Merge branch 'ss/submodule-set-url-in-c'
[git] / ref-filter.c
1 #include "builtin.h"
2 #include "cache.h"
3 #include "parse-options.h"
4 #include "refs.h"
5 #include "wildmatch.h"
6 #include "object-store.h"
7 #include "repository.h"
8 #include "commit.h"
9 #include "remote.h"
10 #include "color.h"
11 #include "tag.h"
12 #include "quote.h"
13 #include "ref-filter.h"
14 #include "revision.h"
15 #include "utf8.h"
16 #include "git-compat-util.h"
17 #include "version.h"
18 #include "trailer.h"
19 #include "wt-status.h"
20 #include "commit-slab.h"
21 #include "commit-graph.h"
22 #include "commit-reach.h"
23 #include "worktree.h"
24 #include "hashmap.h"
25 #include "argv-array.h"
26
27 static struct ref_msg {
28         const char *gone;
29         const char *ahead;
30         const char *behind;
31         const char *ahead_behind;
32 } msgs = {
33          /* Untranslated plumbing messages: */
34         "gone",
35         "ahead %d",
36         "behind %d",
37         "ahead %d, behind %d"
38 };
39
40 void setup_ref_filter_porcelain_msg(void)
41 {
42         msgs.gone = _("gone");
43         msgs.ahead = _("ahead %d");
44         msgs.behind = _("behind %d");
45         msgs.ahead_behind = _("ahead %d, behind %d");
46 }
47
48 typedef enum { FIELD_STR, FIELD_ULONG, FIELD_TIME } cmp_type;
49 typedef enum { COMPARE_EQUAL, COMPARE_UNEQUAL, COMPARE_NONE } cmp_status;
50 typedef enum { SOURCE_NONE = 0, SOURCE_OBJ, SOURCE_OTHER } info_source;
51
52 struct align {
53         align_type position;
54         unsigned int width;
55 };
56
57 struct if_then_else {
58         cmp_status cmp_status;
59         const char *str;
60         unsigned int then_atom_seen : 1,
61                 else_atom_seen : 1,
62                 condition_satisfied : 1;
63 };
64
65 struct refname_atom {
66         enum { R_NORMAL, R_SHORT, R_LSTRIP, R_RSTRIP } option;
67         int lstrip, rstrip;
68 };
69
70 static struct expand_data {
71         struct object_id oid;
72         enum object_type type;
73         unsigned long size;
74         off_t disk_size;
75         struct object_id delta_base_oid;
76         void *content;
77
78         struct object_info info;
79 } oi, oi_deref;
80
81 struct ref_to_worktree_entry {
82         struct hashmap_entry ent;
83         struct worktree *wt; /* key is wt->head_ref */
84 };
85
86 static int ref_to_worktree_map_cmpfnc(const void *unused_lookupdata,
87                                       const struct hashmap_entry *eptr,
88                                       const struct hashmap_entry *kptr,
89                                       const void *keydata_aka_refname)
90 {
91         const struct ref_to_worktree_entry *e, *k;
92
93         e = container_of(eptr, const struct ref_to_worktree_entry, ent);
94         k = container_of(kptr, const struct ref_to_worktree_entry, ent);
95
96         return strcmp(e->wt->head_ref,
97                 keydata_aka_refname ? keydata_aka_refname : k->wt->head_ref);
98 }
99
100 static struct ref_to_worktree_map {
101         struct hashmap map;
102         struct worktree **worktrees;
103 } ref_to_worktree_map;
104
105 /*
106  * An atom is a valid field atom listed below, possibly prefixed with
107  * a "*" to denote deref_tag().
108  *
109  * We parse given format string and sort specifiers, and make a list
110  * of properties that we need to extract out of objects.  ref_array_item
111  * structure will hold an array of values extracted that can be
112  * indexed with the "atom number", which is an index into this
113  * array.
114  */
115 static struct used_atom {
116         const char *name;
117         cmp_type type;
118         info_source source;
119         union {
120                 char color[COLOR_MAXLEN];
121                 struct align align;
122                 struct {
123                         enum {
124                                 RR_REF, RR_TRACK, RR_TRACKSHORT, RR_REMOTE_NAME, RR_REMOTE_REF
125                         } option;
126                         struct refname_atom refname;
127                         unsigned int nobracket : 1, push : 1, push_remote : 1;
128                 } remote_ref;
129                 struct {
130                         enum { C_BARE, C_BODY, C_BODY_DEP, C_LINES, C_SIG, C_SUB, C_TRAILERS } option;
131                         struct process_trailer_options trailer_opts;
132                         unsigned int nlines;
133                 } contents;
134                 struct {
135                         cmp_status cmp_status;
136                         const char *str;
137                 } if_then_else;
138                 struct {
139                         enum { O_FULL, O_LENGTH, O_SHORT } option;
140                         unsigned int length;
141                 } objectname;
142                 struct refname_atom refname;
143                 char *head;
144         } u;
145 } *used_atom;
146 static int used_atom_cnt, need_tagged, need_symref;
147
148 /*
149  * Expand string, append it to strbuf *sb, then return error code ret.
150  * Allow to save few lines of code.
151  */
152 static int strbuf_addf_ret(struct strbuf *sb, int ret, const char *fmt, ...)
153 {
154         va_list ap;
155         va_start(ap, fmt);
156         strbuf_vaddf(sb, fmt, ap);
157         va_end(ap);
158         return ret;
159 }
160
161 static int color_atom_parser(const struct ref_format *format, struct used_atom *atom,
162                              const char *color_value, struct strbuf *err)
163 {
164         if (!color_value)
165                 return strbuf_addf_ret(err, -1, _("expected format: %%(color:<color>)"));
166         if (color_parse(color_value, atom->u.color) < 0)
167                 return strbuf_addf_ret(err, -1, _("unrecognized color: %%(color:%s)"),
168                                        color_value);
169         /*
170          * We check this after we've parsed the color, which lets us complain
171          * about syntactically bogus color names even if they won't be used.
172          */
173         if (!want_color(format->use_color))
174                 color_parse("", atom->u.color);
175         return 0;
176 }
177
178 static int refname_atom_parser_internal(struct refname_atom *atom, const char *arg,
179                                          const char *name, struct strbuf *err)
180 {
181         if (!arg)
182                 atom->option = R_NORMAL;
183         else if (!strcmp(arg, "short"))
184                 atom->option = R_SHORT;
185         else if (skip_prefix(arg, "lstrip=", &arg) ||
186                  skip_prefix(arg, "strip=", &arg)) {
187                 atom->option = R_LSTRIP;
188                 if (strtol_i(arg, 10, &atom->lstrip))
189                         return strbuf_addf_ret(err, -1, _("Integer value expected refname:lstrip=%s"), arg);
190         } else if (skip_prefix(arg, "rstrip=", &arg)) {
191                 atom->option = R_RSTRIP;
192                 if (strtol_i(arg, 10, &atom->rstrip))
193                         return strbuf_addf_ret(err, -1, _("Integer value expected refname:rstrip=%s"), arg);
194         } else
195                 return strbuf_addf_ret(err, -1, _("unrecognized %%(%s) argument: %s"), name, arg);
196         return 0;
197 }
198
199 static int remote_ref_atom_parser(const struct ref_format *format, struct used_atom *atom,
200                                   const char *arg, struct strbuf *err)
201 {
202         struct string_list params = STRING_LIST_INIT_DUP;
203         int i;
204
205         if (!strcmp(atom->name, "push") || starts_with(atom->name, "push:"))
206                 atom->u.remote_ref.push = 1;
207
208         if (!arg) {
209                 atom->u.remote_ref.option = RR_REF;
210                 return refname_atom_parser_internal(&atom->u.remote_ref.refname,
211                                                     arg, atom->name, err);
212         }
213
214         atom->u.remote_ref.nobracket = 0;
215         string_list_split(&params, arg, ',', -1);
216
217         for (i = 0; i < params.nr; i++) {
218                 const char *s = params.items[i].string;
219
220                 if (!strcmp(s, "track"))
221                         atom->u.remote_ref.option = RR_TRACK;
222                 else if (!strcmp(s, "trackshort"))
223                         atom->u.remote_ref.option = RR_TRACKSHORT;
224                 else if (!strcmp(s, "nobracket"))
225                         atom->u.remote_ref.nobracket = 1;
226                 else if (!strcmp(s, "remotename")) {
227                         atom->u.remote_ref.option = RR_REMOTE_NAME;
228                         atom->u.remote_ref.push_remote = 1;
229                 } else if (!strcmp(s, "remoteref")) {
230                         atom->u.remote_ref.option = RR_REMOTE_REF;
231                         atom->u.remote_ref.push_remote = 1;
232                 } else {
233                         atom->u.remote_ref.option = RR_REF;
234                         if (refname_atom_parser_internal(&atom->u.remote_ref.refname,
235                                                          arg, atom->name, err)) {
236                                 string_list_clear(&params, 0);
237                                 return -1;
238                         }
239                 }
240         }
241
242         string_list_clear(&params, 0);
243         return 0;
244 }
245
246 static int objecttype_atom_parser(const struct ref_format *format, struct used_atom *atom,
247                                   const char *arg, struct strbuf *err)
248 {
249         if (arg)
250                 return strbuf_addf_ret(err, -1, _("%%(objecttype) does not take arguments"));
251         if (*atom->name == '*')
252                 oi_deref.info.typep = &oi_deref.type;
253         else
254                 oi.info.typep = &oi.type;
255         return 0;
256 }
257
258 static int objectsize_atom_parser(const struct ref_format *format, struct used_atom *atom,
259                                   const char *arg, struct strbuf *err)
260 {
261         if (!arg) {
262                 if (*atom->name == '*')
263                         oi_deref.info.sizep = &oi_deref.size;
264                 else
265                         oi.info.sizep = &oi.size;
266         } else if (!strcmp(arg, "disk")) {
267                 if (*atom->name == '*')
268                         oi_deref.info.disk_sizep = &oi_deref.disk_size;
269                 else
270                         oi.info.disk_sizep = &oi.disk_size;
271         } else
272                 return strbuf_addf_ret(err, -1, _("unrecognized %%(objectsize) argument: %s"), arg);
273         return 0;
274 }
275
276 static int deltabase_atom_parser(const struct ref_format *format, struct used_atom *atom,
277                                  const char *arg, struct strbuf *err)
278 {
279         if (arg)
280                 return strbuf_addf_ret(err, -1, _("%%(deltabase) does not take arguments"));
281         if (*atom->name == '*')
282                 oi_deref.info.delta_base_oid = &oi_deref.delta_base_oid;
283         else
284                 oi.info.delta_base_oid = &oi.delta_base_oid;
285         return 0;
286 }
287
288 static int body_atom_parser(const struct ref_format *format, struct used_atom *atom,
289                             const char *arg, struct strbuf *err)
290 {
291         if (arg)
292                 return strbuf_addf_ret(err, -1, _("%%(body) does not take arguments"));
293         atom->u.contents.option = C_BODY_DEP;
294         return 0;
295 }
296
297 static int subject_atom_parser(const struct ref_format *format, struct used_atom *atom,
298                                const char *arg, struct strbuf *err)
299 {
300         if (arg)
301                 return strbuf_addf_ret(err, -1, _("%%(subject) does not take arguments"));
302         atom->u.contents.option = C_SUB;
303         return 0;
304 }
305
306 static int trailers_atom_parser(const struct ref_format *format, struct used_atom *atom,
307                                 const char *arg, struct strbuf *err)
308 {
309         struct string_list params = STRING_LIST_INIT_DUP;
310         int i;
311
312         atom->u.contents.trailer_opts.no_divider = 1;
313
314         if (arg) {
315                 string_list_split(&params, arg, ',', -1);
316                 for (i = 0; i < params.nr; i++) {
317                         const char *s = params.items[i].string;
318                         if (!strcmp(s, "unfold"))
319                                 atom->u.contents.trailer_opts.unfold = 1;
320                         else if (!strcmp(s, "only"))
321                                 atom->u.contents.trailer_opts.only_trailers = 1;
322                         else {
323                                 strbuf_addf(err, _("unknown %%(trailers) argument: %s"), s);
324                                 string_list_clear(&params, 0);
325                                 return -1;
326                         }
327                 }
328         }
329         atom->u.contents.option = C_TRAILERS;
330         string_list_clear(&params, 0);
331         return 0;
332 }
333
334 static int contents_atom_parser(const struct ref_format *format, struct used_atom *atom,
335                                 const char *arg, struct strbuf *err)
336 {
337         if (!arg)
338                 atom->u.contents.option = C_BARE;
339         else if (!strcmp(arg, "body"))
340                 atom->u.contents.option = C_BODY;
341         else if (!strcmp(arg, "signature"))
342                 atom->u.contents.option = C_SIG;
343         else if (!strcmp(arg, "subject"))
344                 atom->u.contents.option = C_SUB;
345         else if (skip_prefix(arg, "trailers", &arg)) {
346                 skip_prefix(arg, ":", &arg);
347                 if (trailers_atom_parser(format, atom, *arg ? arg : NULL, err))
348                         return -1;
349         } else if (skip_prefix(arg, "lines=", &arg)) {
350                 atom->u.contents.option = C_LINES;
351                 if (strtoul_ui(arg, 10, &atom->u.contents.nlines))
352                         return strbuf_addf_ret(err, -1, _("positive value expected contents:lines=%s"), arg);
353         } else
354                 return strbuf_addf_ret(err, -1, _("unrecognized %%(contents) argument: %s"), arg);
355         return 0;
356 }
357
358 static int objectname_atom_parser(const struct ref_format *format, struct used_atom *atom,
359                                   const char *arg, struct strbuf *err)
360 {
361         if (!arg)
362                 atom->u.objectname.option = O_FULL;
363         else if (!strcmp(arg, "short"))
364                 atom->u.objectname.option = O_SHORT;
365         else if (skip_prefix(arg, "short=", &arg)) {
366                 atom->u.objectname.option = O_LENGTH;
367                 if (strtoul_ui(arg, 10, &atom->u.objectname.length) ||
368                     atom->u.objectname.length == 0)
369                         return strbuf_addf_ret(err, -1, _("positive value expected objectname:short=%s"), arg);
370                 if (atom->u.objectname.length < MINIMUM_ABBREV)
371                         atom->u.objectname.length = MINIMUM_ABBREV;
372         } else
373                 return strbuf_addf_ret(err, -1, _("unrecognized %%(objectname) argument: %s"), arg);
374         return 0;
375 }
376
377 static int refname_atom_parser(const struct ref_format *format, struct used_atom *atom,
378                                const char *arg, struct strbuf *err)
379 {
380         return refname_atom_parser_internal(&atom->u.refname, arg, atom->name, err);
381 }
382
383 static align_type parse_align_position(const char *s)
384 {
385         if (!strcmp(s, "right"))
386                 return ALIGN_RIGHT;
387         else if (!strcmp(s, "middle"))
388                 return ALIGN_MIDDLE;
389         else if (!strcmp(s, "left"))
390                 return ALIGN_LEFT;
391         return -1;
392 }
393
394 static int align_atom_parser(const struct ref_format *format, struct used_atom *atom,
395                              const char *arg, struct strbuf *err)
396 {
397         struct align *align = &atom->u.align;
398         struct string_list params = STRING_LIST_INIT_DUP;
399         int i;
400         unsigned int width = ~0U;
401
402         if (!arg)
403                 return strbuf_addf_ret(err, -1, _("expected format: %%(align:<width>,<position>)"));
404
405         align->position = ALIGN_LEFT;
406
407         string_list_split(&params, arg, ',', -1);
408         for (i = 0; i < params.nr; i++) {
409                 const char *s = params.items[i].string;
410                 int position;
411
412                 if (skip_prefix(s, "position=", &s)) {
413                         position = parse_align_position(s);
414                         if (position < 0) {
415                                 strbuf_addf(err, _("unrecognized position:%s"), s);
416                                 string_list_clear(&params, 0);
417                                 return -1;
418                         }
419                         align->position = position;
420                 } else if (skip_prefix(s, "width=", &s)) {
421                         if (strtoul_ui(s, 10, &width)) {
422                                 strbuf_addf(err, _("unrecognized width:%s"), s);
423                                 string_list_clear(&params, 0);
424                                 return -1;
425                         }
426                 } else if (!strtoul_ui(s, 10, &width))
427                         ;
428                 else if ((position = parse_align_position(s)) >= 0)
429                         align->position = position;
430                 else {
431                         strbuf_addf(err, _("unrecognized %%(align) argument: %s"), s);
432                         string_list_clear(&params, 0);
433                         return -1;
434                 }
435         }
436
437         if (width == ~0U) {
438                 string_list_clear(&params, 0);
439                 return strbuf_addf_ret(err, -1, _("positive width expected with the %%(align) atom"));
440         }
441         align->width = width;
442         string_list_clear(&params, 0);
443         return 0;
444 }
445
446 static int if_atom_parser(const struct ref_format *format, struct used_atom *atom,
447                           const char *arg, struct strbuf *err)
448 {
449         if (!arg) {
450                 atom->u.if_then_else.cmp_status = COMPARE_NONE;
451                 return 0;
452         } else if (skip_prefix(arg, "equals=", &atom->u.if_then_else.str)) {
453                 atom->u.if_then_else.cmp_status = COMPARE_EQUAL;
454         } else if (skip_prefix(arg, "notequals=", &atom->u.if_then_else.str)) {
455                 atom->u.if_then_else.cmp_status = COMPARE_UNEQUAL;
456         } else
457                 return strbuf_addf_ret(err, -1, _("unrecognized %%(if) argument: %s"), arg);
458         return 0;
459 }
460
461 static int head_atom_parser(const struct ref_format *format, struct used_atom *atom,
462                             const char *arg, struct strbuf *unused_err)
463 {
464         atom->u.head = resolve_refdup("HEAD", RESOLVE_REF_READING, NULL, NULL);
465         return 0;
466 }
467
468 static struct {
469         const char *name;
470         info_source source;
471         cmp_type cmp_type;
472         int (*parser)(const struct ref_format *format, struct used_atom *atom,
473                       const char *arg, struct strbuf *err);
474 } valid_atom[] = {
475         { "refname", SOURCE_NONE, FIELD_STR, refname_atom_parser },
476         { "objecttype", SOURCE_OTHER, FIELD_STR, objecttype_atom_parser },
477         { "objectsize", SOURCE_OTHER, FIELD_ULONG, objectsize_atom_parser },
478         { "objectname", SOURCE_OTHER, FIELD_STR, objectname_atom_parser },
479         { "deltabase", SOURCE_OTHER, FIELD_STR, deltabase_atom_parser },
480         { "tree", SOURCE_OBJ },
481         { "parent", SOURCE_OBJ },
482         { "numparent", SOURCE_OBJ, FIELD_ULONG },
483         { "object", SOURCE_OBJ },
484         { "type", SOURCE_OBJ },
485         { "tag", SOURCE_OBJ },
486         { "author", SOURCE_OBJ },
487         { "authorname", SOURCE_OBJ },
488         { "authoremail", SOURCE_OBJ },
489         { "authordate", SOURCE_OBJ, FIELD_TIME },
490         { "committer", SOURCE_OBJ },
491         { "committername", SOURCE_OBJ },
492         { "committeremail", SOURCE_OBJ },
493         { "committerdate", SOURCE_OBJ, FIELD_TIME },
494         { "tagger", SOURCE_OBJ },
495         { "taggername", SOURCE_OBJ },
496         { "taggeremail", SOURCE_OBJ },
497         { "taggerdate", SOURCE_OBJ, FIELD_TIME },
498         { "creator", SOURCE_OBJ },
499         { "creatordate", SOURCE_OBJ, FIELD_TIME },
500         { "subject", SOURCE_OBJ, FIELD_STR, subject_atom_parser },
501         { "body", SOURCE_OBJ, FIELD_STR, body_atom_parser },
502         { "trailers", SOURCE_OBJ, FIELD_STR, trailers_atom_parser },
503         { "contents", SOURCE_OBJ, FIELD_STR, contents_atom_parser },
504         { "upstream", SOURCE_NONE, FIELD_STR, remote_ref_atom_parser },
505         { "push", SOURCE_NONE, FIELD_STR, remote_ref_atom_parser },
506         { "symref", SOURCE_NONE, FIELD_STR, refname_atom_parser },
507         { "flag", SOURCE_NONE },
508         { "HEAD", SOURCE_NONE, FIELD_STR, head_atom_parser },
509         { "color", SOURCE_NONE, FIELD_STR, color_atom_parser },
510         { "worktreepath", SOURCE_NONE },
511         { "align", SOURCE_NONE, FIELD_STR, align_atom_parser },
512         { "end", SOURCE_NONE },
513         { "if", SOURCE_NONE, FIELD_STR, if_atom_parser },
514         { "then", SOURCE_NONE },
515         { "else", SOURCE_NONE },
516         /*
517          * Please update $__git_ref_fieldlist in git-completion.bash
518          * when you add new atoms
519          */
520 };
521
522 #define REF_FORMATTING_STATE_INIT  { 0, NULL }
523
524 struct ref_formatting_stack {
525         struct ref_formatting_stack *prev;
526         struct strbuf output;
527         void (*at_end)(struct ref_formatting_stack **stack);
528         void *at_end_data;
529 };
530
531 struct ref_formatting_state {
532         int quote_style;
533         struct ref_formatting_stack *stack;
534 };
535
536 struct atom_value {
537         const char *s;
538         int (*handler)(struct atom_value *atomv, struct ref_formatting_state *state,
539                        struct strbuf *err);
540         uintmax_t value; /* used for sorting when not FIELD_STR */
541         struct used_atom *atom;
542 };
543
544 /*
545  * Used to parse format string and sort specifiers
546  */
547 static int parse_ref_filter_atom(const struct ref_format *format,
548                                  const char *atom, const char *ep,
549                                  struct strbuf *err)
550 {
551         const char *sp;
552         const char *arg;
553         int i, at, atom_len;
554
555         sp = atom;
556         if (*sp == '*' && sp < ep)
557                 sp++; /* deref */
558         if (ep <= sp)
559                 return strbuf_addf_ret(err, -1, _("malformed field name: %.*s"),
560                                        (int)(ep-atom), atom);
561
562         /* Do we have the atom already used elsewhere? */
563         for (i = 0; i < used_atom_cnt; i++) {
564                 int len = strlen(used_atom[i].name);
565                 if (len == ep - atom && !memcmp(used_atom[i].name, atom, len))
566                         return i;
567         }
568
569         /*
570          * If the atom name has a colon, strip it and everything after
571          * it off - it specifies the format for this entry, and
572          * shouldn't be used for checking against the valid_atom
573          * table.
574          */
575         arg = memchr(sp, ':', ep - sp);
576         atom_len = (arg ? arg : ep) - sp;
577
578         /* Is the atom a valid one? */
579         for (i = 0; i < ARRAY_SIZE(valid_atom); i++) {
580                 int len = strlen(valid_atom[i].name);
581                 if (len == atom_len && !memcmp(valid_atom[i].name, sp, len))
582                         break;
583         }
584
585         if (ARRAY_SIZE(valid_atom) <= i)
586                 return strbuf_addf_ret(err, -1, _("unknown field name: %.*s"),
587                                        (int)(ep-atom), atom);
588         if (valid_atom[i].source != SOURCE_NONE && !have_git_dir())
589                 return strbuf_addf_ret(err, -1,
590                                        _("not a git repository, but the field '%.*s' requires access to object data"),
591                                        (int)(ep-atom), atom);
592
593         /* Add it in, including the deref prefix */
594         at = used_atom_cnt;
595         used_atom_cnt++;
596         REALLOC_ARRAY(used_atom, used_atom_cnt);
597         used_atom[at].name = xmemdupz(atom, ep - atom);
598         used_atom[at].type = valid_atom[i].cmp_type;
599         used_atom[at].source = valid_atom[i].source;
600         if (used_atom[at].source == SOURCE_OBJ) {
601                 if (*atom == '*')
602                         oi_deref.info.contentp = &oi_deref.content;
603                 else
604                         oi.info.contentp = &oi.content;
605         }
606         if (arg) {
607                 arg = used_atom[at].name + (arg - atom) + 1;
608                 if (!*arg) {
609                         /*
610                          * Treat empty sub-arguments list as NULL (i.e.,
611                          * "%(atom:)" is equivalent to "%(atom)").
612                          */
613                         arg = NULL;
614                 }
615         }
616         memset(&used_atom[at].u, 0, sizeof(used_atom[at].u));
617         if (valid_atom[i].parser && valid_atom[i].parser(format, &used_atom[at], arg, err))
618                 return -1;
619         if (*atom == '*')
620                 need_tagged = 1;
621         if (!strcmp(valid_atom[i].name, "symref"))
622                 need_symref = 1;
623         return at;
624 }
625
626 static void quote_formatting(struct strbuf *s, const char *str, int quote_style)
627 {
628         switch (quote_style) {
629         case QUOTE_NONE:
630                 strbuf_addstr(s, str);
631                 break;
632         case QUOTE_SHELL:
633                 sq_quote_buf(s, str);
634                 break;
635         case QUOTE_PERL:
636                 perl_quote_buf(s, str);
637                 break;
638         case QUOTE_PYTHON:
639                 python_quote_buf(s, str);
640                 break;
641         case QUOTE_TCL:
642                 tcl_quote_buf(s, str);
643                 break;
644         }
645 }
646
647 static int append_atom(struct atom_value *v, struct ref_formatting_state *state,
648                        struct strbuf *unused_err)
649 {
650         /*
651          * Quote formatting is only done when the stack has a single
652          * element. Otherwise quote formatting is done on the
653          * element's entire output strbuf when the %(end) atom is
654          * encountered.
655          */
656         if (!state->stack->prev)
657                 quote_formatting(&state->stack->output, v->s, state->quote_style);
658         else
659                 strbuf_addstr(&state->stack->output, v->s);
660         return 0;
661 }
662
663 static void push_stack_element(struct ref_formatting_stack **stack)
664 {
665         struct ref_formatting_stack *s = xcalloc(1, sizeof(struct ref_formatting_stack));
666
667         strbuf_init(&s->output, 0);
668         s->prev = *stack;
669         *stack = s;
670 }
671
672 static void pop_stack_element(struct ref_formatting_stack **stack)
673 {
674         struct ref_formatting_stack *current = *stack;
675         struct ref_formatting_stack *prev = current->prev;
676
677         if (prev)
678                 strbuf_addbuf(&prev->output, &current->output);
679         strbuf_release(&current->output);
680         free(current);
681         *stack = prev;
682 }
683
684 static void end_align_handler(struct ref_formatting_stack **stack)
685 {
686         struct ref_formatting_stack *cur = *stack;
687         struct align *align = (struct align *)cur->at_end_data;
688         struct strbuf s = STRBUF_INIT;
689
690         strbuf_utf8_align(&s, align->position, align->width, cur->output.buf);
691         strbuf_swap(&cur->output, &s);
692         strbuf_release(&s);
693 }
694
695 static int align_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state,
696                               struct strbuf *unused_err)
697 {
698         struct ref_formatting_stack *new_stack;
699
700         push_stack_element(&state->stack);
701         new_stack = state->stack;
702         new_stack->at_end = end_align_handler;
703         new_stack->at_end_data = &atomv->atom->u.align;
704         return 0;
705 }
706
707 static void if_then_else_handler(struct ref_formatting_stack **stack)
708 {
709         struct ref_formatting_stack *cur = *stack;
710         struct ref_formatting_stack *prev = cur->prev;
711         struct if_then_else *if_then_else = (struct if_then_else *)cur->at_end_data;
712
713         if (!if_then_else->then_atom_seen)
714                 die(_("format: %%(if) atom used without a %%(then) atom"));
715
716         if (if_then_else->else_atom_seen) {
717                 /*
718                  * There is an %(else) atom: we need to drop one state from the
719                  * stack, either the %(else) branch if the condition is satisfied, or
720                  * the %(then) branch if it isn't.
721                  */
722                 if (if_then_else->condition_satisfied) {
723                         strbuf_reset(&cur->output);
724                         pop_stack_element(&cur);
725                 } else {
726                         strbuf_swap(&cur->output, &prev->output);
727                         strbuf_reset(&cur->output);
728                         pop_stack_element(&cur);
729                 }
730         } else if (!if_then_else->condition_satisfied) {
731                 /*
732                  * No %(else) atom: just drop the %(then) branch if the
733                  * condition is not satisfied.
734                  */
735                 strbuf_reset(&cur->output);
736         }
737
738         *stack = cur;
739         free(if_then_else);
740 }
741
742 static int if_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state,
743                            struct strbuf *unused_err)
744 {
745         struct ref_formatting_stack *new_stack;
746         struct if_then_else *if_then_else = xcalloc(sizeof(struct if_then_else), 1);
747
748         if_then_else->str = atomv->atom->u.if_then_else.str;
749         if_then_else->cmp_status = atomv->atom->u.if_then_else.cmp_status;
750
751         push_stack_element(&state->stack);
752         new_stack = state->stack;
753         new_stack->at_end = if_then_else_handler;
754         new_stack->at_end_data = if_then_else;
755         return 0;
756 }
757
758 static int is_empty(const char *s)
759 {
760         while (*s != '\0') {
761                 if (!isspace(*s))
762                         return 0;
763                 s++;
764         }
765         return 1;
766 }
767
768 static int then_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state,
769                              struct strbuf *err)
770 {
771         struct ref_formatting_stack *cur = state->stack;
772         struct if_then_else *if_then_else = NULL;
773
774         if (cur->at_end == if_then_else_handler)
775                 if_then_else = (struct if_then_else *)cur->at_end_data;
776         if (!if_then_else)
777                 return strbuf_addf_ret(err, -1, _("format: %%(then) atom used without an %%(if) atom"));
778         if (if_then_else->then_atom_seen)
779                 return strbuf_addf_ret(err, -1, _("format: %%(then) atom used more than once"));
780         if (if_then_else->else_atom_seen)
781                 return strbuf_addf_ret(err, -1, _("format: %%(then) atom used after %%(else)"));
782         if_then_else->then_atom_seen = 1;
783         /*
784          * If the 'equals' or 'notequals' attribute is used then
785          * perform the required comparison. If not, only non-empty
786          * strings satisfy the 'if' condition.
787          */
788         if (if_then_else->cmp_status == COMPARE_EQUAL) {
789                 if (!strcmp(if_then_else->str, cur->output.buf))
790                         if_then_else->condition_satisfied = 1;
791         } else if (if_then_else->cmp_status == COMPARE_UNEQUAL) {
792                 if (strcmp(if_then_else->str, cur->output.buf))
793                         if_then_else->condition_satisfied = 1;
794         } else if (cur->output.len && !is_empty(cur->output.buf))
795                 if_then_else->condition_satisfied = 1;
796         strbuf_reset(&cur->output);
797         return 0;
798 }
799
800 static int else_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state,
801                              struct strbuf *err)
802 {
803         struct ref_formatting_stack *prev = state->stack;
804         struct if_then_else *if_then_else = NULL;
805
806         if (prev->at_end == if_then_else_handler)
807                 if_then_else = (struct if_then_else *)prev->at_end_data;
808         if (!if_then_else)
809                 return strbuf_addf_ret(err, -1, _("format: %%(else) atom used without an %%(if) atom"));
810         if (!if_then_else->then_atom_seen)
811                 return strbuf_addf_ret(err, -1, _("format: %%(else) atom used without a %%(then) atom"));
812         if (if_then_else->else_atom_seen)
813                 return strbuf_addf_ret(err, -1, _("format: %%(else) atom used more than once"));
814         if_then_else->else_atom_seen = 1;
815         push_stack_element(&state->stack);
816         state->stack->at_end_data = prev->at_end_data;
817         state->stack->at_end = prev->at_end;
818         return 0;
819 }
820
821 static int end_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state,
822                             struct strbuf *err)
823 {
824         struct ref_formatting_stack *current = state->stack;
825         struct strbuf s = STRBUF_INIT;
826
827         if (!current->at_end)
828                 return strbuf_addf_ret(err, -1, _("format: %%(end) atom used without corresponding atom"));
829         current->at_end(&state->stack);
830
831         /*  Stack may have been popped within at_end(), hence reset the current pointer */
832         current = state->stack;
833
834         /*
835          * Perform quote formatting when the stack element is that of
836          * a supporting atom. If nested then perform quote formatting
837          * only on the topmost supporting atom.
838          */
839         if (!current->prev->prev) {
840                 quote_formatting(&s, current->output.buf, state->quote_style);
841                 strbuf_swap(&current->output, &s);
842         }
843         strbuf_release(&s);
844         pop_stack_element(&state->stack);
845         return 0;
846 }
847
848 /*
849  * In a format string, find the next occurrence of %(atom).
850  */
851 static const char *find_next(const char *cp)
852 {
853         while (*cp) {
854                 if (*cp == '%') {
855                         /*
856                          * %( is the start of an atom;
857                          * %% is a quoted per-cent.
858                          */
859                         if (cp[1] == '(')
860                                 return cp;
861                         else if (cp[1] == '%')
862                                 cp++; /* skip over two % */
863                         /* otherwise this is a singleton, literal % */
864                 }
865                 cp++;
866         }
867         return NULL;
868 }
869
870 /*
871  * Make sure the format string is well formed, and parse out
872  * the used atoms.
873  */
874 int verify_ref_format(struct ref_format *format)
875 {
876         const char *cp, *sp;
877
878         format->need_color_reset_at_eol = 0;
879         for (cp = format->format; *cp && (sp = find_next(cp)); ) {
880                 struct strbuf err = STRBUF_INIT;
881                 const char *color, *ep = strchr(sp, ')');
882                 int at;
883
884                 if (!ep)
885                         return error(_("malformed format string %s"), sp);
886                 /* sp points at "%(" and ep points at the closing ")" */
887                 at = parse_ref_filter_atom(format, sp + 2, ep, &err);
888                 if (at < 0)
889                         die("%s", err.buf);
890                 cp = ep + 1;
891
892                 if (skip_prefix(used_atom[at].name, "color:", &color))
893                         format->need_color_reset_at_eol = !!strcmp(color, "reset");
894                 strbuf_release(&err);
895         }
896         if (format->need_color_reset_at_eol && !want_color(format->use_color))
897                 format->need_color_reset_at_eol = 0;
898         return 0;
899 }
900
901 static int grab_objectname(const char *name, const struct object_id *oid,
902                            struct atom_value *v, struct used_atom *atom)
903 {
904         if (starts_with(name, "objectname")) {
905                 if (atom->u.objectname.option == O_SHORT) {
906                         v->s = xstrdup(find_unique_abbrev(oid, DEFAULT_ABBREV));
907                         return 1;
908                 } else if (atom->u.objectname.option == O_FULL) {
909                         v->s = xstrdup(oid_to_hex(oid));
910                         return 1;
911                 } else if (atom->u.objectname.option == O_LENGTH) {
912                         v->s = xstrdup(find_unique_abbrev(oid, atom->u.objectname.length));
913                         return 1;
914                 } else
915                         BUG("unknown %%(objectname) option");
916         }
917         return 0;
918 }
919
920 /* See grab_values */
921 static void grab_common_values(struct atom_value *val, int deref, struct expand_data *oi)
922 {
923         int i;
924
925         for (i = 0; i < used_atom_cnt; i++) {
926                 const char *name = used_atom[i].name;
927                 struct atom_value *v = &val[i];
928                 if (!!deref != (*name == '*'))
929                         continue;
930                 if (deref)
931                         name++;
932                 if (!strcmp(name, "objecttype"))
933                         v->s = xstrdup(type_name(oi->type));
934                 else if (!strcmp(name, "objectsize:disk")) {
935                         v->value = oi->disk_size;
936                         v->s = xstrfmt("%"PRIuMAX, (uintmax_t)oi->disk_size);
937                 } else if (!strcmp(name, "objectsize")) {
938                         v->value = oi->size;
939                         v->s = xstrfmt("%"PRIuMAX , (uintmax_t)oi->size);
940                 } else if (!strcmp(name, "deltabase"))
941                         v->s = xstrdup(oid_to_hex(&oi->delta_base_oid));
942                 else if (deref)
943                         grab_objectname(name, &oi->oid, v, &used_atom[i]);
944         }
945 }
946
947 /* See grab_values */
948 static void grab_tag_values(struct atom_value *val, int deref, struct object *obj)
949 {
950         int i;
951         struct tag *tag = (struct tag *) obj;
952
953         for (i = 0; i < used_atom_cnt; i++) {
954                 const char *name = used_atom[i].name;
955                 struct atom_value *v = &val[i];
956                 if (!!deref != (*name == '*'))
957                         continue;
958                 if (deref)
959                         name++;
960                 if (!strcmp(name, "tag"))
961                         v->s = xstrdup(tag->tag);
962                 else if (!strcmp(name, "type") && tag->tagged)
963                         v->s = xstrdup(type_name(tag->tagged->type));
964                 else if (!strcmp(name, "object") && tag->tagged)
965                         v->s = xstrdup(oid_to_hex(&tag->tagged->oid));
966         }
967 }
968
969 /* See grab_values */
970 static void grab_commit_values(struct atom_value *val, int deref, struct object *obj)
971 {
972         int i;
973         struct commit *commit = (struct commit *) obj;
974
975         for (i = 0; i < used_atom_cnt; i++) {
976                 const char *name = used_atom[i].name;
977                 struct atom_value *v = &val[i];
978                 if (!!deref != (*name == '*'))
979                         continue;
980                 if (deref)
981                         name++;
982                 if (!strcmp(name, "tree")) {
983                         v->s = xstrdup(oid_to_hex(get_commit_tree_oid(commit)));
984                 }
985                 else if (!strcmp(name, "numparent")) {
986                         v->value = commit_list_count(commit->parents);
987                         v->s = xstrfmt("%lu", (unsigned long)v->value);
988                 }
989                 else if (!strcmp(name, "parent")) {
990                         struct commit_list *parents;
991                         struct strbuf s = STRBUF_INIT;
992                         for (parents = commit->parents; parents; parents = parents->next) {
993                                 struct commit *parent = parents->item;
994                                 if (parents != commit->parents)
995                                         strbuf_addch(&s, ' ');
996                                 strbuf_addstr(&s, oid_to_hex(&parent->object.oid));
997                         }
998                         v->s = strbuf_detach(&s, NULL);
999                 }
1000         }
1001 }
1002
1003 static const char *find_wholine(const char *who, int wholen, const char *buf)
1004 {
1005         const char *eol;
1006         while (*buf) {
1007                 if (!strncmp(buf, who, wholen) &&
1008                     buf[wholen] == ' ')
1009                         return buf + wholen + 1;
1010                 eol = strchr(buf, '\n');
1011                 if (!eol)
1012                         return "";
1013                 eol++;
1014                 if (*eol == '\n')
1015                         return ""; /* end of header */
1016                 buf = eol;
1017         }
1018         return "";
1019 }
1020
1021 static const char *copy_line(const char *buf)
1022 {
1023         const char *eol = strchrnul(buf, '\n');
1024         return xmemdupz(buf, eol - buf);
1025 }
1026
1027 static const char *copy_name(const char *buf)
1028 {
1029         const char *cp;
1030         for (cp = buf; *cp && *cp != '\n'; cp++) {
1031                 if (!strncmp(cp, " <", 2))
1032                         return xmemdupz(buf, cp - buf);
1033         }
1034         return xstrdup("");
1035 }
1036
1037 static const char *copy_email(const char *buf)
1038 {
1039         const char *email = strchr(buf, '<');
1040         const char *eoemail;
1041         if (!email)
1042                 return xstrdup("");
1043         eoemail = strchr(email, '>');
1044         if (!eoemail)
1045                 return xstrdup("");
1046         return xmemdupz(email, eoemail + 1 - email);
1047 }
1048
1049 static char *copy_subject(const char *buf, unsigned long len)
1050 {
1051         char *r = xmemdupz(buf, len);
1052         int i;
1053
1054         for (i = 0; i < len; i++)
1055                 if (r[i] == '\n')
1056                         r[i] = ' ';
1057
1058         return r;
1059 }
1060
1061 static void grab_date(const char *buf, struct atom_value *v, const char *atomname)
1062 {
1063         const char *eoemail = strstr(buf, "> ");
1064         char *zone;
1065         timestamp_t timestamp;
1066         long tz;
1067         struct date_mode date_mode = { DATE_NORMAL };
1068         const char *formatp;
1069
1070         /*
1071          * We got here because atomname ends in "date" or "date<something>";
1072          * it's not possible that <something> is not ":<format>" because
1073          * parse_ref_filter_atom() wouldn't have allowed it, so we can assume that no
1074          * ":" means no format is specified, and use the default.
1075          */
1076         formatp = strchr(atomname, ':');
1077         if (formatp != NULL) {
1078                 formatp++;
1079                 parse_date_format(formatp, &date_mode);
1080         }
1081
1082         if (!eoemail)
1083                 goto bad;
1084         timestamp = parse_timestamp(eoemail + 2, &zone, 10);
1085         if (timestamp == TIME_MAX)
1086                 goto bad;
1087         tz = strtol(zone, NULL, 10);
1088         if ((tz == LONG_MIN || tz == LONG_MAX) && errno == ERANGE)
1089                 goto bad;
1090         v->s = xstrdup(show_date(timestamp, tz, &date_mode));
1091         v->value = timestamp;
1092         return;
1093  bad:
1094         v->s = xstrdup("");
1095         v->value = 0;
1096 }
1097
1098 /* See grab_values */
1099 static void grab_person(const char *who, struct atom_value *val, int deref, void *buf)
1100 {
1101         int i;
1102         int wholen = strlen(who);
1103         const char *wholine = NULL;
1104
1105         for (i = 0; i < used_atom_cnt; i++) {
1106                 const char *name = used_atom[i].name;
1107                 struct atom_value *v = &val[i];
1108                 if (!!deref != (*name == '*'))
1109                         continue;
1110                 if (deref)
1111                         name++;
1112                 if (strncmp(who, name, wholen))
1113                         continue;
1114                 if (name[wholen] != 0 &&
1115                     strcmp(name + wholen, "name") &&
1116                     strcmp(name + wholen, "email") &&
1117                     !starts_with(name + wholen, "date"))
1118                         continue;
1119                 if (!wholine)
1120                         wholine = find_wholine(who, wholen, buf);
1121                 if (!wholine)
1122                         return; /* no point looking for it */
1123                 if (name[wholen] == 0)
1124                         v->s = copy_line(wholine);
1125                 else if (!strcmp(name + wholen, "name"))
1126                         v->s = copy_name(wholine);
1127                 else if (!strcmp(name + wholen, "email"))
1128                         v->s = copy_email(wholine);
1129                 else if (starts_with(name + wholen, "date"))
1130                         grab_date(wholine, v, name);
1131         }
1132
1133         /*
1134          * For a tag or a commit object, if "creator" or "creatordate" is
1135          * requested, do something special.
1136          */
1137         if (strcmp(who, "tagger") && strcmp(who, "committer"))
1138                 return; /* "author" for commit object is not wanted */
1139         if (!wholine)
1140                 wholine = find_wholine(who, wholen, buf);
1141         if (!wholine)
1142                 return;
1143         for (i = 0; i < used_atom_cnt; i++) {
1144                 const char *name = used_atom[i].name;
1145                 struct atom_value *v = &val[i];
1146                 if (!!deref != (*name == '*'))
1147                         continue;
1148                 if (deref)
1149                         name++;
1150
1151                 if (starts_with(name, "creatordate"))
1152                         grab_date(wholine, v, name);
1153                 else if (!strcmp(name, "creator"))
1154                         v->s = copy_line(wholine);
1155         }
1156 }
1157
1158 static void find_subpos(const char *buf,
1159                         const char **sub, unsigned long *sublen,
1160                         const char **body, unsigned long *bodylen,
1161                         unsigned long *nonsiglen,
1162                         const char **sig, unsigned long *siglen)
1163 {
1164         const char *eol;
1165         /* skip past header until we hit empty line */
1166         while (*buf && *buf != '\n') {
1167                 eol = strchrnul(buf, '\n');
1168                 if (*eol)
1169                         eol++;
1170                 buf = eol;
1171         }
1172         /* skip any empty lines */
1173         while (*buf == '\n')
1174                 buf++;
1175
1176         /* parse signature first; we might not even have a subject line */
1177         *sig = buf + parse_signature(buf, strlen(buf));
1178         *siglen = strlen(*sig);
1179
1180         /* subject is first non-empty line */
1181         *sub = buf;
1182         /* subject goes to first empty line */
1183         while (buf < *sig && *buf && *buf != '\n') {
1184                 eol = strchrnul(buf, '\n');
1185                 if (*eol)
1186                         eol++;
1187                 buf = eol;
1188         }
1189         *sublen = buf - *sub;
1190         /* drop trailing newline, if present */
1191         if (*sublen && (*sub)[*sublen - 1] == '\n')
1192                 *sublen -= 1;
1193
1194         /* skip any empty lines */
1195         while (*buf == '\n')
1196                 buf++;
1197         *body = buf;
1198         *bodylen = strlen(buf);
1199         *nonsiglen = *sig - buf;
1200 }
1201
1202 /*
1203  * If 'lines' is greater than 0, append that many lines from the given
1204  * 'buf' of length 'size' to the given strbuf.
1205  */
1206 static void append_lines(struct strbuf *out, const char *buf, unsigned long size, int lines)
1207 {
1208         int i;
1209         const char *sp, *eol;
1210         size_t len;
1211
1212         sp = buf;
1213
1214         for (i = 0; i < lines && sp < buf + size; i++) {
1215                 if (i)
1216                         strbuf_addstr(out, "\n    ");
1217                 eol = memchr(sp, '\n', size - (sp - buf));
1218                 len = eol ? eol - sp : size - (sp - buf);
1219                 strbuf_add(out, sp, len);
1220                 if (!eol)
1221                         break;
1222                 sp = eol + 1;
1223         }
1224 }
1225
1226 /* See grab_values */
1227 static void grab_sub_body_contents(struct atom_value *val, int deref, void *buf)
1228 {
1229         int i;
1230         const char *subpos = NULL, *bodypos = NULL, *sigpos = NULL;
1231         unsigned long sublen = 0, bodylen = 0, nonsiglen = 0, siglen = 0;
1232
1233         for (i = 0; i < used_atom_cnt; i++) {
1234                 struct used_atom *atom = &used_atom[i];
1235                 const char *name = atom->name;
1236                 struct atom_value *v = &val[i];
1237                 if (!!deref != (*name == '*'))
1238                         continue;
1239                 if (deref)
1240                         name++;
1241                 if (strcmp(name, "subject") &&
1242                     strcmp(name, "body") &&
1243                     !starts_with(name, "trailers") &&
1244                     !starts_with(name, "contents"))
1245                         continue;
1246                 if (!subpos)
1247                         find_subpos(buf,
1248                                     &subpos, &sublen,
1249                                     &bodypos, &bodylen, &nonsiglen,
1250                                     &sigpos, &siglen);
1251
1252                 if (atom->u.contents.option == C_SUB)
1253                         v->s = copy_subject(subpos, sublen);
1254                 else if (atom->u.contents.option == C_BODY_DEP)
1255                         v->s = xmemdupz(bodypos, bodylen);
1256                 else if (atom->u.contents.option == C_BODY)
1257                         v->s = xmemdupz(bodypos, nonsiglen);
1258                 else if (atom->u.contents.option == C_SIG)
1259                         v->s = xmemdupz(sigpos, siglen);
1260                 else if (atom->u.contents.option == C_LINES) {
1261                         struct strbuf s = STRBUF_INIT;
1262                         const char *contents_end = bodylen + bodypos - siglen;
1263
1264                         /*  Size is the length of the message after removing the signature */
1265                         append_lines(&s, subpos, contents_end - subpos, atom->u.contents.nlines);
1266                         v->s = strbuf_detach(&s, NULL);
1267                 } else if (atom->u.contents.option == C_TRAILERS) {
1268                         struct strbuf s = STRBUF_INIT;
1269
1270                         /* Format the trailer info according to the trailer_opts given */
1271                         format_trailers_from_commit(&s, subpos, &atom->u.contents.trailer_opts);
1272
1273                         v->s = strbuf_detach(&s, NULL);
1274                 } else if (atom->u.contents.option == C_BARE)
1275                         v->s = xstrdup(subpos);
1276         }
1277 }
1278
1279 /*
1280  * We want to have empty print-string for field requests
1281  * that do not apply (e.g. "authordate" for a tag object)
1282  */
1283 static void fill_missing_values(struct atom_value *val)
1284 {
1285         int i;
1286         for (i = 0; i < used_atom_cnt; i++) {
1287                 struct atom_value *v = &val[i];
1288                 if (v->s == NULL)
1289                         v->s = xstrdup("");
1290         }
1291 }
1292
1293 /*
1294  * val is a list of atom_value to hold returned values.  Extract
1295  * the values for atoms in used_atom array out of (obj, buf, sz).
1296  * when deref is false, (obj, buf, sz) is the object that is
1297  * pointed at by the ref itself; otherwise it is the object the
1298  * ref (which is a tag) refers to.
1299  */
1300 static void grab_values(struct atom_value *val, int deref, struct object *obj, void *buf)
1301 {
1302         switch (obj->type) {
1303         case OBJ_TAG:
1304                 grab_tag_values(val, deref, obj);
1305                 grab_sub_body_contents(val, deref, buf);
1306                 grab_person("tagger", val, deref, buf);
1307                 break;
1308         case OBJ_COMMIT:
1309                 grab_commit_values(val, deref, obj);
1310                 grab_sub_body_contents(val, deref, buf);
1311                 grab_person("author", val, deref, buf);
1312                 grab_person("committer", val, deref, buf);
1313                 break;
1314         case OBJ_TREE:
1315                 /* grab_tree_values(val, deref, obj, buf, sz); */
1316                 break;
1317         case OBJ_BLOB:
1318                 /* grab_blob_values(val, deref, obj, buf, sz); */
1319                 break;
1320         default:
1321                 die("Eh?  Object of type %d?", obj->type);
1322         }
1323 }
1324
1325 static inline char *copy_advance(char *dst, const char *src)
1326 {
1327         while (*src)
1328                 *dst++ = *src++;
1329         return dst;
1330 }
1331
1332 static const char *lstrip_ref_components(const char *refname, int len)
1333 {
1334         long remaining = len;
1335         const char *start = xstrdup(refname);
1336         const char *to_free = start;
1337
1338         if (len < 0) {
1339                 int i;
1340                 const char *p = refname;
1341
1342                 /* Find total no of '/' separated path-components */
1343                 for (i = 0; p[i]; p[i] == '/' ? i++ : *p++)
1344                         ;
1345                 /*
1346                  * The number of components we need to strip is now
1347                  * the total minus the components to be left (Plus one
1348                  * because we count the number of '/', but the number
1349                  * of components is one more than the no of '/').
1350                  */
1351                 remaining = i + len + 1;
1352         }
1353
1354         while (remaining > 0) {
1355                 switch (*start++) {
1356                 case '\0':
1357                         free((char *)to_free);
1358                         return xstrdup("");
1359                 case '/':
1360                         remaining--;
1361                         break;
1362                 }
1363         }
1364
1365         start = xstrdup(start);
1366         free((char *)to_free);
1367         return start;
1368 }
1369
1370 static const char *rstrip_ref_components(const char *refname, int len)
1371 {
1372         long remaining = len;
1373         const char *start = xstrdup(refname);
1374         const char *to_free = start;
1375
1376         if (len < 0) {
1377                 int i;
1378                 const char *p = refname;
1379
1380                 /* Find total no of '/' separated path-components */
1381                 for (i = 0; p[i]; p[i] == '/' ? i++ : *p++)
1382                         ;
1383                 /*
1384                  * The number of components we need to strip is now
1385                  * the total minus the components to be left (Plus one
1386                  * because we count the number of '/', but the number
1387                  * of components is one more than the no of '/').
1388                  */
1389                 remaining = i + len + 1;
1390         }
1391
1392         while (remaining-- > 0) {
1393                 char *p = strrchr(start, '/');
1394                 if (p == NULL) {
1395                         free((char *)to_free);
1396                         return xstrdup("");
1397                 } else
1398                         p[0] = '\0';
1399         }
1400         return start;
1401 }
1402
1403 static const char *show_ref(struct refname_atom *atom, const char *refname)
1404 {
1405         if (atom->option == R_SHORT)
1406                 return shorten_unambiguous_ref(refname, warn_ambiguous_refs);
1407         else if (atom->option == R_LSTRIP)
1408                 return lstrip_ref_components(refname, atom->lstrip);
1409         else if (atom->option == R_RSTRIP)
1410                 return rstrip_ref_components(refname, atom->rstrip);
1411         else
1412                 return xstrdup(refname);
1413 }
1414
1415 static void fill_remote_ref_details(struct used_atom *atom, const char *refname,
1416                                     struct branch *branch, const char **s)
1417 {
1418         int num_ours, num_theirs;
1419         if (atom->u.remote_ref.option == RR_REF)
1420                 *s = show_ref(&atom->u.remote_ref.refname, refname);
1421         else if (atom->u.remote_ref.option == RR_TRACK) {
1422                 if (stat_tracking_info(branch, &num_ours, &num_theirs,
1423                                        NULL, atom->u.remote_ref.push,
1424                                        AHEAD_BEHIND_FULL) < 0) {
1425                         *s = xstrdup(msgs.gone);
1426                 } else if (!num_ours && !num_theirs)
1427                         *s = xstrdup("");
1428                 else if (!num_ours)
1429                         *s = xstrfmt(msgs.behind, num_theirs);
1430                 else if (!num_theirs)
1431                         *s = xstrfmt(msgs.ahead, num_ours);
1432                 else
1433                         *s = xstrfmt(msgs.ahead_behind,
1434                                      num_ours, num_theirs);
1435                 if (!atom->u.remote_ref.nobracket && *s[0]) {
1436                         const char *to_free = *s;
1437                         *s = xstrfmt("[%s]", *s);
1438                         free((void *)to_free);
1439                 }
1440         } else if (atom->u.remote_ref.option == RR_TRACKSHORT) {
1441                 if (stat_tracking_info(branch, &num_ours, &num_theirs,
1442                                        NULL, atom->u.remote_ref.push,
1443                                        AHEAD_BEHIND_FULL) < 0) {
1444                         *s = xstrdup("");
1445                         return;
1446                 }
1447                 if (!num_ours && !num_theirs)
1448                         *s = xstrdup("=");
1449                 else if (!num_ours)
1450                         *s = xstrdup("<");
1451                 else if (!num_theirs)
1452                         *s = xstrdup(">");
1453                 else
1454                         *s = xstrdup("<>");
1455         } else if (atom->u.remote_ref.option == RR_REMOTE_NAME) {
1456                 int explicit;
1457                 const char *remote = atom->u.remote_ref.push ?
1458                         pushremote_for_branch(branch, &explicit) :
1459                         remote_for_branch(branch, &explicit);
1460                 *s = xstrdup(explicit ? remote : "");
1461         } else if (atom->u.remote_ref.option == RR_REMOTE_REF) {
1462                 const char *merge;
1463
1464                 merge = remote_ref_for_branch(branch, atom->u.remote_ref.push);
1465                 *s = xstrdup(merge ? merge : "");
1466         } else
1467                 BUG("unhandled RR_* enum");
1468 }
1469
1470 char *get_head_description(void)
1471 {
1472         struct strbuf desc = STRBUF_INIT;
1473         struct wt_status_state state;
1474         memset(&state, 0, sizeof(state));
1475         wt_status_get_state(the_repository, &state, 1);
1476
1477         /*
1478          * The ( character must be hard-coded and not part of a localizable
1479          * string, since the description is used as a sort key and compared
1480          * with ref names.
1481          */
1482         strbuf_addch(&desc, '(');
1483         if (state.rebase_in_progress ||
1484             state.rebase_interactive_in_progress) {
1485                 if (state.branch)
1486                         strbuf_addf(&desc, _("no branch, rebasing %s"),
1487                                     state.branch);
1488                 else
1489                         strbuf_addf(&desc, _("no branch, rebasing detached HEAD %s"),
1490                                     state.detached_from);
1491         } else if (state.bisect_in_progress)
1492                 strbuf_addf(&desc, _("no branch, bisect started on %s"),
1493                             state.branch);
1494         else if (state.detached_from) {
1495                 if (state.detached_at)
1496                         strbuf_addstr(&desc, HEAD_DETACHED_AT);
1497                 else
1498                         strbuf_addstr(&desc, HEAD_DETACHED_FROM);
1499                 strbuf_addstr(&desc, state.detached_from);
1500         }
1501         else
1502                 strbuf_addstr(&desc, _("no branch"));
1503         strbuf_addch(&desc, ')');
1504
1505         free(state.branch);
1506         free(state.onto);
1507         free(state.detached_from);
1508         return strbuf_detach(&desc, NULL);
1509 }
1510
1511 static const char *get_symref(struct used_atom *atom, struct ref_array_item *ref)
1512 {
1513         if (!ref->symref)
1514                 return xstrdup("");
1515         else
1516                 return show_ref(&atom->u.refname, ref->symref);
1517 }
1518
1519 static const char *get_refname(struct used_atom *atom, struct ref_array_item *ref)
1520 {
1521         if (ref->kind & FILTER_REFS_DETACHED_HEAD)
1522                 return get_head_description();
1523         return show_ref(&atom->u.refname, ref->refname);
1524 }
1525
1526 static int get_object(struct ref_array_item *ref, int deref, struct object **obj,
1527                       struct expand_data *oi, struct strbuf *err)
1528 {
1529         /* parse_object_buffer() will set eaten to 0 if free() will be needed */
1530         int eaten = 1;
1531         if (oi->info.contentp) {
1532                 /* We need to know that to use parse_object_buffer properly */
1533                 oi->info.sizep = &oi->size;
1534                 oi->info.typep = &oi->type;
1535         }
1536         if (oid_object_info_extended(the_repository, &oi->oid, &oi->info,
1537                                      OBJECT_INFO_LOOKUP_REPLACE))
1538                 return strbuf_addf_ret(err, -1, _("missing object %s for %s"),
1539                                        oid_to_hex(&oi->oid), ref->refname);
1540         if (oi->info.disk_sizep && oi->disk_size < 0)
1541                 BUG("Object size is less than zero.");
1542
1543         if (oi->info.contentp) {
1544                 *obj = parse_object_buffer(the_repository, &oi->oid, oi->type, oi->size, oi->content, &eaten);
1545                 if (!obj) {
1546                         if (!eaten)
1547                                 free(oi->content);
1548                         return strbuf_addf_ret(err, -1, _("parse_object_buffer failed on %s for %s"),
1549                                                oid_to_hex(&oi->oid), ref->refname);
1550                 }
1551                 grab_values(ref->value, deref, *obj, oi->content);
1552         }
1553
1554         grab_common_values(ref->value, deref, oi);
1555         if (!eaten)
1556                 free(oi->content);
1557         return 0;
1558 }
1559
1560 static void populate_worktree_map(struct hashmap *map, struct worktree **worktrees)
1561 {
1562         int i;
1563
1564         for (i = 0; worktrees[i]; i++) {
1565                 if (worktrees[i]->head_ref) {
1566                         struct ref_to_worktree_entry *entry;
1567                         entry = xmalloc(sizeof(*entry));
1568                         entry->wt = worktrees[i];
1569                         hashmap_entry_init(&entry->ent,
1570                                         strhash(worktrees[i]->head_ref));
1571
1572                         hashmap_add(map, &entry->ent);
1573                 }
1574         }
1575 }
1576
1577 static void lazy_init_worktree_map(void)
1578 {
1579         if (ref_to_worktree_map.worktrees)
1580                 return;
1581
1582         ref_to_worktree_map.worktrees = get_worktrees(0);
1583         hashmap_init(&(ref_to_worktree_map.map), ref_to_worktree_map_cmpfnc, NULL, 0);
1584         populate_worktree_map(&(ref_to_worktree_map.map), ref_to_worktree_map.worktrees);
1585 }
1586
1587 static char *get_worktree_path(const struct used_atom *atom, const struct ref_array_item *ref)
1588 {
1589         struct hashmap_entry entry, *e;
1590         struct ref_to_worktree_entry *lookup_result;
1591
1592         lazy_init_worktree_map();
1593
1594         hashmap_entry_init(&entry, strhash(ref->refname));
1595         e = hashmap_get(&(ref_to_worktree_map.map), &entry, ref->refname);
1596
1597         if (!e)
1598                 return xstrdup("");
1599
1600         lookup_result = container_of(e, struct ref_to_worktree_entry, ent);
1601
1602         return xstrdup(lookup_result->wt->path);
1603 }
1604
1605 /*
1606  * Parse the object referred by ref, and grab needed value.
1607  */
1608 static int populate_value(struct ref_array_item *ref, struct strbuf *err)
1609 {
1610         struct object *obj;
1611         int i;
1612         struct object_info empty = OBJECT_INFO_INIT;
1613
1614         ref->value = xcalloc(used_atom_cnt, sizeof(struct atom_value));
1615
1616         if (need_symref && (ref->flag & REF_ISSYMREF) && !ref->symref) {
1617                 ref->symref = resolve_refdup(ref->refname, RESOLVE_REF_READING,
1618                                              NULL, NULL);
1619                 if (!ref->symref)
1620                         ref->symref = xstrdup("");
1621         }
1622
1623         /* Fill in specials first */
1624         for (i = 0; i < used_atom_cnt; i++) {
1625                 struct used_atom *atom = &used_atom[i];
1626                 const char *name = used_atom[i].name;
1627                 struct atom_value *v = &ref->value[i];
1628                 int deref = 0;
1629                 const char *refname;
1630                 struct branch *branch = NULL;
1631
1632                 v->handler = append_atom;
1633                 v->atom = atom;
1634
1635                 if (*name == '*') {
1636                         deref = 1;
1637                         name++;
1638                 }
1639
1640                 if (starts_with(name, "refname"))
1641                         refname = get_refname(atom, ref);
1642                 else if (!strcmp(name, "worktreepath")) {
1643                         if (ref->kind == FILTER_REFS_BRANCHES)
1644                                 v->s = get_worktree_path(atom, ref);
1645                         else
1646                                 v->s = xstrdup("");
1647                         continue;
1648                 }
1649                 else if (starts_with(name, "symref"))
1650                         refname = get_symref(atom, ref);
1651                 else if (starts_with(name, "upstream")) {
1652                         const char *branch_name;
1653                         /* only local branches may have an upstream */
1654                         if (!skip_prefix(ref->refname, "refs/heads/",
1655                                          &branch_name)) {
1656                                 v->s = xstrdup("");
1657                                 continue;
1658                         }
1659                         branch = branch_get(branch_name);
1660
1661                         refname = branch_get_upstream(branch, NULL);
1662                         if (refname)
1663                                 fill_remote_ref_details(atom, refname, branch, &v->s);
1664                         else
1665                                 v->s = xstrdup("");
1666                         continue;
1667                 } else if (atom->u.remote_ref.push) {
1668                         const char *branch_name;
1669                         v->s = xstrdup("");
1670                         if (!skip_prefix(ref->refname, "refs/heads/",
1671                                          &branch_name))
1672                                 continue;
1673                         branch = branch_get(branch_name);
1674
1675                         if (atom->u.remote_ref.push_remote)
1676                                 refname = NULL;
1677                         else {
1678                                 refname = branch_get_push(branch, NULL);
1679                                 if (!refname)
1680                                         continue;
1681                         }
1682                         /* We will definitely re-init v->s on the next line. */
1683                         free((char *)v->s);
1684                         fill_remote_ref_details(atom, refname, branch, &v->s);
1685                         continue;
1686                 } else if (starts_with(name, "color:")) {
1687                         v->s = xstrdup(atom->u.color);
1688                         continue;
1689                 } else if (!strcmp(name, "flag")) {
1690                         char buf[256], *cp = buf;
1691                         if (ref->flag & REF_ISSYMREF)
1692                                 cp = copy_advance(cp, ",symref");
1693                         if (ref->flag & REF_ISPACKED)
1694                                 cp = copy_advance(cp, ",packed");
1695                         if (cp == buf)
1696                                 v->s = xstrdup("");
1697                         else {
1698                                 *cp = '\0';
1699                                 v->s = xstrdup(buf + 1);
1700                         }
1701                         continue;
1702                 } else if (!deref && grab_objectname(name, &ref->objectname, v, atom)) {
1703                         continue;
1704                 } else if (!strcmp(name, "HEAD")) {
1705                         if (atom->u.head && !strcmp(ref->refname, atom->u.head))
1706                                 v->s = xstrdup("*");
1707                         else
1708                                 v->s = xstrdup(" ");
1709                         continue;
1710                 } else if (starts_with(name, "align")) {
1711                         v->handler = align_atom_handler;
1712                         v->s = xstrdup("");
1713                         continue;
1714                 } else if (!strcmp(name, "end")) {
1715                         v->handler = end_atom_handler;
1716                         v->s = xstrdup("");
1717                         continue;
1718                 } else if (starts_with(name, "if")) {
1719                         const char *s;
1720                         if (skip_prefix(name, "if:", &s))
1721                                 v->s = xstrdup(s);
1722                         else
1723                                 v->s = xstrdup("");
1724                         v->handler = if_atom_handler;
1725                         continue;
1726                 } else if (!strcmp(name, "then")) {
1727                         v->handler = then_atom_handler;
1728                         v->s = xstrdup("");
1729                         continue;
1730                 } else if (!strcmp(name, "else")) {
1731                         v->handler = else_atom_handler;
1732                         v->s = xstrdup("");
1733                         continue;
1734                 } else
1735                         continue;
1736
1737                 if (!deref)
1738                         v->s = xstrdup(refname);
1739                 else
1740                         v->s = xstrfmt("%s^{}", refname);
1741                 free((char *)refname);
1742         }
1743
1744         for (i = 0; i < used_atom_cnt; i++) {
1745                 struct atom_value *v = &ref->value[i];
1746                 if (v->s == NULL && used_atom[i].source == SOURCE_NONE)
1747                         return strbuf_addf_ret(err, -1, _("missing object %s for %s"),
1748                                                oid_to_hex(&ref->objectname), ref->refname);
1749         }
1750
1751         if (need_tagged)
1752                 oi.info.contentp = &oi.content;
1753         if (!memcmp(&oi.info, &empty, sizeof(empty)) &&
1754             !memcmp(&oi_deref.info, &empty, sizeof(empty)))
1755                 return 0;
1756
1757
1758         oi.oid = ref->objectname;
1759         if (get_object(ref, 0, &obj, &oi, err))
1760                 return -1;
1761
1762         /*
1763          * If there is no atom that wants to know about tagged
1764          * object, we are done.
1765          */
1766         if (!need_tagged || (obj->type != OBJ_TAG))
1767                 return 0;
1768
1769         /*
1770          * If it is a tag object, see if we use a value that derefs
1771          * the object, and if we do grab the object it refers to.
1772          */
1773         oi_deref.oid = *get_tagged_oid((struct tag *)obj);
1774
1775         /*
1776          * NEEDSWORK: This derefs tag only once, which
1777          * is good to deal with chains of trust, but
1778          * is not consistent with what deref_tag() does
1779          * which peels the onion to the core.
1780          */
1781         return get_object(ref, 1, &obj, &oi_deref, err);
1782 }
1783
1784 /*
1785  * Given a ref, return the value for the atom.  This lazily gets value
1786  * out of the object by calling populate value.
1787  */
1788 static int get_ref_atom_value(struct ref_array_item *ref, int atom,
1789                               struct atom_value **v, struct strbuf *err)
1790 {
1791         if (!ref->value) {
1792                 if (populate_value(ref, err))
1793                         return -1;
1794                 fill_missing_values(ref->value);
1795         }
1796         *v = &ref->value[atom];
1797         return 0;
1798 }
1799
1800 /*
1801  * Return 1 if the refname matches one of the patterns, otherwise 0.
1802  * A pattern can be a literal prefix (e.g. a refname "refs/heads/master"
1803  * matches a pattern "refs/heads/mas") or a wildcard (e.g. the same ref
1804  * matches "refs/heads/mas*", too).
1805  */
1806 static int match_pattern(const struct ref_filter *filter, const char *refname)
1807 {
1808         const char **patterns = filter->name_patterns;
1809         unsigned flags = 0;
1810
1811         if (filter->ignore_case)
1812                 flags |= WM_CASEFOLD;
1813
1814         /*
1815          * When no '--format' option is given we need to skip the prefix
1816          * for matching refs of tags and branches.
1817          */
1818         (void)(skip_prefix(refname, "refs/tags/", &refname) ||
1819                skip_prefix(refname, "refs/heads/", &refname) ||
1820                skip_prefix(refname, "refs/remotes/", &refname) ||
1821                skip_prefix(refname, "refs/", &refname));
1822
1823         for (; *patterns; patterns++) {
1824                 if (!wildmatch(*patterns, refname, flags))
1825                         return 1;
1826         }
1827         return 0;
1828 }
1829
1830 /*
1831  * Return 1 if the refname matches one of the patterns, otherwise 0.
1832  * A pattern can be path prefix (e.g. a refname "refs/heads/master"
1833  * matches a pattern "refs/heads/" but not "refs/heads/m") or a
1834  * wildcard (e.g. the same ref matches "refs/heads/m*", too).
1835  */
1836 static int match_name_as_path(const struct ref_filter *filter, const char *refname)
1837 {
1838         const char **pattern = filter->name_patterns;
1839         int namelen = strlen(refname);
1840         unsigned flags = WM_PATHNAME;
1841
1842         if (filter->ignore_case)
1843                 flags |= WM_CASEFOLD;
1844
1845         for (; *pattern; pattern++) {
1846                 const char *p = *pattern;
1847                 int plen = strlen(p);
1848
1849                 if ((plen <= namelen) &&
1850                     !strncmp(refname, p, plen) &&
1851                     (refname[plen] == '\0' ||
1852                      refname[plen] == '/' ||
1853                      p[plen-1] == '/'))
1854                         return 1;
1855                 if (!wildmatch(p, refname, flags))
1856                         return 1;
1857         }
1858         return 0;
1859 }
1860
1861 /* Return 1 if the refname matches one of the patterns, otherwise 0. */
1862 static int filter_pattern_match(struct ref_filter *filter, const char *refname)
1863 {
1864         if (!*filter->name_patterns)
1865                 return 1; /* No pattern always matches */
1866         if (filter->match_as_path)
1867                 return match_name_as_path(filter, refname);
1868         return match_pattern(filter, refname);
1869 }
1870
1871 static int qsort_strcmp(const void *va, const void *vb)
1872 {
1873         const char *a = *(const char **)va;
1874         const char *b = *(const char **)vb;
1875
1876         return strcmp(a, b);
1877 }
1878
1879 static void find_longest_prefixes_1(struct string_list *out,
1880                                   struct strbuf *prefix,
1881                                   const char **patterns, size_t nr)
1882 {
1883         size_t i;
1884
1885         for (i = 0; i < nr; i++) {
1886                 char c = patterns[i][prefix->len];
1887                 if (!c || is_glob_special(c)) {
1888                         string_list_append(out, prefix->buf);
1889                         return;
1890                 }
1891         }
1892
1893         i = 0;
1894         while (i < nr) {
1895                 size_t end;
1896
1897                 /*
1898                 * Set "end" to the index of the element _after_ the last one
1899                 * in our group.
1900                 */
1901                 for (end = i + 1; end < nr; end++) {
1902                         if (patterns[i][prefix->len] != patterns[end][prefix->len])
1903                                 break;
1904                 }
1905
1906                 strbuf_addch(prefix, patterns[i][prefix->len]);
1907                 find_longest_prefixes_1(out, prefix, patterns + i, end - i);
1908                 strbuf_setlen(prefix, prefix->len - 1);
1909
1910                 i = end;
1911         }
1912 }
1913
1914 static void find_longest_prefixes(struct string_list *out,
1915                                   const char **patterns)
1916 {
1917         struct argv_array sorted = ARGV_ARRAY_INIT;
1918         struct strbuf prefix = STRBUF_INIT;
1919
1920         argv_array_pushv(&sorted, patterns);
1921         QSORT(sorted.argv, sorted.argc, qsort_strcmp);
1922
1923         find_longest_prefixes_1(out, &prefix, sorted.argv, sorted.argc);
1924
1925         argv_array_clear(&sorted);
1926         strbuf_release(&prefix);
1927 }
1928
1929 /*
1930  * This is the same as for_each_fullref_in(), but it tries to iterate
1931  * only over the patterns we'll care about. Note that it _doesn't_ do a full
1932  * pattern match, so the callback still has to match each ref individually.
1933  */
1934 static int for_each_fullref_in_pattern(struct ref_filter *filter,
1935                                        each_ref_fn cb,
1936                                        void *cb_data,
1937                                        int broken)
1938 {
1939         struct string_list prefixes = STRING_LIST_INIT_DUP;
1940         struct string_list_item *prefix;
1941         int ret;
1942
1943         if (!filter->match_as_path) {
1944                 /*
1945                  * in this case, the patterns are applied after
1946                  * prefixes like "refs/heads/" etc. are stripped off,
1947                  * so we have to look at everything:
1948                  */
1949                 return for_each_fullref_in("", cb, cb_data, broken);
1950         }
1951
1952         if (filter->ignore_case) {
1953                 /*
1954                  * we can't handle case-insensitive comparisons,
1955                  * so just return everything and let the caller
1956                  * sort it out.
1957                  */
1958                 return for_each_fullref_in("", cb, cb_data, broken);
1959         }
1960
1961         if (!filter->name_patterns[0]) {
1962                 /* no patterns; we have to look at everything */
1963                 return for_each_fullref_in("", cb, cb_data, broken);
1964         }
1965
1966         find_longest_prefixes(&prefixes, filter->name_patterns);
1967
1968         for_each_string_list_item(prefix, &prefixes) {
1969                 ret = for_each_fullref_in(prefix->string, cb, cb_data, broken);
1970                 if (ret)
1971                         break;
1972         }
1973
1974         string_list_clear(&prefixes, 0);
1975         return ret;
1976 }
1977
1978 /*
1979  * Given a ref (oid, refname), check if the ref belongs to the array
1980  * of oids. If the given ref is a tag, check if the given tag points
1981  * at one of the oids in the given oid array.
1982  * NEEDSWORK:
1983  * 1. Only a single level of inderection is obtained, we might want to
1984  * change this to account for multiple levels (e.g. annotated tags
1985  * pointing to annotated tags pointing to a commit.)
1986  * 2. As the refs are cached we might know what refname peels to without
1987  * the need to parse the object via parse_object(). peel_ref() might be a
1988  * more efficient alternative to obtain the pointee.
1989  */
1990 static const struct object_id *match_points_at(struct oid_array *points_at,
1991                                                const struct object_id *oid,
1992                                                const char *refname)
1993 {
1994         const struct object_id *tagged_oid = NULL;
1995         struct object *obj;
1996
1997         if (oid_array_lookup(points_at, oid) >= 0)
1998                 return oid;
1999         obj = parse_object(the_repository, oid);
2000         if (!obj)
2001                 die(_("malformed object at '%s'"), refname);
2002         if (obj->type == OBJ_TAG)
2003                 tagged_oid = get_tagged_oid((struct tag *)obj);
2004         if (tagged_oid && oid_array_lookup(points_at, tagged_oid) >= 0)
2005                 return tagged_oid;
2006         return NULL;
2007 }
2008
2009 /*
2010  * Allocate space for a new ref_array_item and copy the name and oid to it.
2011  *
2012  * Callers can then fill in other struct members at their leisure.
2013  */
2014 static struct ref_array_item *new_ref_array_item(const char *refname,
2015                                                  const struct object_id *oid)
2016 {
2017         struct ref_array_item *ref;
2018
2019         FLEX_ALLOC_STR(ref, refname, refname);
2020         oidcpy(&ref->objectname, oid);
2021
2022         return ref;
2023 }
2024
2025 struct ref_array_item *ref_array_push(struct ref_array *array,
2026                                       const char *refname,
2027                                       const struct object_id *oid)
2028 {
2029         struct ref_array_item *ref = new_ref_array_item(refname, oid);
2030
2031         ALLOC_GROW(array->items, array->nr + 1, array->alloc);
2032         array->items[array->nr++] = ref;
2033
2034         return ref;
2035 }
2036
2037 static int ref_kind_from_refname(const char *refname)
2038 {
2039         unsigned int i;
2040
2041         static struct {
2042                 const char *prefix;
2043                 unsigned int kind;
2044         } ref_kind[] = {
2045                 { "refs/heads/" , FILTER_REFS_BRANCHES },
2046                 { "refs/remotes/" , FILTER_REFS_REMOTES },
2047                 { "refs/tags/", FILTER_REFS_TAGS}
2048         };
2049
2050         if (!strcmp(refname, "HEAD"))
2051                 return FILTER_REFS_DETACHED_HEAD;
2052
2053         for (i = 0; i < ARRAY_SIZE(ref_kind); i++) {
2054                 if (starts_with(refname, ref_kind[i].prefix))
2055                         return ref_kind[i].kind;
2056         }
2057
2058         return FILTER_REFS_OTHERS;
2059 }
2060
2061 static int filter_ref_kind(struct ref_filter *filter, const char *refname)
2062 {
2063         if (filter->kind == FILTER_REFS_BRANCHES ||
2064             filter->kind == FILTER_REFS_REMOTES ||
2065             filter->kind == FILTER_REFS_TAGS)
2066                 return filter->kind;
2067         return ref_kind_from_refname(refname);
2068 }
2069
2070 struct ref_filter_cbdata {
2071         struct ref_array *array;
2072         struct ref_filter *filter;
2073         struct contains_cache contains_cache;
2074         struct contains_cache no_contains_cache;
2075 };
2076
2077 /*
2078  * A call-back given to for_each_ref().  Filter refs and keep them for
2079  * later object processing.
2080  */
2081 static int ref_filter_handler(const char *refname, const struct object_id *oid, int flag, void *cb_data)
2082 {
2083         struct ref_filter_cbdata *ref_cbdata = cb_data;
2084         struct ref_filter *filter = ref_cbdata->filter;
2085         struct ref_array_item *ref;
2086         struct commit *commit = NULL;
2087         unsigned int kind;
2088
2089         if (flag & REF_BAD_NAME) {
2090                 warning(_("ignoring ref with broken name %s"), refname);
2091                 return 0;
2092         }
2093
2094         if (flag & REF_ISBROKEN) {
2095                 warning(_("ignoring broken ref %s"), refname);
2096                 return 0;
2097         }
2098
2099         /* Obtain the current ref kind from filter_ref_kind() and ignore unwanted refs. */
2100         kind = filter_ref_kind(filter, refname);
2101         if (!(kind & filter->kind))
2102                 return 0;
2103
2104         if (!filter_pattern_match(filter, refname))
2105                 return 0;
2106
2107         if (filter->points_at.nr && !match_points_at(&filter->points_at, oid, refname))
2108                 return 0;
2109
2110         /*
2111          * A merge filter is applied on refs pointing to commits. Hence
2112          * obtain the commit using the 'oid' available and discard all
2113          * non-commits early. The actual filtering is done later.
2114          */
2115         if (filter->merge_commit || filter->with_commit || filter->no_commit || filter->verbose) {
2116                 commit = lookup_commit_reference_gently(the_repository, oid,
2117                                                         1);
2118                 if (!commit)
2119                         return 0;
2120                 /* We perform the filtering for the '--contains' option... */
2121                 if (filter->with_commit &&
2122                     !commit_contains(filter, commit, filter->with_commit, &ref_cbdata->contains_cache))
2123                         return 0;
2124                 /* ...or for the `--no-contains' option */
2125                 if (filter->no_commit &&
2126                     commit_contains(filter, commit, filter->no_commit, &ref_cbdata->no_contains_cache))
2127                         return 0;
2128         }
2129
2130         /*
2131          * We do not open the object yet; sort may only need refname
2132          * to do its job and the resulting list may yet to be pruned
2133          * by maxcount logic.
2134          */
2135         ref = ref_array_push(ref_cbdata->array, refname, oid);
2136         ref->commit = commit;
2137         ref->flag = flag;
2138         ref->kind = kind;
2139
2140         return 0;
2141 }
2142
2143 /*  Free memory allocated for a ref_array_item */
2144 static void free_array_item(struct ref_array_item *item)
2145 {
2146         free((char *)item->symref);
2147         if (item->value) {
2148                 int i;
2149                 for (i = 0; i < used_atom_cnt; i++)
2150                         free((char *)item->value[i].s);
2151                 free(item->value);
2152         }
2153         free(item);
2154 }
2155
2156 /* Free all memory allocated for ref_array */
2157 void ref_array_clear(struct ref_array *array)
2158 {
2159         int i;
2160
2161         for (i = 0; i < array->nr; i++)
2162                 free_array_item(array->items[i]);
2163         FREE_AND_NULL(array->items);
2164         array->nr = array->alloc = 0;
2165
2166         for (i = 0; i < used_atom_cnt; i++)
2167                 free((char *)used_atom[i].name);
2168         FREE_AND_NULL(used_atom);
2169         used_atom_cnt = 0;
2170
2171         if (ref_to_worktree_map.worktrees) {
2172                 hashmap_free_entries(&(ref_to_worktree_map.map),
2173                                         struct ref_to_worktree_entry, ent);
2174                 free_worktrees(ref_to_worktree_map.worktrees);
2175                 ref_to_worktree_map.worktrees = NULL;
2176         }
2177 }
2178
2179 static void do_merge_filter(struct ref_filter_cbdata *ref_cbdata)
2180 {
2181         struct rev_info revs;
2182         int i, old_nr;
2183         struct ref_filter *filter = ref_cbdata->filter;
2184         struct ref_array *array = ref_cbdata->array;
2185         struct commit **to_clear = xcalloc(sizeof(struct commit *), array->nr);
2186
2187         repo_init_revisions(the_repository, &revs, NULL);
2188
2189         for (i = 0; i < array->nr; i++) {
2190                 struct ref_array_item *item = array->items[i];
2191                 add_pending_object(&revs, &item->commit->object, item->refname);
2192                 to_clear[i] = item->commit;
2193         }
2194
2195         filter->merge_commit->object.flags |= UNINTERESTING;
2196         add_pending_object(&revs, &filter->merge_commit->object, "");
2197
2198         revs.limited = 1;
2199         if (prepare_revision_walk(&revs))
2200                 die(_("revision walk setup failed"));
2201
2202         old_nr = array->nr;
2203         array->nr = 0;
2204
2205         for (i = 0; i < old_nr; i++) {
2206                 struct ref_array_item *item = array->items[i];
2207                 struct commit *commit = item->commit;
2208
2209                 int is_merged = !!(commit->object.flags & UNINTERESTING);
2210
2211                 if (is_merged == (filter->merge == REF_FILTER_MERGED_INCLUDE))
2212                         array->items[array->nr++] = array->items[i];
2213                 else
2214                         free_array_item(item);
2215         }
2216
2217         clear_commit_marks_many(old_nr, to_clear, ALL_REV_FLAGS);
2218         clear_commit_marks(filter->merge_commit, ALL_REV_FLAGS);
2219         free(to_clear);
2220 }
2221
2222 /*
2223  * API for filtering a set of refs. Based on the type of refs the user
2224  * has requested, we iterate through those refs and apply filters
2225  * as per the given ref_filter structure and finally store the
2226  * filtered refs in the ref_array structure.
2227  */
2228 int filter_refs(struct ref_array *array, struct ref_filter *filter, unsigned int type)
2229 {
2230         struct ref_filter_cbdata ref_cbdata;
2231         int ret = 0;
2232         unsigned int broken = 0;
2233
2234         ref_cbdata.array = array;
2235         ref_cbdata.filter = filter;
2236
2237         if (type & FILTER_REFS_INCLUDE_BROKEN)
2238                 broken = 1;
2239         filter->kind = type & FILTER_REFS_KIND_MASK;
2240
2241         init_contains_cache(&ref_cbdata.contains_cache);
2242         init_contains_cache(&ref_cbdata.no_contains_cache);
2243
2244         /*  Simple per-ref filtering */
2245         if (!filter->kind)
2246                 die("filter_refs: invalid type");
2247         else {
2248                 /*
2249                  * For common cases where we need only branches or remotes or tags,
2250                  * we only iterate through those refs. If a mix of refs is needed,
2251                  * we iterate over all refs and filter out required refs with the help
2252                  * of filter_ref_kind().
2253                  */
2254                 if (filter->kind == FILTER_REFS_BRANCHES)
2255                         ret = for_each_fullref_in("refs/heads/", ref_filter_handler, &ref_cbdata, broken);
2256                 else if (filter->kind == FILTER_REFS_REMOTES)
2257                         ret = for_each_fullref_in("refs/remotes/", ref_filter_handler, &ref_cbdata, broken);
2258                 else if (filter->kind == FILTER_REFS_TAGS)
2259                         ret = for_each_fullref_in("refs/tags/", ref_filter_handler, &ref_cbdata, broken);
2260                 else if (filter->kind & FILTER_REFS_ALL)
2261                         ret = for_each_fullref_in_pattern(filter, ref_filter_handler, &ref_cbdata, broken);
2262                 if (!ret && (filter->kind & FILTER_REFS_DETACHED_HEAD))
2263                         head_ref(ref_filter_handler, &ref_cbdata);
2264         }
2265
2266         clear_contains_cache(&ref_cbdata.contains_cache);
2267         clear_contains_cache(&ref_cbdata.no_contains_cache);
2268
2269         /*  Filters that need revision walking */
2270         if (filter->merge_commit)
2271                 do_merge_filter(&ref_cbdata);
2272
2273         return ret;
2274 }
2275
2276 static int cmp_ref_sorting(struct ref_sorting *s, struct ref_array_item *a, struct ref_array_item *b)
2277 {
2278         struct atom_value *va, *vb;
2279         int cmp;
2280         cmp_type cmp_type = used_atom[s->atom].type;
2281         int (*cmp_fn)(const char *, const char *);
2282         struct strbuf err = STRBUF_INIT;
2283
2284         if (get_ref_atom_value(a, s->atom, &va, &err))
2285                 die("%s", err.buf);
2286         if (get_ref_atom_value(b, s->atom, &vb, &err))
2287                 die("%s", err.buf);
2288         strbuf_release(&err);
2289         cmp_fn = s->ignore_case ? strcasecmp : strcmp;
2290         if (s->version)
2291                 cmp = versioncmp(va->s, vb->s);
2292         else if (cmp_type == FIELD_STR)
2293                 cmp = cmp_fn(va->s, vb->s);
2294         else {
2295                 if (va->value < vb->value)
2296                         cmp = -1;
2297                 else if (va->value == vb->value)
2298                         cmp = 0;
2299                 else
2300                         cmp = 1;
2301         }
2302
2303         return (s->reverse) ? -cmp : cmp;
2304 }
2305
2306 static int compare_refs(const void *a_, const void *b_, void *ref_sorting)
2307 {
2308         struct ref_array_item *a = *((struct ref_array_item **)a_);
2309         struct ref_array_item *b = *((struct ref_array_item **)b_);
2310         struct ref_sorting *s;
2311
2312         for (s = ref_sorting; s; s = s->next) {
2313                 int cmp = cmp_ref_sorting(s, a, b);
2314                 if (cmp)
2315                         return cmp;
2316         }
2317         s = ref_sorting;
2318         return s && s->ignore_case ?
2319                 strcasecmp(a->refname, b->refname) :
2320                 strcmp(a->refname, b->refname);
2321 }
2322
2323 void ref_sorting_icase_all(struct ref_sorting *sorting, int flag)
2324 {
2325         for (; sorting; sorting = sorting->next)
2326                 sorting->ignore_case = !!flag;
2327 }
2328
2329 void ref_array_sort(struct ref_sorting *sorting, struct ref_array *array)
2330 {
2331         QSORT_S(array->items, array->nr, compare_refs, sorting);
2332 }
2333
2334 static void append_literal(const char *cp, const char *ep, struct ref_formatting_state *state)
2335 {
2336         struct strbuf *s = &state->stack->output;
2337
2338         while (*cp && (!ep || cp < ep)) {
2339                 if (*cp == '%') {
2340                         if (cp[1] == '%')
2341                                 cp++;
2342                         else {
2343                                 int ch = hex2chr(cp + 1);
2344                                 if (0 <= ch) {
2345                                         strbuf_addch(s, ch);
2346                                         cp += 3;
2347                                         continue;
2348                                 }
2349                         }
2350                 }
2351                 strbuf_addch(s, *cp);
2352                 cp++;
2353         }
2354 }
2355
2356 int format_ref_array_item(struct ref_array_item *info,
2357                            const struct ref_format *format,
2358                            struct strbuf *final_buf,
2359                            struct strbuf *error_buf)
2360 {
2361         const char *cp, *sp, *ep;
2362         struct ref_formatting_state state = REF_FORMATTING_STATE_INIT;
2363
2364         state.quote_style = format->quote_style;
2365         push_stack_element(&state.stack);
2366
2367         for (cp = format->format; *cp && (sp = find_next(cp)); cp = ep + 1) {
2368                 struct atom_value *atomv;
2369                 int pos;
2370
2371                 ep = strchr(sp, ')');
2372                 if (cp < sp)
2373                         append_literal(cp, sp, &state);
2374                 pos = parse_ref_filter_atom(format, sp + 2, ep, error_buf);
2375                 if (pos < 0 || get_ref_atom_value(info, pos, &atomv, error_buf) ||
2376                     atomv->handler(atomv, &state, error_buf)) {
2377                         pop_stack_element(&state.stack);
2378                         return -1;
2379                 }
2380         }
2381         if (*cp) {
2382                 sp = cp + strlen(cp);
2383                 append_literal(cp, sp, &state);
2384         }
2385         if (format->need_color_reset_at_eol) {
2386                 struct atom_value resetv;
2387                 resetv.s = GIT_COLOR_RESET;
2388                 if (append_atom(&resetv, &state, error_buf)) {
2389                         pop_stack_element(&state.stack);
2390                         return -1;
2391                 }
2392         }
2393         if (state.stack->prev) {
2394                 pop_stack_element(&state.stack);
2395                 return strbuf_addf_ret(error_buf, -1, _("format: %%(end) atom missing"));
2396         }
2397         strbuf_addbuf(final_buf, &state.stack->output);
2398         pop_stack_element(&state.stack);
2399         return 0;
2400 }
2401
2402 void show_ref_array_item(struct ref_array_item *info,
2403                          const struct ref_format *format)
2404 {
2405         struct strbuf final_buf = STRBUF_INIT;
2406         struct strbuf error_buf = STRBUF_INIT;
2407
2408         if (format_ref_array_item(info, format, &final_buf, &error_buf))
2409                 die("%s", error_buf.buf);
2410         fwrite(final_buf.buf, 1, final_buf.len, stdout);
2411         strbuf_release(&error_buf);
2412         strbuf_release(&final_buf);
2413         putchar('\n');
2414 }
2415
2416 void pretty_print_ref(const char *name, const struct object_id *oid,
2417                       const struct ref_format *format)
2418 {
2419         struct ref_array_item *ref_item;
2420         ref_item = new_ref_array_item(name, oid);
2421         ref_item->kind = ref_kind_from_refname(name);
2422         show_ref_array_item(ref_item, format);
2423         free_array_item(ref_item);
2424 }
2425
2426 static int parse_sorting_atom(const char *atom)
2427 {
2428         /*
2429          * This parses an atom using a dummy ref_format, since we don't
2430          * actually care about the formatting details.
2431          */
2432         struct ref_format dummy = REF_FORMAT_INIT;
2433         const char *end = atom + strlen(atom);
2434         struct strbuf err = STRBUF_INIT;
2435         int res = parse_ref_filter_atom(&dummy, atom, end, &err);
2436         if (res < 0)
2437                 die("%s", err.buf);
2438         strbuf_release(&err);
2439         return res;
2440 }
2441
2442 /*  If no sorting option is given, use refname to sort as default */
2443 struct ref_sorting *ref_default_sorting(void)
2444 {
2445         static const char cstr_name[] = "refname";
2446
2447         struct ref_sorting *sorting = xcalloc(1, sizeof(*sorting));
2448
2449         sorting->next = NULL;
2450         sorting->atom = parse_sorting_atom(cstr_name);
2451         return sorting;
2452 }
2453
2454 void parse_ref_sorting(struct ref_sorting **sorting_tail, const char *arg)
2455 {
2456         struct ref_sorting *s;
2457
2458         s = xcalloc(1, sizeof(*s));
2459         s->next = *sorting_tail;
2460         *sorting_tail = s;
2461
2462         if (*arg == '-') {
2463                 s->reverse = 1;
2464                 arg++;
2465         }
2466         if (skip_prefix(arg, "version:", &arg) ||
2467             skip_prefix(arg, "v:", &arg))
2468                 s->version = 1;
2469         s->atom = parse_sorting_atom(arg);
2470 }
2471
2472 int parse_opt_ref_sorting(const struct option *opt, const char *arg, int unset)
2473 {
2474         /*
2475          * NEEDSWORK: We should probably clear the list in this case, but we've
2476          * already munged the global used_atoms list, which would need to be
2477          * undone.
2478          */
2479         BUG_ON_OPT_NEG(unset);
2480
2481         parse_ref_sorting(opt->value, arg);
2482         return 0;
2483 }
2484
2485 int parse_opt_merge_filter(const struct option *opt, const char *arg, int unset)
2486 {
2487         struct ref_filter *rf = opt->value;
2488         struct object_id oid;
2489         int no_merged = starts_with(opt->long_name, "no");
2490
2491         BUG_ON_OPT_NEG(unset);
2492
2493         if (rf->merge) {
2494                 if (no_merged) {
2495                         return error(_("option `%s' is incompatible with --merged"),
2496                                      opt->long_name);
2497                 } else {
2498                         return error(_("option `%s' is incompatible with --no-merged"),
2499                                      opt->long_name);
2500                 }
2501         }
2502
2503         rf->merge = no_merged
2504                 ? REF_FILTER_MERGED_OMIT
2505                 : REF_FILTER_MERGED_INCLUDE;
2506
2507         if (get_oid(arg, &oid))
2508                 die(_("malformed object name %s"), arg);
2509
2510         rf->merge_commit = lookup_commit_reference_gently(the_repository,
2511                                                           &oid, 0);
2512         if (!rf->merge_commit)
2513                 return error(_("option `%s' must point to a commit"), opt->long_name);
2514
2515         return 0;
2516 }