builtin-mailinfo.c: check error status from rewind and ftruncate
[git/spearce.git] / branch.c
blob05ef3f5c9ce6e1b55a7eb483a197fe9fd6e5437d
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;
29 tracking->spec.src = NULL;
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;
47 return 0;
50 void install_branch_config(int flag, const char *local, const char *origin, const char *remote)
52 struct strbuf key = STRBUF_INIT;
53 int rebasing = should_setup_rebase(origin);
55 strbuf_addf(&key, "branch.%s.remote", local);
56 git_config_set(key.buf, origin ? origin : ".");
58 strbuf_reset(&key);
59 strbuf_addf(&key, "branch.%s.merge", local);
60 git_config_set(key.buf, remote);
62 if (rebasing) {
63 strbuf_reset(&key);
64 strbuf_addf(&key, "branch.%s.rebase", local);
65 git_config_set(key.buf, "true");
68 if (flag & BRANCH_CONFIG_VERBOSE) {
69 strbuf_reset(&key);
71 strbuf_addstr(&key, origin ? "remote" : "local");
73 /* Are we tracking a proper "branch"? */
74 if (!prefixcmp(remote, "refs/heads/")) {
75 strbuf_addf(&key, " branch %s", remote + 11);
76 if (origin)
77 strbuf_addf(&key, " from %s", origin);
79 else
80 strbuf_addf(&key, " ref %s", remote);
81 printf("Branch %s set up to track %s%s.\n",
82 local, key.buf,
83 rebasing ? " by rebasing" : "");
85 strbuf_release(&key);
89 * This is called when new_ref is branched off of orig_ref, and tries
90 * to infer the settings for branch.<new_ref>.{remote,merge} from the
91 * config.
93 static int setup_tracking(const char *new_ref, const char *orig_ref,
94 enum branch_track track)
96 struct tracking tracking;
98 if (strlen(new_ref) > 1024 - 7 - 7 - 1)
99 return error("Tracking not set up: name too long: %s",
100 new_ref);
102 memset(&tracking, 0, sizeof(tracking));
103 tracking.spec.dst = (char *)orig_ref;
104 if (for_each_remote(find_tracked_branch, &tracking))
105 return 1;
107 if (!tracking.matches)
108 switch (track) {
109 case BRANCH_TRACK_ALWAYS:
110 case BRANCH_TRACK_EXPLICIT:
111 break;
112 default:
113 return 1;
116 if (tracking.matches > 1)
117 return error("Not tracking: ambiguous information for ref %s",
118 orig_ref);
120 install_branch_config(BRANCH_CONFIG_VERBOSE, new_ref, tracking.remote,
121 tracking.src ? tracking.src : orig_ref);
123 free(tracking.src);
124 return 0;
127 void create_branch(const char *head,
128 const char *name, const char *start_name,
129 int force, int reflog, enum branch_track track)
131 struct ref_lock *lock;
132 struct commit *commit;
133 unsigned char sha1[20];
134 char *real_ref, msg[PATH_MAX + 20];
135 struct strbuf ref = STRBUF_INIT;
136 int forcing = 0;
138 if (strbuf_check_branch_ref(&ref, name))
139 die("'%s' is not a valid branch name.", name);
141 if (resolve_ref(ref.buf, sha1, 1, NULL)) {
142 if (!force)
143 die("A branch named '%s' already exists.", name);
144 else if (!is_bare_repository() && !strcmp(head, name))
145 die("Cannot force update the current branch.");
146 forcing = 1;
149 real_ref = NULL;
150 if (get_sha1(start_name, sha1))
151 die("Not a valid object name: '%s'.", start_name);
153 switch (dwim_ref(start_name, strlen(start_name), sha1, &real_ref)) {
154 case 0:
155 /* Not branching from any existing branch */
156 if (track == BRANCH_TRACK_EXPLICIT)
157 die("Cannot setup tracking information; starting point is not a branch.");
158 break;
159 case 1:
160 /* Unique completion -- good, only if it is a real ref */
161 if (track == BRANCH_TRACK_EXPLICIT && !strcmp(real_ref, "HEAD"))
162 die("Cannot setup tracking information; starting point is not a branch.");
163 break;
164 default:
165 die("Ambiguous object name: '%s'.", start_name);
166 break;
169 if ((commit = lookup_commit_reference(sha1)) == NULL)
170 die("Not a valid branch point: '%s'.", start_name);
171 hashcpy(sha1, commit->object.sha1);
173 lock = lock_any_ref_for_update(ref.buf, NULL, 0);
174 if (!lock)
175 die_errno("Failed to lock ref for update");
177 if (reflog)
178 log_all_ref_updates = 1;
180 if (forcing)
181 snprintf(msg, sizeof msg, "branch: Reset from %s",
182 start_name);
183 else
184 snprintf(msg, sizeof msg, "branch: Created from %s",
185 start_name);
187 if (real_ref && track)
188 setup_tracking(name, real_ref, track);
190 if (write_ref_sha1(lock, sha1, msg) < 0)
191 die_errno("Failed to write ref");
193 strbuf_release(&ref);
194 free(real_ref);
197 void remove_branch_state(void)
199 unlink(git_path("MERGE_HEAD"));
200 unlink(git_path("MERGE_RR"));
201 unlink(git_path("MERGE_MSG"));
202 unlink(git_path("MERGE_MODE"));
203 unlink(git_path("SQUASH_MSG"));