Add Documentation/technical/pack-format.txt
[alt-git.git] / commit-tree.c
blob2d8651894a20e752eb47e6da439ad3cee13c29c4
1 /*
2 * GIT - The information manager from hell
4 * Copyright (C) Linus Torvalds, 2005
5 */
6 #include "cache.h"
7 #include "commit.h"
8 #include "tree.h"
10 #define BLOCKING (1ul << 14)
13 * FIXME! Share the code with "write-tree.c"
15 static void init_buffer(char **bufp, unsigned int *sizep)
17 char *buf = xmalloc(BLOCKING);
18 *sizep = 0;
19 *bufp = buf;
22 static void add_buffer(char **bufp, unsigned int *sizep, const char *fmt, ...)
24 char one_line[2048];
25 va_list args;
26 int len;
27 unsigned long alloc, size, newsize;
28 char *buf;
30 va_start(args, fmt);
31 len = vsnprintf(one_line, sizeof(one_line), fmt, args);
32 va_end(args);
33 size = *sizep;
34 newsize = size + len;
35 alloc = (size + 32767) & ~32767;
36 buf = *bufp;
37 if (newsize > alloc) {
38 alloc = (newsize + 32767) & ~32767;
39 buf = xrealloc(buf, alloc);
40 *bufp = buf;
42 *sizep = newsize;
43 memcpy(buf + size, one_line, len);
46 static void check_valid(unsigned char *sha1, const char *expect)
48 void *buf;
49 char type[20];
50 unsigned long size;
52 buf = read_sha1_file(sha1, type, &size);
53 if (!buf || strcmp(type, expect))
54 die("%s is not a valid '%s' object", sha1_to_hex(sha1), expect);
55 free(buf);
59 * Having more than two parents is not strange at all, and this is
60 * how multi-way merges are represented.
62 #define MAXPARENT (16)
63 static unsigned char parent_sha1[MAXPARENT][20];
65 static const char commit_tree_usage[] = "git-commit-tree <sha1> [-p <sha1>]* < changelog";
67 static int new_parent(int idx)
69 int i;
70 unsigned char *sha1 = parent_sha1[idx];
71 for (i = 0; i < idx; i++) {
72 if (!memcmp(parent_sha1[i], sha1, 20)) {
73 error("duplicate parent %s ignored", sha1_to_hex(sha1));
74 return 0;
77 return 1;
80 int main(int argc, char **argv)
82 int i;
83 int parents = 0;
84 unsigned char tree_sha1[20];
85 unsigned char commit_sha1[20];
86 char comment[1000];
87 char *buffer;
88 unsigned int size;
90 setup_ident();
91 setup_git_directory();
93 git_config(git_default_config);
95 if (argc < 2 || get_sha1_hex(argv[1], tree_sha1) < 0)
96 usage(commit_tree_usage);
98 check_valid(tree_sha1, tree_type);
99 for (i = 2; i < argc; i += 2) {
100 char *a, *b;
101 a = argv[i]; b = argv[i+1];
102 if (!b || strcmp(a, "-p") || get_sha1(b, parent_sha1[parents]))
103 usage(commit_tree_usage);
104 check_valid(parent_sha1[parents], commit_type);
105 if (new_parent(parents))
106 parents++;
108 if (!parents)
109 fprintf(stderr, "Committing initial tree %s\n", argv[1]);
111 init_buffer(&buffer, &size);
112 add_buffer(&buffer, &size, "tree %s\n", sha1_to_hex(tree_sha1));
115 * NOTE! This ordering means that the same exact tree merged with a
116 * different order of parents will be a _different_ changeset even
117 * if everything else stays the same.
119 for (i = 0; i < parents; i++)
120 add_buffer(&buffer, &size, "parent %s\n", sha1_to_hex(parent_sha1[i]));
122 /* Person/date information */
123 add_buffer(&buffer, &size, "author %s\n", git_author_info(1));
124 add_buffer(&buffer, &size, "committer %s\n\n", git_committer_info(1));
126 /* And add the comment */
127 while (fgets(comment, sizeof(comment), stdin) != NULL)
128 add_buffer(&buffer, &size, "%s", comment);
130 if (!write_sha1_file(buffer, size, commit_type, commit_sha1)) {
131 printf("%s\n", sha1_to_hex(commit_sha1));
132 return 0;
134 else
135 return 1;