git: use COPY_ARRAY and MOVE_ARRAY in handle_alias()
[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 "parse-options.h"
18 #include "string-list.h"
19 #include "dir.h"
20
21 static int read_directory_contents(const char *path, struct string_list *list)
22 {
23 DIR *dir;
24 struct dirent *e;
25
26 if (!(dir = opendir(path)))
27 return error("Could not open directory %s", path);
28
29 while ((e = readdir(dir)))
30 if (!is_dot_or_dotdot(e->d_name))
31 string_list_insert(list, e->d_name);
32
33 closedir(dir);
34 return 0;
35 }
36
37 /*
38 * This should be "(standard input)" or something, but it will
39 * probably expose many more breakages in the way no-index code
40 * is bolted onto the diff callchain.
41 */
42 static const char file_from_standard_input[] = "-";
43
44 static int get_mode(const char *path, int *mode)
45 {
46 struct stat st;
47
48 if (!path || !strcmp(path, "/dev/null"))
49 *mode = 0;
50 #ifdef GIT_WINDOWS_NATIVE
51 else if (!strcasecmp(path, "nul"))
52 *mode = 0;
53 #endif
54 else if (path == file_from_standard_input)
55 *mode = create_ce_mode(0666);
56 else if (lstat(path, &st))
57 return error("Could not access '%s'", path);
58 else
59 *mode = st.st_mode;
60 return 0;
61 }
62
63 static int populate_from_stdin(struct diff_filespec *s)
64 {
65 struct strbuf buf = STRBUF_INIT;
66 size_t size = 0;
67
68 if (strbuf_read(&buf, 0, 0) < 0)
69 return error_errno("error while reading from stdin");
70
71 s->should_munmap = 0;
72 s->data = strbuf_detach(&buf, &size);
73 s->size = size;
74 s->should_free = 1;
75 s->is_stdin = 1;
76 return 0;
77 }
78
79 static struct diff_filespec *noindex_filespec(const char *name, int mode)
80 {
81 struct diff_filespec *s;
82
83 if (!name)
84 name = "/dev/null";
85 s = alloc_filespec(name);
86 fill_filespec(s, &null_oid, 0, mode);
87 if (name == file_from_standard_input)
88 populate_from_stdin(s);
89 return s;
90 }
91
92 static int queue_diff(struct diff_options *o,
93 const char *name1, const char *name2)
94 {
95 int mode1 = 0, mode2 = 0;
96
97 if (get_mode(name1, &mode1) || get_mode(name2, &mode2))
98 return -1;
99
100 if (mode1 && mode2 && S_ISDIR(mode1) != S_ISDIR(mode2)) {
101 struct diff_filespec *d1, *d2;
102
103 if (S_ISDIR(mode1)) {
104 /* 2 is file that is created */
105 d1 = noindex_filespec(NULL, 0);
106 d2 = noindex_filespec(name2, mode2);
107 name2 = NULL;
108 mode2 = 0;
109 } else {
110 /* 1 is file that is deleted */
111 d1 = noindex_filespec(name1, mode1);
112 d2 = noindex_filespec(NULL, 0);
113 name1 = NULL;
114 mode1 = 0;
115 }
116 /* emit that file */
117 diff_queue(&diff_queued_diff, d1, d2);
118
119 /* and then let the entire directory be created or deleted */
120 }
121
122 if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
123 struct strbuf buffer1 = STRBUF_INIT;
124 struct strbuf buffer2 = STRBUF_INIT;
125 struct string_list p1 = STRING_LIST_INIT_DUP;
126 struct string_list p2 = STRING_LIST_INIT_DUP;
127 int i1, i2, ret = 0;
128 size_t len1 = 0, len2 = 0;
129
130 if (name1 && read_directory_contents(name1, &p1))
131 return -1;
132 if (name2 && read_directory_contents(name2, &p2)) {
133 string_list_clear(&p1, 0);
134 return -1;
135 }
136
137 if (name1) {
138 strbuf_addstr(&buffer1, name1);
139 strbuf_complete(&buffer1, '/');
140 len1 = buffer1.len;
141 }
142
143 if (name2) {
144 strbuf_addstr(&buffer2, name2);
145 strbuf_complete(&buffer2, '/');
146 len2 = buffer2.len;
147 }
148
149 for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
150 const char *n1, *n2;
151 int comp;
152
153 strbuf_setlen(&buffer1, len1);
154 strbuf_setlen(&buffer2, len2);
155
156 if (i1 == p1.nr)
157 comp = 1;
158 else if (i2 == p2.nr)
159 comp = -1;
160 else
161 comp = strcmp(p1.items[i1].string, p2.items[i2].string);
162
163 if (comp > 0)
164 n1 = NULL;
165 else {
166 strbuf_addstr(&buffer1, p1.items[i1++].string);
167 n1 = buffer1.buf;
168 }
169
170 if (comp < 0)
171 n2 = NULL;
172 else {
173 strbuf_addstr(&buffer2, p2.items[i2++].string);
174 n2 = buffer2.buf;
175 }
176
177 ret = queue_diff(o, n1, n2);
178 }
179 string_list_clear(&p1, 0);
180 string_list_clear(&p2, 0);
181 strbuf_release(&buffer1);
182 strbuf_release(&buffer2);
183
184 return ret;
185 } else {
186 struct diff_filespec *d1, *d2;
187
188 if (o->flags.reverse_diff) {
189 SWAP(mode1, mode2);
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 static const char * const diff_no_index_usage[] = {
238 N_("git diff --no-index [<options>] <path> <path>"),
239 NULL
240 };
241
242 int diff_no_index(struct rev_info *revs,
243 int implicit_no_index,
244 int argc, const char **argv)
245 {
246 int i, no_index;
247 const char *paths[2];
248 struct strbuf replacement = STRBUF_INIT;
249 const char *prefix = revs->prefix;
250 struct option no_index_options[] = {
251 OPT_BOOL_F(0, "no-index", &no_index, "",
252 PARSE_OPT_NONEG | PARSE_OPT_HIDDEN),
253 OPT_END(),
254 };
255 struct option *options;
256
257 options = parse_options_concat(no_index_options,
258 revs->diffopt.parseopts);
259 argc = parse_options(argc, argv, revs->prefix, options,
260 diff_no_index_usage, 0);
261 if (argc != 2) {
262 if (implicit_no_index)
263 warning(_("Not a git repository. Use --no-index to "
264 "compare two paths outside a working tree"));
265 usage_with_options(diff_no_index_usage, options);
266 }
267 FREE_AND_NULL(options);
268 for (i = 0; i < 2; i++) {
269 const char *p = argv[argc - 2 + i];
270 if (!strcmp(p, "-"))
271 /*
272 * stdin should be spelled as "-"; if you have
273 * path that is "-", spell it as "./-".
274 */
275 p = file_from_standard_input;
276 else if (prefix)
277 p = prefix_filename(prefix, p);
278 paths[i] = p;
279 }
280
281 fixup_paths(paths, &replacement);
282
283 revs->diffopt.skip_stat_unmatch = 1;
284 if (!revs->diffopt.output_format)
285 revs->diffopt.output_format = DIFF_FORMAT_PATCH;
286
287 revs->diffopt.flags.no_index = 1;
288
289 revs->diffopt.flags.relative_name = 1;
290 revs->diffopt.prefix = prefix;
291
292 revs->max_count = -2;
293 diff_setup_done(&revs->diffopt);
294
295 setup_diff_pager(&revs->diffopt);
296 revs->diffopt.flags.exit_with_status = 1;
297
298 if (queue_diff(&revs->diffopt, paths[0], paths[1]))
299 return 1;
300 diff_set_mnemonic_prefix(&revs->diffopt, "1/", "2/");
301 diffcore_std(&revs->diffopt);
302 diff_flush(&revs->diffopt);
303
304 strbuf_release(&replacement);
305
306 /*
307 * The return code for --no-index imitates diff(1):
308 * 0 = no changes, 1 = changes, else error
309 */
310 return diff_result_code(&revs->diffopt, 0);
311 }