autoconf: don't use platform regex if it lacks REG_STARTEND
[git] / diff-no-index.c
1 /*
2  * "diff --no-index" support
3  * Copyright (c) 2007 by Johannes Schindelin
4  * Copyright (c) 2008 by Junio C Hamano
5  */
6
7 #include "cache.h"
8 #include "color.h"
9 #include "commit.h"
10 #include "blob.h"
11 #include "tag.h"
12 #include "diff.h"
13 #include "diffcore.h"
14 #include "revision.h"
15 #include "log-tree.h"
16 #include "builtin.h"
17 #include "string-list.h"
18
19 static int read_directory(const char *path, struct string_list *list)
20 {
21         DIR *dir;
22         struct dirent *e;
23
24         if (!(dir = opendir(path)))
25                 return error("Could not open directory %s", path);
26
27         while ((e = readdir(dir)))
28                 if (strcmp(".", e->d_name) && strcmp("..", e->d_name))
29                         string_list_insert(list, e->d_name);
30
31         closedir(dir);
32         return 0;
33 }
34
35 static int get_mode(const char *path, int *mode)
36 {
37         struct stat st;
38
39         if (!path || !strcmp(path, "/dev/null"))
40                 *mode = 0;
41 #ifdef _WIN32
42         else if (!strcasecmp(path, "nul"))
43                 *mode = 0;
44 #endif
45         else if (!strcmp(path, "-"))
46                 *mode = create_ce_mode(0666);
47         else if (lstat(path, &st))
48                 return error("Could not access '%s'", path);
49         else
50                 *mode = st.st_mode;
51         return 0;
52 }
53
54 static int queue_diff(struct diff_options *o,
55                 const char *name1, const char *name2)
56 {
57         int mode1 = 0, mode2 = 0;
58
59         if (get_mode(name1, &mode1) || get_mode(name2, &mode2))
60                 return -1;
61
62         if (mode1 && mode2 && S_ISDIR(mode1) != S_ISDIR(mode2))
63                 return error("file/directory conflict: %s, %s", name1, name2);
64
65         if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
66                 char buffer1[PATH_MAX], buffer2[PATH_MAX];
67                 struct string_list p1 = {NULL, 0, 0, 1}, p2 = {NULL, 0, 0, 1};
68                 int len1 = 0, len2 = 0, i1, i2, ret = 0;
69
70                 if (name1 && read_directory(name1, &p1))
71                         return -1;
72                 if (name2 && read_directory(name2, &p2)) {
73                         string_list_clear(&p1, 0);
74                         return -1;
75                 }
76
77                 if (name1) {
78                         len1 = strlen(name1);
79                         if (len1 > 0 && name1[len1 - 1] == '/')
80                                 len1--;
81                         memcpy(buffer1, name1, len1);
82                         buffer1[len1++] = '/';
83                 }
84
85                 if (name2) {
86                         len2 = strlen(name2);
87                         if (len2 > 0 && name2[len2 - 1] == '/')
88                                 len2--;
89                         memcpy(buffer2, name2, len2);
90                         buffer2[len2++] = '/';
91                 }
92
93                 for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
94                         const char *n1, *n2;
95                         int comp;
96
97                         if (i1 == p1.nr)
98                                 comp = 1;
99                         else if (i2 == p2.nr)
100                                 comp = -1;
101                         else
102                                 comp = strcmp(p1.items[i1].string,
103                                         p2.items[i2].string);
104
105                         if (comp > 0)
106                                 n1 = NULL;
107                         else {
108                                 n1 = buffer1;
109                                 strncpy(buffer1 + len1, p1.items[i1++].string,
110                                                 PATH_MAX - len1);
111                         }
112
113                         if (comp < 0)
114                                 n2 = NULL;
115                         else {
116                                 n2 = buffer2;
117                                 strncpy(buffer2 + len2, p2.items[i2++].string,
118                                                 PATH_MAX - len2);
119                         }
120
121                         ret = queue_diff(o, n1, n2);
122                 }
123                 string_list_clear(&p1, 0);
124                 string_list_clear(&p2, 0);
125
126                 return ret;
127         } else {
128                 struct diff_filespec *d1, *d2;
129
130                 if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
131                         unsigned tmp;
132                         const char *tmp_c;
133                         tmp = mode1; mode1 = mode2; mode2 = tmp;
134                         tmp_c = name1; name1 = name2; name2 = tmp_c;
135                 }
136
137                 if (!name1)
138                         name1 = "/dev/null";
139                 if (!name2)
140                         name2 = "/dev/null";
141                 d1 = alloc_filespec(name1);
142                 d2 = alloc_filespec(name2);
143                 fill_filespec(d1, null_sha1, mode1);
144                 fill_filespec(d2, null_sha1, mode2);
145
146                 diff_queue(&diff_queued_diff, d1, d2);
147                 return 0;
148         }
149 }
150
151 static int path_outside_repo(const char *path)
152 {
153         const char *work_tree;
154         size_t len;
155
156         if (!is_absolute_path(path))
157                 return 0;
158         work_tree = get_git_work_tree();
159         if (!work_tree)
160                 return 1;
161         len = strlen(work_tree);
162         if (strncmp(path, work_tree, len) ||
163             (path[len] != '\0' && path[len] != '/'))
164                 return 1;
165         return 0;
166 }
167
168 void diff_no_index(struct rev_info *revs,
169                    int argc, const char **argv,
170                    int nongit, const char *prefix)
171 {
172         int i;
173         int no_index = 0;
174         unsigned options = 0;
175
176         /* Were we asked to do --no-index explicitly? */
177         for (i = 1; i < argc; i++) {
178                 if (!strcmp(argv[i], "--")) {
179                         i++;
180                         break;
181                 }
182                 if (!strcmp(argv[i], "--no-index"))
183                         no_index = 1;
184                 if (argv[i][0] != '-')
185                         break;
186         }
187
188         if (!no_index && !nongit) {
189                 /*
190                  * Inside a git repository, without --no-index.  Only
191                  * when a path outside the repository is given,
192                  * e.g. "git diff /var/tmp/[12]", or "git diff
193                  * Makefile /var/tmp/Makefile", allow it to be used as
194                  * a colourful "diff" replacement.
195                  */
196                 if ((argc != i + 2) ||
197                     (!path_outside_repo(argv[i]) &&
198                      !path_outside_repo(argv[i+1])))
199                         return;
200         }
201         if (argc != i + 2)
202                 usagef("git diff %s <path> <path>",
203                        no_index ? "--no-index" : "[--no-index]");
204
205         diff_setup(&revs->diffopt);
206         for (i = 1; i < argc - 2; ) {
207                 int j;
208                 if (!strcmp(argv[i], "--no-index"))
209                         i++;
210                 else if (!strcmp(argv[i], "-q")) {
211                         options |= DIFF_SILENT_ON_REMOVED;
212                         i++;
213                 }
214                 else if (!strcmp(argv[i], "--"))
215                         i++;
216                 else {
217                         j = diff_opt_parse(&revs->diffopt, argv + i, argc - i);
218                         if (!j)
219                                 die("invalid diff option/value: %s", argv[i]);
220                         i += j;
221                 }
222         }
223
224         /*
225          * If the user asked for our exit code then don't start a
226          * pager or we would end up reporting its exit code instead.
227          */
228         if (!DIFF_OPT_TST(&revs->diffopt, EXIT_WITH_STATUS))
229                 setup_pager();
230
231         if (prefix) {
232                 int len = strlen(prefix);
233
234                 revs->diffopt.paths = xcalloc(2, sizeof(char *));
235                 for (i = 0; i < 2; i++) {
236                         const char *p = argv[argc - 2 + i];
237                         /*
238                          * stdin should be spelled as '-'; if you have
239                          * path that is '-', spell it as ./-.
240                          */
241                         p = (strcmp(p, "-")
242                              ? xstrdup(prefix_filename(prefix, len, p))
243                              : p);
244                         revs->diffopt.paths[i] = p;
245                 }
246         }
247         else
248                 revs->diffopt.paths = argv + argc - 2;
249         revs->diffopt.nr_paths = 2;
250         revs->diffopt.skip_stat_unmatch = 1;
251         if (!revs->diffopt.output_format)
252                 revs->diffopt.output_format = DIFF_FORMAT_PATCH;
253
254         DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);
255         DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
256
257         revs->max_count = -2;
258         if (diff_setup_done(&revs->diffopt) < 0)
259                 die("diff_setup_done failed");
260
261         if (queue_diff(&revs->diffopt, revs->diffopt.paths[0],
262                        revs->diffopt.paths[1]))
263                 exit(1);
264         diff_set_mnemonic_prefix(&revs->diffopt, "1/", "2/");
265         diffcore_std(&revs->diffopt);
266         diff_flush(&revs->diffopt);
267
268         /*
269          * The return code for --no-index imitates diff(1):
270          * 0 = no changes, 1 = changes, else error
271          */
272         exit(revs->diffopt.found_changes);
273 }