patch-id.con commit git-svn: correctly track diff-less copies with do_switch (2fa6a23)
   1#include "cache.h"
   2
   3static void flush_current_id(int patchlen, unsigned char *id, SHA_CTX *c)
   4{
   5        unsigned char result[20];
   6        char name[50];
   7
   8        if (!patchlen)
   9                return;
  10
  11        SHA1_Final(result, c);
  12        memcpy(name, sha1_to_hex(id), 41);
  13        printf("%s %s\n", sha1_to_hex(result), name);
  14        SHA1_Init(c);
  15}
  16
  17static int remove_space(char *line)
  18{
  19        char *src = line;
  20        char *dst = line;
  21        unsigned char c;
  22
  23        while ((c = *src++) != '\0') {
  24                if (!isspace(c))
  25                        *dst++ = c;
  26        }
  27        return dst - line;
  28}
  29
  30static void generate_id_list(void)
  31{
  32        static unsigned char sha1[20];
  33        static char line[1000];
  34        SHA_CTX ctx;
  35        int patchlen = 0;
  36
  37        SHA1_Init(&ctx);
  38        while (fgets(line, sizeof(line), stdin) != NULL) {
  39                unsigned char n[20];
  40                char *p = line;
  41                int len;
  42
  43                if (!memcmp(line, "diff-tree ", 10))
  44                        p += 10;
  45                else if (!memcmp(line, "commit ", 7))
  46                        p += 7;
  47
  48                if (!get_sha1_hex(p, n)) {
  49                        flush_current_id(patchlen, sha1, &ctx);
  50                        hashcpy(sha1, n);
  51                        patchlen = 0;
  52                        continue;
  53                }
  54
  55                /* Ignore commit comments */
  56                if (!patchlen && memcmp(line, "diff ", 5))
  57                        continue;
  58
  59                /* Ignore git-diff index header */
  60                if (!memcmp(line, "index ", 6))
  61                        continue;
  62
  63                /* Ignore line numbers when computing the SHA1 of the patch */
  64                if (!memcmp(line, "@@ -", 4))
  65                        continue;
  66
  67                /* Compute the sha without whitespace */
  68                len = remove_space(line);
  69                patchlen += len;
  70                SHA1_Update(&ctx, line, len);
  71        }
  72        flush_current_id(patchlen, sha1, &ctx);
  73}
  74
  75static const char patch_id_usage[] = "git-patch-id < patch";
  76
  77int main(int argc, char **argv)
  78{
  79        if (argc != 1)
  80                usage(patch_id_usage);
  81
  82        generate_id_list();
  83        return 0;
  84}