git-apply: start using the index file information.
[git/git.git] / diff.c
CommitLineData
be3cfa85
JH
1/*
2 * Copyright (C) 2005 Junio C Hamano
3 */
4#include <sys/types.h>
5#include <sys/wait.h>
532149d7 6#include <signal.h>
86436c28
JH
7#include "cache.h"
8#include "diff.h"
427dcb4b 9#include "diffcore.h"
86436c28 10
d19938ab 11static const char *diff_opts = "-pu";
5c97558c 12static unsigned char null_sha1[20] = { 0, };
427dcb4b 13
427dcb4b 14static int reverse_diff;
81e50eab
JH
15static int generate_patch;
16static int line_termination = '\n';
17static int inter_name_termination = '\t';
86436c28 18
be3cfa85 19static const char *external_diff(void)
86436c28 20{
d19938ab 21 static const char *external_diff_cmd = NULL;
be3cfa85
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22 static int done_preparing = 0;
23
24 if (done_preparing)
25 return external_diff_cmd;
26
86436c28
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27 /*
28 * Default values above are meant to match the
29 * Linux kernel development style. Examples of
30 * alternative styles you can specify via environment
31 * variables are:
32 *
86436c28
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33 * GIT_DIFF_OPTS="-c";
34 */
d19938ab
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35 if (gitenv("GIT_EXTERNAL_DIFF"))
36 external_diff_cmd = gitenv("GIT_EXTERNAL_DIFF");
be3cfa85
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37
38 /* In case external diff fails... */
d19938ab 39 diff_opts = gitenv("GIT_DIFF_OPTS") ? : diff_opts;
be3cfa85
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40
41 done_preparing = 1;
42 return external_diff_cmd;
86436c28
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43}
44
45/* Help to copy the thing properly quoted for the shell safety.
46 * any single quote is replaced with '\'', and the caller is
47 * expected to enclose the result within a single quote pair.
48 *
49 * E.g.
50 * original sq_expand result
51 * name ==> name ==> 'name'
52 * a b ==> a b ==> 'a b'
53 * a'b ==> a'\''b ==> 'a'\''b'
54 */
55static char *sq_expand(const char *src)
56{
57 static char *buf = NULL;
58 int cnt, c;
59 const char *cp;
60 char *bp;
61
57fe64a4 62 /* count bytes needed to store the quoted string. */
86436c28
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63 for (cnt = 1, cp = src; *cp; cnt++, cp++)
64 if (*cp == '\'')
65 cnt += 3;
66
812666c8 67 buf = xmalloc(cnt);
86436c28
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68 bp = buf;
69 while ((c = *src++)) {
70 if (c != '\'')
71 *bp++ = c;
72 else {
73 bp = strcpy(bp, "'\\''");
74 bp += 4;
75 }
76 }
77 *bp = 0;
78 return buf;
79}
80
be3cfa85 81static struct diff_tempfile {
427dcb4b 82 const char *name; /* filename external diff should read from */
be3cfa85
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83 char hex[41];
84 char mode[10];
85 char tmp_path[50];
86} diff_temp[2];
87
915838c3
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88static void builtin_diff(const char *name_a,
89 const char *name_b,
57fe64a4 90 struct diff_tempfile *temp,
427dcb4b 91 const char *xfrm_msg)
86436c28 92{
9669e17a 93 int i, next_at, cmd_size;
c983370e 94 const char *diff_cmd = "diff -L'%s%s' -L'%s%s'";
6fa28064 95 const char *diff_arg = "'%s' '%s'||:"; /* "||:" is to return 0 */
2f978138
JH
96 const char *input_name_sq[2];
97 const char *path0[2];
98 const char *path1[2];
915838c3 99 const char *name_sq[2];
2f978138 100 char *cmd;
915838c3
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101
102 name_sq[0] = sq_expand(name_a);
103 name_sq[1] = sq_expand(name_b);
104
c983370e
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105 /* diff_cmd and diff_arg have 6 %s in total which makes
106 * the sum of these strings 12 bytes larger than required.
be3cfa85 107 * we use 2 spaces around diff-opts, and we need to count
c983370e 108 * terminating NUL, so we subtract 9 here.
be3cfa85 109 */
9669e17a 110 cmd_size = (strlen(diff_cmd) + strlen(diff_opts) +
c983370e 111 strlen(diff_arg) - 9);
2f978138
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112 for (i = 0; i < 2; i++) {
113 input_name_sq[i] = sq_expand(temp[i].name);
114 if (!strcmp(temp[i].name, "/dev/null")) {
115 path0[i] = "/dev/null";
116 path1[i] = "";
2f978138 117 } else {
0980d9b3 118 path0[i] = i ? "b/" : "a/";
915838c3 119 path1[i] = name_sq[i];
2f978138
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120 }
121 cmd_size += (strlen(path0[i]) + strlen(path1[i]) +
c983370e 122 strlen(input_name_sq[i]));
2f978138 123 }
be3cfa85 124
2f978138
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125 cmd = xmalloc(cmd_size);
126
127 next_at = 0;
be3cfa85 128 next_at += snprintf(cmd+next_at, cmd_size-next_at,
2f978138 129 diff_cmd,
c983370e 130 path0[0], path1[0], path0[1], path1[1]);
be3cfa85
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131 next_at += snprintf(cmd+next_at, cmd_size-next_at,
132 " %s ", diff_opts);
133 next_at += snprintf(cmd+next_at, cmd_size-next_at,
2f978138
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134 diff_arg, input_name_sq[0], input_name_sq[1]);
135
915838c3 136 printf("diff --git a/%s b/%s\n", name_a, name_b);
c983370e 137 if (!path1[0][0])
b58f23b3 138 printf("new file mode %s\n", temp[1].mode);
c983370e 139 else if (!path1[1][0])
b58f23b3 140 printf("deleted file mode %s\n", temp[0].mode);
273b9834 141 else {
b58f23b3
JH
142 if (strcmp(temp[0].mode, temp[1].mode)) {
143 printf("old mode %s\n", temp[0].mode);
144 printf("new mode %s\n", temp[1].mode);
145 }
427dcb4b
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146 if (xfrm_msg && xfrm_msg[0])
147 fputs(xfrm_msg, stdout);
148
273b9834
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149 if (strncmp(temp[0].mode, temp[1].mode, 3))
150 /* we do not run diff between different kind
151 * of objects.
152 */
b28858bf
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153 exit(0);
154 }
c983370e 155 fflush(NULL);
be3cfa85 156 execlp("/bin/sh","sh", "-c", cmd, NULL);
86436c28
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157}
158
427dcb4b
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159struct diff_filespec *alloc_filespec(const char *path)
160{
161 int namelen = strlen(path);
162 struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
163 spec->path = (char *)(spec + 1);
164 strcpy(spec->path, path);
81e50eab 165 spec->should_free = spec->should_munmap = 0;
427dcb4b
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166 spec->xfrm_flags = 0;
167 spec->size = 0;
09d74b3b 168 spec->data = NULL;
81e50eab
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169 spec->mode = 0;
170 memset(spec->sha1, 0, 20);
427dcb4b
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171 return spec;
172}
173
174void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
175 unsigned short mode)
176{
81e50eab
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177 if (mode) { /* just playing defensive */
178 spec->mode = mode;
179 memcpy(spec->sha1, sha1, 20);
180 spec->sha1_valid = !!memcmp(sha1, null_sha1, 20);
181 }
427dcb4b
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182}
183
b46f0b6d
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184/*
185 * Given a name and sha1 pair, if the dircache tells us the file in
186 * the work tree has that object contents, return true, so that
187 * prepare_temp_file() does not have to inflate and extract.
188 */
189static int work_tree_matches(const char *name, const unsigned char *sha1)
190{
191 struct cache_entry *ce;
192 struct stat st;
193 int pos, len;
5c97558c 194
b46f0b6d
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195 /* We do not read the cache ourselves here, because the
196 * benchmark with my previous version that always reads cache
197 * shows that it makes things worse for diff-tree comparing
198 * two linux-2.6 kernel trees in an already checked out work
915838c3 199 * tree. This is because most diff-tree comparisons deal with
b46f0b6d
JH
200 * only a small number of files, while reading the cache is
201 * expensive for a large project, and its cost outweighs the
202 * savings we get by not inflating the object to a temporary
203 * file. Practically, this code only helps when we are used
204 * by diff-cache --cached, which does read the cache before
205 * calling us.
57fe64a4 206 */
b46f0b6d
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207 if (!active_cache)
208 return 0;
209
210 len = strlen(name);
211 pos = cache_name_pos(name, len);
212 if (pos < 0)
213 return 0;
214 ce = active_cache[pos];
b28858bf 215 if ((lstat(name, &st) < 0) ||
427dcb4b 216 !S_ISREG(st.st_mode) || /* careful! */
5d728c84 217 ce_match_stat(ce, &st) ||
b46f0b6d
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218 memcmp(sha1, ce->sha1, 20))
219 return 0;
427dcb4b
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220 /* we return 1 only when we can stat, it is a regular file,
221 * stat information matches, and sha1 recorded in the cache
222 * matches. I.e. we know the file in the work tree really is
223 * the same as the <name, sha1> pair.
224 */
b46f0b6d
JH
225 return 1;
226}
227
427dcb4b
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228/*
229 * While doing rename detection and pickaxe operation, we may need to
230 * grab the data for the blob (or file) for our own in-core comparison.
231 * diff_filespec has data and size fields for this purpose.
232 */
233int diff_populate_filespec(struct diff_filespec *s)
234{
235 int err = 0;
81e50eab 236 if (!DIFF_FILE_VALID(s))
427dcb4b
JH
237 die("internal error: asking to populate invalid file.");
238 if (S_ISDIR(s->mode))
239 return -1;
240
241 if (s->data)
242 return err;
243 if (!s->sha1_valid ||
244 work_tree_matches(s->path, s->sha1)) {
245 struct stat st;
246 int fd;
247 if (lstat(s->path, &st) < 0) {
248 if (errno == ENOENT) {
249 err_empty:
250 err = -1;
251 empty:
252 s->data = "";
253 s->size = 0;
254 return err;
255 }
256 }
257 s->size = st.st_size;
258 if (!s->size)
259 goto empty;
260 if (S_ISLNK(st.st_mode)) {
261 int ret;
262 s->data = xmalloc(s->size);
263 s->should_free = 1;
264 ret = readlink(s->path, s->data, s->size);
265 if (ret < 0) {
266 free(s->data);
267 goto err_empty;
268 }
269 return 0;
270 }
271 fd = open(s->path, O_RDONLY);
272 if (fd < 0)
273 goto err_empty;
274 s->data = mmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
275 s->should_munmap = 1;
276 close(fd);
277 }
278 else {
279 char type[20];
280 s->data = read_sha1_file(s->sha1, type, &s->size);
281 s->should_free = 1;
282 }
283 return 0;
284}
285
286void diff_free_filespec_data(struct diff_filespec *s)
287{
288 if (s->should_free)
289 free(s->data);
290 else if (s->should_munmap)
291 munmap(s->data, s->size);
292 s->should_free = s->should_munmap = 0;
09d74b3b 293 s->data = NULL;
427dcb4b
JH
294}
295
b28858bf
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296static void prep_temp_blob(struct diff_tempfile *temp,
297 void *blob,
298 unsigned long size,
299 unsigned char *sha1,
300 int mode)
301{
302 int fd;
303
304 strcpy(temp->tmp_path, ".diff_XXXXXX");
305 fd = mkstemp(temp->tmp_path);
306 if (fd < 0)
307 die("unable to create temp-file");
308 if (write(fd, blob, size) != size)
309 die("unable to write temp-file");
310 close(fd);
311 temp->name = temp->tmp_path;
312 strcpy(temp->hex, sha1_to_hex(sha1));
313 temp->hex[40] = 0;
314 sprintf(temp->mode, "%06o", mode);
315}
316
be3cfa85
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317static void prepare_temp_file(const char *name,
318 struct diff_tempfile *temp,
427dcb4b 319 struct diff_filespec *one)
86436c28 320{
81e50eab 321 if (!DIFF_FILE_VALID(one)) {
be3cfa85 322 not_a_valid_file:
532149d7
JH
323 /* A '-' entry produces this for file-2, and
324 * a '+' entry produces this for file-1.
325 */
be3cfa85
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326 temp->name = "/dev/null";
327 strcpy(temp->hex, ".");
328 strcpy(temp->mode, ".");
86436c28
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329 return;
330 }
be3cfa85 331
5c97558c 332 if (!one->sha1_valid ||
427dcb4b 333 work_tree_matches(name, one->sha1)) {
be3cfa85 334 struct stat st;
427dcb4b 335 if (lstat(name, &st) < 0) {
be3cfa85
JH
336 if (errno == ENOENT)
337 goto not_a_valid_file;
427dcb4b 338 die("stat(%s): %s", name, strerror(errno));
be3cfa85 339 }
b28858bf
JH
340 if (S_ISLNK(st.st_mode)) {
341 int ret;
342 char *buf, buf_[1024];
343 buf = ((sizeof(buf_) < st.st_size) ?
344 xmalloc(st.st_size) : buf_);
345 ret = readlink(name, buf, st.st_size);
346 if (ret < 0)
347 die("readlink(%s)", name);
348 prep_temp_blob(temp, buf, st.st_size,
349 (one->sha1_valid ?
427dcb4b 350 one->sha1 : null_sha1),
b28858bf
JH
351 (one->sha1_valid ?
352 one->mode : S_IFLNK));
353 }
354 else {
427dcb4b
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355 /* we can borrow from the file in the work tree */
356 temp->name = name;
b28858bf
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357 if (!one->sha1_valid)
358 strcpy(temp->hex, sha1_to_hex(null_sha1));
359 else
427dcb4b 360 strcpy(temp->hex, sha1_to_hex(one->sha1));
b28858bf
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361 sprintf(temp->mode, "%06o",
362 S_IFREG |ce_permissions(st.st_mode));
363 }
364 return;
be3cfa85
JH
365 }
366 else {
427dcb4b
JH
367 if (diff_populate_filespec(one))
368 die("cannot read data blob for %s", one->path);
369 prep_temp_blob(temp, one->data, one->size,
370 one->sha1, one->mode);
be3cfa85
JH
371 }
372}
373
374static void remove_tempfile(void)
375{
376 int i;
377
378 for (i = 0; i < 2; i++)
379 if (diff_temp[i].name == diff_temp[i].tmp_path) {
380 unlink(diff_temp[i].name);
381 diff_temp[i].name = NULL;
382 }
383}
384
532149d7
JH
385static void remove_tempfile_on_signal(int signo)
386{
387 remove_tempfile();
388}
389
be3cfa85
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390/* An external diff command takes:
391 *
392 * diff-cmd name infile1 infile1-sha1 infile1-mode \
5c97558c 393 * infile2 infile2-sha1 infile2-mode [ rename-to ]
be3cfa85
JH
394 *
395 */
5c97558c
JH
396static void run_external_diff(const char *name,
397 const char *other,
427dcb4b
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398 struct diff_filespec *one,
399 struct diff_filespec *two,
400 const char *xfrm_msg)
be3cfa85
JH
401{
402 struct diff_tempfile *temp = diff_temp;
532149d7
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403 pid_t pid;
404 int status;
be3cfa85
JH
405 static int atexit_asked = 0;
406
77eb2720
JH
407 if (one && two) {
408 prepare_temp_file(name, &temp[0], one);
915838c3 409 prepare_temp_file(other ? : name, &temp[1], two);
77eb2720
JH
410 if (! atexit_asked &&
411 (temp[0].name == temp[0].tmp_path ||
412 temp[1].name == temp[1].tmp_path)) {
413 atexit_asked = 1;
414 atexit(remove_tempfile);
415 }
532149d7 416 signal(SIGINT, remove_tempfile_on_signal);
be3cfa85
JH
417 }
418
419 fflush(NULL);
420 pid = fork();
421 if (pid < 0)
422 die("unable to fork");
423 if (!pid) {
424 const char *pgm = external_diff();
5c97558c
JH
425 if (pgm) {
426 if (one && two) {
427dcb4b 427 const char *exec_arg[10];
5c97558c
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428 const char **arg = &exec_arg[0];
429 *arg++ = pgm;
430 *arg++ = name;
431 *arg++ = temp[0].name;
432 *arg++ = temp[0].hex;
433 *arg++ = temp[0].mode;
434 *arg++ = temp[1].name;
435 *arg++ = temp[1].hex;
436 *arg++ = temp[1].mode;
427dcb4b 437 if (other) {
5c97558c 438 *arg++ = other;
427dcb4b
JH
439 *arg++ = xfrm_msg;
440 }
09d74b3b 441 *arg = NULL;
5c97558c
JH
442 execvp(pgm, (char *const*) exec_arg);
443 }
77eb2720
JH
444 else
445 execlp(pgm, pgm, name, NULL);
446 }
be3cfa85
JH
447 /*
448 * otherwise we use the built-in one.
449 */
77eb2720 450 if (one && two)
427dcb4b 451 builtin_diff(name, other ? : name, temp, xfrm_msg);
77eb2720
JH
452 else
453 printf("* Unmerged path %s\n", name);
be3cfa85
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454 exit(0);
455 }
6fa28064
JH
456 if (waitpid(pid, &status, 0) < 0 ||
457 !WIFEXITED(status) || WEXITSTATUS(status)) {
458 /* Earlier we did not check the exit status because
532149d7 459 * diff exits non-zero if files are different, and
6fa28064
JH
460 * we are not interested in knowing that. It was a
461 * mistake which made it harder to quit a diff-*
462 * session that uses the git-apply-patch-script as
463 * the GIT_EXTERNAL_DIFF. A custom GIT_EXTERNAL_DIFF
464 * should also exit non-zero only when it wants to
465 * abort the entire diff-* session.
532149d7
JH
466 */
467 remove_tempfile();
6fa28064
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468 fprintf(stderr, "external diff died, stopping at %s.\n", name);
469 exit(1);
532149d7 470 }
be3cfa85
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471 remove_tempfile();
472}
473
6b14d7fa 474void diff_setup(int reverse_diff_)
5c97558c 475{
6b14d7fa 476 reverse_diff = reverse_diff_;
5c97558c
JH
477}
478
6b14d7fa
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479struct diff_queue_struct diff_queued_diff;
480
481void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
5c97558c 482{
6b14d7fa
JH
483 if (queue->alloc <= queue->nr) {
484 queue->alloc = alloc_nr(queue->alloc);
485 queue->queue = xrealloc(queue->queue,
486 sizeof(dp) * queue->alloc);
81e50eab 487 }
6b14d7fa 488 queue->queue[queue->nr++] = dp;
5c97558c
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489}
490
52e95789 491struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
6b14d7fa
JH
492 struct diff_filespec *one,
493 struct diff_filespec *two)
5c97558c 494{
52e95789 495 struct diff_filepair *dp = xmalloc(sizeof(*dp));
427dcb4b
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496 dp->one = one;
497 dp->two = two;
f7c1512a 498 dp->score = 0;
427dcb4b 499 dp->orig_order = queue->nr;
f7c1512a 500 dp->rename_rank = 0;
6b14d7fa 501 diff_q(queue, dp);
427dcb4b 502 return dp;
5c97558c
JH
503}
504
52e95789 505static void diff_flush_raw(struct diff_filepair *p)
5c97558c 506{
b6d8f309
JH
507 int two_paths;
508 char status[10];
509 switch (p->status) {
510 case 'C': case 'R':
511 two_paths = 1;
512 sprintf(status, "%c%1d", p->status, p->score);
513 break;
514 default:
515 two_paths = 0;
516 status[0] = p->status;
517 status[1] = 0;
518 break;
6b14d7fa 519 }
81e50eab
JH
520 printf(":%06o %06o %s ",
521 p->one->mode, p->two->mode, sha1_to_hex(p->one->sha1));
b6d8f309
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522 printf("%s %s%c%s",
523 sha1_to_hex(p->two->sha1),
524 status,
525 inter_name_termination,
526 p->one->path);
527 if (two_paths)
528 printf("%c%s", inter_name_termination, p->two->path);
529 putchar(line_termination);
5c97558c
JH
530}
531
f7c1512a 532int diff_unmodified_pair(struct diff_filepair *p)
5c97558c 533{
427dcb4b
JH
534 /* This function is written stricter than necessary to support
535 * the currently implemented transformers, but the idea is to
52e95789 536 * let transformers to produce diff_filepairs any way they want,
427dcb4b 537 * and filter and clean them up here before producing the output.
5c97558c 538 */
6b14d7fa
JH
539 struct diff_filespec *one, *two;
540
541 if (DIFF_PAIR_UNMERGED(p))
542 return 0; /* unmerged is interesting */
5c97558c 543
6b14d7fa
JH
544 one = p->one;
545 two = p->two;
5c97558c 546
427dcb4b 547 /* deletion, addition, mode change and renames are all interesting. */
81e50eab
JH
548 if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
549 (one->mode != two->mode) ||
427dcb4b
JH
550 strcmp(one->path, two->path))
551 return 0;
57fe64a4 552
427dcb4b
JH
553 /* both are valid and point at the same path. that is, we are
554 * dealing with a change.
57fe64a4 555 */
427dcb4b
JH
556 if (one->sha1_valid && two->sha1_valid &&
557 !memcmp(one->sha1, two->sha1, sizeof(one->sha1)))
558 return 1; /* no change */
559 if (!one->sha1_valid && !two->sha1_valid)
560 return 1; /* both look at the same file on the filesystem. */
561 return 0;
57fe64a4
JH
562}
563
b6d8f309 564static void diff_flush_patch(struct diff_filepair *p)
f7c1512a
JH
565{
566 const char *name, *other;
b6d8f309 567 char msg_[PATH_MAX*2+200], *msg;
f7c1512a
JH
568
569 /* diffcore_prune() keeps "stay" entries for diff-raw
570 * copy/rename detection, but when we are generating
571 * patches we do not need them.
572 */
573 if (diff_unmodified_pair(p))
574 return;
575
576 name = p->one->path;
577 other = (strcmp(name, p->two->path) ? p->two->path : NULL);
578 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
579 (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
580 return; /* no tree diffs in patch format */
581
b6d8f309
JH
582 switch (p->status) {
583 case 'C':
584 sprintf(msg_,
585 "similarity index %d%%\n"
586 "copy from %s\n"
587 "copy to %s\n",
588 (int)(0.5 + p->score * 100/MAX_SCORE),
589 p->one->path, p->two->path);
590 msg = msg_;
591 break;
592 case 'R':
593 sprintf(msg_,
594 "similarity index %d%%\n"
595 "rename old %s\n"
596 "rename new %s\n",
597 (int)(0.5 + p->score * 100/MAX_SCORE),
598 p->one->path, p->two->path);
599 msg = msg_;
600 break;
601 default:
602 msg = NULL;
603 }
604
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605 if (DIFF_PAIR_UNMERGED(p))
606 run_external_diff(name, NULL, NULL, NULL, NULL);
607 else
608 run_external_diff(name, other, p->one, p->two, msg);
609}
610
611int diff_needs_to_stay(struct diff_queue_struct *q, int i,
612 struct diff_filespec *it)
613{
614 /* If it will be used in later entry (either stay or used
615 * as the source of rename/copy), we need to copy, not rename.
616 */
617 while (i < q->nr) {
618 struct diff_filepair *p = q->queue[i++];
619 if (!DIFF_FILE_VALID(p->two))
620 continue; /* removed is fine */
621 if (strcmp(p->one->path, it->path))
622 continue; /* not relevant */
623
624 /* p has its src set to *it and it is not a delete;
625 * it will be used for in-place change, rename/copy,
626 * or just stays there. We cannot rename it out.
627 */
628 return 1;
629 }
630 return 0;
631}
632
633static int diff_used_as_source(struct diff_queue_struct *q, int lim,
634 struct diff_filespec *it)
635{
636 int i;
637 for (i = 0; i < lim; i++) {
638 struct diff_filepair *p = q->queue[i++];
639 if (!strcmp(p->one->path, it->path))
640 return 1;
641 }
642 return 0;
643}
644
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645void diffcore_prune(void)
646{
647 /*
648 * Although rename/copy detection wants to have "no-change"
649 * entries fed into them, the downstream do not need to see
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650 * them, unless we had rename/copy for the same path earlier.
651 * This function removes such entries.
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652 *
653 * The applications that use rename/copy should:
654 *
655 * (1) feed change and "no-change" entries via diff_queue().
656 * (2) call diffcore_rename, and any other future diffcore_xxx
657 * that would benefit by still having "no-change" entries.
658 * (3) call diffcore_prune
659 * (4) call other diffcore_xxx that do not need to see
660 * "no-change" entries.
f7c1512a 661 * (5) call diff_flush().
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662 */
663 struct diff_queue_struct *q = &diff_queued_diff;
664 struct diff_queue_struct outq;
665 int i;
666
667 outq.queue = NULL;
668 outq.nr = outq.alloc = 0;
669
670 for (i = 0; i < q->nr; i++) {
671 struct diff_filepair *p = q->queue[i];
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672 if (!diff_unmodified_pair(p) ||
673 diff_used_as_source(q, i, p->one))
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674 diff_q(&outq, p);
675 else
f7c1512a 676 free(p);
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677 }
678 free(q->queue);
679 *q = outq;
680 return;
681}
682
38c6f780 683int diff_queue_is_empty(void)
57fe64a4 684{
38c6f780 685 struct diff_queue_struct *q = &diff_queued_diff;
f7c1512a 686 return q->nr == 0;
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687}
688
b6d8f309 689void diff_flush(int diff_output_style, int resolve_rename_copy)
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690{
691 struct diff_queue_struct *q = &diff_queued_diff;
692 int i;
693
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694 generate_patch = 0;
695 switch (diff_output_style) {
696 case DIFF_FORMAT_HUMAN:
697 line_termination = '\n';
698 inter_name_termination = '\t';
699 break;
700 case DIFF_FORMAT_MACHINE:
701 line_termination = inter_name_termination = 0;
702 break;
703 case DIFF_FORMAT_PATCH:
704 generate_patch = 1;
705 break;
706 }
f7c1512a 707 for (i = 0; i < q->nr; i++) {
f7c1512a 708 struct diff_filepair *p = q->queue[i];
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709 if (resolve_rename_copy) {
710 if (DIFF_PAIR_UNMERGED(p))
711 p->status = 'U';
712 else if (!DIFF_FILE_VALID((p)->one))
713 p->status = 'N';
714 else if (!DIFF_FILE_VALID((p)->two))
715 p->status = 'D';
716 else if (strcmp(p->one->path, p->two->path)) {
717 /* This is rename or copy. Which one is it? */
718 if (diff_needs_to_stay(q, i+1, p->one))
719 p->status = 'C';
720 else
721 p->status = 'R';
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722 }
723 else
b6d8f309 724 p->status = 'M';
f7c1512a 725 }
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726 if (generate_patch)
727 diff_flush_patch(p);
728 else
729 diff_flush_raw(p);
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730 }
731
427dcb4b 732 for (i = 0; i < q->nr; i++) {
52e95789 733 struct diff_filepair *p = q->queue[i];
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734 diff_free_filespec_data(p->one);
735 diff_free_filespec_data(p->two);
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736 free(p);
737 }
738 free(q->queue);
739 q->queue = NULL;
740 q->nr = q->alloc = 0;
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741}
742
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743void diff_addremove(int addremove, unsigned mode,
744 const unsigned char *sha1,
745 const char *base, const char *path)
be3cfa85 746{
77eb2720 747 char concatpath[PATH_MAX];
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748 struct diff_filespec *one, *two;
749
750 /* This may look odd, but it is a preparation for
751 * feeding "there are unchanged files which should
752 * not produce diffs, but when you are doing copy
753 * detection you would need them, so here they are"
754 * entries to the diff-core. They will be prefixed
755 * with something like '=' or '*' (I haven't decided
756 * which but should not make any difference).
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757 * Feeding the same new and old to diff_change()
758 * also has the same effect. diffcore_prune() should
759 * be used to filter uninteresting ones out before the
760 * final output happens.
427dcb4b 761 */
7ca45252 762 if (reverse_diff)
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763 addremove = (addremove == '+' ? '-' :
764 addremove == '-' ? '+' : addremove);
7ca45252 765
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766 if (!path) path = "";
767 sprintf(concatpath, "%s%s", base, path);
768 one = alloc_filespec(concatpath);
769 two = alloc_filespec(concatpath);
be3cfa85 770
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771 if (addremove != '+')
772 fill_filespec(one, sha1, mode);
773 if (addremove != '-')
774 fill_filespec(two, sha1, mode);
5c97558c 775
38c6f780 776 diff_queue(&diff_queued_diff, one, two);
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777}
778
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779void diff_helper_input(unsigned old_mode,
780 unsigned new_mode,
781 const unsigned char *old_sha1,
782 const unsigned char *new_sha1,
783 const char *old_path,
784 int status,
785 int score,
786 const char *new_path)
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787{
788 struct diff_filespec *one, *two;
b6d8f309 789 struct diff_filepair *dp;
81e50eab 790
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791 one = alloc_filespec(old_path);
792 two = alloc_filespec(new_path);
793 if (old_mode)
794 fill_filespec(one, old_sha1, old_mode);
795 if (new_mode)
796 fill_filespec(two, new_sha1, new_mode);
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797 dp = diff_queue(&diff_queued_diff, one, two);
798 dp->score = score;
799 dp->status = status;
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800}
801
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802void diff_change(unsigned old_mode, unsigned new_mode,
803 const unsigned char *old_sha1,
804 const unsigned char *new_sha1,
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805 const char *base, const char *path)
806{
77eb2720 807 char concatpath[PATH_MAX];
427dcb4b 808 struct diff_filespec *one, *two;
77eb2720 809
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810 if (reverse_diff) {
811 unsigned tmp;
812 const unsigned char *tmp_c;
813 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
814 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
815 }
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816 if (!path) path = "";
817 sprintf(concatpath, "%s%s", base, path);
818 one = alloc_filespec(concatpath);
819 two = alloc_filespec(concatpath);
820 fill_filespec(one, old_sha1, old_mode);
821 fill_filespec(two, new_sha1, new_mode);
822
38c6f780 823 diff_queue(&diff_queued_diff, one, two);
77eb2720 824}
be3cfa85 825
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826void diff_unmerge(const char *path)
827{
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828 struct diff_filespec *one, *two;
829 one = alloc_filespec(path);
830 two = alloc_filespec(path);
831 diff_queue(&diff_queued_diff, one, two);
86436c28 832}