show-diff: match diff-tree and diff-cache output
[git/fastimport.git] / diff-tree-helper.c
blobbcf89a57892ac3601ac268b08c7f28d443c75108
1 /*
2 * Copyright (C) 2005 Junio C Hamano
3 */
4 #include "cache.h"
5 #include "strbuf.h"
6 #include "diff.h"
8 static int matches_pathspec(const char *name, char **spec, int cnt)
10 int i;
11 int namelen = strlen(name);
12 for (i = 0; i < cnt; i++) {
13 int speclen = strlen(spec[i]);
14 if (! strncmp(spec[i], name, speclen) &&
15 speclen <= namelen &&
16 (name[speclen] == 0 ||
17 name[speclen] == '/'))
18 return 1;
20 return 0;
23 static int parse_oneside_change(const char *cp, struct diff_spec *one,
24 char *path)
26 int ch;
28 one->file_valid = one->sha1_valid = 1;
29 one->mode = 0;
30 while ((ch = *cp) && '0' <= ch && ch <= '7') {
31 one->mode = (one->mode << 3) | (ch - '0');
32 cp++;
35 if (strncmp(cp, "\tblob\t", 6))
36 return -1;
37 cp += 6;
38 if (get_sha1_hex(cp, one->u.sha1))
39 return -1;
40 cp += 40;
41 if (*cp++ != '\t')
42 return -1;
43 strcpy(path, cp);
44 return 0;
47 static int parse_diff_tree_output(const char *buf,
48 struct diff_spec *old,
49 struct diff_spec *new,
50 char *path) {
51 const char *cp = buf;
52 int ch;
54 switch (*cp++) {
55 case '+':
56 old->file_valid = 0;
57 return parse_oneside_change(cp, new, path);
58 case '-':
59 new->file_valid = 0;
60 return parse_oneside_change(cp, old, path);
61 case '*':
62 break;
63 default:
64 return -1;
67 /* This is for '*' entries */
68 old->file_valid = old->sha1_valid = 1;
69 new->file_valid = new->sha1_valid = 1;
71 old->mode = new->mode = 0;
72 while ((ch = *cp) && ('0' <= ch && ch <= '7')) {
73 old->mode = (old->mode << 3) | (ch - '0');
74 cp++;
76 if (strncmp(cp, "->", 2))
77 return -1;
78 cp += 2;
79 while ((ch = *cp) && ('0' <= ch && ch <= '7')) {
80 new->mode = (new->mode << 3) | (ch - '0');
81 cp++;
83 if (strncmp(cp, "\tblob\t", 6))
84 return -1;
85 cp += 6;
86 if (get_sha1_hex(cp, old->u.sha1))
87 return -1;
88 cp += 40;
89 if (strncmp(cp, "->", 2))
90 return -1;
91 cp += 2;
92 if (get_sha1_hex(cp, new->u.sha1))
93 return -1;
94 cp += 40;
95 if (*cp++ != '\t')
96 return -1;
97 strcpy(path, cp);
98 return 0;
101 static const char *diff_tree_helper_usage =
102 "diff-tree-helper [-R] [-z] paths...";
104 int main(int ac, char **av) {
105 struct strbuf sb;
106 int reverse_diff = 0;
107 int line_termination = '\n';
109 strbuf_init(&sb);
111 while (1 < ac && av[1][0] == '-') {
112 if (av[1][1] == 'R')
113 reverse_diff = 1;
114 else if (av[1][1] == 'z')
115 line_termination = 0;
116 else
117 usage(diff_tree_helper_usage);
118 ac--; av++;
120 /* the remaining parameters are paths patterns */
122 while (1) {
123 struct diff_spec old, new;
124 char path[PATH_MAX];
125 read_line(&sb, stdin, line_termination);
126 if (sb.eof)
127 break;
128 if (parse_diff_tree_output(sb.buf, &old, &new, path)) {
129 fprintf(stderr, "cannot parse %s\n", sb.buf);
130 continue;
132 if (1 < ac && !matches_pathspec(path, av+1, ac-1))
133 continue;
135 run_external_diff(path, &old, &new);
137 return 0;