Optimize common case of git-rev-list
[git/gitweb.git] / write-tree.c
blob2b2c6b77afd53870423d4bad9191ed669bc55660
1 /*
2 * GIT - The information manager from hell
4 * Copyright (C) Linus Torvalds, 2005
5 */
6 #include "cache.h"
8 static int missing_ok = 0;
10 static int check_valid_sha1(unsigned char *sha1)
12 int ret;
14 /* If we were anal, we'd check that the sha1 of the contents actually matches */
15 ret = has_sha1_file(sha1);
16 if (ret == 0)
17 perror(sha1_file_name(sha1));
18 return ret ? 0 : -1;
21 static int write_tree(struct cache_entry **cachep, int maxentries, const char *base, int baselen, unsigned char *returnsha1)
23 unsigned char subdir_sha1[20];
24 unsigned long size, offset;
25 char *buffer;
26 int nr;
28 /* Guess at some random initial size */
29 size = 8192;
30 buffer = xmalloc(size);
31 offset = 0;
33 nr = 0;
34 while (nr < maxentries) {
35 struct cache_entry *ce = cachep[nr];
36 const char *pathname = ce->name, *filename, *dirname;
37 int pathlen = ce_namelen(ce), entrylen;
38 unsigned char *sha1;
39 unsigned int mode;
41 /* Did we hit the end of the directory? Return how many we wrote */
42 if (baselen >= pathlen || memcmp(base, pathname, baselen))
43 break;
45 sha1 = ce->sha1;
46 mode = ntohl(ce->ce_mode);
48 /* Do we have _further_ subdirectories? */
49 filename = pathname + baselen;
50 dirname = strchr(filename, '/');
51 if (dirname) {
52 int subdir_written;
54 subdir_written = write_tree(cachep + nr, maxentries - nr, pathname, dirname-pathname+1, subdir_sha1);
55 nr += subdir_written;
57 /* Now we need to write out the directory entry into this tree.. */
58 mode = S_IFDIR;
59 pathlen = dirname - pathname;
61 /* ..but the directory entry doesn't count towards the total count */
62 nr--;
63 sha1 = subdir_sha1;
66 if (!missing_ok && check_valid_sha1(sha1) < 0)
67 exit(1);
69 entrylen = pathlen - baselen;
70 if (offset + entrylen + 100 > size) {
71 size = alloc_nr(offset + entrylen + 100);
72 buffer = xrealloc(buffer, size);
74 offset += sprintf(buffer + offset, "%o %.*s", mode, entrylen, filename);
75 buffer[offset++] = 0;
76 memcpy(buffer + offset, sha1, 20);
77 offset += 20;
78 nr++;
81 write_sha1_file(buffer, offset, "tree", returnsha1);
82 free(buffer);
83 return nr;
86 int main(int argc, char **argv)
88 int i, funny;
89 int entries = read_cache();
90 unsigned char sha1[20];
92 if (argc == 2) {
93 if (!strcmp(argv[1], "--missing-ok"))
94 missing_ok = 1;
95 else
96 die("unknown option %s", argv[1]);
99 if (argc > 2)
100 die("too many options");
102 if (entries < 0)
103 die("git-write-tree: error reading cache");
105 /* Verify that the tree is merged */
106 funny = 0;
107 for (i = 0; i < entries; i++) {
108 struct cache_entry *ce = active_cache[i];
109 if (ntohs(ce->ce_flags) & ~CE_NAMEMASK) {
110 if (10 < ++funny) {
111 fprintf(stderr, "...\n");
112 break;
114 fprintf(stderr, "%s: unmerged (%s)\n", ce->name, sha1_to_hex(ce->sha1));
117 if (funny)
118 die("git-write-tree: not able to write tree");
120 /* Also verify that the cache does not have path and path/file
121 * at the same time. At this point we know the cache has only
122 * stage 0 entries.
124 funny = 0;
125 for (i = 0; i < entries - 1; i++) {
126 /* path/file always comes after path because of the way
127 * the cache is sorted. Also path can appear only once,
128 * which means conflicting one would immediately follow.
130 const char *this_name = active_cache[i]->name;
131 const char *next_name = active_cache[i+1]->name;
132 int this_len = strlen(this_name);
133 if (this_len < strlen(next_name) &&
134 strncmp(this_name, next_name, this_len) == 0 &&
135 next_name[this_len] == '/') {
136 if (10 < ++funny) {
137 fprintf(stderr, "...\n");
138 break;
140 fprintf(stderr, "You have both %s and %s\n",
141 this_name, next_name);
144 if (funny)
145 die("git-write-tree: not able to write tree");
147 /* Ok, write it out */
148 if (write_tree(active_cache, entries, "", 0, sha1) != entries)
149 die("git-write-tree: internal error");
150 printf("%s\n", sha1_to_hex(sha1));
151 return 0;