01b5c18ef084c1548822f41c14abfb36383a5e1b
   1#include "builtin.h"
   2#include "cache.h"
   3#include "parse-options.h"
   4#include "refs.h"
   5#include "wildmatch.h"
   6#include "commit.h"
   7#include "remote.h"
   8#include "color.h"
   9#include "tag.h"
  10#include "quote.h"
  11#include "ref-filter.h"
  12#include "revision.h"
  13#include "utf8.h"
  14#include "git-compat-util.h"
  15#include "version.h"
  16#include "trailer.h"
  17#include "wt-status.h"
  18
  19static struct ref_msg {
  20        const char *gone;
  21        const char *ahead;
  22        const char *behind;
  23        const char *ahead_behind;
  24} msgs = {
  25         /* Untranslated plumbing messages: */
  26        "gone",
  27        "ahead %d",
  28        "behind %d",
  29        "ahead %d, behind %d"
  30};
  31
  32void setup_ref_filter_porcelain_msg(void)
  33{
  34        msgs.gone = _("gone");
  35        msgs.ahead = _("ahead %d");
  36        msgs.behind = _("behind %d");
  37        msgs.ahead_behind = _("ahead %d, behind %d");
  38}
  39
  40typedef enum { FIELD_STR, FIELD_ULONG, FIELD_TIME } cmp_type;
  41typedef enum { COMPARE_EQUAL, COMPARE_UNEQUAL, COMPARE_NONE } cmp_status;
  42
  43struct align {
  44        align_type position;
  45        unsigned int width;
  46};
  47
  48struct if_then_else {
  49        cmp_status cmp_status;
  50        const char *str;
  51        unsigned int then_atom_seen : 1,
  52                else_atom_seen : 1,
  53                condition_satisfied : 1;
  54};
  55
  56struct refname_atom {
  57        enum { R_NORMAL, R_SHORT, R_LSTRIP, R_RSTRIP } option;
  58        int lstrip, rstrip;
  59};
  60
  61/*
  62 * An atom is a valid field atom listed below, possibly prefixed with
  63 * a "*" to denote deref_tag().
  64 *
  65 * We parse given format string and sort specifiers, and make a list
  66 * of properties that we need to extract out of objects.  ref_array_item
  67 * structure will hold an array of values extracted that can be
  68 * indexed with the "atom number", which is an index into this
  69 * array.
  70 */
  71static struct used_atom {
  72        const char *name;
  73        cmp_type type;
  74        union {
  75                char color[COLOR_MAXLEN];
  76                struct align align;
  77                struct {
  78                        enum { RR_REF, RR_TRACK, RR_TRACKSHORT } option;
  79                        struct refname_atom refname;
  80                        unsigned int nobracket : 1;
  81                } remote_ref;
  82                struct {
  83                        enum { C_BARE, C_BODY, C_BODY_DEP, C_LINES, C_SIG, C_SUB, C_TRAILERS } option;
  84                        unsigned int nlines;
  85                } contents;
  86                struct {
  87                        cmp_status cmp_status;
  88                        const char *str;
  89                } if_then_else;
  90                struct {
  91                        enum { O_FULL, O_LENGTH, O_SHORT } option;
  92                        unsigned int length;
  93                } objectname;
  94                struct refname_atom refname;
  95        } u;
  96} *used_atom;
  97static int used_atom_cnt, need_tagged, need_symref;
  98static int need_color_reset_at_eol;
  99
 100static void color_atom_parser(struct used_atom *atom, const char *color_value)
 101{
 102        if (!color_value)
 103                die(_("expected format: %%(color:<color>)"));
 104        if (color_parse(color_value, atom->u.color) < 0)
 105                die(_("unrecognized color: %%(color:%s)"), color_value);
 106}
 107
 108static void refname_atom_parser_internal(struct refname_atom *atom,
 109                                         const char *arg, const char *name)
 110{
 111        if (!arg)
 112                atom->option = R_NORMAL;
 113        else if (!strcmp(arg, "short"))
 114                atom->option = R_SHORT;
 115        else if (skip_prefix(arg, "lstrip=", &arg)) {
 116                atom->option = R_LSTRIP;
 117                if (strtol_i(arg, 10, &atom->lstrip))
 118                        die(_("Integer value expected refname:lstrip=%s"), arg);
 119        } else if (skip_prefix(arg, "rstrip=", &arg)) {
 120                atom->option = R_RSTRIP;
 121                if (strtol_i(arg, 10, &atom->rstrip))
 122                        die(_("Integer value expected refname:rstrip=%s"), arg);
 123        } else
 124                die(_("unrecognized %%(%s) argument: %s"), name, arg);
 125}
 126
 127static void remote_ref_atom_parser(struct used_atom *atom, const char *arg)
 128{
 129        struct string_list params = STRING_LIST_INIT_DUP;
 130        int i;
 131
 132        if (!arg) {
 133                atom->u.remote_ref.option = RR_REF;
 134                refname_atom_parser_internal(&atom->u.remote_ref.refname,
 135                                             arg, atom->name);
 136                return;
 137        }
 138
 139        atom->u.remote_ref.nobracket = 0;
 140        string_list_split(&params, arg, ',', -1);
 141
 142        for (i = 0; i < params.nr; i++) {
 143                const char *s = params.items[i].string;
 144
 145                if (!strcmp(s, "track"))
 146                        atom->u.remote_ref.option = RR_TRACK;
 147                else if (!strcmp(s, "trackshort"))
 148                        atom->u.remote_ref.option = RR_TRACKSHORT;
 149                else if (!strcmp(s, "nobracket"))
 150                        atom->u.remote_ref.nobracket = 1;
 151                else {
 152                        atom->u.remote_ref.option = RR_REF;
 153                        refname_atom_parser_internal(&atom->u.remote_ref.refname,
 154                                                     arg, atom->name);
 155                }
 156        }
 157
 158        string_list_clear(&params, 0);
 159}
 160
 161static void body_atom_parser(struct used_atom *atom, const char *arg)
 162{
 163        if (arg)
 164                die(_("%%(body) does not take arguments"));
 165        atom->u.contents.option = C_BODY_DEP;
 166}
 167
 168static void subject_atom_parser(struct used_atom *atom, const char *arg)
 169{
 170        if (arg)
 171                die(_("%%(subject) does not take arguments"));
 172        atom->u.contents.option = C_SUB;
 173}
 174
 175static void trailers_atom_parser(struct used_atom *atom, const char *arg)
 176{
 177        if (arg)
 178                die(_("%%(trailers) does not take arguments"));
 179        atom->u.contents.option = C_TRAILERS;
 180}
 181
 182static void contents_atom_parser(struct used_atom *atom, const char *arg)
 183{
 184        if (!arg)
 185                atom->u.contents.option = C_BARE;
 186        else if (!strcmp(arg, "body"))
 187                atom->u.contents.option = C_BODY;
 188        else if (!strcmp(arg, "signature"))
 189                atom->u.contents.option = C_SIG;
 190        else if (!strcmp(arg, "subject"))
 191                atom->u.contents.option = C_SUB;
 192        else if (!strcmp(arg, "trailers"))
 193                atom->u.contents.option = C_TRAILERS;
 194        else if (skip_prefix(arg, "lines=", &arg)) {
 195                atom->u.contents.option = C_LINES;
 196                if (strtoul_ui(arg, 10, &atom->u.contents.nlines))
 197                        die(_("positive value expected contents:lines=%s"), arg);
 198        } else
 199                die(_("unrecognized %%(contents) argument: %s"), arg);
 200}
 201
 202static void objectname_atom_parser(struct used_atom *atom, const char *arg)
 203{
 204        if (!arg)
 205                atom->u.objectname.option = O_FULL;
 206        else if (!strcmp(arg, "short"))
 207                atom->u.objectname.option = O_SHORT;
 208        else if (skip_prefix(arg, "short=", &arg)) {
 209                atom->u.objectname.option = O_LENGTH;
 210                if (strtoul_ui(arg, 10, &atom->u.objectname.length) ||
 211                    atom->u.objectname.length == 0)
 212                        die(_("positive value expected objectname:short=%s"), arg);
 213                if (atom->u.objectname.length < MINIMUM_ABBREV)
 214                        atom->u.objectname.length = MINIMUM_ABBREV;
 215        } else
 216                die(_("unrecognized %%(objectname) argument: %s"), arg);
 217}
 218
 219static void refname_atom_parser(struct used_atom *atom, const char *arg)
 220{
 221        return refname_atom_parser_internal(&atom->u.refname, arg, atom->name);
 222}
 223
 224static align_type parse_align_position(const char *s)
 225{
 226        if (!strcmp(s, "right"))
 227                return ALIGN_RIGHT;
 228        else if (!strcmp(s, "middle"))
 229                return ALIGN_MIDDLE;
 230        else if (!strcmp(s, "left"))
 231                return ALIGN_LEFT;
 232        return -1;
 233}
 234
 235static void align_atom_parser(struct used_atom *atom, const char *arg)
 236{
 237        struct align *align = &atom->u.align;
 238        struct string_list params = STRING_LIST_INIT_DUP;
 239        int i;
 240        unsigned int width = ~0U;
 241
 242        if (!arg)
 243                die(_("expected format: %%(align:<width>,<position>)"));
 244
 245        align->position = ALIGN_LEFT;
 246
 247        string_list_split(&params, arg, ',', -1);
 248        for (i = 0; i < params.nr; i++) {
 249                const char *s = params.items[i].string;
 250                int position;
 251
 252                if (skip_prefix(s, "position=", &s)) {
 253                        position = parse_align_position(s);
 254                        if (position < 0)
 255                                die(_("unrecognized position:%s"), s);
 256                        align->position = position;
 257                } else if (skip_prefix(s, "width=", &s)) {
 258                        if (strtoul_ui(s, 10, &width))
 259                                die(_("unrecognized width:%s"), s);
 260                } else if (!strtoul_ui(s, 10, &width))
 261                        ;
 262                else if ((position = parse_align_position(s)) >= 0)
 263                        align->position = position;
 264                else
 265                        die(_("unrecognized %%(align) argument: %s"), s);
 266        }
 267
 268        if (width == ~0U)
 269                die(_("positive width expected with the %%(align) atom"));
 270        align->width = width;
 271        string_list_clear(&params, 0);
 272}
 273
 274static void if_atom_parser(struct used_atom *atom, const char *arg)
 275{
 276        if (!arg) {
 277                atom->u.if_then_else.cmp_status = COMPARE_NONE;
 278                return;
 279        } else if (skip_prefix(arg, "equals=", &atom->u.if_then_else.str)) {
 280                atom->u.if_then_else.cmp_status = COMPARE_EQUAL;
 281        } else if (skip_prefix(arg, "notequals=", &atom->u.if_then_else.str)) {
 282                atom->u.if_then_else.cmp_status = COMPARE_UNEQUAL;
 283        } else {
 284                die(_("unrecognized %%(if) argument: %s"), arg);
 285        }
 286}
 287
 288
 289static struct {
 290        const char *name;
 291        cmp_type cmp_type;
 292        void (*parser)(struct used_atom *atom, const char *arg);
 293} valid_atom[] = {
 294        { "refname" , FIELD_STR, refname_atom_parser },
 295        { "objecttype" },
 296        { "objectsize", FIELD_ULONG },
 297        { "objectname", FIELD_STR, objectname_atom_parser },
 298        { "tree" },
 299        { "parent" },
 300        { "numparent", FIELD_ULONG },
 301        { "object" },
 302        { "type" },
 303        { "tag" },
 304        { "author" },
 305        { "authorname" },
 306        { "authoremail" },
 307        { "authordate", FIELD_TIME },
 308        { "committer" },
 309        { "committername" },
 310        { "committeremail" },
 311        { "committerdate", FIELD_TIME },
 312        { "tagger" },
 313        { "taggername" },
 314        { "taggeremail" },
 315        { "taggerdate", FIELD_TIME },
 316        { "creator" },
 317        { "creatordate", FIELD_TIME },
 318        { "subject", FIELD_STR, subject_atom_parser },
 319        { "body", FIELD_STR, body_atom_parser },
 320        { "trailers", FIELD_STR, trailers_atom_parser },
 321        { "contents", FIELD_STR, contents_atom_parser },
 322        { "upstream", FIELD_STR, remote_ref_atom_parser },
 323        { "push", FIELD_STR, remote_ref_atom_parser },
 324        { "symref", FIELD_STR, refname_atom_parser },
 325        { "flag" },
 326        { "HEAD" },
 327        { "color", FIELD_STR, color_atom_parser },
 328        { "align", FIELD_STR, align_atom_parser },
 329        { "end" },
 330        { "if", FIELD_STR, if_atom_parser },
 331        { "then" },
 332        { "else" },
 333};
 334
 335#define REF_FORMATTING_STATE_INIT  { 0, NULL }
 336
 337struct ref_formatting_stack {
 338        struct ref_formatting_stack *prev;
 339        struct strbuf output;
 340        void (*at_end)(struct ref_formatting_stack **stack);
 341        void *at_end_data;
 342};
 343
 344struct ref_formatting_state {
 345        int quote_style;
 346        struct ref_formatting_stack *stack;
 347};
 348
 349struct atom_value {
 350        const char *s;
 351        void (*handler)(struct atom_value *atomv, struct ref_formatting_state *state);
 352        unsigned long ul; /* used for sorting when not FIELD_STR */
 353        struct used_atom *atom;
 354};
 355
 356/*
 357 * Used to parse format string and sort specifiers
 358 */
 359int parse_ref_filter_atom(const char *atom, const char *ep)
 360{
 361        const char *sp;
 362        const char *arg;
 363        int i, at, atom_len;
 364
 365        sp = atom;
 366        if (*sp == '*' && sp < ep)
 367                sp++; /* deref */
 368        if (ep <= sp)
 369                die(_("malformed field name: %.*s"), (int)(ep-atom), atom);
 370
 371        /* Do we have the atom already used elsewhere? */
 372        for (i = 0; i < used_atom_cnt; i++) {
 373                int len = strlen(used_atom[i].name);
 374                if (len == ep - atom && !memcmp(used_atom[i].name, atom, len))
 375                        return i;
 376        }
 377
 378        /*
 379         * If the atom name has a colon, strip it and everything after
 380         * it off - it specifies the format for this entry, and
 381         * shouldn't be used for checking against the valid_atom
 382         * table.
 383         */
 384        arg = memchr(sp, ':', ep - sp);
 385        atom_len = (arg ? arg : ep) - sp;
 386
 387        /* Is the atom a valid one? */
 388        for (i = 0; i < ARRAY_SIZE(valid_atom); i++) {
 389                int len = strlen(valid_atom[i].name);
 390                if (len == atom_len && !memcmp(valid_atom[i].name, sp, len))
 391                        break;
 392        }
 393
 394        if (ARRAY_SIZE(valid_atom) <= i)
 395                die(_("unknown field name: %.*s"), (int)(ep-atom), atom);
 396
 397        /* Add it in, including the deref prefix */
 398        at = used_atom_cnt;
 399        used_atom_cnt++;
 400        REALLOC_ARRAY(used_atom, used_atom_cnt);
 401        used_atom[at].name = xmemdupz(atom, ep - atom);
 402        used_atom[at].type = valid_atom[i].cmp_type;
 403        if (arg)
 404                arg = used_atom[at].name + (arg - atom) + 1;
 405        memset(&used_atom[at].u, 0, sizeof(used_atom[at].u));
 406        if (valid_atom[i].parser)
 407                valid_atom[i].parser(&used_atom[at], arg);
 408        if (*atom == '*')
 409                need_tagged = 1;
 410        if (!strcmp(valid_atom[i].name, "symref"))
 411                need_symref = 1;
 412        return at;
 413}
 414
 415static void quote_formatting(struct strbuf *s, const char *str, int quote_style)
 416{
 417        switch (quote_style) {
 418        case QUOTE_NONE:
 419                strbuf_addstr(s, str);
 420                break;
 421        case QUOTE_SHELL:
 422                sq_quote_buf(s, str);
 423                break;
 424        case QUOTE_PERL:
 425                perl_quote_buf(s, str);
 426                break;
 427        case QUOTE_PYTHON:
 428                python_quote_buf(s, str);
 429                break;
 430        case QUOTE_TCL:
 431                tcl_quote_buf(s, str);
 432                break;
 433        }
 434}
 435
 436static void append_atom(struct atom_value *v, struct ref_formatting_state *state)
 437{
 438        /*
 439         * Quote formatting is only done when the stack has a single
 440         * element. Otherwise quote formatting is done on the
 441         * element's entire output strbuf when the %(end) atom is
 442         * encountered.
 443         */
 444        if (!state->stack->prev)
 445                quote_formatting(&state->stack->output, v->s, state->quote_style);
 446        else
 447                strbuf_addstr(&state->stack->output, v->s);
 448}
 449
 450static void push_stack_element(struct ref_formatting_stack **stack)
 451{
 452        struct ref_formatting_stack *s = xcalloc(1, sizeof(struct ref_formatting_stack));
 453
 454        strbuf_init(&s->output, 0);
 455        s->prev = *stack;
 456        *stack = s;
 457}
 458
 459static void pop_stack_element(struct ref_formatting_stack **stack)
 460{
 461        struct ref_formatting_stack *current = *stack;
 462        struct ref_formatting_stack *prev = current->prev;
 463
 464        if (prev)
 465                strbuf_addbuf(&prev->output, &current->output);
 466        strbuf_release(&current->output);
 467        free(current);
 468        *stack = prev;
 469}
 470
 471static void end_align_handler(struct ref_formatting_stack **stack)
 472{
 473        struct ref_formatting_stack *cur = *stack;
 474        struct align *align = (struct align *)cur->at_end_data;
 475        struct strbuf s = STRBUF_INIT;
 476
 477        strbuf_utf8_align(&s, align->position, align->width, cur->output.buf);
 478        strbuf_swap(&cur->output, &s);
 479        strbuf_release(&s);
 480}
 481
 482static void align_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
 483{
 484        struct ref_formatting_stack *new;
 485
 486        push_stack_element(&state->stack);
 487        new = state->stack;
 488        new->at_end = end_align_handler;
 489        new->at_end_data = &atomv->atom->u.align;
 490}
 491
 492static void if_then_else_handler(struct ref_formatting_stack **stack)
 493{
 494        struct ref_formatting_stack *cur = *stack;
 495        struct ref_formatting_stack *prev = cur->prev;
 496        struct if_then_else *if_then_else = (struct if_then_else *)cur->at_end_data;
 497
 498        if (!if_then_else->then_atom_seen)
 499                die(_("format: %%(if) atom used without a %%(then) atom"));
 500
 501        if (if_then_else->else_atom_seen) {
 502                /*
 503                 * There is an %(else) atom: we need to drop one state from the
 504                 * stack, either the %(else) branch if the condition is satisfied, or
 505                 * the %(then) branch if it isn't.
 506                 */
 507                if (if_then_else->condition_satisfied) {
 508                        strbuf_reset(&cur->output);
 509                        pop_stack_element(&cur);
 510                } else {
 511                        strbuf_swap(&cur->output, &prev->output);
 512                        strbuf_reset(&cur->output);
 513                        pop_stack_element(&cur);
 514                }
 515        } else if (!if_then_else->condition_satisfied) {
 516                /*
 517                 * No %(else) atom: just drop the %(then) branch if the
 518                 * condition is not satisfied.
 519                 */
 520                strbuf_reset(&cur->output);
 521        }
 522
 523        *stack = cur;
 524        free(if_then_else);
 525}
 526
 527static void if_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
 528{
 529        struct ref_formatting_stack *new;
 530        struct if_then_else *if_then_else = xcalloc(sizeof(struct if_then_else), 1);
 531
 532        if_then_else->str = atomv->atom->u.if_then_else.str;
 533        if_then_else->cmp_status = atomv->atom->u.if_then_else.cmp_status;
 534
 535        push_stack_element(&state->stack);
 536        new = state->stack;
 537        new->at_end = if_then_else_handler;
 538        new->at_end_data = if_then_else;
 539}
 540
 541static int is_empty(const char *s)
 542{
 543        while (*s != '\0') {
 544                if (!isspace(*s))
 545                        return 0;
 546                s++;
 547        }
 548        return 1;
 549}
 550
 551static void then_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
 552{
 553        struct ref_formatting_stack *cur = state->stack;
 554        struct if_then_else *if_then_else = NULL;
 555
 556        if (cur->at_end == if_then_else_handler)
 557                if_then_else = (struct if_then_else *)cur->at_end_data;
 558        if (!if_then_else)
 559                die(_("format: %%(then) atom used without an %%(if) atom"));
 560        if (if_then_else->then_atom_seen)
 561                die(_("format: %%(then) atom used more than once"));
 562        if (if_then_else->else_atom_seen)
 563                die(_("format: %%(then) atom used after %%(else)"));
 564        if_then_else->then_atom_seen = 1;
 565        /*
 566         * If the 'equals' or 'notequals' attribute is used then
 567         * perform the required comparison. If not, only non-empty
 568         * strings satisfy the 'if' condition.
 569         */
 570        if (if_then_else->cmp_status == COMPARE_EQUAL) {
 571                if (!strcmp(if_then_else->str, cur->output.buf))
 572                        if_then_else->condition_satisfied = 1;
 573        } else if (if_then_else->cmp_status == COMPARE_UNEQUAL) {
 574                if (strcmp(if_then_else->str, cur->output.buf))
 575                        if_then_else->condition_satisfied = 1;
 576        } else if (cur->output.len && !is_empty(cur->output.buf))
 577                if_then_else->condition_satisfied = 1;
 578        strbuf_reset(&cur->output);
 579}
 580
 581static void else_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
 582{
 583        struct ref_formatting_stack *prev = state->stack;
 584        struct if_then_else *if_then_else = NULL;
 585
 586        if (prev->at_end == if_then_else_handler)
 587                if_then_else = (struct if_then_else *)prev->at_end_data;
 588        if (!if_then_else)
 589                die(_("format: %%(else) atom used without an %%(if) atom"));
 590        if (!if_then_else->then_atom_seen)
 591                die(_("format: %%(else) atom used without a %%(then) atom"));
 592        if (if_then_else->else_atom_seen)
 593                die(_("format: %%(else) atom used more than once"));
 594        if_then_else->else_atom_seen = 1;
 595        push_stack_element(&state->stack);
 596        state->stack->at_end_data = prev->at_end_data;
 597        state->stack->at_end = prev->at_end;
 598}
 599
 600static void end_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
 601{
 602        struct ref_formatting_stack *current = state->stack;
 603        struct strbuf s = STRBUF_INIT;
 604
 605        if (!current->at_end)
 606                die(_("format: %%(end) atom used without corresponding atom"));
 607        current->at_end(&state->stack);
 608
 609        /*  Stack may have been popped within at_end(), hence reset the current pointer */
 610        current = state->stack;
 611
 612        /*
 613         * Perform quote formatting when the stack element is that of
 614         * a supporting atom. If nested then perform quote formatting
 615         * only on the topmost supporting atom.
 616         */
 617        if (!current->prev->prev) {
 618                quote_formatting(&s, current->output.buf, state->quote_style);
 619                strbuf_swap(&current->output, &s);
 620        }
 621        strbuf_release(&s);
 622        pop_stack_element(&state->stack);
 623}
 624
 625/*
 626 * In a format string, find the next occurrence of %(atom).
 627 */
 628static const char *find_next(const char *cp)
 629{
 630        while (*cp) {
 631                if (*cp == '%') {
 632                        /*
 633                         * %( is the start of an atom;
 634                         * %% is a quoted per-cent.
 635                         */
 636                        if (cp[1] == '(')
 637                                return cp;
 638                        else if (cp[1] == '%')
 639                                cp++; /* skip over two % */
 640                        /* otherwise this is a singleton, literal % */
 641                }
 642                cp++;
 643        }
 644        return NULL;
 645}
 646
 647/*
 648 * Make sure the format string is well formed, and parse out
 649 * the used atoms.
 650 */
 651int verify_ref_format(const char *format)
 652{
 653        const char *cp, *sp;
 654
 655        need_color_reset_at_eol = 0;
 656        for (cp = format; *cp && (sp = find_next(cp)); ) {
 657                const char *color, *ep = strchr(sp, ')');
 658                int at;
 659
 660                if (!ep)
 661                        return error(_("malformed format string %s"), sp);
 662                /* sp points at "%(" and ep points at the closing ")" */
 663                at = parse_ref_filter_atom(sp + 2, ep);
 664                cp = ep + 1;
 665
 666                if (skip_prefix(used_atom[at].name, "color:", &color))
 667                        need_color_reset_at_eol = !!strcmp(color, "reset");
 668        }
 669        return 0;
 670}
 671
 672/*
 673 * Given an object name, read the object data and size, and return a
 674 * "struct object".  If the object data we are returning is also borrowed
 675 * by the "struct object" representation, set *eaten as well---it is a
 676 * signal from parse_object_buffer to us not to free the buffer.
 677 */
 678static void *get_obj(const unsigned char *sha1, struct object **obj, unsigned long *sz, int *eaten)
 679{
 680        enum object_type type;
 681        void *buf = read_sha1_file(sha1, &type, sz);
 682
 683        if (buf)
 684                *obj = parse_object_buffer(sha1, type, *sz, buf, eaten);
 685        else
 686                *obj = NULL;
 687        return buf;
 688}
 689
 690static int grab_objectname(const char *name, const unsigned char *sha1,
 691                           struct atom_value *v, struct used_atom *atom)
 692{
 693        if (starts_with(name, "objectname")) {
 694                if (atom->u.objectname.option == O_SHORT) {
 695                        v->s = xstrdup(find_unique_abbrev(sha1, DEFAULT_ABBREV));
 696                        return 1;
 697                } else if (atom->u.objectname.option == O_FULL) {
 698                        v->s = xstrdup(sha1_to_hex(sha1));
 699                        return 1;
 700                } else if (atom->u.objectname.option == O_LENGTH) {
 701                        v->s = xstrdup(find_unique_abbrev(sha1, atom->u.objectname.length));
 702                        return 1;
 703                } else
 704                        die("BUG: unknown %%(objectname) option");
 705        }
 706        return 0;
 707}
 708
 709/* See grab_values */
 710static void grab_common_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 711{
 712        int i;
 713
 714        for (i = 0; i < used_atom_cnt; i++) {
 715                const char *name = used_atom[i].name;
 716                struct atom_value *v = &val[i];
 717                if (!!deref != (*name == '*'))
 718                        continue;
 719                if (deref)
 720                        name++;
 721                if (!strcmp(name, "objecttype"))
 722                        v->s = typename(obj->type);
 723                else if (!strcmp(name, "objectsize")) {
 724                        v->ul = sz;
 725                        v->s = xstrfmt("%lu", sz);
 726                }
 727                else if (deref)
 728                        grab_objectname(name, obj->oid.hash, v, &used_atom[i]);
 729        }
 730}
 731
 732/* See grab_values */
 733static void grab_tag_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 734{
 735        int i;
 736        struct tag *tag = (struct tag *) obj;
 737
 738        for (i = 0; i < used_atom_cnt; i++) {
 739                const char *name = used_atom[i].name;
 740                struct atom_value *v = &val[i];
 741                if (!!deref != (*name == '*'))
 742                        continue;
 743                if (deref)
 744                        name++;
 745                if (!strcmp(name, "tag"))
 746                        v->s = tag->tag;
 747                else if (!strcmp(name, "type") && tag->tagged)
 748                        v->s = typename(tag->tagged->type);
 749                else if (!strcmp(name, "object") && tag->tagged)
 750                        v->s = xstrdup(oid_to_hex(&tag->tagged->oid));
 751        }
 752}
 753
 754/* See grab_values */
 755static void grab_commit_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 756{
 757        int i;
 758        struct commit *commit = (struct commit *) obj;
 759
 760        for (i = 0; i < used_atom_cnt; i++) {
 761                const char *name = used_atom[i].name;
 762                struct atom_value *v = &val[i];
 763                if (!!deref != (*name == '*'))
 764                        continue;
 765                if (deref)
 766                        name++;
 767                if (!strcmp(name, "tree")) {
 768                        v->s = xstrdup(oid_to_hex(&commit->tree->object.oid));
 769                }
 770                else if (!strcmp(name, "numparent")) {
 771                        v->ul = commit_list_count(commit->parents);
 772                        v->s = xstrfmt("%lu", v->ul);
 773                }
 774                else if (!strcmp(name, "parent")) {
 775                        struct commit_list *parents;
 776                        struct strbuf s = STRBUF_INIT;
 777                        for (parents = commit->parents; parents; parents = parents->next) {
 778                                struct commit *parent = parents->item;
 779                                if (parents != commit->parents)
 780                                        strbuf_addch(&s, ' ');
 781                                strbuf_addstr(&s, oid_to_hex(&parent->object.oid));
 782                        }
 783                        v->s = strbuf_detach(&s, NULL);
 784                }
 785        }
 786}
 787
 788static const char *find_wholine(const char *who, int wholen, const char *buf, unsigned long sz)
 789{
 790        const char *eol;
 791        while (*buf) {
 792                if (!strncmp(buf, who, wholen) &&
 793                    buf[wholen] == ' ')
 794                        return buf + wholen + 1;
 795                eol = strchr(buf, '\n');
 796                if (!eol)
 797                        return "";
 798                eol++;
 799                if (*eol == '\n')
 800                        return ""; /* end of header */
 801                buf = eol;
 802        }
 803        return "";
 804}
 805
 806static const char *copy_line(const char *buf)
 807{
 808        const char *eol = strchrnul(buf, '\n');
 809        return xmemdupz(buf, eol - buf);
 810}
 811
 812static const char *copy_name(const char *buf)
 813{
 814        const char *cp;
 815        for (cp = buf; *cp && *cp != '\n'; cp++) {
 816                if (!strncmp(cp, " <", 2))
 817                        return xmemdupz(buf, cp - buf);
 818        }
 819        return "";
 820}
 821
 822static const char *copy_email(const char *buf)
 823{
 824        const char *email = strchr(buf, '<');
 825        const char *eoemail;
 826        if (!email)
 827                return "";
 828        eoemail = strchr(email, '>');
 829        if (!eoemail)
 830                return "";
 831        return xmemdupz(email, eoemail + 1 - email);
 832}
 833
 834static char *copy_subject(const char *buf, unsigned long len)
 835{
 836        char *r = xmemdupz(buf, len);
 837        int i;
 838
 839        for (i = 0; i < len; i++)
 840                if (r[i] == '\n')
 841                        r[i] = ' ';
 842
 843        return r;
 844}
 845
 846static void grab_date(const char *buf, struct atom_value *v, const char *atomname)
 847{
 848        const char *eoemail = strstr(buf, "> ");
 849        char *zone;
 850        unsigned long timestamp;
 851        long tz;
 852        struct date_mode date_mode = { DATE_NORMAL };
 853        const char *formatp;
 854
 855        /*
 856         * We got here because atomname ends in "date" or "date<something>";
 857         * it's not possible that <something> is not ":<format>" because
 858         * parse_ref_filter_atom() wouldn't have allowed it, so we can assume that no
 859         * ":" means no format is specified, and use the default.
 860         */
 861        formatp = strchr(atomname, ':');
 862        if (formatp != NULL) {
 863                formatp++;
 864                parse_date_format(formatp, &date_mode);
 865        }
 866
 867        if (!eoemail)
 868                goto bad;
 869        timestamp = strtoul(eoemail + 2, &zone, 10);
 870        if (timestamp == ULONG_MAX)
 871                goto bad;
 872        tz = strtol(zone, NULL, 10);
 873        if ((tz == LONG_MIN || tz == LONG_MAX) && errno == ERANGE)
 874                goto bad;
 875        v->s = xstrdup(show_date(timestamp, tz, &date_mode));
 876        v->ul = timestamp;
 877        return;
 878 bad:
 879        v->s = "";
 880        v->ul = 0;
 881}
 882
 883/* See grab_values */
 884static void grab_person(const char *who, struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 885{
 886        int i;
 887        int wholen = strlen(who);
 888        const char *wholine = NULL;
 889
 890        for (i = 0; i < used_atom_cnt; i++) {
 891                const char *name = used_atom[i].name;
 892                struct atom_value *v = &val[i];
 893                if (!!deref != (*name == '*'))
 894                        continue;
 895                if (deref)
 896                        name++;
 897                if (strncmp(who, name, wholen))
 898                        continue;
 899                if (name[wholen] != 0 &&
 900                    strcmp(name + wholen, "name") &&
 901                    strcmp(name + wholen, "email") &&
 902                    !starts_with(name + wholen, "date"))
 903                        continue;
 904                if (!wholine)
 905                        wholine = find_wholine(who, wholen, buf, sz);
 906                if (!wholine)
 907                        return; /* no point looking for it */
 908                if (name[wholen] == 0)
 909                        v->s = copy_line(wholine);
 910                else if (!strcmp(name + wholen, "name"))
 911                        v->s = copy_name(wholine);
 912                else if (!strcmp(name + wholen, "email"))
 913                        v->s = copy_email(wholine);
 914                else if (starts_with(name + wholen, "date"))
 915                        grab_date(wholine, v, name);
 916        }
 917
 918        /*
 919         * For a tag or a commit object, if "creator" or "creatordate" is
 920         * requested, do something special.
 921         */
 922        if (strcmp(who, "tagger") && strcmp(who, "committer"))
 923                return; /* "author" for commit object is not wanted */
 924        if (!wholine)
 925                wholine = find_wholine(who, wholen, buf, sz);
 926        if (!wholine)
 927                return;
 928        for (i = 0; i < used_atom_cnt; i++) {
 929                const char *name = used_atom[i].name;
 930                struct atom_value *v = &val[i];
 931                if (!!deref != (*name == '*'))
 932                        continue;
 933                if (deref)
 934                        name++;
 935
 936                if (starts_with(name, "creatordate"))
 937                        grab_date(wholine, v, name);
 938                else if (!strcmp(name, "creator"))
 939                        v->s = copy_line(wholine);
 940        }
 941}
 942
 943static void find_subpos(const char *buf, unsigned long sz,
 944                        const char **sub, unsigned long *sublen,
 945                        const char **body, unsigned long *bodylen,
 946                        unsigned long *nonsiglen,
 947                        const char **sig, unsigned long *siglen)
 948{
 949        const char *eol;
 950        /* skip past header until we hit empty line */
 951        while (*buf && *buf != '\n') {
 952                eol = strchrnul(buf, '\n');
 953                if (*eol)
 954                        eol++;
 955                buf = eol;
 956        }
 957        /* skip any empty lines */
 958        while (*buf == '\n')
 959                buf++;
 960
 961        /* parse signature first; we might not even have a subject line */
 962        *sig = buf + parse_signature(buf, strlen(buf));
 963        *siglen = strlen(*sig);
 964
 965        /* subject is first non-empty line */
 966        *sub = buf;
 967        /* subject goes to first empty line */
 968        while (buf < *sig && *buf && *buf != '\n') {
 969                eol = strchrnul(buf, '\n');
 970                if (*eol)
 971                        eol++;
 972                buf = eol;
 973        }
 974        *sublen = buf - *sub;
 975        /* drop trailing newline, if present */
 976        if (*sublen && (*sub)[*sublen - 1] == '\n')
 977                *sublen -= 1;
 978
 979        /* skip any empty lines */
 980        while (*buf == '\n')
 981                buf++;
 982        *body = buf;
 983        *bodylen = strlen(buf);
 984        *nonsiglen = *sig - buf;
 985}
 986
 987/*
 988 * If 'lines' is greater than 0, append that many lines from the given
 989 * 'buf' of length 'size' to the given strbuf.
 990 */
 991static void append_lines(struct strbuf *out, const char *buf, unsigned long size, int lines)
 992{
 993        int i;
 994        const char *sp, *eol;
 995        size_t len;
 996
 997        sp = buf;
 998
 999        for (i = 0; i < lines && sp < buf + size; i++) {
1000                if (i)
1001                        strbuf_addstr(out, "\n    ");
1002                eol = memchr(sp, '\n', size - (sp - buf));
1003                len = eol ? eol - sp : size - (sp - buf);
1004                strbuf_add(out, sp, len);
1005                if (!eol)
1006                        break;
1007                sp = eol + 1;
1008        }
1009}
1010
1011/* See grab_values */
1012static void grab_sub_body_contents(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
1013{
1014        int i;
1015        const char *subpos = NULL, *bodypos = NULL, *sigpos = NULL;
1016        unsigned long sublen = 0, bodylen = 0, nonsiglen = 0, siglen = 0;
1017
1018        for (i = 0; i < used_atom_cnt; i++) {
1019                struct used_atom *atom = &used_atom[i];
1020                const char *name = atom->name;
1021                struct atom_value *v = &val[i];
1022                if (!!deref != (*name == '*'))
1023                        continue;
1024                if (deref)
1025                        name++;
1026                if (strcmp(name, "subject") &&
1027                    strcmp(name, "body") &&
1028                    strcmp(name, "trailers") &&
1029                    !starts_with(name, "contents"))
1030                        continue;
1031                if (!subpos)
1032                        find_subpos(buf, sz,
1033                                    &subpos, &sublen,
1034                                    &bodypos, &bodylen, &nonsiglen,
1035                                    &sigpos, &siglen);
1036
1037                if (atom->u.contents.option == C_SUB)
1038                        v->s = copy_subject(subpos, sublen);
1039                else if (atom->u.contents.option == C_BODY_DEP)
1040                        v->s = xmemdupz(bodypos, bodylen);
1041                else if (atom->u.contents.option == C_BODY)
1042                        v->s = xmemdupz(bodypos, nonsiglen);
1043                else if (atom->u.contents.option == C_SIG)
1044                        v->s = xmemdupz(sigpos, siglen);
1045                else if (atom->u.contents.option == C_LINES) {
1046                        struct strbuf s = STRBUF_INIT;
1047                        const char *contents_end = bodylen + bodypos - siglen;
1048
1049                        /*  Size is the length of the message after removing the signature */
1050                        append_lines(&s, subpos, contents_end - subpos, atom->u.contents.nlines);
1051                        v->s = strbuf_detach(&s, NULL);
1052                } else if (atom->u.contents.option == C_TRAILERS) {
1053                        struct trailer_info info;
1054
1055                        /* Search for trailer info */
1056                        trailer_info_get(&info, subpos);
1057                        v->s = xmemdupz(info.trailer_start,
1058                                        info.trailer_end - info.trailer_start);
1059                        trailer_info_release(&info);
1060                } else if (atom->u.contents.option == C_BARE)
1061                        v->s = xstrdup(subpos);
1062        }
1063}
1064
1065/*
1066 * We want to have empty print-string for field requests
1067 * that do not apply (e.g. "authordate" for a tag object)
1068 */
1069static void fill_missing_values(struct atom_value *val)
1070{
1071        int i;
1072        for (i = 0; i < used_atom_cnt; i++) {
1073                struct atom_value *v = &val[i];
1074                if (v->s == NULL)
1075                        v->s = "";
1076        }
1077}
1078
1079/*
1080 * val is a list of atom_value to hold returned values.  Extract
1081 * the values for atoms in used_atom array out of (obj, buf, sz).
1082 * when deref is false, (obj, buf, sz) is the object that is
1083 * pointed at by the ref itself; otherwise it is the object the
1084 * ref (which is a tag) refers to.
1085 */
1086static void grab_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
1087{
1088        grab_common_values(val, deref, obj, buf, sz);
1089        switch (obj->type) {
1090        case OBJ_TAG:
1091                grab_tag_values(val, deref, obj, buf, sz);
1092                grab_sub_body_contents(val, deref, obj, buf, sz);
1093                grab_person("tagger", val, deref, obj, buf, sz);
1094                break;
1095        case OBJ_COMMIT:
1096                grab_commit_values(val, deref, obj, buf, sz);
1097                grab_sub_body_contents(val, deref, obj, buf, sz);
1098                grab_person("author", val, deref, obj, buf, sz);
1099                grab_person("committer", val, deref, obj, buf, sz);
1100                break;
1101        case OBJ_TREE:
1102                /* grab_tree_values(val, deref, obj, buf, sz); */
1103                break;
1104        case OBJ_BLOB:
1105                /* grab_blob_values(val, deref, obj, buf, sz); */
1106                break;
1107        default:
1108                die("Eh?  Object of type %d?", obj->type);
1109        }
1110}
1111
1112static inline char *copy_advance(char *dst, const char *src)
1113{
1114        while (*src)
1115                *dst++ = *src++;
1116        return dst;
1117}
1118
1119static const char *lstrip_ref_components(const char *refname, int len)
1120{
1121        long remaining = len;
1122        const char *start = refname;
1123
1124        if (len < 0) {
1125                int i;
1126                const char *p = refname;
1127
1128                /* Find total no of '/' separated path-components */
1129                for (i = 0; p[i]; p[i] == '/' ? i++ : *p++)
1130                        ;
1131                /*
1132                 * The number of components we need to strip is now
1133                 * the total minus the components to be left (Plus one
1134                 * because we count the number of '/', but the number
1135                 * of components is one more than the no of '/').
1136                 */
1137                remaining = i + len + 1;
1138        }
1139
1140        while (remaining > 0) {
1141                switch (*start++) {
1142                case '\0':
1143                        return "";
1144                case '/':
1145                        remaining--;
1146                        break;
1147                }
1148        }
1149
1150        return start;
1151}
1152
1153static const char *rstrip_ref_components(const char *refname, int len)
1154{
1155        long remaining = len;
1156        char *start = xstrdup(refname);
1157
1158        if (len < 0) {
1159                int i;
1160                const char *p = refname;
1161
1162                /* Find total no of '/' separated path-components */
1163                for (i = 0; p[i]; p[i] == '/' ? i++ : *p++)
1164                        ;
1165                /*
1166                 * The number of components we need to strip is now
1167                 * the total minus the components to be left (Plus one
1168                 * because we count the number of '/', but the number
1169                 * of components is one more than the no of '/').
1170                 */
1171                remaining = i + len + 1;
1172        }
1173
1174        while (remaining-- > 0) {
1175                char *p = strrchr(start, '/');
1176                if (p == NULL)
1177                        return "";
1178                else
1179                        p[0] = '\0';
1180        }
1181        return start;
1182}
1183
1184static const char *show_ref(struct refname_atom *atom, const char *refname)
1185{
1186        if (atom->option == R_SHORT)
1187                return shorten_unambiguous_ref(refname, warn_ambiguous_refs);
1188        else if (atom->option == R_LSTRIP)
1189                return lstrip_ref_components(refname, atom->lstrip);
1190        else if (atom->option == R_RSTRIP)
1191                return rstrip_ref_components(refname, atom->rstrip);
1192        else
1193                return refname;
1194}
1195
1196static void fill_remote_ref_details(struct used_atom *atom, const char *refname,
1197                                    struct branch *branch, const char **s)
1198{
1199        int num_ours, num_theirs;
1200        if (atom->u.remote_ref.option == RR_REF)
1201                *s = show_ref(&atom->u.remote_ref.refname, refname);
1202        else if (atom->u.remote_ref.option == RR_TRACK) {
1203                if (stat_tracking_info(branch, &num_ours,
1204                                       &num_theirs, NULL)) {
1205                        *s = xstrdup(msgs.gone);
1206                } else if (!num_ours && !num_theirs)
1207                        *s = "";
1208                else if (!num_ours)
1209                        *s = xstrfmt(msgs.behind, num_theirs);
1210                else if (!num_theirs)
1211                        *s = xstrfmt(msgs.ahead, num_ours);
1212                else
1213                        *s = xstrfmt(msgs.ahead_behind,
1214                                     num_ours, num_theirs);
1215                if (!atom->u.remote_ref.nobracket && *s[0]) {
1216                        const char *to_free = *s;
1217                        *s = xstrfmt("[%s]", *s);
1218                        free((void *)to_free);
1219                }
1220        } else if (atom->u.remote_ref.option == RR_TRACKSHORT) {
1221                if (stat_tracking_info(branch, &num_ours,
1222                                       &num_theirs, NULL))
1223                        return;
1224
1225                if (!num_ours && !num_theirs)
1226                        *s = "=";
1227                else if (!num_ours)
1228                        *s = "<";
1229                else if (!num_theirs)
1230                        *s = ">";
1231                else
1232                        *s = "<>";
1233        } else
1234                die("BUG: unhandled RR_* enum");
1235}
1236
1237char *get_head_description(void)
1238{
1239        struct strbuf desc = STRBUF_INIT;
1240        struct wt_status_state state;
1241        memset(&state, 0, sizeof(state));
1242        wt_status_get_state(&state, 1);
1243        if (state.rebase_in_progress ||
1244            state.rebase_interactive_in_progress)
1245                strbuf_addf(&desc, _("(no branch, rebasing %s)"),
1246                            state.branch);
1247        else if (state.bisect_in_progress)
1248                strbuf_addf(&desc, _("(no branch, bisect started on %s)"),
1249                            state.branch);
1250        else if (state.detached_from) {
1251                /* TRANSLATORS: make sure these match _("HEAD detached at ")
1252                   and _("HEAD detached from ") in wt-status.c */
1253                if (state.detached_at)
1254                        strbuf_addf(&desc, _("(HEAD detached at %s)"),
1255                                state.detached_from);
1256                else
1257                        strbuf_addf(&desc, _("(HEAD detached from %s)"),
1258                                state.detached_from);
1259        }
1260        else
1261                strbuf_addstr(&desc, _("(no branch)"));
1262        free(state.branch);
1263        free(state.onto);
1264        free(state.detached_from);
1265        return strbuf_detach(&desc, NULL);
1266}
1267
1268static const char *get_symref(struct used_atom *atom, struct ref_array_item *ref)
1269{
1270        if (!ref->symref)
1271                return "";
1272        else
1273                return show_ref(&atom->u.refname, ref->symref);
1274}
1275
1276static const char *get_refname(struct used_atom *atom, struct ref_array_item *ref)
1277{
1278        if (ref->kind & FILTER_REFS_DETACHED_HEAD)
1279                return get_head_description();
1280        return show_ref(&atom->u.refname, ref->refname);
1281}
1282
1283/*
1284 * Parse the object referred by ref, and grab needed value.
1285 */
1286static void populate_value(struct ref_array_item *ref)
1287{
1288        void *buf;
1289        struct object *obj;
1290        int eaten, i;
1291        unsigned long size;
1292        const unsigned char *tagged;
1293
1294        ref->value = xcalloc(used_atom_cnt, sizeof(struct atom_value));
1295
1296        if (need_symref && (ref->flag & REF_ISSYMREF) && !ref->symref) {
1297                unsigned char unused1[20];
1298                ref->symref = resolve_refdup(ref->refname, RESOLVE_REF_READING,
1299                                             unused1, NULL);
1300                if (!ref->symref)
1301                        ref->symref = "";
1302        }
1303
1304        /* Fill in specials first */
1305        for (i = 0; i < used_atom_cnt; i++) {
1306                struct used_atom *atom = &used_atom[i];
1307                const char *name = used_atom[i].name;
1308                struct atom_value *v = &ref->value[i];
1309                int deref = 0;
1310                const char *refname;
1311                struct branch *branch = NULL;
1312
1313                v->handler = append_atom;
1314                v->atom = atom;
1315
1316                if (*name == '*') {
1317                        deref = 1;
1318                        name++;
1319                }
1320
1321                if (starts_with(name, "refname"))
1322                        refname = get_refname(atom, ref);
1323                else if (starts_with(name, "symref"))
1324                        refname = get_symref(atom, ref);
1325                else if (starts_with(name, "upstream")) {
1326                        const char *branch_name;
1327                        /* only local branches may have an upstream */
1328                        if (!skip_prefix(ref->refname, "refs/heads/",
1329                                         &branch_name))
1330                                continue;
1331                        branch = branch_get(branch_name);
1332
1333                        refname = branch_get_upstream(branch, NULL);
1334                        if (refname)
1335                                fill_remote_ref_details(atom, refname, branch, &v->s);
1336                        continue;
1337                } else if (starts_with(name, "push")) {
1338                        const char *branch_name;
1339                        if (!skip_prefix(ref->refname, "refs/heads/",
1340                                         &branch_name))
1341                                continue;
1342                        branch = branch_get(branch_name);
1343
1344                        refname = branch_get_push(branch, NULL);
1345                        if (!refname)
1346                                continue;
1347                        fill_remote_ref_details(atom, refname, branch, &v->s);
1348                        continue;
1349                } else if (starts_with(name, "color:")) {
1350                        v->s = atom->u.color;
1351                        continue;
1352                } else if (!strcmp(name, "flag")) {
1353                        char buf[256], *cp = buf;
1354                        if (ref->flag & REF_ISSYMREF)
1355                                cp = copy_advance(cp, ",symref");
1356                        if (ref->flag & REF_ISPACKED)
1357                                cp = copy_advance(cp, ",packed");
1358                        if (cp == buf)
1359                                v->s = "";
1360                        else {
1361                                *cp = '\0';
1362                                v->s = xstrdup(buf + 1);
1363                        }
1364                        continue;
1365                } else if (!deref && grab_objectname(name, ref->objectname, v, atom)) {
1366                        continue;
1367                } else if (!strcmp(name, "HEAD")) {
1368                        const char *head;
1369                        unsigned char sha1[20];
1370
1371                        head = resolve_ref_unsafe("HEAD", RESOLVE_REF_READING,
1372                                                  sha1, NULL);
1373                        if (head && !strcmp(ref->refname, head))
1374                                v->s = "*";
1375                        else
1376                                v->s = " ";
1377                        continue;
1378                } else if (starts_with(name, "align")) {
1379                        v->handler = align_atom_handler;
1380                        continue;
1381                } else if (!strcmp(name, "end")) {
1382                        v->handler = end_atom_handler;
1383                        continue;
1384                } else if (starts_with(name, "if")) {
1385                        const char *s;
1386
1387                        if (skip_prefix(name, "if:", &s))
1388                                v->s = xstrdup(s);
1389                        v->handler = if_atom_handler;
1390                        continue;
1391                } else if (!strcmp(name, "then")) {
1392                        v->handler = then_atom_handler;
1393                        continue;
1394                } else if (!strcmp(name, "else")) {
1395                        v->handler = else_atom_handler;
1396                        continue;
1397                } else
1398                        continue;
1399
1400                if (!deref)
1401                        v->s = refname;
1402                else
1403                        v->s = xstrfmt("%s^{}", refname);
1404        }
1405
1406        for (i = 0; i < used_atom_cnt; i++) {
1407                struct atom_value *v = &ref->value[i];
1408                if (v->s == NULL)
1409                        goto need_obj;
1410        }
1411        return;
1412
1413 need_obj:
1414        buf = get_obj(ref->objectname, &obj, &size, &eaten);
1415        if (!buf)
1416                die(_("missing object %s for %s"),
1417                    sha1_to_hex(ref->objectname), ref->refname);
1418        if (!obj)
1419                die(_("parse_object_buffer failed on %s for %s"),
1420                    sha1_to_hex(ref->objectname), ref->refname);
1421
1422        grab_values(ref->value, 0, obj, buf, size);
1423        if (!eaten)
1424                free(buf);
1425
1426        /*
1427         * If there is no atom that wants to know about tagged
1428         * object, we are done.
1429         */
1430        if (!need_tagged || (obj->type != OBJ_TAG))
1431                return;
1432
1433        /*
1434         * If it is a tag object, see if we use a value that derefs
1435         * the object, and if we do grab the object it refers to.
1436         */
1437        tagged = ((struct tag *)obj)->tagged->oid.hash;
1438
1439        /*
1440         * NEEDSWORK: This derefs tag only once, which
1441         * is good to deal with chains of trust, but
1442         * is not consistent with what deref_tag() does
1443         * which peels the onion to the core.
1444         */
1445        buf = get_obj(tagged, &obj, &size, &eaten);
1446        if (!buf)
1447                die(_("missing object %s for %s"),
1448                    sha1_to_hex(tagged), ref->refname);
1449        if (!obj)
1450                die(_("parse_object_buffer failed on %s for %s"),
1451                    sha1_to_hex(tagged), ref->refname);
1452        grab_values(ref->value, 1, obj, buf, size);
1453        if (!eaten)
1454                free(buf);
1455}
1456
1457/*
1458 * Given a ref, return the value for the atom.  This lazily gets value
1459 * out of the object by calling populate value.
1460 */
1461static void get_ref_atom_value(struct ref_array_item *ref, int atom, struct atom_value **v)
1462{
1463        if (!ref->value) {
1464                populate_value(ref);
1465                fill_missing_values(ref->value);
1466        }
1467        *v = &ref->value[atom];
1468}
1469
1470enum contains_result {
1471        CONTAINS_UNKNOWN = -1,
1472        CONTAINS_NO = 0,
1473        CONTAINS_YES = 1
1474};
1475
1476/*
1477 * Mimicking the real stack, this stack lives on the heap, avoiding stack
1478 * overflows.
1479 *
1480 * At each recursion step, the stack items points to the commits whose
1481 * ancestors are to be inspected.
1482 */
1483struct contains_stack {
1484        int nr, alloc;
1485        struct contains_stack_entry {
1486                struct commit *commit;
1487                struct commit_list *parents;
1488        } *contains_stack;
1489};
1490
1491static int in_commit_list(const struct commit_list *want, struct commit *c)
1492{
1493        for (; want; want = want->next)
1494                if (!oidcmp(&want->item->object.oid, &c->object.oid))
1495                        return 1;
1496        return 0;
1497}
1498
1499/*
1500 * Test whether the candidate or one of its parents is contained in the list.
1501 * Do not recurse to find out, though, but return -1 if inconclusive.
1502 */
1503static enum contains_result contains_test(struct commit *candidate,
1504                            const struct commit_list *want)
1505{
1506        /* was it previously marked as containing a want commit? */
1507        if (candidate->object.flags & TMP_MARK)
1508                return 1;
1509        /* or marked as not possibly containing a want commit? */
1510        if (candidate->object.flags & UNINTERESTING)
1511                return 0;
1512        /* or are we it? */
1513        if (in_commit_list(want, candidate)) {
1514                candidate->object.flags |= TMP_MARK;
1515                return 1;
1516        }
1517
1518        if (parse_commit(candidate) < 0)
1519                return 0;
1520
1521        return -1;
1522}
1523
1524static void push_to_contains_stack(struct commit *candidate, struct contains_stack *contains_stack)
1525{
1526        ALLOC_GROW(contains_stack->contains_stack, contains_stack->nr + 1, contains_stack->alloc);
1527        contains_stack->contains_stack[contains_stack->nr].commit = candidate;
1528        contains_stack->contains_stack[contains_stack->nr++].parents = candidate->parents;
1529}
1530
1531static enum contains_result contains_tag_algo(struct commit *candidate,
1532                const struct commit_list *want)
1533{
1534        struct contains_stack contains_stack = { 0, 0, NULL };
1535        int result = contains_test(candidate, want);
1536
1537        if (result != CONTAINS_UNKNOWN)
1538                return result;
1539
1540        push_to_contains_stack(candidate, &contains_stack);
1541        while (contains_stack.nr) {
1542                struct contains_stack_entry *entry = &contains_stack.contains_stack[contains_stack.nr - 1];
1543                struct commit *commit = entry->commit;
1544                struct commit_list *parents = entry->parents;
1545
1546                if (!parents) {
1547                        commit->object.flags |= UNINTERESTING;
1548                        contains_stack.nr--;
1549                }
1550                /*
1551                 * If we just popped the stack, parents->item has been marked,
1552                 * therefore contains_test will return a meaningful 0 or 1.
1553                 */
1554                else switch (contains_test(parents->item, want)) {
1555                case CONTAINS_YES:
1556                        commit->object.flags |= TMP_MARK;
1557                        contains_stack.nr--;
1558                        break;
1559                case CONTAINS_NO:
1560                        entry->parents = parents->next;
1561                        break;
1562                case CONTAINS_UNKNOWN:
1563                        push_to_contains_stack(parents->item, &contains_stack);
1564                        break;
1565                }
1566        }
1567        free(contains_stack.contains_stack);
1568        return contains_test(candidate, want);
1569}
1570
1571static int commit_contains(struct ref_filter *filter, struct commit *commit)
1572{
1573        if (filter->with_commit_tag_algo)
1574                return contains_tag_algo(commit, filter->with_commit);
1575        return is_descendant_of(commit, filter->with_commit);
1576}
1577
1578/*
1579 * Return 1 if the refname matches one of the patterns, otherwise 0.
1580 * A pattern can be a literal prefix (e.g. a refname "refs/heads/master"
1581 * matches a pattern "refs/heads/mas") or a wildcard (e.g. the same ref
1582 * matches "refs/heads/mas*", too).
1583 */
1584static int match_pattern(const struct ref_filter *filter, const char *refname)
1585{
1586        const char **patterns = filter->name_patterns;
1587        unsigned flags = 0;
1588
1589        if (filter->ignore_case)
1590                flags |= WM_CASEFOLD;
1591
1592        /*
1593         * When no '--format' option is given we need to skip the prefix
1594         * for matching refs of tags and branches.
1595         */
1596        (void)(skip_prefix(refname, "refs/tags/", &refname) ||
1597               skip_prefix(refname, "refs/heads/", &refname) ||
1598               skip_prefix(refname, "refs/remotes/", &refname) ||
1599               skip_prefix(refname, "refs/", &refname));
1600
1601        for (; *patterns; patterns++) {
1602                if (!wildmatch(*patterns, refname, flags, NULL))
1603                        return 1;
1604        }
1605        return 0;
1606}
1607
1608/*
1609 * Return 1 if the refname matches one of the patterns, otherwise 0.
1610 * A pattern can be path prefix (e.g. a refname "refs/heads/master"
1611 * matches a pattern "refs/heads/" but not "refs/heads/m") or a
1612 * wildcard (e.g. the same ref matches "refs/heads/m*", too).
1613 */
1614static int match_name_as_path(const struct ref_filter *filter, const char *refname)
1615{
1616        const char **pattern = filter->name_patterns;
1617        int namelen = strlen(refname);
1618        unsigned flags = WM_PATHNAME;
1619
1620        if (filter->ignore_case)
1621                flags |= WM_CASEFOLD;
1622
1623        for (; *pattern; pattern++) {
1624                const char *p = *pattern;
1625                int plen = strlen(p);
1626
1627                if ((plen <= namelen) &&
1628                    !strncmp(refname, p, plen) &&
1629                    (refname[plen] == '\0' ||
1630                     refname[plen] == '/' ||
1631                     p[plen-1] == '/'))
1632                        return 1;
1633                if (!wildmatch(p, refname, WM_PATHNAME, NULL))
1634                        return 1;
1635        }
1636        return 0;
1637}
1638
1639/* Return 1 if the refname matches one of the patterns, otherwise 0. */
1640static int filter_pattern_match(struct ref_filter *filter, const char *refname)
1641{
1642        if (!*filter->name_patterns)
1643                return 1; /* No pattern always matches */
1644        if (filter->match_as_path)
1645                return match_name_as_path(filter, refname);
1646        return match_pattern(filter, refname);
1647}
1648
1649/*
1650 * Given a ref (sha1, refname), check if the ref belongs to the array
1651 * of sha1s. If the given ref is a tag, check if the given tag points
1652 * at one of the sha1s in the given sha1 array.
1653 * the given sha1_array.
1654 * NEEDSWORK:
1655 * 1. Only a single level of inderection is obtained, we might want to
1656 * change this to account for multiple levels (e.g. annotated tags
1657 * pointing to annotated tags pointing to a commit.)
1658 * 2. As the refs are cached we might know what refname peels to without
1659 * the need to parse the object via parse_object(). peel_ref() might be a
1660 * more efficient alternative to obtain the pointee.
1661 */
1662static const unsigned char *match_points_at(struct sha1_array *points_at,
1663                                            const unsigned char *sha1,
1664                                            const char *refname)
1665{
1666        const unsigned char *tagged_sha1 = NULL;
1667        struct object *obj;
1668
1669        if (sha1_array_lookup(points_at, sha1) >= 0)
1670                return sha1;
1671        obj = parse_object(sha1);
1672        if (!obj)
1673                die(_("malformed object at '%s'"), refname);
1674        if (obj->type == OBJ_TAG)
1675                tagged_sha1 = ((struct tag *)obj)->tagged->oid.hash;
1676        if (tagged_sha1 && sha1_array_lookup(points_at, tagged_sha1) >= 0)
1677                return tagged_sha1;
1678        return NULL;
1679}
1680
1681/* Allocate space for a new ref_array_item and copy the objectname and flag to it */
1682static struct ref_array_item *new_ref_array_item(const char *refname,
1683                                                 const unsigned char *objectname,
1684                                                 int flag)
1685{
1686        struct ref_array_item *ref;
1687        FLEX_ALLOC_STR(ref, refname, refname);
1688        hashcpy(ref->objectname, objectname);
1689        ref->flag = flag;
1690
1691        return ref;
1692}
1693
1694static int filter_ref_kind(struct ref_filter *filter, const char *refname)
1695{
1696        unsigned int i;
1697
1698        static struct {
1699                const char *prefix;
1700                unsigned int kind;
1701        } ref_kind[] = {
1702                { "refs/heads/" , FILTER_REFS_BRANCHES },
1703                { "refs/remotes/" , FILTER_REFS_REMOTES },
1704                { "refs/tags/", FILTER_REFS_TAGS}
1705        };
1706
1707        if (filter->kind == FILTER_REFS_BRANCHES ||
1708            filter->kind == FILTER_REFS_REMOTES ||
1709            filter->kind == FILTER_REFS_TAGS)
1710                return filter->kind;
1711        else if (!strcmp(refname, "HEAD"))
1712                return FILTER_REFS_DETACHED_HEAD;
1713
1714        for (i = 0; i < ARRAY_SIZE(ref_kind); i++) {
1715                if (starts_with(refname, ref_kind[i].prefix))
1716                        return ref_kind[i].kind;
1717        }
1718
1719        return FILTER_REFS_OTHERS;
1720}
1721
1722/*
1723 * A call-back given to for_each_ref().  Filter refs and keep them for
1724 * later object processing.
1725 */
1726static int ref_filter_handler(const char *refname, const struct object_id *oid, int flag, void *cb_data)
1727{
1728        struct ref_filter_cbdata *ref_cbdata = cb_data;
1729        struct ref_filter *filter = ref_cbdata->filter;
1730        struct ref_array_item *ref;
1731        struct commit *commit = NULL;
1732        unsigned int kind;
1733
1734        if (flag & REF_BAD_NAME) {
1735                warning(_("ignoring ref with broken name %s"), refname);
1736                return 0;
1737        }
1738
1739        if (flag & REF_ISBROKEN) {
1740                warning(_("ignoring broken ref %s"), refname);
1741                return 0;
1742        }
1743
1744        /* Obtain the current ref kind from filter_ref_kind() and ignore unwanted refs. */
1745        kind = filter_ref_kind(filter, refname);
1746        if (!(kind & filter->kind))
1747                return 0;
1748
1749        if (!filter_pattern_match(filter, refname))
1750                return 0;
1751
1752        if (filter->points_at.nr && !match_points_at(&filter->points_at, oid->hash, refname))
1753                return 0;
1754
1755        /*
1756         * A merge filter is applied on refs pointing to commits. Hence
1757         * obtain the commit using the 'oid' available and discard all
1758         * non-commits early. The actual filtering is done later.
1759         */
1760        if (filter->merge_commit || filter->with_commit || filter->verbose) {
1761                commit = lookup_commit_reference_gently(oid->hash, 1);
1762                if (!commit)
1763                        return 0;
1764                /* We perform the filtering for the '--contains' option */
1765                if (filter->with_commit &&
1766                    !commit_contains(filter, commit))
1767                        return 0;
1768        }
1769
1770        /*
1771         * We do not open the object yet; sort may only need refname
1772         * to do its job and the resulting list may yet to be pruned
1773         * by maxcount logic.
1774         */
1775        ref = new_ref_array_item(refname, oid->hash, flag);
1776        ref->commit = commit;
1777
1778        REALLOC_ARRAY(ref_cbdata->array->items, ref_cbdata->array->nr + 1);
1779        ref_cbdata->array->items[ref_cbdata->array->nr++] = ref;
1780        ref->kind = kind;
1781        return 0;
1782}
1783
1784/*  Free memory allocated for a ref_array_item */
1785static void free_array_item(struct ref_array_item *item)
1786{
1787        free((char *)item->symref);
1788        free(item);
1789}
1790
1791/* Free all memory allocated for ref_array */
1792void ref_array_clear(struct ref_array *array)
1793{
1794        int i;
1795
1796        for (i = 0; i < array->nr; i++)
1797                free_array_item(array->items[i]);
1798        free(array->items);
1799        array->items = NULL;
1800        array->nr = array->alloc = 0;
1801}
1802
1803static void do_merge_filter(struct ref_filter_cbdata *ref_cbdata)
1804{
1805        struct rev_info revs;
1806        int i, old_nr;
1807        struct ref_filter *filter = ref_cbdata->filter;
1808        struct ref_array *array = ref_cbdata->array;
1809        struct commit **to_clear = xcalloc(sizeof(struct commit *), array->nr);
1810
1811        init_revisions(&revs, NULL);
1812
1813        for (i = 0; i < array->nr; i++) {
1814                struct ref_array_item *item = array->items[i];
1815                add_pending_object(&revs, &item->commit->object, item->refname);
1816                to_clear[i] = item->commit;
1817        }
1818
1819        filter->merge_commit->object.flags |= UNINTERESTING;
1820        add_pending_object(&revs, &filter->merge_commit->object, "");
1821
1822        revs.limited = 1;
1823        if (prepare_revision_walk(&revs))
1824                die(_("revision walk setup failed"));
1825
1826        old_nr = array->nr;
1827        array->nr = 0;
1828
1829        for (i = 0; i < old_nr; i++) {
1830                struct ref_array_item *item = array->items[i];
1831                struct commit *commit = item->commit;
1832
1833                int is_merged = !!(commit->object.flags & UNINTERESTING);
1834
1835                if (is_merged == (filter->merge == REF_FILTER_MERGED_INCLUDE))
1836                        array->items[array->nr++] = array->items[i];
1837                else
1838                        free_array_item(item);
1839        }
1840
1841        for (i = 0; i < old_nr; i++)
1842                clear_commit_marks(to_clear[i], ALL_REV_FLAGS);
1843        clear_commit_marks(filter->merge_commit, ALL_REV_FLAGS);
1844        free(to_clear);
1845}
1846
1847/*
1848 * API for filtering a set of refs. Based on the type of refs the user
1849 * has requested, we iterate through those refs and apply filters
1850 * as per the given ref_filter structure and finally store the
1851 * filtered refs in the ref_array structure.
1852 */
1853int filter_refs(struct ref_array *array, struct ref_filter *filter, unsigned int type)
1854{
1855        struct ref_filter_cbdata ref_cbdata;
1856        int ret = 0;
1857        unsigned int broken = 0;
1858
1859        ref_cbdata.array = array;
1860        ref_cbdata.filter = filter;
1861
1862        if (type & FILTER_REFS_INCLUDE_BROKEN)
1863                broken = 1;
1864        filter->kind = type & FILTER_REFS_KIND_MASK;
1865
1866        /*  Simple per-ref filtering */
1867        if (!filter->kind)
1868                die("filter_refs: invalid type");
1869        else {
1870                /*
1871                 * For common cases where we need only branches or remotes or tags,
1872                 * we only iterate through those refs. If a mix of refs is needed,
1873                 * we iterate over all refs and filter out required refs with the help
1874                 * of filter_ref_kind().
1875                 */
1876                if (filter->kind == FILTER_REFS_BRANCHES)
1877                        ret = for_each_fullref_in("refs/heads/", ref_filter_handler, &ref_cbdata, broken);
1878                else if (filter->kind == FILTER_REFS_REMOTES)
1879                        ret = for_each_fullref_in("refs/remotes/", ref_filter_handler, &ref_cbdata, broken);
1880                else if (filter->kind == FILTER_REFS_TAGS)
1881                        ret = for_each_fullref_in("refs/tags/", ref_filter_handler, &ref_cbdata, broken);
1882                else if (filter->kind & FILTER_REFS_ALL)
1883                        ret = for_each_fullref_in("", ref_filter_handler, &ref_cbdata, broken);
1884                if (!ret && (filter->kind & FILTER_REFS_DETACHED_HEAD))
1885                        head_ref(ref_filter_handler, &ref_cbdata);
1886        }
1887
1888
1889        /*  Filters that need revision walking */
1890        if (filter->merge_commit)
1891                do_merge_filter(&ref_cbdata);
1892
1893        return ret;
1894}
1895
1896static int cmp_ref_sorting(struct ref_sorting *s, struct ref_array_item *a, struct ref_array_item *b)
1897{
1898        struct atom_value *va, *vb;
1899        int cmp;
1900        cmp_type cmp_type = used_atom[s->atom].type;
1901        int (*cmp_fn)(const char *, const char *);
1902
1903        get_ref_atom_value(a, s->atom, &va);
1904        get_ref_atom_value(b, s->atom, &vb);
1905        cmp_fn = s->ignore_case ? strcasecmp : strcmp;
1906        if (s->version)
1907                cmp = versioncmp(va->s, vb->s);
1908        else if (cmp_type == FIELD_STR)
1909                cmp = cmp_fn(va->s, vb->s);
1910        else {
1911                if (va->ul < vb->ul)
1912                        cmp = -1;
1913                else if (va->ul == vb->ul)
1914                        cmp = cmp_fn(a->refname, b->refname);
1915                else
1916                        cmp = 1;
1917        }
1918
1919        return (s->reverse) ? -cmp : cmp;
1920}
1921
1922static struct ref_sorting *ref_sorting;
1923static int compare_refs(const void *a_, const void *b_)
1924{
1925        struct ref_array_item *a = *((struct ref_array_item **)a_);
1926        struct ref_array_item *b = *((struct ref_array_item **)b_);
1927        struct ref_sorting *s;
1928
1929        for (s = ref_sorting; s; s = s->next) {
1930                int cmp = cmp_ref_sorting(s, a, b);
1931                if (cmp)
1932                        return cmp;
1933        }
1934        return 0;
1935}
1936
1937void ref_array_sort(struct ref_sorting *sorting, struct ref_array *array)
1938{
1939        ref_sorting = sorting;
1940        QSORT(array->items, array->nr, compare_refs);
1941}
1942
1943static void append_literal(const char *cp, const char *ep, struct ref_formatting_state *state)
1944{
1945        struct strbuf *s = &state->stack->output;
1946
1947        while (*cp && (!ep || cp < ep)) {
1948                if (*cp == '%') {
1949                        if (cp[1] == '%')
1950                                cp++;
1951                        else {
1952                                int ch = hex2chr(cp + 1);
1953                                if (0 <= ch) {
1954                                        strbuf_addch(s, ch);
1955                                        cp += 3;
1956                                        continue;
1957                                }
1958                        }
1959                }
1960                strbuf_addch(s, *cp);
1961                cp++;
1962        }
1963}
1964
1965void format_ref_array_item(struct ref_array_item *info, const char *format,
1966                           int quote_style, struct strbuf *final_buf)
1967{
1968        const char *cp, *sp, *ep;
1969        struct ref_formatting_state state = REF_FORMATTING_STATE_INIT;
1970
1971        state.quote_style = quote_style;
1972        push_stack_element(&state.stack);
1973
1974        for (cp = format; *cp && (sp = find_next(cp)); cp = ep + 1) {
1975                struct atom_value *atomv;
1976
1977                ep = strchr(sp, ')');
1978                if (cp < sp)
1979                        append_literal(cp, sp, &state);
1980                get_ref_atom_value(info, parse_ref_filter_atom(sp + 2, ep), &atomv);
1981                atomv->handler(atomv, &state);
1982        }
1983        if (*cp) {
1984                sp = cp + strlen(cp);
1985                append_literal(cp, sp, &state);
1986        }
1987        if (need_color_reset_at_eol) {
1988                struct atom_value resetv;
1989                char color[COLOR_MAXLEN] = "";
1990
1991                if (color_parse("reset", color) < 0)
1992                        die("BUG: couldn't parse 'reset' as a color");
1993                resetv.s = color;
1994                append_atom(&resetv, &state);
1995        }
1996        if (state.stack->prev)
1997                die(_("format: %%(end) atom missing"));
1998        strbuf_addbuf(final_buf, &state.stack->output);
1999        pop_stack_element(&state.stack);
2000}
2001
2002void show_ref_array_item(struct ref_array_item *info, const char *format, int quote_style)
2003{
2004        struct strbuf final_buf = STRBUF_INIT;
2005
2006        format_ref_array_item(info, format, quote_style, &final_buf);
2007        fwrite(final_buf.buf, 1, final_buf.len, stdout);
2008        strbuf_release(&final_buf);
2009        putchar('\n');
2010}
2011
2012/*  If no sorting option is given, use refname to sort as default */
2013struct ref_sorting *ref_default_sorting(void)
2014{
2015        static const char cstr_name[] = "refname";
2016
2017        struct ref_sorting *sorting = xcalloc(1, sizeof(*sorting));
2018
2019        sorting->next = NULL;
2020        sorting->atom = parse_ref_filter_atom(cstr_name, cstr_name + strlen(cstr_name));
2021        return sorting;
2022}
2023
2024int parse_opt_ref_sorting(const struct option *opt, const char *arg, int unset)
2025{
2026        struct ref_sorting **sorting_tail = opt->value;
2027        struct ref_sorting *s;
2028        int len;
2029
2030        if (!arg) /* should --no-sort void the list ? */
2031                return -1;
2032
2033        s = xcalloc(1, sizeof(*s));
2034        s->next = *sorting_tail;
2035        *sorting_tail = s;
2036
2037        if (*arg == '-') {
2038                s->reverse = 1;
2039                arg++;
2040        }
2041        if (skip_prefix(arg, "version:", &arg) ||
2042            skip_prefix(arg, "v:", &arg))
2043                s->version = 1;
2044        len = strlen(arg);
2045        s->atom = parse_ref_filter_atom(arg, arg+len);
2046        return 0;
2047}
2048
2049int parse_opt_merge_filter(const struct option *opt, const char *arg, int unset)
2050{
2051        struct ref_filter *rf = opt->value;
2052        unsigned char sha1[20];
2053
2054        rf->merge = starts_with(opt->long_name, "no")
2055                ? REF_FILTER_MERGED_OMIT
2056                : REF_FILTER_MERGED_INCLUDE;
2057
2058        if (get_sha1(arg, sha1))
2059                die(_("malformed object name %s"), arg);
2060
2061        rf->merge_commit = lookup_commit_reference_gently(sha1, 0);
2062        if (!rf->merge_commit)
2063                return opterror(opt, "must point to a commit", 0);
2064
2065        return 0;
2066}