Avoid segfault with 'git branch' when the HEAD is detached
[git/spearce.git] / diff-no-index.c
blob0dbd9dad8b100cdd4918571636ad3e9a1a0a2abf
1 /*
2 * "diff --no-index" support
3 * Copyright (c) 2007 by Johannes Schindelin
4 * Copyright (c) 2008 by Junio C Hamano
5 */
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"
19 static int read_directory(const char *path, struct string_list *list)
21 DIR *dir;
22 struct dirent *e;
24 if (!(dir = opendir(path)))
25 return error("Could not open directory %s", path);
27 while ((e = readdir(dir)))
28 if (strcmp(".", e->d_name) && strcmp("..", e->d_name))
29 string_list_insert(e->d_name, list);
31 closedir(dir);
32 return 0;
35 static int get_mode(const char *path, int *mode)
37 struct stat st;
39 if (!path || !strcmp(path, "/dev/null"))
40 *mode = 0;
41 else if (!strcmp(path, "-"))
42 *mode = create_ce_mode(0666);
43 else if (lstat(path, &st))
44 return error("Could not access '%s'", path);
45 else
46 *mode = st.st_mode;
47 return 0;
50 static int queue_diff(struct diff_options *o,
51 const char *name1, const char *name2)
53 int mode1 = 0, mode2 = 0;
55 if (get_mode(name1, &mode1) || get_mode(name2, &mode2))
56 return -1;
58 if (mode1 && mode2 && S_ISDIR(mode1) != S_ISDIR(mode2))
59 return error("file/directory conflict: %s, %s", name1, name2);
61 if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
62 char buffer1[PATH_MAX], buffer2[PATH_MAX];
63 struct string_list p1 = {NULL, 0, 0, 1}, p2 = {NULL, 0, 0, 1};
64 int len1 = 0, len2 = 0, i1, i2, ret = 0;
66 if (name1 && read_directory(name1, &p1))
67 return -1;
68 if (name2 && read_directory(name2, &p2)) {
69 string_list_clear(&p1, 0);
70 return -1;
73 if (name1) {
74 len1 = strlen(name1);
75 if (len1 > 0 && name1[len1 - 1] == '/')
76 len1--;
77 memcpy(buffer1, name1, len1);
78 buffer1[len1++] = '/';
81 if (name2) {
82 len2 = strlen(name2);
83 if (len2 > 0 && name2[len2 - 1] == '/')
84 len2--;
85 memcpy(buffer2, name2, len2);
86 buffer2[len2++] = '/';
89 for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
90 const char *n1, *n2;
91 int comp;
93 if (i1 == p1.nr)
94 comp = 1;
95 else if (i2 == p2.nr)
96 comp = -1;
97 else
98 comp = strcmp(p1.items[i1].string,
99 p2.items[i2].string);
101 if (comp > 0)
102 n1 = NULL;
103 else {
104 n1 = buffer1;
105 strncpy(buffer1 + len1, p1.items[i1++].string,
106 PATH_MAX - len1);
109 if (comp < 0)
110 n2 = NULL;
111 else {
112 n2 = buffer2;
113 strncpy(buffer2 + len2, p2.items[i2++].string,
114 PATH_MAX - len2);
117 ret = queue_diff(o, n1, n2);
119 string_list_clear(&p1, 0);
120 string_list_clear(&p2, 0);
122 return ret;
123 } else {
124 struct diff_filespec *d1, *d2;
126 if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
127 unsigned tmp;
128 const char *tmp_c;
129 tmp = mode1; mode1 = mode2; mode2 = tmp;
130 tmp_c = name1; name1 = name2; name2 = tmp_c;
133 if (!name1)
134 name1 = "/dev/null";
135 if (!name2)
136 name2 = "/dev/null";
137 d1 = alloc_filespec(name1);
138 d2 = alloc_filespec(name2);
139 fill_filespec(d1, null_sha1, mode1);
140 fill_filespec(d2, null_sha1, mode2);
142 diff_queue(&diff_queued_diff, d1, d2);
143 return 0;
147 static int path_outside_repo(const char *path)
150 * We have already done setup_git_directory_gently() so we
151 * know we are inside a git work tree already.
153 const char *work_tree;
154 size_t len;
156 if (!is_absolute_path(path))
157 return 0;
158 work_tree = get_git_work_tree();
159 len = strlen(work_tree);
160 if (strncmp(path, work_tree, len) ||
161 (path[len] != '\0' && path[len] != '/'))
162 return 1;
163 return 0;
166 void diff_no_index(struct rev_info *revs,
167 int argc, const char **argv,
168 int nongit, const char *prefix)
170 int i;
171 int no_index = 0;
172 unsigned options = 0;
174 /* Were we asked to do --no-index explicitly? */
175 for (i = 1; i < argc; i++) {
176 if (!strcmp(argv[i], "--")) {
177 i++;
178 break;
180 if (!strcmp(argv[i], "--no-index"))
181 no_index = 1;
182 if (argv[i][0] != '-')
183 break;
186 if (!no_index && !nongit) {
188 * Inside a git repository, without --no-index. Only
189 * when a path outside the repository is given,
190 * e.g. "git diff /var/tmp/[12]", or "git diff
191 * Makefile /var/tmp/Makefile", allow it to be used as
192 * a colourful "diff" replacement.
194 if ((argc != i + 2) ||
195 (!path_outside_repo(argv[i]) &&
196 !path_outside_repo(argv[i+1])))
197 return;
199 if (argc != i + 2)
200 die("git diff %s takes two paths",
201 no_index ? "--no-index" : "[--no-index]");
203 diff_setup(&revs->diffopt);
204 if (!revs->diffopt.output_format)
205 revs->diffopt.output_format = DIFF_FORMAT_PATCH;
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++;
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;
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.
228 if (!DIFF_OPT_TST(&revs->diffopt, EXIT_WITH_STATUS))
229 setup_pager();
231 if (prefix) {
232 int len = strlen(prefix);
234 revs->diffopt.paths = xcalloc(2, sizeof(char*));
235 for (i = 0; i < 2; i++) {
236 const char *p = argv[argc - 2 + i];
238 * stdin should be spelled as '-'; if you have
239 * path that is '-', spell it as ./-.
241 p = (strcmp(p, "-")
242 ? xstrdup(prefix_filename(prefix, len, p))
243 : p);
244 revs->diffopt.paths[i] = p;
247 else
248 revs->diffopt.paths = argv + argc - 2;
249 revs->diffopt.nr_paths = 2;
251 DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);
252 DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
254 revs->max_count = -2;
255 if (diff_setup_done(&revs->diffopt) < 0)
256 die("diff_setup_done failed");
258 if (queue_diff(&revs->diffopt, revs->diffopt.paths[0],
259 revs->diffopt.paths[1]))
260 exit(1);
261 diff_set_mnemonic_prefix(&revs->diffopt, "1/", "2/");
262 diffcore_std(&revs->diffopt);
263 diff_flush(&revs->diffopt);
266 * The return code for --no-index imitates diff(1):
267 * 0 = no changes, 1 = changes, else error
269 exit(revs->diffopt.found_changes);