index-pack: be careful after fixing up the header/footer
[git/dscho.git] / builtin-read-tree.c
blob72a6de302f88728af17ce5c5c6983c5267afc6f6
1 /*
2 * GIT - The information manager from hell
4 * Copyright (C) Linus Torvalds, 2005
5 */
7 #include "cache.h"
8 #include "object.h"
9 #include "tree.h"
10 #include "tree-walk.h"
11 #include "cache-tree.h"
12 #include "unpack-trees.h"
13 #include "dir.h"
14 #include "builtin.h"
16 static int nr_trees;
17 static struct tree *trees[MAX_UNPACK_TREES];
19 static int list_tree(unsigned char *sha1)
21 struct tree *tree;
23 if (nr_trees >= MAX_UNPACK_TREES)
24 die("I cannot read more than %d trees", MAX_UNPACK_TREES);
25 tree = parse_tree_indirect(sha1);
26 if (!tree)
27 return -1;
28 trees[nr_trees++] = tree;
29 return 0;
32 static void prime_cache_tree_rec(struct cache_tree *it, struct tree *tree)
34 struct tree_desc desc;
35 struct name_entry entry;
36 int cnt;
38 hashcpy(it->sha1, tree->object.sha1);
39 init_tree_desc(&desc, tree->buffer, tree->size);
40 cnt = 0;
41 while (tree_entry(&desc, &entry)) {
42 if (!S_ISDIR(entry.mode))
43 cnt++;
44 else {
45 struct cache_tree_sub *sub;
46 struct tree *subtree = lookup_tree(entry.sha1);
47 if (!subtree->object.parsed)
48 parse_tree(subtree);
49 sub = cache_tree_sub(it, entry.path);
50 sub->cache_tree = cache_tree();
51 prime_cache_tree_rec(sub->cache_tree, subtree);
52 cnt += sub->cache_tree->entry_count;
55 it->entry_count = cnt;
58 static void prime_cache_tree(void)
60 if (!nr_trees)
61 return;
62 active_cache_tree = cache_tree();
63 prime_cache_tree_rec(active_cache_tree, trees[0]);
67 static const char read_tree_usage[] = "git-read-tree (<sha> | [[-m [--trivial] [--aggressive] | --reset | --prefix=<prefix>] [-u | -i]] [--exclude-per-directory=<gitignore>] [--index-output=<file>] <sha1> [<sha2> [<sha3>]])";
69 static struct lock_file lock_file;
71 int cmd_read_tree(int argc, const char **argv, const char *unused_prefix)
73 int i, newfd, stage = 0;
74 unsigned char sha1[20];
75 struct tree_desc t[MAX_UNPACK_TREES];
76 struct unpack_trees_options opts;
78 memset(&opts, 0, sizeof(opts));
79 opts.head_idx = -1;
80 opts.src_index = &the_index;
81 opts.dst_index = &the_index;
83 git_config(git_default_config, NULL);
85 newfd = hold_locked_index(&lock_file, 1);
87 for (i = 1; i < argc; i++) {
88 const char *arg = argv[i];
90 /* "-u" means "update", meaning that a merge will update
91 * the working tree.
93 if (!strcmp(arg, "-u")) {
94 opts.update = 1;
95 continue;
98 if (!strcmp(arg, "-v")) {
99 opts.verbose_update = 1;
100 continue;
103 /* "-i" means "index only", meaning that a merge will
104 * not even look at the working tree.
106 if (!strcmp(arg, "-i")) {
107 opts.index_only = 1;
108 continue;
111 if (!prefixcmp(arg, "--index-output=")) {
112 set_alternate_index_output(arg + 15);
113 continue;
116 /* "--prefix=<subdirectory>/" means keep the current index
117 * entries and put the entries from the tree under the
118 * given subdirectory.
120 if (!prefixcmp(arg, "--prefix=")) {
121 if (stage || opts.merge || opts.prefix)
122 usage(read_tree_usage);
123 opts.prefix = arg + 9;
124 opts.merge = 1;
125 stage = 1;
126 if (read_cache_unmerged())
127 die("you need to resolve your current index first");
128 continue;
131 /* This differs from "-m" in that we'll silently ignore
132 * unmerged entries and overwrite working tree files that
133 * correspond to them.
135 if (!strcmp(arg, "--reset")) {
136 if (stage || opts.merge || opts.prefix)
137 usage(read_tree_usage);
138 opts.reset = 1;
139 opts.merge = 1;
140 stage = 1;
141 read_cache_unmerged();
142 continue;
145 if (!strcmp(arg, "--trivial")) {
146 opts.trivial_merges_only = 1;
147 continue;
150 if (!strcmp(arg, "--aggressive")) {
151 opts.aggressive = 1;
152 continue;
155 /* "-m" stands for "merge", meaning we start in stage 1 */
156 if (!strcmp(arg, "-m")) {
157 if (stage || opts.merge || opts.prefix)
158 usage(read_tree_usage);
159 if (read_cache_unmerged())
160 die("you need to resolve your current index first");
161 stage = 1;
162 opts.merge = 1;
163 continue;
166 if (!prefixcmp(arg, "--exclude-per-directory=")) {
167 struct dir_struct *dir;
169 if (opts.dir)
170 die("more than one --exclude-per-directory are given.");
172 dir = xcalloc(1, sizeof(*opts.dir));
173 dir->show_ignored = 1;
174 dir->exclude_per_dir = arg + 24;
175 opts.dir = dir;
176 /* We do not need to nor want to do read-directory
177 * here; we are merely interested in reusing the
178 * per directory ignore stack mechanism.
180 continue;
183 /* using -u and -i at the same time makes no sense */
184 if (1 < opts.index_only + opts.update)
185 usage(read_tree_usage);
187 if (get_sha1(arg, sha1))
188 die("Not a valid object name %s", arg);
189 if (list_tree(sha1) < 0)
190 die("failed to unpack tree object %s", arg);
191 stage++;
193 if ((opts.update||opts.index_only) && !opts.merge)
194 usage(read_tree_usage);
195 if ((opts.dir && !opts.update))
196 die("--exclude-per-directory is meaningless unless -u");
198 if (opts.merge) {
199 if (stage < 2)
200 die("just how do you expect me to merge %d trees?", stage-1);
201 switch (stage - 1) {
202 case 1:
203 opts.fn = opts.prefix ? bind_merge : oneway_merge;
204 break;
205 case 2:
206 opts.fn = twoway_merge;
207 break;
208 case 3:
209 default:
210 opts.fn = threeway_merge;
211 cache_tree_free(&active_cache_tree);
212 break;
215 if (stage - 1 >= 3)
216 opts.head_idx = stage - 2;
217 else
218 opts.head_idx = 1;
221 for (i = 0; i < nr_trees; i++) {
222 struct tree *tree = trees[i];
223 parse_tree(tree);
224 init_tree_desc(t+i, tree->buffer, tree->size);
226 if (unpack_trees(nr_trees, t, &opts))
227 return 128;
230 * When reading only one tree (either the most basic form,
231 * "-m ent" or "--reset ent" form), we can obtain a fully
232 * valid cache-tree because the index must match exactly
233 * what came from the tree.
235 if (nr_trees && !opts.prefix && (!opts.merge || (stage == 2))) {
236 cache_tree_free(&active_cache_tree);
237 prime_cache_tree();
240 if (write_cache(newfd, active_cache, active_nr) ||
241 commit_locked_index(&lock_file))
242 die("unable to write new index file");
243 return 0;