aboutsummaryrefslogtreecommitdiff
path: root/branch.c
blob: 546c4b44060a3eddec3124379030bdb068d637d6 (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
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
#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");
	}
	strbuf_release(&key);

	if (flag & BRANCH_CONFIG_VERBOSE) {
		if (remote_is_branch && origin)
			printf_ln(rebasing ?
				  _("Branch %s set up to track remote branch %s from %s by rebasing.") :
				  _("Branch %s set up to track remote branch %s from %s."),
				  local, shortname, origin);
		else if (remote_is_branch && !origin)
			printf_ln(rebasing ?
				  _("Branch %s set up to track local branch %s by rebasing.") :
				  _("Branch %s set up to track local branch %s."),
				  local, shortname);
		else if (!remote_is_branch && origin)
			printf_ln(rebasing ?
				  _("Branch %s set up to track remote ref %s by rebasing.") :
				  _("Branch %s set up to track remote ref %s."),
				  local, remote);
		else if (!remote_is_branch && !origin)
			printf_ln(rebasing ?
				  _("Branch %s set up to track local ref %s by rebasing.") :
				  _("Branch %s set up to track local ref %s."),
				  local, remote);
		else
			die("BUG: impossible combination of %d and %p",
			    remote_is_branch, origin);
	}
}

/*
 * 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, int quiet)
{
	struct tracking tracking;
	int config_flags = quiet ? 0 : BRANCH_CONFIG_VERBOSE;

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

	free(tracking.src);
	return 0;
}

struct branch_desc_cb {
	const char *config_name;
	const char *value;
};

static int read_branch_desc_cb(const char *var, const char *value, void *cb)
{
	struct branch_desc_cb *desc = cb;
	if (strcmp(desc->config_name, var))
		return 0;
	free((char *)desc->value);
	return git_config_string(&desc->value, var, value);
}

int read_branch_desc(struct strbuf *buf, const char *branch_name)
{
	struct branch_desc_cb cb;
	struct strbuf name = STRBUF_INIT;
	strbuf_addf(&name, "branch.%s.description", branch_name);
	cb.config_name = name.buf;
	cb.value = NULL;
	if (git_config(read_branch_desc_cb, &cb) < 0) {
		strbuf_release(&name);
		return -1;
	}
	if (cb.value)
		strbuf_addstr(buf, cb.value);
	strbuf_release(&name);
	return 0;
}

int validate_new_branchname(const char *name, struct strbuf *ref,
			    int force, int attr_only)
{
	if (strbuf_check_branch_ref(ref, name))
		die(_("'%s' is not a valid branch name."), name);

	if (!ref_exists(ref->buf))
		return 0;
	else if (!force && !attr_only)
		die(_("A branch named '%s' already exists."), ref->buf + strlen("refs/heads/"));

	if (!attr_only) {
		const char *head;
		unsigned char sha1[20];

		head = resolve_ref_unsafe("HEAD", sha1, 0, NULL);
		if (!is_bare_repository() && head && !strcmp(head, ref->buf))
			die(_("Cannot force update the current branch."));
	}
	return 1;
}

static int check_tracking_branch(struct remote *remote, void *cb_data)
{
	char *tracking_branch = cb_data;
	struct refspec query;
	memset(&query, 0, sizeof(struct refspec));
	query.dst = tracking_branch;
	return !(remote_find_tracking(remote, &query) ||
		 prefixcmp(query.src, "refs/heads/"));
}

static int validate_remote_tracking_branch(char *ref)
{
	return !for_each_remote(check_tracking_branch, ref);
}

static const char upstream_not_branch[] =
N_("Cannot setup tracking information; starting point '%s' is not a branch.");
static const char upstream_missing[] =
N_("the requested upstream branch '%s' does not exist");
static const char upstream_advice[] =
N_("\n"
"If you are planning on basing your work on an upstream\n"
"branch that already exists at the remote, you may need to\n"
"run \"git fetch\" to retrieve it.\n"
"\n"
"If you are planning to push out a new local branch that\n"
"will track its remote counterpart, you may want to use\n"
"\"git push -u\" to set the upstream config as you push.");

void create_branch(const char *head,
		   const char *name, const char *start_name,
		   int force, int reflog, int clobber_head,
		   int quiet, 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 (validate_new_branchname(name, &ref, force,
				    track == BRANCH_TRACK_OVERRIDE ||
				    clobber_head)) {
		if (!force)
			dont_change_ref = 1;
		else
			forcing = 1;
	}

	real_ref = NULL;
	if (get_sha1(start_name, sha1)) {
		if (explicit_tracking) {
			if (advice_set_upstream_failure) {
				error(_(upstream_missing), start_name);
				advise(_(upstream_advice));
				exit(1);
			}
			die(_(upstream_missing), start_name);
		}
		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(_(upstream_not_branch), start_name);
		break;
	case 1:
		/* Unique completion -- good, only if it is a real branch */
		if (prefixcmp(real_ref, "refs/heads/") &&
		    validate_remote_tracking_branch(real_ref)) {
			if (explicit_tracking)
				die(_(upstream_not_branch), start_name);
			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(ref.buf + 11, real_ref, track, quiet);

	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("CHERRY_PICK_HEAD"));
	unlink(git_path("REVERT_HEAD"));
	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"));
}