Merge branch 'tb/apply-with-crlf'
[git/git.git] / convert.c
1 #define NO_THE_INDEX_COMPATIBILITY_MACROS
2 #include "cache.h"
3 #include "config.h"
4 #include "attr.h"
5 #include "run-command.h"
6 #include "quote.h"
7 #include "sigchain.h"
8 #include "pkt-line.h"
9 #include "sub-process.h"
10
11 /*
12 * convert.c - convert a file when checking it out and checking it in.
13 *
14 * This should use the pathname to decide on whether it wants to do some
15 * more interesting conversions (automatic gzip/unzip, general format
16 * conversions etc etc), but by default it just does automatic CRLF<->LF
17 * translation when the "text" attribute or "auto_crlf" option is set.
18 */
19
20 /* Stat bits: When BIN is set, the txt bits are unset */
21 #define CONVERT_STAT_BITS_TXT_LF 0x1
22 #define CONVERT_STAT_BITS_TXT_CRLF 0x2
23 #define CONVERT_STAT_BITS_BIN 0x4
24
25 enum crlf_action {
26 CRLF_UNDEFINED,
27 CRLF_BINARY,
28 CRLF_TEXT,
29 CRLF_TEXT_INPUT,
30 CRLF_TEXT_CRLF,
31 CRLF_AUTO,
32 CRLF_AUTO_INPUT,
33 CRLF_AUTO_CRLF
34 };
35
36 struct text_stat {
37 /* NUL, CR, LF and CRLF counts */
38 unsigned nul, lonecr, lonelf, crlf;
39
40 /* These are just approximations! */
41 unsigned printable, nonprintable;
42 };
43
44 static void gather_stats(const char *buf, unsigned long size, struct text_stat *stats)
45 {
46 unsigned long i;
47
48 memset(stats, 0, sizeof(*stats));
49
50 for (i = 0; i < size; i++) {
51 unsigned char c = buf[i];
52 if (c == '\r') {
53 if (i+1 < size && buf[i+1] == '\n') {
54 stats->crlf++;
55 i++;
56 } else
57 stats->lonecr++;
58 continue;
59 }
60 if (c == '\n') {
61 stats->lonelf++;
62 continue;
63 }
64 if (c == 127)
65 /* DEL */
66 stats->nonprintable++;
67 else if (c < 32) {
68 switch (c) {
69 /* BS, HT, ESC and FF */
70 case '\b': case '\t': case '\033': case '\014':
71 stats->printable++;
72 break;
73 case 0:
74 stats->nul++;
75 /* fall through */
76 default:
77 stats->nonprintable++;
78 }
79 }
80 else
81 stats->printable++;
82 }
83
84 /* If file ends with EOF then don't count this EOF as non-printable. */
85 if (size >= 1 && buf[size-1] == '\032')
86 stats->nonprintable--;
87 }
88
89 /*
90 * The same heuristics as diff.c::mmfile_is_binary()
91 * We treat files with bare CR as binary
92 */
93 static int convert_is_binary(unsigned long size, const struct text_stat *stats)
94 {
95 if (stats->lonecr)
96 return 1;
97 if (stats->nul)
98 return 1;
99 if ((stats->printable >> 7) < stats->nonprintable)
100 return 1;
101 return 0;
102 }
103
104 static unsigned int gather_convert_stats(const char *data, unsigned long size)
105 {
106 struct text_stat stats;
107 int ret = 0;
108 if (!data || !size)
109 return 0;
110 gather_stats(data, size, &stats);
111 if (convert_is_binary(size, &stats))
112 ret |= CONVERT_STAT_BITS_BIN;
113 if (stats.crlf)
114 ret |= CONVERT_STAT_BITS_TXT_CRLF;
115 if (stats.lonelf)
116 ret |= CONVERT_STAT_BITS_TXT_LF;
117
118 return ret;
119 }
120
121 static const char *gather_convert_stats_ascii(const char *data, unsigned long size)
122 {
123 unsigned int convert_stats = gather_convert_stats(data, size);
124
125 if (convert_stats & CONVERT_STAT_BITS_BIN)
126 return "-text";
127 switch (convert_stats) {
128 case CONVERT_STAT_BITS_TXT_LF:
129 return "lf";
130 case CONVERT_STAT_BITS_TXT_CRLF:
131 return "crlf";
132 case CONVERT_STAT_BITS_TXT_LF | CONVERT_STAT_BITS_TXT_CRLF:
133 return "mixed";
134 default:
135 return "none";
136 }
137 }
138
139 const char *get_cached_convert_stats_ascii(const struct index_state *istate,
140 const char *path)
141 {
142 const char *ret;
143 unsigned long sz;
144 void *data = read_blob_data_from_index(istate, path, &sz);
145 ret = gather_convert_stats_ascii(data, sz);
146 free(data);
147 return ret;
148 }
149
150 const char *get_wt_convert_stats_ascii(const char *path)
151 {
152 const char *ret = "";
153 struct strbuf sb = STRBUF_INIT;
154 if (strbuf_read_file(&sb, path, 0) >= 0)
155 ret = gather_convert_stats_ascii(sb.buf, sb.len);
156 strbuf_release(&sb);
157 return ret;
158 }
159
160 static int text_eol_is_crlf(void)
161 {
162 if (auto_crlf == AUTO_CRLF_TRUE)
163 return 1;
164 else if (auto_crlf == AUTO_CRLF_INPUT)
165 return 0;
166 if (core_eol == EOL_CRLF)
167 return 1;
168 if (core_eol == EOL_UNSET && EOL_NATIVE == EOL_CRLF)
169 return 1;
170 return 0;
171 }
172
173 static enum eol output_eol(enum crlf_action crlf_action)
174 {
175 switch (crlf_action) {
176 case CRLF_BINARY:
177 return EOL_UNSET;
178 case CRLF_TEXT_CRLF:
179 return EOL_CRLF;
180 case CRLF_TEXT_INPUT:
181 return EOL_LF;
182 case CRLF_UNDEFINED:
183 case CRLF_AUTO_CRLF:
184 return EOL_CRLF;
185 case CRLF_AUTO_INPUT:
186 return EOL_LF;
187 case CRLF_TEXT:
188 case CRLF_AUTO:
189 /* fall through */
190 return text_eol_is_crlf() ? EOL_CRLF : EOL_LF;
191 }
192 warning("Illegal crlf_action %d\n", (int)crlf_action);
193 return core_eol;
194 }
195
196 static void check_safe_crlf(const char *path, enum crlf_action crlf_action,
197 struct text_stat *old_stats, struct text_stat *new_stats,
198 enum safe_crlf checksafe)
199 {
200 if (old_stats->crlf && !new_stats->crlf ) {
201 /*
202 * CRLFs would not be restored by checkout
203 */
204 if (checksafe == SAFE_CRLF_WARN)
205 warning(_("CRLF will be replaced by LF in %s.\n"
206 "The file will have its original line"
207 " endings in your working directory."), path);
208 else /* i.e. SAFE_CRLF_FAIL */
209 die(_("CRLF would be replaced by LF in %s."), path);
210 } else if (old_stats->lonelf && !new_stats->lonelf ) {
211 /*
212 * CRLFs would be added by checkout
213 */
214 if (checksafe == SAFE_CRLF_WARN)
215 warning(_("LF will be replaced by CRLF in %s.\n"
216 "The file will have its original line"
217 " endings in your working directory."), path);
218 else /* i.e. SAFE_CRLF_FAIL */
219 die(_("LF would be replaced by CRLF in %s"), path);
220 }
221 }
222
223 static int has_cr_in_index(const struct index_state *istate, const char *path)
224 {
225 unsigned long sz;
226 void *data;
227 int has_cr;
228
229 data = read_blob_data_from_index(istate, path, &sz);
230 if (!data)
231 return 0;
232 has_cr = memchr(data, '\r', sz) != NULL;
233 free(data);
234 return has_cr;
235 }
236
237 static int will_convert_lf_to_crlf(size_t len, struct text_stat *stats,
238 enum crlf_action crlf_action)
239 {
240 if (output_eol(crlf_action) != EOL_CRLF)
241 return 0;
242 /* No "naked" LF? Nothing to convert, regardless. */
243 if (!stats->lonelf)
244 return 0;
245
246 if (crlf_action == CRLF_AUTO || crlf_action == CRLF_AUTO_INPUT || crlf_action == CRLF_AUTO_CRLF) {
247 /* If we have any CR or CRLF line endings, we do not touch it */
248 /* This is the new safer autocrlf-handling */
249 if (stats->lonecr || stats->crlf)
250 return 0;
251
252 if (convert_is_binary(len, stats))
253 return 0;
254 }
255 return 1;
256
257 }
258
259 static int crlf_to_git(const struct index_state *istate,
260 const char *path, const char *src, size_t len,
261 struct strbuf *buf,
262 enum crlf_action crlf_action, enum safe_crlf checksafe)
263 {
264 struct text_stat stats;
265 char *dst;
266 int convert_crlf_into_lf;
267
268 if (crlf_action == CRLF_BINARY ||
269 (src && !len))
270 return 0;
271
272 /*
273 * If we are doing a dry-run and have no source buffer, there is
274 * nothing to analyze; we must assume we would convert.
275 */
276 if (!buf && !src)
277 return 1;
278
279 gather_stats(src, len, &stats);
280 /* Optimization: No CRLF? Nothing to convert, regardless. */
281 convert_crlf_into_lf = !!stats.crlf;
282
283 if (crlf_action == CRLF_AUTO || crlf_action == CRLF_AUTO_INPUT || crlf_action == CRLF_AUTO_CRLF) {
284 if (convert_is_binary(len, &stats))
285 return 0;
286 /*
287 * If the file in the index has any CR in it, do not
288 * convert. This is the new safer autocrlf handling,
289 * unless we want to renormalize in a merge or
290 * cherry-pick.
291 */
292 if ((checksafe != SAFE_CRLF_RENORMALIZE) &&
293 has_cr_in_index(istate, path))
294 convert_crlf_into_lf = 0;
295 }
296 if ((checksafe == SAFE_CRLF_WARN ||
297 (checksafe == SAFE_CRLF_FAIL)) && len) {
298 struct text_stat new_stats;
299 memcpy(&new_stats, &stats, sizeof(new_stats));
300 /* simulate "git add" */
301 if (convert_crlf_into_lf) {
302 new_stats.lonelf += new_stats.crlf;
303 new_stats.crlf = 0;
304 }
305 /* simulate "git checkout" */
306 if (will_convert_lf_to_crlf(len, &new_stats, crlf_action)) {
307 new_stats.crlf += new_stats.lonelf;
308 new_stats.lonelf = 0;
309 }
310 check_safe_crlf(path, crlf_action, &stats, &new_stats, checksafe);
311 }
312 if (!convert_crlf_into_lf)
313 return 0;
314
315 /*
316 * At this point all of our source analysis is done, and we are sure we
317 * would convert. If we are in dry-run mode, we can give an answer.
318 */
319 if (!buf)
320 return 1;
321
322 /* only grow if not in place */
323 if (strbuf_avail(buf) + buf->len < len)
324 strbuf_grow(buf, len - buf->len);
325 dst = buf->buf;
326 if (crlf_action == CRLF_AUTO || crlf_action == CRLF_AUTO_INPUT || crlf_action == CRLF_AUTO_CRLF) {
327 /*
328 * If we guessed, we already know we rejected a file with
329 * lone CR, and we can strip a CR without looking at what
330 * follow it.
331 */
332 do {
333 unsigned char c = *src++;
334 if (c != '\r')
335 *dst++ = c;
336 } while (--len);
337 } else {
338 do {
339 unsigned char c = *src++;
340 if (! (c == '\r' && (1 < len && *src == '\n')))
341 *dst++ = c;
342 } while (--len);
343 }
344 strbuf_setlen(buf, dst - buf->buf);
345 return 1;
346 }
347
348 static int crlf_to_worktree(const char *path, const char *src, size_t len,
349 struct strbuf *buf, enum crlf_action crlf_action)
350 {
351 char *to_free = NULL;
352 struct text_stat stats;
353
354 if (!len || output_eol(crlf_action) != EOL_CRLF)
355 return 0;
356
357 gather_stats(src, len, &stats);
358 if (!will_convert_lf_to_crlf(len, &stats, crlf_action))
359 return 0;
360
361 /* are we "faking" in place editing ? */
362 if (src == buf->buf)
363 to_free = strbuf_detach(buf, NULL);
364
365 strbuf_grow(buf, len + stats.lonelf);
366 for (;;) {
367 const char *nl = memchr(src, '\n', len);
368 if (!nl)
369 break;
370 if (nl > src && nl[-1] == '\r') {
371 strbuf_add(buf, src, nl + 1 - src);
372 } else {
373 strbuf_add(buf, src, nl - src);
374 strbuf_addstr(buf, "\r\n");
375 }
376 len -= nl + 1 - src;
377 src = nl + 1;
378 }
379 strbuf_add(buf, src, len);
380
381 free(to_free);
382 return 1;
383 }
384
385 struct filter_params {
386 const char *src;
387 unsigned long size;
388 int fd;
389 const char *cmd;
390 const char *path;
391 };
392
393 static int filter_buffer_or_fd(int in, int out, void *data)
394 {
395 /*
396 * Spawn cmd and feed the buffer contents through its stdin.
397 */
398 struct child_process child_process = CHILD_PROCESS_INIT;
399 struct filter_params *params = (struct filter_params *)data;
400 int write_err, status;
401 const char *argv[] = { NULL, NULL };
402
403 /* apply % substitution to cmd */
404 struct strbuf cmd = STRBUF_INIT;
405 struct strbuf path = STRBUF_INIT;
406 struct strbuf_expand_dict_entry dict[] = {
407 { "f", NULL, },
408 { NULL, NULL, },
409 };
410
411 /* quote the path to preserve spaces, etc. */
412 sq_quote_buf(&path, params->path);
413 dict[0].value = path.buf;
414
415 /* expand all %f with the quoted path */
416 strbuf_expand(&cmd, params->cmd, strbuf_expand_dict_cb, &dict);
417 strbuf_release(&path);
418
419 argv[0] = cmd.buf;
420
421 child_process.argv = argv;
422 child_process.use_shell = 1;
423 child_process.in = -1;
424 child_process.out = out;
425
426 if (start_command(&child_process))
427 return error("cannot fork to run external filter '%s'", params->cmd);
428
429 sigchain_push(SIGPIPE, SIG_IGN);
430
431 if (params->src) {
432 write_err = (write_in_full(child_process.in,
433 params->src, params->size) < 0);
434 if (errno == EPIPE)
435 write_err = 0;
436 } else {
437 write_err = copy_fd(params->fd, child_process.in);
438 if (write_err == COPY_WRITE_ERROR && errno == EPIPE)
439 write_err = 0;
440 }
441
442 if (close(child_process.in))
443 write_err = 1;
444 if (write_err)
445 error("cannot feed the input to external filter '%s'", params->cmd);
446
447 sigchain_pop(SIGPIPE);
448
449 status = finish_command(&child_process);
450 if (status)
451 error("external filter '%s' failed %d", params->cmd, status);
452
453 strbuf_release(&cmd);
454 return (write_err || status);
455 }
456
457 static int apply_single_file_filter(const char *path, const char *src, size_t len, int fd,
458 struct strbuf *dst, const char *cmd)
459 {
460 /*
461 * Create a pipeline to have the command filter the buffer's
462 * contents.
463 *
464 * (child --> cmd) --> us
465 */
466 int err = 0;
467 struct strbuf nbuf = STRBUF_INIT;
468 struct async async;
469 struct filter_params params;
470
471 memset(&async, 0, sizeof(async));
472 async.proc = filter_buffer_or_fd;
473 async.data = &params;
474 async.out = -1;
475 params.src = src;
476 params.size = len;
477 params.fd = fd;
478 params.cmd = cmd;
479 params.path = path;
480
481 fflush(NULL);
482 if (start_async(&async))
483 return 0; /* error was already reported */
484
485 if (strbuf_read(&nbuf, async.out, len) < 0) {
486 err = error("read from external filter '%s' failed", cmd);
487 }
488 if (close(async.out)) {
489 err = error("read from external filter '%s' failed", cmd);
490 }
491 if (finish_async(&async)) {
492 err = error("external filter '%s' failed", cmd);
493 }
494
495 if (!err) {
496 strbuf_swap(dst, &nbuf);
497 }
498 strbuf_release(&nbuf);
499 return !err;
500 }
501
502 #define CAP_CLEAN (1u<<0)
503 #define CAP_SMUDGE (1u<<1)
504 #define CAP_DELAY (1u<<2)
505
506 struct cmd2process {
507 struct subprocess_entry subprocess; /* must be the first member! */
508 unsigned int supported_capabilities;
509 };
510
511 static int subprocess_map_initialized;
512 static struct hashmap subprocess_map;
513
514 static int start_multi_file_filter_fn(struct subprocess_entry *subprocess)
515 {
516 static int versions[] = {2, 0};
517 static struct subprocess_capability capabilities[] = {
518 { "clean", CAP_CLEAN },
519 { "smudge", CAP_SMUDGE },
520 { "delay", CAP_DELAY },
521 { NULL, 0 }
522 };
523 struct cmd2process *entry = (struct cmd2process *)subprocess;
524 return subprocess_handshake(subprocess, "git-filter", versions, NULL,
525 capabilities,
526 &entry->supported_capabilities);
527 }
528
529 static void handle_filter_error(const struct strbuf *filter_status,
530 struct cmd2process *entry,
531 const unsigned int wanted_capability) {
532 if (!strcmp(filter_status->buf, "error"))
533 ; /* The filter signaled a problem with the file. */
534 else if (!strcmp(filter_status->buf, "abort") && wanted_capability) {
535 /*
536 * The filter signaled a permanent problem. Don't try to filter
537 * files with the same command for the lifetime of the current
538 * Git process.
539 */
540 entry->supported_capabilities &= ~wanted_capability;
541 } else {
542 /*
543 * Something went wrong with the protocol filter.
544 * Force shutdown and restart if another blob requires filtering.
545 */
546 error("external filter '%s' failed", entry->subprocess.cmd);
547 subprocess_stop(&subprocess_map, &entry->subprocess);
548 free(entry);
549 }
550 }
551
552 static int apply_multi_file_filter(const char *path, const char *src, size_t len,
553 int fd, struct strbuf *dst, const char *cmd,
554 const unsigned int wanted_capability,
555 struct delayed_checkout *dco)
556 {
557 int err;
558 int can_delay = 0;
559 struct cmd2process *entry;
560 struct child_process *process;
561 struct strbuf nbuf = STRBUF_INIT;
562 struct strbuf filter_status = STRBUF_INIT;
563 const char *filter_type;
564
565 if (!subprocess_map_initialized) {
566 subprocess_map_initialized = 1;
567 hashmap_init(&subprocess_map, cmd2process_cmp, NULL, 0);
568 entry = NULL;
569 } else {
570 entry = (struct cmd2process *)subprocess_find_entry(&subprocess_map, cmd);
571 }
572
573 fflush(NULL);
574
575 if (!entry) {
576 entry = xmalloc(sizeof(*entry));
577 entry->supported_capabilities = 0;
578
579 if (subprocess_start(&subprocess_map, &entry->subprocess, cmd, start_multi_file_filter_fn)) {
580 free(entry);
581 return 0;
582 }
583 }
584 process = &entry->subprocess.process;
585
586 if (!(entry->supported_capabilities & wanted_capability))
587 return 0;
588
589 if (wanted_capability & CAP_CLEAN)
590 filter_type = "clean";
591 else if (wanted_capability & CAP_SMUDGE)
592 filter_type = "smudge";
593 else
594 die("unexpected filter type");
595
596 sigchain_push(SIGPIPE, SIG_IGN);
597
598 assert(strlen(filter_type) < LARGE_PACKET_DATA_MAX - strlen("command=\n"));
599 err = packet_write_fmt_gently(process->in, "command=%s\n", filter_type);
600 if (err)
601 goto done;
602
603 err = strlen(path) > LARGE_PACKET_DATA_MAX - strlen("pathname=\n");
604 if (err) {
605 error("path name too long for external filter");
606 goto done;
607 }
608
609 err = packet_write_fmt_gently(process->in, "pathname=%s\n", path);
610 if (err)
611 goto done;
612
613 if ((entry->supported_capabilities & CAP_DELAY) &&
614 dco && dco->state == CE_CAN_DELAY) {
615 can_delay = 1;
616 err = packet_write_fmt_gently(process->in, "can-delay=1\n");
617 if (err)
618 goto done;
619 }
620
621 err = packet_flush_gently(process->in);
622 if (err)
623 goto done;
624
625 if (fd >= 0)
626 err = write_packetized_from_fd(fd, process->in);
627 else
628 err = write_packetized_from_buf(src, len, process->in);
629 if (err)
630 goto done;
631
632 err = subprocess_read_status(process->out, &filter_status);
633 if (err)
634 goto done;
635
636 if (can_delay && !strcmp(filter_status.buf, "delayed")) {
637 string_list_insert(&dco->filters, cmd);
638 string_list_insert(&dco->paths, path);
639 } else {
640 /* The filter got the blob and wants to send us a response. */
641 err = strcmp(filter_status.buf, "success");
642 if (err)
643 goto done;
644
645 err = read_packetized_to_strbuf(process->out, &nbuf) < 0;
646 if (err)
647 goto done;
648
649 err = subprocess_read_status(process->out, &filter_status);
650 if (err)
651 goto done;
652
653 err = strcmp(filter_status.buf, "success");
654 }
655
656 done:
657 sigchain_pop(SIGPIPE);
658
659 if (err)
660 handle_filter_error(&filter_status, entry, wanted_capability);
661 else
662 strbuf_swap(dst, &nbuf);
663 strbuf_release(&nbuf);
664 return !err;
665 }
666
667
668 int async_query_available_blobs(const char *cmd, struct string_list *available_paths)
669 {
670 int err;
671 char *line;
672 struct cmd2process *entry;
673 struct child_process *process;
674 struct strbuf filter_status = STRBUF_INIT;
675
676 assert(subprocess_map_initialized);
677 entry = (struct cmd2process *)subprocess_find_entry(&subprocess_map, cmd);
678 if (!entry) {
679 error("external filter '%s' is not available anymore although "
680 "not all paths have been filtered", cmd);
681 return 0;
682 }
683 process = &entry->subprocess.process;
684 sigchain_push(SIGPIPE, SIG_IGN);
685
686 err = packet_write_fmt_gently(
687 process->in, "command=list_available_blobs\n");
688 if (err)
689 goto done;
690
691 err = packet_flush_gently(process->in);
692 if (err)
693 goto done;
694
695 while ((line = packet_read_line(process->out, NULL))) {
696 const char *path;
697 if (skip_prefix(line, "pathname=", &path))
698 string_list_insert(available_paths, xstrdup(path));
699 else
700 ; /* ignore unknown keys */
701 }
702
703 err = subprocess_read_status(process->out, &filter_status);
704 if (err)
705 goto done;
706
707 err = strcmp(filter_status.buf, "success");
708
709 done:
710 sigchain_pop(SIGPIPE);
711
712 if (err)
713 handle_filter_error(&filter_status, entry, 0);
714 return !err;
715 }
716
717 static struct convert_driver {
718 const char *name;
719 struct convert_driver *next;
720 const char *smudge;
721 const char *clean;
722 const char *process;
723 int required;
724 } *user_convert, **user_convert_tail;
725
726 static int apply_filter(const char *path, const char *src, size_t len,
727 int fd, struct strbuf *dst, struct convert_driver *drv,
728 const unsigned int wanted_capability,
729 struct delayed_checkout *dco)
730 {
731 const char *cmd = NULL;
732
733 if (!drv)
734 return 0;
735
736 if (!dst)
737 return 1;
738
739 if ((wanted_capability & CAP_CLEAN) && !drv->process && drv->clean)
740 cmd = drv->clean;
741 else if ((wanted_capability & CAP_SMUDGE) && !drv->process && drv->smudge)
742 cmd = drv->smudge;
743
744 if (cmd && *cmd)
745 return apply_single_file_filter(path, src, len, fd, dst, cmd);
746 else if (drv->process && *drv->process)
747 return apply_multi_file_filter(path, src, len, fd, dst,
748 drv->process, wanted_capability, dco);
749
750 return 0;
751 }
752
753 static int read_convert_config(const char *var, const char *value, void *cb)
754 {
755 const char *key, *name;
756 int namelen;
757 struct convert_driver *drv;
758
759 /*
760 * External conversion drivers are configured using
761 * "filter.<name>.variable".
762 */
763 if (parse_config_key(var, "filter", &name, &namelen, &key) < 0 || !name)
764 return 0;
765 for (drv = user_convert; drv; drv = drv->next)
766 if (!strncmp(drv->name, name, namelen) && !drv->name[namelen])
767 break;
768 if (!drv) {
769 drv = xcalloc(1, sizeof(struct convert_driver));
770 drv->name = xmemdupz(name, namelen);
771 *user_convert_tail = drv;
772 user_convert_tail = &(drv->next);
773 }
774
775 /*
776 * filter.<name>.smudge and filter.<name>.clean specifies
777 * the command line:
778 *
779 * command-line
780 *
781 * The command-line will not be interpolated in any way.
782 */
783
784 if (!strcmp("smudge", key))
785 return git_config_string(&drv->smudge, var, value);
786
787 if (!strcmp("clean", key))
788 return git_config_string(&drv->clean, var, value);
789
790 if (!strcmp("process", key))
791 return git_config_string(&drv->process, var, value);
792
793 if (!strcmp("required", key)) {
794 drv->required = git_config_bool(var, value);
795 return 0;
796 }
797
798 return 0;
799 }
800
801 static int count_ident(const char *cp, unsigned long size)
802 {
803 /*
804 * "$Id: 0000000000000000000000000000000000000000 $" <=> "$Id$"
805 */
806 int cnt = 0;
807 char ch;
808
809 while (size) {
810 ch = *cp++;
811 size--;
812 if (ch != '$')
813 continue;
814 if (size < 3)
815 break;
816 if (memcmp("Id", cp, 2))
817 continue;
818 ch = cp[2];
819 cp += 3;
820 size -= 3;
821 if (ch == '$')
822 cnt++; /* $Id$ */
823 if (ch != ':')
824 continue;
825
826 /*
827 * "$Id: ... "; scan up to the closing dollar sign and discard.
828 */
829 while (size) {
830 ch = *cp++;
831 size--;
832 if (ch == '$') {
833 cnt++;
834 break;
835 }
836 if (ch == '\n')
837 break;
838 }
839 }
840 return cnt;
841 }
842
843 static int ident_to_git(const char *path, const char *src, size_t len,
844 struct strbuf *buf, int ident)
845 {
846 char *dst, *dollar;
847
848 if (!ident || (src && !count_ident(src, len)))
849 return 0;
850
851 if (!buf)
852 return 1;
853
854 /* only grow if not in place */
855 if (strbuf_avail(buf) + buf->len < len)
856 strbuf_grow(buf, len - buf->len);
857 dst = buf->buf;
858 for (;;) {
859 dollar = memchr(src, '$', len);
860 if (!dollar)
861 break;
862 memmove(dst, src, dollar + 1 - src);
863 dst += dollar + 1 - src;
864 len -= dollar + 1 - src;
865 src = dollar + 1;
866
867 if (len > 3 && !memcmp(src, "Id:", 3)) {
868 dollar = memchr(src + 3, '$', len - 3);
869 if (!dollar)
870 break;
871 if (memchr(src + 3, '\n', dollar - src - 3)) {
872 /* Line break before the next dollar. */
873 continue;
874 }
875
876 memcpy(dst, "Id$", 3);
877 dst += 3;
878 len -= dollar + 1 - src;
879 src = dollar + 1;
880 }
881 }
882 memmove(dst, src, len);
883 strbuf_setlen(buf, dst + len - buf->buf);
884 return 1;
885 }
886
887 static int ident_to_worktree(const char *path, const char *src, size_t len,
888 struct strbuf *buf, int ident)
889 {
890 unsigned char sha1[20];
891 char *to_free = NULL, *dollar, *spc;
892 int cnt;
893
894 if (!ident)
895 return 0;
896
897 cnt = count_ident(src, len);
898 if (!cnt)
899 return 0;
900
901 /* are we "faking" in place editing ? */
902 if (src == buf->buf)
903 to_free = strbuf_detach(buf, NULL);
904 hash_sha1_file(src, len, "blob", sha1);
905
906 strbuf_grow(buf, len + cnt * 43);
907 for (;;) {
908 /* step 1: run to the next '$' */
909 dollar = memchr(src, '$', len);
910 if (!dollar)
911 break;
912 strbuf_add(buf, src, dollar + 1 - src);
913 len -= dollar + 1 - src;
914 src = dollar + 1;
915
916 /* step 2: does it looks like a bit like Id:xxx$ or Id$ ? */
917 if (len < 3 || memcmp("Id", src, 2))
918 continue;
919
920 /* step 3: skip over Id$ or Id:xxxxx$ */
921 if (src[2] == '$') {
922 src += 3;
923 len -= 3;
924 } else if (src[2] == ':') {
925 /*
926 * It's possible that an expanded Id has crept its way into the
927 * repository, we cope with that by stripping the expansion out.
928 * This is probably not a good idea, since it will cause changes
929 * on checkout, which won't go away by stash, but let's keep it
930 * for git-style ids.
931 */
932 dollar = memchr(src + 3, '$', len - 3);
933 if (!dollar) {
934 /* incomplete keyword, no more '$', so just quit the loop */
935 break;
936 }
937
938 if (memchr(src + 3, '\n', dollar - src - 3)) {
939 /* Line break before the next dollar. */
940 continue;
941 }
942
943 spc = memchr(src + 4, ' ', dollar - src - 4);
944 if (spc && spc < dollar-1) {
945 /* There are spaces in unexpected places.
946 * This is probably an id from some other
947 * versioning system. Keep it for now.
948 */
949 continue;
950 }
951
952 len -= dollar + 1 - src;
953 src = dollar + 1;
954 } else {
955 /* it wasn't a "Id$" or "Id:xxxx$" */
956 continue;
957 }
958
959 /* step 4: substitute */
960 strbuf_addstr(buf, "Id: ");
961 strbuf_add(buf, sha1_to_hex(sha1), 40);
962 strbuf_addstr(buf, " $");
963 }
964 strbuf_add(buf, src, len);
965
966 free(to_free);
967 return 1;
968 }
969
970 static enum crlf_action git_path_check_crlf(struct attr_check_item *check)
971 {
972 const char *value = check->value;
973
974 if (ATTR_TRUE(value))
975 return CRLF_TEXT;
976 else if (ATTR_FALSE(value))
977 return CRLF_BINARY;
978 else if (ATTR_UNSET(value))
979 ;
980 else if (!strcmp(value, "input"))
981 return CRLF_TEXT_INPUT;
982 else if (!strcmp(value, "auto"))
983 return CRLF_AUTO;
984 return CRLF_UNDEFINED;
985 }
986
987 static enum eol git_path_check_eol(struct attr_check_item *check)
988 {
989 const char *value = check->value;
990
991 if (ATTR_UNSET(value))
992 ;
993 else if (!strcmp(value, "lf"))
994 return EOL_LF;
995 else if (!strcmp(value, "crlf"))
996 return EOL_CRLF;
997 return EOL_UNSET;
998 }
999
1000 static struct convert_driver *git_path_check_convert(struct attr_check_item *check)
1001 {
1002 const char *value = check->value;
1003 struct convert_driver *drv;
1004
1005 if (ATTR_TRUE(value) || ATTR_FALSE(value) || ATTR_UNSET(value))
1006 return NULL;
1007 for (drv = user_convert; drv; drv = drv->next)
1008 if (!strcmp(value, drv->name))
1009 return drv;
1010 return NULL;
1011 }
1012
1013 static int git_path_check_ident(struct attr_check_item *check)
1014 {
1015 const char *value = check->value;
1016
1017 return !!ATTR_TRUE(value);
1018 }
1019
1020 struct conv_attrs {
1021 struct convert_driver *drv;
1022 enum crlf_action attr_action; /* What attr says */
1023 enum crlf_action crlf_action; /* When no attr is set, use core.autocrlf */
1024 int ident;
1025 };
1026
1027 static void convert_attrs(struct conv_attrs *ca, const char *path)
1028 {
1029 static struct attr_check *check;
1030
1031 if (!check) {
1032 check = attr_check_initl("crlf", "ident", "filter",
1033 "eol", "text", NULL);
1034 user_convert_tail = &user_convert;
1035 git_config(read_convert_config, NULL);
1036 }
1037
1038 if (!git_check_attr(path, check)) {
1039 struct attr_check_item *ccheck = check->items;
1040 ca->crlf_action = git_path_check_crlf(ccheck + 4);
1041 if (ca->crlf_action == CRLF_UNDEFINED)
1042 ca->crlf_action = git_path_check_crlf(ccheck + 0);
1043 ca->attr_action = ca->crlf_action;
1044 ca->ident = git_path_check_ident(ccheck + 1);
1045 ca->drv = git_path_check_convert(ccheck + 2);
1046 if (ca->crlf_action != CRLF_BINARY) {
1047 enum eol eol_attr = git_path_check_eol(ccheck + 3);
1048 if (ca->crlf_action == CRLF_AUTO && eol_attr == EOL_LF)
1049 ca->crlf_action = CRLF_AUTO_INPUT;
1050 else if (ca->crlf_action == CRLF_AUTO && eol_attr == EOL_CRLF)
1051 ca->crlf_action = CRLF_AUTO_CRLF;
1052 else if (eol_attr == EOL_LF)
1053 ca->crlf_action = CRLF_TEXT_INPUT;
1054 else if (eol_attr == EOL_CRLF)
1055 ca->crlf_action = CRLF_TEXT_CRLF;
1056 }
1057 ca->attr_action = ca->crlf_action;
1058 } else {
1059 ca->drv = NULL;
1060 ca->crlf_action = CRLF_UNDEFINED;
1061 ca->ident = 0;
1062 }
1063 if (ca->crlf_action == CRLF_TEXT)
1064 ca->crlf_action = text_eol_is_crlf() ? CRLF_TEXT_CRLF : CRLF_TEXT_INPUT;
1065 if (ca->crlf_action == CRLF_UNDEFINED && auto_crlf == AUTO_CRLF_FALSE)
1066 ca->crlf_action = CRLF_BINARY;
1067 if (ca->crlf_action == CRLF_UNDEFINED && auto_crlf == AUTO_CRLF_TRUE)
1068 ca->crlf_action = CRLF_AUTO_CRLF;
1069 if (ca->crlf_action == CRLF_UNDEFINED && auto_crlf == AUTO_CRLF_INPUT)
1070 ca->crlf_action = CRLF_AUTO_INPUT;
1071 }
1072
1073 int would_convert_to_git_filter_fd(const char *path)
1074 {
1075 struct conv_attrs ca;
1076
1077 convert_attrs(&ca, path);
1078 if (!ca.drv)
1079 return 0;
1080
1081 /*
1082 * Apply a filter to an fd only if the filter is required to succeed.
1083 * We must die if the filter fails, because the original data before
1084 * filtering is not available.
1085 */
1086 if (!ca.drv->required)
1087 return 0;
1088
1089 return apply_filter(path, NULL, 0, -1, NULL, ca.drv, CAP_CLEAN, NULL);
1090 }
1091
1092 const char *get_convert_attr_ascii(const char *path)
1093 {
1094 struct conv_attrs ca;
1095
1096 convert_attrs(&ca, path);
1097 switch (ca.attr_action) {
1098 case CRLF_UNDEFINED:
1099 return "";
1100 case CRLF_BINARY:
1101 return "-text";
1102 case CRLF_TEXT:
1103 return "text";
1104 case CRLF_TEXT_INPUT:
1105 return "text eol=lf";
1106 case CRLF_TEXT_CRLF:
1107 return "text eol=crlf";
1108 case CRLF_AUTO:
1109 return "text=auto";
1110 case CRLF_AUTO_CRLF:
1111 return "text=auto eol=crlf";
1112 case CRLF_AUTO_INPUT:
1113 return "text=auto eol=lf";
1114 }
1115 return "";
1116 }
1117
1118 int convert_to_git(const struct index_state *istate,
1119 const char *path, const char *src, size_t len,
1120 struct strbuf *dst, enum safe_crlf checksafe)
1121 {
1122 int ret = 0;
1123 struct conv_attrs ca;
1124
1125 convert_attrs(&ca, path);
1126
1127 ret |= apply_filter(path, src, len, -1, dst, ca.drv, CAP_CLEAN, NULL);
1128 if (!ret && ca.drv && ca.drv->required)
1129 die("%s: clean filter '%s' failed", path, ca.drv->name);
1130
1131 if (ret && dst) {
1132 src = dst->buf;
1133 len = dst->len;
1134 }
1135 if (checksafe != SAFE_CRLF_KEEP_CRLF) {
1136 ret |= crlf_to_git(istate, path, src, len, dst, ca.crlf_action, checksafe);
1137 if (ret && dst) {
1138 src = dst->buf;
1139 len = dst->len;
1140 }
1141 }
1142 return ret | ident_to_git(path, src, len, dst, ca.ident);
1143 }
1144
1145 void convert_to_git_filter_fd(const struct index_state *istate,
1146 const char *path, int fd, struct strbuf *dst,
1147 enum safe_crlf checksafe)
1148 {
1149 struct conv_attrs ca;
1150 convert_attrs(&ca, path);
1151
1152 assert(ca.drv);
1153 assert(ca.drv->clean || ca.drv->process);
1154
1155 if (!apply_filter(path, NULL, 0, fd, dst, ca.drv, CAP_CLEAN, NULL))
1156 die("%s: clean filter '%s' failed", path, ca.drv->name);
1157
1158 crlf_to_git(istate, path, dst->buf, dst->len, dst, ca.crlf_action, checksafe);
1159 ident_to_git(path, dst->buf, dst->len, dst, ca.ident);
1160 }
1161
1162 static int convert_to_working_tree_internal(const char *path, const char *src,
1163 size_t len, struct strbuf *dst,
1164 int normalizing, struct delayed_checkout *dco)
1165 {
1166 int ret = 0, ret_filter = 0;
1167 struct conv_attrs ca;
1168
1169 convert_attrs(&ca, path);
1170
1171 ret |= ident_to_worktree(path, src, len, dst, ca.ident);
1172 if (ret) {
1173 src = dst->buf;
1174 len = dst->len;
1175 }
1176 /*
1177 * CRLF conversion can be skipped if normalizing, unless there
1178 * is a smudge or process filter (even if the process filter doesn't
1179 * support smudge). The filters might expect CRLFs.
1180 */
1181 if ((ca.drv && (ca.drv->smudge || ca.drv->process)) || !normalizing) {
1182 ret |= crlf_to_worktree(path, src, len, dst, ca.crlf_action);
1183 if (ret) {
1184 src = dst->buf;
1185 len = dst->len;
1186 }
1187 }
1188
1189 ret_filter = apply_filter(
1190 path, src, len, -1, dst, ca.drv, CAP_SMUDGE, dco);
1191 if (!ret_filter && ca.drv && ca.drv->required)
1192 die("%s: smudge filter %s failed", path, ca.drv->name);
1193
1194 return ret | ret_filter;
1195 }
1196
1197 int async_convert_to_working_tree(const char *path, const char *src,
1198 size_t len, struct strbuf *dst,
1199 void *dco)
1200 {
1201 return convert_to_working_tree_internal(path, src, len, dst, 0, dco);
1202 }
1203
1204 int convert_to_working_tree(const char *path, const char *src, size_t len, struct strbuf *dst)
1205 {
1206 return convert_to_working_tree_internal(path, src, len, dst, 0, NULL);
1207 }
1208
1209 int renormalize_buffer(const struct index_state *istate, const char *path,
1210 const char *src, size_t len, struct strbuf *dst)
1211 {
1212 int ret = convert_to_working_tree_internal(path, src, len, dst, 1, NULL);
1213 if (ret) {
1214 src = dst->buf;
1215 len = dst->len;
1216 }
1217 return ret | convert_to_git(istate, path, src, len, dst, SAFE_CRLF_RENORMALIZE);
1218 }
1219
1220 /*****************************************************************
1221 *
1222 * Streaming conversion support
1223 *
1224 *****************************************************************/
1225
1226 typedef int (*filter_fn)(struct stream_filter *,
1227 const char *input, size_t *isize_p,
1228 char *output, size_t *osize_p);
1229 typedef void (*free_fn)(struct stream_filter *);
1230
1231 struct stream_filter_vtbl {
1232 filter_fn filter;
1233 free_fn free;
1234 };
1235
1236 struct stream_filter {
1237 struct stream_filter_vtbl *vtbl;
1238 };
1239
1240 static int null_filter_fn(struct stream_filter *filter,
1241 const char *input, size_t *isize_p,
1242 char *output, size_t *osize_p)
1243 {
1244 size_t count;
1245
1246 if (!input)
1247 return 0; /* we do not keep any states */
1248 count = *isize_p;
1249 if (*osize_p < count)
1250 count = *osize_p;
1251 if (count) {
1252 memmove(output, input, count);
1253 *isize_p -= count;
1254 *osize_p -= count;
1255 }
1256 return 0;
1257 }
1258
1259 static void null_free_fn(struct stream_filter *filter)
1260 {
1261 ; /* nothing -- null instances are shared */
1262 }
1263
1264 static struct stream_filter_vtbl null_vtbl = {
1265 null_filter_fn,
1266 null_free_fn,
1267 };
1268
1269 static struct stream_filter null_filter_singleton = {
1270 &null_vtbl,
1271 };
1272
1273 int is_null_stream_filter(struct stream_filter *filter)
1274 {
1275 return filter == &null_filter_singleton;
1276 }
1277
1278
1279 /*
1280 * LF-to-CRLF filter
1281 */
1282
1283 struct lf_to_crlf_filter {
1284 struct stream_filter filter;
1285 unsigned has_held:1;
1286 char held;
1287 };
1288
1289 static int lf_to_crlf_filter_fn(struct stream_filter *filter,
1290 const char *input, size_t *isize_p,
1291 char *output, size_t *osize_p)
1292 {
1293 size_t count, o = 0;
1294 struct lf_to_crlf_filter *lf_to_crlf = (struct lf_to_crlf_filter *)filter;
1295
1296 /*
1297 * We may be holding onto the CR to see if it is followed by a
1298 * LF, in which case we would need to go to the main loop.
1299 * Otherwise, just emit it to the output stream.
1300 */
1301 if (lf_to_crlf->has_held && (lf_to_crlf->held != '\r' || !input)) {
1302 output[o++] = lf_to_crlf->held;
1303 lf_to_crlf->has_held = 0;
1304 }
1305
1306 /* We are told to drain */
1307 if (!input) {
1308 *osize_p -= o;
1309 return 0;
1310 }
1311
1312 count = *isize_p;
1313 if (count || lf_to_crlf->has_held) {
1314 size_t i;
1315 int was_cr = 0;
1316
1317 if (lf_to_crlf->has_held) {
1318 was_cr = 1;
1319 lf_to_crlf->has_held = 0;
1320 }
1321
1322 for (i = 0; o < *osize_p && i < count; i++) {
1323 char ch = input[i];
1324
1325 if (ch == '\n') {
1326 output[o++] = '\r';
1327 } else if (was_cr) {
1328 /*
1329 * Previous round saw CR and it is not followed
1330 * by a LF; emit the CR before processing the
1331 * current character.
1332 */
1333 output[o++] = '\r';
1334 }
1335
1336 /*
1337 * We may have consumed the last output slot,
1338 * in which case we need to break out of this
1339 * loop; hold the current character before
1340 * returning.
1341 */
1342 if (*osize_p <= o) {
1343 lf_to_crlf->has_held = 1;
1344 lf_to_crlf->held = ch;
1345 continue; /* break but increment i */
1346 }
1347
1348 if (ch == '\r') {
1349 was_cr = 1;
1350 continue;
1351 }
1352
1353 was_cr = 0;
1354 output[o++] = ch;
1355 }
1356
1357 *osize_p -= o;
1358 *isize_p -= i;
1359
1360 if (!lf_to_crlf->has_held && was_cr) {
1361 lf_to_crlf->has_held = 1;
1362 lf_to_crlf->held = '\r';
1363 }
1364 }
1365 return 0;
1366 }
1367
1368 static void lf_to_crlf_free_fn(struct stream_filter *filter)
1369 {
1370 free(filter);
1371 }
1372
1373 static struct stream_filter_vtbl lf_to_crlf_vtbl = {
1374 lf_to_crlf_filter_fn,
1375 lf_to_crlf_free_fn,
1376 };
1377
1378 static struct stream_filter *lf_to_crlf_filter(void)
1379 {
1380 struct lf_to_crlf_filter *lf_to_crlf = xcalloc(1, sizeof(*lf_to_crlf));
1381
1382 lf_to_crlf->filter.vtbl = &lf_to_crlf_vtbl;
1383 return (struct stream_filter *)lf_to_crlf;
1384 }
1385
1386 /*
1387 * Cascade filter
1388 */
1389 #define FILTER_BUFFER 1024
1390 struct cascade_filter {
1391 struct stream_filter filter;
1392 struct stream_filter *one;
1393 struct stream_filter *two;
1394 char buf[FILTER_BUFFER];
1395 int end, ptr;
1396 };
1397
1398 static int cascade_filter_fn(struct stream_filter *filter,
1399 const char *input, size_t *isize_p,
1400 char *output, size_t *osize_p)
1401 {
1402 struct cascade_filter *cas = (struct cascade_filter *) filter;
1403 size_t filled = 0;
1404 size_t sz = *osize_p;
1405 size_t to_feed, remaining;
1406
1407 /*
1408 * input -- (one) --> buf -- (two) --> output
1409 */
1410 while (filled < sz) {
1411 remaining = sz - filled;
1412
1413 /* do we already have something to feed two with? */
1414 if (cas->ptr < cas->end) {
1415 to_feed = cas->end - cas->ptr;
1416 if (stream_filter(cas->two,
1417 cas->buf + cas->ptr, &to_feed,
1418 output + filled, &remaining))
1419 return -1;
1420 cas->ptr += (cas->end - cas->ptr) - to_feed;
1421 filled = sz - remaining;
1422 continue;
1423 }
1424
1425 /* feed one from upstream and have it emit into our buffer */
1426 to_feed = input ? *isize_p : 0;
1427 if (input && !to_feed)
1428 break;
1429 remaining = sizeof(cas->buf);
1430 if (stream_filter(cas->one,
1431 input, &to_feed,
1432 cas->buf, &remaining))
1433 return -1;
1434 cas->end = sizeof(cas->buf) - remaining;
1435 cas->ptr = 0;
1436 if (input) {
1437 size_t fed = *isize_p - to_feed;
1438 *isize_p -= fed;
1439 input += fed;
1440 }
1441
1442 /* do we know that we drained one completely? */
1443 if (input || cas->end)
1444 continue;
1445
1446 /* tell two to drain; we have nothing more to give it */
1447 to_feed = 0;
1448 remaining = sz - filled;
1449 if (stream_filter(cas->two,
1450 NULL, &to_feed,
1451 output + filled, &remaining))
1452 return -1;
1453 if (remaining == (sz - filled))
1454 break; /* completely drained two */
1455 filled = sz - remaining;
1456 }
1457 *osize_p -= filled;
1458 return 0;
1459 }
1460
1461 static void cascade_free_fn(struct stream_filter *filter)
1462 {
1463 struct cascade_filter *cas = (struct cascade_filter *)filter;
1464 free_stream_filter(cas->one);
1465 free_stream_filter(cas->two);
1466 free(filter);
1467 }
1468
1469 static struct stream_filter_vtbl cascade_vtbl = {
1470 cascade_filter_fn,
1471 cascade_free_fn,
1472 };
1473
1474 static struct stream_filter *cascade_filter(struct stream_filter *one,
1475 struct stream_filter *two)
1476 {
1477 struct cascade_filter *cascade;
1478
1479 if (!one || is_null_stream_filter(one))
1480 return two;
1481 if (!two || is_null_stream_filter(two))
1482 return one;
1483
1484 cascade = xmalloc(sizeof(*cascade));
1485 cascade->one = one;
1486 cascade->two = two;
1487 cascade->end = cascade->ptr = 0;
1488 cascade->filter.vtbl = &cascade_vtbl;
1489 return (struct stream_filter *)cascade;
1490 }
1491
1492 /*
1493 * ident filter
1494 */
1495 #define IDENT_DRAINING (-1)
1496 #define IDENT_SKIPPING (-2)
1497 struct ident_filter {
1498 struct stream_filter filter;
1499 struct strbuf left;
1500 int state;
1501 char ident[45]; /* ": x40 $" */
1502 };
1503
1504 static int is_foreign_ident(const char *str)
1505 {
1506 int i;
1507
1508 if (!skip_prefix(str, "$Id: ", &str))
1509 return 0;
1510 for (i = 0; str[i]; i++) {
1511 if (isspace(str[i]) && str[i+1] != '$')
1512 return 1;
1513 }
1514 return 0;
1515 }
1516
1517 static void ident_drain(struct ident_filter *ident, char **output_p, size_t *osize_p)
1518 {
1519 size_t to_drain = ident->left.len;
1520
1521 if (*osize_p < to_drain)
1522 to_drain = *osize_p;
1523 if (to_drain) {
1524 memcpy(*output_p, ident->left.buf, to_drain);
1525 strbuf_remove(&ident->left, 0, to_drain);
1526 *output_p += to_drain;
1527 *osize_p -= to_drain;
1528 }
1529 if (!ident->left.len)
1530 ident->state = 0;
1531 }
1532
1533 static int ident_filter_fn(struct stream_filter *filter,
1534 const char *input, size_t *isize_p,
1535 char *output, size_t *osize_p)
1536 {
1537 struct ident_filter *ident = (struct ident_filter *)filter;
1538 static const char head[] = "$Id";
1539
1540 if (!input) {
1541 /* drain upon eof */
1542 switch (ident->state) {
1543 default:
1544 strbuf_add(&ident->left, head, ident->state);
1545 case IDENT_SKIPPING:
1546 /* fallthru */
1547 case IDENT_DRAINING:
1548 ident_drain(ident, &output, osize_p);
1549 }
1550 return 0;
1551 }
1552
1553 while (*isize_p || (ident->state == IDENT_DRAINING)) {
1554 int ch;
1555
1556 if (ident->state == IDENT_DRAINING) {
1557 ident_drain(ident, &output, osize_p);
1558 if (!*osize_p)
1559 break;
1560 continue;
1561 }
1562
1563 ch = *(input++);
1564 (*isize_p)--;
1565
1566 if (ident->state == IDENT_SKIPPING) {
1567 /*
1568 * Skipping until '$' or LF, but keeping them
1569 * in case it is a foreign ident.
1570 */
1571 strbuf_addch(&ident->left, ch);
1572 if (ch != '\n' && ch != '$')
1573 continue;
1574 if (ch == '$' && !is_foreign_ident(ident->left.buf)) {
1575 strbuf_setlen(&ident->left, sizeof(head) - 1);
1576 strbuf_addstr(&ident->left, ident->ident);
1577 }
1578 ident->state = IDENT_DRAINING;
1579 continue;
1580 }
1581
1582 if (ident->state < sizeof(head) &&
1583 head[ident->state] == ch) {
1584 ident->state++;
1585 continue;
1586 }
1587
1588 if (ident->state)
1589 strbuf_add(&ident->left, head, ident->state);
1590 if (ident->state == sizeof(head) - 1) {
1591 if (ch != ':' && ch != '$') {
1592 strbuf_addch(&ident->left, ch);
1593 ident->state = 0;
1594 continue;
1595 }
1596
1597 if (ch == ':') {
1598 strbuf_addch(&ident->left, ch);
1599 ident->state = IDENT_SKIPPING;
1600 } else {
1601 strbuf_addstr(&ident->left, ident->ident);
1602 ident->state = IDENT_DRAINING;
1603 }
1604 continue;
1605 }
1606
1607 strbuf_addch(&ident->left, ch);
1608 ident->state = IDENT_DRAINING;
1609 }
1610 return 0;
1611 }
1612
1613 static void ident_free_fn(struct stream_filter *filter)
1614 {
1615 struct ident_filter *ident = (struct ident_filter *)filter;
1616 strbuf_release(&ident->left);
1617 free(filter);
1618 }
1619
1620 static struct stream_filter_vtbl ident_vtbl = {
1621 ident_filter_fn,
1622 ident_free_fn,
1623 };
1624
1625 static struct stream_filter *ident_filter(const unsigned char *sha1)
1626 {
1627 struct ident_filter *ident = xmalloc(sizeof(*ident));
1628
1629 xsnprintf(ident->ident, sizeof(ident->ident),
1630 ": %s $", sha1_to_hex(sha1));
1631 strbuf_init(&ident->left, 0);
1632 ident->filter.vtbl = &ident_vtbl;
1633 ident->state = 0;
1634 return (struct stream_filter *)ident;
1635 }
1636
1637 /*
1638 * Return an appropriately constructed filter for the path, or NULL if
1639 * the contents cannot be filtered without reading the whole thing
1640 * in-core.
1641 *
1642 * Note that you would be crazy to set CRLF, smuge/clean or ident to a
1643 * large binary blob you would want us not to slurp into the memory!
1644 */
1645 struct stream_filter *get_stream_filter(const char *path, const unsigned char *sha1)
1646 {
1647 struct conv_attrs ca;
1648 struct stream_filter *filter = NULL;
1649
1650 convert_attrs(&ca, path);
1651 if (ca.drv && (ca.drv->process || ca.drv->smudge || ca.drv->clean))
1652 return NULL;
1653
1654 if (ca.crlf_action == CRLF_AUTO || ca.crlf_action == CRLF_AUTO_CRLF)
1655 return NULL;
1656
1657 if (ca.ident)
1658 filter = ident_filter(sha1);
1659
1660 if (output_eol(ca.crlf_action) == EOL_CRLF)
1661 filter = cascade_filter(filter, lf_to_crlf_filter());
1662 else
1663 filter = cascade_filter(filter, &null_filter_singleton);
1664
1665 return filter;
1666 }
1667
1668 void free_stream_filter(struct stream_filter *filter)
1669 {
1670 filter->vtbl->free(filter);
1671 }
1672
1673 int stream_filter(struct stream_filter *filter,
1674 const char *input, size_t *isize_p,
1675 char *output, size_t *osize_p)
1676 {
1677 return filter->vtbl->filter(filter, input, isize_p, output, osize_p);
1678 }