patch-id.c

   1 #include "cache.h"
   2 #include "exec_cmd.h"
   3
   4 static void flush_current_id(int patchlen, unsigned char *id, git_SHA_CTX *c)
   5 {
   6         unsigned char result[20];
   7         char name[50];
   8
   9         if (!patchlen)
  10                 return;
  11
  12         git_SHA1_Final(result, c);
  13         memcpy(name, sha1_to_hex(id), 41);
  14         printf("%s %s\n", sha1_to_hex(result), name);
  15         git_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         git_SHA_CTX ctx;
  36         int patchlen = 0;
  37
  38         git_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                 else if (!memcmp(line, "commit ", 7))
  47                         p += 7;
  48
  49                 if (!get_sha1_hex(p, n)) {
  50                         flush_current_id(patchlen, sha1, &ctx);
  51                         hashcpy(sha1, n);
  52                         patchlen = 0;
  53                         continue;
  54                 }
  55
  56                 /* Ignore commit comments */
  57                 if (!patchlen && memcmp(line, "diff ", 5))
  58                         continue;
  59
  60                 /* Ignore git-diff index header */
  61                 if (!memcmp(line, "index ", 6))
  62                         continue;
  63
  64                 /* Ignore line numbers when computing the SHA1 of the patch */
  65                 if (!memcmp(line, "@@ -", 4))
  66                         continue;
  67
  68                 /* Compute the sha without whitespace */
  69                 len = remove_space(line);
  70                 patchlen += len;
  71                 git_SHA1_Update(&ctx, line, len);
  72         }
  73         flush_current_id(patchlen, sha1, &ctx);
  74 }
  75
  76 static const char patch_id_usage[] = "git patch-id < patch";
  77
  78 int main(int argc, char **argv)
  79 {
  80         if (argc != 1)
  81                 usage(patch_id_usage);
  82
  83         git_extract_argv0_path(argv[0]);
  84
  85         generate_id_list();
  86         return 0;
  87 }