Commit | Line | Data |
---|---|---|
525ab639 JH |
1 | /* |
2 | * Low level 3-way in-core file merge. | |
3 | * | |
4 | * Copyright (c) 2007 Junio C Hamano | |
5 | */ | |
6 | ||
7 | #include "cache.h" | |
8 | #include "attr.h" | |
9 | #include "xdiff-interface.h" | |
10 | #include "run-command.h" | |
525ab639 JH |
11 | #include "ll-merge.h" |
12 | ||
13 | struct ll_merge_driver; | |
14 | ||
15 | typedef int (*ll_merge_fn)(const struct ll_merge_driver *, | |
16 | mmbuffer_t *result, | |
17 | const char *path, | |
f01de62e | 18 | mmfile_t *orig, const char *orig_name, |
525ab639 JH |
19 | mmfile_t *src1, const char *name1, |
20 | mmfile_t *src2, const char *name2, | |
712516bc | 21 | const struct ll_merge_options *opts, |
23a64c9e | 22 | int marker_size); |
525ab639 JH |
23 | |
24 | struct ll_merge_driver { | |
25 | const char *name; | |
26 | const char *description; | |
27 | ll_merge_fn fn; | |
28 | const char *recursive; | |
29 | struct ll_merge_driver *next; | |
30 | char *cmdline; | |
31 | }; | |
32 | ||
33 | /* | |
34 | * Built-in low-levels | |
35 | */ | |
36 | static int ll_binary_merge(const struct ll_merge_driver *drv_unused, | |
37 | mmbuffer_t *result, | |
38 | const char *path_unused, | |
f01de62e | 39 | mmfile_t *orig, const char *orig_name, |
525ab639 JH |
40 | mmfile_t *src1, const char *name1, |
41 | mmfile_t *src2, const char *name2, | |
712516bc JN |
42 | const struct ll_merge_options *opts, |
43 | int marker_size) | |
525ab639 | 44 | { |
712516bc JN |
45 | mmfile_t *stolen; |
46 | assert(opts); | |
47 | ||
525ab639 | 48 | /* |
a944af1d | 49 | * The tentative merge result is the or common ancestor for an internal merge. |
525ab639 | 50 | */ |
a944af1d JH |
51 | if (opts->virtual_ancestor) { |
52 | stolen = orig; | |
53 | } else { | |
54 | switch (opts->variant) { | |
55 | default: | |
56 | case XDL_MERGE_FAVOR_OURS: | |
57 | stolen = src1; | |
58 | break; | |
59 | case XDL_MERGE_FAVOR_THEIRS: | |
60 | stolen = src2; | |
61 | break; | |
62 | } | |
63 | } | |
525ab639 JH |
64 | |
65 | result->ptr = stolen->ptr; | |
66 | result->size = stolen->size; | |
67 | stolen->ptr = NULL; | |
a944af1d JH |
68 | |
69 | /* | |
70 | * With -Xtheirs or -Xours, we have cleanly merged; | |
71 | * otherwise we got a conflict. | |
72 | */ | |
73 | return (opts->variant ? 0 : 1); | |
525ab639 JH |
74 | } |
75 | ||
76 | static int ll_xdl_merge(const struct ll_merge_driver *drv_unused, | |
77 | mmbuffer_t *result, | |
606475f3 | 78 | const char *path, |
f01de62e | 79 | mmfile_t *orig, const char *orig_name, |
525ab639 JH |
80 | mmfile_t *src1, const char *name1, |
81 | mmfile_t *src2, const char *name2, | |
712516bc JN |
82 | const struct ll_merge_options *opts, |
83 | int marker_size) | |
525ab639 | 84 | { |
00f8f97d | 85 | xmparam_t xmp; |
712516bc | 86 | assert(opts); |
525ab639 JH |
87 | |
88 | if (buffer_is_binary(orig->ptr, orig->size) || | |
89 | buffer_is_binary(src1->ptr, src1->size) || | |
90 | buffer_is_binary(src2->ptr, src2->size)) { | |
606475f3 MR |
91 | warning("Cannot merge binary files: %s (%s vs. %s)\n", |
92 | path, name1, name2); | |
525ab639 | 93 | return ll_binary_merge(drv_unused, result, |
606475f3 | 94 | path, |
f01de62e JN |
95 | orig, orig_name, |
96 | src1, name1, | |
525ab639 | 97 | src2, name2, |
712516bc | 98 | opts, marker_size); |
525ab639 JH |
99 | } |
100 | ||
00f8f97d | 101 | memset(&xmp, 0, sizeof(xmp)); |
560119b9 | 102 | xmp.level = XDL_MERGE_ZEALOUS; |
712516bc | 103 | xmp.favor = opts->variant; |
58a1ece4 | 104 | xmp.xpp.flags = opts->xdl_opts; |
c236bcd0 | 105 | if (git_xmerge_style >= 0) |
560119b9 | 106 | xmp.style = git_xmerge_style; |
23a64c9e JH |
107 | if (marker_size > 0) |
108 | xmp.marker_size = marker_size; | |
f01de62e | 109 | xmp.ancestor = orig_name; |
a4b5e91c JN |
110 | xmp.file1 = name1; |
111 | xmp.file2 = name2; | |
112 | return xdl_merge(orig, src1, src2, &xmp, result); | |
525ab639 JH |
113 | } |
114 | ||
115 | static int ll_union_merge(const struct ll_merge_driver *drv_unused, | |
116 | mmbuffer_t *result, | |
117 | const char *path_unused, | |
f01de62e | 118 | mmfile_t *orig, const char *orig_name, |
525ab639 JH |
119 | mmfile_t *src1, const char *name1, |
120 | mmfile_t *src2, const char *name2, | |
712516bc JN |
121 | const struct ll_merge_options *opts, |
122 | int marker_size) | |
525ab639 | 123 | { |
cd1d61c4 | 124 | /* Use union favor */ |
712516bc JN |
125 | struct ll_merge_options o; |
126 | assert(opts); | |
127 | o = *opts; | |
128 | o.variant = XDL_MERGE_FAVOR_UNION; | |
cd1d61c4 | 129 | return ll_xdl_merge(drv_unused, result, path_unused, |
f01de62e | 130 | orig, NULL, src1, NULL, src2, NULL, |
712516bc | 131 | &o, marker_size); |
525ab639 JH |
132 | } |
133 | ||
134 | #define LL_BINARY_MERGE 0 | |
135 | #define LL_TEXT_MERGE 1 | |
136 | #define LL_UNION_MERGE 2 | |
137 | static struct ll_merge_driver ll_merge_drv[] = { | |
138 | { "binary", "built-in binary merge", ll_binary_merge }, | |
139 | { "text", "built-in 3-way text merge", ll_xdl_merge }, | |
140 | { "union", "built-in union merge", ll_union_merge }, | |
141 | }; | |
142 | ||
143 | static void create_temp(mmfile_t *src, char *path) | |
144 | { | |
145 | int fd; | |
146 | ||
147 | strcpy(path, ".merge_file_XXXXXX"); | |
148 | fd = xmkstemp(path); | |
149 | if (write_in_full(fd, src->ptr, src->size) != src->size) | |
0721c314 | 150 | die_errno("unable to write temp-file"); |
525ab639 JH |
151 | close(fd); |
152 | } | |
153 | ||
154 | /* | |
155 | * User defined low-level merge driver support. | |
156 | */ | |
157 | static int ll_ext_merge(const struct ll_merge_driver *fn, | |
158 | mmbuffer_t *result, | |
159 | const char *path, | |
f01de62e | 160 | mmfile_t *orig, const char *orig_name, |
525ab639 JH |
161 | mmfile_t *src1, const char *name1, |
162 | mmfile_t *src2, const char *name2, | |
712516bc JN |
163 | const struct ll_merge_options *opts, |
164 | int marker_size) | |
525ab639 | 165 | { |
23a64c9e | 166 | char temp[4][50]; |
ced621b2 | 167 | struct strbuf cmd = STRBUF_INIT; |
66dbfd55 | 168 | struct strbuf_expand_dict_entry dict[5]; |
ac0ba18d | 169 | const char *args[] = { NULL, NULL }; |
525ab639 JH |
170 | int status, fd, i; |
171 | struct stat st; | |
712516bc | 172 | assert(opts); |
525ab639 | 173 | |
66dbfd55 GV |
174 | dict[0].placeholder = "O"; dict[0].value = temp[0]; |
175 | dict[1].placeholder = "A"; dict[1].value = temp[1]; | |
176 | dict[2].placeholder = "B"; dict[2].value = temp[2]; | |
177 | dict[3].placeholder = "L"; dict[3].value = temp[3]; | |
178 | dict[4].placeholder = NULL; dict[4].value = NULL; | |
179 | ||
525ab639 JH |
180 | if (fn->cmdline == NULL) |
181 | die("custom merge driver %s lacks command line.", fn->name); | |
182 | ||
183 | result->ptr = NULL; | |
184 | result->size = 0; | |
185 | create_temp(orig, temp[0]); | |
186 | create_temp(src1, temp[1]); | |
187 | create_temp(src2, temp[2]); | |
23a64c9e | 188 | sprintf(temp[3], "%d", marker_size); |
525ab639 | 189 | |
ced621b2 | 190 | strbuf_expand(&cmd, fn->cmdline, strbuf_expand_dict_cb, &dict); |
525ab639 | 191 | |
ac0ba18d JK |
192 | args[0] = cmd.buf; |
193 | status = run_command_v_opt(args, RUN_USING_SHELL); | |
525ab639 JH |
194 | fd = open(temp[1], O_RDONLY); |
195 | if (fd < 0) | |
196 | goto bad; | |
197 | if (fstat(fd, &st)) | |
198 | goto close_bad; | |
199 | result->size = st.st_size; | |
200 | result->ptr = xmalloc(result->size + 1); | |
201 | if (read_in_full(fd, result->ptr, result->size) != result->size) { | |
202 | free(result->ptr); | |
203 | result->ptr = NULL; | |
204 | result->size = 0; | |
205 | } | |
206 | close_bad: | |
207 | close(fd); | |
208 | bad: | |
209 | for (i = 0; i < 3; i++) | |
691f1a28 | 210 | unlink_or_warn(temp[i]); |
ced621b2 | 211 | strbuf_release(&cmd); |
525ab639 JH |
212 | return status; |
213 | } | |
214 | ||
215 | /* | |
216 | * merge.default and merge.driver configuration items | |
217 | */ | |
218 | static struct ll_merge_driver *ll_user_merge, **ll_user_merge_tail; | |
219 | static const char *default_ll_merge; | |
220 | ||
ef90d6d4 | 221 | static int read_merge_config(const char *var, const char *value, void *cb) |
525ab639 JH |
222 | { |
223 | struct ll_merge_driver *fn; | |
224 | const char *ep, *name; | |
225 | int namelen; | |
226 | ||
227 | if (!strcmp(var, "merge.default")) { | |
228 | if (value) | |
90dce515 | 229 | default_ll_merge = xstrdup(value); |
525ab639 JH |
230 | return 0; |
231 | } | |
232 | ||
233 | /* | |
234 | * We are not interested in anything but "merge.<name>.variable"; | |
235 | * especially, we do not want to look at variables such as | |
236 | * "merge.summary", "merge.tool", and "merge.verbosity". | |
237 | */ | |
238 | if (prefixcmp(var, "merge.") || (ep = strrchr(var, '.')) == var + 5) | |
239 | return 0; | |
240 | ||
241 | /* | |
242 | * Find existing one as we might be processing merge.<name>.var2 | |
243 | * after seeing merge.<name>.var1. | |
244 | */ | |
245 | name = var + 6; | |
246 | namelen = ep - name; | |
247 | for (fn = ll_user_merge; fn; fn = fn->next) | |
248 | if (!strncmp(fn->name, name, namelen) && !fn->name[namelen]) | |
249 | break; | |
250 | if (!fn) { | |
251 | fn = xcalloc(1, sizeof(struct ll_merge_driver)); | |
252 | fn->name = xmemdupz(name, namelen); | |
253 | fn->fn = ll_ext_merge; | |
254 | *ll_user_merge_tail = fn; | |
255 | ll_user_merge_tail = &(fn->next); | |
256 | } | |
257 | ||
258 | ep++; | |
259 | ||
260 | if (!strcmp("name", ep)) { | |
261 | if (!value) | |
262 | return error("%s: lacks value", var); | |
90dce515 | 263 | fn->description = xstrdup(value); |
525ab639 JH |
264 | return 0; |
265 | } | |
266 | ||
267 | if (!strcmp("driver", ep)) { | |
268 | if (!value) | |
269 | return error("%s: lacks value", var); | |
270 | /* | |
271 | * merge.<name>.driver specifies the command line: | |
272 | * | |
273 | * command-line | |
274 | * | |
275 | * The command-line will be interpolated with the following | |
276 | * tokens and is given to the shell: | |
277 | * | |
278 | * %O - temporary file name for the merge base. | |
279 | * %A - temporary file name for our version. | |
280 | * %B - temporary file name for the other branches' version. | |
23a64c9e | 281 | * %L - conflict marker length |
525ab639 JH |
282 | * |
283 | * The external merge driver should write the results in the | |
284 | * file named by %A, and signal that it has done with zero exit | |
285 | * status. | |
286 | */ | |
90dce515 | 287 | fn->cmdline = xstrdup(value); |
525ab639 JH |
288 | return 0; |
289 | } | |
290 | ||
291 | if (!strcmp("recursive", ep)) { | |
292 | if (!value) | |
293 | return error("%s: lacks value", var); | |
90dce515 | 294 | fn->recursive = xstrdup(value); |
525ab639 JH |
295 | return 0; |
296 | } | |
297 | ||
298 | return 0; | |
299 | } | |
300 | ||
301 | static void initialize_ll_merge(void) | |
302 | { | |
303 | if (ll_user_merge_tail) | |
304 | return; | |
305 | ll_user_merge_tail = &ll_user_merge; | |
ef90d6d4 | 306 | git_config(read_merge_config, NULL); |
525ab639 JH |
307 | } |
308 | ||
309 | static const struct ll_merge_driver *find_ll_merge_driver(const char *merge_attr) | |
310 | { | |
311 | struct ll_merge_driver *fn; | |
312 | const char *name; | |
313 | int i; | |
314 | ||
315 | initialize_ll_merge(); | |
316 | ||
317 | if (ATTR_TRUE(merge_attr)) | |
318 | return &ll_merge_drv[LL_TEXT_MERGE]; | |
319 | else if (ATTR_FALSE(merge_attr)) | |
320 | return &ll_merge_drv[LL_BINARY_MERGE]; | |
321 | else if (ATTR_UNSET(merge_attr)) { | |
322 | if (!default_ll_merge) | |
323 | return &ll_merge_drv[LL_TEXT_MERGE]; | |
324 | else | |
325 | name = default_ll_merge; | |
326 | } | |
327 | else | |
328 | name = merge_attr; | |
329 | ||
330 | for (fn = ll_user_merge; fn; fn = fn->next) | |
331 | if (!strcmp(fn->name, name)) | |
332 | return fn; | |
333 | ||
334 | for (i = 0; i < ARRAY_SIZE(ll_merge_drv); i++) | |
335 | if (!strcmp(ll_merge_drv[i].name, name)) | |
336 | return &ll_merge_drv[i]; | |
337 | ||
338 | /* default to the 3-way */ | |
339 | return &ll_merge_drv[LL_TEXT_MERGE]; | |
340 | } | |
341 | ||
23a64c9e | 342 | static int git_path_check_merge(const char *path, struct git_attr_check check[2]) |
525ab639 | 343 | { |
23a64c9e JH |
344 | if (!check[0].attr) { |
345 | check[0].attr = git_attr("merge"); | |
346 | check[1].attr = git_attr("conflict-marker-size"); | |
347 | } | |
d932f4eb | 348 | return git_check_attr(path, 2, check); |
525ab639 JH |
349 | } |
350 | ||
f217f0e8 EB |
351 | static void normalize_file(mmfile_t *mm, const char *path) |
352 | { | |
353 | struct strbuf strbuf = STRBUF_INIT; | |
354 | if (renormalize_buffer(path, mm->ptr, mm->size, &strbuf)) { | |
355 | free(mm->ptr); | |
356 | mm->size = strbuf.len; | |
357 | mm->ptr = strbuf_detach(&strbuf, NULL); | |
358 | } | |
359 | } | |
360 | ||
525ab639 JH |
361 | int ll_merge(mmbuffer_t *result_buf, |
362 | const char *path, | |
f01de62e | 363 | mmfile_t *ancestor, const char *ancestor_label, |
525ab639 JH |
364 | mmfile_t *ours, const char *our_label, |
365 | mmfile_t *theirs, const char *their_label, | |
712516bc | 366 | const struct ll_merge_options *opts) |
525ab639 | 367 | { |
23a64c9e | 368 | static struct git_attr_check check[2]; |
4fb40c2b | 369 | static const struct ll_merge_options default_opts; |
23a64c9e JH |
370 | const char *ll_driver_name = NULL; |
371 | int marker_size = DEFAULT_CONFLICT_MARKER_SIZE; | |
525ab639 JH |
372 | const struct ll_merge_driver *driver; |
373 | ||
4fb40c2b JN |
374 | if (!opts) |
375 | opts = &default_opts; | |
712516bc JN |
376 | |
377 | if (opts->renormalize) { | |
f217f0e8 EB |
378 | normalize_file(ancestor, path); |
379 | normalize_file(ours, path); | |
380 | normalize_file(theirs, path); | |
381 | } | |
23a64c9e JH |
382 | if (!git_path_check_merge(path, check)) { |
383 | ll_driver_name = check[0].value; | |
384 | if (check[1].value) { | |
385 | marker_size = atoi(check[1].value); | |
386 | if (marker_size <= 0) | |
387 | marker_size = DEFAULT_CONFLICT_MARKER_SIZE; | |
388 | } | |
389 | } | |
525ab639 | 390 | driver = find_ll_merge_driver(ll_driver_name); |
712516bc | 391 | if (opts->virtual_ancestor && driver->recursive) |
525ab639 | 392 | driver = find_ll_merge_driver(driver->recursive); |
f01de62e | 393 | return driver->fn(driver, result_buf, path, ancestor, ancestor_label, |
23a64c9e | 394 | ours, our_label, theirs, their_label, |
712516bc | 395 | opts, marker_size); |
525ab639 | 396 | } |
8588567c JH |
397 | |
398 | int ll_merge_marker_size(const char *path) | |
399 | { | |
400 | static struct git_attr_check check; | |
401 | int marker_size = DEFAULT_CONFLICT_MARKER_SIZE; | |
402 | ||
403 | if (!check.attr) | |
404 | check.attr = git_attr("conflict-marker-size"); | |
d932f4eb | 405 | if (!git_check_attr(path, 1, &check) && check.value) { |
8588567c JH |
406 | marker_size = atoi(check.value); |
407 | if (marker_size <= 0) | |
408 | marker_size = DEFAULT_CONFLICT_MARKER_SIZE; | |
409 | } | |
410 | return marker_size; | |
525ab639 | 411 | } |