1 /*
2 * "git difftool" builtin command
3 *
4 * This is a wrapper around the GIT_EXTERNAL_DIFF-compatible
5 * git-difftool--helper script.
6 *
7 * This script exports GIT_EXTERNAL_DIFF and GIT_PAGER for use by git.
8 * The GIT_DIFF* variables are exported for use by git-difftool--helper.
9 *
10 * Any arguments that are unknown to this script are forwarded to 'git diff'.
11 *
12 * Copyright (C) 2016 Johannes Schindelin
13 */
14 #define USE_THE_INDEX_COMPATIBILITY_MACROS
15 #include "cache.h"
16 #include "config.h"
17 #include "builtin.h"
18 #include "run-command.h"
19 #include "exec-cmd.h"
20 #include "parse-options.h"
21 #include "strvec.h"
22 #include "strbuf.h"
23 #include "lockfile.h"
24 #include "object-store.h"
25 #include "dir.h"
26 #include "entry.h"
27
28 static int trust_exit_code;
29
30 static const char *const builtin_difftool_usage[] = {
31 N_("git difftool [<options>] [<commit> [<commit>]] [--] [<path>...]"),
32 NULL
33 };
34
difftool_config(const char * var,const char * value,void * cb)35 static int difftool_config(const char *var, const char *value, void *cb)
36 {
37 if (!strcmp(var, "difftool.trustexitcode")) {
38 trust_exit_code = git_config_bool(var, value);
39 return 0;
40 }
41
42 return git_default_config(var, value, cb);
43 }
44
print_tool_help(void)45 static int print_tool_help(void)
46 {
47 const char *argv[] = { "mergetool", "--tool-help=diff", NULL };
48 return run_command_v_opt(argv, RUN_GIT_CMD);
49 }
50
parse_index_info(char * p,int * mode1,int * mode2,struct object_id * oid1,struct object_id * oid2,char * status)51 static int parse_index_info(char *p, int *mode1, int *mode2,
52 struct object_id *oid1, struct object_id *oid2,
53 char *status)
54 {
55 if (*p != ':')
56 return error("expected ':', got '%c'", *p);
57 *mode1 = (int)strtol(p + 1, &p, 8);
58 if (*p != ' ')
59 return error("expected ' ', got '%c'", *p);
60 *mode2 = (int)strtol(p + 1, &p, 8);
61 if (*p != ' ')
62 return error("expected ' ', got '%c'", *p);
63 if (parse_oid_hex(++p, oid1, (const char **)&p))
64 return error("expected object ID, got '%s'", p);
65 if (*p != ' ')
66 return error("expected ' ', got '%c'", *p);
67 if (parse_oid_hex(++p, oid2, (const char **)&p))
68 return error("expected object ID, got '%s'", p);
69 if (*p != ' ')
70 return error("expected ' ', got '%c'", *p);
71 *status = *++p;
72 if (!*status)
73 return error("missing status");
74 if (p[1] && !isdigit(p[1]))
75 return error("unexpected trailer: '%s'", p + 1);
76 return 0;
77 }
78
79 /*
80 * Remove any trailing slash from $workdir
81 * before starting to avoid double slashes in symlink targets.
82 */
add_path(struct strbuf * buf,size_t base_len,const char * path)83 static void add_path(struct strbuf *buf, size_t base_len, const char *path)
84 {
85 strbuf_setlen(buf, base_len);
86 if (buf->len && buf->buf[buf->len - 1] != '/')
87 strbuf_addch(buf, '/');
88 strbuf_addstr(buf, path);
89 }
90
91 /*
92 * Determine whether we can simply reuse the file in the worktree.
93 */
use_wt_file(const char * workdir,const char * name,struct object_id * oid)94 static int use_wt_file(const char *workdir, const char *name,
95 struct object_id *oid)
96 {
97 struct strbuf buf = STRBUF_INIT;
98 struct stat st;
99 int use = 0;
100
101 strbuf_addstr(&buf, workdir);
102 add_path(&buf, buf.len, name);
103
104 if (!lstat(buf.buf, &st) && !S_ISLNK(st.st_mode)) {
105 struct object_id wt_oid;
106 int fd = open(buf.buf, O_RDONLY);
107
108 if (fd >= 0 &&
109 !index_fd(&the_index, &wt_oid, fd, &st, OBJ_BLOB, name, 0)) {
110 if (is_null_oid(oid)) {
111 oidcpy(oid, &wt_oid);
112 use = 1;
113 } else if (oideq(oid, &wt_oid))
114 use = 1;
115 }
116 }
117
118 strbuf_release(&buf);
119
120 return use;
121 }
122
123 struct working_tree_entry {
124 struct hashmap_entry entry;
125 char path[FLEX_ARRAY];
126 };
127
working_tree_entry_cmp(const void * unused_cmp_data,const struct hashmap_entry * eptr,const struct hashmap_entry * entry_or_key,const void * unused_keydata)128 static int working_tree_entry_cmp(const void *unused_cmp_data,
129 const struct hashmap_entry *eptr,
130 const struct hashmap_entry *entry_or_key,
131 const void *unused_keydata)
132 {
133 const struct working_tree_entry *a, *b;
134
135 a = container_of(eptr, const struct working_tree_entry, entry);
136 b = container_of(entry_or_key, const struct working_tree_entry, entry);
137
138 return strcmp(a->path, b->path);
139 }
140
141 /*
142 * The `left` and `right` entries hold paths for the symlinks hashmap,
143 * and a SHA-1 surrounded by brief text for submodules.
144 */
145 struct pair_entry {
146 struct hashmap_entry entry;
147 char left[PATH_MAX], right[PATH_MAX];
148 const char path[FLEX_ARRAY];
149 };
150
pair_cmp(const void * unused_cmp_data,const struct hashmap_entry * eptr,const struct hashmap_entry * entry_or_key,const void * unused_keydata)151 static int pair_cmp(const void *unused_cmp_data,
152 const struct hashmap_entry *eptr,
153 const struct hashmap_entry *entry_or_key,
154 const void *unused_keydata)
155 {
156 const struct pair_entry *a, *b;
157
158 a = container_of(eptr, const struct pair_entry, entry);
159 b = container_of(entry_or_key, const struct pair_entry, entry);
160
161 return strcmp(a->path, b->path);
162 }
163
add_left_or_right(struct hashmap * map,const char * path,const char * content,int is_right)164 static void add_left_or_right(struct hashmap *map, const char *path,
165 const char *content, int is_right)
166 {
167 struct pair_entry *e, *existing;
168
169 FLEX_ALLOC_STR(e, path, path);
170 hashmap_entry_init(&e->entry, strhash(path));
171 existing = hashmap_get_entry(map, e, entry, NULL);
172 if (existing) {
173 free(e);
174 e = existing;
175 } else {
176 e->left[0] = e->right[0] = '\0';
177 hashmap_add(map, &e->entry);
178 }
179 strlcpy(is_right ? e->right : e->left, content, PATH_MAX);
180 }
181
182 struct path_entry {
183 struct hashmap_entry entry;
184 char path[FLEX_ARRAY];
185 };
186
path_entry_cmp(const void * unused_cmp_data,const struct hashmap_entry * eptr,const struct hashmap_entry * entry_or_key,const void * key)187 static int path_entry_cmp(const void *unused_cmp_data,
188 const struct hashmap_entry *eptr,
189 const struct hashmap_entry *entry_or_key,
190 const void *key)
191 {
192 const struct path_entry *a, *b;
193
194 a = container_of(eptr, const struct path_entry, entry);
195 b = container_of(entry_or_key, const struct path_entry, entry);
196
197 return strcmp(a->path, key ? key : b->path);
198 }
199
changed_files(struct hashmap * result,const char * index_path,const char * workdir)200 static void changed_files(struct hashmap *result, const char *index_path,
201 const char *workdir)
202 {
203 struct child_process update_index = CHILD_PROCESS_INIT;
204 struct child_process diff_files = CHILD_PROCESS_INIT;
205 struct strbuf index_env = STRBUF_INIT, buf = STRBUF_INIT;
206 const char *git_dir = absolute_path(get_git_dir()), *env[] = {
207 NULL, NULL
208 };
209 FILE *fp;
210
211 strbuf_addf(&index_env, "GIT_INDEX_FILE=%s", index_path);
212 env[0] = index_env.buf;
213
214 strvec_pushl(&update_index.args,
215 "--git-dir", git_dir, "--work-tree", workdir,
216 "update-index", "--really-refresh", "-q",
217 "--unmerged", NULL);
218 update_index.no_stdin = 1;
219 update_index.no_stdout = 1;
220 update_index.no_stderr = 1;
221 update_index.git_cmd = 1;
222 update_index.use_shell = 0;
223 update_index.clean_on_exit = 1;
224 update_index.dir = workdir;
225 update_index.env = env;
226 /* Ignore any errors of update-index */
227 run_command(&update_index);
228
229 strvec_pushl(&diff_files.args,
230 "--git-dir", git_dir, "--work-tree", workdir,
231 "diff-files", "--name-only", "-z", NULL);
232 diff_files.no_stdin = 1;
233 diff_files.git_cmd = 1;
234 diff_files.use_shell = 0;
235 diff_files.clean_on_exit = 1;
236 diff_files.out = -1;
237 diff_files.dir = workdir;
238 diff_files.env = env;
239 if (start_command(&diff_files))
240 die("could not obtain raw diff");
241 fp = xfdopen(diff_files.out, "r");
242 while (!strbuf_getline_nul(&buf, fp)) {
243 struct path_entry *entry;
244 FLEX_ALLOC_STR(entry, path, buf.buf);
245 hashmap_entry_init(&entry->entry, strhash(buf.buf));
246 hashmap_add(result, &entry->entry);
247 }
248 fclose(fp);
249 if (finish_command(&diff_files))
250 die("diff-files did not exit properly");
251 strbuf_release(&index_env);
252 strbuf_release(&buf);
253 }
254
ensure_leading_directories(char * path)255 static int ensure_leading_directories(char *path)
256 {
257 switch (safe_create_leading_directories(path)) {
258 case SCLD_OK:
259 case SCLD_EXISTS:
260 return 0;
261 default:
262 return error(_("could not create leading directories "
263 "of '%s'"), path);
264 }
265 }
266
267 /*
268 * Unconditional writing of a plain regular file is what
269 * "git difftool --dir-diff" wants to do for symlinks. We are preparing two
270 * temporary directories to be fed to a Git-unaware tool that knows how to
271 * show a diff of two directories (e.g. "diff -r A B").
272 *
273 * Because the tool is Git-unaware, if a symbolic link appears in either of
274 * these temporary directories, it will try to dereference and show the
275 * difference of the target of the symbolic link, which is not what we want,
276 * as the goal of the dir-diff mode is to produce an output that is logically
277 * equivalent to what "git diff" produces.
278 *
279 * Most importantly, we want to get textual comparison of the result of the
280 * readlink(2). get_symlink() provides that---it returns the contents of
281 * the symlink that gets written to a regular file to force the external tool
282 * to compare the readlink(2) result as text, even on a filesystem that is
283 * capable of doing a symbolic link.
284 */
get_symlink(const struct object_id * oid,const char * path)285 static char *get_symlink(const struct object_id *oid, const char *path)
286 {
287 char *data;
288 if (is_null_oid(oid)) {
289 /* The symlink is unknown to Git so read from the filesystem */
290 struct strbuf link = STRBUF_INIT;
291 if (has_symlinks) {
292 if (strbuf_readlink(&link, path, strlen(path)))
293 die(_("could not read symlink %s"), path);
294 } else if (strbuf_read_file(&link, path, 128))
295 die(_("could not read symlink file %s"), path);
296
297 data = strbuf_detach(&link, NULL);
298 } else {
299 enum object_type type;
300 unsigned long size;
301 data = read_object_file(oid, &type, &size);
302 if (!data)
303 die(_("could not read object %s for symlink %s"),
304 oid_to_hex(oid), path);
305 }
306
307 return data;
308 }
309
checkout_path(unsigned mode,struct object_id * oid,const char * path,const struct checkout * state)310 static int checkout_path(unsigned mode, struct object_id *oid,
311 const char *path, const struct checkout *state)
312 {
313 struct cache_entry *ce;
314 int ret;
315
316 ce = make_transient_cache_entry(mode, oid, path, 0, NULL);
317 ret = checkout_entry(ce, state, NULL, NULL);
318
319 discard_cache_entry(ce);
320 return ret;
321 }
322
write_file_in_directory(struct strbuf * dir,size_t dir_len,const char * path,const char * content)323 static void write_file_in_directory(struct strbuf *dir, size_t dir_len,
324 const char *path, const char *content)
325 {
326 add_path(dir, dir_len, path);
327 ensure_leading_directories(dir->buf);
328 unlink(dir->buf);
329 write_file(dir->buf, "%s", content);
330 }
331
332 /* Write the file contents for the left and right sides of the difftool
333 * dir-diff representation for submodules and symlinks. Symlinks and submodules
334 * are written as regular text files so that external diff tools can diff them
335 * as text files, resulting in behavior that is analogous to to what "git diff"
336 * displays for symlink and submodule diffs.
337 */
write_standin_files(struct pair_entry * entry,struct strbuf * ldir,size_t ldir_len,struct strbuf * rdir,size_t rdir_len)338 static void write_standin_files(struct pair_entry *entry,
339 struct strbuf *ldir, size_t ldir_len,
340 struct strbuf *rdir, size_t rdir_len)
341 {
342 if (*entry->left)
343 write_file_in_directory(ldir, ldir_len, entry->path, entry->left);
344 if (*entry->right)
345 write_file_in_directory(rdir, rdir_len, entry->path, entry->right);
346 }
347
run_dir_diff(const char * extcmd,int symlinks,const char * prefix,struct child_process * child)348 static int run_dir_diff(const char *extcmd, int symlinks, const char *prefix,
349 struct child_process *child)
350 {
351 struct strbuf info = STRBUF_INIT, lpath = STRBUF_INIT;
352 struct strbuf rpath = STRBUF_INIT, buf = STRBUF_INIT;
353 struct strbuf ldir = STRBUF_INIT, rdir = STRBUF_INIT;
354 struct strbuf wtdir = STRBUF_INIT;
355 struct strbuf tmpdir = STRBUF_INIT;
356 char *lbase_dir = NULL, *rbase_dir = NULL;
357 size_t ldir_len, rdir_len, wtdir_len;
358 const char *workdir, *tmp;
359 int ret = 0, i;
360 FILE *fp = NULL;
361 struct hashmap working_tree_dups = HASHMAP_INIT(working_tree_entry_cmp,
362 NULL);
363 struct hashmap submodules = HASHMAP_INIT(pair_cmp, NULL);
364 struct hashmap symlinks2 = HASHMAP_INIT(pair_cmp, NULL);
365 struct hashmap_iter iter;
366 struct pair_entry *entry;
367 struct index_state wtindex;
368 struct checkout lstate, rstate;
369 int flags = RUN_GIT_CMD, err = 0;
370 const char *helper_argv[] = { "difftool--helper", NULL, NULL, NULL };
371 struct hashmap wt_modified, tmp_modified;
372 int indices_loaded = 0;
373
374 workdir = get_git_work_tree();
375
376 /* Setup temp directories */
377 tmp = getenv("TMPDIR");
378 strbuf_add_absolute_path(&tmpdir, tmp ? tmp : "/tmp");
379 strbuf_trim_trailing_dir_sep(&tmpdir);
380 strbuf_addstr(&tmpdir, "/git-difftool.XXXXXX");
381 if (!mkdtemp(tmpdir.buf)) {
382 ret = error("could not create '%s'", tmpdir.buf);
383 goto finish;
384 }
385 strbuf_addf(&ldir, "%s/left/", tmpdir.buf);
386 strbuf_addf(&rdir, "%s/right/", tmpdir.buf);
387 strbuf_addstr(&wtdir, workdir);
388 if (!wtdir.len || !is_dir_sep(wtdir.buf[wtdir.len - 1]))
389 strbuf_addch(&wtdir, '/');
390 mkdir(ldir.buf, 0700);
391 mkdir(rdir.buf, 0700);
392
393 memset(&wtindex, 0, sizeof(wtindex));
394
395 memset(&lstate, 0, sizeof(lstate));
396 lstate.base_dir = lbase_dir = xstrdup(ldir.buf);
397 lstate.base_dir_len = ldir.len;
398 lstate.force = 1;
399 memset(&rstate, 0, sizeof(rstate));
400 rstate.base_dir = rbase_dir = xstrdup(rdir.buf);
401 rstate.base_dir_len = rdir.len;
402 rstate.force = 1;
403
404 ldir_len = ldir.len;
405 rdir_len = rdir.len;
406 wtdir_len = wtdir.len;
407
408 child->no_stdin = 1;
409 child->git_cmd = 1;
410 child->use_shell = 0;
411 child->clean_on_exit = 1;
412 child->dir = prefix;
413 child->out = -1;
414 if (start_command(child))
415 die("could not obtain raw diff");
416 fp = xfdopen(child->out, "r");
417
418 /* Build index info for left and right sides of the diff */
419 i = 0;
420 while (!strbuf_getline_nul(&info, fp)) {
421 int lmode, rmode;
422 struct object_id loid, roid;
423 char status;
424 const char *src_path, *dst_path;
425
426 if (starts_with(info.buf, "::"))
427 die(N_("combined diff formats ('-c' and '--cc') are "
428 "not supported in\n"
429 "directory diff mode ('-d' and '--dir-diff')."));
430
431 if (parse_index_info(info.buf, &lmode, &rmode, &loid, &roid,
432 &status))
433 break;
434 if (strbuf_getline_nul(&lpath, fp))
435 break;
436 src_path = lpath.buf;
437
438 i++;
439 if (status != 'C' && status != 'R') {
440 dst_path = src_path;
441 } else {
442 if (strbuf_getline_nul(&rpath, fp))
443 break;
444 dst_path = rpath.buf;
445 }
446
447 if (S_ISGITLINK(lmode) || S_ISGITLINK(rmode)) {
448 strbuf_reset(&buf);
449 strbuf_addf(&buf, "Subproject commit %s",
450 oid_to_hex(&loid));
451 add_left_or_right(&submodules, src_path, buf.buf, 0);
452 strbuf_reset(&buf);
453 strbuf_addf(&buf, "Subproject commit %s",
454 oid_to_hex(&roid));
455 if (oideq(&loid, &roid))
456 strbuf_addstr(&buf, "-dirty");
457 add_left_or_right(&submodules, dst_path, buf.buf, 1);
458 continue;
459 }
460
461 if (S_ISLNK(lmode)) {
462 char *content = get_symlink(&loid, src_path);
463 add_left_or_right(&symlinks2, src_path, content, 0);
464 free(content);
465 }
466
467 if (S_ISLNK(rmode)) {
468 char *content = get_symlink(&roid, dst_path);
469 add_left_or_right(&symlinks2, dst_path, content, 1);
470 free(content);
471 }
472
473 if (lmode && status != 'C') {
474 if (checkout_path(lmode, &loid, src_path, &lstate)) {
475 ret = error("could not write '%s'", src_path);
476 goto finish;
477 }
478 }
479
480 if (rmode && !S_ISLNK(rmode)) {
481 struct working_tree_entry *entry;
482
483 /* Avoid duplicate working_tree entries */
484 FLEX_ALLOC_STR(entry, path, dst_path);
485 hashmap_entry_init(&entry->entry, strhash(dst_path));
486 if (hashmap_get(&working_tree_dups, &entry->entry,
487 NULL)) {
488 free(entry);
489 continue;
490 }
491 hashmap_add(&working_tree_dups, &entry->entry);
492
493 if (!use_wt_file(workdir, dst_path, &roid)) {
494 if (checkout_path(rmode, &roid, dst_path,
495 &rstate)) {
496 ret = error("could not write '%s'",
497 dst_path);
498 goto finish;
499 }
500 } else if (!is_null_oid(&roid)) {
501 /*
502 * Changes in the working tree need special
503 * treatment since they are not part of the
504 * index.
505 */
506 struct cache_entry *ce2 =
507 make_cache_entry(&wtindex, rmode, &roid,
508 dst_path, 0, 0);
509
510 add_index_entry(&wtindex, ce2,
511 ADD_CACHE_JUST_APPEND);
512
513 add_path(&rdir, rdir_len, dst_path);
514 if (ensure_leading_directories(rdir.buf)) {
515 ret = error("could not create "
516 "directory for '%s'",
517 dst_path);
518 goto finish;
519 }
520 add_path(&wtdir, wtdir_len, dst_path);
521 if (symlinks) {
522 if (symlink(wtdir.buf, rdir.buf)) {
523 ret = error_errno("could not symlink '%s' to '%s'", wtdir.buf, rdir.buf);
524 goto finish;
525 }
526 } else {
527 struct stat st;
528 if (stat(wtdir.buf, &st))
529 st.st_mode = 0644;
530 if (copy_file(rdir.buf, wtdir.buf,
531 st.st_mode)) {
532 ret = error("could not copy '%s' to '%s'", wtdir.buf, rdir.buf);
533 goto finish;
534 }
535 }
536 }
537 }
538 }
539
540 fclose(fp);
541 fp = NULL;
542 if (finish_command(child)) {
543 ret = error("error occurred running diff --raw");
544 goto finish;
545 }
546
547 if (!i)
548 goto finish;
549
550 /*
551 * Changes to submodules require special treatment.This loop writes a
552 * temporary file to both the left and right directories to show the
553 * change in the recorded SHA1 for the submodule.
554 */
555 hashmap_for_each_entry(&submodules, &iter, entry,
556 entry /* member name */) {
557 write_standin_files(entry, &ldir, ldir_len, &rdir, rdir_len);
558 }
559
560 /*
561 * Symbolic links require special treatment. The standard "git diff"
562 * shows only the link itself, not the contents of the link target.
563 * This loop replicates that behavior.
564 */
565 hashmap_for_each_entry(&symlinks2, &iter, entry,
566 entry /* member name */) {
567
568 write_standin_files(entry, &ldir, ldir_len, &rdir, rdir_len);
569 }
570
571 strbuf_setlen(&ldir, ldir_len);
572 helper_argv[1] = ldir.buf;
573 strbuf_setlen(&rdir, rdir_len);
574 helper_argv[2] = rdir.buf;
575
576 if (extcmd) {
577 helper_argv[0] = extcmd;
578 flags = 0;
579 } else
580 setenv("GIT_DIFFTOOL_DIRDIFF", "true", 1);
581 ret = run_command_v_opt(helper_argv, flags);
582
583 /* TODO: audit for interaction with sparse-index. */
584 ensure_full_index(&wtindex);
585
586 /*
587 * If the diff includes working copy files and those
588 * files were modified during the diff, then the changes
589 * should be copied back to the working tree.
590 * Do not copy back files when symlinks are used and the
591 * external tool did not replace the original link with a file.
592 *
593 * These hashes are loaded lazily since they aren't needed
594 * in the common case of --symlinks and the difftool updating
595 * files through the symlink.
596 */
597 hashmap_init(&wt_modified, path_entry_cmp, NULL, wtindex.cache_nr);
598 hashmap_init(&tmp_modified, path_entry_cmp, NULL, wtindex.cache_nr);
599
600 for (i = 0; i < wtindex.cache_nr; i++) {
601 struct hashmap_entry dummy;
602 const char *name = wtindex.cache[i]->name;
603 struct stat st;
604
605 add_path(&rdir, rdir_len, name);
606 if (lstat(rdir.buf, &st))
607 continue;
608
609 if ((symlinks && S_ISLNK(st.st_mode)) || !S_ISREG(st.st_mode))
610 continue;
611
612 if (!indices_loaded) {
613 struct lock_file lock = LOCK_INIT;
614 strbuf_reset(&buf);
615 strbuf_addf(&buf, "%s/wtindex", tmpdir.buf);
616 if (hold_lock_file_for_update(&lock, buf.buf, 0) < 0 ||
617 write_locked_index(&wtindex, &lock, COMMIT_LOCK)) {
618 ret = error("could not write %s", buf.buf);
619 goto finish;
620 }
621 changed_files(&wt_modified, buf.buf, workdir);
622 strbuf_setlen(&rdir, rdir_len);
623 changed_files(&tmp_modified, buf.buf, rdir.buf);
624 add_path(&rdir, rdir_len, name);
625 indices_loaded = 1;
626 }
627
628 hashmap_entry_init(&dummy, strhash(name));
629 if (hashmap_get(&tmp_modified, &dummy, name)) {
630 add_path(&wtdir, wtdir_len, name);
631 if (hashmap_get(&wt_modified, &dummy, name)) {
632 warning(_("both files modified: '%s' and '%s'."),
633 wtdir.buf, rdir.buf);
634 warning(_("working tree file has been left."));
635 warning("%s", "");
636 err = 1;
637 } else if (unlink(wtdir.buf) ||
638 copy_file(wtdir.buf, rdir.buf, st.st_mode))
639 warning_errno(_("could not copy '%s' to '%s'"),
640 rdir.buf, wtdir.buf);
641 }
642 }
643
644 if (err) {
645 warning(_("temporary files exist in '%s'."), tmpdir.buf);
646 warning(_("you may want to cleanup or recover these."));
647 ret = 1;
648 } else {
649 remove_dir_recursively(&tmpdir, 0);
650 if (ret)
651 warning(_("failed: %d"), ret);
652 }
653
654 finish:
655 if (fp)
656 fclose(fp);
657
658 free(lbase_dir);
659 free(rbase_dir);
660 strbuf_release(&ldir);
661 strbuf_release(&rdir);
662 strbuf_release(&wtdir);
663 strbuf_release(&buf);
664 strbuf_release(&tmpdir);
665
666 return (ret < 0) ? 1 : ret;
667 }
668
run_file_diff(int prompt,const char * prefix,struct child_process * child)669 static int run_file_diff(int prompt, const char *prefix,
670 struct child_process *child)
671 {
672 const char *env[] = {
673 "GIT_PAGER=", "GIT_EXTERNAL_DIFF=git-difftool--helper", NULL,
674 NULL
675 };
676
677 if (prompt > 0)
678 env[2] = "GIT_DIFFTOOL_PROMPT=true";
679 else if (!prompt)
680 env[2] = "GIT_DIFFTOOL_NO_PROMPT=true";
681
682 child->git_cmd = 1;
683 child->dir = prefix;
684 strvec_pushv(&child->env_array, env);
685
686 return run_command(child);
687 }
688
cmd_difftool(int argc,const char ** argv,const char * prefix)689 int cmd_difftool(int argc, const char **argv, const char *prefix)
690 {
691 int use_gui_tool = 0, dir_diff = 0, prompt = -1, symlinks = 0,
692 tool_help = 0, no_index = 0;
693 static char *difftool_cmd = NULL, *extcmd = NULL;
694 struct option builtin_difftool_options[] = {
695 OPT_BOOL('g', "gui", &use_gui_tool,
696 N_("use `diff.guitool` instead of `diff.tool`")),
697 OPT_BOOL('d', "dir-diff", &dir_diff,
698 N_("perform a full-directory diff")),
699 OPT_SET_INT_F('y', "no-prompt", &prompt,
700 N_("do not prompt before launching a diff tool"),
701 0, PARSE_OPT_NONEG),
702 OPT_SET_INT_F(0, "prompt", &prompt, NULL,
703 1, PARSE_OPT_NONEG | PARSE_OPT_HIDDEN),
704 OPT_BOOL(0, "symlinks", &symlinks,
705 N_("use symlinks in dir-diff mode")),
706 OPT_STRING('t', "tool", &difftool_cmd, N_("tool"),
707 N_("use the specified diff tool")),
708 OPT_BOOL(0, "tool-help", &tool_help,
709 N_("print a list of diff tools that may be used with "
710 "`--tool`")),
711 OPT_BOOL(0, "trust-exit-code", &trust_exit_code,
712 N_("make 'git-difftool' exit when an invoked diff "
713 "tool returns a non-zero exit code")),
714 OPT_STRING('x', "extcmd", &extcmd, N_("command"),
715 N_("specify a custom command for viewing diffs")),
716 OPT_BOOL(0, "no-index", &no_index, N_("passed to `diff`")),
717 OPT_END()
718 };
719 struct child_process child = CHILD_PROCESS_INIT;
720
721 git_config(difftool_config, NULL);
722 symlinks = has_symlinks;
723
724 argc = parse_options(argc, argv, prefix, builtin_difftool_options,
725 builtin_difftool_usage, PARSE_OPT_KEEP_UNKNOWN |
726 PARSE_OPT_KEEP_DASHDASH);
727
728 if (tool_help)
729 return print_tool_help();
730
731 if (!no_index && !startup_info->have_repository)
732 die(_("difftool requires worktree or --no-index"));
733
734 if (!no_index){
735 setup_work_tree();
736 setenv(GIT_DIR_ENVIRONMENT, absolute_path(get_git_dir()), 1);
737 setenv(GIT_WORK_TREE_ENVIRONMENT, absolute_path(get_git_work_tree()), 1);
738 } else if (dir_diff)
739 die(_("--dir-diff is incompatible with --no-index"));
740
741 if (use_gui_tool + !!difftool_cmd + !!extcmd > 1)
742 die(_("--gui, --tool and --extcmd are mutually exclusive"));
743
744 if (use_gui_tool)
745 setenv("GIT_MERGETOOL_GUI", "true", 1);
746 else if (difftool_cmd) {
747 if (*difftool_cmd)
748 setenv("GIT_DIFF_TOOL", difftool_cmd, 1);
749 else
750 die(_("no <tool> given for --tool=<tool>"));
751 }
752
753 if (extcmd) {
754 if (*extcmd)
755 setenv("GIT_DIFFTOOL_EXTCMD", extcmd, 1);
756 else
757 die(_("no <cmd> given for --extcmd=<cmd>"));
758 }
759
760 setenv("GIT_DIFFTOOL_TRUST_EXIT_CODE",
761 trust_exit_code ? "true" : "false", 1);
762
763 /*
764 * In directory diff mode, 'git-difftool--helper' is called once
765 * to compare the a / b directories. In file diff mode, 'git diff'
766 * will invoke a separate instance of 'git-difftool--helper' for
767 * each file that changed.
768 */
769 strvec_push(&child.args, "diff");
770 if (no_index)
771 strvec_push(&child.args, "--no-index");
772 if (dir_diff)
773 strvec_pushl(&child.args, "--raw", "--no-abbrev", "-z", NULL);
774 strvec_pushv(&child.args, argv);
775
776 if (dir_diff)
777 return run_dir_diff(extcmd, symlinks, prefix, &child);
778 return run_file_diff(prompt, prefix, &child);
779 }
780