reset [--mixed]: only write index file once
[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 /*
36  * This should be "(standard input)" or something, but it will
37  * probably expose many more breakages in the way no-index code
38  * is bolted onto the diff callchain.
39  */
40 static const char file_from_standard_input[] = "-";
41
42 static int get_mode(const char *path, int *mode)
43 {
44         struct stat st;
45
46         if (!path || !strcmp(path, "/dev/null"))
47                 *mode = 0;
48 #ifdef _WIN32
49         else if (!strcasecmp(path, "nul"))
50                 *mode = 0;
51 #endif
52         else if (path == file_from_standard_input)
53                 *mode = create_ce_mode(0666);
54         else if (lstat(path, &st))
55                 return error("Could not access '%s'", path);
56         else
57                 *mode = st.st_mode;
58         return 0;
59 }
60
61 static int populate_from_stdin(struct diff_filespec *s)
62 {
63         struct strbuf buf = STRBUF_INIT;
64         size_t size = 0;
65
66         if (strbuf_read(&buf, 0, 0) < 0)
67                 return error("error while reading from stdin %s",
68                                      strerror(errno));
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                 return error("file/directory conflict: %s, %s", name1, name2);
101
102         if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
103                 struct strbuf buffer1 = STRBUF_INIT;
104                 struct strbuf buffer2 = STRBUF_INIT;
105                 struct string_list p1 = STRING_LIST_INIT_DUP;
106                 struct string_list p2 = STRING_LIST_INIT_DUP;
107                 int i1, i2, ret = 0;
108                 size_t len1 = 0, len2 = 0;
109
110                 if (name1 && read_directory(name1, &p1))
111                         return -1;
112                 if (name2 && read_directory(name2, &p2)) {
113                         string_list_clear(&p1, 0);
114                         return -1;
115                 }
116
117                 if (name1) {
118                         strbuf_addstr(&buffer1, name1);
119                         if (buffer1.len && buffer1.buf[buffer1.len - 1] != '/')
120                                 strbuf_addch(&buffer1, '/');
121                         len1 = buffer1.len;
122                 }
123
124                 if (name2) {
125                         strbuf_addstr(&buffer2, name2);
126                         if (buffer2.len && buffer2.buf[buffer2.len - 1] != '/')
127                                 strbuf_addch(&buffer2, '/');
128                         len2 = buffer2.len;
129                 }
130
131                 for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
132                         const char *n1, *n2;
133                         int comp;
134
135                         strbuf_setlen(&buffer1, len1);
136                         strbuf_setlen(&buffer2, len2);
137
138                         if (i1 == p1.nr)
139                                 comp = 1;
140                         else if (i2 == p2.nr)
141                                 comp = -1;
142                         else
143                                 comp = strcmp(p1.items[i1].string, p2.items[i2].string);
144
145                         if (comp > 0)
146                                 n1 = NULL;
147                         else {
148                                 strbuf_addstr(&buffer1, p1.items[i1++].string);
149                                 n1 = buffer1.buf;
150                         }
151
152                         if (comp < 0)
153                                 n2 = NULL;
154                         else {
155                                 strbuf_addstr(&buffer2, p2.items[i2++].string);
156                                 n2 = buffer2.buf;
157                         }
158
159                         ret = queue_diff(o, n1, n2);
160                 }
161                 string_list_clear(&p1, 0);
162                 string_list_clear(&p2, 0);
163                 strbuf_release(&buffer1);
164                 strbuf_release(&buffer2);
165
166                 return ret;
167         } else {
168                 struct diff_filespec *d1, *d2;
169
170                 if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
171                         unsigned tmp;
172                         const char *tmp_c;
173                         tmp = mode1; mode1 = mode2; mode2 = tmp;
174                         tmp_c = name1; name1 = name2; name2 = tmp_c;
175                 }
176
177                 d1 = noindex_filespec(name1, mode1);
178                 d2 = noindex_filespec(name2, mode2);
179                 diff_queue(&diff_queued_diff, d1, d2);
180                 return 0;
181         }
182 }
183
184 void diff_no_index(struct rev_info *revs,
185                    int argc, const char **argv,
186                    int nongit, const char *prefix)
187 {
188         int i, prefixlen;
189         int no_index = 0;
190         unsigned options = 0;
191         const char *paths[2];
192
193         /* Were we asked to do --no-index explicitly? */
194         for (i = 1; i < argc; i++) {
195                 if (!strcmp(argv[i], "--")) {
196                         i++;
197                         break;
198                 }
199                 if (!strcmp(argv[i], "--no-index"))
200                         no_index = 1;
201                 if (argv[i][0] != '-')
202                         break;
203         }
204
205         if (!no_index && !nongit) {
206                 /*
207                  * Inside a git repository, without --no-index.  Only
208                  * when a path outside the repository is given,
209                  * e.g. "git diff /var/tmp/[12]", or "git diff
210                  * Makefile /var/tmp/Makefile", allow it to be used as
211                  * a colourful "diff" replacement.
212                  */
213                 if ((argc != i + 2) ||
214                     (path_inside_repo(prefix, argv[i]) &&
215                      path_inside_repo(prefix, argv[i+1])))
216                         return;
217         }
218         if (argc != i + 2)
219                 usagef("git diff %s <path> <path>",
220                        no_index ? "--no-index" : "[--no-index]");
221
222         diff_setup(&revs->diffopt);
223         for (i = 1; i < argc - 2; ) {
224                 int j;
225                 if (!strcmp(argv[i], "--no-index"))
226                         i++;
227                 else if (!strcmp(argv[i], "-q")) {
228                         options |= DIFF_SILENT_ON_REMOVED;
229                         i++;
230                 }
231                 else if (!strcmp(argv[i], "--"))
232                         i++;
233                 else {
234                         j = diff_opt_parse(&revs->diffopt, argv + i, argc - i);
235                         if (!j)
236                                 die("invalid diff option/value: %s", argv[i]);
237                         i += j;
238                 }
239         }
240
241         prefixlen = prefix ? strlen(prefix) : 0;
242         for (i = 0; i < 2; i++) {
243                 const char *p = argv[argc - 2 + i];
244                 if (!strcmp(p, "-"))
245                         /*
246                          * stdin should be spelled as "-"; if you have
247                          * path that is "-", spell it as "./-".
248                          */
249                         p = file_from_standard_input;
250                 else if (prefixlen)
251                         p = xstrdup(prefix_filename(prefix, prefixlen, p));
252                 paths[i] = p;
253         }
254         revs->diffopt.skip_stat_unmatch = 1;
255         if (!revs->diffopt.output_format)
256                 revs->diffopt.output_format = DIFF_FORMAT_PATCH;
257
258         DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
259
260         revs->max_count = -2;
261         diff_setup_done(&revs->diffopt);
262
263         setup_diff_pager(&revs->diffopt);
264         DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);
265
266         if (queue_diff(&revs->diffopt, paths[0], paths[1]))
267                 exit(1);
268         diff_set_mnemonic_prefix(&revs->diffopt, "1/", "2/");
269         diffcore_std(&revs->diffopt);
270         diff_flush(&revs->diffopt);
271
272         /*
273          * The return code for --no-index imitates diff(1):
274          * 0 = no changes, 1 = changes, else error
275          */
276         exit(diff_result_code(&revs->diffopt, 0));
277 }