builtin/for-each-ref.c

   1 #include "builtin.h"
   2 #include "cache.h"
   3 #include "refs.h"
   4 #include "object.h"
   5 #include "tag.h"
   6 #include "commit.h"
   7 #include "tree.h"
   8 #include "blob.h"
   9 #include "quote.h"
  10 #include "parse-options.h"
  11 #include "remote.h"
  12
  13 /* Quoting styles */
  14 #define QUOTE_NONE 0
  15 #define QUOTE_SHELL 1
  16 #define QUOTE_PERL 2
  17 #define QUOTE_PYTHON 4
  18 #define QUOTE_TCL 8
  19
  20 typedef enum { FIELD_STR, FIELD_ULONG, FIELD_TIME } cmp_type;
  21
  22 struct atom_value {
  23         const char *s;
  24         unsigned long ul; /* used for sorting when not FIELD_STR */
  25 };
  26
  27 struct ref_sort {
  28         struct ref_sort *next;
  29         int atom; /* index into used_atom array */
  30         unsigned reverse : 1;
  31 };
  32
  33 struct refinfo {
  34         char *refname;
  35         unsigned char objectname[20];
  36         int flag;
  37         const char *symref;
  38         struct atom_value *value;
  39 };
  40
  41 static struct {
  42         const char *name;
  43         cmp_type cmp_type;
  44 } valid_atom[] = {
  45         { "refname" },
  46         { "objecttype" },
  47         { "objectsize", FIELD_ULONG },
  48         { "objectname" },
  49         { "tree" },
  50         { "parent" },
  51         { "numparent", FIELD_ULONG },
  52         { "object" },
  53         { "type" },
  54         { "tag" },
  55         { "author" },
  56         { "authorname" },
  57         { "authoremail" },
  58         { "authordate", FIELD_TIME },
  59         { "committer" },
  60         { "committername" },
  61         { "committeremail" },
  62         { "committerdate", FIELD_TIME },
  63         { "tagger" },
  64         { "taggername" },
  65         { "taggeremail" },
  66         { "taggerdate", FIELD_TIME },
  67         { "creator" },
  68         { "creatordate", FIELD_TIME },
  69         { "subject" },
  70         { "body" },
  71         { "contents" },
  72         { "contents:subject" },
  73         { "contents:body" },
  74         { "contents:signature" },
  75         { "upstream" },
  76         { "symref" },
  77         { "flag" },
  78 };
  79
  80 /*
  81  * An atom is a valid field atom listed above, possibly prefixed with
  82  * a "*" to denote deref_tag().
  83  *
  84  * We parse given format string and sort specifiers, and make a list
  85  * of properties that we need to extract out of objects.  refinfo
  86  * structure will hold an array of values extracted that can be
  87  * indexed with the "atom number", which is an index into this
  88  * array.
  89  */
  90 static const char **used_atom;
  91 static cmp_type *used_atom_type;
  92 static int used_atom_cnt, sort_atom_limit, need_tagged, need_symref;
  93
  94 /*
  95  * Used to parse format string and sort specifiers
  96  */
  97 static int parse_atom(const char *atom, const char *ep)
  98 {
  99         const char *sp;
 100         int i, at;
 101
 102         sp = atom;
 103         if (*sp == '*' && sp < ep)
 104                 sp++; /* deref */
 105         if (ep <= sp)
 106                 die("malformed field name: %.*s", (int)(ep-atom), atom);
 107
 108         /* Do we have the atom already used elsewhere? */
 109         for (i = 0; i < used_atom_cnt; i++) {
 110                 int len = strlen(used_atom[i]);
 111                 if (len == ep - atom && !memcmp(used_atom[i], atom, len))
 112                         return i;
 113         }
 114
 115         /* Is the atom a valid one? */
 116         for (i = 0; i < ARRAY_SIZE(valid_atom); i++) {
 117                 int len = strlen(valid_atom[i].name);
 118                 /*
 119                  * If the atom name has a colon, strip it and everything after
 120                  * it off - it specifies the format for this entry, and
 121                  * shouldn't be used for checking against the valid_atom
 122                  * table.
 123                  */
 124                 const char *formatp = strchr(sp, ':');
 125                 if (!formatp || ep < formatp)
 126                         formatp = ep;
 127                 if (len == formatp - sp && !memcmp(valid_atom[i].name, sp, len))
 128                         break;
 129         }
 130
 131         if (ARRAY_SIZE(valid_atom) <= i)
 132                 die("unknown field name: %.*s", (int)(ep-atom), atom);
 133
 134         /* Add it in, including the deref prefix */
 135         at = used_atom_cnt;
 136         used_atom_cnt++;
 137         used_atom = xrealloc(used_atom,
 138                              (sizeof *used_atom) * used_atom_cnt);
 139         used_atom_type = xrealloc(used_atom_type,
 140                                   (sizeof(*used_atom_type) * used_atom_cnt));
 141         used_atom[at] = xmemdupz(atom, ep - atom);
 142         used_atom_type[at] = valid_atom[i].cmp_type;
 143         if (*atom == '*')
 144                 need_tagged = 1;
 145         if (!strcmp(used_atom[at], "symref"))
 146                 need_symref = 1;
 147         return at;
 148 }
 149
 150 /*
 151  * In a format string, find the next occurrence of %(atom).
 152  */
 153 static const char *find_next(const char *cp)
 154 {
 155         while (*cp) {
 156                 if (*cp == '%') {
 157                         /*
 158                          * %( is the start of an atom;
 159                          * %% is a quoted per-cent.
 160                          */
 161                         if (cp[1] == '(')
 162                                 return cp;
 163                         else if (cp[1] == '%')
 164                                 cp++; /* skip over two % */
 165                         /* otherwise this is a singleton, literal % */
 166                 }
 167                 cp++;
 168         }
 169         return NULL;
 170 }
 171
 172 /*
 173  * Make sure the format string is well formed, and parse out
 174  * the used atoms.
 175  */
 176 static int verify_format(const char *format)
 177 {
 178         const char *cp, *sp;
 179         for (cp = format; *cp && (sp = find_next(cp)); ) {
 180                 const char *ep = strchr(sp, ')');
 181                 if (!ep)
 182                         return error("malformed format string %s", sp);
 183                 /* sp points at "%(" and ep points at the closing ")" */
 184                 parse_atom(sp + 2, ep);
 185                 cp = ep + 1;
 186         }
 187         return 0;
 188 }
 189
 190 /*
 191  * Given an object name, read the object data and size, and return a
 192  * "struct object".  If the object data we are returning is also borrowed
 193  * by the "struct object" representation, set *eaten as well---it is a
 194  * signal from parse_object_buffer to us not to free the buffer.
 195  */
 196 static void *get_obj(const unsigned char *sha1, struct object **obj, unsigned long *sz, int *eaten)
 197 {
 198         enum object_type type;
 199         void *buf = read_sha1_file(sha1, &type, sz);
 200
 201         if (buf)
 202                 *obj = parse_object_buffer(sha1, type, *sz, buf, eaten);
 203         else
 204                 *obj = NULL;
 205         return buf;
 206 }
 207
 208 /* See grab_values */
 209 static void grab_common_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 210 {
 211         int i;
 212
 213         for (i = 0; i < used_atom_cnt; i++) {
 214                 const char *name = used_atom[i];
 215                 struct atom_value *v = &val[i];
 216                 if (!!deref != (*name == '*'))
 217                         continue;
 218                 if (deref)
 219                         name++;
 220                 if (!strcmp(name, "objecttype"))
 221                         v->s = typename(obj->type);
 222                 else if (!strcmp(name, "objectsize")) {
 223                         char *s = xmalloc(40);
 224                         sprintf(s, "%lu", sz);
 225                         v->ul = sz;
 226                         v->s = s;
 227                 }
 228                 else if (!strcmp(name, "objectname")) {
 229                         char *s = xmalloc(41);
 230                         strcpy(s, sha1_to_hex(obj->sha1));
 231                         v->s = s;
 232                 }
 233                 else if (!strcmp(name, "objectname:short")) {
 234                         v->s = xstrdup(find_unique_abbrev(obj->sha1,
 235                                                           DEFAULT_ABBREV));
 236                 }
 237         }
 238 }
 239
 240 /* See grab_values */
 241 static void grab_tag_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 242 {
 243         int i;
 244         struct tag *tag = (struct tag *) obj;
 245
 246         for (i = 0; i < used_atom_cnt; i++) {
 247                 const char *name = used_atom[i];
 248                 struct atom_value *v = &val[i];
 249                 if (!!deref != (*name == '*'))
 250                         continue;
 251                 if (deref)
 252                         name++;
 253                 if (!strcmp(name, "tag"))
 254                         v->s = tag->tag;
 255                 else if (!strcmp(name, "type") && tag->tagged)
 256                         v->s = typename(tag->tagged->type);
 257                 else if (!strcmp(name, "object") && tag->tagged) {
 258                         char *s = xmalloc(41);
 259                         strcpy(s, sha1_to_hex(tag->tagged->sha1));
 260                         v->s = s;
 261                 }
 262         }
 263 }
 264
 265 static int num_parents(struct commit *commit)
 266 {
 267         struct commit_list *parents;
 268         int i;
 269
 270         for (i = 0, parents = commit->parents;
 271              parents;
 272              parents = parents->next)
 273                 i++;
 274         return i;
 275 }
 276
 277 /* See grab_values */
 278 static void grab_commit_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 279 {
 280         int i;
 281         struct commit *commit = (struct commit *) obj;
 282
 283         for (i = 0; i < used_atom_cnt; i++) {
 284                 const char *name = used_atom[i];
 285                 struct atom_value *v = &val[i];
 286                 if (!!deref != (*name == '*'))
 287                         continue;
 288                 if (deref)
 289                         name++;
 290                 if (!strcmp(name, "tree")) {
 291                         char *s = xmalloc(41);
 292                         strcpy(s, sha1_to_hex(commit->tree->object.sha1));
 293                         v->s = s;
 294                 }
 295                 if (!strcmp(name, "numparent")) {
 296                         char *s = xmalloc(40);
 297                         v->ul = num_parents(commit);
 298                         sprintf(s, "%lu", v->ul);
 299                         v->s = s;
 300                 }
 301                 else if (!strcmp(name, "parent")) {
 302                         int num = num_parents(commit);
 303                         int i;
 304                         struct commit_list *parents;
 305                         char *s = xmalloc(41 * num + 1);
 306                         v->s = s;
 307                         for (i = 0, parents = commit->parents;
 308                              parents;
 309                              parents = parents->next, i = i + 41) {
 310                                 struct commit *parent = parents->item;
 311                                 strcpy(s+i, sha1_to_hex(parent->object.sha1));
 312                                 if (parents->next)
 313                                         s[i+40] = ' ';
 314                         }
 315                         if (!i)
 316                                 *s = '\0';
 317                 }
 318         }
 319 }
 320
 321 static const char *find_wholine(const char *who, int wholen, const char *buf, unsigned long sz)
 322 {
 323         const char *eol;
 324         while (*buf) {
 325                 if (!strncmp(buf, who, wholen) &&
 326                     buf[wholen] == ' ')
 327                         return buf + wholen + 1;
 328                 eol = strchr(buf, '\n');
 329                 if (!eol)
 330                         return "";
 331                 eol++;
 332                 if (*eol == '\n')
 333                         return ""; /* end of header */
 334                 buf = eol;
 335         }
 336         return "";
 337 }
 338
 339 static const char *copy_line(const char *buf)
 340 {
 341         const char *eol = strchrnul(buf, '\n');
 342         return xmemdupz(buf, eol - buf);
 343 }
 344
 345 static const char *copy_name(const char *buf)
 346 {
 347         const char *cp;
 348         for (cp = buf; *cp && *cp != '\n'; cp++) {
 349                 if (!strncmp(cp, " <", 2))
 350                         return xmemdupz(buf, cp - buf);
 351         }
 352         return "";
 353 }
 354
 355 static const char *copy_email(const char *buf)
 356 {
 357         const char *email = strchr(buf, '<');
 358         const char *eoemail;
 359         if (!email)
 360                 return "";
 361         eoemail = strchr(email, '>');
 362         if (!eoemail)
 363                 return "";
 364         return xmemdupz(email, eoemail + 1 - email);
 365 }
 366
 367 static char *copy_subject(const char *buf, unsigned long len)
 368 {
 369         char *r = xmemdupz(buf, len);
 370         int i;
 371
 372         for (i = 0; i < len; i++)
 373                 if (r[i] == '\n')
 374                         r[i] = ' ';
 375
 376         return r;
 377 }
 378
 379 static void grab_date(const char *buf, struct atom_value *v, const char *atomname)
 380 {
 381         const char *eoemail = strstr(buf, "> ");
 382         char *zone;
 383         unsigned long timestamp;
 384         long tz;
 385         enum date_mode date_mode = DATE_NORMAL;
 386         const char *formatp;
 387
 388         /*
 389          * We got here because atomname ends in "date" or "date<something>";
 390          * it's not possible that <something> is not ":<format>" because
 391          * parse_atom() wouldn't have allowed it, so we can assume that no
 392          * ":" means no format is specified, and use the default.
 393          */
 394         formatp = strchr(atomname, ':');
 395         if (formatp != NULL) {
 396                 formatp++;
 397                 date_mode = parse_date_format(formatp);
 398         }
 399
 400         if (!eoemail)
 401                 goto bad;
 402         timestamp = strtoul(eoemail + 2, &zone, 10);
 403         if (timestamp == ULONG_MAX)
 404                 goto bad;
 405         tz = strtol(zone, NULL, 10);
 406         if ((tz == LONG_MIN || tz == LONG_MAX) && errno == ERANGE)
 407                 goto bad;
 408         v->s = xstrdup(show_date(timestamp, tz, date_mode));
 409         v->ul = timestamp;
 410         return;
 411  bad:
 412         v->s = "";
 413         v->ul = 0;
 414 }
 415
 416 /* See grab_values */
 417 static void grab_person(const char *who, struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 418 {
 419         int i;
 420         int wholen = strlen(who);
 421         const char *wholine = NULL;
 422
 423         for (i = 0; i < used_atom_cnt; i++) {
 424                 const char *name = used_atom[i];
 425                 struct atom_value *v = &val[i];
 426                 if (!!deref != (*name == '*'))
 427                         continue;
 428                 if (deref)
 429                         name++;
 430                 if (strncmp(who, name, wholen))
 431                         continue;
 432                 if (name[wholen] != 0 &&
 433                     strcmp(name + wholen, "name") &&
 434                     strcmp(name + wholen, "email") &&
 435                     prefixcmp(name + wholen, "date"))
 436                         continue;
 437                 if (!wholine)
 438                         wholine = find_wholine(who, wholen, buf, sz);
 439                 if (!wholine)
 440                         return; /* no point looking for it */
 441                 if (name[wholen] == 0)
 442                         v->s = copy_line(wholine);
 443                 else if (!strcmp(name + wholen, "name"))
 444                         v->s = copy_name(wholine);
 445                 else if (!strcmp(name + wholen, "email"))
 446                         v->s = copy_email(wholine);
 447                 else if (!prefixcmp(name + wholen, "date"))
 448                         grab_date(wholine, v, name);
 449         }
 450
 451         /*
 452          * For a tag or a commit object, if "creator" or "creatordate" is
 453          * requested, do something special.
 454          */
 455         if (strcmp(who, "tagger") && strcmp(who, "committer"))
 456                 return; /* "author" for commit object is not wanted */
 457         if (!wholine)
 458                 wholine = find_wholine(who, wholen, buf, sz);
 459         if (!wholine)
 460                 return;
 461         for (i = 0; i < used_atom_cnt; i++) {
 462                 const char *name = used_atom[i];
 463                 struct atom_value *v = &val[i];
 464                 if (!!deref != (*name == '*'))
 465                         continue;
 466                 if (deref)
 467                         name++;
 468
 469                 if (!prefixcmp(name, "creatordate"))
 470                         grab_date(wholine, v, name);
 471                 else if (!strcmp(name, "creator"))
 472                         v->s = copy_line(wholine);
 473         }
 474 }
 475
 476 static void find_subpos(const char *buf, unsigned long sz,
 477                         const char **sub, unsigned long *sublen,
 478                         const char **body, unsigned long *bodylen,
 479                         unsigned long *nonsiglen,
 480                         const char **sig, unsigned long *siglen)
 481 {
 482         const char *eol;
 483         /* skip past header until we hit empty line */
 484         while (*buf && *buf != '\n') {
 485                 eol = strchrnul(buf, '\n');
 486                 if (*eol)
 487                         eol++;
 488                 buf = eol;
 489         }
 490         /* skip any empty lines */
 491         while (*buf == '\n')
 492                 buf++;
 493
 494         /* parse signature first; we might not even have a subject line */
 495         *sig = buf + parse_signature(buf, strlen(buf));
 496         *siglen = strlen(*sig);
 497
 498         /* subject is first non-empty line */
 499         *sub = buf;
 500         /* subject goes to first empty line */
 501         while (buf < *sig && *buf && *buf != '\n') {
 502                 eol = strchrnul(buf, '\n');
 503                 if (*eol)
 504                         eol++;
 505                 buf = eol;
 506         }
 507         *sublen = buf - *sub;
 508         /* drop trailing newline, if present */
 509         if (*sublen && (*sub)[*sublen - 1] == '\n')
 510                 *sublen -= 1;
 511
 512         /* skip any empty lines */
 513         while (*buf == '\n')
 514                 buf++;
 515         *body = buf;
 516         *bodylen = strlen(buf);
 517         *nonsiglen = *sig - buf;
 518 }
 519
 520 /* See grab_values */
 521 static void grab_sub_body_contents(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 522 {
 523         int i;
 524         const char *subpos = NULL, *bodypos = NULL, *sigpos = NULL;
 525         unsigned long sublen = 0, bodylen = 0, nonsiglen = 0, siglen = 0;
 526
 527         for (i = 0; i < used_atom_cnt; i++) {
 528                 const char *name = used_atom[i];
 529                 struct atom_value *v = &val[i];
 530                 if (!!deref != (*name == '*'))
 531                         continue;
 532                 if (deref)
 533                         name++;
 534                 if (strcmp(name, "subject") &&
 535                     strcmp(name, "body") &&
 536                     strcmp(name, "contents") &&
 537                     strcmp(name, "contents:subject") &&
 538                     strcmp(name, "contents:body") &&
 539                     strcmp(name, "contents:signature"))
 540                         continue;
 541                 if (!subpos)
 542                         find_subpos(buf, sz,
 543                                     &subpos, &sublen,
 544                                     &bodypos, &bodylen, &nonsiglen,
 545                                     &sigpos, &siglen);
 546
 547                 if (!strcmp(name, "subject"))
 548                         v->s = copy_subject(subpos, sublen);
 549                 else if (!strcmp(name, "contents:subject"))
 550                         v->s = copy_subject(subpos, sublen);
 551                 else if (!strcmp(name, "body"))
 552                         v->s = xmemdupz(bodypos, bodylen);
 553                 else if (!strcmp(name, "contents:body"))
 554                         v->s = xmemdupz(bodypos, nonsiglen);
 555                 else if (!strcmp(name, "contents:signature"))
 556                         v->s = xmemdupz(sigpos, siglen);
 557                 else if (!strcmp(name, "contents"))
 558                         v->s = xstrdup(subpos);
 559         }
 560 }
 561
 562 /*
 563  * We want to have empty print-string for field requests
 564  * that do not apply (e.g. "authordate" for a tag object)
 565  */
 566 static void fill_missing_values(struct atom_value *val)
 567 {
 568         int i;
 569         for (i = 0; i < used_atom_cnt; i++) {
 570                 struct atom_value *v = &val[i];
 571                 if (v->s == NULL)
 572                         v->s = "";
 573         }
 574 }
 575
 576 /*
 577  * val is a list of atom_value to hold returned values.  Extract
 578  * the values for atoms in used_atom array out of (obj, buf, sz).
 579  * when deref is false, (obj, buf, sz) is the object that is
 580  * pointed at by the ref itself; otherwise it is the object the
 581  * ref (which is a tag) refers to.
 582  */
 583 static void grab_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 584 {
 585         grab_common_values(val, deref, obj, buf, sz);
 586         switch (obj->type) {
 587         case OBJ_TAG:
 588                 grab_tag_values(val, deref, obj, buf, sz);
 589                 grab_sub_body_contents(val, deref, obj, buf, sz);
 590                 grab_person("tagger", val, deref, obj, buf, sz);
 591                 break;
 592         case OBJ_COMMIT:
 593                 grab_commit_values(val, deref, obj, buf, sz);
 594                 grab_sub_body_contents(val, deref, obj, buf, sz);
 595                 grab_person("author", val, deref, obj, buf, sz);
 596                 grab_person("committer", val, deref, obj, buf, sz);
 597                 break;
 598         case OBJ_TREE:
 599                 /* grab_tree_values(val, deref, obj, buf, sz); */
 600                 break;
 601         case OBJ_BLOB:
 602                 /* grab_blob_values(val, deref, obj, buf, sz); */
 603                 break;
 604         default:
 605                 die("Eh?  Object of type %d?", obj->type);
 606         }
 607 }
 608
 609 static inline char *copy_advance(char *dst, const char *src)
 610 {
 611         while (*src)
 612                 *dst++ = *src++;
 613         return dst;
 614 }
 615
 616 /*
 617  * Parse the object referred by ref, and grab needed value.
 618  */
 619 static void populate_value(struct refinfo *ref)
 620 {
 621         void *buf;
 622         struct object *obj;
 623         int eaten, i;
 624         unsigned long size;
 625         const unsigned char *tagged;
 626
 627         ref->value = xcalloc(sizeof(struct atom_value), used_atom_cnt);
 628
 629         if (need_symref && (ref->flag & REF_ISSYMREF) && !ref->symref) {
 630                 unsigned char unused1[20];
 631                 const char *symref;
 632                 symref = resolve_ref(ref->refname, unused1, 1, NULL);
 633                 if (symref)
 634                         ref->symref = xstrdup(symref);
 635                 else
 636                         ref->symref = "";
 637         }
 638
 639         /* Fill in specials first */
 640         for (i = 0; i < used_atom_cnt; i++) {
 641                 const char *name = used_atom[i];
 642                 struct atom_value *v = &ref->value[i];
 643                 int deref = 0;
 644                 const char *refname;
 645                 const char *formatp;
 646
 647                 if (*name == '*') {
 648                         deref = 1;
 649                         name++;
 650                 }
 651
 652                 if (!prefixcmp(name, "refname"))
 653                         refname = ref->refname;
 654                 else if (!prefixcmp(name, "symref"))
 655                         refname = ref->symref ? ref->symref : "";
 656                 else if (!prefixcmp(name, "upstream")) {
 657                         struct branch *branch;
 658                         /* only local branches may have an upstream */
 659                         if (prefixcmp(ref->refname, "refs/heads/"))
 660                                 continue;
 661                         branch = branch_get(ref->refname + 11);
 662
 663                         if (!branch || !branch->merge || !branch->merge[0] ||
 664                             !branch->merge[0]->dst)
 665                                 continue;
 666                         refname = branch->merge[0]->dst;
 667                 }
 668                 else if (!strcmp(name, "flag")) {
 669                         char buf[256], *cp = buf;
 670                         if (ref->flag & REF_ISSYMREF)
 671                                 cp = copy_advance(cp, ",symref");
 672                         if (ref->flag & REF_ISPACKED)
 673                                 cp = copy_advance(cp, ",packed");
 674                         if (cp == buf)
 675                                 v->s = "";
 676                         else {
 677                                 *cp = '\0';
 678                                 v->s = xstrdup(buf + 1);
 679                         }
 680                         continue;
 681                 }
 682                 else
 683                         continue;
 684
 685                 formatp = strchr(name, ':');
 686                 /* look for "short" refname format */
 687                 if (formatp) {
 688                         formatp++;
 689                         if (!strcmp(formatp, "short"))
 690                                 refname = shorten_unambiguous_ref(refname,
 691                                                       warn_ambiguous_refs);
 692                         else
 693                                 die("unknown %.*s format %s",
 694                                     (int)(formatp - name), name, formatp);
 695                 }
 696
 697                 if (!deref)
 698                         v->s = refname;
 699                 else {
 700                         int len = strlen(refname);
 701                         char *s = xmalloc(len + 4);
 702                         sprintf(s, "%s^{}", refname);
 703                         v->s = s;
 704                 }
 705         }
 706
 707         for (i = 0; i < used_atom_cnt; i++) {
 708                 struct atom_value *v = &ref->value[i];
 709                 if (v->s == NULL)
 710                         goto need_obj;
 711         }
 712         return;
 713
 714  need_obj:
 715         buf = get_obj(ref->objectname, &obj, &size, &eaten);
 716         if (!buf)
 717                 die("missing object %s for %s",
 718                     sha1_to_hex(ref->objectname), ref->refname);
 719         if (!obj)
 720                 die("parse_object_buffer failed on %s for %s",
 721                     sha1_to_hex(ref->objectname), ref->refname);
 722
 723         grab_values(ref->value, 0, obj, buf, size);
 724         if (!eaten)
 725                 free(buf);
 726
 727         /*
 728          * If there is no atom that wants to know about tagged
 729          * object, we are done.
 730          */
 731         if (!need_tagged || (obj->type != OBJ_TAG))
 732                 return;
 733
 734         /*
 735          * If it is a tag object, see if we use a value that derefs
 736          * the object, and if we do grab the object it refers to.
 737          */
 738         tagged = ((struct tag *)obj)->tagged->sha1;
 739
 740         /*
 741          * NEEDSWORK: This derefs tag only once, which
 742          * is good to deal with chains of trust, but
 743          * is not consistent with what deref_tag() does
 744          * which peels the onion to the core.
 745          */
 746         buf = get_obj(tagged, &obj, &size, &eaten);
 747         if (!buf)
 748                 die("missing object %s for %s",
 749                     sha1_to_hex(tagged), ref->refname);
 750         if (!obj)
 751                 die("parse_object_buffer failed on %s for %s",
 752                     sha1_to_hex(tagged), ref->refname);
 753         grab_values(ref->value, 1, obj, buf, size);
 754         if (!eaten)
 755                 free(buf);
 756 }
 757
 758 /*
 759  * Given a ref, return the value for the atom.  This lazily gets value
 760  * out of the object by calling populate value.
 761  */
 762 static void get_value(struct refinfo *ref, int atom, struct atom_value **v)
 763 {
 764         if (!ref->value) {
 765                 populate_value(ref);
 766                 fill_missing_values(ref->value);
 767         }
 768         *v = &ref->value[atom];
 769 }
 770
 771 struct grab_ref_cbdata {
 772         struct refinfo **grab_array;
 773         const char **grab_pattern;
 774         int grab_cnt;
 775 };
 776
 777 /*
 778  * A call-back given to for_each_ref().  Filter refs and keep them for
 779  * later object processing.
 780  */
 781 static int grab_single_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 782 {
 783         struct grab_ref_cbdata *cb = cb_data;
 784         struct refinfo *ref;
 785         int cnt;
 786
 787         if (*cb->grab_pattern) {
 788                 const char **pattern;
 789                 int namelen = strlen(refname);
 790                 for (pattern = cb->grab_pattern; *pattern; pattern++) {
 791                         const char *p = *pattern;
 792                         int plen = strlen(p);
 793
 794                         if ((plen <= namelen) &&
 795                             !strncmp(refname, p, plen) &&
 796                             (refname[plen] == '\0' ||
 797                              refname[plen] == '/' ||
 798                              p[plen-1] == '/'))
 799                                 break;
 800                         if (!fnmatch(p, refname, FNM_PATHNAME))
 801                                 break;
 802                 }
 803                 if (!*pattern)
 804                         return 0;
 805         }
 806
 807         /*
 808          * We do not open the object yet; sort may only need refname
 809          * to do its job and the resulting list may yet to be pruned
 810          * by maxcount logic.
 811          */
 812         ref = xcalloc(1, sizeof(*ref));
 813         ref->refname = xstrdup(refname);
 814         hashcpy(ref->objectname, sha1);
 815         ref->flag = flag;
 816
 817         cnt = cb->grab_cnt;
 818         cb->grab_array = xrealloc(cb->grab_array,
 819                                   sizeof(*cb->grab_array) * (cnt + 1));
 820         cb->grab_array[cnt++] = ref;
 821         cb->grab_cnt = cnt;
 822         return 0;
 823 }
 824
 825 static int cmp_ref_sort(struct ref_sort *s, struct refinfo *a, struct refinfo *b)
 826 {
 827         struct atom_value *va, *vb;
 828         int cmp;
 829         cmp_type cmp_type = used_atom_type[s->atom];
 830
 831         get_value(a, s->atom, &va);
 832         get_value(b, s->atom, &vb);
 833         switch (cmp_type) {
 834         case FIELD_STR:
 835                 cmp = strcmp(va->s, vb->s);
 836                 break;
 837         default:
 838                 if (va->ul < vb->ul)
 839                         cmp = -1;
 840                 else if (va->ul == vb->ul)
 841                         cmp = 0;
 842                 else
 843                         cmp = 1;
 844                 break;
 845         }
 846         return (s->reverse) ? -cmp : cmp;
 847 }
 848
 849 static struct ref_sort *ref_sort;
 850 static int compare_refs(const void *a_, const void *b_)
 851 {
 852         struct refinfo *a = *((struct refinfo **)a_);
 853         struct refinfo *b = *((struct refinfo **)b_);
 854         struct ref_sort *s;
 855
 856         for (s = ref_sort; s; s = s->next) {
 857                 int cmp = cmp_ref_sort(s, a, b);
 858                 if (cmp)
 859                         return cmp;
 860         }
 861         return 0;
 862 }
 863
 864 static void sort_refs(struct ref_sort *sort, struct refinfo **refs, int num_refs)
 865 {
 866         ref_sort = sort;
 867         qsort(refs, num_refs, sizeof(struct refinfo *), compare_refs);
 868 }
 869
 870 static void print_value(struct refinfo *ref, int atom, int quote_style)
 871 {
 872         struct atom_value *v;
 873         get_value(ref, atom, &v);
 874         switch (quote_style) {
 875         case QUOTE_NONE:
 876                 fputs(v->s, stdout);
 877                 break;
 878         case QUOTE_SHELL:
 879                 sq_quote_print(stdout, v->s);
 880                 break;
 881         case QUOTE_PERL:
 882                 perl_quote_print(stdout, v->s);
 883                 break;
 884         case QUOTE_PYTHON:
 885                 python_quote_print(stdout, v->s);
 886                 break;
 887         case QUOTE_TCL:
 888                 tcl_quote_print(stdout, v->s);
 889                 break;
 890         }
 891 }
 892
 893 static int hex1(char ch)
 894 {
 895         if ('0' <= ch && ch <= '9')
 896                 return ch - '0';
 897         else if ('a' <= ch && ch <= 'f')
 898                 return ch - 'a' + 10;
 899         else if ('A' <= ch && ch <= 'F')
 900                 return ch - 'A' + 10;
 901         return -1;
 902 }
 903 static int hex2(const char *cp)
 904 {
 905         if (cp[0] && cp[1])
 906                 return (hex1(cp[0]) << 4) | hex1(cp[1]);
 907         else
 908                 return -1;
 909 }
 910
 911 static void emit(const char *cp, const char *ep)
 912 {
 913         while (*cp && (!ep || cp < ep)) {
 914                 if (*cp == '%') {
 915                         if (cp[1] == '%')
 916                                 cp++;
 917                         else {
 918                                 int ch = hex2(cp + 1);
 919                                 if (0 <= ch) {
 920                                         putchar(ch);
 921                                         cp += 3;
 922                                         continue;
 923                                 }
 924                         }
 925                 }
 926                 putchar(*cp);
 927                 cp++;
 928         }
 929 }
 930
 931 static void show_ref(struct refinfo *info, const char *format, int quote_style)
 932 {
 933         const char *cp, *sp, *ep;
 934
 935         for (cp = format; *cp && (sp = find_next(cp)); cp = ep + 1) {
 936                 ep = strchr(sp, ')');
 937                 if (cp < sp)
 938                         emit(cp, sp);
 939                 print_value(info, parse_atom(sp + 2, ep), quote_style);
 940         }
 941         if (*cp) {
 942                 sp = cp + strlen(cp);
 943                 emit(cp, sp);
 944         }
 945         putchar('\n');
 946 }
 947
 948 static struct ref_sort *default_sort(void)
 949 {
 950         static const char cstr_name[] = "refname";
 951
 952         struct ref_sort *sort = xcalloc(1, sizeof(*sort));
 953
 954         sort->next = NULL;
 955         sort->atom = parse_atom(cstr_name, cstr_name + strlen(cstr_name));
 956         return sort;
 957 }
 958
 959 static int opt_parse_sort(const struct option *opt, const char *arg, int unset)
 960 {
 961         struct ref_sort **sort_tail = opt->value;
 962         struct ref_sort *s;
 963         int len;
 964
 965         if (!arg) /* should --no-sort void the list ? */
 966                 return -1;
 967
 968         *sort_tail = s = xcalloc(1, sizeof(*s));
 969
 970         if (*arg == '-') {
 971                 s->reverse = 1;
 972                 arg++;
 973         }
 974         len = strlen(arg);
 975         s->atom = parse_atom(arg, arg+len);
 976         return 0;
 977 }
 978
 979 static char const * const for_each_ref_usage[] = {
 980         "git for-each-ref [options] [<pattern>]",
 981         NULL
 982 };
 983
 984 int cmd_for_each_ref(int argc, const char **argv, const char *prefix)
 985 {
 986         int i, num_refs;
 987         const char *format = "%(objectname) %(objecttype)\t%(refname)";
 988         struct ref_sort *sort = NULL, **sort_tail = &sort;
 989         int maxcount = 0, quote_style = 0;
 990         struct refinfo **refs;
 991         struct grab_ref_cbdata cbdata;
 992
 993         struct option opts[] = {
 994                 OPT_BIT('s', "shell", &quote_style,
 995                         "quote placeholders suitably for shells", QUOTE_SHELL),
 996                 OPT_BIT('p', "perl",  &quote_style,
 997                         "quote placeholders suitably for perl", QUOTE_PERL),
 998                 OPT_BIT(0 , "python", &quote_style,
 999                         "quote placeholders suitably for python", QUOTE_PYTHON),
1000                 OPT_BIT(0 , "tcl",  &quote_style,
1001                         "quote placeholders suitably for tcl", QUOTE_TCL),
1002
1003                 OPT_GROUP(""),
1004                 OPT_INTEGER( 0 , "count", &maxcount, "show only <n> matched refs"),
1005                 OPT_STRING(  0 , "format", &format, "format", "format to use for the output"),
1006                 OPT_CALLBACK(0 , "sort", sort_tail, "key",
1007                             "field name to sort on", &opt_parse_sort),
1008                 OPT_END(),
1009         };
1010
1011         parse_options(argc, argv, prefix, opts, for_each_ref_usage, 0);
1012         if (maxcount < 0) {
1013                 error("invalid --count argument: `%d'", maxcount);
1014                 usage_with_options(for_each_ref_usage, opts);
1015         }
1016         if (HAS_MULTI_BITS(quote_style)) {
1017                 error("more than one quoting style?");
1018                 usage_with_options(for_each_ref_usage, opts);
1019         }
1020         if (verify_format(format))
1021                 usage_with_options(for_each_ref_usage, opts);
1022
1023         if (!sort)
1024                 sort = default_sort();
1025         sort_atom_limit = used_atom_cnt;
1026
1027         /* for warn_ambiguous_refs */
1028         git_config(git_default_config, NULL);
1029
1030         memset(&cbdata, 0, sizeof(cbdata));
1031         cbdata.grab_pattern = argv;
1032         for_each_rawref(grab_single_ref, &cbdata);
1033         refs = cbdata.grab_array;
1034         num_refs = cbdata.grab_cnt;
1035
1036         sort_refs(sort, refs, num_refs);
1037
1038         if (!maxcount || num_refs < maxcount)
1039                 maxcount = num_refs;
1040         for (i = 0; i < maxcount; i++)
1041                 show_ref(refs[i], format, quote_style);
1042         return 0;
1043 }