Fix up git-fsck-cache documentation
[git] / diff-helper.c
1 /*
2  * Copyright (C) 2005 Junio C Hamano
3  */
4 #include "cache.h"
5 #include "strbuf.h"
6 #include "diff.h"
7
8 static int detect_rename = 0;
9 static int diff_score_opt = 0;
10 static const char *pickaxe = NULL;
11 static int diff_output_style = DIFF_FORMAT_PATCH;
12 static int line_termination = '\n';
13 static int inter_name_termination = '\t';
14
15 static int parse_diff_raw(char *buf1, char *buf2, char *buf3)
16 {
17         char old_path[PATH_MAX];
18         unsigned char old_sha1[20], new_sha1[20];
19         char *ep;
20         char *cp = buf1;
21         int ch, old_mode, new_mode;
22
23         old_mode = new_mode = 0;
24         while ((ch = *cp) && ('0' <= ch && ch <= '7')) {
25                 old_mode = (old_mode << 3) | (ch - '0');
26                 cp++;
27         }
28         if (*cp++ != ' ')
29                 return -1;
30         while ((ch = *cp) && ('0' <= ch && ch <= '7')) {
31                 new_mode = (new_mode << 3) | (ch - '0');
32                 cp++;
33         }
34         if (*cp++ != ' ')
35                 return -1;
36         if (get_sha1_hex(cp, old_sha1))
37                 return -1;
38         cp += 40;
39         if (*cp++ != ' ')
40                 return -1;
41         if (get_sha1_hex(cp, new_sha1))
42                 return -1;
43         cp += 40;
44         if (*cp++ != inter_name_termination)
45                 return -1;
46         if (buf2)
47                 cp = buf2;
48         ep = strchr(cp, inter_name_termination);
49         if (!ep)
50                 return -1;
51         *ep++ = 0;
52         strcpy(old_path, cp);
53         diff_guif(old_mode, new_mode, old_sha1, new_sha1,
54                   old_path, buf3 ? buf3 : ep);
55         return 0;
56 }
57
58 static const char *diff_helper_usage =
59         "git-diff-helper [-z] [-R] [-M] [-C] [-S<string>] paths...";
60
61 int main(int ac, const char **av) {
62         struct strbuf sb1, sb2, sb3;
63         int reverse_diff = 0;
64
65         strbuf_init(&sb1);
66         strbuf_init(&sb2);
67         strbuf_init(&sb3);
68
69         while (1 < ac && av[1][0] == '-') {
70                 if (av[1][1] == 'R')
71                         reverse_diff = 1;
72                 else if (av[1][1] == 'z')
73                         line_termination = inter_name_termination = 0;
74                 else if (av[1][1] == 'p') /* hidden from the help */
75                         diff_output_style = DIFF_FORMAT_HUMAN;
76                 else if (av[1][1] == 'P') /* hidden from the help */
77                         diff_output_style = DIFF_FORMAT_MACHINE;
78                 else if (av[1][1] == 'M') {
79                         detect_rename = DIFF_DETECT_RENAME;
80                         diff_score_opt = diff_scoreopt_parse(av[1]);
81                 }
82                 else if (av[1][1] == 'C') {
83                         detect_rename = DIFF_DETECT_COPY;
84                         diff_score_opt = diff_scoreopt_parse(av[1]);
85                 }
86                 else if (av[1][1] == 'S') {
87                         pickaxe = av[1] + 2;
88                 }
89                 else
90                         usage(diff_helper_usage);
91                 ac--; av++;
92         }
93         /* the remaining parameters are paths patterns */
94
95         diff_setup(reverse_diff);
96         while (1) {
97                 int status;
98                 read_line(&sb1, stdin, line_termination);
99                 if (sb1.eof)
100                         break;
101                 switch (sb1.buf[0]) {
102                 case 'U':
103                         diff_unmerge(sb1.buf + 2);
104                         continue;
105                 case ':':
106                         break;
107                 default:
108                         goto unrecognized;
109                 }
110                 if (!line_termination) {
111                         read_line(&sb2, stdin, line_termination);
112                         if (sb2.eof)
113                                 break;
114                         read_line(&sb3, stdin, line_termination);
115                         if (sb3.eof)
116                                 break;
117                         status = parse_diff_raw(sb1.buf+1, sb2.buf, sb3.buf);
118                 }
119                 else
120                         status = parse_diff_raw(sb1.buf+1, NULL, NULL);
121                 if (status) {
122                 unrecognized:
123                         diff_flush(diff_output_style);
124                         printf("%s%c", sb1.buf, line_termination);
125                 }
126         }
127         if (detect_rename)
128                 diffcore_rename(detect_rename, diff_score_opt);
129         diffcore_prune();
130         if (pickaxe)
131                 diffcore_pickaxe(pickaxe);
132         if (ac)
133                 diffcore_pathspec(av + 1);
134         diff_flush(diff_output_style);
135         return 0;
136 }