show-diff.c

   1 /*
   2  * GIT - The information manager from hell
   3  *
   4  * Copyright (C) Linus Torvalds, 2005
   5  */
   6 #include "cache.h"
   7
   8 static void show_differences(char *name,
   9         void *old_contents, unsigned long long old_size)
  10 {
  11         static char cmd[1000];
  12         FILE *f;
  13
  14         snprintf(cmd, sizeof(cmd), "diff -L %s -u -N  - %s", name, name);
  15         f = popen(cmd, "w");
  16         if (old_size)
  17                 fwrite(old_contents, old_size, 1, f);
  18         pclose(f);
  19 }
  20
  21 static void show_diff_empty(struct cache_entry *ce)
  22 {
  23         char *old;
  24         unsigned long int size;
  25         int lines=0;
  26         unsigned char type[20], *p, *end;
  27
  28         old = read_sha1_file(ce->sha1, type, &size);
  29         if (size > 0) {
  30                 int startline = 1;
  31                 int c = 0;
  32
  33                 printf("--- %s\n", ce->name);
  34                 printf("+++ %s\n", ce->name);
  35                 p = old;
  36                 end = old + size;
  37                 while (p < end)
  38                         if (*p++ == '\n')
  39                                 lines ++;
  40                 printf("@@ -1,%d +0,0 @@\n", lines);
  41                 p = old;
  42                 while (p < end) {
  43                         c = *p++;
  44                         if (startline) {
  45                                 putchar('-');
  46                                 startline = 0;
  47                         }
  48                         putchar(c);
  49                         if (c == '\n')
  50                                 startline = 1;
  51                 }
  52                 if (c!='\n')
  53                         printf("\n");
  54                 fflush(stdout);
  55         }
  56 }
  57
  58 int main(int argc, char **argv)
  59 {
  60         int entries = read_cache();
  61         int i;
  62
  63         if (entries < 0) {
  64                 perror("read_cache");
  65                 exit(1);
  66         }
  67         for (i = 0; i < entries; i++) {
  68                 struct stat st;
  69                 struct cache_entry *ce = active_cache[i];
  70                 int n, changed;
  71                 unsigned long size;
  72                 char type[20];
  73                 void *new;
  74
  75                 if (stat(ce->name, &st) < 0) {
  76                         printf("%s: %s\n", ce->name, strerror(errno));
  77                         if (errno ==  ENOENT)
  78                                 show_diff_empty(ce);
  79                         continue;
  80                 }
  81                 changed = cache_match_stat(ce, &st);
  82                 if (!changed)
  83                         continue;
  84                 printf("%.*s:  ", ce->namelen, ce->name);
  85                 for (n = 0; n < 20; n++)
  86                         printf("%02x", ce->sha1[n]);
  87                 printf("\n");
  88                 fflush(stdout);
  89                 new = read_sha1_file(ce->sha1, type, &size);
  90                 show_differences(ce->name, new, size);
  91                 free(new);
  92         }
  93         return 0;
  94 }