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 detect_rename = 0;
  10 static int diff_score_opt = 0;
  11 static int generate_patch = 1;
  12
  13 static int parse_oneside_change(const char *cp, int *mode,
  14                                 unsigned char *sha1, char *path)
  15 {
  16         int ch, m;
  17
  18         m = 0;
  19         while ((ch = *cp) && '0' <= ch && ch <= '7') {
  20                 m = (m << 3) | (ch - '0');
  21                 cp++;
  22         }
  23         *mode = m;
  24         if (strncmp(cp, "\tblob\t", 6) && strncmp(cp, " blob ", 6) &&
  25             strncmp(cp, "\ttree\t", 6) && strncmp(cp, " tree ", 6))
  26                 return -1;
  27         cp += 6;
  28         if (get_sha1_hex(cp, sha1))
  29                 return -1;
  30         cp += 40;
  31         if ((*cp != '\t') && *cp != ' ')
  32                 return -1;
  33         strcpy(path, ++cp);
  34         return 0;
  35 }
  36
  37 static int parse_diff_raw_output(const char *buf)
  38 {
  39         char path[PATH_MAX];
  40         unsigned char old_sha1[20], new_sha1[20];
  41         const char *cp = buf;
  42         int ch, old_mode, new_mode;
  43
  44         switch (*cp++) {
  45         case 'U':
  46                 diff_unmerge(cp + 1);
  47                 break;
  48         case '+':
  49                 if (parse_oneside_change(cp, &new_mode, new_sha1, path))
  50                         return -1;
  51                 diff_addremove('+', new_mode, new_sha1, path, NULL);
  52                 break;
  53         case '-':
  54                 if (parse_oneside_change(cp, &old_mode, old_sha1, path))
  55                         return -1;
  56                 diff_addremove('-', old_mode, old_sha1, path, NULL);
  57                 break;
  58         case '*':
  59                 old_mode = new_mode = 0;
  60                 while ((ch = *cp) && ('0' <= ch && ch <= '7')) {
  61                         old_mode = (old_mode << 3) | (ch - '0');
  62                         cp++;
  63                 }
  64                 if (strncmp(cp, "->", 2))
  65                         return -1;
  66                 cp += 2;
  67                 while ((ch = *cp) && ('0' <= ch && ch <= '7')) {
  68                         new_mode = (new_mode << 3) | (ch - '0');
  69                         cp++;
  70                 }
  71                 if (strncmp(cp, "\tblob\t", 6) && strncmp(cp, " blob ", 6) &&
  72                     strncmp(cp, "\ttree\t", 6) && strncmp(cp, " tree ", 6))
  73                         return -1;
  74                 cp += 6;
  75                 if (get_sha1_hex(cp, old_sha1))
  76                         return -1;
  77                 cp += 40;
  78                 if (strncmp(cp, "->", 2))
  79                         return -1;
  80                 cp += 2;
  81                 if (get_sha1_hex(cp, new_sha1))
  82                         return -1;
  83                 cp += 40;
  84                 if ((*cp != '\t') && *cp != ' ')
  85                         return -1;
  86                 strcpy(path, ++cp);
  87                 diff_change(old_mode, new_mode, old_sha1, new_sha1, path, NULL);
  88                 break;
  89         default:
  90                 return -1;
  91         }
  92         return 0;
  93 }
  94
  95 static const char *diff_helper_usage =
  96         "git-diff-helper [-z] [-R] [-M] [-C] paths...";
  97
  98 int main(int ac, const char **av) {
  99         struct strbuf sb;
 100         int reverse = 0;
 101         int line_termination = '\n';
 102
 103         strbuf_init(&sb);
 104
 105         while (1 < ac && av[1][0] == '-') {
 106                 if (av[1][1] == 'R')
 107                         reverse = 1;
 108                 else if (av[1][1] == 'z')
 109                         line_termination = 0;
 110                 else if (av[1][1] == 'p') /* hidden from the help */
 111                         generate_patch = 0;
 112                 else if (av[1][1] == 'M') {
 113                         detect_rename = 1;
 114                         diff_score_opt = diff_scoreopt_parse(av[1]);
 115                 }
 116                 else if (av[1][1] == 'C') {
 117                         detect_rename = 2;
 118                         diff_score_opt = diff_scoreopt_parse(av[1]);
 119                 }
 120                 else
 121                         usage(diff_helper_usage);
 122                 ac--; av++;
 123         }
 124         /* the remaining parameters are paths patterns */
 125
 126         diff_setup(detect_rename, diff_score_opt, reverse,
 127                    (generate_patch ? -1 : line_termination),
 128                    av+1, ac-1);
 129
 130         while (1) {
 131                 int status;
 132                 read_line(&sb, stdin, line_termination);
 133                 if (sb.eof)
 134                         break;
 135                 status = parse_diff_raw_output(sb.buf);
 136                 if (status) {
 137                         diff_flush();
 138                         printf("%s%c", sb.buf, line_termination);
 139                 }
 140         }
 141
 142         diff_flush();
 143         return 0;
 144 }