Do a cross-project merge of Paul Mackerras' gitk visualizer
[git/git.git] / write-tree.c
1 /*
2 * GIT - The information manager from hell
3 *
4 * Copyright (C) Linus Torvalds, 2005
5 */
6 #include "cache.h"
7
8 static int check_valid_sha1(unsigned char *sha1)
9 {
10 char *filename = sha1_file_name(sha1);
11 int ret;
12
13 /* If we were anal, we'd check that the sha1 of the contents actually matches */
14 ret = access(filename, R_OK);
15 if (ret)
16 perror(filename);
17 return ret;
18 }
19
20 static int write_tree(struct cache_entry **cachep, int maxentries, const char *base, int baselen, unsigned char *returnsha1)
21 {
22 unsigned char subdir_sha1[20];
23 unsigned long size, offset;
24 char *buffer;
25 int nr;
26
27 /* Guess at some random initial size */
28 size = 8192;
29 buffer = xmalloc(size);
30 offset = 0;
31
32 nr = 0;
33 while (nr < maxentries) {
34 struct cache_entry *ce = cachep[nr];
35 const char *pathname = ce->name, *filename, *dirname;
36 int pathlen = ce_namelen(ce), entrylen;
37 unsigned char *sha1;
38 unsigned int mode;
39
40 /* Did we hit the end of the directory? Return how many we wrote */
41 if (baselen >= pathlen || memcmp(base, pathname, baselen))
42 break;
43
44 sha1 = ce->sha1;
45 mode = ntohl(ce->ce_mode);
46
47 /* Do we have _further_ subdirectories? */
48 filename = pathname + baselen;
49 dirname = strchr(filename, '/');
50 if (dirname) {
51 int subdir_written;
52
53 subdir_written = write_tree(cachep + nr, maxentries - nr, pathname, dirname-pathname+1, subdir_sha1);
54 nr += subdir_written;
55
56 /* Now we need to write out the directory entry into this tree.. */
57 mode = S_IFDIR;
58 pathlen = dirname - pathname;
59
60 /* ..but the directory entry doesn't count towards the total count */
61 nr--;
62 sha1 = subdir_sha1;
63 }
64
65 if (check_valid_sha1(sha1) < 0)
66 exit(1);
67
68 entrylen = pathlen - baselen;
69 if (offset + entrylen + 100 > size) {
70 size = alloc_nr(offset + entrylen + 100);
71 buffer = xrealloc(buffer, size);
72 }
73 offset += sprintf(buffer + offset, "%o %.*s", mode, entrylen, filename);
74 buffer[offset++] = 0;
75 memcpy(buffer + offset, sha1, 20);
76 offset += 20;
77 nr++;
78 }
79
80 write_sha1_file(buffer, offset, "tree", returnsha1);
81 free(buffer);
82 return nr;
83 }
84
85 int main(int argc, char **argv)
86 {
87 int i, funny;
88 int entries = read_cache();
89 unsigned char sha1[20];
90
91 if (entries < 0)
92 die("git-write-tree: error reading cache");
93
94 /* Verify that the tree is merged */
95 funny = 0;
96 for (i = 0; i < entries; i++) {
97 struct cache_entry *ce = active_cache[i];
98 if (ntohs(ce->ce_flags) & ~CE_NAMEMASK) {
99 if (10 < ++funny) {
100 fprintf(stderr, "...\n");
101 break;
102 }
103 fprintf(stderr, "%s: unmerged (%s)\n", ce->name, sha1_to_hex(ce->sha1));
104 }
105 }
106 if (funny)
107 die("git-write-tree: not able to write tree");
108
109 /* Also verify that the cache does not have path and path/file
110 * at the same time. At this point we know the cache has only
111 * stage 0 entries.
112 */
113 funny = 0;
114 for (i = 0; i < entries - 1; i++) {
115 /* path/file always comes after path because of the way
116 * the cache is sorted. Also path can appear only once,
117 * which means conflicting one would immediately follow.
118 */
119 const char *this_name = active_cache[i]->name;
120 const char *next_name = active_cache[i+1]->name;
121 int this_len = strlen(this_name);
122 if (this_len < strlen(next_name) &&
123 strncmp(this_name, next_name, this_len) == 0 &&
124 next_name[this_len] == '/') {
125 if (10 < ++funny) {
126 fprintf(stderr, "...\n");
127 break;
128 }
129 fprintf(stderr, "You have both %s and %s\n",
130 this_name, next_name);
131 }
132 }
133 if (funny)
134 die("git-write-tree: not able to write tree");
135
136 /* Ok, write it out */
137 if (write_tree(active_cache, entries, "", 0, sha1) != entries)
138 die("git-write-tree: internal error");
139 printf("%s\n", sha1_to_hex(sha1));
140 return 0;
141 }