summaryrefslogtreecommitdiff
path: root/builtin-read-tree.c
blob: 8ba436dbace7ec25ec5768a5c6c84f3202f92159 (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
/*
 * GIT - The information manager from hell
 *
 * Copyright (C) Linus Torvalds, 2005
 */

#include "cache.h"
#include "object.h"
#include "tree.h"
#include "tree-walk.h"
#include "cache-tree.h"
#include "unpack-trees.h"
#include "dir.h"
#include "builtin.h"

static struct object_list *trees;

static int list_tree(unsigned char *sha1)
{
	struct tree *tree = parse_tree_indirect(sha1);
	if (!tree)
		return -1;
	object_list_append(&tree->object, &trees);
	return 0;
}

static int read_cache_unmerged(void)
{
	int i;
	struct cache_entry **dst;
	struct cache_entry *last = NULL;

	read_cache();
	dst = active_cache;
	for (i = 0; i < active_nr; i++) {
		struct cache_entry *ce = active_cache[i];
		if (ce_stage(ce)) {
			if (last && !strcmp(ce->name, last->name))
				continue;
			cache_tree_invalidate_path(active_cache_tree, ce->name);
			last = ce;
			ce->ce_mode = 0;
			ce->ce_flags &= ~htons(CE_STAGEMASK);
		}
		*dst++ = ce;
	}
	active_nr = dst - active_cache;
	return !!last;
}

static void prime_cache_tree_rec(struct cache_tree *it, struct tree *tree)
{
	struct tree_desc desc;
	struct name_entry entry;
	int cnt;

	hashcpy(it->sha1, tree->object.sha1);
	desc.buf = tree->buffer;
	desc.size = tree->size;
	cnt = 0;
	while (tree_entry(&desc, &entry)) {
		if (!S_ISDIR(entry.mode))
			cnt++;
		else {
			struct cache_tree_sub *sub;
			struct tree *subtree = lookup_tree(entry.sha1);
			if (!subtree->object.parsed)
				parse_tree(subtree);
			sub = cache_tree_sub(it, entry.path);
			sub->cache_tree = cache_tree();
			prime_cache_tree_rec(sub->cache_tree, subtree);
			cnt += sub->cache_tree->entry_count;
		}
	}
	it->entry_count = cnt;
}

static void prime_cache_tree(void)
{
	struct tree *tree = (struct tree *)trees->item;
	if (!tree)
		return;
	active_cache_tree = cache_tree();
	prime_cache_tree_rec(active_cache_tree, tree);

}

static const char read_tree_usage[] = "git-read-tree (<sha> | [[-m [--aggressive] | --reset | --prefix=<prefix>] [-u | -i]] [--exclude-per-directory=<gitignore>] <sha1> [<sha2> [<sha3>]])";

static struct lock_file lock_file;

int cmd_read_tree(int argc, const char **argv, const char *unused_prefix)
{
	int i, newfd, stage = 0;
	unsigned char sha1[20];
	struct unpack_trees_options opts;

	memset(&opts, 0, sizeof(opts));
	opts.head_idx = -1;

	setup_git_directory();
	git_config(git_default_config);

	newfd = hold_lock_file_for_update(&lock_file, get_index_file(), 1);

	git_config(git_default_config);

	for (i = 1; i < argc; i++) {
		const char *arg = argv[i];

		/* "-u" means "update", meaning that a merge will update
		 * the working tree.
		 */
		if (!strcmp(arg, "-u")) {
			opts.update = 1;
			continue;
		}

		if (!strcmp(arg, "-v")) {
			opts.verbose_update = 1;
			continue;
		}

		/* "-i" means "index only", meaning that a merge will
		 * not even look at the working tree.
		 */
		if (!strcmp(arg, "-i")) {
			opts.index_only = 1;
			continue;
		}

		/* "--prefix=<subdirectory>/" means keep the current index
		 *  entries and put the entries from the tree under the
		 * given subdirectory.
		 */
		if (!strncmp(arg, "--prefix=", 9)) {
			if (stage || opts.merge || opts.prefix)
				usage(read_tree_usage);
			opts.prefix = arg + 9;
			opts.merge = 1;
			stage = 1;
			if (read_cache_unmerged())
				die("you need to resolve your current index first");
			continue;
		}

		/* This differs from "-m" in that we'll silently ignore
		 * unmerged entries and overwrite working tree files that
		 * correspond to them.
		 */
		if (!strcmp(arg, "--reset")) {
			if (stage || opts.merge || opts.prefix)
				usage(read_tree_usage);
			opts.reset = 1;
			opts.merge = 1;
			stage = 1;
			read_cache_unmerged();
			continue;
		}

		if (!strcmp(arg, "--trivial")) {
			opts.trivial_merges_only = 1;
			continue;
		}

		if (!strcmp(arg, "--aggressive")) {
			opts.aggressive = 1;
			continue;
		}

		/* "-m" stands for "merge", meaning we start in stage 1 */
		if (!strcmp(arg, "-m")) {
			if (stage || opts.merge || opts.prefix)
				usage(read_tree_usage);
			if (read_cache_unmerged())
				die("you need to resolve your current index first");
			stage = 1;
			opts.merge = 1;
			continue;
		}

		if (!strncmp(arg, "--exclude-per-directory=", 24)) {
			struct dir_struct *dir;

			if (opts.dir)
				die("more than one --exclude-per-directory are given.");

			dir = calloc(1, sizeof(*opts.dir));
			dir->show_ignored = 1;
			dir->exclude_per_dir = arg + 24;
			opts.dir = dir;
			/* We do not need to nor want to do read-directory
			 * here; we are merely interested in reusing the
			 * per directory ignore stack mechanism.
			 */
			continue;
		}

		/* using -u and -i at the same time makes no sense */
		if (1 < opts.index_only + opts.update)
			usage(read_tree_usage);

		if (get_sha1(arg, sha1))
			die("Not a valid object name %s", arg);
		if (list_tree(sha1) < 0)
			die("failed to unpack tree object %s", arg);
		stage++;
	}
	if ((opts.update||opts.index_only) && !opts.merge)
		usage(read_tree_usage);
	if ((opts.dir && !opts.update))
		die("--exclude-per-directory is meaningless unless -u");

	if (opts.prefix) {
		int pfxlen = strlen(opts.prefix);
		int pos;
		if (opts.prefix[pfxlen-1] != '/')
			die("prefix must end with /");
		if (stage != 2)
			die("binding merge takes only one tree");
		pos = cache_name_pos(opts.prefix, pfxlen);
		if (0 <= pos)
			die("corrupt index file");
		pos = -pos-1;
		if (pos < active_nr &&
		    !strncmp(active_cache[pos]->name, opts.prefix, pfxlen))
			die("subdirectory '%s' already exists.", opts.prefix);
		pos = cache_name_pos(opts.prefix, pfxlen-1);
		if (0 <= pos)
			die("file '%.*s' already exists.",
					pfxlen-1, opts.prefix);
	}

	if (opts.merge) {
		if (stage < 2)
			die("just how do you expect me to merge %d trees?", stage-1);
		switch (stage - 1) {
		case 1:
			opts.fn = opts.prefix ? bind_merge : oneway_merge;
			break;
		case 2:
			opts.fn = twoway_merge;
			break;
		case 3:
		default:
			opts.fn = threeway_merge;
			cache_tree_free(&active_cache_tree);
			break;
		}

		if (stage - 1 >= 3)
			opts.head_idx = stage - 2;
		else
			opts.head_idx = 1;
	}

	unpack_trees(trees, &opts);

	/*
	 * When reading only one tree (either the most basic form,
	 * "-m ent" or "--reset ent" form), we can obtain a fully
	 * valid cache-tree because the index must match exactly
	 * what came from the tree.
	 */
	if (trees && trees->item && !opts.prefix && (!opts.merge || (stage == 2))) {
		cache_tree_free(&active_cache_tree);
		prime_cache_tree();
	}

	if (write_cache(newfd, active_cache, active_nr) ||
	    close(newfd) || commit_lock_file(&lock_file))
		die("unable to write new index file");
	return 0;
}