Merge branch 'tg/stash-refresh-index'
[git] / builtin / am.c
1 /*
2  * Builtin "git am"
3  *
4  * Based on git-am.sh by Junio C Hamano.
5  */
6 #define USE_THE_INDEX_COMPATIBILITY_MACROS
7 #include "cache.h"
8 #include "config.h"
9 #include "builtin.h"
10 #include "exec-cmd.h"
11 #include "parse-options.h"
12 #include "dir.h"
13 #include "run-command.h"
14 #include "quote.h"
15 #include "tempfile.h"
16 #include "lockfile.h"
17 #include "cache-tree.h"
18 #include "refs.h"
19 #include "commit.h"
20 #include "diff.h"
21 #include "diffcore.h"
22 #include "unpack-trees.h"
23 #include "branch.h"
24 #include "sequencer.h"
25 #include "revision.h"
26 #include "merge-recursive.h"
27 #include "log-tree.h"
28 #include "notes-utils.h"
29 #include "rerere.h"
30 #include "prompt.h"
31 #include "mailinfo.h"
32 #include "apply.h"
33 #include "string-list.h"
34 #include "packfile.h"
35 #include "repository.h"
36
37 /**
38  * Returns the length of the first line of msg.
39  */
40 static int linelen(const char *msg)
41 {
42         return strchrnul(msg, '\n') - msg;
43 }
44
45 /**
46  * Returns true if `str` consists of only whitespace, false otherwise.
47  */
48 static int str_isspace(const char *str)
49 {
50         for (; *str; str++)
51                 if (!isspace(*str))
52                         return 0;
53
54         return 1;
55 }
56
57 enum patch_format {
58         PATCH_FORMAT_UNKNOWN = 0,
59         PATCH_FORMAT_MBOX,
60         PATCH_FORMAT_STGIT,
61         PATCH_FORMAT_STGIT_SERIES,
62         PATCH_FORMAT_HG,
63         PATCH_FORMAT_MBOXRD
64 };
65
66 enum keep_type {
67         KEEP_FALSE = 0,
68         KEEP_TRUE,      /* pass -k flag to git-mailinfo */
69         KEEP_NON_PATCH  /* pass -b flag to git-mailinfo */
70 };
71
72 enum scissors_type {
73         SCISSORS_UNSET = -1,
74         SCISSORS_FALSE = 0,  /* pass --no-scissors to git-mailinfo */
75         SCISSORS_TRUE        /* pass --scissors to git-mailinfo */
76 };
77
78 enum signoff_type {
79         SIGNOFF_FALSE = 0,
80         SIGNOFF_TRUE = 1,
81         SIGNOFF_EXPLICIT /* --signoff was set on the command-line */
82 };
83
84 struct am_state {
85         /* state directory path */
86         char *dir;
87
88         /* current and last patch numbers, 1-indexed */
89         int cur;
90         int last;
91
92         /* commit metadata and message */
93         char *author_name;
94         char *author_email;
95         char *author_date;
96         char *msg;
97         size_t msg_len;
98
99         /* when --rebasing, records the original commit the patch came from */
100         struct object_id orig_commit;
101
102         /* number of digits in patch filename */
103         int prec;
104
105         /* various operating modes and command line options */
106         int interactive;
107         int threeway;
108         int quiet;
109         int signoff; /* enum signoff_type */
110         int utf8;
111         int keep; /* enum keep_type */
112         int message_id;
113         int scissors; /* enum scissors_type */
114         struct argv_array git_apply_opts;
115         const char *resolvemsg;
116         int committer_date_is_author_date;
117         int ignore_date;
118         int allow_rerere_autoupdate;
119         const char *sign_commit;
120         int rebasing;
121 };
122
123 /**
124  * Initializes am_state with the default values.
125  */
126 static void am_state_init(struct am_state *state)
127 {
128         int gpgsign;
129
130         memset(state, 0, sizeof(*state));
131
132         state->dir = git_pathdup("rebase-apply");
133
134         state->prec = 4;
135
136         git_config_get_bool("am.threeway", &state->threeway);
137
138         state->utf8 = 1;
139
140         git_config_get_bool("am.messageid", &state->message_id);
141
142         state->scissors = SCISSORS_UNSET;
143
144         argv_array_init(&state->git_apply_opts);
145
146         if (!git_config_get_bool("commit.gpgsign", &gpgsign))
147                 state->sign_commit = gpgsign ? "" : NULL;
148 }
149
150 /**
151  * Releases memory allocated by an am_state.
152  */
153 static void am_state_release(struct am_state *state)
154 {
155         free(state->dir);
156         free(state->author_name);
157         free(state->author_email);
158         free(state->author_date);
159         free(state->msg);
160         argv_array_clear(&state->git_apply_opts);
161 }
162
163 /**
164  * Returns path relative to the am_state directory.
165  */
166 static inline const char *am_path(const struct am_state *state, const char *path)
167 {
168         return mkpath("%s/%s", state->dir, path);
169 }
170
171 /**
172  * For convenience to call write_file()
173  */
174 static void write_state_text(const struct am_state *state,
175                              const char *name, const char *string)
176 {
177         write_file(am_path(state, name), "%s", string);
178 }
179
180 static void write_state_count(const struct am_state *state,
181                               const char *name, int value)
182 {
183         write_file(am_path(state, name), "%d", value);
184 }
185
186 static void write_state_bool(const struct am_state *state,
187                              const char *name, int value)
188 {
189         write_state_text(state, name, value ? "t" : "f");
190 }
191
192 /**
193  * If state->quiet is false, calls fprintf(fp, fmt, ...), and appends a newline
194  * at the end.
195  */
196 static void say(const struct am_state *state, FILE *fp, const char *fmt, ...)
197 {
198         va_list ap;
199
200         va_start(ap, fmt);
201         if (!state->quiet) {
202                 vfprintf(fp, fmt, ap);
203                 putc('\n', fp);
204         }
205         va_end(ap);
206 }
207
208 /**
209  * Returns 1 if there is an am session in progress, 0 otherwise.
210  */
211 static int am_in_progress(const struct am_state *state)
212 {
213         struct stat st;
214
215         if (lstat(state->dir, &st) < 0 || !S_ISDIR(st.st_mode))
216                 return 0;
217         if (lstat(am_path(state, "last"), &st) || !S_ISREG(st.st_mode))
218                 return 0;
219         if (lstat(am_path(state, "next"), &st) || !S_ISREG(st.st_mode))
220                 return 0;
221         return 1;
222 }
223
224 /**
225  * Reads the contents of `file` in the `state` directory into `sb`. Returns the
226  * number of bytes read on success, -1 if the file does not exist. If `trim` is
227  * set, trailing whitespace will be removed.
228  */
229 static int read_state_file(struct strbuf *sb, const struct am_state *state,
230                         const char *file, int trim)
231 {
232         strbuf_reset(sb);
233
234         if (strbuf_read_file(sb, am_path(state, file), 0) >= 0) {
235                 if (trim)
236                         strbuf_trim(sb);
237
238                 return sb->len;
239         }
240
241         if (errno == ENOENT)
242                 return -1;
243
244         die_errno(_("could not read '%s'"), am_path(state, file));
245 }
246
247 /**
248  * Reads and parses the state directory's "author-script" file, and sets
249  * state->author_name, state->author_email and state->author_date accordingly.
250  * Returns 0 on success, -1 if the file could not be parsed.
251  *
252  * The author script is of the format:
253  *
254  *      GIT_AUTHOR_NAME='$author_name'
255  *      GIT_AUTHOR_EMAIL='$author_email'
256  *      GIT_AUTHOR_DATE='$author_date'
257  *
258  * where $author_name, $author_email and $author_date are quoted. We are strict
259  * with our parsing, as the file was meant to be eval'd in the old git-am.sh
260  * script, and thus if the file differs from what this function expects, it is
261  * better to bail out than to do something that the user does not expect.
262  */
263 static int read_am_author_script(struct am_state *state)
264 {
265         const char *filename = am_path(state, "author-script");
266
267         assert(!state->author_name);
268         assert(!state->author_email);
269         assert(!state->author_date);
270
271         return read_author_script(filename, &state->author_name,
272                                   &state->author_email, &state->author_date, 1);
273 }
274
275 /**
276  * Saves state->author_name, state->author_email and state->author_date in the
277  * state directory's "author-script" file.
278  */
279 static void write_author_script(const struct am_state *state)
280 {
281         struct strbuf sb = STRBUF_INIT;
282
283         strbuf_addstr(&sb, "GIT_AUTHOR_NAME=");
284         sq_quote_buf(&sb, state->author_name);
285         strbuf_addch(&sb, '\n');
286
287         strbuf_addstr(&sb, "GIT_AUTHOR_EMAIL=");
288         sq_quote_buf(&sb, state->author_email);
289         strbuf_addch(&sb, '\n');
290
291         strbuf_addstr(&sb, "GIT_AUTHOR_DATE=");
292         sq_quote_buf(&sb, state->author_date);
293         strbuf_addch(&sb, '\n');
294
295         write_state_text(state, "author-script", sb.buf);
296
297         strbuf_release(&sb);
298 }
299
300 /**
301  * Reads the commit message from the state directory's "final-commit" file,
302  * setting state->msg to its contents and state->msg_len to the length of its
303  * contents in bytes.
304  *
305  * Returns 0 on success, -1 if the file does not exist.
306  */
307 static int read_commit_msg(struct am_state *state)
308 {
309         struct strbuf sb = STRBUF_INIT;
310
311         assert(!state->msg);
312
313         if (read_state_file(&sb, state, "final-commit", 0) < 0) {
314                 strbuf_release(&sb);
315                 return -1;
316         }
317
318         state->msg = strbuf_detach(&sb, &state->msg_len);
319         return 0;
320 }
321
322 /**
323  * Saves state->msg in the state directory's "final-commit" file.
324  */
325 static void write_commit_msg(const struct am_state *state)
326 {
327         const char *filename = am_path(state, "final-commit");
328         write_file_buf(filename, state->msg, state->msg_len);
329 }
330
331 /**
332  * Loads state from disk.
333  */
334 static void am_load(struct am_state *state)
335 {
336         struct strbuf sb = STRBUF_INIT;
337
338         if (read_state_file(&sb, state, "next", 1) < 0)
339                 BUG("state file 'next' does not exist");
340         state->cur = strtol(sb.buf, NULL, 10);
341
342         if (read_state_file(&sb, state, "last", 1) < 0)
343                 BUG("state file 'last' does not exist");
344         state->last = strtol(sb.buf, NULL, 10);
345
346         if (read_am_author_script(state) < 0)
347                 die(_("could not parse author script"));
348
349         read_commit_msg(state);
350
351         if (read_state_file(&sb, state, "original-commit", 1) < 0)
352                 oidclr(&state->orig_commit);
353         else if (get_oid_hex(sb.buf, &state->orig_commit) < 0)
354                 die(_("could not parse %s"), am_path(state, "original-commit"));
355
356         read_state_file(&sb, state, "threeway", 1);
357         state->threeway = !strcmp(sb.buf, "t");
358
359         read_state_file(&sb, state, "quiet", 1);
360         state->quiet = !strcmp(sb.buf, "t");
361
362         read_state_file(&sb, state, "sign", 1);
363         state->signoff = !strcmp(sb.buf, "t");
364
365         read_state_file(&sb, state, "utf8", 1);
366         state->utf8 = !strcmp(sb.buf, "t");
367
368         if (file_exists(am_path(state, "rerere-autoupdate"))) {
369                 read_state_file(&sb, state, "rerere-autoupdate", 1);
370                 state->allow_rerere_autoupdate = strcmp(sb.buf, "t") ?
371                         RERERE_NOAUTOUPDATE : RERERE_AUTOUPDATE;
372         } else {
373                 state->allow_rerere_autoupdate = 0;
374         }
375
376         read_state_file(&sb, state, "keep", 1);
377         if (!strcmp(sb.buf, "t"))
378                 state->keep = KEEP_TRUE;
379         else if (!strcmp(sb.buf, "b"))
380                 state->keep = KEEP_NON_PATCH;
381         else
382                 state->keep = KEEP_FALSE;
383
384         read_state_file(&sb, state, "messageid", 1);
385         state->message_id = !strcmp(sb.buf, "t");
386
387         read_state_file(&sb, state, "scissors", 1);
388         if (!strcmp(sb.buf, "t"))
389                 state->scissors = SCISSORS_TRUE;
390         else if (!strcmp(sb.buf, "f"))
391                 state->scissors = SCISSORS_FALSE;
392         else
393                 state->scissors = SCISSORS_UNSET;
394
395         read_state_file(&sb, state, "apply-opt", 1);
396         argv_array_clear(&state->git_apply_opts);
397         if (sq_dequote_to_argv_array(sb.buf, &state->git_apply_opts) < 0)
398                 die(_("could not parse %s"), am_path(state, "apply-opt"));
399
400         state->rebasing = !!file_exists(am_path(state, "rebasing"));
401
402         strbuf_release(&sb);
403 }
404
405 /**
406  * Removes the am_state directory, forcefully terminating the current am
407  * session.
408  */
409 static void am_destroy(const struct am_state *state)
410 {
411         struct strbuf sb = STRBUF_INIT;
412
413         strbuf_addstr(&sb, state->dir);
414         remove_dir_recursively(&sb, 0);
415         strbuf_release(&sb);
416 }
417
418 /**
419  * Runs applypatch-msg hook. Returns its exit code.
420  */
421 static int run_applypatch_msg_hook(struct am_state *state)
422 {
423         int ret;
424
425         assert(state->msg);
426         ret = run_hook_le(NULL, "applypatch-msg", am_path(state, "final-commit"), NULL);
427
428         if (!ret) {
429                 FREE_AND_NULL(state->msg);
430                 if (read_commit_msg(state) < 0)
431                         die(_("'%s' was deleted by the applypatch-msg hook"),
432                                 am_path(state, "final-commit"));
433         }
434
435         return ret;
436 }
437
438 /**
439  * Runs post-rewrite hook. Returns it exit code.
440  */
441 static int run_post_rewrite_hook(const struct am_state *state)
442 {
443         struct child_process cp = CHILD_PROCESS_INIT;
444         const char *hook = find_hook("post-rewrite");
445         int ret;
446
447         if (!hook)
448                 return 0;
449
450         argv_array_push(&cp.args, hook);
451         argv_array_push(&cp.args, "rebase");
452
453         cp.in = xopen(am_path(state, "rewritten"), O_RDONLY);
454         cp.stdout_to_stderr = 1;
455         cp.trace2_hook_name = "post-rewrite";
456
457         ret = run_command(&cp);
458
459         close(cp.in);
460         return ret;
461 }
462
463 /**
464  * Reads the state directory's "rewritten" file, and copies notes from the old
465  * commits listed in the file to their rewritten commits.
466  *
467  * Returns 0 on success, -1 on failure.
468  */
469 static int copy_notes_for_rebase(const struct am_state *state)
470 {
471         struct notes_rewrite_cfg *c;
472         struct strbuf sb = STRBUF_INIT;
473         const char *invalid_line = _("Malformed input line: '%s'.");
474         const char *msg = "Notes added by 'git rebase'";
475         FILE *fp;
476         int ret = 0;
477
478         assert(state->rebasing);
479
480         c = init_copy_notes_for_rewrite("rebase");
481         if (!c)
482                 return 0;
483
484         fp = xfopen(am_path(state, "rewritten"), "r");
485
486         while (!strbuf_getline_lf(&sb, fp)) {
487                 struct object_id from_obj, to_obj;
488                 const char *p;
489
490                 if (sb.len != the_hash_algo->hexsz * 2 + 1) {
491                         ret = error(invalid_line, sb.buf);
492                         goto finish;
493                 }
494
495                 if (parse_oid_hex(sb.buf, &from_obj, &p)) {
496                         ret = error(invalid_line, sb.buf);
497                         goto finish;
498                 }
499
500                 if (*p != ' ') {
501                         ret = error(invalid_line, sb.buf);
502                         goto finish;
503                 }
504
505                 if (get_oid_hex(p + 1, &to_obj)) {
506                         ret = error(invalid_line, sb.buf);
507                         goto finish;
508                 }
509
510                 if (copy_note_for_rewrite(c, &from_obj, &to_obj))
511                         ret = error(_("Failed to copy notes from '%s' to '%s'"),
512                                         oid_to_hex(&from_obj), oid_to_hex(&to_obj));
513         }
514
515 finish:
516         finish_copy_notes_for_rewrite(the_repository, c, msg);
517         fclose(fp);
518         strbuf_release(&sb);
519         return ret;
520 }
521
522 /**
523  * Determines if the file looks like a piece of RFC2822 mail by grabbing all
524  * non-indented lines and checking if they look like they begin with valid
525  * header field names.
526  *
527  * Returns 1 if the file looks like a piece of mail, 0 otherwise.
528  */
529 static int is_mail(FILE *fp)
530 {
531         const char *header_regex = "^[!-9;-~]+:";
532         struct strbuf sb = STRBUF_INIT;
533         regex_t regex;
534         int ret = 1;
535
536         if (fseek(fp, 0L, SEEK_SET))
537                 die_errno(_("fseek failed"));
538
539         if (regcomp(&regex, header_regex, REG_NOSUB | REG_EXTENDED))
540                 die("invalid pattern: %s", header_regex);
541
542         while (!strbuf_getline(&sb, fp)) {
543                 if (!sb.len)
544                         break; /* End of header */
545
546                 /* Ignore indented folded lines */
547                 if (*sb.buf == '\t' || *sb.buf == ' ')
548                         continue;
549
550                 /* It's a header if it matches header_regex */
551                 if (regexec(&regex, sb.buf, 0, NULL, 0)) {
552                         ret = 0;
553                         goto done;
554                 }
555         }
556
557 done:
558         regfree(&regex);
559         strbuf_release(&sb);
560         return ret;
561 }
562
563 /**
564  * Attempts to detect the patch_format of the patches contained in `paths`,
565  * returning the PATCH_FORMAT_* enum value. Returns PATCH_FORMAT_UNKNOWN if
566  * detection fails.
567  */
568 static int detect_patch_format(const char **paths)
569 {
570         enum patch_format ret = PATCH_FORMAT_UNKNOWN;
571         struct strbuf l1 = STRBUF_INIT;
572         struct strbuf l2 = STRBUF_INIT;
573         struct strbuf l3 = STRBUF_INIT;
574         FILE *fp;
575
576         /*
577          * We default to mbox format if input is from stdin and for directories
578          */
579         if (!*paths || !strcmp(*paths, "-") || is_directory(*paths))
580                 return PATCH_FORMAT_MBOX;
581
582         /*
583          * Otherwise, check the first few lines of the first patch, starting
584          * from the first non-blank line, to try to detect its format.
585          */
586
587         fp = xfopen(*paths, "r");
588
589         while (!strbuf_getline(&l1, fp)) {
590                 if (l1.len)
591                         break;
592         }
593
594         if (starts_with(l1.buf, "From ") || starts_with(l1.buf, "From: ")) {
595                 ret = PATCH_FORMAT_MBOX;
596                 goto done;
597         }
598
599         if (starts_with(l1.buf, "# This series applies on GIT commit")) {
600                 ret = PATCH_FORMAT_STGIT_SERIES;
601                 goto done;
602         }
603
604         if (!strcmp(l1.buf, "# HG changeset patch")) {
605                 ret = PATCH_FORMAT_HG;
606                 goto done;
607         }
608
609         strbuf_getline(&l2, fp);
610         strbuf_getline(&l3, fp);
611
612         /*
613          * If the second line is empty and the third is a From, Author or Date
614          * entry, this is likely an StGit patch.
615          */
616         if (l1.len && !l2.len &&
617                 (starts_with(l3.buf, "From:") ||
618                  starts_with(l3.buf, "Author:") ||
619                  starts_with(l3.buf, "Date:"))) {
620                 ret = PATCH_FORMAT_STGIT;
621                 goto done;
622         }
623
624         if (l1.len && is_mail(fp)) {
625                 ret = PATCH_FORMAT_MBOX;
626                 goto done;
627         }
628
629 done:
630         fclose(fp);
631         strbuf_release(&l1);
632         strbuf_release(&l2);
633         strbuf_release(&l3);
634         return ret;
635 }
636
637 /**
638  * Splits out individual email patches from `paths`, where each path is either
639  * a mbox file or a Maildir. Returns 0 on success, -1 on failure.
640  */
641 static int split_mail_mbox(struct am_state *state, const char **paths,
642                                 int keep_cr, int mboxrd)
643 {
644         struct child_process cp = CHILD_PROCESS_INIT;
645         struct strbuf last = STRBUF_INIT;
646         int ret;
647
648         cp.git_cmd = 1;
649         argv_array_push(&cp.args, "mailsplit");
650         argv_array_pushf(&cp.args, "-d%d", state->prec);
651         argv_array_pushf(&cp.args, "-o%s", state->dir);
652         argv_array_push(&cp.args, "-b");
653         if (keep_cr)
654                 argv_array_push(&cp.args, "--keep-cr");
655         if (mboxrd)
656                 argv_array_push(&cp.args, "--mboxrd");
657         argv_array_push(&cp.args, "--");
658         argv_array_pushv(&cp.args, paths);
659
660         ret = capture_command(&cp, &last, 8);
661         if (ret)
662                 goto exit;
663
664         state->cur = 1;
665         state->last = strtol(last.buf, NULL, 10);
666
667 exit:
668         strbuf_release(&last);
669         return ret ? -1 : 0;
670 }
671
672 /**
673  * Callback signature for split_mail_conv(). The foreign patch should be
674  * read from `in`, and the converted patch (in RFC2822 mail format) should be
675  * written to `out`. Return 0 on success, or -1 on failure.
676  */
677 typedef int (*mail_conv_fn)(FILE *out, FILE *in, int keep_cr);
678
679 /**
680  * Calls `fn` for each file in `paths` to convert the foreign patch to the
681  * RFC2822 mail format suitable for parsing with git-mailinfo.
682  *
683  * Returns 0 on success, -1 on failure.
684  */
685 static int split_mail_conv(mail_conv_fn fn, struct am_state *state,
686                         const char **paths, int keep_cr)
687 {
688         static const char *stdin_only[] = {"-", NULL};
689         int i;
690
691         if (!*paths)
692                 paths = stdin_only;
693
694         for (i = 0; *paths; paths++, i++) {
695                 FILE *in, *out;
696                 const char *mail;
697                 int ret;
698
699                 if (!strcmp(*paths, "-"))
700                         in = stdin;
701                 else
702                         in = fopen(*paths, "r");
703
704                 if (!in)
705                         return error_errno(_("could not open '%s' for reading"),
706                                            *paths);
707
708                 mail = mkpath("%s/%0*d", state->dir, state->prec, i + 1);
709
710                 out = fopen(mail, "w");
711                 if (!out) {
712                         if (in != stdin)
713                                 fclose(in);
714                         return error_errno(_("could not open '%s' for writing"),
715                                            mail);
716                 }
717
718                 ret = fn(out, in, keep_cr);
719
720                 fclose(out);
721                 if (in != stdin)
722                         fclose(in);
723
724                 if (ret)
725                         return error(_("could not parse patch '%s'"), *paths);
726         }
727
728         state->cur = 1;
729         state->last = i;
730         return 0;
731 }
732
733 /**
734  * A split_mail_conv() callback that converts an StGit patch to an RFC2822
735  * message suitable for parsing with git-mailinfo.
736  */
737 static int stgit_patch_to_mail(FILE *out, FILE *in, int keep_cr)
738 {
739         struct strbuf sb = STRBUF_INIT;
740         int subject_printed = 0;
741
742         while (!strbuf_getline_lf(&sb, in)) {
743                 const char *str;
744
745                 if (str_isspace(sb.buf))
746                         continue;
747                 else if (skip_prefix(sb.buf, "Author:", &str))
748                         fprintf(out, "From:%s\n", str);
749                 else if (starts_with(sb.buf, "From") || starts_with(sb.buf, "Date"))
750                         fprintf(out, "%s\n", sb.buf);
751                 else if (!subject_printed) {
752                         fprintf(out, "Subject: %s\n", sb.buf);
753                         subject_printed = 1;
754                 } else {
755                         fprintf(out, "\n%s\n", sb.buf);
756                         break;
757                 }
758         }
759
760         strbuf_reset(&sb);
761         while (strbuf_fread(&sb, 8192, in) > 0) {
762                 fwrite(sb.buf, 1, sb.len, out);
763                 strbuf_reset(&sb);
764         }
765
766         strbuf_release(&sb);
767         return 0;
768 }
769
770 /**
771  * This function only supports a single StGit series file in `paths`.
772  *
773  * Given an StGit series file, converts the StGit patches in the series into
774  * RFC2822 messages suitable for parsing with git-mailinfo, and queues them in
775  * the state directory.
776  *
777  * Returns 0 on success, -1 on failure.
778  */
779 static int split_mail_stgit_series(struct am_state *state, const char **paths,
780                                         int keep_cr)
781 {
782         const char *series_dir;
783         char *series_dir_buf;
784         FILE *fp;
785         struct argv_array patches = ARGV_ARRAY_INIT;
786         struct strbuf sb = STRBUF_INIT;
787         int ret;
788
789         if (!paths[0] || paths[1])
790                 return error(_("Only one StGIT patch series can be applied at once"));
791
792         series_dir_buf = xstrdup(*paths);
793         series_dir = dirname(series_dir_buf);
794
795         fp = fopen(*paths, "r");
796         if (!fp)
797                 return error_errno(_("could not open '%s' for reading"), *paths);
798
799         while (!strbuf_getline_lf(&sb, fp)) {
800                 if (*sb.buf == '#')
801                         continue; /* skip comment lines */
802
803                 argv_array_push(&patches, mkpath("%s/%s", series_dir, sb.buf));
804         }
805
806         fclose(fp);
807         strbuf_release(&sb);
808         free(series_dir_buf);
809
810         ret = split_mail_conv(stgit_patch_to_mail, state, patches.argv, keep_cr);
811
812         argv_array_clear(&patches);
813         return ret;
814 }
815
816 /**
817  * A split_patches_conv() callback that converts a mercurial patch to a RFC2822
818  * message suitable for parsing with git-mailinfo.
819  */
820 static int hg_patch_to_mail(FILE *out, FILE *in, int keep_cr)
821 {
822         struct strbuf sb = STRBUF_INIT;
823         int rc = 0;
824
825         while (!strbuf_getline_lf(&sb, in)) {
826                 const char *str;
827
828                 if (skip_prefix(sb.buf, "# User ", &str))
829                         fprintf(out, "From: %s\n", str);
830                 else if (skip_prefix(sb.buf, "# Date ", &str)) {
831                         timestamp_t timestamp;
832                         long tz, tz2;
833                         char *end;
834
835                         errno = 0;
836                         timestamp = parse_timestamp(str, &end, 10);
837                         if (errno) {
838                                 rc = error(_("invalid timestamp"));
839                                 goto exit;
840                         }
841
842                         if (!skip_prefix(end, " ", &str)) {
843                                 rc = error(_("invalid Date line"));
844                                 goto exit;
845                         }
846
847                         errno = 0;
848                         tz = strtol(str, &end, 10);
849                         if (errno) {
850                                 rc = error(_("invalid timezone offset"));
851                                 goto exit;
852                         }
853
854                         if (*end) {
855                                 rc = error(_("invalid Date line"));
856                                 goto exit;
857                         }
858
859                         /*
860                          * mercurial's timezone is in seconds west of UTC,
861                          * however git's timezone is in hours + minutes east of
862                          * UTC. Convert it.
863                          */
864                         tz2 = labs(tz) / 3600 * 100 + labs(tz) % 3600 / 60;
865                         if (tz > 0)
866                                 tz2 = -tz2;
867
868                         fprintf(out, "Date: %s\n", show_date(timestamp, tz2, DATE_MODE(RFC2822)));
869                 } else if (starts_with(sb.buf, "# ")) {
870                         continue;
871                 } else {
872                         fprintf(out, "\n%s\n", sb.buf);
873                         break;
874                 }
875         }
876
877         strbuf_reset(&sb);
878         while (strbuf_fread(&sb, 8192, in) > 0) {
879                 fwrite(sb.buf, 1, sb.len, out);
880                 strbuf_reset(&sb);
881         }
882 exit:
883         strbuf_release(&sb);
884         return rc;
885 }
886
887 /**
888  * Splits a list of files/directories into individual email patches. Each path
889  * in `paths` must be a file/directory that is formatted according to
890  * `patch_format`.
891  *
892  * Once split out, the individual email patches will be stored in the state
893  * directory, with each patch's filename being its index, padded to state->prec
894  * digits.
895  *
896  * state->cur will be set to the index of the first mail, and state->last will
897  * be set to the index of the last mail.
898  *
899  * Set keep_cr to 0 to convert all lines ending with \r\n to end with \n, 1
900  * to disable this behavior, -1 to use the default configured setting.
901  *
902  * Returns 0 on success, -1 on failure.
903  */
904 static int split_mail(struct am_state *state, enum patch_format patch_format,
905                         const char **paths, int keep_cr)
906 {
907         if (keep_cr < 0) {
908                 keep_cr = 0;
909                 git_config_get_bool("am.keepcr", &keep_cr);
910         }
911
912         switch (patch_format) {
913         case PATCH_FORMAT_MBOX:
914                 return split_mail_mbox(state, paths, keep_cr, 0);
915         case PATCH_FORMAT_STGIT:
916                 return split_mail_conv(stgit_patch_to_mail, state, paths, keep_cr);
917         case PATCH_FORMAT_STGIT_SERIES:
918                 return split_mail_stgit_series(state, paths, keep_cr);
919         case PATCH_FORMAT_HG:
920                 return split_mail_conv(hg_patch_to_mail, state, paths, keep_cr);
921         case PATCH_FORMAT_MBOXRD:
922                 return split_mail_mbox(state, paths, keep_cr, 1);
923         default:
924                 BUG("invalid patch_format");
925         }
926         return -1;
927 }
928
929 /**
930  * Setup a new am session for applying patches
931  */
932 static void am_setup(struct am_state *state, enum patch_format patch_format,
933                         const char **paths, int keep_cr)
934 {
935         struct object_id curr_head;
936         const char *str;
937         struct strbuf sb = STRBUF_INIT;
938
939         if (!patch_format)
940                 patch_format = detect_patch_format(paths);
941
942         if (!patch_format) {
943                 fprintf_ln(stderr, _("Patch format detection failed."));
944                 exit(128);
945         }
946
947         if (mkdir(state->dir, 0777) < 0 && errno != EEXIST)
948                 die_errno(_("failed to create directory '%s'"), state->dir);
949         delete_ref(NULL, "REBASE_HEAD", NULL, REF_NO_DEREF);
950
951         if (split_mail(state, patch_format, paths, keep_cr) < 0) {
952                 am_destroy(state);
953                 die(_("Failed to split patches."));
954         }
955
956         if (state->rebasing)
957                 state->threeway = 1;
958
959         write_state_bool(state, "threeway", state->threeway);
960         write_state_bool(state, "quiet", state->quiet);
961         write_state_bool(state, "sign", state->signoff);
962         write_state_bool(state, "utf8", state->utf8);
963
964         if (state->allow_rerere_autoupdate)
965                 write_state_bool(state, "rerere-autoupdate",
966                          state->allow_rerere_autoupdate == RERERE_AUTOUPDATE);
967
968         switch (state->keep) {
969         case KEEP_FALSE:
970                 str = "f";
971                 break;
972         case KEEP_TRUE:
973                 str = "t";
974                 break;
975         case KEEP_NON_PATCH:
976                 str = "b";
977                 break;
978         default:
979                 BUG("invalid value for state->keep");
980         }
981
982         write_state_text(state, "keep", str);
983         write_state_bool(state, "messageid", state->message_id);
984
985         switch (state->scissors) {
986         case SCISSORS_UNSET:
987                 str = "";
988                 break;
989         case SCISSORS_FALSE:
990                 str = "f";
991                 break;
992         case SCISSORS_TRUE:
993                 str = "t";
994                 break;
995         default:
996                 BUG("invalid value for state->scissors");
997         }
998         write_state_text(state, "scissors", str);
999
1000         sq_quote_argv(&sb, state->git_apply_opts.argv);
1001         write_state_text(state, "apply-opt", sb.buf);
1002
1003         if (state->rebasing)
1004                 write_state_text(state, "rebasing", "");
1005         else
1006                 write_state_text(state, "applying", "");
1007
1008         if (!get_oid("HEAD", &curr_head)) {
1009                 write_state_text(state, "abort-safety", oid_to_hex(&curr_head));
1010                 if (!state->rebasing)
1011                         update_ref("am", "ORIG_HEAD", &curr_head, NULL, 0,
1012                                    UPDATE_REFS_DIE_ON_ERR);
1013         } else {
1014                 write_state_text(state, "abort-safety", "");
1015                 if (!state->rebasing)
1016                         delete_ref(NULL, "ORIG_HEAD", NULL, 0);
1017         }
1018
1019         /*
1020          * NOTE: Since the "next" and "last" files determine if an am_state
1021          * session is in progress, they should be written last.
1022          */
1023
1024         write_state_count(state, "next", state->cur);
1025         write_state_count(state, "last", state->last);
1026
1027         strbuf_release(&sb);
1028 }
1029
1030 /**
1031  * Increments the patch pointer, and cleans am_state for the application of the
1032  * next patch.
1033  */
1034 static void am_next(struct am_state *state)
1035 {
1036         struct object_id head;
1037
1038         FREE_AND_NULL(state->author_name);
1039         FREE_AND_NULL(state->author_email);
1040         FREE_AND_NULL(state->author_date);
1041         FREE_AND_NULL(state->msg);
1042         state->msg_len = 0;
1043
1044         unlink(am_path(state, "author-script"));
1045         unlink(am_path(state, "final-commit"));
1046
1047         oidclr(&state->orig_commit);
1048         unlink(am_path(state, "original-commit"));
1049         delete_ref(NULL, "REBASE_HEAD", NULL, REF_NO_DEREF);
1050
1051         if (!get_oid("HEAD", &head))
1052                 write_state_text(state, "abort-safety", oid_to_hex(&head));
1053         else
1054                 write_state_text(state, "abort-safety", "");
1055
1056         state->cur++;
1057         write_state_count(state, "next", state->cur);
1058 }
1059
1060 /**
1061  * Returns the filename of the current patch email.
1062  */
1063 static const char *msgnum(const struct am_state *state)
1064 {
1065         static struct strbuf sb = STRBUF_INIT;
1066
1067         strbuf_reset(&sb);
1068         strbuf_addf(&sb, "%0*d", state->prec, state->cur);
1069
1070         return sb.buf;
1071 }
1072
1073 /**
1074  * Dies with a user-friendly message on how to proceed after resolving the
1075  * problem. This message can be overridden with state->resolvemsg.
1076  */
1077 static void NORETURN die_user_resolve(const struct am_state *state)
1078 {
1079         if (state->resolvemsg) {
1080                 printf_ln("%s", state->resolvemsg);
1081         } else {
1082                 const char *cmdline = state->interactive ? "git am -i" : "git am";
1083
1084                 printf_ln(_("When you have resolved this problem, run \"%s --continue\"."), cmdline);
1085                 printf_ln(_("If you prefer to skip this patch, run \"%s --skip\" instead."), cmdline);
1086                 printf_ln(_("To restore the original branch and stop patching, run \"%s --abort\"."), cmdline);
1087         }
1088
1089         exit(128);
1090 }
1091
1092 /**
1093  * Appends signoff to the "msg" field of the am_state.
1094  */
1095 static void am_append_signoff(struct am_state *state)
1096 {
1097         struct strbuf sb = STRBUF_INIT;
1098
1099         strbuf_attach(&sb, state->msg, state->msg_len, state->msg_len);
1100         append_signoff(&sb, 0, 0);
1101         state->msg = strbuf_detach(&sb, &state->msg_len);
1102 }
1103
1104 /**
1105  * Parses `mail` using git-mailinfo, extracting its patch and authorship info.
1106  * state->msg will be set to the patch message. state->author_name,
1107  * state->author_email and state->author_date will be set to the patch author's
1108  * name, email and date respectively. The patch body will be written to the
1109  * state directory's "patch" file.
1110  *
1111  * Returns 1 if the patch should be skipped, 0 otherwise.
1112  */
1113 static int parse_mail(struct am_state *state, const char *mail)
1114 {
1115         FILE *fp;
1116         struct strbuf sb = STRBUF_INIT;
1117         struct strbuf msg = STRBUF_INIT;
1118         struct strbuf author_name = STRBUF_INIT;
1119         struct strbuf author_date = STRBUF_INIT;
1120         struct strbuf author_email = STRBUF_INIT;
1121         int ret = 0;
1122         struct mailinfo mi;
1123
1124         setup_mailinfo(&mi);
1125
1126         if (state->utf8)
1127                 mi.metainfo_charset = get_commit_output_encoding();
1128         else
1129                 mi.metainfo_charset = NULL;
1130
1131         switch (state->keep) {
1132         case KEEP_FALSE:
1133                 break;
1134         case KEEP_TRUE:
1135                 mi.keep_subject = 1;
1136                 break;
1137         case KEEP_NON_PATCH:
1138                 mi.keep_non_patch_brackets_in_subject = 1;
1139                 break;
1140         default:
1141                 BUG("invalid value for state->keep");
1142         }
1143
1144         if (state->message_id)
1145                 mi.add_message_id = 1;
1146
1147         switch (state->scissors) {
1148         case SCISSORS_UNSET:
1149                 break;
1150         case SCISSORS_FALSE:
1151                 mi.use_scissors = 0;
1152                 break;
1153         case SCISSORS_TRUE:
1154                 mi.use_scissors = 1;
1155                 break;
1156         default:
1157                 BUG("invalid value for state->scissors");
1158         }
1159
1160         mi.input = xfopen(mail, "r");
1161         mi.output = xfopen(am_path(state, "info"), "w");
1162         if (mailinfo(&mi, am_path(state, "msg"), am_path(state, "patch")))
1163                 die("could not parse patch");
1164
1165         fclose(mi.input);
1166         fclose(mi.output);
1167
1168         if (mi.format_flowed)
1169                 warning(_("Patch sent with format=flowed; "
1170                           "space at the end of lines might be lost."));
1171
1172         /* Extract message and author information */
1173         fp = xfopen(am_path(state, "info"), "r");
1174         while (!strbuf_getline_lf(&sb, fp)) {
1175                 const char *x;
1176
1177                 if (skip_prefix(sb.buf, "Subject: ", &x)) {
1178                         if (msg.len)
1179                                 strbuf_addch(&msg, '\n');
1180                         strbuf_addstr(&msg, x);
1181                 } else if (skip_prefix(sb.buf, "Author: ", &x))
1182                         strbuf_addstr(&author_name, x);
1183                 else if (skip_prefix(sb.buf, "Email: ", &x))
1184                         strbuf_addstr(&author_email, x);
1185                 else if (skip_prefix(sb.buf, "Date: ", &x))
1186                         strbuf_addstr(&author_date, x);
1187         }
1188         fclose(fp);
1189
1190         /* Skip pine's internal folder data */
1191         if (!strcmp(author_name.buf, "Mail System Internal Data")) {
1192                 ret = 1;
1193                 goto finish;
1194         }
1195
1196         if (is_empty_or_missing_file(am_path(state, "patch"))) {
1197                 printf_ln(_("Patch is empty."));
1198                 die_user_resolve(state);
1199         }
1200
1201         strbuf_addstr(&msg, "\n\n");
1202         strbuf_addbuf(&msg, &mi.log_message);
1203         strbuf_stripspace(&msg, 0);
1204
1205         assert(!state->author_name);
1206         state->author_name = strbuf_detach(&author_name, NULL);
1207
1208         assert(!state->author_email);
1209         state->author_email = strbuf_detach(&author_email, NULL);
1210
1211         assert(!state->author_date);
1212         state->author_date = strbuf_detach(&author_date, NULL);
1213
1214         assert(!state->msg);
1215         state->msg = strbuf_detach(&msg, &state->msg_len);
1216
1217 finish:
1218         strbuf_release(&msg);
1219         strbuf_release(&author_date);
1220         strbuf_release(&author_email);
1221         strbuf_release(&author_name);
1222         strbuf_release(&sb);
1223         clear_mailinfo(&mi);
1224         return ret;
1225 }
1226
1227 /**
1228  * Sets commit_id to the commit hash where the mail was generated from.
1229  * Returns 0 on success, -1 on failure.
1230  */
1231 static int get_mail_commit_oid(struct object_id *commit_id, const char *mail)
1232 {
1233         struct strbuf sb = STRBUF_INIT;
1234         FILE *fp = xfopen(mail, "r");
1235         const char *x;
1236         int ret = 0;
1237
1238         if (strbuf_getline_lf(&sb, fp) ||
1239             !skip_prefix(sb.buf, "From ", &x) ||
1240             get_oid_hex(x, commit_id) < 0)
1241                 ret = -1;
1242
1243         strbuf_release(&sb);
1244         fclose(fp);
1245         return ret;
1246 }
1247
1248 /**
1249  * Sets state->msg, state->author_name, state->author_email, state->author_date
1250  * to the commit's respective info.
1251  */
1252 static void get_commit_info(struct am_state *state, struct commit *commit)
1253 {
1254         const char *buffer, *ident_line, *msg;
1255         size_t ident_len;
1256         struct ident_split id;
1257
1258         buffer = logmsg_reencode(commit, NULL, get_commit_output_encoding());
1259
1260         ident_line = find_commit_header(buffer, "author", &ident_len);
1261         if (!ident_line)
1262                 die(_("missing author line in commit %s"),
1263                       oid_to_hex(&commit->object.oid));
1264         if (split_ident_line(&id, ident_line, ident_len) < 0)
1265                 die(_("invalid ident line: %.*s"), (int)ident_len, ident_line);
1266
1267         assert(!state->author_name);
1268         if (id.name_begin)
1269                 state->author_name =
1270                         xmemdupz(id.name_begin, id.name_end - id.name_begin);
1271         else
1272                 state->author_name = xstrdup("");
1273
1274         assert(!state->author_email);
1275         if (id.mail_begin)
1276                 state->author_email =
1277                         xmemdupz(id.mail_begin, id.mail_end - id.mail_begin);
1278         else
1279                 state->author_email = xstrdup("");
1280
1281         assert(!state->author_date);
1282         state->author_date = xstrdup(show_ident_date(&id, DATE_MODE(NORMAL)));
1283
1284         assert(!state->msg);
1285         msg = strstr(buffer, "\n\n");
1286         if (!msg)
1287                 die(_("unable to parse commit %s"), oid_to_hex(&commit->object.oid));
1288         state->msg = xstrdup(msg + 2);
1289         state->msg_len = strlen(state->msg);
1290         unuse_commit_buffer(commit, buffer);
1291 }
1292
1293 /**
1294  * Writes `commit` as a patch to the state directory's "patch" file.
1295  */
1296 static void write_commit_patch(const struct am_state *state, struct commit *commit)
1297 {
1298         struct rev_info rev_info;
1299         FILE *fp;
1300
1301         fp = xfopen(am_path(state, "patch"), "w");
1302         repo_init_revisions(the_repository, &rev_info, NULL);
1303         rev_info.diff = 1;
1304         rev_info.abbrev = 0;
1305         rev_info.disable_stdin = 1;
1306         rev_info.show_root_diff = 1;
1307         rev_info.diffopt.output_format = DIFF_FORMAT_PATCH;
1308         rev_info.no_commit_id = 1;
1309         rev_info.diffopt.flags.binary = 1;
1310         rev_info.diffopt.flags.full_index = 1;
1311         rev_info.diffopt.use_color = 0;
1312         rev_info.diffopt.file = fp;
1313         rev_info.diffopt.close_file = 1;
1314         add_pending_object(&rev_info, &commit->object, "");
1315         diff_setup_done(&rev_info.diffopt);
1316         log_tree_commit(&rev_info, commit);
1317 }
1318
1319 /**
1320  * Writes the diff of the index against HEAD as a patch to the state
1321  * directory's "patch" file.
1322  */
1323 static void write_index_patch(const struct am_state *state)
1324 {
1325         struct tree *tree;
1326         struct object_id head;
1327         struct rev_info rev_info;
1328         FILE *fp;
1329
1330         if (!get_oid("HEAD", &head)) {
1331                 struct commit *commit = lookup_commit_or_die(&head, "HEAD");
1332                 tree = get_commit_tree(commit);
1333         } else
1334                 tree = lookup_tree(the_repository,
1335                                    the_repository->hash_algo->empty_tree);
1336
1337         fp = xfopen(am_path(state, "patch"), "w");
1338         repo_init_revisions(the_repository, &rev_info, NULL);
1339         rev_info.diff = 1;
1340         rev_info.disable_stdin = 1;
1341         rev_info.no_commit_id = 1;
1342         rev_info.diffopt.output_format = DIFF_FORMAT_PATCH;
1343         rev_info.diffopt.use_color = 0;
1344         rev_info.diffopt.file = fp;
1345         rev_info.diffopt.close_file = 1;
1346         add_pending_object(&rev_info, &tree->object, "");
1347         diff_setup_done(&rev_info.diffopt);
1348         run_diff_index(&rev_info, 1);
1349 }
1350
1351 /**
1352  * Like parse_mail(), but parses the mail by looking up its commit ID
1353  * directly. This is used in --rebasing mode to bypass git-mailinfo's munging
1354  * of patches.
1355  *
1356  * state->orig_commit will be set to the original commit ID.
1357  *
1358  * Will always return 0 as the patch should never be skipped.
1359  */
1360 static int parse_mail_rebase(struct am_state *state, const char *mail)
1361 {
1362         struct commit *commit;
1363         struct object_id commit_oid;
1364
1365         if (get_mail_commit_oid(&commit_oid, mail) < 0)
1366                 die(_("could not parse %s"), mail);
1367
1368         commit = lookup_commit_or_die(&commit_oid, mail);
1369
1370         get_commit_info(state, commit);
1371
1372         write_commit_patch(state, commit);
1373
1374         oidcpy(&state->orig_commit, &commit_oid);
1375         write_state_text(state, "original-commit", oid_to_hex(&commit_oid));
1376         update_ref("am", "REBASE_HEAD", &commit_oid,
1377                    NULL, REF_NO_DEREF, UPDATE_REFS_DIE_ON_ERR);
1378
1379         return 0;
1380 }
1381
1382 /**
1383  * Applies current patch with git-apply. Returns 0 on success, -1 otherwise. If
1384  * `index_file` is not NULL, the patch will be applied to that index.
1385  */
1386 static int run_apply(const struct am_state *state, const char *index_file)
1387 {
1388         struct argv_array apply_paths = ARGV_ARRAY_INIT;
1389         struct argv_array apply_opts = ARGV_ARRAY_INIT;
1390         struct apply_state apply_state;
1391         int res, opts_left;
1392         int force_apply = 0;
1393         int options = 0;
1394
1395         if (init_apply_state(&apply_state, the_repository, NULL))
1396                 BUG("init_apply_state() failed");
1397
1398         argv_array_push(&apply_opts, "apply");
1399         argv_array_pushv(&apply_opts, state->git_apply_opts.argv);
1400
1401         opts_left = apply_parse_options(apply_opts.argc, apply_opts.argv,
1402                                         &apply_state, &force_apply, &options,
1403                                         NULL);
1404
1405         if (opts_left != 0)
1406                 die("unknown option passed through to git apply");
1407
1408         if (index_file) {
1409                 apply_state.index_file = index_file;
1410                 apply_state.cached = 1;
1411         } else
1412                 apply_state.check_index = 1;
1413
1414         /*
1415          * If we are allowed to fall back on 3-way merge, don't give false
1416          * errors during the initial attempt.
1417          */
1418         if (state->threeway && !index_file)
1419                 apply_state.apply_verbosity = verbosity_silent;
1420
1421         if (check_apply_state(&apply_state, force_apply))
1422                 BUG("check_apply_state() failed");
1423
1424         argv_array_push(&apply_paths, am_path(state, "patch"));
1425
1426         res = apply_all_patches(&apply_state, apply_paths.argc, apply_paths.argv, options);
1427
1428         argv_array_clear(&apply_paths);
1429         argv_array_clear(&apply_opts);
1430         clear_apply_state(&apply_state);
1431
1432         if (res)
1433                 return res;
1434
1435         if (index_file) {
1436                 /* Reload index as apply_all_patches() will have modified it. */
1437                 discard_cache();
1438                 read_cache_from(index_file);
1439         }
1440
1441         return 0;
1442 }
1443
1444 /**
1445  * Builds an index that contains just the blobs needed for a 3way merge.
1446  */
1447 static int build_fake_ancestor(const struct am_state *state, const char *index_file)
1448 {
1449         struct child_process cp = CHILD_PROCESS_INIT;
1450
1451         cp.git_cmd = 1;
1452         argv_array_push(&cp.args, "apply");
1453         argv_array_pushv(&cp.args, state->git_apply_opts.argv);
1454         argv_array_pushf(&cp.args, "--build-fake-ancestor=%s", index_file);
1455         argv_array_push(&cp.args, am_path(state, "patch"));
1456
1457         if (run_command(&cp))
1458                 return -1;
1459
1460         return 0;
1461 }
1462
1463 /**
1464  * Attempt a threeway merge, using index_path as the temporary index.
1465  */
1466 static int fall_back_threeway(const struct am_state *state, const char *index_path)
1467 {
1468         struct object_id orig_tree, their_tree, our_tree;
1469         const struct object_id *bases[1] = { &orig_tree };
1470         struct merge_options o;
1471         struct commit *result;
1472         char *their_tree_name;
1473
1474         if (get_oid("HEAD", &our_tree) < 0)
1475                 oidcpy(&our_tree, the_hash_algo->empty_tree);
1476
1477         if (build_fake_ancestor(state, index_path))
1478                 return error("could not build fake ancestor");
1479
1480         discard_cache();
1481         read_cache_from(index_path);
1482
1483         if (write_index_as_tree(&orig_tree, &the_index, index_path, 0, NULL))
1484                 return error(_("Repository lacks necessary blobs to fall back on 3-way merge."));
1485
1486         say(state, stdout, _("Using index info to reconstruct a base tree..."));
1487
1488         if (!state->quiet) {
1489                 /*
1490                  * List paths that needed 3-way fallback, so that the user can
1491                  * review them with extra care to spot mismerges.
1492                  */
1493                 struct rev_info rev_info;
1494
1495                 repo_init_revisions(the_repository, &rev_info, NULL);
1496                 rev_info.diffopt.output_format = DIFF_FORMAT_NAME_STATUS;
1497                 rev_info.diffopt.filter |= diff_filter_bit('A');
1498                 rev_info.diffopt.filter |= diff_filter_bit('M');
1499                 add_pending_oid(&rev_info, "HEAD", &our_tree, 0);
1500                 diff_setup_done(&rev_info.diffopt);
1501                 run_diff_index(&rev_info, 1);
1502         }
1503
1504         if (run_apply(state, index_path))
1505                 return error(_("Did you hand edit your patch?\n"
1506                                 "It does not apply to blobs recorded in its index."));
1507
1508         if (write_index_as_tree(&their_tree, &the_index, index_path, 0, NULL))
1509                 return error("could not write tree");
1510
1511         say(state, stdout, _("Falling back to patching base and 3-way merge..."));
1512
1513         discard_cache();
1514         read_cache();
1515
1516         /*
1517          * This is not so wrong. Depending on which base we picked, orig_tree
1518          * may be wildly different from ours, but their_tree has the same set of
1519          * wildly different changes in parts the patch did not touch, so
1520          * recursive ends up canceling them, saying that we reverted all those
1521          * changes.
1522          */
1523
1524         init_merge_options(&o, the_repository);
1525
1526         o.branch1 = "HEAD";
1527         their_tree_name = xstrfmt("%.*s", linelen(state->msg), state->msg);
1528         o.branch2 = their_tree_name;
1529         o.detect_directory_renames = MERGE_DIRECTORY_RENAMES_NONE;
1530
1531         if (state->quiet)
1532                 o.verbosity = 0;
1533
1534         if (merge_recursive_generic(&o, &our_tree, &their_tree, 1, bases, &result)) {
1535                 repo_rerere(the_repository, state->allow_rerere_autoupdate);
1536                 free(their_tree_name);
1537                 return error(_("Failed to merge in the changes."));
1538         }
1539
1540         free(their_tree_name);
1541         return 0;
1542 }
1543
1544 /**
1545  * Commits the current index with state->msg as the commit message and
1546  * state->author_name, state->author_email and state->author_date as the author
1547  * information.
1548  */
1549 static void do_commit(const struct am_state *state)
1550 {
1551         struct object_id tree, parent, commit;
1552         const struct object_id *old_oid;
1553         struct commit_list *parents = NULL;
1554         const char *reflog_msg, *author;
1555         struct strbuf sb = STRBUF_INIT;
1556
1557         if (run_hook_le(NULL, "pre-applypatch", NULL))
1558                 exit(1);
1559
1560         if (write_cache_as_tree(&tree, 0, NULL))
1561                 die(_("git write-tree failed to write a tree"));
1562
1563         if (!get_oid_commit("HEAD", &parent)) {
1564                 old_oid = &parent;
1565                 commit_list_insert(lookup_commit(the_repository, &parent),
1566                                    &parents);
1567         } else {
1568                 old_oid = NULL;
1569                 say(state, stderr, _("applying to an empty history"));
1570         }
1571
1572         author = fmt_ident(state->author_name, state->author_email,
1573                 WANT_AUTHOR_IDENT,
1574                         state->ignore_date ? NULL : state->author_date,
1575                         IDENT_STRICT);
1576
1577         if (state->committer_date_is_author_date)
1578                 setenv("GIT_COMMITTER_DATE",
1579                         state->ignore_date ? "" : state->author_date, 1);
1580
1581         if (commit_tree(state->msg, state->msg_len, &tree, parents, &commit,
1582                         author, state->sign_commit))
1583                 die(_("failed to write commit object"));
1584
1585         reflog_msg = getenv("GIT_REFLOG_ACTION");
1586         if (!reflog_msg)
1587                 reflog_msg = "am";
1588
1589         strbuf_addf(&sb, "%s: %.*s", reflog_msg, linelen(state->msg),
1590                         state->msg);
1591
1592         update_ref(sb.buf, "HEAD", &commit, old_oid, 0,
1593                    UPDATE_REFS_DIE_ON_ERR);
1594
1595         if (state->rebasing) {
1596                 FILE *fp = xfopen(am_path(state, "rewritten"), "a");
1597
1598                 assert(!is_null_oid(&state->orig_commit));
1599                 fprintf(fp, "%s ", oid_to_hex(&state->orig_commit));
1600                 fprintf(fp, "%s\n", oid_to_hex(&commit));
1601                 fclose(fp);
1602         }
1603
1604         run_hook_le(NULL, "post-applypatch", NULL);
1605
1606         strbuf_release(&sb);
1607 }
1608
1609 /**
1610  * Validates the am_state for resuming -- the "msg" and authorship fields must
1611  * be filled up.
1612  */
1613 static void validate_resume_state(const struct am_state *state)
1614 {
1615         if (!state->msg)
1616                 die(_("cannot resume: %s does not exist."),
1617                         am_path(state, "final-commit"));
1618
1619         if (!state->author_name || !state->author_email || !state->author_date)
1620                 die(_("cannot resume: %s does not exist."),
1621                         am_path(state, "author-script"));
1622 }
1623
1624 /**
1625  * Interactively prompt the user on whether the current patch should be
1626  * applied.
1627  *
1628  * Returns 0 if the user chooses to apply the patch, 1 if the user chooses to
1629  * skip it.
1630  */
1631 static int do_interactive(struct am_state *state)
1632 {
1633         assert(state->msg);
1634
1635         for (;;) {
1636                 char reply[64];
1637
1638                 puts(_("Commit Body is:"));
1639                 puts("--------------------------");
1640                 printf("%s", state->msg);
1641                 puts("--------------------------");
1642
1643                 /*
1644                  * TRANSLATORS: Make sure to include [y], [n], [e], [v] and [a]
1645                  * in your translation. The program will only accept English
1646                  * input at this point.
1647                  */
1648                 printf(_("Apply? [y]es/[n]o/[e]dit/[v]iew patch/[a]ccept all: "));
1649                 if (!fgets(reply, sizeof(reply), stdin))
1650                         die("unable to read from stdin; aborting");
1651
1652                 if (*reply == 'y' || *reply == 'Y') {
1653                         return 0;
1654                 } else if (*reply == 'a' || *reply == 'A') {
1655                         state->interactive = 0;
1656                         return 0;
1657                 } else if (*reply == 'n' || *reply == 'N') {
1658                         return 1;
1659                 } else if (*reply == 'e' || *reply == 'E') {
1660                         struct strbuf msg = STRBUF_INIT;
1661
1662                         if (!launch_editor(am_path(state, "final-commit"), &msg, NULL)) {
1663                                 free(state->msg);
1664                                 state->msg = strbuf_detach(&msg, &state->msg_len);
1665                         }
1666                         strbuf_release(&msg);
1667                 } else if (*reply == 'v' || *reply == 'V') {
1668                         const char *pager = git_pager(1);
1669                         struct child_process cp = CHILD_PROCESS_INIT;
1670
1671                         if (!pager)
1672                                 pager = "cat";
1673                         prepare_pager_args(&cp, pager);
1674                         argv_array_push(&cp.args, am_path(state, "patch"));
1675                         run_command(&cp);
1676                 }
1677         }
1678 }
1679
1680 /**
1681  * Applies all queued mail.
1682  *
1683  * If `resume` is true, we are "resuming". The "msg" and authorship fields, as
1684  * well as the state directory's "patch" file is used as-is for applying the
1685  * patch and committing it.
1686  */
1687 static void am_run(struct am_state *state, int resume)
1688 {
1689         const char *argv_gc_auto[] = {"gc", "--auto", NULL};
1690         struct strbuf sb = STRBUF_INIT;
1691
1692         unlink(am_path(state, "dirtyindex"));
1693
1694         if (refresh_and_write_cache(REFRESH_QUIET, 0, 0) < 0)
1695                 die(_("unable to write index file"));
1696
1697         if (repo_index_has_changes(the_repository, NULL, &sb)) {
1698                 write_state_bool(state, "dirtyindex", 1);
1699                 die(_("Dirty index: cannot apply patches (dirty: %s)"), sb.buf);
1700         }
1701
1702         strbuf_release(&sb);
1703
1704         while (state->cur <= state->last) {
1705                 const char *mail = am_path(state, msgnum(state));
1706                 int apply_status;
1707
1708                 reset_ident_date();
1709
1710                 if (!file_exists(mail))
1711                         goto next;
1712
1713                 if (resume) {
1714                         validate_resume_state(state);
1715                 } else {
1716                         int skip;
1717
1718                         if (state->rebasing)
1719                                 skip = parse_mail_rebase(state, mail);
1720                         else
1721                                 skip = parse_mail(state, mail);
1722
1723                         if (skip)
1724                                 goto next; /* mail should be skipped */
1725
1726                         if (state->signoff)
1727                                 am_append_signoff(state);
1728
1729                         write_author_script(state);
1730                         write_commit_msg(state);
1731                 }
1732
1733                 if (state->interactive && do_interactive(state))
1734                         goto next;
1735
1736                 if (run_applypatch_msg_hook(state))
1737                         exit(1);
1738
1739                 say(state, stdout, _("Applying: %.*s"), linelen(state->msg), state->msg);
1740
1741                 apply_status = run_apply(state, NULL);
1742
1743                 if (apply_status && state->threeway) {
1744                         struct strbuf sb = STRBUF_INIT;
1745
1746                         strbuf_addstr(&sb, am_path(state, "patch-merge-index"));
1747                         apply_status = fall_back_threeway(state, sb.buf);
1748                         strbuf_release(&sb);
1749
1750                         /*
1751                          * Applying the patch to an earlier tree and merging
1752                          * the result may have produced the same tree as ours.
1753                          */
1754                         if (!apply_status &&
1755                             !repo_index_has_changes(the_repository, NULL, NULL)) {
1756                                 say(state, stdout, _("No changes -- Patch already applied."));
1757                                 goto next;
1758                         }
1759                 }
1760
1761                 if (apply_status) {
1762                         printf_ln(_("Patch failed at %s %.*s"), msgnum(state),
1763                                 linelen(state->msg), state->msg);
1764
1765                         if (advice_amworkdir)
1766                                 advise(_("Use 'git am --show-current-patch' to see the failed patch"));
1767
1768                         die_user_resolve(state);
1769                 }
1770
1771                 do_commit(state);
1772
1773 next:
1774                 am_next(state);
1775
1776                 if (resume)
1777                         am_load(state);
1778                 resume = 0;
1779         }
1780
1781         if (!is_empty_or_missing_file(am_path(state, "rewritten"))) {
1782                 assert(state->rebasing);
1783                 copy_notes_for_rebase(state);
1784                 run_post_rewrite_hook(state);
1785         }
1786
1787         /*
1788          * In rebasing mode, it's up to the caller to take care of
1789          * housekeeping.
1790          */
1791         if (!state->rebasing) {
1792                 am_destroy(state);
1793                 close_object_store(the_repository->objects);
1794                 run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
1795         }
1796 }
1797
1798 /**
1799  * Resume the current am session after patch application failure. The user did
1800  * all the hard work, and we do not have to do any patch application. Just
1801  * trust and commit what the user has in the index and working tree.
1802  */
1803 static void am_resolve(struct am_state *state)
1804 {
1805         validate_resume_state(state);
1806
1807         say(state, stdout, _("Applying: %.*s"), linelen(state->msg), state->msg);
1808
1809         if (!repo_index_has_changes(the_repository, NULL, NULL)) {
1810                 printf_ln(_("No changes - did you forget to use 'git add'?\n"
1811                         "If there is nothing left to stage, chances are that something else\n"
1812                         "already introduced the same changes; you might want to skip this patch."));
1813                 die_user_resolve(state);
1814         }
1815
1816         if (unmerged_cache()) {
1817                 printf_ln(_("You still have unmerged paths in your index.\n"
1818                         "You should 'git add' each file with resolved conflicts to mark them as such.\n"
1819                         "You might run `git rm` on a file to accept \"deleted by them\" for it."));
1820                 die_user_resolve(state);
1821         }
1822
1823         if (state->interactive) {
1824                 write_index_patch(state);
1825                 if (do_interactive(state))
1826                         goto next;
1827         }
1828
1829         repo_rerere(the_repository, 0);
1830
1831         do_commit(state);
1832
1833 next:
1834         am_next(state);
1835         am_load(state);
1836         am_run(state, 0);
1837 }
1838
1839 /**
1840  * Performs a checkout fast-forward from `head` to `remote`. If `reset` is
1841  * true, any unmerged entries will be discarded. Returns 0 on success, -1 on
1842  * failure.
1843  */
1844 static int fast_forward_to(struct tree *head, struct tree *remote, int reset)
1845 {
1846         struct lock_file lock_file = LOCK_INIT;
1847         struct unpack_trees_options opts;
1848         struct tree_desc t[2];
1849
1850         if (parse_tree(head) || parse_tree(remote))
1851                 return -1;
1852
1853         hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
1854
1855         refresh_cache(REFRESH_QUIET);
1856
1857         memset(&opts, 0, sizeof(opts));
1858         opts.head_idx = 1;
1859         opts.src_index = &the_index;
1860         opts.dst_index = &the_index;
1861         opts.update = 1;
1862         opts.merge = 1;
1863         opts.reset = reset;
1864         opts.fn = twoway_merge;
1865         init_tree_desc(&t[0], head->buffer, head->size);
1866         init_tree_desc(&t[1], remote->buffer, remote->size);
1867
1868         if (unpack_trees(2, t, &opts)) {
1869                 rollback_lock_file(&lock_file);
1870                 return -1;
1871         }
1872
1873         if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
1874                 die(_("unable to write new index file"));
1875
1876         return 0;
1877 }
1878
1879 /**
1880  * Merges a tree into the index. The index's stat info will take precedence
1881  * over the merged tree's. Returns 0 on success, -1 on failure.
1882  */
1883 static int merge_tree(struct tree *tree)
1884 {
1885         struct lock_file lock_file = LOCK_INIT;
1886         struct unpack_trees_options opts;
1887         struct tree_desc t[1];
1888
1889         if (parse_tree(tree))
1890                 return -1;
1891
1892         hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
1893
1894         memset(&opts, 0, sizeof(opts));
1895         opts.head_idx = 1;
1896         opts.src_index = &the_index;
1897         opts.dst_index = &the_index;
1898         opts.merge = 1;
1899         opts.fn = oneway_merge;
1900         init_tree_desc(&t[0], tree->buffer, tree->size);
1901
1902         if (unpack_trees(1, t, &opts)) {
1903                 rollback_lock_file(&lock_file);
1904                 return -1;
1905         }
1906
1907         if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
1908                 die(_("unable to write new index file"));
1909
1910         return 0;
1911 }
1912
1913 /**
1914  * Clean the index without touching entries that are not modified between
1915  * `head` and `remote`.
1916  */
1917 static int clean_index(const struct object_id *head, const struct object_id *remote)
1918 {
1919         struct tree *head_tree, *remote_tree, *index_tree;
1920         struct object_id index;
1921
1922         head_tree = parse_tree_indirect(head);
1923         if (!head_tree)
1924                 return error(_("Could not parse object '%s'."), oid_to_hex(head));
1925
1926         remote_tree = parse_tree_indirect(remote);
1927         if (!remote_tree)
1928                 return error(_("Could not parse object '%s'."), oid_to_hex(remote));
1929
1930         read_cache_unmerged();
1931
1932         if (fast_forward_to(head_tree, head_tree, 1))
1933                 return -1;
1934
1935         if (write_cache_as_tree(&index, 0, NULL))
1936                 return -1;
1937
1938         index_tree = parse_tree_indirect(&index);
1939         if (!index_tree)
1940                 return error(_("Could not parse object '%s'."), oid_to_hex(&index));
1941
1942         if (fast_forward_to(index_tree, remote_tree, 0))
1943                 return -1;
1944
1945         if (merge_tree(remote_tree))
1946                 return -1;
1947
1948         remove_branch_state(the_repository, 0);
1949
1950         return 0;
1951 }
1952
1953 /**
1954  * Resets rerere's merge resolution metadata.
1955  */
1956 static void am_rerere_clear(void)
1957 {
1958         struct string_list merge_rr = STRING_LIST_INIT_DUP;
1959         rerere_clear(the_repository, &merge_rr);
1960         string_list_clear(&merge_rr, 1);
1961 }
1962
1963 /**
1964  * Resume the current am session by skipping the current patch.
1965  */
1966 static void am_skip(struct am_state *state)
1967 {
1968         struct object_id head;
1969
1970         am_rerere_clear();
1971
1972         if (get_oid("HEAD", &head))
1973                 oidcpy(&head, the_hash_algo->empty_tree);
1974
1975         if (clean_index(&head, &head))
1976                 die(_("failed to clean index"));
1977
1978         if (state->rebasing) {
1979                 FILE *fp = xfopen(am_path(state, "rewritten"), "a");
1980
1981                 assert(!is_null_oid(&state->orig_commit));
1982                 fprintf(fp, "%s ", oid_to_hex(&state->orig_commit));
1983                 fprintf(fp, "%s\n", oid_to_hex(&head));
1984                 fclose(fp);
1985         }
1986
1987         am_next(state);
1988         am_load(state);
1989         am_run(state, 0);
1990 }
1991
1992 /**
1993  * Returns true if it is safe to reset HEAD to the ORIG_HEAD, false otherwise.
1994  *
1995  * It is not safe to reset HEAD when:
1996  * 1. git-am previously failed because the index was dirty.
1997  * 2. HEAD has moved since git-am previously failed.
1998  */
1999 static int safe_to_abort(const struct am_state *state)
2000 {
2001         struct strbuf sb = STRBUF_INIT;
2002         struct object_id abort_safety, head;
2003
2004         if (file_exists(am_path(state, "dirtyindex")))
2005                 return 0;
2006
2007         if (read_state_file(&sb, state, "abort-safety", 1) > 0) {
2008                 if (get_oid_hex(sb.buf, &abort_safety))
2009                         die(_("could not parse %s"), am_path(state, "abort-safety"));
2010         } else
2011                 oidclr(&abort_safety);
2012         strbuf_release(&sb);
2013
2014         if (get_oid("HEAD", &head))
2015                 oidclr(&head);
2016
2017         if (oideq(&head, &abort_safety))
2018                 return 1;
2019
2020         warning(_("You seem to have moved HEAD since the last 'am' failure.\n"
2021                 "Not rewinding to ORIG_HEAD"));
2022
2023         return 0;
2024 }
2025
2026 /**
2027  * Aborts the current am session if it is safe to do so.
2028  */
2029 static void am_abort(struct am_state *state)
2030 {
2031         struct object_id curr_head, orig_head;
2032         int has_curr_head, has_orig_head;
2033         char *curr_branch;
2034
2035         if (!safe_to_abort(state)) {
2036                 am_destroy(state);
2037                 return;
2038         }
2039
2040         am_rerere_clear();
2041
2042         curr_branch = resolve_refdup("HEAD", 0, &curr_head, NULL);
2043         has_curr_head = curr_branch && !is_null_oid(&curr_head);
2044         if (!has_curr_head)
2045                 oidcpy(&curr_head, the_hash_algo->empty_tree);
2046
2047         has_orig_head = !get_oid("ORIG_HEAD", &orig_head);
2048         if (!has_orig_head)
2049                 oidcpy(&orig_head, the_hash_algo->empty_tree);
2050
2051         clean_index(&curr_head, &orig_head);
2052
2053         if (has_orig_head)
2054                 update_ref("am --abort", "HEAD", &orig_head,
2055                            has_curr_head ? &curr_head : NULL, 0,
2056                            UPDATE_REFS_DIE_ON_ERR);
2057         else if (curr_branch)
2058                 delete_ref(NULL, curr_branch, NULL, REF_NO_DEREF);
2059
2060         free(curr_branch);
2061         am_destroy(state);
2062 }
2063
2064 static int show_patch(struct am_state *state)
2065 {
2066         struct strbuf sb = STRBUF_INIT;
2067         const char *patch_path;
2068         int len;
2069
2070         if (!is_null_oid(&state->orig_commit)) {
2071                 const char *av[4] = { "show", NULL, "--", NULL };
2072                 char *new_oid_str;
2073                 int ret;
2074
2075                 av[1] = new_oid_str = xstrdup(oid_to_hex(&state->orig_commit));
2076                 ret = run_command_v_opt(av, RUN_GIT_CMD);
2077                 free(new_oid_str);
2078                 return ret;
2079         }
2080
2081         patch_path = am_path(state, msgnum(state));
2082         len = strbuf_read_file(&sb, patch_path, 0);
2083         if (len < 0)
2084                 die_errno(_("failed to read '%s'"), patch_path);
2085
2086         setup_pager();
2087         write_in_full(1, sb.buf, sb.len);
2088         strbuf_release(&sb);
2089         return 0;
2090 }
2091
2092 /**
2093  * parse_options() callback that validates and sets opt->value to the
2094  * PATCH_FORMAT_* enum value corresponding to `arg`.
2095  */
2096 static int parse_opt_patchformat(const struct option *opt, const char *arg, int unset)
2097 {
2098         int *opt_value = opt->value;
2099
2100         if (unset)
2101                 *opt_value = PATCH_FORMAT_UNKNOWN;
2102         else if (!strcmp(arg, "mbox"))
2103                 *opt_value = PATCH_FORMAT_MBOX;
2104         else if (!strcmp(arg, "stgit"))
2105                 *opt_value = PATCH_FORMAT_STGIT;
2106         else if (!strcmp(arg, "stgit-series"))
2107                 *opt_value = PATCH_FORMAT_STGIT_SERIES;
2108         else if (!strcmp(arg, "hg"))
2109                 *opt_value = PATCH_FORMAT_HG;
2110         else if (!strcmp(arg, "mboxrd"))
2111                 *opt_value = PATCH_FORMAT_MBOXRD;
2112         /*
2113          * Please update $__git_patchformat in git-completion.bash
2114          * when you add new options
2115          */
2116         else
2117                 return error(_("Invalid value for --patch-format: %s"), arg);
2118         return 0;
2119 }
2120
2121 enum resume_mode {
2122         RESUME_FALSE = 0,
2123         RESUME_APPLY,
2124         RESUME_RESOLVED,
2125         RESUME_SKIP,
2126         RESUME_ABORT,
2127         RESUME_QUIT,
2128         RESUME_SHOW_PATCH
2129 };
2130
2131 static int git_am_config(const char *k, const char *v, void *cb)
2132 {
2133         int status;
2134
2135         status = git_gpg_config(k, v, NULL);
2136         if (status)
2137                 return status;
2138
2139         return git_default_config(k, v, NULL);
2140 }
2141
2142 int cmd_am(int argc, const char **argv, const char *prefix)
2143 {
2144         struct am_state state;
2145         int binary = -1;
2146         int keep_cr = -1;
2147         int patch_format = PATCH_FORMAT_UNKNOWN;
2148         enum resume_mode resume = RESUME_FALSE;
2149         int in_progress;
2150         int ret = 0;
2151
2152         const char * const usage[] = {
2153                 N_("git am [<options>] [(<mbox> | <Maildir>)...]"),
2154                 N_("git am [<options>] (--continue | --skip | --abort)"),
2155                 NULL
2156         };
2157
2158         struct option options[] = {
2159                 OPT_BOOL('i', "interactive", &state.interactive,
2160                         N_("run interactively")),
2161                 OPT_HIDDEN_BOOL('b', "binary", &binary,
2162                         N_("historical option -- no-op")),
2163                 OPT_BOOL('3', "3way", &state.threeway,
2164                         N_("allow fall back on 3way merging if needed")),
2165                 OPT__QUIET(&state.quiet, N_("be quiet")),
2166                 OPT_SET_INT('s', "signoff", &state.signoff,
2167                         N_("add a Signed-off-by line to the commit message"),
2168                         SIGNOFF_EXPLICIT),
2169                 OPT_BOOL('u', "utf8", &state.utf8,
2170                         N_("recode into utf8 (default)")),
2171                 OPT_SET_INT('k', "keep", &state.keep,
2172                         N_("pass -k flag to git-mailinfo"), KEEP_TRUE),
2173                 OPT_SET_INT(0, "keep-non-patch", &state.keep,
2174                         N_("pass -b flag to git-mailinfo"), KEEP_NON_PATCH),
2175                 OPT_BOOL('m', "message-id", &state.message_id,
2176                         N_("pass -m flag to git-mailinfo")),
2177                 OPT_SET_INT_F(0, "keep-cr", &keep_cr,
2178                         N_("pass --keep-cr flag to git-mailsplit for mbox format"),
2179                         1, PARSE_OPT_NONEG),
2180                 OPT_SET_INT_F(0, "no-keep-cr", &keep_cr,
2181                         N_("do not pass --keep-cr flag to git-mailsplit independent of am.keepcr"),
2182                         0, PARSE_OPT_NONEG),
2183                 OPT_BOOL('c', "scissors", &state.scissors,
2184                         N_("strip everything before a scissors line")),
2185                 OPT_PASSTHRU_ARGV(0, "whitespace", &state.git_apply_opts, N_("action"),
2186                         N_("pass it through git-apply"),
2187                         0),
2188                 OPT_PASSTHRU_ARGV(0, "ignore-space-change", &state.git_apply_opts, NULL,
2189                         N_("pass it through git-apply"),
2190                         PARSE_OPT_NOARG),
2191                 OPT_PASSTHRU_ARGV(0, "ignore-whitespace", &state.git_apply_opts, NULL,
2192                         N_("pass it through git-apply"),
2193                         PARSE_OPT_NOARG),
2194                 OPT_PASSTHRU_ARGV(0, "directory", &state.git_apply_opts, N_("root"),
2195                         N_("pass it through git-apply"),
2196                         0),
2197                 OPT_PASSTHRU_ARGV(0, "exclude", &state.git_apply_opts, N_("path"),
2198                         N_("pass it through git-apply"),
2199                         0),
2200                 OPT_PASSTHRU_ARGV(0, "include", &state.git_apply_opts, N_("path"),
2201                         N_("pass it through git-apply"),
2202                         0),
2203                 OPT_PASSTHRU_ARGV('C', NULL, &state.git_apply_opts, N_("n"),
2204                         N_("pass it through git-apply"),
2205                         0),
2206                 OPT_PASSTHRU_ARGV('p', NULL, &state.git_apply_opts, N_("num"),
2207                         N_("pass it through git-apply"),
2208                         0),
2209                 OPT_CALLBACK(0, "patch-format", &patch_format, N_("format"),
2210                         N_("format the patch(es) are in"),
2211                         parse_opt_patchformat),
2212                 OPT_PASSTHRU_ARGV(0, "reject", &state.git_apply_opts, NULL,
2213                         N_("pass it through git-apply"),
2214                         PARSE_OPT_NOARG),
2215                 OPT_STRING(0, "resolvemsg", &state.resolvemsg, NULL,
2216                         N_("override error message when patch failure occurs")),
2217                 OPT_CMDMODE(0, "continue", &resume,
2218                         N_("continue applying patches after resolving a conflict"),
2219                         RESUME_RESOLVED),
2220                 OPT_CMDMODE('r', "resolved", &resume,
2221                         N_("synonyms for --continue"),
2222                         RESUME_RESOLVED),
2223                 OPT_CMDMODE(0, "skip", &resume,
2224                         N_("skip the current patch"),
2225                         RESUME_SKIP),
2226                 OPT_CMDMODE(0, "abort", &resume,
2227                         N_("restore the original branch and abort the patching operation."),
2228                         RESUME_ABORT),
2229                 OPT_CMDMODE(0, "quit", &resume,
2230                         N_("abort the patching operation but keep HEAD where it is."),
2231                         RESUME_QUIT),
2232                 OPT_CMDMODE(0, "show-current-patch", &resume,
2233                         N_("show the patch being applied."),
2234                         RESUME_SHOW_PATCH),
2235                 OPT_BOOL(0, "committer-date-is-author-date",
2236                         &state.committer_date_is_author_date,
2237                         N_("lie about committer date")),
2238                 OPT_BOOL(0, "ignore-date", &state.ignore_date,
2239                         N_("use current timestamp for author date")),
2240                 OPT_RERERE_AUTOUPDATE(&state.allow_rerere_autoupdate),
2241                 { OPTION_STRING, 'S', "gpg-sign", &state.sign_commit, N_("key-id"),
2242                   N_("GPG-sign commits"),
2243                   PARSE_OPT_OPTARG, NULL, (intptr_t) "" },
2244                 OPT_HIDDEN_BOOL(0, "rebasing", &state.rebasing,
2245                         N_("(internal use for git-rebase)")),
2246                 OPT_END()
2247         };
2248
2249         if (argc == 2 && !strcmp(argv[1], "-h"))
2250                 usage_with_options(usage, options);
2251
2252         git_config(git_am_config, NULL);
2253
2254         am_state_init(&state);
2255
2256         in_progress = am_in_progress(&state);
2257         if (in_progress)
2258                 am_load(&state);
2259
2260         argc = parse_options(argc, argv, prefix, options, usage, 0);
2261
2262         if (binary >= 0)
2263                 fprintf_ln(stderr, _("The -b/--binary option has been a no-op for long time, and\n"
2264                                 "it will be removed. Please do not use it anymore."));
2265
2266         /* Ensure a valid committer ident can be constructed */
2267         git_committer_info(IDENT_STRICT);
2268
2269         if (repo_read_index_preload(the_repository, NULL, 0) < 0)
2270                 die(_("failed to read the index"));
2271
2272         if (in_progress) {
2273                 /*
2274                  * Catch user error to feed us patches when there is a session
2275                  * in progress:
2276                  *
2277                  * 1. mbox path(s) are provided on the command-line.
2278                  * 2. stdin is not a tty: the user is trying to feed us a patch
2279                  *    from standard input. This is somewhat unreliable -- stdin
2280                  *    could be /dev/null for example and the caller did not
2281                  *    intend to feed us a patch but wanted to continue
2282                  *    unattended.
2283                  */
2284                 if (argc || (resume == RESUME_FALSE && !isatty(0)))
2285                         die(_("previous rebase directory %s still exists but mbox given."),
2286                                 state.dir);
2287
2288                 if (resume == RESUME_FALSE)
2289                         resume = RESUME_APPLY;
2290
2291                 if (state.signoff == SIGNOFF_EXPLICIT)
2292                         am_append_signoff(&state);
2293         } else {
2294                 struct argv_array paths = ARGV_ARRAY_INIT;
2295                 int i;
2296
2297                 /*
2298                  * Handle stray state directory in the independent-run case. In
2299                  * the --rebasing case, it is up to the caller to take care of
2300                  * stray directories.
2301                  */
2302                 if (file_exists(state.dir) && !state.rebasing) {
2303                         if (resume == RESUME_ABORT || resume == RESUME_QUIT) {
2304                                 am_destroy(&state);
2305                                 am_state_release(&state);
2306                                 return 0;
2307                         }
2308
2309                         die(_("Stray %s directory found.\n"
2310                                 "Use \"git am --abort\" to remove it."),
2311                                 state.dir);
2312                 }
2313
2314                 if (resume)
2315                         die(_("Resolve operation not in progress, we are not resuming."));
2316
2317                 for (i = 0; i < argc; i++) {
2318                         if (is_absolute_path(argv[i]) || !prefix)
2319                                 argv_array_push(&paths, argv[i]);
2320                         else
2321                                 argv_array_push(&paths, mkpath("%s/%s", prefix, argv[i]));
2322                 }
2323
2324                 if (state.interactive && !paths.argc)
2325                         die(_("interactive mode requires patches on the command line"));
2326
2327                 am_setup(&state, patch_format, paths.argv, keep_cr);
2328
2329                 argv_array_clear(&paths);
2330         }
2331
2332         switch (resume) {
2333         case RESUME_FALSE:
2334                 am_run(&state, 0);
2335                 break;
2336         case RESUME_APPLY:
2337                 am_run(&state, 1);
2338                 break;
2339         case RESUME_RESOLVED:
2340                 am_resolve(&state);
2341                 break;
2342         case RESUME_SKIP:
2343                 am_skip(&state);
2344                 break;
2345         case RESUME_ABORT:
2346                 am_abort(&state);
2347                 break;
2348         case RESUME_QUIT:
2349                 am_rerere_clear();
2350                 am_destroy(&state);
2351                 break;
2352         case RESUME_SHOW_PATCH:
2353                 ret = show_patch(&state);
2354                 break;
2355         default:
2356                 BUG("invalid resume value");
2357         }
2358
2359         am_state_release(&state);
2360
2361         return ret;
2362 }