[PATCH] git-peek-remote: show tags and heads from a remote repository.
[git.git] / patch-id.c
1 #include <ctype.h>
2 #include "cache.h"
3
4 static void flush_current_id(int patchlen, unsigned char *id, SHA_CTX *c)
5 {
6         unsigned char result[20];
7         char name[50];
8
9         if (!patchlen)
10                 return;
11
12         SHA1_Final(result, c);
13         memcpy(name, sha1_to_hex(id), 41);
14         printf("%s %s\n", sha1_to_hex(result), name);
15         SHA1_Init(c);
16 }
17
18 static int remove_space(char *line)
19 {
20         char *src = line;
21         char *dst = line;
22         unsigned char c;
23
24         while ((c = *src++) != '\0') {
25                 if (!isspace(c))
26                         *dst++ = c;
27         }
28         return dst - line;
29 }
30
31 static void generate_id_list(void)
32 {
33         static unsigned char sha1[20];
34         static char line[1000];
35         SHA_CTX ctx;
36         int patchlen = 0;
37
38         SHA1_Init(&ctx);
39         while (fgets(line, sizeof(line), stdin) != NULL) {
40                 unsigned char n[20];
41                 char *p = line;
42                 int len;
43
44                 if (!memcmp(line, "diff-tree ", 10))
45                         p += 10;
46
47                 if (!get_sha1_hex(p, n)) {
48                         flush_current_id(patchlen, sha1, &ctx);
49                         memcpy(sha1, n, 20);
50                         patchlen = 0;
51                         continue;
52                 }
53
54                 /* Ignore commit comments */
55                 if (!patchlen && memcmp(line, "diff ", 5))
56                         continue;
57
58                 /* Ignore line numbers when computing the SHA1 of the patch */
59                 if (!memcmp(line, "@@ -", 4))
60                         continue;
61
62                 /* Compute the sha without whitespace */
63                 len = remove_space(line);
64                 patchlen += len;
65                 SHA1_Update(&ctx, line, len);
66         }
67         flush_current_id(patchlen, sha1, &ctx);
68 }
69
70 static const char patch_id_usage[] = "usage: git-patch-id < patch";
71
72 int main(int argc, char **argv)
73 {
74         if (argc != 1)
75                 usage(patch_id_usage);
76
77         generate_id_list();
78         return 0;
79 }