git.oblomov.eu Git - git/blob - 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 "strvec.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 ref_trailer_buf {
  71         struct string_list filter_list;
  72         struct strbuf sepbuf;
  73         struct strbuf kvsepbuf;
  74 } ref_trailer_buf = {STRING_LIST_INIT_NODUP, STRBUF_INIT, STRBUF_INIT};
  75
  76 static struct expand_data {
  77         struct object_id oid;
  78         enum object_type type;
  79         unsigned long size;
  80         off_t disk_size;
  81         struct object_id delta_base_oid;
  82         void *content;
  83
  84         struct object_info info;
  85 } oi, oi_deref;
  86
  87 struct ref_to_worktree_entry {
  88         struct hashmap_entry ent;
  89         struct worktree *wt; /* key is wt->head_ref */
  90 };
  91
  92 static int ref_to_worktree_map_cmpfnc(const void *unused_lookupdata,
  93                                       const struct hashmap_entry *eptr,
  94                                       const struct hashmap_entry *kptr,
  95                                       const void *keydata_aka_refname)
  96 {
  97         const struct ref_to_worktree_entry *e, *k;
  98
  99         e = container_of(eptr, const struct ref_to_worktree_entry, ent);
 100         k = container_of(kptr, const struct ref_to_worktree_entry, ent);
 101
 102         return strcmp(e->wt->head_ref,
 103                 keydata_aka_refname ? keydata_aka_refname : k->wt->head_ref);
 104 }
 105
 106 static struct ref_to_worktree_map {
 107         struct hashmap map;
 108         struct worktree **worktrees;
 109 } ref_to_worktree_map;
 110
 111 /*
 112  * An atom is a valid field atom listed below, possibly prefixed with
 113  * a "*" to denote deref_tag().
 114  *
 115  * We parse given format string and sort specifiers, and make a list
 116  * of properties that we need to extract out of objects.  ref_array_item
 117  * structure will hold an array of values extracted that can be
 118  * indexed with the "atom number", which is an index into this
 119  * array.
 120  */
 121 static struct used_atom {
 122         const char *name;
 123         cmp_type type;
 124         info_source source;
 125         union {
 126                 char color[COLOR_MAXLEN];
 127                 struct align align;
 128                 struct {
 129                         enum {
 130                                 RR_REF, RR_TRACK, RR_TRACKSHORT, RR_REMOTE_NAME, RR_REMOTE_REF
 131                         } option;
 132                         struct refname_atom refname;
 133                         unsigned int nobracket : 1, push : 1, push_remote : 1;
 134                 } remote_ref;
 135                 struct {
 136                         enum { C_BARE, C_BODY, C_BODY_DEP, C_LENGTH, C_LINES,
 137                                C_SIG, C_SUB, C_SUB_SANITIZE, C_TRAILERS } option;
 138                         struct process_trailer_options trailer_opts;
 139                         unsigned int nlines;
 140                 } contents;
 141                 struct {
 142                         cmp_status cmp_status;
 143                         const char *str;
 144                 } if_then_else;
 145                 struct {
 146                         enum { O_FULL, O_LENGTH, O_SHORT } option;
 147                         unsigned int length;
 148                 } oid;
 149                 struct email_option {
 150                         enum { EO_RAW, EO_TRIM, EO_LOCALPART } option;
 151                 } email_option;
 152                 struct refname_atom refname;
 153                 char *head;
 154         } u;
 155 } *used_atom;
 156 static int used_atom_cnt, need_tagged, need_symref;
 157
 158 /*
 159  * Expand string, append it to strbuf *sb, then return error code ret.
 160  * Allow to save few lines of code.
 161  */
 162 static int strbuf_addf_ret(struct strbuf *sb, int ret, const char *fmt, ...)
 163 {
 164         va_list ap;
 165         va_start(ap, fmt);
 166         strbuf_vaddf(sb, fmt, ap);
 167         va_end(ap);
 168         return ret;
 169 }
 170
 171 static int color_atom_parser(const struct ref_format *format, struct used_atom *atom,
 172                              const char *color_value, struct strbuf *err)
 173 {
 174         if (!color_value)
 175                 return strbuf_addf_ret(err, -1, _("expected format: %%(color:<color>)"));
 176         if (color_parse(color_value, atom->u.color) < 0)
 177                 return strbuf_addf_ret(err, -1, _("unrecognized color: %%(color:%s)"),
 178                                        color_value);
 179         /*
 180          * We check this after we've parsed the color, which lets us complain
 181          * about syntactically bogus color names even if they won't be used.
 182          */
 183         if (!want_color(format->use_color))
 184                 color_parse("", atom->u.color);
 185         return 0;
 186 }
 187
 188 static int refname_atom_parser_internal(struct refname_atom *atom, const char *arg,
 189                                          const char *name, struct strbuf *err)
 190 {
 191         if (!arg)
 192                 atom->option = R_NORMAL;
 193         else if (!strcmp(arg, "short"))
 194                 atom->option = R_SHORT;
 195         else if (skip_prefix(arg, "lstrip=", &arg) ||
 196                  skip_prefix(arg, "strip=", &arg)) {
 197                 atom->option = R_LSTRIP;
 198                 if (strtol_i(arg, 10, &atom->lstrip))
 199                         return strbuf_addf_ret(err, -1, _("Integer value expected refname:lstrip=%s"), arg);
 200         } else if (skip_prefix(arg, "rstrip=", &arg)) {
 201                 atom->option = R_RSTRIP;
 202                 if (strtol_i(arg, 10, &atom->rstrip))
 203                         return strbuf_addf_ret(err, -1, _("Integer value expected refname:rstrip=%s"), arg);
 204         } else
 205                 return strbuf_addf_ret(err, -1, _("unrecognized %%(%s) argument: %s"), name, arg);
 206         return 0;
 207 }
 208
 209 static int remote_ref_atom_parser(const struct ref_format *format, struct used_atom *atom,
 210                                   const char *arg, struct strbuf *err)
 211 {
 212         struct string_list params = STRING_LIST_INIT_DUP;
 213         int i;
 214
 215         if (!strcmp(atom->name, "push") || starts_with(atom->name, "push:"))
 216                 atom->u.remote_ref.push = 1;
 217
 218         if (!arg) {
 219                 atom->u.remote_ref.option = RR_REF;
 220                 return refname_atom_parser_internal(&atom->u.remote_ref.refname,
 221                                                     arg, atom->name, err);
 222         }
 223
 224         atom->u.remote_ref.nobracket = 0;
 225         string_list_split(&params, arg, ',', -1);
 226
 227         for (i = 0; i < params.nr; i++) {
 228                 const char *s = params.items[i].string;
 229
 230                 if (!strcmp(s, "track"))
 231                         atom->u.remote_ref.option = RR_TRACK;
 232                 else if (!strcmp(s, "trackshort"))
 233                         atom->u.remote_ref.option = RR_TRACKSHORT;
 234                 else if (!strcmp(s, "nobracket"))
 235                         atom->u.remote_ref.nobracket = 1;
 236                 else if (!strcmp(s, "remotename")) {
 237                         atom->u.remote_ref.option = RR_REMOTE_NAME;
 238                         atom->u.remote_ref.push_remote = 1;
 239                 } else if (!strcmp(s, "remoteref")) {
 240                         atom->u.remote_ref.option = RR_REMOTE_REF;
 241                         atom->u.remote_ref.push_remote = 1;
 242                 } else {
 243                         atom->u.remote_ref.option = RR_REF;
 244                         if (refname_atom_parser_internal(&atom->u.remote_ref.refname,
 245                                                          arg, atom->name, err)) {
 246                                 string_list_clear(&params, 0);
 247                                 return -1;
 248                         }
 249                 }
 250         }
 251
 252         string_list_clear(&params, 0);
 253         return 0;
 254 }
 255
 256 static int objecttype_atom_parser(const struct ref_format *format, struct used_atom *atom,
 257                                   const char *arg, struct strbuf *err)
 258 {
 259         if (arg)
 260                 return strbuf_addf_ret(err, -1, _("%%(objecttype) does not take arguments"));
 261         if (*atom->name == '*')
 262                 oi_deref.info.typep = &oi_deref.type;
 263         else
 264                 oi.info.typep = &oi.type;
 265         return 0;
 266 }
 267
 268 static int objectsize_atom_parser(const struct ref_format *format, struct used_atom *atom,
 269                                   const char *arg, struct strbuf *err)
 270 {
 271         if (!arg) {
 272                 if (*atom->name == '*')
 273                         oi_deref.info.sizep = &oi_deref.size;
 274                 else
 275                         oi.info.sizep = &oi.size;
 276         } else if (!strcmp(arg, "disk")) {
 277                 if (*atom->name == '*')
 278                         oi_deref.info.disk_sizep = &oi_deref.disk_size;
 279                 else
 280                         oi.info.disk_sizep = &oi.disk_size;
 281         } else
 282                 return strbuf_addf_ret(err, -1, _("unrecognized %%(objectsize) argument: %s"), arg);
 283         return 0;
 284 }
 285
 286 static int deltabase_atom_parser(const struct ref_format *format, struct used_atom *atom,
 287                                  const char *arg, struct strbuf *err)
 288 {
 289         if (arg)
 290                 return strbuf_addf_ret(err, -1, _("%%(deltabase) does not take arguments"));
 291         if (*atom->name == '*')
 292                 oi_deref.info.delta_base_oid = &oi_deref.delta_base_oid;
 293         else
 294                 oi.info.delta_base_oid = &oi.delta_base_oid;
 295         return 0;
 296 }
 297
 298 static int body_atom_parser(const struct ref_format *format, struct used_atom *atom,
 299                             const char *arg, struct strbuf *err)
 300 {
 301         if (arg)
 302                 return strbuf_addf_ret(err, -1, _("%%(body) does not take arguments"));
 303         atom->u.contents.option = C_BODY_DEP;
 304         return 0;
 305 }
 306
 307 static int subject_atom_parser(const struct ref_format *format, struct used_atom *atom,
 308                                const char *arg, struct strbuf *err)
 309 {
 310         if (!arg)
 311                 atom->u.contents.option = C_SUB;
 312         else if (!strcmp(arg, "sanitize"))
 313                 atom->u.contents.option = C_SUB_SANITIZE;
 314         else
 315                 return strbuf_addf_ret(err, -1, _("unrecognized %%(subject) argument: %s"), arg);
 316         return 0;
 317 }
 318
 319 static int trailers_atom_parser(const struct ref_format *format, struct used_atom *atom,
 320                                 const char *arg, struct strbuf *err)
 321 {
 322         atom->u.contents.trailer_opts.no_divider = 1;
 323
 324         if (arg) {
 325                 const char *argbuf = xstrfmt("%s)", arg);
 326                 char *invalid_arg = NULL;
 327
 328                 if (format_set_trailers_options(&atom->u.contents.trailer_opts,
 329                     &ref_trailer_buf.filter_list,
 330                     &ref_trailer_buf.sepbuf,
 331                     &ref_trailer_buf.kvsepbuf,
 332                     &argbuf, &invalid_arg)) {
 333                         if (!invalid_arg)
 334                                 strbuf_addf(err, _("expected %%(trailers:key=<value>)"));
 335                         else
 336                                 strbuf_addf(err, _("unknown %%(trailers) argument: %s"), invalid_arg);
 337                         free((char *)invalid_arg);
 338                         return -1;
 339                 }
 340         }
 341         atom->u.contents.option = C_TRAILERS;
 342         return 0;
 343 }
 344
 345 static int contents_atom_parser(const struct ref_format *format, struct used_atom *atom,
 346                                 const char *arg, struct strbuf *err)
 347 {
 348         if (!arg)
 349                 atom->u.contents.option = C_BARE;
 350         else if (!strcmp(arg, "body"))
 351                 atom->u.contents.option = C_BODY;
 352         else if (!strcmp(arg, "size"))
 353                 atom->u.contents.option = C_LENGTH;
 354         else if (!strcmp(arg, "signature"))
 355                 atom->u.contents.option = C_SIG;
 356         else if (!strcmp(arg, "subject"))
 357                 atom->u.contents.option = C_SUB;
 358         else if (!strcmp(arg, "trailers")) {
 359                 if (trailers_atom_parser(format, atom, NULL, err))
 360                         return -1;
 361         } else if (skip_prefix(arg, "trailers:", &arg)) {
 362                 if (trailers_atom_parser(format, atom, arg, err))
 363                         return -1;
 364         } else if (skip_prefix(arg, "lines=", &arg)) {
 365                 atom->u.contents.option = C_LINES;
 366                 if (strtoul_ui(arg, 10, &atom->u.contents.nlines))
 367                         return strbuf_addf_ret(err, -1, _("positive value expected contents:lines=%s"), arg);
 368         } else
 369                 return strbuf_addf_ret(err, -1, _("unrecognized %%(contents) argument: %s"), arg);
 370         return 0;
 371 }
 372
 373 static int oid_atom_parser(const struct ref_format *format, struct used_atom *atom,
 374                            const char *arg, struct strbuf *err)
 375 {
 376         if (!arg)
 377                 atom->u.oid.option = O_FULL;
 378         else if (!strcmp(arg, "short"))
 379                 atom->u.oid.option = O_SHORT;
 380         else if (skip_prefix(arg, "short=", &arg)) {
 381                 atom->u.oid.option = O_LENGTH;
 382                 if (strtoul_ui(arg, 10, &atom->u.oid.length) ||
 383                     atom->u.oid.length == 0)
 384                         return strbuf_addf_ret(err, -1, _("positive value expected '%s' in %%(%s)"), arg, atom->name);
 385                 if (atom->u.oid.length < MINIMUM_ABBREV)
 386                         atom->u.oid.length = MINIMUM_ABBREV;
 387         } else
 388                 return strbuf_addf_ret(err, -1, _("unrecognized argument '%s' in %%(%s)"), arg, atom->name);
 389         return 0;
 390 }
 391
 392 static int person_email_atom_parser(const struct ref_format *format, struct used_atom *atom,
 393                                     const char *arg, struct strbuf *err)
 394 {
 395         if (!arg)
 396                 atom->u.email_option.option = EO_RAW;
 397         else if (!strcmp(arg, "trim"))
 398                 atom->u.email_option.option = EO_TRIM;
 399         else if (!strcmp(arg, "localpart"))
 400                 atom->u.email_option.option = EO_LOCALPART;
 401         else
 402                 return strbuf_addf_ret(err, -1, _("unrecognized email option: %s"), arg);
 403         return 0;
 404 }
 405
 406 static int refname_atom_parser(const struct ref_format *format, struct used_atom *atom,
 407                                const char *arg, struct strbuf *err)
 408 {
 409         return refname_atom_parser_internal(&atom->u.refname, arg, atom->name, err);
 410 }
 411
 412 static align_type parse_align_position(const char *s)
 413 {
 414         if (!strcmp(s, "right"))
 415                 return ALIGN_RIGHT;
 416         else if (!strcmp(s, "middle"))
 417                 return ALIGN_MIDDLE;
 418         else if (!strcmp(s, "left"))
 419                 return ALIGN_LEFT;
 420         return -1;
 421 }
 422
 423 static int align_atom_parser(const struct ref_format *format, struct used_atom *atom,
 424                              const char *arg, struct strbuf *err)
 425 {
 426         struct align *align = &atom->u.align;
 427         struct string_list params = STRING_LIST_INIT_DUP;
 428         int i;
 429         unsigned int width = ~0U;
 430
 431         if (!arg)
 432                 return strbuf_addf_ret(err, -1, _("expected format: %%(align:<width>,<position>)"));
 433
 434         align->position = ALIGN_LEFT;
 435
 436         string_list_split(&params, arg, ',', -1);
 437         for (i = 0; i < params.nr; i++) {
 438                 const char *s = params.items[i].string;
 439                 int position;
 440
 441                 if (skip_prefix(s, "position=", &s)) {
 442                         position = parse_align_position(s);
 443                         if (position < 0) {
 444                                 strbuf_addf(err, _("unrecognized position:%s"), s);
 445                                 string_list_clear(&params, 0);
 446                                 return -1;
 447                         }
 448                         align->position = position;
 449                 } else if (skip_prefix(s, "width=", &s)) {
 450                         if (strtoul_ui(s, 10, &width)) {
 451                                 strbuf_addf(err, _("unrecognized width:%s"), s);
 452                                 string_list_clear(&params, 0);
 453                                 return -1;
 454                         }
 455                 } else if (!strtoul_ui(s, 10, &width))
 456                         ;
 457                 else if ((position = parse_align_position(s)) >= 0)
 458                         align->position = position;
 459                 else {
 460                         strbuf_addf(err, _("unrecognized %%(align) argument: %s"), s);
 461                         string_list_clear(&params, 0);
 462                         return -1;
 463                 }
 464         }
 465
 466         if (width == ~0U) {
 467                 string_list_clear(&params, 0);
 468                 return strbuf_addf_ret(err, -1, _("positive width expected with the %%(align) atom"));
 469         }
 470         align->width = width;
 471         string_list_clear(&params, 0);
 472         return 0;
 473 }
 474
 475 static int if_atom_parser(const struct ref_format *format, struct used_atom *atom,
 476                           const char *arg, struct strbuf *err)
 477 {
 478         if (!arg) {
 479                 atom->u.if_then_else.cmp_status = COMPARE_NONE;
 480                 return 0;
 481         } else if (skip_prefix(arg, "equals=", &atom->u.if_then_else.str)) {
 482                 atom->u.if_then_else.cmp_status = COMPARE_EQUAL;
 483         } else if (skip_prefix(arg, "notequals=", &atom->u.if_then_else.str)) {
 484                 atom->u.if_then_else.cmp_status = COMPARE_UNEQUAL;
 485         } else
 486                 return strbuf_addf_ret(err, -1, _("unrecognized %%(if) argument: %s"), arg);
 487         return 0;
 488 }
 489
 490 static int head_atom_parser(const struct ref_format *format, struct used_atom *atom,
 491                             const char *arg, struct strbuf *unused_err)
 492 {
 493         atom->u.head = resolve_refdup("HEAD", RESOLVE_REF_READING, NULL, NULL);
 494         return 0;
 495 }
 496
 497 static struct {
 498         const char *name;
 499         info_source source;
 500         cmp_type cmp_type;
 501         int (*parser)(const struct ref_format *format, struct used_atom *atom,
 502                       const char *arg, struct strbuf *err);
 503 } valid_atom[] = {
 504         { "refname", SOURCE_NONE, FIELD_STR, refname_atom_parser },
 505         { "objecttype", SOURCE_OTHER, FIELD_STR, objecttype_atom_parser },
 506         { "objectsize", SOURCE_OTHER, FIELD_ULONG, objectsize_atom_parser },
 507         { "objectname", SOURCE_OTHER, FIELD_STR, oid_atom_parser },
 508         { "deltabase", SOURCE_OTHER, FIELD_STR, deltabase_atom_parser },
 509         { "tree", SOURCE_OBJ, FIELD_STR, oid_atom_parser },
 510         { "parent", SOURCE_OBJ, FIELD_STR, oid_atom_parser },
 511         { "numparent", SOURCE_OBJ, FIELD_ULONG },
 512         { "object", SOURCE_OBJ },
 513         { "type", SOURCE_OBJ },
 514         { "tag", SOURCE_OBJ },
 515         { "author", SOURCE_OBJ },
 516         { "authorname", SOURCE_OBJ },
 517         { "authoremail", SOURCE_OBJ, FIELD_STR, person_email_atom_parser },
 518         { "authordate", SOURCE_OBJ, FIELD_TIME },
 519         { "committer", SOURCE_OBJ },
 520         { "committername", SOURCE_OBJ },
 521         { "committeremail", SOURCE_OBJ, FIELD_STR, person_email_atom_parser },
 522         { "committerdate", SOURCE_OBJ, FIELD_TIME },
 523         { "tagger", SOURCE_OBJ },
 524         { "taggername", SOURCE_OBJ },
 525         { "taggeremail", SOURCE_OBJ, FIELD_STR, person_email_atom_parser },
 526         { "taggerdate", SOURCE_OBJ, FIELD_TIME },
 527         { "creator", SOURCE_OBJ },
 528         { "creatordate", SOURCE_OBJ, FIELD_TIME },
 529         { "subject", SOURCE_OBJ, FIELD_STR, subject_atom_parser },
 530         { "body", SOURCE_OBJ, FIELD_STR, body_atom_parser },
 531         { "trailers", SOURCE_OBJ, FIELD_STR, trailers_atom_parser },
 532         { "contents", SOURCE_OBJ, FIELD_STR, contents_atom_parser },
 533         { "upstream", SOURCE_NONE, FIELD_STR, remote_ref_atom_parser },
 534         { "push", SOURCE_NONE, FIELD_STR, remote_ref_atom_parser },
 535         { "symref", SOURCE_NONE, FIELD_STR, refname_atom_parser },
 536         { "flag", SOURCE_NONE },
 537         { "HEAD", SOURCE_NONE, FIELD_STR, head_atom_parser },
 538         { "color", SOURCE_NONE, FIELD_STR, color_atom_parser },
 539         { "worktreepath", SOURCE_NONE },
 540         { "align", SOURCE_NONE, FIELD_STR, align_atom_parser },
 541         { "end", SOURCE_NONE },
 542         { "if", SOURCE_NONE, FIELD_STR, if_atom_parser },
 543         { "then", SOURCE_NONE },
 544         { "else", SOURCE_NONE },
 545         /*
 546          * Please update $__git_ref_fieldlist in git-completion.bash
 547          * when you add new atoms
 548          */
 549 };
 550
 551 #define REF_FORMATTING_STATE_INIT  { 0, NULL }
 552
 553 struct ref_formatting_stack {
 554         struct ref_formatting_stack *prev;
 555         struct strbuf output;
 556         void (*at_end)(struct ref_formatting_stack **stack);
 557         void *at_end_data;
 558 };
 559
 560 struct ref_formatting_state {
 561         int quote_style;
 562         struct ref_formatting_stack *stack;
 563 };
 564
 565 struct atom_value {
 566         const char *s;
 567         int (*handler)(struct atom_value *atomv, struct ref_formatting_state *state,
 568                        struct strbuf *err);
 569         uintmax_t value; /* used for sorting when not FIELD_STR */
 570         struct used_atom *atom;
 571 };
 572
 573 /*
 574  * Used to parse format string and sort specifiers
 575  */
 576 static int parse_ref_filter_atom(const struct ref_format *format,
 577                                  const char *atom, const char *ep,
 578                                  struct strbuf *err)
 579 {
 580         const char *sp;
 581         const char *arg;
 582         int i, at, atom_len;
 583
 584         sp = atom;
 585         if (*sp == '*' && sp < ep)
 586                 sp++; /* deref */
 587         if (ep <= sp)
 588                 return strbuf_addf_ret(err, -1, _("malformed field name: %.*s"),
 589                                        (int)(ep-atom), atom);
 590
 591         /* Do we have the atom already used elsewhere? */
 592         for (i = 0; i < used_atom_cnt; i++) {
 593                 int len = strlen(used_atom[i].name);
 594                 if (len == ep - atom && !memcmp(used_atom[i].name, atom, len))
 595                         return i;
 596         }
 597
 598         /*
 599          * If the atom name has a colon, strip it and everything after
 600          * it off - it specifies the format for this entry, and
 601          * shouldn't be used for checking against the valid_atom
 602          * table.
 603          */
 604         arg = memchr(sp, ':', ep - sp);
 605         atom_len = (arg ? arg : ep) - sp;
 606
 607         /* Is the atom a valid one? */
 608         for (i = 0; i < ARRAY_SIZE(valid_atom); i++) {
 609                 int len = strlen(valid_atom[i].name);
 610                 if (len == atom_len && !memcmp(valid_atom[i].name, sp, len))
 611                         break;
 612         }
 613
 614         if (ARRAY_SIZE(valid_atom) <= i)
 615                 return strbuf_addf_ret(err, -1, _("unknown field name: %.*s"),
 616                                        (int)(ep-atom), atom);
 617         if (valid_atom[i].source != SOURCE_NONE && !have_git_dir())
 618                 return strbuf_addf_ret(err, -1,
 619                                        _("not a git repository, but the field '%.*s' requires access to object data"),
 620                                        (int)(ep-atom), atom);
 621
 622         /* Add it in, including the deref prefix */
 623         at = used_atom_cnt;
 624         used_atom_cnt++;
 625         REALLOC_ARRAY(used_atom, used_atom_cnt);
 626         used_atom[at].name = xmemdupz(atom, ep - atom);
 627         used_atom[at].type = valid_atom[i].cmp_type;
 628         used_atom[at].source = valid_atom[i].source;
 629         if (used_atom[at].source == SOURCE_OBJ) {
 630                 if (*atom == '*')
 631                         oi_deref.info.contentp = &oi_deref.content;
 632                 else
 633                         oi.info.contentp = &oi.content;
 634         }
 635         if (arg) {
 636                 arg = used_atom[at].name + (arg - atom) + 1;
 637                 if (!*arg) {
 638                         /*
 639                          * Treat empty sub-arguments list as NULL (i.e.,
 640                          * "%(atom:)" is equivalent to "%(atom)").
 641                          */
 642                         arg = NULL;
 643                 }
 644         }
 645         memset(&used_atom[at].u, 0, sizeof(used_atom[at].u));
 646         if (valid_atom[i].parser && valid_atom[i].parser(format, &used_atom[at], arg, err))
 647                 return -1;
 648         if (*atom == '*')
 649                 need_tagged = 1;
 650         if (!strcmp(valid_atom[i].name, "symref"))
 651                 need_symref = 1;
 652         return at;
 653 }
 654
 655 static void quote_formatting(struct strbuf *s, const char *str, int quote_style)
 656 {
 657         switch (quote_style) {
 658         case QUOTE_NONE:
 659                 strbuf_addstr(s, str);
 660                 break;
 661         case QUOTE_SHELL:
 662                 sq_quote_buf(s, str);
 663                 break;
 664         case QUOTE_PERL:
 665                 perl_quote_buf(s, str);
 666                 break;
 667         case QUOTE_PYTHON:
 668                 python_quote_buf(s, str);
 669                 break;
 670         case QUOTE_TCL:
 671                 tcl_quote_buf(s, str);
 672                 break;
 673         }
 674 }
 675
 676 static int append_atom(struct atom_value *v, struct ref_formatting_state *state,
 677                        struct strbuf *unused_err)
 678 {
 679         /*
 680          * Quote formatting is only done when the stack has a single
 681          * element. Otherwise quote formatting is done on the
 682          * element's entire output strbuf when the %(end) atom is
 683          * encountered.
 684          */
 685         if (!state->stack->prev)
 686                 quote_formatting(&state->stack->output, v->s, state->quote_style);
 687         else
 688                 strbuf_addstr(&state->stack->output, v->s);
 689         return 0;
 690 }
 691
 692 static void push_stack_element(struct ref_formatting_stack **stack)
 693 {
 694         struct ref_formatting_stack *s = xcalloc(1, sizeof(struct ref_formatting_stack));
 695
 696         strbuf_init(&s->output, 0);
 697         s->prev = *stack;
 698         *stack = s;
 699 }
 700
 701 static void pop_stack_element(struct ref_formatting_stack **stack)
 702 {
 703         struct ref_formatting_stack *current = *stack;
 704         struct ref_formatting_stack *prev = current->prev;
 705
 706         if (prev)
 707                 strbuf_addbuf(&prev->output, &current->output);
 708         strbuf_release(&current->output);
 709         free(current);
 710         *stack = prev;
 711 }
 712
 713 static void end_align_handler(struct ref_formatting_stack **stack)
 714 {
 715         struct ref_formatting_stack *cur = *stack;
 716         struct align *align = (struct align *)cur->at_end_data;
 717         struct strbuf s = STRBUF_INIT;
 718
 719         strbuf_utf8_align(&s, align->position, align->width, cur->output.buf);
 720         strbuf_swap(&cur->output, &s);
 721         strbuf_release(&s);
 722 }
 723
 724 static int align_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state,
 725                               struct strbuf *unused_err)
 726 {
 727         struct ref_formatting_stack *new_stack;
 728
 729         push_stack_element(&state->stack);
 730         new_stack = state->stack;
 731         new_stack->at_end = end_align_handler;
 732         new_stack->at_end_data = &atomv->atom->u.align;
 733         return 0;
 734 }
 735
 736 static void if_then_else_handler(struct ref_formatting_stack **stack)
 737 {
 738         struct ref_formatting_stack *cur = *stack;
 739         struct ref_formatting_stack *prev = cur->prev;
 740         struct if_then_else *if_then_else = (struct if_then_else *)cur->at_end_data;
 741
 742         if (!if_then_else->then_atom_seen)
 743                 die(_("format: %%(if) atom used without a %%(then) atom"));
 744
 745         if (if_then_else->else_atom_seen) {
 746                 /*
 747                  * There is an %(else) atom: we need to drop one state from the
 748                  * stack, either the %(else) branch if the condition is satisfied, or
 749                  * the %(then) branch if it isn't.
 750                  */
 751                 if (if_then_else->condition_satisfied) {
 752                         strbuf_reset(&cur->output);
 753                         pop_stack_element(&cur);
 754                 } else {
 755                         strbuf_swap(&cur->output, &prev->output);
 756                         strbuf_reset(&cur->output);
 757                         pop_stack_element(&cur);
 758                 }
 759         } else if (!if_then_else->condition_satisfied) {
 760                 /*
 761                  * No %(else) atom: just drop the %(then) branch if the
 762                  * condition is not satisfied.
 763                  */
 764                 strbuf_reset(&cur->output);
 765         }
 766
 767         *stack = cur;
 768         free(if_then_else);
 769 }
 770
 771 static int if_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state,
 772                            struct strbuf *unused_err)
 773 {
 774         struct ref_formatting_stack *new_stack;
 775         struct if_then_else *if_then_else = xcalloc(1,
 776                                                     sizeof(struct if_then_else));
 777
 778         if_then_else->str = atomv->atom->u.if_then_else.str;
 779         if_then_else->cmp_status = atomv->atom->u.if_then_else.cmp_status;
 780
 781         push_stack_element(&state->stack);
 782         new_stack = state->stack;
 783         new_stack->at_end = if_then_else_handler;
 784         new_stack->at_end_data = if_then_else;
 785         return 0;
 786 }
 787
 788 static int is_empty(const char *s)
 789 {
 790         while (*s != '\0') {
 791                 if (!isspace(*s))
 792                         return 0;
 793                 s++;
 794         }
 795         return 1;
 796 }
 797
 798 static int then_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state,
 799                              struct strbuf *err)
 800 {
 801         struct ref_formatting_stack *cur = state->stack;
 802         struct if_then_else *if_then_else = NULL;
 803
 804         if (cur->at_end == if_then_else_handler)
 805                 if_then_else = (struct if_then_else *)cur->at_end_data;
 806         if (!if_then_else)
 807                 return strbuf_addf_ret(err, -1, _("format: %%(then) atom used without an %%(if) atom"));
 808         if (if_then_else->then_atom_seen)
 809                 return strbuf_addf_ret(err, -1, _("format: %%(then) atom used more than once"));
 810         if (if_then_else->else_atom_seen)
 811                 return strbuf_addf_ret(err, -1, _("format: %%(then) atom used after %%(else)"));
 812         if_then_else->then_atom_seen = 1;
 813         /*
 814          * If the 'equals' or 'notequals' attribute is used then
 815          * perform the required comparison. If not, only non-empty
 816          * strings satisfy the 'if' condition.
 817          */
 818         if (if_then_else->cmp_status == COMPARE_EQUAL) {
 819                 if (!strcmp(if_then_else->str, cur->output.buf))
 820                         if_then_else->condition_satisfied = 1;
 821         } else if (if_then_else->cmp_status == COMPARE_UNEQUAL) {
 822                 if (strcmp(if_then_else->str, cur->output.buf))
 823                         if_then_else->condition_satisfied = 1;
 824         } else if (cur->output.len && !is_empty(cur->output.buf))
 825                 if_then_else->condition_satisfied = 1;
 826         strbuf_reset(&cur->output);
 827         return 0;
 828 }
 829
 830 static int else_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state,
 831                              struct strbuf *err)
 832 {
 833         struct ref_formatting_stack *prev = state->stack;
 834         struct if_then_else *if_then_else = NULL;
 835
 836         if (prev->at_end == if_then_else_handler)
 837                 if_then_else = (struct if_then_else *)prev->at_end_data;
 838         if (!if_then_else)
 839                 return strbuf_addf_ret(err, -1, _("format: %%(else) atom used without an %%(if) atom"));
 840         if (!if_then_else->then_atom_seen)
 841                 return strbuf_addf_ret(err, -1, _("format: %%(else) atom used without a %%(then) atom"));
 842         if (if_then_else->else_atom_seen)
 843                 return strbuf_addf_ret(err, -1, _("format: %%(else) atom used more than once"));
 844         if_then_else->else_atom_seen = 1;
 845         push_stack_element(&state->stack);
 846         state->stack->at_end_data = prev->at_end_data;
 847         state->stack->at_end = prev->at_end;
 848         return 0;
 849 }
 850
 851 static int end_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state,
 852                             struct strbuf *err)
 853 {
 854         struct ref_formatting_stack *current = state->stack;
 855         struct strbuf s = STRBUF_INIT;
 856
 857         if (!current->at_end)
 858                 return strbuf_addf_ret(err, -1, _("format: %%(end) atom used without corresponding atom"));
 859         current->at_end(&state->stack);
 860
 861         /*  Stack may have been popped within at_end(), hence reset the current pointer */
 862         current = state->stack;
 863
 864         /*
 865          * Perform quote formatting when the stack element is that of
 866          * a supporting atom. If nested then perform quote formatting
 867          * only on the topmost supporting atom.
 868          */
 869         if (!current->prev->prev) {
 870                 quote_formatting(&s, current->output.buf, state->quote_style);
 871                 strbuf_swap(&current->output, &s);
 872         }
 873         strbuf_release(&s);
 874         pop_stack_element(&state->stack);
 875         return 0;
 876 }
 877
 878 /*
 879  * In a format string, find the next occurrence of %(atom).
 880  */
 881 static const char *find_next(const char *cp)
 882 {
 883         while (*cp) {
 884                 if (*cp == '%') {
 885                         /*
 886                          * %( is the start of an atom;
 887                          * %% is a quoted per-cent.
 888                          */
 889                         if (cp[1] == '(')
 890                                 return cp;
 891                         else if (cp[1] == '%')
 892                                 cp++; /* skip over two % */
 893                         /* otherwise this is a singleton, literal % */
 894                 }
 895                 cp++;
 896         }
 897         return NULL;
 898 }
 899
 900 /*
 901  * Make sure the format string is well formed, and parse out
 902  * the used atoms.
 903  */
 904 int verify_ref_format(struct ref_format *format)
 905 {
 906         const char *cp, *sp;
 907
 908         format->need_color_reset_at_eol = 0;
 909         for (cp = format->format; *cp && (sp = find_next(cp)); ) {
 910                 struct strbuf err = STRBUF_INIT;
 911                 const char *color, *ep = strchr(sp, ')');
 912                 int at;
 913
 914                 if (!ep)
 915                         return error(_("malformed format string %s"), sp);
 916                 /* sp points at "%(" and ep points at the closing ")" */
 917                 at = parse_ref_filter_atom(format, sp + 2, ep, &err);
 918                 if (at < 0)
 919                         die("%s", err.buf);
 920                 cp = ep + 1;
 921
 922                 if (skip_prefix(used_atom[at].name, "color:", &color))
 923                         format->need_color_reset_at_eol = !!strcmp(color, "reset");
 924                 strbuf_release(&err);
 925         }
 926         if (format->need_color_reset_at_eol && !want_color(format->use_color))
 927                 format->need_color_reset_at_eol = 0;
 928         return 0;
 929 }
 930
 931 static const char *do_grab_oid(const char *field, const struct object_id *oid,
 932                                struct used_atom *atom)
 933 {
 934         switch (atom->u.oid.option) {
 935         case O_FULL:
 936                 return oid_to_hex(oid);
 937         case O_LENGTH:
 938                 return find_unique_abbrev(oid, atom->u.oid.length);
 939         case O_SHORT:
 940                 return find_unique_abbrev(oid, DEFAULT_ABBREV);
 941         default:
 942                 BUG("unknown %%(%s) option", field);
 943         }
 944 }
 945
 946 static int grab_oid(const char *name, const char *field, const struct object_id *oid,
 947                     struct atom_value *v, struct used_atom *atom)
 948 {
 949         if (starts_with(name, field)) {
 950                 v->s = xstrdup(do_grab_oid(field, oid, atom));
 951                 return 1;
 952         }
 953         return 0;
 954 }
 955
 956 /* See grab_values */
 957 static void grab_common_values(struct atom_value *val, int deref, struct expand_data *oi)
 958 {
 959         int i;
 960
 961         for (i = 0; i < used_atom_cnt; i++) {
 962                 const char *name = used_atom[i].name;
 963                 struct atom_value *v = &val[i];
 964                 if (!!deref != (*name == '*'))
 965                         continue;
 966                 if (deref)
 967                         name++;
 968                 if (!strcmp(name, "objecttype"))
 969                         v->s = xstrdup(type_name(oi->type));
 970                 else if (!strcmp(name, "objectsize:disk")) {
 971                         v->value = oi->disk_size;
 972                         v->s = xstrfmt("%"PRIuMAX, (uintmax_t)oi->disk_size);
 973                 } else if (!strcmp(name, "objectsize")) {
 974                         v->value = oi->size;
 975                         v->s = xstrfmt("%"PRIuMAX , (uintmax_t)oi->size);
 976                 } else if (!strcmp(name, "deltabase"))
 977                         v->s = xstrdup(oid_to_hex(&oi->delta_base_oid));
 978                 else if (deref)
 979                         grab_oid(name, "objectname", &oi->oid, v, &used_atom[i]);
 980         }
 981 }
 982
 983 /* See grab_values */
 984 static void grab_tag_values(struct atom_value *val, int deref, struct object *obj)
 985 {
 986         int i;
 987         struct tag *tag = (struct tag *) obj;
 988
 989         for (i = 0; i < used_atom_cnt; i++) {
 990                 const char *name = used_atom[i].name;
 991                 struct atom_value *v = &val[i];
 992                 if (!!deref != (*name == '*'))
 993                         continue;
 994                 if (deref)
 995                         name++;
 996                 if (!strcmp(name, "tag"))
 997                         v->s = xstrdup(tag->tag);
 998                 else if (!strcmp(name, "type") && tag->tagged)
 999                         v->s = xstrdup(type_name(tag->tagged->type));
1000                 else if (!strcmp(name, "object") && tag->tagged)
1001                         v->s = xstrdup(oid_to_hex(&tag->tagged->oid));
1002         }
1003 }
1004
1005 /* See grab_values */
1006 static void grab_commit_values(struct atom_value *val, int deref, struct object *obj)
1007 {
1008         int i;
1009         struct commit *commit = (struct commit *) obj;
1010
1011         for (i = 0; i < used_atom_cnt; i++) {
1012                 const char *name = used_atom[i].name;
1013                 struct atom_value *v = &val[i];
1014                 if (!!deref != (*name == '*'))
1015                         continue;
1016                 if (deref)
1017                         name++;
1018                 if (grab_oid(name, "tree", get_commit_tree_oid(commit), v, &used_atom[i]))
1019                         continue;
1020                 if (!strcmp(name, "numparent")) {
1021                         v->value = commit_list_count(commit->parents);
1022                         v->s = xstrfmt("%lu", (unsigned long)v->value);
1023                 }
1024                 else if (starts_with(name, "parent")) {
1025                         struct commit_list *parents;
1026                         struct strbuf s = STRBUF_INIT;
1027                         for (parents = commit->parents; parents; parents = parents->next) {
1028                                 struct object_id *oid = &parents->item->object.oid;
1029                                 if (parents != commit->parents)
1030                                         strbuf_addch(&s, ' ');
1031                                 strbuf_addstr(&s, do_grab_oid("parent", oid, &used_atom[i]));
1032                         }
1033                         v->s = strbuf_detach(&s, NULL);
1034                 }
1035         }
1036 }
1037
1038 static const char *find_wholine(const char *who, int wholen, const char *buf)
1039 {
1040         const char *eol;
1041         while (*buf) {
1042                 if (!strncmp(buf, who, wholen) &&
1043                     buf[wholen] == ' ')
1044                         return buf + wholen + 1;
1045                 eol = strchr(buf, '\n');
1046                 if (!eol)
1047                         return "";
1048                 eol++;
1049                 if (*eol == '\n')
1050                         return ""; /* end of header */
1051                 buf = eol;
1052         }
1053         return "";
1054 }
1055
1056 static const char *copy_line(const char *buf)
1057 {
1058         const char *eol = strchrnul(buf, '\n');
1059         return xmemdupz(buf, eol - buf);
1060 }
1061
1062 static const char *copy_name(const char *buf)
1063 {
1064         const char *cp;
1065         for (cp = buf; *cp && *cp != '\n'; cp++) {
1066                 if (!strncmp(cp, " <", 2))
1067                         return xmemdupz(buf, cp - buf);
1068         }
1069         return xstrdup("");
1070 }
1071
1072 static const char *copy_email(const char *buf, struct used_atom *atom)
1073 {
1074         const char *email = strchr(buf, '<');
1075         const char *eoemail;
1076         if (!email)
1077                 return xstrdup("");
1078         switch (atom->u.email_option.option) {
1079         case EO_RAW:
1080                 eoemail = strchr(email, '>');
1081                 if (eoemail)
1082                         eoemail++;
1083                 break;
1084         case EO_TRIM:
1085                 email++;
1086                 eoemail = strchr(email, '>');
1087                 break;
1088         case EO_LOCALPART:
1089                 email++;
1090                 eoemail = strchr(email, '@');
1091                 if (!eoemail)
1092                         eoemail = strchr(email, '>');
1093                 break;
1094         default:
1095                 BUG("unknown email option");
1096         }
1097
1098         if (!eoemail)
1099                 return xstrdup("");
1100         return xmemdupz(email, eoemail - email);
1101 }
1102
1103 static char *copy_subject(const char *buf, unsigned long len)
1104 {
1105         struct strbuf sb = STRBUF_INIT;
1106         int i;
1107
1108         for (i = 0; i < len; i++) {
1109                 if (buf[i] == '\r' && i + 1 < len && buf[i + 1] == '\n')
1110                         continue; /* ignore CR in CRLF */
1111
1112                 if (buf[i] == '\n')
1113                         strbuf_addch(&sb, ' ');
1114                 else
1115                         strbuf_addch(&sb, buf[i]);
1116         }
1117         return strbuf_detach(&sb, NULL);
1118 }
1119
1120 static void grab_date(const char *buf, struct atom_value *v, const char *atomname)
1121 {
1122         const char *eoemail = strstr(buf, "> ");
1123         char *zone;
1124         timestamp_t timestamp;
1125         long tz;
1126         struct date_mode date_mode = { DATE_NORMAL };
1127         const char *formatp;
1128
1129         /*
1130          * We got here because atomname ends in "date" or "date<something>";
1131          * it's not possible that <something> is not ":<format>" because
1132          * parse_ref_filter_atom() wouldn't have allowed it, so we can assume that no
1133          * ":" means no format is specified, and use the default.
1134          */
1135         formatp = strchr(atomname, ':');
1136         if (formatp != NULL) {
1137                 formatp++;
1138                 parse_date_format(formatp, &date_mode);
1139         }
1140
1141         if (!eoemail)
1142                 goto bad;
1143         timestamp = parse_timestamp(eoemail + 2, &zone, 10);
1144         if (timestamp == TIME_MAX)
1145                 goto bad;
1146         tz = strtol(zone, NULL, 10);
1147         if ((tz == LONG_MIN || tz == LONG_MAX) && errno == ERANGE)
1148                 goto bad;
1149         v->s = xstrdup(show_date(timestamp, tz, &date_mode));
1150         v->value = timestamp;
1151         return;
1152  bad:
1153         v->s = xstrdup("");
1154         v->value = 0;
1155 }
1156
1157 /* See grab_values */
1158 static void grab_person(const char *who, struct atom_value *val, int deref, void *buf)
1159 {
1160         int i;
1161         int wholen = strlen(who);
1162         const char *wholine = NULL;
1163
1164         for (i = 0; i < used_atom_cnt; i++) {
1165                 const char *name = used_atom[i].name;
1166                 struct atom_value *v = &val[i];
1167                 if (!!deref != (*name == '*'))
1168                         continue;
1169                 if (deref)
1170                         name++;
1171                 if (strncmp(who, name, wholen))
1172                         continue;
1173                 if (name[wholen] != 0 &&
1174                     strcmp(name + wholen, "name") &&
1175                     !starts_with(name + wholen, "email") &&
1176                     !starts_with(name + wholen, "date"))
1177                         continue;
1178                 if (!wholine)
1179                         wholine = find_wholine(who, wholen, buf);
1180                 if (!wholine)
1181                         return; /* no point looking for it */
1182                 if (name[wholen] == 0)
1183                         v->s = copy_line(wholine);
1184                 else if (!strcmp(name + wholen, "name"))
1185                         v->s = copy_name(wholine);
1186                 else if (starts_with(name + wholen, "email"))
1187                         v->s = copy_email(wholine, &used_atom[i]);
1188                 else if (starts_with(name + wholen, "date"))
1189                         grab_date(wholine, v, name);
1190         }
1191
1192         /*
1193          * For a tag or a commit object, if "creator" or "creatordate" is
1194          * requested, do something special.
1195          */
1196         if (strcmp(who, "tagger") && strcmp(who, "committer"))
1197                 return; /* "author" for commit object is not wanted */
1198         if (!wholine)
1199                 wholine = find_wholine(who, wholen, buf);
1200         if (!wholine)
1201                 return;
1202         for (i = 0; i < used_atom_cnt; i++) {
1203                 const char *name = used_atom[i].name;
1204                 struct atom_value *v = &val[i];
1205                 if (!!deref != (*name == '*'))
1206                         continue;
1207                 if (deref)
1208                         name++;
1209
1210                 if (starts_with(name, "creatordate"))
1211                         grab_date(wholine, v, name);
1212                 else if (!strcmp(name, "creator"))
1213                         v->s = copy_line(wholine);
1214         }
1215 }
1216
1217 static void find_subpos(const char *buf,
1218                         const char **sub, size_t *sublen,
1219                         const char **body, size_t *bodylen,
1220                         size_t *nonsiglen,
1221                         const char **sig, size_t *siglen)
1222 {
1223         struct strbuf payload = STRBUF_INIT;
1224         struct strbuf signature = STRBUF_INIT;
1225         const char *eol;
1226         const char *end = buf + strlen(buf);
1227         const char *sigstart;
1228
1229         /* parse signature first; we might not even have a subject line */
1230         parse_signature(buf, end - buf, &payload, &signature);
1231
1232         /* skip past header until we hit empty line */
1233         while (*buf && *buf != '\n') {
1234                 eol = strchrnul(buf, '\n');
1235                 if (*eol)
1236                         eol++;
1237                 buf = eol;
1238         }
1239         /* skip any empty lines */
1240         while (*buf == '\n')
1241                 buf++;
1242         *sig = strbuf_detach(&signature, siglen);
1243         sigstart = buf + parse_signed_buffer(buf, strlen(buf));
1244
1245         /* subject is first non-empty line */
1246         *sub = buf;
1247         /* subject goes to first empty line before signature begins */
1248         if ((eol = strstr(*sub, "\n\n"))) {
1249                 eol = eol < sigstart ? eol : sigstart;
1250         /* check if message uses CRLF */
1251         } else if (! (eol = strstr(*sub, "\r\n\r\n"))) {
1252                 /* treat whole message as subject */
1253                 eol = strrchr(*sub, '\0');
1254         }
1255         buf = eol;
1256         *sublen = buf - *sub;
1257         /* drop trailing newline, if present */
1258         while (*sublen && ((*sub)[*sublen - 1] == '\n' ||
1259                            (*sub)[*sublen - 1] == '\r'))
1260                 *sublen -= 1;
1261
1262         /* skip any empty lines */
1263         while (*buf == '\n' || *buf == '\r')
1264                 buf++;
1265         *body = buf;
1266         *bodylen = strlen(buf);
1267         *nonsiglen = sigstart - buf;
1268 }
1269
1270 /*
1271  * If 'lines' is greater than 0, append that many lines from the given
1272  * 'buf' of length 'size' to the given strbuf.
1273  */
1274 static void append_lines(struct strbuf *out, const char *buf, unsigned long size, int lines)
1275 {
1276         int i;
1277         const char *sp, *eol;
1278         size_t len;
1279
1280         sp = buf;
1281
1282         for (i = 0; i < lines && sp < buf + size; i++) {
1283                 if (i)
1284                         strbuf_addstr(out, "\n    ");
1285                 eol = memchr(sp, '\n', size - (sp - buf));
1286                 len = eol ? eol - sp : size - (sp - buf);
1287                 strbuf_add(out, sp, len);
1288                 if (!eol)
1289                         break;
1290                 sp = eol + 1;
1291         }
1292 }
1293
1294 /* See grab_values */
1295 static void grab_sub_body_contents(struct atom_value *val, int deref, void *buf)
1296 {
1297         int i;
1298         const char *subpos = NULL, *bodypos = NULL, *sigpos = NULL;
1299         size_t sublen = 0, bodylen = 0, nonsiglen = 0, siglen = 0;
1300
1301         for (i = 0; i < used_atom_cnt; i++) {
1302                 struct used_atom *atom = &used_atom[i];
1303                 const char *name = atom->name;
1304                 struct atom_value *v = &val[i];
1305
1306                 if (!!deref != (*name == '*'))
1307                         continue;
1308                 if (deref)
1309                         name++;
1310                 if (strcmp(name, "body") &&
1311                     !starts_with(name, "subject") &&
1312                     !starts_with(name, "trailers") &&
1313                     !starts_with(name, "contents"))
1314                         continue;
1315                 if (!subpos)
1316                         find_subpos(buf,
1317                                     &subpos, &sublen,
1318                                     &bodypos, &bodylen, &nonsiglen,
1319                                     &sigpos, &siglen);
1320
1321                 if (atom->u.contents.option == C_SUB)
1322                         v->s = copy_subject(subpos, sublen);
1323                 else if (atom->u.contents.option == C_SUB_SANITIZE) {
1324                         struct strbuf sb = STRBUF_INIT;
1325                         format_sanitized_subject(&sb, subpos, sublen);
1326                         v->s = strbuf_detach(&sb, NULL);
1327                 } else if (atom->u.contents.option == C_BODY_DEP)
1328                         v->s = xmemdupz(bodypos, bodylen);
1329                 else if (atom->u.contents.option == C_LENGTH)
1330                         v->s = xstrfmt("%"PRIuMAX, (uintmax_t)strlen(subpos));
1331                 else if (atom->u.contents.option == C_BODY)
1332                         v->s = xmemdupz(bodypos, nonsiglen);
1333                 else if (atom->u.contents.option == C_SIG)
1334                         v->s = xmemdupz(sigpos, siglen);
1335                 else if (atom->u.contents.option == C_LINES) {
1336                         struct strbuf s = STRBUF_INIT;
1337                         const char *contents_end = bodypos + nonsiglen;
1338
1339                         /*  Size is the length of the message after removing the signature */
1340                         append_lines(&s, subpos, contents_end - subpos, atom->u.contents.nlines);
1341                         v->s = strbuf_detach(&s, NULL);
1342                 } else if (atom->u.contents.option == C_TRAILERS) {
1343                         struct strbuf s = STRBUF_INIT;
1344
1345                         /* Format the trailer info according to the trailer_opts given */
1346                         format_trailers_from_commit(&s, subpos, &atom->u.contents.trailer_opts);
1347
1348                         v->s = strbuf_detach(&s, NULL);
1349                 } else if (atom->u.contents.option == C_BARE)
1350                         v->s = xstrdup(subpos);
1351
1352         }
1353         free((void *)sigpos);
1354 }
1355
1356 /*
1357  * We want to have empty print-string for field requests
1358  * that do not apply (e.g. "authordate" for a tag object)
1359  */
1360 static void fill_missing_values(struct atom_value *val)
1361 {
1362         int i;
1363         for (i = 0; i < used_atom_cnt; i++) {
1364                 struct atom_value *v = &val[i];
1365                 if (v->s == NULL)
1366                         v->s = xstrdup("");
1367         }
1368 }
1369
1370 /*
1371  * val is a list of atom_value to hold returned values.  Extract
1372  * the values for atoms in used_atom array out of (obj, buf, sz).
1373  * when deref is false, (obj, buf, sz) is the object that is
1374  * pointed at by the ref itself; otherwise it is the object the
1375  * ref (which is a tag) refers to.
1376  */
1377 static void grab_values(struct atom_value *val, int deref, struct object *obj, void *buf)
1378 {
1379         switch (obj->type) {
1380         case OBJ_TAG:
1381                 grab_tag_values(val, deref, obj);
1382                 grab_sub_body_contents(val, deref, buf);
1383                 grab_person("tagger", val, deref, buf);
1384                 break;
1385         case OBJ_COMMIT:
1386                 grab_commit_values(val, deref, obj);
1387                 grab_sub_body_contents(val, deref, buf);
1388                 grab_person("author", val, deref, buf);
1389                 grab_person("committer", val, deref, buf);
1390                 break;
1391         case OBJ_TREE:
1392                 /* grab_tree_values(val, deref, obj, buf, sz); */
1393                 break;
1394         case OBJ_BLOB:
1395                 /* grab_blob_values(val, deref, obj, buf, sz); */
1396                 break;
1397         default:
1398                 die("Eh?  Object of type %d?", obj->type);
1399         }
1400 }
1401
1402 static inline char *copy_advance(char *dst, const char *src)
1403 {
1404         while (*src)
1405                 *dst++ = *src++;
1406         return dst;
1407 }
1408
1409 static const char *lstrip_ref_components(const char *refname, int len)
1410 {
1411         long remaining = len;
1412         const char *start = xstrdup(refname);
1413         const char *to_free = start;
1414
1415         if (len < 0) {
1416                 int i;
1417                 const char *p = refname;
1418
1419                 /* Find total no of '/' separated path-components */
1420                 for (i = 0; p[i]; p[i] == '/' ? i++ : *p++)
1421                         ;
1422                 /*
1423                  * The number of components we need to strip is now
1424                  * the total minus the components to be left (Plus one
1425                  * because we count the number of '/', but the number
1426                  * of components is one more than the no of '/').
1427                  */
1428                 remaining = i + len + 1;
1429         }
1430
1431         while (remaining > 0) {
1432                 switch (*start++) {
1433                 case '\0':
1434                         free((char *)to_free);
1435                         return xstrdup("");
1436                 case '/':
1437                         remaining--;
1438                         break;
1439                 }
1440         }
1441
1442         start = xstrdup(start);
1443         free((char *)to_free);
1444         return start;
1445 }
1446
1447 static const char *rstrip_ref_components(const char *refname, int len)
1448 {
1449         long remaining = len;
1450         const char *start = xstrdup(refname);
1451         const char *to_free = start;
1452
1453         if (len < 0) {
1454                 int i;
1455                 const char *p = refname;
1456
1457                 /* Find total no of '/' separated path-components */
1458                 for (i = 0; p[i]; p[i] == '/' ? i++ : *p++)
1459                         ;
1460                 /*
1461                  * The number of components we need to strip is now
1462                  * the total minus the components to be left (Plus one
1463                  * because we count the number of '/', but the number
1464                  * of components is one more than the no of '/').
1465                  */
1466                 remaining = i + len + 1;
1467         }
1468
1469         while (remaining-- > 0) {
1470                 char *p = strrchr(start, '/');
1471                 if (p == NULL) {
1472                         free((char *)to_free);
1473                         return xstrdup("");
1474                 } else
1475                         p[0] = '\0';
1476         }
1477         return start;
1478 }
1479
1480 static const char *show_ref(struct refname_atom *atom, const char *refname)
1481 {
1482         if (atom->option == R_SHORT)
1483                 return shorten_unambiguous_ref(refname, warn_ambiguous_refs);
1484         else if (atom->option == R_LSTRIP)
1485                 return lstrip_ref_components(refname, atom->lstrip);
1486         else if (atom->option == R_RSTRIP)
1487                 return rstrip_ref_components(refname, atom->rstrip);
1488         else
1489                 return xstrdup(refname);
1490 }
1491
1492 static void fill_remote_ref_details(struct used_atom *atom, const char *refname,
1493                                     struct branch *branch, const char **s)
1494 {
1495         int num_ours, num_theirs;
1496         if (atom->u.remote_ref.option == RR_REF)
1497                 *s = show_ref(&atom->u.remote_ref.refname, refname);
1498         else if (atom->u.remote_ref.option == RR_TRACK) {
1499                 if (stat_tracking_info(branch, &num_ours, &num_theirs,
1500                                        NULL, atom->u.remote_ref.push,
1501                                        AHEAD_BEHIND_FULL) < 0) {
1502                         *s = xstrdup(msgs.gone);
1503                 } else if (!num_ours && !num_theirs)
1504                         *s = xstrdup("");
1505                 else if (!num_ours)
1506                         *s = xstrfmt(msgs.behind, num_theirs);
1507                 else if (!num_theirs)
1508                         *s = xstrfmt(msgs.ahead, num_ours);
1509                 else
1510                         *s = xstrfmt(msgs.ahead_behind,
1511                                      num_ours, num_theirs);
1512                 if (!atom->u.remote_ref.nobracket && *s[0]) {
1513                         const char *to_free = *s;
1514                         *s = xstrfmt("[%s]", *s);
1515                         free((void *)to_free);
1516                 }
1517         } else if (atom->u.remote_ref.option == RR_TRACKSHORT) {
1518                 if (stat_tracking_info(branch, &num_ours, &num_theirs,
1519                                        NULL, atom->u.remote_ref.push,
1520                                        AHEAD_BEHIND_FULL) < 0) {
1521                         *s = xstrdup("");
1522                         return;
1523                 }
1524                 if (!num_ours && !num_theirs)
1525                         *s = xstrdup("=");
1526                 else if (!num_ours)
1527                         *s = xstrdup("<");
1528                 else if (!num_theirs)
1529                         *s = xstrdup(">");
1530                 else
1531                         *s = xstrdup("<>");
1532         } else if (atom->u.remote_ref.option == RR_REMOTE_NAME) {
1533                 int explicit;
1534                 const char *remote = atom->u.remote_ref.push ?
1535                         pushremote_for_branch(branch, &explicit) :
1536                         remote_for_branch(branch, &explicit);
1537                 *s = xstrdup(explicit ? remote : "");
1538         } else if (atom->u.remote_ref.option == RR_REMOTE_REF) {
1539                 const char *merge;
1540
1541                 merge = remote_ref_for_branch(branch, atom->u.remote_ref.push);
1542                 *s = xstrdup(merge ? merge : "");
1543         } else
1544                 BUG("unhandled RR_* enum");
1545 }
1546
1547 char *get_head_description(void)
1548 {
1549         struct strbuf desc = STRBUF_INIT;
1550         struct wt_status_state state;
1551         memset(&state, 0, sizeof(state));
1552         wt_status_get_state(the_repository, &state, 1);
1553         if (state.rebase_in_progress ||
1554             state.rebase_interactive_in_progress) {
1555                 if (state.branch)
1556                         strbuf_addf(&desc, _("(no branch, rebasing %s)"),
1557                                     state.branch);
1558                 else
1559                         strbuf_addf(&desc, _("(no branch, rebasing detached HEAD %s)"),
1560                                     state.detached_from);
1561         } else if (state.bisect_in_progress)
1562                 strbuf_addf(&desc, _("(no branch, bisect started on %s)"),
1563                             state.branch);
1564         else if (state.detached_from) {
1565                 if (state.detached_at)
1566                         strbuf_addf(&desc, _("(HEAD detached at %s)"),
1567                                 state.detached_from);
1568                 else
1569                         strbuf_addf(&desc, _("(HEAD detached from %s)"),
1570                                 state.detached_from);
1571         } else
1572                 strbuf_addstr(&desc, _("(no branch)"));
1573
1574         return strbuf_detach(&desc, NULL);
1575 }
1576
1577 static const char *get_symref(struct used_atom *atom, struct ref_array_item *ref)
1578 {
1579         if (!ref->symref)
1580                 return xstrdup("");
1581         else
1582                 return show_ref(&atom->u.refname, ref->symref);
1583 }
1584
1585 static const char *get_refname(struct used_atom *atom, struct ref_array_item *ref)
1586 {
1587         if (ref->kind & FILTER_REFS_DETACHED_HEAD)
1588                 return get_head_description();
1589         return show_ref(&atom->u.refname, ref->refname);
1590 }
1591
1592 static int get_object(struct ref_array_item *ref, int deref, struct object **obj,
1593                       struct expand_data *oi, struct strbuf *err)
1594 {
1595         /* parse_object_buffer() will set eaten to 0 if free() will be needed */
1596         int eaten = 1;
1597         if (oi->info.contentp) {
1598                 /* We need to know that to use parse_object_buffer properly */
1599                 oi->info.sizep = &oi->size;
1600                 oi->info.typep = &oi->type;
1601         }
1602         if (oid_object_info_extended(the_repository, &oi->oid, &oi->info,
1603                                      OBJECT_INFO_LOOKUP_REPLACE))
1604                 return strbuf_addf_ret(err, -1, _("missing object %s for %s"),
1605                                        oid_to_hex(&oi->oid), ref->refname);
1606         if (oi->info.disk_sizep && oi->disk_size < 0)
1607                 BUG("Object size is less than zero.");
1608
1609         if (oi->info.contentp) {
1610                 *obj = parse_object_buffer(the_repository, &oi->oid, oi->type, oi->size, oi->content, &eaten);
1611                 if (!*obj) {
1612                         if (!eaten)
1613                                 free(oi->content);
1614                         return strbuf_addf_ret(err, -1, _("parse_object_buffer failed on %s for %s"),
1615                                                oid_to_hex(&oi->oid), ref->refname);
1616                 }
1617                 grab_values(ref->value, deref, *obj, oi->content);
1618         }
1619
1620         grab_common_values(ref->value, deref, oi);
1621         if (!eaten)
1622                 free(oi->content);
1623         return 0;
1624 }
1625
1626 static void populate_worktree_map(struct hashmap *map, struct worktree **worktrees)
1627 {
1628         int i;
1629
1630         for (i = 0; worktrees[i]; i++) {
1631                 if (worktrees[i]->head_ref) {
1632                         struct ref_to_worktree_entry *entry;
1633                         entry = xmalloc(sizeof(*entry));
1634                         entry->wt = worktrees[i];
1635                         hashmap_entry_init(&entry->ent,
1636                                         strhash(worktrees[i]->head_ref));
1637
1638                         hashmap_add(map, &entry->ent);
1639                 }
1640         }
1641 }
1642
1643 static void lazy_init_worktree_map(void)
1644 {
1645         if (ref_to_worktree_map.worktrees)
1646                 return;
1647
1648         ref_to_worktree_map.worktrees = get_worktrees();
1649         hashmap_init(&(ref_to_worktree_map.map), ref_to_worktree_map_cmpfnc, NULL, 0);
1650         populate_worktree_map(&(ref_to_worktree_map.map), ref_to_worktree_map.worktrees);
1651 }
1652
1653 static char *get_worktree_path(const struct used_atom *atom, const struct ref_array_item *ref)
1654 {
1655         struct hashmap_entry entry, *e;
1656         struct ref_to_worktree_entry *lookup_result;
1657
1658         lazy_init_worktree_map();
1659
1660         hashmap_entry_init(&entry, strhash(ref->refname));
1661         e = hashmap_get(&(ref_to_worktree_map.map), &entry, ref->refname);
1662
1663         if (!e)
1664                 return xstrdup("");
1665
1666         lookup_result = container_of(e, struct ref_to_worktree_entry, ent);
1667
1668         return xstrdup(lookup_result->wt->path);
1669 }
1670
1671 /*
1672  * Parse the object referred by ref, and grab needed value.
1673  */
1674 static int populate_value(struct ref_array_item *ref, struct strbuf *err)
1675 {
1676         struct object *obj;
1677         int i;
1678         struct object_info empty = OBJECT_INFO_INIT;
1679
1680         CALLOC_ARRAY(ref->value, used_atom_cnt);
1681
1682         if (need_symref && (ref->flag & REF_ISSYMREF) && !ref->symref) {
1683                 ref->symref = resolve_refdup(ref->refname, RESOLVE_REF_READING,
1684                                              NULL, NULL);
1685                 if (!ref->symref)
1686                         ref->symref = xstrdup("");
1687         }
1688
1689         /* Fill in specials first */
1690         for (i = 0; i < used_atom_cnt; i++) {
1691                 struct used_atom *atom = &used_atom[i];
1692                 const char *name = used_atom[i].name;
1693                 struct atom_value *v = &ref->value[i];
1694                 int deref = 0;
1695                 const char *refname;
1696                 struct branch *branch = NULL;
1697
1698                 v->handler = append_atom;
1699                 v->atom = atom;
1700
1701                 if (*name == '*') {
1702                         deref = 1;
1703                         name++;
1704                 }
1705
1706                 if (starts_with(name, "refname"))
1707                         refname = get_refname(atom, ref);
1708                 else if (!strcmp(name, "worktreepath")) {
1709                         if (ref->kind == FILTER_REFS_BRANCHES)
1710                                 v->s = get_worktree_path(atom, ref);
1711                         else
1712                                 v->s = xstrdup("");
1713                         continue;
1714                 }
1715                 else if (starts_with(name, "symref"))
1716                         refname = get_symref(atom, ref);
1717                 else if (starts_with(name, "upstream")) {
1718                         const char *branch_name;
1719                         /* only local branches may have an upstream */
1720                         if (!skip_prefix(ref->refname, "refs/heads/",
1721                                          &branch_name)) {
1722                                 v->s = xstrdup("");
1723                                 continue;
1724                         }
1725                         branch = branch_get(branch_name);
1726
1727                         refname = branch_get_upstream(branch, NULL);
1728                         if (refname)
1729                                 fill_remote_ref_details(atom, refname, branch, &v->s);
1730                         else
1731                                 v->s = xstrdup("");
1732                         continue;
1733                 } else if (!strcmp(atom->name, "push") || starts_with(atom->name, "push:")) {
1734                         const char *branch_name;
1735                         v->s = xstrdup("");
1736                         if (!skip_prefix(ref->refname, "refs/heads/",
1737                                          &branch_name))
1738                                 continue;
1739                         branch = branch_get(branch_name);
1740
1741                         if (atom->u.remote_ref.push_remote)
1742                                 refname = NULL;
1743                         else {
1744                                 refname = branch_get_push(branch, NULL);
1745                                 if (!refname)
1746                                         continue;
1747                         }
1748                         /* We will definitely re-init v->s on the next line. */
1749                         free((char *)v->s);
1750                         fill_remote_ref_details(atom, refname, branch, &v->s);
1751                         continue;
1752                 } else if (starts_with(name, "color:")) {
1753                         v->s = xstrdup(atom->u.color);
1754                         continue;
1755                 } else if (!strcmp(name, "flag")) {
1756                         char buf[256], *cp = buf;
1757                         if (ref->flag & REF_ISSYMREF)
1758                                 cp = copy_advance(cp, ",symref");
1759                         if (ref->flag & REF_ISPACKED)
1760                                 cp = copy_advance(cp, ",packed");
1761                         if (cp == buf)
1762                                 v->s = xstrdup("");
1763                         else {
1764                                 *cp = '\0';
1765                                 v->s = xstrdup(buf + 1);
1766                         }
1767                         continue;
1768                 } else if (!deref && grab_oid(name, "objectname", &ref->objectname, v, atom)) {
1769                         continue;
1770                 } else if (!strcmp(name, "HEAD")) {
1771                         if (atom->u.head && !strcmp(ref->refname, atom->u.head))
1772                                 v->s = xstrdup("*");
1773                         else
1774                                 v->s = xstrdup(" ");
1775                         continue;
1776                 } else if (starts_with(name, "align")) {
1777                         v->handler = align_atom_handler;
1778                         v->s = xstrdup("");
1779                         continue;
1780                 } else if (!strcmp(name, "end")) {
1781                         v->handler = end_atom_handler;
1782                         v->s = xstrdup("");
1783                         continue;
1784                 } else if (starts_with(name, "if")) {
1785                         const char *s;
1786                         if (skip_prefix(name, "if:", &s))
1787                                 v->s = xstrdup(s);
1788                         else
1789                                 v->s = xstrdup("");
1790                         v->handler = if_atom_handler;
1791                         continue;
1792                 } else if (!strcmp(name, "then")) {
1793                         v->handler = then_atom_handler;
1794                         v->s = xstrdup("");
1795                         continue;
1796                 } else if (!strcmp(name, "else")) {
1797                         v->handler = else_atom_handler;
1798                         v->s = xstrdup("");
1799                         continue;
1800                 } else
1801                         continue;
1802
1803                 if (!deref)
1804                         v->s = xstrdup(refname);
1805                 else
1806                         v->s = xstrfmt("%s^{}", refname);
1807                 free((char *)refname);
1808         }
1809
1810         for (i = 0; i < used_atom_cnt; i++) {
1811                 struct atom_value *v = &ref->value[i];
1812                 if (v->s == NULL && used_atom[i].source == SOURCE_NONE)
1813                         return strbuf_addf_ret(err, -1, _("missing object %s for %s"),
1814                                                oid_to_hex(&ref->objectname), ref->refname);
1815         }
1816
1817         if (need_tagged)
1818                 oi.info.contentp = &oi.content;
1819         if (!memcmp(&oi.info, &empty, sizeof(empty)) &&
1820             !memcmp(&oi_deref.info, &empty, sizeof(empty)))
1821                 return 0;
1822
1823
1824         oi.oid = ref->objectname;
1825         if (get_object(ref, 0, &obj, &oi, err))
1826                 return -1;
1827
1828         /*
1829          * If there is no atom that wants to know about tagged
1830          * object, we are done.
1831          */
1832         if (!need_tagged || (obj->type != OBJ_TAG))
1833                 return 0;
1834
1835         /*
1836          * If it is a tag object, see if we use a value that derefs
1837          * the object, and if we do grab the object it refers to.
1838          */
1839         oi_deref.oid = *get_tagged_oid((struct tag *)obj);
1840
1841         /*
1842          * NEEDSWORK: This derefs tag only once, which
1843          * is good to deal with chains of trust, but
1844          * is not consistent with what deref_tag() does
1845          * which peels the onion to the core.
1846          */
1847         return get_object(ref, 1, &obj, &oi_deref, err);
1848 }
1849
1850 /*
1851  * Given a ref, return the value for the atom.  This lazily gets value
1852  * out of the object by calling populate value.
1853  */
1854 static int get_ref_atom_value(struct ref_array_item *ref, int atom,
1855                               struct atom_value **v, struct strbuf *err)
1856 {
1857         if (!ref->value) {
1858                 if (populate_value(ref, err))
1859                         return -1;
1860                 fill_missing_values(ref->value);
1861         }
1862         *v = &ref->value[atom];
1863         return 0;
1864 }
1865
1866 /*
1867  * Return 1 if the refname matches one of the patterns, otherwise 0.
1868  * A pattern can be a literal prefix (e.g. a refname "refs/heads/master"
1869  * matches a pattern "refs/heads/mas") or a wildcard (e.g. the same ref
1870  * matches "refs/heads/mas*", too).
1871  */
1872 static int match_pattern(const struct ref_filter *filter, const char *refname)
1873 {
1874         const char **patterns = filter->name_patterns;
1875         unsigned flags = 0;
1876
1877         if (filter->ignore_case)
1878                 flags |= WM_CASEFOLD;
1879
1880         /*
1881          * When no '--format' option is given we need to skip the prefix
1882          * for matching refs of tags and branches.
1883          */
1884         (void)(skip_prefix(refname, "refs/tags/", &refname) ||
1885                skip_prefix(refname, "refs/heads/", &refname) ||
1886                skip_prefix(refname, "refs/remotes/", &refname) ||
1887                skip_prefix(refname, "refs/", &refname));
1888
1889         for (; *patterns; patterns++) {
1890                 if (!wildmatch(*patterns, refname, flags))
1891                         return 1;
1892         }
1893         return 0;
1894 }
1895
1896 /*
1897  * Return 1 if the refname matches one of the patterns, otherwise 0.
1898  * A pattern can be path prefix (e.g. a refname "refs/heads/master"
1899  * matches a pattern "refs/heads/" but not "refs/heads/m") or a
1900  * wildcard (e.g. the same ref matches "refs/heads/m*", too).
1901  */
1902 static int match_name_as_path(const struct ref_filter *filter, const char *refname)
1903 {
1904         const char **pattern = filter->name_patterns;
1905         int namelen = strlen(refname);
1906         unsigned flags = WM_PATHNAME;
1907
1908         if (filter->ignore_case)
1909                 flags |= WM_CASEFOLD;
1910
1911         for (; *pattern; pattern++) {
1912                 const char *p = *pattern;
1913                 int plen = strlen(p);
1914
1915                 if ((plen <= namelen) &&
1916                     !strncmp(refname, p, plen) &&
1917                     (refname[plen] == '\0' ||
1918                      refname[plen] == '/' ||
1919                      p[plen-1] == '/'))
1920                         return 1;
1921                 if (!wildmatch(p, refname, flags))
1922                         return 1;
1923         }
1924         return 0;
1925 }
1926
1927 /* Return 1 if the refname matches one of the patterns, otherwise 0. */
1928 static int filter_pattern_match(struct ref_filter *filter, const char *refname)
1929 {
1930         if (!*filter->name_patterns)
1931                 return 1; /* No pattern always matches */
1932         if (filter->match_as_path)
1933                 return match_name_as_path(filter, refname);
1934         return match_pattern(filter, refname);
1935 }
1936
1937 /*
1938  * This is the same as for_each_fullref_in(), but it tries to iterate
1939  * only over the patterns we'll care about. Note that it _doesn't_ do a full
1940  * pattern match, so the callback still has to match each ref individually.
1941  */
1942 static int for_each_fullref_in_pattern(struct ref_filter *filter,
1943                                        each_ref_fn cb,
1944                                        void *cb_data,
1945                                        int broken)
1946 {
1947         if (!filter->match_as_path) {
1948                 /*
1949                  * in this case, the patterns are applied after
1950                  * prefixes like "refs/heads/" etc. are stripped off,
1951                  * so we have to look at everything:
1952                  */
1953                 return for_each_fullref_in("", cb, cb_data, broken);
1954         }
1955
1956         if (filter->ignore_case) {
1957                 /*
1958                  * we can't handle case-insensitive comparisons,
1959                  * so just return everything and let the caller
1960                  * sort it out.
1961                  */
1962                 return for_each_fullref_in("", cb, cb_data, broken);
1963         }
1964
1965         if (!filter->name_patterns[0]) {
1966                 /* no patterns; we have to look at everything */
1967                 return for_each_fullref_in("", cb, cb_data, broken);
1968         }
1969
1970         return for_each_fullref_in_prefixes(NULL, filter->name_patterns,
1971                                             cb, cb_data, broken);
1972 }
1973
1974 /*
1975  * Given a ref (oid, refname), check if the ref belongs to the array
1976  * of oids. If the given ref is a tag, check if the given tag points
1977  * at one of the oids in the given oid array.
1978  * NEEDSWORK:
1979  * 1. Only a single level of indirection is obtained, we might want to
1980  * change this to account for multiple levels (e.g. annotated tags
1981  * pointing to annotated tags pointing to a commit.)
1982  * 2. As the refs are cached we might know what refname peels to without
1983  * the need to parse the object via parse_object(). peel_ref() might be a
1984  * more efficient alternative to obtain the pointee.
1985  */
1986 static const struct object_id *match_points_at(struct oid_array *points_at,
1987                                                const struct object_id *oid,
1988                                                const char *refname)
1989 {
1990         const struct object_id *tagged_oid = NULL;
1991         struct object *obj;
1992
1993         if (oid_array_lookup(points_at, oid) >= 0)
1994                 return oid;
1995         obj = parse_object(the_repository, oid);
1996         if (!obj)
1997                 die(_("malformed object at '%s'"), refname);
1998         if (obj->type == OBJ_TAG)
1999                 tagged_oid = get_tagged_oid((struct tag *)obj);
2000         if (tagged_oid && oid_array_lookup(points_at, tagged_oid) >= 0)
2001                 return tagged_oid;
2002         return NULL;
2003 }
2004
2005 /*
2006  * Allocate space for a new ref_array_item and copy the name and oid to it.
2007  *
2008  * Callers can then fill in other struct members at their leisure.
2009  */
2010 static struct ref_array_item *new_ref_array_item(const char *refname,
2011                                                  const struct object_id *oid)
2012 {
2013         struct ref_array_item *ref;
2014
2015         FLEX_ALLOC_STR(ref, refname, refname);
2016         oidcpy(&ref->objectname, oid);
2017
2018         return ref;
2019 }
2020
2021 struct ref_array_item *ref_array_push(struct ref_array *array,
2022                                       const char *refname,
2023                                       const struct object_id *oid)
2024 {
2025         struct ref_array_item *ref = new_ref_array_item(refname, oid);
2026
2027         ALLOC_GROW(array->items, array->nr + 1, array->alloc);
2028         array->items[array->nr++] = ref;
2029
2030         return ref;
2031 }
2032
2033 static int ref_kind_from_refname(const char *refname)
2034 {
2035         unsigned int i;
2036
2037         static struct {
2038                 const char *prefix;
2039                 unsigned int kind;
2040         } ref_kind[] = {
2041                 { "refs/heads/" , FILTER_REFS_BRANCHES },
2042                 { "refs/remotes/" , FILTER_REFS_REMOTES },
2043                 { "refs/tags/", FILTER_REFS_TAGS}
2044         };
2045
2046         if (!strcmp(refname, "HEAD"))
2047                 return FILTER_REFS_DETACHED_HEAD;
2048
2049         for (i = 0; i < ARRAY_SIZE(ref_kind); i++) {
2050                 if (starts_with(refname, ref_kind[i].prefix))
2051                         return ref_kind[i].kind;
2052         }
2053
2054         return FILTER_REFS_OTHERS;
2055 }
2056
2057 static int filter_ref_kind(struct ref_filter *filter, const char *refname)
2058 {
2059         if (filter->kind == FILTER_REFS_BRANCHES ||
2060             filter->kind == FILTER_REFS_REMOTES ||
2061             filter->kind == FILTER_REFS_TAGS)
2062                 return filter->kind;
2063         return ref_kind_from_refname(refname);
2064 }
2065
2066 struct ref_filter_cbdata {
2067         struct ref_array *array;
2068         struct ref_filter *filter;
2069         struct contains_cache contains_cache;
2070         struct contains_cache no_contains_cache;
2071 };
2072
2073 /*
2074  * A call-back given to for_each_ref().  Filter refs and keep them for
2075  * later object processing.
2076  */
2077 static int ref_filter_handler(const char *refname, const struct object_id *oid, int flag, void *cb_data)
2078 {
2079         struct ref_filter_cbdata *ref_cbdata = cb_data;
2080         struct ref_filter *filter = ref_cbdata->filter;
2081         struct ref_array_item *ref;
2082         struct commit *commit = NULL;
2083         unsigned int kind;
2084
2085         if (flag & REF_BAD_NAME) {
2086                 warning(_("ignoring ref with broken name %s"), refname);
2087                 return 0;
2088         }
2089
2090         if (flag & REF_ISBROKEN) {
2091                 warning(_("ignoring broken ref %s"), refname);
2092                 return 0;
2093         }
2094
2095         /* Obtain the current ref kind from filter_ref_kind() and ignore unwanted refs. */
2096         kind = filter_ref_kind(filter, refname);
2097         if (!(kind & filter->kind))
2098                 return 0;
2099
2100         if (!filter_pattern_match(filter, refname))
2101                 return 0;
2102
2103         if (filter->points_at.nr && !match_points_at(&filter->points_at, oid, refname))
2104                 return 0;
2105
2106         /*
2107          * A merge filter is applied on refs pointing to commits. Hence
2108          * obtain the commit using the 'oid' available and discard all
2109          * non-commits early. The actual filtering is done later.
2110          */
2111         if (filter->reachable_from || filter->unreachable_from ||
2112             filter->with_commit || filter->no_commit || filter->verbose) {
2113                 commit = lookup_commit_reference_gently(the_repository, oid, 1);
2114                 if (!commit)
2115                         return 0;
2116                 /* We perform the filtering for the '--contains' option... */
2117                 if (filter->with_commit &&
2118                     !commit_contains(filter, commit, filter->with_commit, &ref_cbdata->contains_cache))
2119                         return 0;
2120                 /* ...or for the `--no-contains' option */
2121                 if (filter->no_commit &&
2122                     commit_contains(filter, commit, filter->no_commit, &ref_cbdata->no_contains_cache))
2123                         return 0;
2124         }
2125
2126         /*
2127          * We do not open the object yet; sort may only need refname
2128          * to do its job and the resulting list may yet to be pruned
2129          * by maxcount logic.
2130          */
2131         ref = ref_array_push(ref_cbdata->array, refname, oid);
2132         ref->commit = commit;
2133         ref->flag = flag;
2134         ref->kind = kind;
2135
2136         return 0;
2137 }
2138
2139 /*  Free memory allocated for a ref_array_item */
2140 static void free_array_item(struct ref_array_item *item)
2141 {
2142         free((char *)item->symref);
2143         if (item->value) {
2144                 int i;
2145                 for (i = 0; i < used_atom_cnt; i++)
2146                         free((char *)item->value[i].s);
2147                 free(item->value);
2148         }
2149         free(item);
2150 }
2151
2152 /* Free all memory allocated for ref_array */
2153 void ref_array_clear(struct ref_array *array)
2154 {
2155         int i;
2156
2157         for (i = 0; i < array->nr; i++)
2158                 free_array_item(array->items[i]);
2159         FREE_AND_NULL(array->items);
2160         array->nr = array->alloc = 0;
2161
2162         for (i = 0; i < used_atom_cnt; i++)
2163                 free((char *)used_atom[i].name);
2164         FREE_AND_NULL(used_atom);
2165         used_atom_cnt = 0;
2166
2167         if (ref_to_worktree_map.worktrees) {
2168                 hashmap_clear_and_free(&(ref_to_worktree_map.map),
2169                                         struct ref_to_worktree_entry, ent);
2170                 free_worktrees(ref_to_worktree_map.worktrees);
2171                 ref_to_worktree_map.worktrees = NULL;
2172         }
2173 }
2174
2175 #define EXCLUDE_REACHED 0
2176 #define INCLUDE_REACHED 1
2177 static void reach_filter(struct ref_array *array,
2178                          struct commit_list *check_reachable,
2179                          int include_reached)
2180 {
2181         struct rev_info revs;
2182         int i, old_nr;
2183         struct commit **to_clear;
2184         struct commit_list *cr;
2185
2186         if (!check_reachable)
2187                 return;
2188
2189         CALLOC_ARRAY(to_clear, array->nr);
2190
2191         repo_init_revisions(the_repository, &revs, NULL);
2192
2193         for (i = 0; i < array->nr; i++) {
2194                 struct ref_array_item *item = array->items[i];
2195                 add_pending_object(&revs, &item->commit->object, item->refname);
2196                 to_clear[i] = item->commit;
2197         }
2198
2199         for (cr = check_reachable; cr; cr = cr->next) {
2200                 struct commit *merge_commit = cr->item;
2201                 merge_commit->object.flags |= UNINTERESTING;
2202                 add_pending_object(&revs, &merge_commit->object, "");
2203         }
2204
2205         revs.limited = 1;
2206         if (prepare_revision_walk(&revs))
2207                 die(_("revision walk setup failed"));
2208
2209         old_nr = array->nr;
2210         array->nr = 0;
2211
2212         for (i = 0; i < old_nr; i++) {
2213                 struct ref_array_item *item = array->items[i];
2214                 struct commit *commit = item->commit;
2215
2216                 int is_merged = !!(commit->object.flags & UNINTERESTING);
2217
2218                 if (is_merged == include_reached)
2219                         array->items[array->nr++] = array->items[i];
2220                 else
2221                         free_array_item(item);
2222         }
2223
2224         clear_commit_marks_many(old_nr, to_clear, ALL_REV_FLAGS);
2225
2226         while (check_reachable) {
2227                 struct commit *merge_commit = pop_commit(&check_reachable);
2228                 clear_commit_marks(merge_commit, ALL_REV_FLAGS);
2229         }
2230
2231         free(to_clear);
2232 }
2233
2234 /*
2235  * API for filtering a set of refs. Based on the type of refs the user
2236  * has requested, we iterate through those refs and apply filters
2237  * as per the given ref_filter structure and finally store the
2238  * filtered refs in the ref_array structure.
2239  */
2240 int filter_refs(struct ref_array *array, struct ref_filter *filter, unsigned int type)
2241 {
2242         struct ref_filter_cbdata ref_cbdata;
2243         int ret = 0;
2244         unsigned int broken = 0;
2245
2246         ref_cbdata.array = array;
2247         ref_cbdata.filter = filter;
2248
2249         if (type & FILTER_REFS_INCLUDE_BROKEN)
2250                 broken = 1;
2251         filter->kind = type & FILTER_REFS_KIND_MASK;
2252
2253         init_contains_cache(&ref_cbdata.contains_cache);
2254         init_contains_cache(&ref_cbdata.no_contains_cache);
2255
2256         /*  Simple per-ref filtering */
2257         if (!filter->kind)
2258                 die("filter_refs: invalid type");
2259         else {
2260                 /*
2261                  * For common cases where we need only branches or remotes or tags,
2262                  * we only iterate through those refs. If a mix of refs is needed,
2263                  * we iterate over all refs and filter out required refs with the help
2264                  * of filter_ref_kind().
2265                  */
2266                 if (filter->kind == FILTER_REFS_BRANCHES)
2267                         ret = for_each_fullref_in("refs/heads/", ref_filter_handler, &ref_cbdata, broken);
2268                 else if (filter->kind == FILTER_REFS_REMOTES)
2269                         ret = for_each_fullref_in("refs/remotes/", ref_filter_handler, &ref_cbdata, broken);
2270                 else if (filter->kind == FILTER_REFS_TAGS)
2271                         ret = for_each_fullref_in("refs/tags/", ref_filter_handler, &ref_cbdata, broken);
2272                 else if (filter->kind & FILTER_REFS_ALL)
2273                         ret = for_each_fullref_in_pattern(filter, ref_filter_handler, &ref_cbdata, broken);
2274                 if (!ret && (filter->kind & FILTER_REFS_DETACHED_HEAD))
2275                         head_ref(ref_filter_handler, &ref_cbdata);
2276         }
2277
2278         clear_contains_cache(&ref_cbdata.contains_cache);
2279         clear_contains_cache(&ref_cbdata.no_contains_cache);
2280
2281         /*  Filters that need revision walking */
2282         reach_filter(array, filter->reachable_from, INCLUDE_REACHED);
2283         reach_filter(array, filter->unreachable_from, EXCLUDE_REACHED);
2284
2285         return ret;
2286 }
2287
2288 static int compare_detached_head(struct ref_array_item *a, struct ref_array_item *b)
2289 {
2290         if (!(a->kind ^ b->kind))
2291                 BUG("ref_kind_from_refname() should only mark one ref as HEAD");
2292         if (a->kind & FILTER_REFS_DETACHED_HEAD)
2293                 return -1;
2294         else if (b->kind & FILTER_REFS_DETACHED_HEAD)
2295                 return 1;
2296         BUG("should have died in the xor check above");
2297         return 0;
2298 }
2299
2300 static int cmp_ref_sorting(struct ref_sorting *s, struct ref_array_item *a, struct ref_array_item *b)
2301 {
2302         struct atom_value *va, *vb;
2303         int cmp;
2304         int cmp_detached_head = 0;
2305         cmp_type cmp_type = used_atom[s->atom].type;
2306         struct strbuf err = STRBUF_INIT;
2307
2308         if (get_ref_atom_value(a, s->atom, &va, &err))
2309                 die("%s", err.buf);
2310         if (get_ref_atom_value(b, s->atom, &vb, &err))
2311                 die("%s", err.buf);
2312         strbuf_release(&err);
2313         if (s->sort_flags & REF_SORTING_DETACHED_HEAD_FIRST &&
2314             ((a->kind | b->kind) & FILTER_REFS_DETACHED_HEAD)) {
2315                 cmp = compare_detached_head(a, b);
2316                 cmp_detached_head = 1;
2317         } else if (s->sort_flags & REF_SORTING_VERSION) {
2318                 cmp = versioncmp(va->s, vb->s);
2319         } else if (cmp_type == FIELD_STR) {
2320                 int (*cmp_fn)(const char *, const char *);
2321                 cmp_fn = s->sort_flags & REF_SORTING_ICASE
2322                         ? strcasecmp : strcmp;
2323                 cmp = cmp_fn(va->s, vb->s);
2324         } else {
2325                 if (va->value < vb->value)
2326                         cmp = -1;
2327                 else if (va->value == vb->value)
2328                         cmp = 0;
2329                 else
2330                         cmp = 1;
2331         }
2332
2333         return (s->sort_flags & REF_SORTING_REVERSE && !cmp_detached_head)
2334                 ? -cmp : cmp;
2335 }
2336
2337 static int compare_refs(const void *a_, const void *b_, void *ref_sorting)
2338 {
2339         struct ref_array_item *a = *((struct ref_array_item **)a_);
2340         struct ref_array_item *b = *((struct ref_array_item **)b_);
2341         struct ref_sorting *s;
2342
2343         for (s = ref_sorting; s; s = s->next) {
2344                 int cmp = cmp_ref_sorting(s, a, b);
2345                 if (cmp)
2346                         return cmp;
2347         }
2348         s = ref_sorting;
2349         return s && s->sort_flags & REF_SORTING_ICASE ?
2350                 strcasecmp(a->refname, b->refname) :
2351                 strcmp(a->refname, b->refname);
2352 }
2353
2354 void ref_sorting_set_sort_flags_all(struct ref_sorting *sorting,
2355                                     unsigned int mask, int on)
2356 {
2357         for (; sorting; sorting = sorting->next) {
2358                 if (on)
2359                         sorting->sort_flags |= mask;
2360                 else
2361                         sorting->sort_flags &= ~mask;
2362         }
2363 }
2364
2365 void ref_array_sort(struct ref_sorting *sorting, struct ref_array *array)
2366 {
2367         QSORT_S(array->items, array->nr, compare_refs, sorting);
2368 }
2369
2370 static void append_literal(const char *cp, const char *ep, struct ref_formatting_state *state)
2371 {
2372         struct strbuf *s = &state->stack->output;
2373
2374         while (*cp && (!ep || cp < ep)) {
2375                 if (*cp == '%') {
2376                         if (cp[1] == '%')
2377                                 cp++;
2378                         else {
2379                                 int ch = hex2chr(cp + 1);
2380                                 if (0 <= ch) {
2381                                         strbuf_addch(s, ch);
2382                                         cp += 3;
2383                                         continue;
2384                                 }
2385                         }
2386                 }
2387                 strbuf_addch(s, *cp);
2388                 cp++;
2389         }
2390 }
2391
2392 int format_ref_array_item(struct ref_array_item *info,
2393                            const struct ref_format *format,
2394                            struct strbuf *final_buf,
2395                            struct strbuf *error_buf)
2396 {
2397         const char *cp, *sp, *ep;
2398         struct ref_formatting_state state = REF_FORMATTING_STATE_INIT;
2399
2400         state.quote_style = format->quote_style;
2401         push_stack_element(&state.stack);
2402
2403         for (cp = format->format; *cp && (sp = find_next(cp)); cp = ep + 1) {
2404                 struct atom_value *atomv;
2405                 int pos;
2406
2407                 ep = strchr(sp, ')');
2408                 if (cp < sp)
2409                         append_literal(cp, sp, &state);
2410                 pos = parse_ref_filter_atom(format, sp + 2, ep, error_buf);
2411                 if (pos < 0 || get_ref_atom_value(info, pos, &atomv, error_buf) ||
2412                     atomv->handler(atomv, &state, error_buf)) {
2413                         pop_stack_element(&state.stack);
2414                         return -1;
2415                 }
2416         }
2417         if (*cp) {
2418                 sp = cp + strlen(cp);
2419                 append_literal(cp, sp, &state);
2420         }
2421         if (format->need_color_reset_at_eol) {
2422                 struct atom_value resetv;
2423                 resetv.s = GIT_COLOR_RESET;
2424                 if (append_atom(&resetv, &state, error_buf)) {
2425                         pop_stack_element(&state.stack);
2426                         return -1;
2427                 }
2428         }
2429         if (state.stack->prev) {
2430                 pop_stack_element(&state.stack);
2431                 return strbuf_addf_ret(error_buf, -1, _("format: %%(end) atom missing"));
2432         }
2433         strbuf_addbuf(final_buf, &state.stack->output);
2434         pop_stack_element(&state.stack);
2435         return 0;
2436 }
2437
2438 void pretty_print_ref(const char *name, const struct object_id *oid,
2439                       const struct ref_format *format)
2440 {
2441         struct ref_array_item *ref_item;
2442         struct strbuf output = STRBUF_INIT;
2443         struct strbuf err = STRBUF_INIT;
2444
2445         ref_item = new_ref_array_item(name, oid);
2446         ref_item->kind = ref_kind_from_refname(name);
2447         if (format_ref_array_item(ref_item, format, &output, &err))
2448                 die("%s", err.buf);
2449         fwrite(output.buf, 1, output.len, stdout);
2450         putchar('\n');
2451
2452         strbuf_release(&err);
2453         strbuf_release(&output);
2454         free_array_item(ref_item);
2455 }
2456
2457 static int parse_sorting_atom(const char *atom)
2458 {
2459         /*
2460          * This parses an atom using a dummy ref_format, since we don't
2461          * actually care about the formatting details.
2462          */
2463         struct ref_format dummy = REF_FORMAT_INIT;
2464         const char *end = atom + strlen(atom);
2465         struct strbuf err = STRBUF_INIT;
2466         int res = parse_ref_filter_atom(&dummy, atom, end, &err);
2467         if (res < 0)
2468                 die("%s", err.buf);
2469         strbuf_release(&err);
2470         return res;
2471 }
2472
2473 /*  If no sorting option is given, use refname to sort as default */
2474 struct ref_sorting *ref_default_sorting(void)
2475 {
2476         static const char cstr_name[] = "refname";
2477
2478         struct ref_sorting *sorting = xcalloc(1, sizeof(*sorting));
2479
2480         sorting->next = NULL;
2481         sorting->atom = parse_sorting_atom(cstr_name);
2482         return sorting;
2483 }
2484
2485 void parse_ref_sorting(struct ref_sorting **sorting_tail, const char *arg)
2486 {
2487         struct ref_sorting *s;
2488
2489         CALLOC_ARRAY(s, 1);
2490         s->next = *sorting_tail;
2491         *sorting_tail = s;
2492
2493         if (*arg == '-') {
2494                 s->sort_flags |= REF_SORTING_REVERSE;
2495                 arg++;
2496         }
2497         if (skip_prefix(arg, "version:", &arg) ||
2498             skip_prefix(arg, "v:", &arg))
2499                 s->sort_flags |= REF_SORTING_VERSION;
2500         s->atom = parse_sorting_atom(arg);
2501 }
2502
2503 int parse_opt_ref_sorting(const struct option *opt, const char *arg, int unset)
2504 {
2505         /*
2506          * NEEDSWORK: We should probably clear the list in this case, but we've
2507          * already munged the global used_atoms list, which would need to be
2508          * undone.
2509          */
2510         BUG_ON_OPT_NEG(unset);
2511
2512         parse_ref_sorting(opt->value, arg);
2513         return 0;
2514 }
2515
2516 int parse_opt_merge_filter(const struct option *opt, const char *arg, int unset)
2517 {
2518         struct ref_filter *rf = opt->value;
2519         struct object_id oid;
2520         struct commit *merge_commit;
2521
2522         BUG_ON_OPT_NEG(unset);
2523
2524         if (get_oid(arg, &oid))
2525                 die(_("malformed object name %s"), arg);
2526
2527         merge_commit = lookup_commit_reference_gently(the_repository, &oid, 0);
2528
2529         if (!merge_commit)
2530                 return error(_("option `%s' must point to a commit"), opt->long_name);
2531
2532         if (starts_with(opt->long_name, "no"))
2533                 commit_list_insert(merge_commit, &rf->unreachable_from);
2534         else
2535                 commit_list_insert(merge_commit, &rf->reachable_from);
2536
2537         return 0;
2538 }