuf_addf(&key, "branch.%s.remote", local);
67         git_config_set(key.buf, origin ? origin : ".");
68
69         strbuf_reset(&key);
70         strbuf_addf(&key, "branch.%s.merge", local);
71         git_config_set(key.buf, remote);
72
73         if (rebasing) {
74                 strbuf_reset(&key);
75                 strbuf_addf(&key, "branch.%s.rebase", local);
76                 git_config_set(key.buf, "true");
77         }
78
79         if (flag & BRANCH_CONFIG_VERBOSE) {
80                 strbuf_reset(&key);
81
82                 strbuf_addstr(&key, origin ? "remote" : "local");
83
84                 /* Are we tracking a proper "branch"? */
85                 if (remote_is_branch) {
86                         strbuf_addf(&key, " branch %s", shortname);
87                         if (origin)
88                                 strbuf_addf(&key, " from %s", origin);
89                 }
90                 else
91                         strbuf_addf(&key, " ref %s", remote);
92                 printf("Branch %s set up to track %s%s.\n",
93                        local, key.buf,
94                        rebasing ? " by rebasing" : "");
95         }
96         strbuf_release(&key);
97 }
98
99 /*
100  * This is called when new_ref is branched off of orig_ref, and tries
101  * to infer the settings for branch.<new_ref>.{remote,merge} from the
102  * config.
103  */
104 static int setup_tracking(const char *new_ref, const char *orig_ref,
105                           enum branch_track track)
106 {
107         struct tracking tracking;
108
109         if (strlen(new_ref) > 1024 - 7 - 7 - 1)
110                 return error("Tracking not set up: name too long: %s",
111                                 new_ref);
112
113         memset(&tracking, 0, sizeof(tracking));
114         tracking.spec.dst = (char *)orig_ref;
115         if (for_each_remote(find_tracked_branch, &tracking))
116                 return 1;
117
118         if (!tracking.matches)
119                 switch (track) {
120                 case BRANCH_TRACK_ALWAYS:
121                 case BRANCH_TRACK_EXPLICIT:
122                 case BRANCH_TRACK_OVERRIDE:
123                         break;
124                 default:
125                         return 1;
126                 }
127
128         if (tracking.matches > 1)
129                 return error("Not tracking: ambiguous information for ref %s",
130                                 orig_ref);
131
132         install_branch_config(BRANCH_CONFIG_VERBOSE, new_ref, tracking.remote,
133                               tracking.src ? tracking.src : orig_ref);
134
135         free(tracking.src);
136         return 0;
137 }
138
139 int validate_new_branchname(const char *name, struct strbuf *ref,
140                             int force, int attr_only)
141 {
142         if (strbuf_check_branch_ref(ref, name))
143                 die("'%s' is not a valid branch name.", name);
144
145         if (!ref_exists(ref->buf))
146                 return 0;
147         else if (!force && !attr_only)
148                 die("A branch named '%s' already exists.", ref->buf + strlen("refs/heads/"));
149
150         if (!attr_only) {
151                 const char *head;
152                 unsigned char sha1[20];
153
154                 head = resolve_ref("HEAD", sha1, 0, NULL);
155                 if (!is_bare_repository() && head && !strcmp(head, ref->buf))
156                         die("Cannot force update the current branch.");
157         }
158         return 1;
159 }
160
161 void create_branch(const char *head,
162                    const char *name, const char *start_name,
163                    int force, int reflog, int clobber_head,
164                    enum branch_track track)
165 {
166         struct ref_lock *lock = NULL;
167         struct commit *commit;
168         unsigned char sha1[20];
169         char *real_ref, msg[PATH_MAX + 20];
170         struct strbuf ref = STRBUF_INIT;
171         int forcing = 0;
172         int dont_change_ref = 0;
173         int explicit_tracking = 0;
174
175         if (track == BRANCH_TRACK_EXPLICIT || track == BRANCH_TRACK_OVERRIDE)
176                 explicit_tracking = 1;
177
178         if (validate_new_branchname(name, &ref, force,
179                                     track == BRANCH_TRACK_OVERRIDE ||
180                                     clobber_head)) {
181                 if (!force)
182                         dont_change_ref = 1;
183                 else
184                         forcing = 1;
185         }
186
187         real_ref = NULL;
188         if (get_sha1(start_name, sha1))
189                 die("Not a valid object name: '%s'.", start_name);
190
191         switch (dwim_ref(start_name, strlen(start_name), sha1, &real_ref)) {
192         case 0:
193                 /* Not branching from any existing branch */
194                 if (explicit_tracking)
195                         die("Cannot setup tracking information; starting point is not a branch.");
196                 break;
197         case 1:
198                 /* Unique completion -- good, only if it is a real branch */
199                 if (prefixcmp(real_ref, "refs/heads/") &&
200                     prefixcmp(real_ref, "refs/remotes/")) {
201                         if (explicit_tracking)
202                                 die("Cannot setup tracking information; starting point is not a branch.");
203                         else
204                                 real_ref = NULL;
205                 }
206                 break;
207         default:
208                 die("Ambiguous object name: '%s'.", start_name);
209                 break;
210         }
211
212         if ((commit = lookup_commit_reference(sha1)) == NULL)
213                 die("Not a valid branch point: '%s'.", start_name);
214         hashcpy(sha1, commit->object.sha1);
215
216         if (!dont_change_ref) {
217                 lock = lock_any_ref_for_update(ref.buf, NULL, 0);
218                 if (!lock)
219                         die_errno("Failed to lock ref for update");
220         }
221
222         if (reflog)
223                 log_all_ref_updates = 1;
224
225         if (forcing)
226                 snprintf(msg, sizeof msg, "branch: Reset to %s",
227                          start_name);
228         else if (!dont_change_ref)
229                 snprintf(msg, sizeof msg, "branch: Created from %s",
230                          start_name);
231
232         if (real_ref && track)
233                 setup_tracking(ref.buf+11, real_ref, track);
234
235         if (!dont_change_ref)
236                 if (write_ref_sha1(lock, sha1, msg) < 0)
237                         die_errno("Failed to write ref");
238
239         strbuf_release(&ref);
240         free(real_ref);
241 }
242
243 void remove_branch_state(void)
244 {
245         unlink(git_path("CHERRY_PICK_HEAD"));
246         unlink(git_path("REVERT_HEAD"));
247         unlink(git_path("MERGE_HEAD"));
248         unlink(git_path("MERGE_RR"));
249         unlink(git_path("MERGE_MSG"));
250         unlink(git_path("MERGE_MODE"));
251         unlink(git_path("SQUASH_MSG"));
252         remove_sequencer_state(0);
253 }