aboutsummaryrefslogtreecommitdiff
path: root/branch.c
blob: da5c03e56545b79cb92dd850ed09e81c21f9162f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
#include "cache.h"
#include "branch.h"
#include "refs.h"
#include "remote.h"
#include "commit.h"

struct tracking {
	struct refspec spec;
	char *src;
	const char *remote;
	int matches;
};

static int find_tracked_branch(struct remote *remote, void *priv)
{
	struct tracking *tracking = priv;

	if (!remote_find_tracking(remote, &tracking->spec)) {
		if (++tracking->matches == 1) {
			tracking->src = tracking->spec.src;
			tracking->remote = remote->name;
		} else {
			free(tracking->spec.src);
			if (tracking->src) {
				free(tracking->src);
				tracking->src = NULL;
			}
		}
		tracking->spec.src = NULL;
	}

	return 0;
}

static int should_setup_rebase(const char *origin)
{
	switch (autorebase) {
	case AUTOREBASE_NEVER:
		return 0;
	case AUTOREBASE_LOCAL:
		return origin == NULL;
	case AUTOREBASE_REMOTE:
		return origin != NULL;
	case AUTOREBASE_ALWAYS:
		return 1;
	}
	return 0;
}

void install_branch_config(int flag, const char *local, const char *origin, const char *remote)
{
	const char *shortname = remote + 11;
	int remote_is_branch = !prefixcmp(remote, "refs/heads/");
	struct strbuf key = STRBUF_INIT;
	int rebasing = should_setup_rebase(origin);

	if (remote_is_branch
	    && !strcmp(local, shortname)
	    && !origin) {
		warning("Not setting branch %s as its own upstream.",
			local);
		return;
	}

	strbuf_addf(&key, "branch.%s.remote", local);
	git_config_set(key.buf, origin ? origin : ".");

	strbuf_reset(&key);
	strbuf_addf(&key, "branch.%s.merge", local);
	git_config_set(key.buf, remote);

	if (rebasing) {
		strbuf_reset(&key);
		strbuf_addf(&key, "branch.%s.rebase", local);
		git_config_set(key.buf, "true");
	}

	if (flag & BRANCH_CONFIG_VERBOSE) {
		strbuf_reset(&key);

		strbuf_addstr(&key, origin ? "remote" : "local");

		/* Are we tracking a proper "branch"? */
		if (remote_is_branch) {
			strbuf_addf(&key, " branch %s", shortname);
			if (origin)
				strbuf_addf(&key, " from %s", origin);
		}
		else
			strbuf_addf(&key, " ref %s", remote);
		printf("Branch %s set up to track %s%s.\n",
		       local, key.buf,
		       rebasing ? " by rebasing" : "");
	}
	strbuf_release(&key);
}

/*
 * This is called when new_ref is branched off of orig_ref, and tries
 * to infer the settings for branch.<new_ref>.{remote,merge} from the
 * config.
 */
static int setup_tracking(const char *new_ref, const char *orig_ref,
                          enum branch_track track)
{
	struct tracking tracking;

	if (strlen(new_ref) > 1024 - 7 - 7 - 1)
		return error("Tracking not set up: name too long: %s",
				new_ref);

	memset(&tracking, 0, sizeof(tracking));
	tracking.spec.dst = (char *)orig_ref;
	if (for_each_remote(find_tracked_branch, &tracking))
		return 1;

	if (!tracking.matches)
		switch (track) {
		case BRANCH_TRACK_ALWAYS:
		case BRANCH_TRACK_EXPLICIT:
		case BRANCH_TRACK_OVERRIDE:
			break;
		default:
			return 1;
		}

	if (tracking.matches > 1)
		return error("Not tracking: ambiguous information for ref %s",
				orig_ref);

	install_branch_config(BRANCH_CONFIG_VERBOSE, new_ref, tracking.remote,
			      tracking.src ? tracking.src : orig_ref);

	free(tracking.src);
	return 0;
}

void create_branch(const char *head,
		   const char *name, const char *start_name,
		   int force, int reflog, enum branch_track track)
{
	struct ref_lock *lock = NULL;
	struct commit *commit;
	unsigned char sha1[20];
	char *real_ref, msg[PATH_MAX + 20];
	struct strbuf ref = STRBUF_INIT;
	int forcing = 0;
	int dont_change_ref = 0;
	int explicit_tracking = 0;

	if (track == BRANCH_TRACK_EXPLICIT || track == BRANCH_TRACK_OVERRIDE)
		explicit_tracking = 1;

	if (strbuf_check_branch_ref(&ref, name))
		die("'%s' is not a valid branch name.", name);

	if (resolve_ref(ref.buf, sha1, 1, NULL)) {
		if (!force && track == BRANCH_TRACK_OVERRIDE)
			dont_change_ref = 1;
		else if (!force)
			die("A branch named '%s' already exists.", name);
		else if (!is_bare_repository() && head && !strcmp(head, name))
			die("Cannot force update the current branch.");
		forcing = 1;
	}

	real_ref = NULL;
	if (get_sha1(start_name, sha1))
		die("Not a valid object name: '%s'.", start_name);

	switch (dwim_ref(start_name, strlen(start_name), sha1, &real_ref)) {
	case 0:
		/* Not branching from any existing branch */
		if (explicit_tracking)
			die("Cannot setup tracking information; starting point is not a branch.");
		break;
	case 1:
		/* Unique completion -- good, only if it is a real branch */
		if (prefixcmp(real_ref, "refs/heads/") &&
		    prefixcmp(real_ref, "refs/remotes/")) {
			if (explicit_tracking)
				die("Cannot setup tracking information; starting point is not a branch.");
			else
				real_ref = NULL;
		}
		break;
	default:
		die("Ambiguous object name: '%s'.", start_name);
		break;
	}

	if ((commit = lookup_commit_reference(sha1)) == NULL)
		die("Not a valid branch point: '%s'.", start_name);
	hashcpy(sha1, commit->object.sha1);

	if (!dont_change_ref) {
		lock = lock_any_ref_for_update(ref.buf, NULL, 0);
		if (!lock)
			die_errno("Failed to lock ref for update");
	}

	if (reflog)
		log_all_ref_updates = 1;

	if (forcing)
		snprintf(msg, sizeof msg, "branch: Reset to %s",
			 start_name);
	else if (!dont_change_ref)
		snprintf(msg, sizeof msg, "branch: Created from %s",
			 start_name);

	if (real_ref && track)
		setup_tracking(name, real_ref, track);

	if (!dont_change_ref)
		if (write_ref_sha1(lock, sha1, msg) < 0)
			die_errno("Failed to write ref");

	strbuf_release(&ref);
	free(real_ref);
}

void remove_branch_state(void)
{
	unlink(git_path("MERGE_HEAD"));
	unlink(git_path("MERGE_RR"));
	unlink(git_path("MERGE_MSG"));
	unlink(git_path("MERGE_MODE"));
	unlink(git_path("SQUASH_MSG"));
}