diff-helper.c

   1 /*
   2  * Copyright (C) 2005 Junio C Hamano
   3  */
   4 #include <limits.h>
   5 #include "cache.h"
   6 #include "strbuf.h"
   7 #include "diff.h"
   8
   9 static int matches_pathspec(const char *name, const char **spec, int cnt)
  10 {
  11         int i;
  12         int namelen = strlen(name);
  13         for (i = 0; i < cnt; i++) {
  14                 int speclen = strlen(spec[i]);
  15                 if (! strncmp(spec[i], name, speclen) &&
  16                     speclen <= namelen &&
  17                     (name[speclen] == 0 ||
  18                      name[speclen] == '/'))
  19                         return 1;
  20         }
  21         return 0;
  22 }
  23
  24 static int parse_oneside_change(const char *cp, struct diff_spec *one,
  25                                 char *path)
  26 {
  27         int ch;
  28
  29         one->file_valid = one->sha1_valid = 1;
  30         one->mode = 0;
  31         while ((ch = *cp) && '0' <= ch && ch <= '7') {
  32                 one->mode = (one->mode << 3) | (ch - '0');
  33                 cp++;
  34         }
  35
  36         if (strncmp(cp, "\tblob\t", 6))
  37                 return -1;
  38         cp += 6;
  39         if (get_sha1_hex(cp, one->blob_sha1))
  40                 return -1;
  41         cp += 40;
  42         if (*cp++ != '\t')
  43                 return -1;
  44         strcpy(path, cp);
  45         return 0;
  46 }
  47
  48 static int parse_diff_raw_output(const char *buf,
  49                                  const char **spec, int cnt, int reverse)
  50 {
  51         struct diff_spec old, new;
  52         char path[PATH_MAX];
  53         const char *cp = buf;
  54         int ch;
  55
  56         switch (*cp++) {
  57         case 'U':
  58                 if (!cnt || matches_pathspec(cp + 1, spec, cnt))
  59                         diff_unmerge(cp + 1);
  60                 return 0;
  61         case '+':
  62                 old.file_valid = 0;
  63                 parse_oneside_change(cp, &new, path);
  64                 break;
  65         case '-':
  66                 new.file_valid = 0;
  67                 parse_oneside_change(cp, &old, path);
  68                 break;
  69         case '*':
  70                 old.file_valid = old.sha1_valid =
  71                         new.file_valid = new.sha1_valid = 1;
  72                 old.mode = new.mode = 0;
  73                 while ((ch = *cp) && ('0' <= ch && ch <= '7')) {
  74                         old.mode = (old.mode << 3) | (ch - '0');
  75                         cp++;
  76                 }
  77                 if (strncmp(cp, "->", 2))
  78                         return -1;
  79                 cp += 2;
  80                 while ((ch = *cp) && ('0' <= ch && ch <= '7')) {
  81                         new.mode = (new.mode << 3) | (ch - '0');
  82                         cp++;
  83                 }
  84                 if (strncmp(cp, "\tblob\t", 6))
  85                         return -1;
  86                 cp += 6;
  87                 if (get_sha1_hex(cp, old.blob_sha1))
  88                         return -1;
  89                 cp += 40;
  90                 if (strncmp(cp, "->", 2))
  91                         return -1;
  92                 cp += 2;
  93                 if (get_sha1_hex(cp, new.blob_sha1))
  94                         return -1;
  95                 cp += 40;
  96                 if (*cp++ != '\t')
  97                         return -1;
  98                 strcpy(path, cp);
  99                 break;
 100         default:
 101                 return -1;
 102         }
 103         if (!cnt || matches_pathspec(path, spec, cnt)) {
 104                 if (reverse)
 105                         run_external_diff(path, &new, &old);
 106                 else
 107                         run_external_diff(path, &old, &new);
 108         }
 109         return 0;
 110 }
 111
 112 static const char *diff_helper_usage =
 113 "git-diff-helper [-R] [-z] paths...";
 114
 115 int main(int ac, const char **av) {
 116         struct strbuf sb;
 117         int reverse = 0;
 118         int line_termination = '\n';
 119
 120         strbuf_init(&sb);
 121
 122         while (1 < ac && av[1][0] == '-') {
 123                 if (av[1][1] == 'R')
 124                         reverse = 1;
 125                 else if (av[1][1] == 'z')
 126                         line_termination = 0;
 127                 else
 128                         usage(diff_helper_usage);
 129                 ac--; av++;
 130         }
 131         /* the remaining parameters are paths patterns */
 132
 133         while (1) {
 134                 int status;
 135                 read_line(&sb, stdin, line_termination);
 136                 if (sb.eof)
 137                         break;
 138                 status = parse_diff_raw_output(sb.buf, av+1, ac-1, reverse);
 139                 if (status)
 140                         fprintf(stderr, "cannot parse %s\n", sb.buf);
 141         }
 142         return 0;
 143 }