aboutsummaryrefslogtreecommitdiff
path: root/builtin-for-each-ref.c
blob: 21e92bbcb577c0361df51bd81e6fb5ab546619ea (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
#include "builtin.h"
#include "cache.h"
#include "refs.h"
#include "object.h"
#include "tag.h"
#include "commit.h"
#include "tree.h"
#include "blob.h"
#include "quote.h"
#include "parse-options.h"

/* Quoting styles */
#define QUOTE_NONE 0
#define QUOTE_SHELL 1
#define QUOTE_PERL 2
#define QUOTE_PYTHON 4
#define QUOTE_TCL 8

typedef enum { FIELD_STR, FIELD_ULONG, FIELD_TIME } cmp_type;

struct atom_value {
	const char *s;
	unsigned long ul; /* used for sorting when not FIELD_STR */
};

struct ref_sort {
	struct ref_sort *next;
	int atom; /* index into used_atom array */
	unsigned reverse : 1;
};

struct refinfo {
	char *refname;
	unsigned char objectname[20];
	struct atom_value *value;
};

static struct {
	const char *name;
	cmp_type cmp_type;
} valid_atom[] = {
	{ "refname" },
	{ "objecttype" },
	{ "objectsize", FIELD_ULONG },
	{ "objectname" },
	{ "tree" },
	{ "parent" },
	{ "numparent", FIELD_ULONG },
	{ "object" },
	{ "type" },
	{ "tag" },
	{ "author" },
	{ "authorname" },
	{ "authoremail" },
	{ "authordate", FIELD_TIME },
	{ "committer" },
	{ "committername" },
	{ "committeremail" },
	{ "committerdate", FIELD_TIME },
	{ "tagger" },
	{ "taggername" },
	{ "taggeremail" },
	{ "taggerdate", FIELD_TIME },
	{ "creator" },
	{ "creatordate", FIELD_TIME },
	{ "subject" },
	{ "body" },
	{ "contents" },
};

/*
 * An atom is a valid field atom listed above, possibly prefixed with
 * a "*" to denote deref_tag().
 *
 * We parse given format string and sort specifiers, and make a list
 * of properties that we need to extract out of objects.  refinfo
 * structure will hold an array of values extracted that can be
 * indexed with the "atom number", which is an index into this
 * array.
 */
static const char **used_atom;
static cmp_type *used_atom_type;
static int used_atom_cnt, sort_atom_limit, need_tagged;

/*
 * Used to parse format string and sort specifiers
 */
static int parse_atom(const char *atom, const char *ep)
{
	const char *sp;
	int i, at;

	sp = atom;
	if (*sp == '*' && sp < ep)
		sp++; /* deref */
	if (ep <= sp)
		die("malformed field name: %.*s", (int)(ep-atom), atom);

	/* Do we have the atom already used elsewhere? */
	for (i = 0; i < used_atom_cnt; i++) {
		int len = strlen(used_atom[i]);
		if (len == ep - atom && !memcmp(used_atom[i], atom, len))
			return i;
	}

	/* Is the atom a valid one? */
	for (i = 0; i < ARRAY_SIZE(valid_atom); i++) {
		int len = strlen(valid_atom[i].name);
		/*
		 * If the atom name has a colon, strip it and everything after
		 * it off - it specifies the format for this entry, and
		 * shouldn't be used for checking against the valid_atom
		 * table.
		 */
		const char *formatp = strchr(sp, ':');
		if (!formatp || ep < formatp)
			formatp = ep;
		if (len == formatp - sp && !memcmp(valid_atom[i].name, sp, len))
			break;
	}

	if (ARRAY_SIZE(valid_atom) <= i)
		die("unknown field name: %.*s", (int)(ep-atom), atom);

	/* Add it in, including the deref prefix */
	at = used_atom_cnt;
	used_atom_cnt++;
	used_atom = xrealloc(used_atom,
			     (sizeof *used_atom) * used_atom_cnt);
	used_atom_type = xrealloc(used_atom_type,
				  (sizeof(*used_atom_type) * used_atom_cnt));
	used_atom[at] = xmemdupz(atom, ep - atom);
	used_atom_type[at] = valid_atom[i].cmp_type;
	return at;
}

/*
 * In a format string, find the next occurrence of %(atom).
 */
static const char *find_next(const char *cp)
{
	while (*cp) {
		if (*cp == '%') {
			/* %( is the start of an atom;
			 * %% is a quoted per-cent.
			 */
			if (cp[1] == '(')
				return cp;
			else if (cp[1] == '%')
				cp++; /* skip over two % */
			/* otherwise this is a singleton, literal % */
		}
		cp++;
	}
	return NULL;
}

/*
 * Make sure the format string is well formed, and parse out
 * the used atoms.
 */
static int verify_format(const char *format)
{
	const char *cp, *sp;
	for (cp = format; *cp && (sp = find_next(cp)); ) {
		const char *ep = strchr(sp, ')');
		if (!ep)
			return error("malformed format string %s", sp);
		/* sp points at "%(" and ep points at the closing ")" */
		parse_atom(sp + 2, ep);
		cp = ep + 1;
	}
	return 0;
}

/*
 * Given an object name, read the object data and size, and return a
 * "struct object".  If the object data we are returning is also borrowed
 * by the "struct object" representation, set *eaten as well---it is a
 * signal from parse_object_buffer to us not to free the buffer.
 */
static void *get_obj(const unsigned char *sha1, struct object **obj, unsigned long *sz, int *eaten)
{
	enum object_type type;
	void *buf = read_sha1_file(sha1, &type, sz);

	if (buf)
		*obj = parse_object_buffer(sha1, type, *sz, buf, eaten);
	else
		*obj = NULL;
	return buf;
}

/* See grab_values */
static void grab_common_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
{
	int i;

	for (i = 0; i < used_atom_cnt; i++) {
		const char *name = used_atom[i];
		struct atom_value *v = &val[i];
		if (!!deref != (*name == '*'))
			continue;
		if (deref)
			name++;
		if (!strcmp(name, "objecttype"))
			v->s = typename(obj->type);
		else if (!strcmp(name, "objectsize")) {
			char *s = xmalloc(40);
			sprintf(s, "%lu", sz);
			v->ul = sz;
			v->s = s;
		}
		else if (!strcmp(name, "objectname")) {
			char *s = xmalloc(41);
			strcpy(s, sha1_to_hex(obj->sha1));
			v->s = s;
		}
	}
}

/* See grab_values */
static void grab_tag_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
{
	int i;
	struct tag *tag = (struct tag *) obj;

	for (i = 0; i < used_atom_cnt; i++) {
		const char *name = used_atom[i];
		struct atom_value *v = &val[i];
		if (!!deref != (*name == '*'))
			continue;
		if (deref)
			name++;
		if (!strcmp(name, "tag"))
			v->s = tag->tag;
		else if (!strcmp(name, "type") && tag->tagged)
			v->s = typename(tag->tagged->type);
		else if (!strcmp(name, "object") && tag->tagged) {
			char *s = xmalloc(41);
			strcpy(s, sha1_to_hex(tag->tagged->sha1));
			v->s = s;
		}
	}
}

static int num_parents(struct commit *commit)
{
	struct commit_list *parents;
	int i;

	for (i = 0, parents = commit->parents;
	     parents;
	     parents = parents->next)
		i++;
	return i;
}

/* See grab_values */
static void grab_commit_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
{
	int i;
	struct commit *commit = (struct commit *) obj;

	for (i = 0; i < used_atom_cnt; i++) {
		const char *name = used_atom[i];
		struct atom_value *v = &val[i];
		if (!!deref != (*name == '*'))
			continue;
		if (deref)
			name++;
		if (!strcmp(name, "tree")) {
			char *s = xmalloc(41);
			strcpy(s, sha1_to_hex(commit->tree->object.sha1));
			v->s = s;
		}
		if (!strcmp(name, "numparent")) {
			char *s = xmalloc(40);
			v->ul = num_parents(commit);
			sprintf(s, "%lu", v->ul);
			v->s = s;
		}
		else if (!strcmp(name, "parent")) {
			int num = num_parents(commit);
			int i;
			struct commit_list *parents;
			char *s = xmalloc(41 * num + 1);
			v->s = s;
			for (i = 0, parents = commit->parents;
			     parents;
			     parents = parents->next, i = i + 41) {
				struct commit *parent = parents->item;
				strcpy(s+i, sha1_to_hex(parent->object.sha1));
				if (parents->next)
					s[i+40] = ' ';
			}
			if (!i)
				*s = '\0';
		}
	}
}

static const char *find_wholine(const char *who, int wholen, const char *buf, unsigned long sz)
{
	const char *eol;
	while (*buf) {
		if (!strncmp(buf, who, wholen) &&
		    buf[wholen] == ' ')
			return buf + wholen + 1;
		eol = strchr(buf, '\n');
		if (!eol)
			return "";
		eol++;
		if (*eol == '\n')
			return ""; /* end of header */
		buf = eol;
	}
	return "";
}

static const char *copy_line(const char *buf)
{
	const char *eol = strchr(buf, '\n');
	if (!eol)
		return "";
	return xmemdupz(buf, eol - buf);
}

static const char *copy_name(const char *buf)
{
	const char *cp;
	for (cp = buf; *cp && *cp != '\n'; cp++) {
		if (!strncmp(cp, " <", 2))
			return xmemdupz(buf, cp - buf);
	}
	return "";
}

static const char *copy_email(const char *buf)
{
	const char *email = strchr(buf, '<');
	const char *eoemail = strchr(email, '>');
	if (!email || !eoemail)
		return "";
	return xmemdupz(email, eoemail + 1 - email);
}

static void grab_date(const char *buf, struct atom_value *v, const char *atomname)
{
	const char *eoemail = strstr(buf, "> ");
	char *zone;
	unsigned long timestamp;
	long tz;
	enum date_mode date_mode = DATE_NORMAL;
	const char *formatp;

	/*
	 * We got here because atomname ends in "date" or "date<something>";
	 * it's not possible that <something> is not ":<format>" because
	 * parse_atom() wouldn't have allowed it, so we can assume that no
	 * ":" means no format is specified, and use the default.
	 */
	formatp = strchr(atomname, ':');
	if (formatp != NULL) {
		formatp++;
		date_mode = parse_date_format(formatp);
	}

	if (!eoemail)
		goto bad;
	timestamp = strtoul(eoemail + 2, &zone, 10);
	if (timestamp == ULONG_MAX)
		goto bad;
	tz = strtol(zone, NULL, 10);
	if ((tz == LONG_MIN || tz == LONG_MAX) && errno == ERANGE)
		goto bad;
	v->s = xstrdup(show_date(timestamp, tz, date_mode));
	v->ul = timestamp;
	return;
 bad:
	v->s = "";
	v->ul = 0;
}

/* See grab_values */
static void grab_person(const char *who, struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
{
	int i;
	int wholen = strlen(who);
	const char *wholine = NULL;

	for (i = 0; i < used_atom_cnt; i++) {
		const char *name = used_atom[i];
		struct atom_value *v = &val[i];
		if (!!deref != (*name == '*'))
			continue;
		if (deref)
			name++;
		if (strncmp(who, name, wholen))
			continue;
		if (name[wholen] != 0 &&
		    strcmp(name + wholen, "name") &&
		    strcmp(name + wholen, "email") &&
		    prefixcmp(name + wholen, "date"))
			continue;
		if (!wholine)
			wholine = find_wholine(who, wholen, buf, sz);
		if (!wholine)
			return; /* no point looking for it */
		if (name[wholen] == 0)
			v->s = copy_line(wholine);
		else if (!strcmp(name + wholen, "name"))
			v->s = copy_name(wholine);
		else if (!strcmp(name + wholen, "email"))
			v->s = copy_email(wholine);
		else if (!prefixcmp(name + wholen, "date"))
			grab_date(wholine, v, name);
	}

	/* For a tag or a commit object, if "creator" or "creatordate" is
	 * requested, do something special.
	 */
	if (strcmp(who, "tagger") && strcmp(who, "committer"))
		return; /* "author" for commit object is not wanted */
	if (!wholine)
		wholine = find_wholine(who, wholen, buf, sz);
	if (!wholine)
		return;
	for (i = 0; i < used_atom_cnt; i++) {
		const char *name = used_atom[i];
		struct atom_value *v = &val[i];
		if (!!deref != (*name == '*'))
			continue;
		if (deref)
			name++;

		if (!prefixcmp(name, "creatordate"))
			grab_date(wholine, v, name);
		else if (!strcmp(name, "creator"))
			v->s = copy_line(wholine);
	}
}

static void find_subpos(const char *buf, unsigned long sz, const char **sub, const char **body)
{
	while (*buf) {
		const char *eol = strchr(buf, '\n');
		if (!eol)
			return;
		if (eol[1] == '\n') {
			buf = eol + 1;
			break; /* found end of header */
		}
		buf = eol + 1;
	}
	while (*buf == '\n')
		buf++;
	if (!*buf)
		return;
	*sub = buf; /* first non-empty line */
	buf = strchr(buf, '\n');
	if (!buf) {
		*body = "";
		return; /* no body */
	}
	while (*buf == '\n')
		buf++; /* skip blank between subject and body */
	*body = buf;
}

/* See grab_values */
static void grab_sub_body_contents(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
{
	int i;
	const char *subpos = NULL, *bodypos = NULL;

	for (i = 0; i < used_atom_cnt; i++) {
		const char *name = used_atom[i];
		struct atom_value *v = &val[i];
		if (!!deref != (*name == '*'))
			continue;
		if (deref)
			name++;
		if (strcmp(name, "subject") &&
		    strcmp(name, "body") &&
		    strcmp(name, "contents"))
			continue;
		if (!subpos)
			find_subpos(buf, sz, &subpos, &bodypos);
		if (!subpos)
			return;

		if (!strcmp(name, "subject"))
			v->s = copy_line(subpos);
		else if (!strcmp(name, "body"))
			v->s = xstrdup(bodypos);
		else if (!strcmp(name, "contents"))
			v->s = xstrdup(subpos);
	}
}

/* We want to have empty print-string for field requests
 * that do not apply (e.g. "authordate" for a tag object)
 */
static void fill_missing_values(struct atom_value *val)
{
	int i;
	for (i = 0; i < used_atom_cnt; i++) {
		struct atom_value *v = &val[i];
		if (v->s == NULL)
			v->s = "";
	}
}

/*
 * val is a list of atom_value to hold returned values.  Extract
 * the values for atoms in used_atom array out of (obj, buf, sz).
 * when deref is false, (obj, buf, sz) is the object that is
 * pointed at by the ref itself; otherwise it is the object the
 * ref (which is a tag) refers to.
 */
static void grab_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
{
	grab_common_values(val, deref, obj, buf, sz);
	switch (obj->type) {
	case OBJ_TAG:
		grab_tag_values(val, deref, obj, buf, sz);
		grab_sub_body_contents(val, deref, obj, buf, sz);
		grab_person("tagger", val, deref, obj, buf, sz);
		break;
	case OBJ_COMMIT:
		grab_commit_values(val, deref, obj, buf, sz);
		grab_sub_body_contents(val, deref, obj, buf, sz);
		grab_person("author", val, deref, obj, buf, sz);
		grab_person("committer", val, deref, obj, buf, sz);
		break;
	case OBJ_TREE:
		// grab_tree_values(val, deref, obj, buf, sz);
		break;
	case OBJ_BLOB:
		// grab_blob_values(val, deref, obj, buf, sz);
		break;
	default:
		die("Eh?  Object of type %d?", obj->type);
	}
}

/*
 * Parse the object referred by ref, and grab needed value.
 */
static void populate_value(struct refinfo *ref)
{
	void *buf;
	struct object *obj;
	int eaten, i;
	unsigned long size;
	const unsigned char *tagged;

	ref->value = xcalloc(sizeof(struct atom_value), used_atom_cnt);

	buf = get_obj(ref->objectname, &obj, &size, &eaten);
	if (!buf)
		die("missing object %s for %s",
		    sha1_to_hex(ref->objectname), ref->refname);
	if (!obj)
		die("parse_object_buffer failed on %s for %s",
		    sha1_to_hex(ref->objectname), ref->refname);

	/* Fill in specials first */
	for (i = 0; i < used_atom_cnt; i++) {
		const char *name = used_atom[i];
		struct atom_value *v = &ref->value[i];
		if (!strcmp(name, "refname"))
			v->s = ref->refname;
		else if (!strcmp(name, "*refname")) {
			int len = strlen(ref->refname);
			char *s = xmalloc(len + 4);
			sprintf(s, "%s^{}", ref->refname);
			v->s = s;
		}
	}

	grab_values(ref->value, 0, obj, buf, size);
	if (!eaten)
		free(buf);

	/* If there is no atom that wants to know about tagged
	 * object, we are done.
	 */
	if (!need_tagged || (obj->type != OBJ_TAG))
		return;

	/* If it is a tag object, see if we use a value that derefs
	 * the object, and if we do grab the object it refers to.
	 */
	tagged = ((struct tag *)obj)->tagged->sha1;

	/* NEEDSWORK: This derefs tag only once, which
	 * is good to deal with chains of trust, but
	 * is not consistent with what deref_tag() does
	 * which peels the onion to the core.
	 */
	buf = get_obj(tagged, &obj, &size, &eaten);
	if (!buf)
		die("missing object %s for %s",
		    sha1_to_hex(tagged), ref->refname);
	if (!obj)
		die("parse_object_buffer failed on %s for %s",
		    sha1_to_hex(tagged), ref->refname);
	grab_values(ref->value, 1, obj, buf, size);
	if (!eaten)
		free(buf);
}

/*
 * Given a ref, return the value for the atom.  This lazily gets value
 * out of the object by calling populate value.
 */
static void get_value(struct refinfo *ref, int atom, struct atom_value **v)
{
	if (!ref->value) {
		populate_value(ref);
		fill_missing_values(ref->value);
	}
	*v = &ref->value[atom];
}

struct grab_ref_cbdata {
	struct refinfo **grab_array;
	const char **grab_pattern;
	int grab_cnt;
};

/*
 * A call-back given to for_each_ref().  It is unfortunate that we
 * need to use global variables to pass extra information to this
 * function.
 */
static int grab_single_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
{
	struct grab_ref_cbdata *cb = cb_data;
	struct refinfo *ref;
	int cnt;

	if (*cb->grab_pattern) {
		const char **pattern;
		int namelen = strlen(refname);
		for (pattern = cb->grab_pattern; *pattern; pattern++) {
			const char *p = *pattern;
			int plen = strlen(p);

			if ((plen <= namelen) &&
			    !strncmp(refname, p, plen) &&
			    (refname[plen] == '\0' ||
			     refname[plen] == '/' ||
			     p[plen-1] == '/'))
				break;
			if (!fnmatch(p, refname, FNM_PATHNAME))
				break;
		}
		if (!*pattern)
			return 0;
	}

	/* We do not open the object yet; sort may only need refname
	 * to do its job and the resulting list may yet to be pruned
	 * by maxcount logic.
	 */
	ref = xcalloc(1, sizeof(*ref));
	ref->refname = xstrdup(refname);
	hashcpy(ref->objectname, sha1);

	cnt = cb->grab_cnt;
	cb->grab_array = xrealloc(cb->grab_array,
				  sizeof(*cb->grab_array) * (cnt + 1));
	cb->grab_array[cnt++] = ref;
	cb->grab_cnt = cnt;
	return 0;
}

static int cmp_ref_sort(struct ref_sort *s, struct refinfo *a, struct refinfo *b)
{
	struct atom_value *va, *vb;
	int cmp;
	cmp_type cmp_type = used_atom_type[s->atom];

	get_value(a, s->atom, &va);
	get_value(b, s->atom, &vb);
	switch (cmp_type) {
	case FIELD_STR:
		cmp = strcmp(va->s, vb->s);
		break;
	default:
		if (va->ul < vb->ul)
			cmp = -1;
		else if (va->ul == vb->ul)
			cmp = 0;
		else
			cmp = 1;
		break;
	}
	return (s->reverse) ? -cmp : cmp;
}

static struct ref_sort *ref_sort;
static int compare_refs(const void *a_, const void *b_)
{
	struct refinfo *a = *((struct refinfo **)a_);
	struct refinfo *b = *((struct refinfo **)b_);
	struct ref_sort *s;

	for (s = ref_sort; s; s = s->next) {
		int cmp = cmp_ref_sort(s, a, b);
		if (cmp)
			return cmp;
	}
	return 0;
}

static void sort_refs(struct ref_sort *sort, struct refinfo **refs, int num_refs)
{
	ref_sort = sort;
	qsort(refs, num_refs, sizeof(struct refinfo *), compare_refs);
}

static void print_value(struct refinfo *ref, int atom, int quote_style)
{
	struct atom_value *v;
	get_value(ref, atom, &v);
	switch (quote_style) {
	case QUOTE_NONE:
		fputs(v->s, stdout);
		break;
	case QUOTE_SHELL:
		sq_quote_print(stdout, v->s);
		break;
	case QUOTE_PERL:
		perl_quote_print(stdout, v->s);
		break;
	case QUOTE_PYTHON:
		python_quote_print(stdout, v->s);
		break;
	case QUOTE_TCL:
		tcl_quote_print(stdout, v->s);
		break;
	}
}

static int hex1(char ch)
{
	if ('0' <= ch && ch <= '9')
		return ch - '0';
	else if ('a' <= ch && ch <= 'f')
		return ch - 'a' + 10;
	else if ('A' <= ch && ch <= 'F')
		return ch - 'A' + 10;
	return -1;
}
static int hex2(const char *cp)
{
	if (cp[0] && cp[1])
		return (hex1(cp[0]) << 4) | hex1(cp[1]);
	else
		return -1;
}

static void emit(const char *cp, const char *ep)
{
	while (*cp && (!ep || cp < ep)) {
		if (*cp == '%') {
			if (cp[1] == '%')
				cp++;
			else {
				int ch = hex2(cp + 1);
				if (0 <= ch) {
					putchar(ch);
					cp += 3;
					continue;
				}
			}
		}
		putchar(*cp);
		cp++;
	}
}

static void show_ref(struct refinfo *info, const char *format, int quote_style)
{
	const char *cp, *sp, *ep;

	for (cp = format; *cp && (sp = find_next(cp)); cp = ep + 1) {
		ep = strchr(sp, ')');
		if (cp < sp)
			emit(cp, sp);
		print_value(info, parse_atom(sp + 2, ep), quote_style);
	}
	if (*cp) {
		sp = cp + strlen(cp);
		emit(cp, sp);
	}
	putchar('\n');
}

static struct ref_sort *default_sort(void)
{
	static const char cstr_name[] = "refname";

	struct ref_sort *sort = xcalloc(1, sizeof(*sort));

	sort->next = NULL;
	sort->atom = parse_atom(cstr_name, cstr_name + strlen(cstr_name));
	return sort;
}

static int opt_parse_sort(const struct option *opt, const char *arg, int unset)
{
	struct ref_sort **sort_tail = opt->value;
	struct ref_sort *s;
	int len;

	if (!arg) /* should --no-sort void the list ? */
		return -1;

	*sort_tail = s = xcalloc(1, sizeof(*s));
	sort_tail = &s->next;

	if (*arg == '-') {
		s->reverse = 1;
		arg++;
	}
	len = strlen(arg);
	s->atom = parse_atom(arg, arg+len);
	return 0;
}

static char const * const for_each_ref_usage[] = {
	"git for-each-ref [options] [<pattern>]",
	NULL
};

int cmd_for_each_ref(int argc, const char **argv, const char *prefix)
{
	int i, num_refs;
	const char *format = "%(objectname) %(objecttype)\t%(refname)";
	struct ref_sort *sort = NULL, **sort_tail = &sort;
	int maxcount = 0, quote_style = 0;
	struct refinfo **refs;
	struct grab_ref_cbdata cbdata;

	struct option opts[] = {
		OPT_BIT('s', "shell", &quote_style,
		        "quote placeholders suitably for shells", QUOTE_SHELL),
		OPT_BIT('p', "perl",  &quote_style,
		        "quote placeholders suitably for perl", QUOTE_PERL),
		OPT_BIT(0 , "python", &quote_style,
		        "quote placeholders suitably for python", QUOTE_PYTHON),
		OPT_BIT(0 , "tcl",  &quote_style,
		        "quote placeholders suitably for tcl", QUOTE_TCL),

		OPT_GROUP(""),
		OPT_INTEGER( 0 , "count", &maxcount, "show only <n> matched refs"),
		OPT_STRING(  0 , "format", &format, "format", "format to use for the output"),
		OPT_CALLBACK(0 , "sort", sort_tail, "key",
		            "field name to sort on", &opt_parse_sort),
		OPT_END(),
	};

	parse_options(argc, argv, opts, for_each_ref_usage, 0);
	if (maxcount < 0) {
		error("invalid --count argument: `%d'", maxcount);
		usage_with_options(for_each_ref_usage, opts);
	}
	if (HAS_MULTI_BITS(quote_style)) {
		error("more than one quoting style?");
		usage_with_options(for_each_ref_usage, opts);
	}
	if (verify_format(format))
		usage_with_options(for_each_ref_usage, opts);

	if (!sort)
		sort = default_sort();
	sort_atom_limit = used_atom_cnt;

	memset(&cbdata, 0, sizeof(cbdata));
	cbdata.grab_pattern = argv;
	for_each_ref(grab_single_ref, &cbdata);
	refs = cbdata.grab_array;
	num_refs = cbdata.grab_cnt;

	for (i = 0; i < used_atom_cnt; i++) {
		if (used_atom[i][0] == '*') {
			need_tagged = 1;
			break;
		}
	}

	sort_refs(sort, refs, num_refs);

	if (!maxcount || num_refs < maxcount)
		maxcount = num_refs;
	for (i = 0; i < maxcount; i++)
		show_ref(refs[i], format, quote_style);
	return 0;
}