use SWAP macro
[git/git.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 #include "dir.h"
19
20 static int read_directory_contents(const char *path, struct string_list *list)
21 {
22 DIR *dir;
23 struct dirent *e;
24
25 if (!(dir = opendir(path)))
26 return error("Could not open directory %s", path);
27
28 while ((e = readdir(dir)))
29 if (!is_dot_or_dotdot(e->d_name))
30 string_list_insert(list, e->d_name);
31
32 closedir(dir);
33 return 0;
34 }
35
36 /*
37 * This should be "(standard input)" or something, but it will
38 * probably expose many more breakages in the way no-index code
39 * is bolted onto the diff callchain.
40 */
41 static const char file_from_standard_input[] = "-";
42
43 static int get_mode(const char *path, int *mode)
44 {
45 struct stat st;
46
47 if (!path || !strcmp(path, "/dev/null"))
48 *mode = 0;
49 #ifdef GIT_WINDOWS_NATIVE
50 else if (!strcasecmp(path, "nul"))
51 *mode = 0;
52 #endif
53 else if (path == file_from_standard_input)
54 *mode = create_ce_mode(0666);
55 else if (lstat(path, &st))
56 return error("Could not access '%s'", path);
57 else
58 *mode = st.st_mode;
59 return 0;
60 }
61
62 static int populate_from_stdin(struct diff_filespec *s)
63 {
64 struct strbuf buf = STRBUF_INIT;
65 size_t size = 0;
66
67 if (strbuf_read(&buf, 0, 0) < 0)
68 return error_errno("error while reading from stdin");
69
70 s->should_munmap = 0;
71 s->data = strbuf_detach(&buf, &size);
72 s->size = size;
73 s->should_free = 1;
74 s->is_stdin = 1;
75 return 0;
76 }
77
78 static struct diff_filespec *noindex_filespec(const char *name, int mode)
79 {
80 struct diff_filespec *s;
81
82 if (!name)
83 name = "/dev/null";
84 s = alloc_filespec(name);
85 fill_filespec(s, null_sha1, 0, mode);
86 if (name == file_from_standard_input)
87 populate_from_stdin(s);
88 return s;
89 }
90
91 static int queue_diff(struct diff_options *o,
92 const char *name1, const char *name2)
93 {
94 int mode1 = 0, mode2 = 0;
95
96 if (get_mode(name1, &mode1) || get_mode(name2, &mode2))
97 return -1;
98
99 if (mode1 && mode2 && S_ISDIR(mode1) != S_ISDIR(mode2)) {
100 struct diff_filespec *d1, *d2;
101
102 if (S_ISDIR(mode1)) {
103 /* 2 is file that is created */
104 d1 = noindex_filespec(NULL, 0);
105 d2 = noindex_filespec(name2, mode2);
106 name2 = NULL;
107 mode2 = 0;
108 } else {
109 /* 1 is file that is deleted */
110 d1 = noindex_filespec(name1, mode1);
111 d2 = noindex_filespec(NULL, 0);
112 name1 = NULL;
113 mode1 = 0;
114 }
115 /* emit that file */
116 diff_queue(&diff_queued_diff, d1, d2);
117
118 /* and then let the entire directory be created or deleted */
119 }
120
121 if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
122 struct strbuf buffer1 = STRBUF_INIT;
123 struct strbuf buffer2 = STRBUF_INIT;
124 struct string_list p1 = STRING_LIST_INIT_DUP;
125 struct string_list p2 = STRING_LIST_INIT_DUP;
126 int i1, i2, ret = 0;
127 size_t len1 = 0, len2 = 0;
128
129 if (name1 && read_directory_contents(name1, &p1))
130 return -1;
131 if (name2 && read_directory_contents(name2, &p2)) {
132 string_list_clear(&p1, 0);
133 return -1;
134 }
135
136 if (name1) {
137 strbuf_addstr(&buffer1, name1);
138 strbuf_complete(&buffer1, '/');
139 len1 = buffer1.len;
140 }
141
142 if (name2) {
143 strbuf_addstr(&buffer2, name2);
144 strbuf_complete(&buffer2, '/');
145 len2 = buffer2.len;
146 }
147
148 for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
149 const char *n1, *n2;
150 int comp;
151
152 strbuf_setlen(&buffer1, len1);
153 strbuf_setlen(&buffer2, len2);
154
155 if (i1 == p1.nr)
156 comp = 1;
157 else if (i2 == p2.nr)
158 comp = -1;
159 else
160 comp = strcmp(p1.items[i1].string, p2.items[i2].string);
161
162 if (comp > 0)
163 n1 = NULL;
164 else {
165 strbuf_addstr(&buffer1, p1.items[i1++].string);
166 n1 = buffer1.buf;
167 }
168
169 if (comp < 0)
170 n2 = NULL;
171 else {
172 strbuf_addstr(&buffer2, p2.items[i2++].string);
173 n2 = buffer2.buf;
174 }
175
176 ret = queue_diff(o, n1, n2);
177 }
178 string_list_clear(&p1, 0);
179 string_list_clear(&p2, 0);
180 strbuf_release(&buffer1);
181 strbuf_release(&buffer2);
182
183 return ret;
184 } else {
185 struct diff_filespec *d1, *d2;
186
187 if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
188 unsigned tmp;
189 tmp = mode1; mode1 = mode2; mode2 = tmp;
190 SWAP(name1, name2);
191 }
192
193 d1 = noindex_filespec(name1, mode1);
194 d2 = noindex_filespec(name2, mode2);
195 diff_queue(&diff_queued_diff, d1, d2);
196 return 0;
197 }
198 }
199
200 /* append basename of F to D */
201 static void append_basename(struct strbuf *path, const char *dir, const char *file)
202 {
203 const char *tail = strrchr(file, '/');
204
205 strbuf_addstr(path, dir);
206 while (path->len && path->buf[path->len - 1] == '/')
207 path->len--;
208 strbuf_addch(path, '/');
209 strbuf_addstr(path, tail ? tail + 1 : file);
210 }
211
212 /*
213 * DWIM "diff D F" into "diff D/F F" and "diff F D" into "diff F D/F"
214 * Note that we append the basename of F to D/, so "diff a/b/file D"
215 * becomes "diff a/b/file D/file", not "diff a/b/file D/a/b/file".
216 */
217 static void fixup_paths(const char **path, struct strbuf *replacement)
218 {
219 unsigned int isdir0, isdir1;
220
221 if (path[0] == file_from_standard_input ||
222 path[1] == file_from_standard_input)
223 return;
224 isdir0 = is_directory(path[0]);
225 isdir1 = is_directory(path[1]);
226 if (isdir0 == isdir1)
227 return;
228 if (isdir0) {
229 append_basename(replacement, path[0], path[1]);
230 path[0] = replacement->buf;
231 } else {
232 append_basename(replacement, path[1], path[0]);
233 path[1] = replacement->buf;
234 }
235 }
236
237 void diff_no_index(struct rev_info *revs,
238 int argc, const char **argv)
239 {
240 int i, prefixlen;
241 const char *paths[2];
242 struct strbuf replacement = STRBUF_INIT;
243 const char *prefix = revs->prefix;
244
245 diff_setup(&revs->diffopt);
246 for (i = 1; i < argc - 2; ) {
247 int j;
248 if (!strcmp(argv[i], "--no-index"))
249 i++;
250 else if (!strcmp(argv[i], "--"))
251 i++;
252 else {
253 j = diff_opt_parse(&revs->diffopt, argv + i, argc - i,
254 revs->prefix);
255 if (j <= 0)
256 die("invalid diff option/value: %s", argv[i]);
257 i += j;
258 }
259 }
260
261 prefixlen = prefix ? strlen(prefix) : 0;
262 for (i = 0; i < 2; i++) {
263 const char *p = argv[argc - 2 + i];
264 if (!strcmp(p, "-"))
265 /*
266 * stdin should be spelled as "-"; if you have
267 * path that is "-", spell it as "./-".
268 */
269 p = file_from_standard_input;
270 else if (prefixlen)
271 p = xstrdup(prefix_filename(prefix, prefixlen, p));
272 paths[i] = p;
273 }
274
275 fixup_paths(paths, &replacement);
276
277 revs->diffopt.skip_stat_unmatch = 1;
278 if (!revs->diffopt.output_format)
279 revs->diffopt.output_format = DIFF_FORMAT_PATCH;
280
281 DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
282
283 DIFF_OPT_SET(&revs->diffopt, RELATIVE_NAME);
284 revs->diffopt.prefix = prefix;
285
286 revs->max_count = -2;
287 diff_setup_done(&revs->diffopt);
288
289 setup_diff_pager(&revs->diffopt);
290 DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);
291
292 if (queue_diff(&revs->diffopt, paths[0], paths[1]))
293 exit(1);
294 diff_set_mnemonic_prefix(&revs->diffopt, "1/", "2/");
295 diffcore_std(&revs->diffopt);
296 diff_flush(&revs->diffopt);
297
298 strbuf_release(&replacement);
299
300 /*
301 * The return code for --no-index imitates diff(1):
302 * 0 = no changes, 1 = changes, else error
303 */
304 exit(diff_result_code(&revs->diffopt, 0));
305 }