4a05150578d71fc68d0335a41719fe738df2fca9
   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
  19typedef enum { FIELD_STR, FIELD_ULONG, FIELD_TIME } cmp_type;
  20typedef enum { COMPARE_EQUAL, COMPARE_UNEQUAL, COMPARE_NONE } cmp_status;
  21
  22struct align {
  23        align_type position;
  24        unsigned int width;
  25};
  26
  27struct if_then_else {
  28        cmp_status cmp_status;
  29        const char *str;
  30        unsigned int then_atom_seen : 1,
  31                else_atom_seen : 1,
  32                condition_satisfied : 1;
  33};
  34
  35/*
  36 * An atom is a valid field atom listed below, possibly prefixed with
  37 * a "*" to denote deref_tag().
  38 *
  39 * We parse given format string and sort specifiers, and make a list
  40 * of properties that we need to extract out of objects.  ref_array_item
  41 * structure will hold an array of values extracted that can be
  42 * indexed with the "atom number", which is an index into this
  43 * array.
  44 */
  45static struct used_atom {
  46        const char *name;
  47        cmp_type type;
  48        union {
  49                char color[COLOR_MAXLEN];
  50                struct align align;
  51                enum { RR_NORMAL, RR_SHORTEN, RR_TRACK, RR_TRACKSHORT }
  52                        remote_ref;
  53                struct {
  54                        enum { C_BARE, C_BODY, C_BODY_DEP, C_LINES, C_SIG, C_SUB, C_TRAILERS } option;
  55                        unsigned int nlines;
  56                } contents;
  57                struct {
  58                        cmp_status cmp_status;
  59                        const char *str;
  60                } if_then_else;
  61                struct {
  62                        enum { O_FULL, O_LENGTH, O_SHORT } option;
  63                        unsigned int length;
  64                } objectname;
  65        } u;
  66} *used_atom;
  67static int used_atom_cnt, need_tagged, need_symref;
  68static int need_color_reset_at_eol;
  69
  70static void color_atom_parser(struct used_atom *atom, const char *color_value)
  71{
  72        if (!color_value)
  73                die(_("expected format: %%(color:<color>)"));
  74        if (color_parse(color_value, atom->u.color) < 0)
  75                die(_("unrecognized color: %%(color:%s)"), color_value);
  76}
  77
  78static void remote_ref_atom_parser(struct used_atom *atom, const char *arg)
  79{
  80        if (!arg)
  81                atom->u.remote_ref = RR_NORMAL;
  82        else if (!strcmp(arg, "short"))
  83                atom->u.remote_ref = RR_SHORTEN;
  84        else if (!strcmp(arg, "track"))
  85                atom->u.remote_ref = RR_TRACK;
  86        else if (!strcmp(arg, "trackshort"))
  87                atom->u.remote_ref = RR_TRACKSHORT;
  88        else
  89                die(_("unrecognized format: %%(%s)"), atom->name);
  90}
  91
  92static void body_atom_parser(struct used_atom *atom, const char *arg)
  93{
  94        if (arg)
  95                die(_("%%(body) does not take arguments"));
  96        atom->u.contents.option = C_BODY_DEP;
  97}
  98
  99static void subject_atom_parser(struct used_atom *atom, const char *arg)
 100{
 101        if (arg)
 102                die(_("%%(subject) does not take arguments"));
 103        atom->u.contents.option = C_SUB;
 104}
 105
 106static void trailers_atom_parser(struct used_atom *atom, const char *arg)
 107{
 108        if (arg)
 109                die(_("%%(trailers) does not take arguments"));
 110        atom->u.contents.option = C_TRAILERS;
 111}
 112
 113static void contents_atom_parser(struct used_atom *atom, const char *arg)
 114{
 115        if (!arg)
 116                atom->u.contents.option = C_BARE;
 117        else if (!strcmp(arg, "body"))
 118                atom->u.contents.option = C_BODY;
 119        else if (!strcmp(arg, "signature"))
 120                atom->u.contents.option = C_SIG;
 121        else if (!strcmp(arg, "subject"))
 122                atom->u.contents.option = C_SUB;
 123        else if (!strcmp(arg, "trailers"))
 124                atom->u.contents.option = C_TRAILERS;
 125        else if (skip_prefix(arg, "lines=", &arg)) {
 126                atom->u.contents.option = C_LINES;
 127                if (strtoul_ui(arg, 10, &atom->u.contents.nlines))
 128                        die(_("positive value expected contents:lines=%s"), arg);
 129        } else
 130                die(_("unrecognized %%(contents) argument: %s"), arg);
 131}
 132
 133static void objectname_atom_parser(struct used_atom *atom, const char *arg)
 134{
 135        if (!arg)
 136                atom->u.objectname.option = O_FULL;
 137        else if (!strcmp(arg, "short"))
 138                atom->u.objectname.option = O_SHORT;
 139        else if (skip_prefix(arg, "short=", &arg)) {
 140                atom->u.objectname.option = O_LENGTH;
 141                if (strtoul_ui(arg, 10, &atom->u.objectname.length) ||
 142                    atom->u.objectname.length == 0)
 143                        die(_("positive value expected objectname:short=%s"), arg);
 144                if (atom->u.objectname.length < MINIMUM_ABBREV)
 145                        atom->u.objectname.length = MINIMUM_ABBREV;
 146        } else
 147                die(_("unrecognized %%(objectname) argument: %s"), arg);
 148}
 149
 150static align_type parse_align_position(const char *s)
 151{
 152        if (!strcmp(s, "right"))
 153                return ALIGN_RIGHT;
 154        else if (!strcmp(s, "middle"))
 155                return ALIGN_MIDDLE;
 156        else if (!strcmp(s, "left"))
 157                return ALIGN_LEFT;
 158        return -1;
 159}
 160
 161static void align_atom_parser(struct used_atom *atom, const char *arg)
 162{
 163        struct align *align = &atom->u.align;
 164        struct string_list params = STRING_LIST_INIT_DUP;
 165        int i;
 166        unsigned int width = ~0U;
 167
 168        if (!arg)
 169                die(_("expected format: %%(align:<width>,<position>)"));
 170
 171        align->position = ALIGN_LEFT;
 172
 173        string_list_split(&params, arg, ',', -1);
 174        for (i = 0; i < params.nr; i++) {
 175                const char *s = params.items[i].string;
 176                int position;
 177
 178                if (skip_prefix(s, "position=", &s)) {
 179                        position = parse_align_position(s);
 180                        if (position < 0)
 181                                die(_("unrecognized position:%s"), s);
 182                        align->position = position;
 183                } else if (skip_prefix(s, "width=", &s)) {
 184                        if (strtoul_ui(s, 10, &width))
 185                                die(_("unrecognized width:%s"), s);
 186                } else if (!strtoul_ui(s, 10, &width))
 187                        ;
 188                else if ((position = parse_align_position(s)) >= 0)
 189                        align->position = position;
 190                else
 191                        die(_("unrecognized %%(align) argument: %s"), s);
 192        }
 193
 194        if (width == ~0U)
 195                die(_("positive width expected with the %%(align) atom"));
 196        align->width = width;
 197        string_list_clear(&params, 0);
 198}
 199
 200static void if_atom_parser(struct used_atom *atom, const char *arg)
 201{
 202        if (!arg) {
 203                atom->u.if_then_else.cmp_status = COMPARE_NONE;
 204                return;
 205        } else if (skip_prefix(arg, "equals=", &atom->u.if_then_else.str)) {
 206                atom->u.if_then_else.cmp_status = COMPARE_EQUAL;
 207        } else if (skip_prefix(arg, "notequals=", &atom->u.if_then_else.str)) {
 208                atom->u.if_then_else.cmp_status = COMPARE_UNEQUAL;
 209        } else {
 210                die(_("unrecognized %%(if) argument: %s"), arg);
 211        }
 212}
 213
 214
 215static struct {
 216        const char *name;
 217        cmp_type cmp_type;
 218        void (*parser)(struct used_atom *atom, const char *arg);
 219} valid_atom[] = {
 220        { "refname" },
 221        { "objecttype" },
 222        { "objectsize", FIELD_ULONG },
 223        { "objectname", FIELD_STR, objectname_atom_parser },
 224        { "tree" },
 225        { "parent" },
 226        { "numparent", FIELD_ULONG },
 227        { "object" },
 228        { "type" },
 229        { "tag" },
 230        { "author" },
 231        { "authorname" },
 232        { "authoremail" },
 233        { "authordate", FIELD_TIME },
 234        { "committer" },
 235        { "committername" },
 236        { "committeremail" },
 237        { "committerdate", FIELD_TIME },
 238        { "tagger" },
 239        { "taggername" },
 240        { "taggeremail" },
 241        { "taggerdate", FIELD_TIME },
 242        { "creator" },
 243        { "creatordate", FIELD_TIME },
 244        { "subject", FIELD_STR, subject_atom_parser },
 245        { "body", FIELD_STR, body_atom_parser },
 246        { "trailers", FIELD_STR, trailers_atom_parser },
 247        { "contents", FIELD_STR, contents_atom_parser },
 248        { "upstream", FIELD_STR, remote_ref_atom_parser },
 249        { "push", FIELD_STR, remote_ref_atom_parser },
 250        { "symref" },
 251        { "flag" },
 252        { "HEAD" },
 253        { "color", FIELD_STR, color_atom_parser },
 254        { "align", FIELD_STR, align_atom_parser },
 255        { "end" },
 256        { "if", FIELD_STR, if_atom_parser },
 257        { "then" },
 258        { "else" },
 259};
 260
 261#define REF_FORMATTING_STATE_INIT  { 0, NULL }
 262
 263struct ref_formatting_stack {
 264        struct ref_formatting_stack *prev;
 265        struct strbuf output;
 266        void (*at_end)(struct ref_formatting_stack **stack);
 267        void *at_end_data;
 268};
 269
 270struct ref_formatting_state {
 271        int quote_style;
 272        struct ref_formatting_stack *stack;
 273};
 274
 275struct atom_value {
 276        const char *s;
 277        void (*handler)(struct atom_value *atomv, struct ref_formatting_state *state);
 278        unsigned long ul; /* used for sorting when not FIELD_STR */
 279        struct used_atom *atom;
 280};
 281
 282/*
 283 * Used to parse format string and sort specifiers
 284 */
 285int parse_ref_filter_atom(const char *atom, const char *ep)
 286{
 287        const char *sp;
 288        const char *arg;
 289        int i, at, atom_len;
 290
 291        sp = atom;
 292        if (*sp == '*' && sp < ep)
 293                sp++; /* deref */
 294        if (ep <= sp)
 295                die(_("malformed field name: %.*s"), (int)(ep-atom), atom);
 296
 297        /* Do we have the atom already used elsewhere? */
 298        for (i = 0; i < used_atom_cnt; i++) {
 299                int len = strlen(used_atom[i].name);
 300                if (len == ep - atom && !memcmp(used_atom[i].name, atom, len))
 301                        return i;
 302        }
 303
 304        /*
 305         * If the atom name has a colon, strip it and everything after
 306         * it off - it specifies the format for this entry, and
 307         * shouldn't be used for checking against the valid_atom
 308         * table.
 309         */
 310        arg = memchr(sp, ':', ep - sp);
 311        atom_len = (arg ? arg : ep) - sp;
 312
 313        /* Is the atom a valid one? */
 314        for (i = 0; i < ARRAY_SIZE(valid_atom); i++) {
 315                int len = strlen(valid_atom[i].name);
 316                if (len == atom_len && !memcmp(valid_atom[i].name, sp, len))
 317                        break;
 318        }
 319
 320        if (ARRAY_SIZE(valid_atom) <= i)
 321                die(_("unknown field name: %.*s"), (int)(ep-atom), atom);
 322
 323        /* Add it in, including the deref prefix */
 324        at = used_atom_cnt;
 325        used_atom_cnt++;
 326        REALLOC_ARRAY(used_atom, used_atom_cnt);
 327        used_atom[at].name = xmemdupz(atom, ep - atom);
 328        used_atom[at].type = valid_atom[i].cmp_type;
 329        if (arg)
 330                arg = used_atom[at].name + (arg - atom) + 1;
 331        memset(&used_atom[at].u, 0, sizeof(used_atom[at].u));
 332        if (valid_atom[i].parser)
 333                valid_atom[i].parser(&used_atom[at], arg);
 334        if (*atom == '*')
 335                need_tagged = 1;
 336        if (!strcmp(used_atom[at].name, "symref"))
 337                need_symref = 1;
 338        return at;
 339}
 340
 341static void quote_formatting(struct strbuf *s, const char *str, int quote_style)
 342{
 343        switch (quote_style) {
 344        case QUOTE_NONE:
 345                strbuf_addstr(s, str);
 346                break;
 347        case QUOTE_SHELL:
 348                sq_quote_buf(s, str);
 349                break;
 350        case QUOTE_PERL:
 351                perl_quote_buf(s, str);
 352                break;
 353        case QUOTE_PYTHON:
 354                python_quote_buf(s, str);
 355                break;
 356        case QUOTE_TCL:
 357                tcl_quote_buf(s, str);
 358                break;
 359        }
 360}
 361
 362static void append_atom(struct atom_value *v, struct ref_formatting_state *state)
 363{
 364        /*
 365         * Quote formatting is only done when the stack has a single
 366         * element. Otherwise quote formatting is done on the
 367         * element's entire output strbuf when the %(end) atom is
 368         * encountered.
 369         */
 370        if (!state->stack->prev)
 371                quote_formatting(&state->stack->output, v->s, state->quote_style);
 372        else
 373                strbuf_addstr(&state->stack->output, v->s);
 374}
 375
 376static void push_stack_element(struct ref_formatting_stack **stack)
 377{
 378        struct ref_formatting_stack *s = xcalloc(1, sizeof(struct ref_formatting_stack));
 379
 380        strbuf_init(&s->output, 0);
 381        s->prev = *stack;
 382        *stack = s;
 383}
 384
 385static void pop_stack_element(struct ref_formatting_stack **stack)
 386{
 387        struct ref_formatting_stack *current = *stack;
 388        struct ref_formatting_stack *prev = current->prev;
 389
 390        if (prev)
 391                strbuf_addbuf(&prev->output, &current->output);
 392        strbuf_release(&current->output);
 393        free(current);
 394        *stack = prev;
 395}
 396
 397static void end_align_handler(struct ref_formatting_stack **stack)
 398{
 399        struct ref_formatting_stack *cur = *stack;
 400        struct align *align = (struct align *)cur->at_end_data;
 401        struct strbuf s = STRBUF_INIT;
 402
 403        strbuf_utf8_align(&s, align->position, align->width, cur->output.buf);
 404        strbuf_swap(&cur->output, &s);
 405        strbuf_release(&s);
 406}
 407
 408static void align_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
 409{
 410        struct ref_formatting_stack *new;
 411
 412        push_stack_element(&state->stack);
 413        new = state->stack;
 414        new->at_end = end_align_handler;
 415        new->at_end_data = &atomv->atom->u.align;
 416}
 417
 418static void if_then_else_handler(struct ref_formatting_stack **stack)
 419{
 420        struct ref_formatting_stack *cur = *stack;
 421        struct ref_formatting_stack *prev = cur->prev;
 422        struct if_then_else *if_then_else = (struct if_then_else *)cur->at_end_data;
 423
 424        if (!if_then_else->then_atom_seen)
 425                die(_("format: %%(if) atom used without a %%(then) atom"));
 426
 427        if (if_then_else->else_atom_seen) {
 428                /*
 429                 * There is an %(else) atom: we need to drop one state from the
 430                 * stack, either the %(else) branch if the condition is satisfied, or
 431                 * the %(then) branch if it isn't.
 432                 */
 433                if (if_then_else->condition_satisfied) {
 434                        strbuf_reset(&cur->output);
 435                        pop_stack_element(&cur);
 436                } else {
 437                        strbuf_swap(&cur->output, &prev->output);
 438                        strbuf_reset(&cur->output);
 439                        pop_stack_element(&cur);
 440                }
 441        } else if (!if_then_else->condition_satisfied) {
 442                /*
 443                 * No %(else) atom: just drop the %(then) branch if the
 444                 * condition is not satisfied.
 445                 */
 446                strbuf_reset(&cur->output);
 447        }
 448
 449        *stack = cur;
 450        free(if_then_else);
 451}
 452
 453static void if_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
 454{
 455        struct ref_formatting_stack *new;
 456        struct if_then_else *if_then_else = xcalloc(sizeof(struct if_then_else), 1);
 457
 458        if_then_else->str = atomv->atom->u.if_then_else.str;
 459        if_then_else->cmp_status = atomv->atom->u.if_then_else.cmp_status;
 460
 461        push_stack_element(&state->stack);
 462        new = state->stack;
 463        new->at_end = if_then_else_handler;
 464        new->at_end_data = if_then_else;
 465}
 466
 467static int is_empty(const char *s)
 468{
 469        while (*s != '\0') {
 470                if (!isspace(*s))
 471                        return 0;
 472                s++;
 473        }
 474        return 1;
 475}
 476
 477static void then_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
 478{
 479        struct ref_formatting_stack *cur = state->stack;
 480        struct if_then_else *if_then_else = NULL;
 481
 482        if (cur->at_end == if_then_else_handler)
 483                if_then_else = (struct if_then_else *)cur->at_end_data;
 484        if (!if_then_else)
 485                die(_("format: %%(then) atom used without an %%(if) atom"));
 486        if (if_then_else->then_atom_seen)
 487                die(_("format: %%(then) atom used more than once"));
 488        if (if_then_else->else_atom_seen)
 489                die(_("format: %%(then) atom used after %%(else)"));
 490        if_then_else->then_atom_seen = 1;
 491        /*
 492         * If the 'equals' or 'notequals' attribute is used then
 493         * perform the required comparison. If not, only non-empty
 494         * strings satisfy the 'if' condition.
 495         */
 496        if (if_then_else->cmp_status == COMPARE_EQUAL) {
 497                if (!strcmp(if_then_else->str, cur->output.buf))
 498                        if_then_else->condition_satisfied = 1;
 499        } else if (if_then_else->cmp_status == COMPARE_UNEQUAL) {
 500                if (strcmp(if_then_else->str, cur->output.buf))
 501                        if_then_else->condition_satisfied = 1;
 502        } else if (cur->output.len && !is_empty(cur->output.buf))
 503                if_then_else->condition_satisfied = 1;
 504        strbuf_reset(&cur->output);
 505}
 506
 507static void else_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
 508{
 509        struct ref_formatting_stack *prev = state->stack;
 510        struct if_then_else *if_then_else = NULL;
 511
 512        if (prev->at_end == if_then_else_handler)
 513                if_then_else = (struct if_then_else *)prev->at_end_data;
 514        if (!if_then_else)
 515                die(_("format: %%(else) atom used without an %%(if) atom"));
 516        if (!if_then_else->then_atom_seen)
 517                die(_("format: %%(else) atom used without a %%(then) atom"));
 518        if (if_then_else->else_atom_seen)
 519                die(_("format: %%(else) atom used more than once"));
 520        if_then_else->else_atom_seen = 1;
 521        push_stack_element(&state->stack);
 522        state->stack->at_end_data = prev->at_end_data;
 523        state->stack->at_end = prev->at_end;
 524}
 525
 526static void end_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
 527{
 528        struct ref_formatting_stack *current = state->stack;
 529        struct strbuf s = STRBUF_INIT;
 530
 531        if (!current->at_end)
 532                die(_("format: %%(end) atom used without corresponding atom"));
 533        current->at_end(&state->stack);
 534
 535        /*  Stack may have been popped within at_end(), hence reset the current pointer */
 536        current = state->stack;
 537
 538        /*
 539         * Perform quote formatting when the stack element is that of
 540         * a supporting atom. If nested then perform quote formatting
 541         * only on the topmost supporting atom.
 542         */
 543        if (!current->prev->prev) {
 544                quote_formatting(&s, current->output.buf, state->quote_style);
 545                strbuf_swap(&current->output, &s);
 546        }
 547        strbuf_release(&s);
 548        pop_stack_element(&state->stack);
 549}
 550
 551/*
 552 * In a format string, find the next occurrence of %(atom).
 553 */
 554static const char *find_next(const char *cp)
 555{
 556        while (*cp) {
 557                if (*cp == '%') {
 558                        /*
 559                         * %( is the start of an atom;
 560                         * %% is a quoted per-cent.
 561                         */
 562                        if (cp[1] == '(')
 563                                return cp;
 564                        else if (cp[1] == '%')
 565                                cp++; /* skip over two % */
 566                        /* otherwise this is a singleton, literal % */
 567                }
 568                cp++;
 569        }
 570        return NULL;
 571}
 572
 573/*
 574 * Make sure the format string is well formed, and parse out
 575 * the used atoms.
 576 */
 577int verify_ref_format(const char *format)
 578{
 579        const char *cp, *sp;
 580
 581        need_color_reset_at_eol = 0;
 582        for (cp = format; *cp && (sp = find_next(cp)); ) {
 583                const char *color, *ep = strchr(sp, ')');
 584                int at;
 585
 586                if (!ep)
 587                        return error(_("malformed format string %s"), sp);
 588                /* sp points at "%(" and ep points at the closing ")" */
 589                at = parse_ref_filter_atom(sp + 2, ep);
 590                cp = ep + 1;
 591
 592                if (skip_prefix(used_atom[at].name, "color:", &color))
 593                        need_color_reset_at_eol = !!strcmp(color, "reset");
 594        }
 595        return 0;
 596}
 597
 598/*
 599 * Given an object name, read the object data and size, and return a
 600 * "struct object".  If the object data we are returning is also borrowed
 601 * by the "struct object" representation, set *eaten as well---it is a
 602 * signal from parse_object_buffer to us not to free the buffer.
 603 */
 604static void *get_obj(const unsigned char *sha1, struct object **obj, unsigned long *sz, int *eaten)
 605{
 606        enum object_type type;
 607        void *buf = read_sha1_file(sha1, &type, sz);
 608
 609        if (buf)
 610                *obj = parse_object_buffer(sha1, type, *sz, buf, eaten);
 611        else
 612                *obj = NULL;
 613        return buf;
 614}
 615
 616static int grab_objectname(const char *name, const unsigned char *sha1,
 617                           struct atom_value *v, struct used_atom *atom)
 618{
 619        if (starts_with(name, "objectname")) {
 620                if (atom->u.objectname.option == O_SHORT) {
 621                        v->s = xstrdup(find_unique_abbrev(sha1, DEFAULT_ABBREV));
 622                        return 1;
 623                } else if (atom->u.objectname.option == O_FULL) {
 624                        v->s = xstrdup(sha1_to_hex(sha1));
 625                        return 1;
 626                } else if (atom->u.objectname.option == O_LENGTH) {
 627                        v->s = xstrdup(find_unique_abbrev(sha1, atom->u.objectname.length));
 628                        return 1;
 629                } else
 630                        die("BUG: unknown %%(objectname) option");
 631        }
 632        return 0;
 633}
 634
 635/* See grab_values */
 636static void grab_common_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 637{
 638        int i;
 639
 640        for (i = 0; i < used_atom_cnt; i++) {
 641                const char *name = used_atom[i].name;
 642                struct atom_value *v = &val[i];
 643                if (!!deref != (*name == '*'))
 644                        continue;
 645                if (deref)
 646                        name++;
 647                if (!strcmp(name, "objecttype"))
 648                        v->s = typename(obj->type);
 649                else if (!strcmp(name, "objectsize")) {
 650                        v->ul = sz;
 651                        v->s = xstrfmt("%lu", sz);
 652                }
 653                else if (deref)
 654                        grab_objectname(name, obj->oid.hash, v, &used_atom[i]);
 655        }
 656}
 657
 658/* See grab_values */
 659static void grab_tag_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 660{
 661        int i;
 662        struct tag *tag = (struct tag *) obj;
 663
 664        for (i = 0; i < used_atom_cnt; i++) {
 665                const char *name = used_atom[i].name;
 666                struct atom_value *v = &val[i];
 667                if (!!deref != (*name == '*'))
 668                        continue;
 669                if (deref)
 670                        name++;
 671                if (!strcmp(name, "tag"))
 672                        v->s = tag->tag;
 673                else if (!strcmp(name, "type") && tag->tagged)
 674                        v->s = typename(tag->tagged->type);
 675                else if (!strcmp(name, "object") && tag->tagged)
 676                        v->s = xstrdup(oid_to_hex(&tag->tagged->oid));
 677        }
 678}
 679
 680/* See grab_values */
 681static void grab_commit_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 682{
 683        int i;
 684        struct commit *commit = (struct commit *) obj;
 685
 686        for (i = 0; i < used_atom_cnt; i++) {
 687                const char *name = used_atom[i].name;
 688                struct atom_value *v = &val[i];
 689                if (!!deref != (*name == '*'))
 690                        continue;
 691                if (deref)
 692                        name++;
 693                if (!strcmp(name, "tree")) {
 694                        v->s = xstrdup(oid_to_hex(&commit->tree->object.oid));
 695                }
 696                else if (!strcmp(name, "numparent")) {
 697                        v->ul = commit_list_count(commit->parents);
 698                        v->s = xstrfmt("%lu", v->ul);
 699                }
 700                else if (!strcmp(name, "parent")) {
 701                        struct commit_list *parents;
 702                        struct strbuf s = STRBUF_INIT;
 703                        for (parents = commit->parents; parents; parents = parents->next) {
 704                                struct commit *parent = parents->item;
 705                                if (parents != commit->parents)
 706                                        strbuf_addch(&s, ' ');
 707                                strbuf_addstr(&s, oid_to_hex(&parent->object.oid));
 708                        }
 709                        v->s = strbuf_detach(&s, NULL);
 710                }
 711        }
 712}
 713
 714static const char *find_wholine(const char *who, int wholen, const char *buf, unsigned long sz)
 715{
 716        const char *eol;
 717        while (*buf) {
 718                if (!strncmp(buf, who, wholen) &&
 719                    buf[wholen] == ' ')
 720                        return buf + wholen + 1;
 721                eol = strchr(buf, '\n');
 722                if (!eol)
 723                        return "";
 724                eol++;
 725                if (*eol == '\n')
 726                        return ""; /* end of header */
 727                buf = eol;
 728        }
 729        return "";
 730}
 731
 732static const char *copy_line(const char *buf)
 733{
 734        const char *eol = strchrnul(buf, '\n');
 735        return xmemdupz(buf, eol - buf);
 736}
 737
 738static const char *copy_name(const char *buf)
 739{
 740        const char *cp;
 741        for (cp = buf; *cp && *cp != '\n'; cp++) {
 742                if (!strncmp(cp, " <", 2))
 743                        return xmemdupz(buf, cp - buf);
 744        }
 745        return "";
 746}
 747
 748static const char *copy_email(const char *buf)
 749{
 750        const char *email = strchr(buf, '<');
 751        const char *eoemail;
 752        if (!email)
 753                return "";
 754        eoemail = strchr(email, '>');
 755        if (!eoemail)
 756                return "";
 757        return xmemdupz(email, eoemail + 1 - email);
 758}
 759
 760static char *copy_subject(const char *buf, unsigned long len)
 761{
 762        char *r = xmemdupz(buf, len);
 763        int i;
 764
 765        for (i = 0; i < len; i++)
 766                if (r[i] == '\n')
 767                        r[i] = ' ';
 768
 769        return r;
 770}
 771
 772static void grab_date(const char *buf, struct atom_value *v, const char *atomname)
 773{
 774        const char *eoemail = strstr(buf, "> ");
 775        char *zone;
 776        unsigned long timestamp;
 777        long tz;
 778        struct date_mode date_mode = { DATE_NORMAL };
 779        const char *formatp;
 780
 781        /*
 782         * We got here because atomname ends in "date" or "date<something>";
 783         * it's not possible that <something> is not ":<format>" because
 784         * parse_ref_filter_atom() wouldn't have allowed it, so we can assume that no
 785         * ":" means no format is specified, and use the default.
 786         */
 787        formatp = strchr(atomname, ':');
 788        if (formatp != NULL) {
 789                formatp++;
 790                parse_date_format(formatp, &date_mode);
 791        }
 792
 793        if (!eoemail)
 794                goto bad;
 795        timestamp = strtoul(eoemail + 2, &zone, 10);
 796        if (timestamp == ULONG_MAX)
 797                goto bad;
 798        tz = strtol(zone, NULL, 10);
 799        if ((tz == LONG_MIN || tz == LONG_MAX) && errno == ERANGE)
 800                goto bad;
 801        v->s = xstrdup(show_date(timestamp, tz, &date_mode));
 802        v->ul = timestamp;
 803        return;
 804 bad:
 805        v->s = "";
 806        v->ul = 0;
 807}
 808
 809/* See grab_values */
 810static void grab_person(const char *who, struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 811{
 812        int i;
 813        int wholen = strlen(who);
 814        const char *wholine = NULL;
 815
 816        for (i = 0; i < used_atom_cnt; i++) {
 817                const char *name = used_atom[i].name;
 818                struct atom_value *v = &val[i];
 819                if (!!deref != (*name == '*'))
 820                        continue;
 821                if (deref)
 822                        name++;
 823                if (strncmp(who, name, wholen))
 824                        continue;
 825                if (name[wholen] != 0 &&
 826                    strcmp(name + wholen, "name") &&
 827                    strcmp(name + wholen, "email") &&
 828                    !starts_with(name + wholen, "date"))
 829                        continue;
 830                if (!wholine)
 831                        wholine = find_wholine(who, wholen, buf, sz);
 832                if (!wholine)
 833                        return; /* no point looking for it */
 834                if (name[wholen] == 0)
 835                        v->s = copy_line(wholine);
 836                else if (!strcmp(name + wholen, "name"))
 837                        v->s = copy_name(wholine);
 838                else if (!strcmp(name + wholen, "email"))
 839                        v->s = copy_email(wholine);
 840                else if (starts_with(name + wholen, "date"))
 841                        grab_date(wholine, v, name);
 842        }
 843
 844        /*
 845         * For a tag or a commit object, if "creator" or "creatordate" is
 846         * requested, do something special.
 847         */
 848        if (strcmp(who, "tagger") && strcmp(who, "committer"))
 849                return; /* "author" for commit object is not wanted */
 850        if (!wholine)
 851                wholine = find_wholine(who, wholen, buf, sz);
 852        if (!wholine)
 853                return;
 854        for (i = 0; i < used_atom_cnt; i++) {
 855                const char *name = used_atom[i].name;
 856                struct atom_value *v = &val[i];
 857                if (!!deref != (*name == '*'))
 858                        continue;
 859                if (deref)
 860                        name++;
 861
 862                if (starts_with(name, "creatordate"))
 863                        grab_date(wholine, v, name);
 864                else if (!strcmp(name, "creator"))
 865                        v->s = copy_line(wholine);
 866        }
 867}
 868
 869static void find_subpos(const char *buf, unsigned long sz,
 870                        const char **sub, unsigned long *sublen,
 871                        const char **body, unsigned long *bodylen,
 872                        unsigned long *nonsiglen,
 873                        const char **sig, unsigned long *siglen)
 874{
 875        const char *eol;
 876        /* skip past header until we hit empty line */
 877        while (*buf && *buf != '\n') {
 878                eol = strchrnul(buf, '\n');
 879                if (*eol)
 880                        eol++;
 881                buf = eol;
 882        }
 883        /* skip any empty lines */
 884        while (*buf == '\n')
 885                buf++;
 886
 887        /* parse signature first; we might not even have a subject line */
 888        *sig = buf + parse_signature(buf, strlen(buf));
 889        *siglen = strlen(*sig);
 890
 891        /* subject is first non-empty line */
 892        *sub = buf;
 893        /* subject goes to first empty line */
 894        while (buf < *sig && *buf && *buf != '\n') {
 895                eol = strchrnul(buf, '\n');
 896                if (*eol)
 897                        eol++;
 898                buf = eol;
 899        }
 900        *sublen = buf - *sub;
 901        /* drop trailing newline, if present */
 902        if (*sublen && (*sub)[*sublen - 1] == '\n')
 903                *sublen -= 1;
 904
 905        /* skip any empty lines */
 906        while (*buf == '\n')
 907                buf++;
 908        *body = buf;
 909        *bodylen = strlen(buf);
 910        *nonsiglen = *sig - buf;
 911}
 912
 913/*
 914 * If 'lines' is greater than 0, append that many lines from the given
 915 * 'buf' of length 'size' to the given strbuf.
 916 */
 917static void append_lines(struct strbuf *out, const char *buf, unsigned long size, int lines)
 918{
 919        int i;
 920        const char *sp, *eol;
 921        size_t len;
 922
 923        sp = buf;
 924
 925        for (i = 0; i < lines && sp < buf + size; i++) {
 926                if (i)
 927                        strbuf_addstr(out, "\n    ");
 928                eol = memchr(sp, '\n', size - (sp - buf));
 929                len = eol ? eol - sp : size - (sp - buf);
 930                strbuf_add(out, sp, len);
 931                if (!eol)
 932                        break;
 933                sp = eol + 1;
 934        }
 935}
 936
 937/* See grab_values */
 938static void grab_sub_body_contents(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 939{
 940        int i;
 941        const char *subpos = NULL, *bodypos = NULL, *sigpos = NULL;
 942        unsigned long sublen = 0, bodylen = 0, nonsiglen = 0, siglen = 0;
 943
 944        for (i = 0; i < used_atom_cnt; i++) {
 945                struct used_atom *atom = &used_atom[i];
 946                const char *name = atom->name;
 947                struct atom_value *v = &val[i];
 948                if (!!deref != (*name == '*'))
 949                        continue;
 950                if (deref)
 951                        name++;
 952                if (strcmp(name, "subject") &&
 953                    strcmp(name, "body") &&
 954                    strcmp(name, "trailers") &&
 955                    !starts_with(name, "contents"))
 956                        continue;
 957                if (!subpos)
 958                        find_subpos(buf, sz,
 959                                    &subpos, &sublen,
 960                                    &bodypos, &bodylen, &nonsiglen,
 961                                    &sigpos, &siglen);
 962
 963                if (atom->u.contents.option == C_SUB)
 964                        v->s = copy_subject(subpos, sublen);
 965                else if (atom->u.contents.option == C_BODY_DEP)
 966                        v->s = xmemdupz(bodypos, bodylen);
 967                else if (atom->u.contents.option == C_BODY)
 968                        v->s = xmemdupz(bodypos, nonsiglen);
 969                else if (atom->u.contents.option == C_SIG)
 970                        v->s = xmemdupz(sigpos, siglen);
 971                else if (atom->u.contents.option == C_LINES) {
 972                        struct strbuf s = STRBUF_INIT;
 973                        const char *contents_end = bodylen + bodypos - siglen;
 974
 975                        /*  Size is the length of the message after removing the signature */
 976                        append_lines(&s, subpos, contents_end - subpos, atom->u.contents.nlines);
 977                        v->s = strbuf_detach(&s, NULL);
 978                } else if (atom->u.contents.option == C_TRAILERS) {
 979                        struct trailer_info info;
 980
 981                        /* Search for trailer info */
 982                        trailer_info_get(&info, subpos);
 983                        v->s = xmemdupz(info.trailer_start,
 984                                        info.trailer_end - info.trailer_start);
 985                        trailer_info_release(&info);
 986                } else if (atom->u.contents.option == C_BARE)
 987                        v->s = xstrdup(subpos);
 988        }
 989}
 990
 991/*
 992 * We want to have empty print-string for field requests
 993 * that do not apply (e.g. "authordate" for a tag object)
 994 */
 995static void fill_missing_values(struct atom_value *val)
 996{
 997        int i;
 998        for (i = 0; i < used_atom_cnt; i++) {
 999                struct atom_value *v = &val[i];
1000                if (v->s == NULL)
1001                        v->s = "";
1002        }
1003}
1004
1005/*
1006 * val is a list of atom_value to hold returned values.  Extract
1007 * the values for atoms in used_atom array out of (obj, buf, sz).
1008 * when deref is false, (obj, buf, sz) is the object that is
1009 * pointed at by the ref itself; otherwise it is the object the
1010 * ref (which is a tag) refers to.
1011 */
1012static void grab_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
1013{
1014        grab_common_values(val, deref, obj, buf, sz);
1015        switch (obj->type) {
1016        case OBJ_TAG:
1017                grab_tag_values(val, deref, obj, buf, sz);
1018                grab_sub_body_contents(val, deref, obj, buf, sz);
1019                grab_person("tagger", val, deref, obj, buf, sz);
1020                break;
1021        case OBJ_COMMIT:
1022                grab_commit_values(val, deref, obj, buf, sz);
1023                grab_sub_body_contents(val, deref, obj, buf, sz);
1024                grab_person("author", val, deref, obj, buf, sz);
1025                grab_person("committer", val, deref, obj, buf, sz);
1026                break;
1027        case OBJ_TREE:
1028                /* grab_tree_values(val, deref, obj, buf, sz); */
1029                break;
1030        case OBJ_BLOB:
1031                /* grab_blob_values(val, deref, obj, buf, sz); */
1032                break;
1033        default:
1034                die("Eh?  Object of type %d?", obj->type);
1035        }
1036}
1037
1038static inline char *copy_advance(char *dst, const char *src)
1039{
1040        while (*src)
1041                *dst++ = *src++;
1042        return dst;
1043}
1044
1045static const char *strip_ref_components(const char *refname, const char *nr_arg)
1046{
1047        char *end;
1048        long nr = strtol(nr_arg, &end, 10);
1049        long remaining = nr;
1050        const char *start = refname;
1051
1052        if (nr < 1 || *end != '\0')
1053                die(_(":strip= requires a positive integer argument"));
1054
1055        while (remaining) {
1056                switch (*start++) {
1057                case '\0':
1058                        die(_("ref '%s' does not have %ld components to :strip"),
1059                            refname, nr);
1060                case '/':
1061                        remaining--;
1062                        break;
1063                }
1064        }
1065        return start;
1066}
1067
1068static void fill_remote_ref_details(struct used_atom *atom, const char *refname,
1069                                    struct branch *branch, const char **s)
1070{
1071        int num_ours, num_theirs;
1072        if (atom->u.remote_ref == RR_SHORTEN)
1073                *s = shorten_unambiguous_ref(refname, warn_ambiguous_refs);
1074        else if (atom->u.remote_ref == RR_TRACK) {
1075                if (stat_tracking_info(branch, &num_ours,
1076                                       &num_theirs, NULL)) {
1077                        *s = "[gone]";
1078                        return;
1079                }
1080
1081                if (!num_ours && !num_theirs)
1082                        *s = "";
1083                else if (!num_ours)
1084                        *s = xstrfmt("[behind %d]", num_theirs);
1085                else if (!num_theirs)
1086                        *s = xstrfmt("[ahead %d]", num_ours);
1087                else
1088                        *s = xstrfmt("[ahead %d, behind %d]",
1089                                     num_ours, num_theirs);
1090        } else if (atom->u.remote_ref == RR_TRACKSHORT) {
1091                if (stat_tracking_info(branch, &num_ours,
1092                                       &num_theirs, NULL))
1093                        return;
1094
1095                if (!num_ours && !num_theirs)
1096                        *s = "=";
1097                else if (!num_ours)
1098                        *s = "<";
1099                else if (!num_theirs)
1100                        *s = ">";
1101                else
1102                        *s = "<>";
1103        } else /* RR_NORMAL */
1104                *s = refname;
1105}
1106
1107char *get_head_description(void)
1108{
1109        struct strbuf desc = STRBUF_INIT;
1110        struct wt_status_state state;
1111        memset(&state, 0, sizeof(state));
1112        wt_status_get_state(&state, 1);
1113        if (state.rebase_in_progress ||
1114            state.rebase_interactive_in_progress)
1115                strbuf_addf(&desc, _("(no branch, rebasing %s)"),
1116                            state.branch);
1117        else if (state.bisect_in_progress)
1118                strbuf_addf(&desc, _("(no branch, bisect started on %s)"),
1119                            state.branch);
1120        else if (state.detached_from) {
1121                /* TRANSLATORS: make sure these match _("HEAD detached at ")
1122                   and _("HEAD detached from ") in wt-status.c */
1123                if (state.detached_at)
1124                        strbuf_addf(&desc, _("(HEAD detached at %s)"),
1125                                state.detached_from);
1126                else
1127                        strbuf_addf(&desc, _("(HEAD detached from %s)"),
1128                                state.detached_from);
1129        }
1130        else
1131                strbuf_addstr(&desc, _("(no branch)"));
1132        free(state.branch);
1133        free(state.onto);
1134        free(state.detached_from);
1135        return strbuf_detach(&desc, NULL);
1136}
1137
1138/*
1139 * Parse the object referred by ref, and grab needed value.
1140 */
1141static void populate_value(struct ref_array_item *ref)
1142{
1143        void *buf;
1144        struct object *obj;
1145        int eaten, i;
1146        unsigned long size;
1147        const unsigned char *tagged;
1148
1149        ref->value = xcalloc(used_atom_cnt, sizeof(struct atom_value));
1150
1151        if (need_symref && (ref->flag & REF_ISSYMREF) && !ref->symref) {
1152                unsigned char unused1[20];
1153                ref->symref = resolve_refdup(ref->refname, RESOLVE_REF_READING,
1154                                             unused1, NULL);
1155                if (!ref->symref)
1156                        ref->symref = "";
1157        }
1158
1159        /* Fill in specials first */
1160        for (i = 0; i < used_atom_cnt; i++) {
1161                struct used_atom *atom = &used_atom[i];
1162                const char *name = used_atom[i].name;
1163                struct atom_value *v = &ref->value[i];
1164                int deref = 0;
1165                const char *refname;
1166                const char *formatp;
1167                struct branch *branch = NULL;
1168
1169                v->handler = append_atom;
1170                v->atom = atom;
1171
1172                if (*name == '*') {
1173                        deref = 1;
1174                        name++;
1175                }
1176
1177                if (starts_with(name, "refname")) {
1178                        refname = ref->refname;
1179                        if (ref->kind & FILTER_REFS_DETACHED_HEAD)
1180                                refname = get_head_description();
1181                } else if (starts_with(name, "symref"))
1182                        refname = ref->symref ? ref->symref : "";
1183                else if (starts_with(name, "upstream")) {
1184                        const char *branch_name;
1185                        /* only local branches may have an upstream */
1186                        if (!skip_prefix(ref->refname, "refs/heads/",
1187                                         &branch_name))
1188                                continue;
1189                        branch = branch_get(branch_name);
1190
1191                        refname = branch_get_upstream(branch, NULL);
1192                        if (refname)
1193                                fill_remote_ref_details(atom, refname, branch, &v->s);
1194                        continue;
1195                } else if (starts_with(name, "push")) {
1196                        const char *branch_name;
1197                        if (!skip_prefix(ref->refname, "refs/heads/",
1198                                         &branch_name))
1199                                continue;
1200                        branch = branch_get(branch_name);
1201
1202                        refname = branch_get_push(branch, NULL);
1203                        if (!refname)
1204                                continue;
1205                        fill_remote_ref_details(atom, refname, branch, &v->s);
1206                        continue;
1207                } else if (starts_with(name, "color:")) {
1208                        v->s = atom->u.color;
1209                        continue;
1210                } else if (!strcmp(name, "flag")) {
1211                        char buf[256], *cp = buf;
1212                        if (ref->flag & REF_ISSYMREF)
1213                                cp = copy_advance(cp, ",symref");
1214                        if (ref->flag & REF_ISPACKED)
1215                                cp = copy_advance(cp, ",packed");
1216                        if (cp == buf)
1217                                v->s = "";
1218                        else {
1219                                *cp = '\0';
1220                                v->s = xstrdup(buf + 1);
1221                        }
1222                        continue;
1223                } else if (!deref && grab_objectname(name, ref->objectname, v, atom)) {
1224                        continue;
1225                } else if (!strcmp(name, "HEAD")) {
1226                        const char *head;
1227                        unsigned char sha1[20];
1228
1229                        head = resolve_ref_unsafe("HEAD", RESOLVE_REF_READING,
1230                                                  sha1, NULL);
1231                        if (head && !strcmp(ref->refname, head))
1232                                v->s = "*";
1233                        else
1234                                v->s = " ";
1235                        continue;
1236                } else if (starts_with(name, "align")) {
1237                        v->handler = align_atom_handler;
1238                        continue;
1239                } else if (!strcmp(name, "end")) {
1240                        v->handler = end_atom_handler;
1241                        continue;
1242                } else if (starts_with(name, "if")) {
1243                        const char *s;
1244
1245                        if (skip_prefix(name, "if:", &s))
1246                                v->s = xstrdup(s);
1247                        v->handler = if_atom_handler;
1248                        continue;
1249                } else if (!strcmp(name, "then")) {
1250                        v->handler = then_atom_handler;
1251                        continue;
1252                } else if (!strcmp(name, "else")) {
1253                        v->handler = else_atom_handler;
1254                        continue;
1255                } else
1256                        continue;
1257
1258                formatp = strchr(name, ':');
1259                if (formatp) {
1260                        const char *arg;
1261
1262                        formatp++;
1263                        if (!strcmp(formatp, "short"))
1264                                refname = shorten_unambiguous_ref(refname,
1265                                                      warn_ambiguous_refs);
1266                        else if (skip_prefix(formatp, "strip=", &arg))
1267                                refname = strip_ref_components(refname, arg);
1268                        else
1269                                die(_("unknown %.*s format %s"),
1270                                    (int)(formatp - name), name, formatp);
1271                }
1272
1273                if (!deref)
1274                        v->s = refname;
1275                else
1276                        v->s = xstrfmt("%s^{}", refname);
1277        }
1278
1279        for (i = 0; i < used_atom_cnt; i++) {
1280                struct atom_value *v = &ref->value[i];
1281                if (v->s == NULL)
1282                        goto need_obj;
1283        }
1284        return;
1285
1286 need_obj:
1287        buf = get_obj(ref->objectname, &obj, &size, &eaten);
1288        if (!buf)
1289                die(_("missing object %s for %s"),
1290                    sha1_to_hex(ref->objectname), ref->refname);
1291        if (!obj)
1292                die(_("parse_object_buffer failed on %s for %s"),
1293                    sha1_to_hex(ref->objectname), ref->refname);
1294
1295        grab_values(ref->value, 0, obj, buf, size);
1296        if (!eaten)
1297                free(buf);
1298
1299        /*
1300         * If there is no atom that wants to know about tagged
1301         * object, we are done.
1302         */
1303        if (!need_tagged || (obj->type != OBJ_TAG))
1304                return;
1305
1306        /*
1307         * If it is a tag object, see if we use a value that derefs
1308         * the object, and if we do grab the object it refers to.
1309         */
1310        tagged = ((struct tag *)obj)->tagged->oid.hash;
1311
1312        /*
1313         * NEEDSWORK: This derefs tag only once, which
1314         * is good to deal with chains of trust, but
1315         * is not consistent with what deref_tag() does
1316         * which peels the onion to the core.
1317         */
1318        buf = get_obj(tagged, &obj, &size, &eaten);
1319        if (!buf)
1320                die(_("missing object %s for %s"),
1321                    sha1_to_hex(tagged), ref->refname);
1322        if (!obj)
1323                die(_("parse_object_buffer failed on %s for %s"),
1324                    sha1_to_hex(tagged), ref->refname);
1325        grab_values(ref->value, 1, obj, buf, size);
1326        if (!eaten)
1327                free(buf);
1328}
1329
1330/*
1331 * Given a ref, return the value for the atom.  This lazily gets value
1332 * out of the object by calling populate value.
1333 */
1334static void get_ref_atom_value(struct ref_array_item *ref, int atom, struct atom_value **v)
1335{
1336        if (!ref->value) {
1337                populate_value(ref);
1338                fill_missing_values(ref->value);
1339        }
1340        *v = &ref->value[atom];
1341}
1342
1343enum contains_result {
1344        CONTAINS_UNKNOWN = -1,
1345        CONTAINS_NO = 0,
1346        CONTAINS_YES = 1
1347};
1348
1349/*
1350 * Mimicking the real stack, this stack lives on the heap, avoiding stack
1351 * overflows.
1352 *
1353 * At each recursion step, the stack items points to the commits whose
1354 * ancestors are to be inspected.
1355 */
1356struct contains_stack {
1357        int nr, alloc;
1358        struct contains_stack_entry {
1359                struct commit *commit;
1360                struct commit_list *parents;
1361        } *contains_stack;
1362};
1363
1364static int in_commit_list(const struct commit_list *want, struct commit *c)
1365{
1366        for (; want; want = want->next)
1367                if (!oidcmp(&want->item->object.oid, &c->object.oid))
1368                        return 1;
1369        return 0;
1370}
1371
1372/*
1373 * Test whether the candidate or one of its parents is contained in the list.
1374 * Do not recurse to find out, though, but return -1 if inconclusive.
1375 */
1376static enum contains_result contains_test(struct commit *candidate,
1377                            const struct commit_list *want)
1378{
1379        /* was it previously marked as containing a want commit? */
1380        if (candidate->object.flags & TMP_MARK)
1381                return 1;
1382        /* or marked as not possibly containing a want commit? */
1383        if (candidate->object.flags & UNINTERESTING)
1384                return 0;
1385        /* or are we it? */
1386        if (in_commit_list(want, candidate)) {
1387                candidate->object.flags |= TMP_MARK;
1388                return 1;
1389        }
1390
1391        if (parse_commit(candidate) < 0)
1392                return 0;
1393
1394        return -1;
1395}
1396
1397static void push_to_contains_stack(struct commit *candidate, struct contains_stack *contains_stack)
1398{
1399        ALLOC_GROW(contains_stack->contains_stack, contains_stack->nr + 1, contains_stack->alloc);
1400        contains_stack->contains_stack[contains_stack->nr].commit = candidate;
1401        contains_stack->contains_stack[contains_stack->nr++].parents = candidate->parents;
1402}
1403
1404static enum contains_result contains_tag_algo(struct commit *candidate,
1405                const struct commit_list *want)
1406{
1407        struct contains_stack contains_stack = { 0, 0, NULL };
1408        int result = contains_test(candidate, want);
1409
1410        if (result != CONTAINS_UNKNOWN)
1411                return result;
1412
1413        push_to_contains_stack(candidate, &contains_stack);
1414        while (contains_stack.nr) {
1415                struct contains_stack_entry *entry = &contains_stack.contains_stack[contains_stack.nr - 1];
1416                struct commit *commit = entry->commit;
1417                struct commit_list *parents = entry->parents;
1418
1419                if (!parents) {
1420                        commit->object.flags |= UNINTERESTING;
1421                        contains_stack.nr--;
1422                }
1423                /*
1424                 * If we just popped the stack, parents->item has been marked,
1425                 * therefore contains_test will return a meaningful 0 or 1.
1426                 */
1427                else switch (contains_test(parents->item, want)) {
1428                case CONTAINS_YES:
1429                        commit->object.flags |= TMP_MARK;
1430                        contains_stack.nr--;
1431                        break;
1432                case CONTAINS_NO:
1433                        entry->parents = parents->next;
1434                        break;
1435                case CONTAINS_UNKNOWN:
1436                        push_to_contains_stack(parents->item, &contains_stack);
1437                        break;
1438                }
1439        }
1440        free(contains_stack.contains_stack);
1441        return contains_test(candidate, want);
1442}
1443
1444static int commit_contains(struct ref_filter *filter, struct commit *commit)
1445{
1446        if (filter->with_commit_tag_algo)
1447                return contains_tag_algo(commit, filter->with_commit);
1448        return is_descendant_of(commit, filter->with_commit);
1449}
1450
1451/*
1452 * Return 1 if the refname matches one of the patterns, otherwise 0.
1453 * A pattern can be a literal prefix (e.g. a refname "refs/heads/master"
1454 * matches a pattern "refs/heads/mas") or a wildcard (e.g. the same ref
1455 * matches "refs/heads/mas*", too).
1456 */
1457static int match_pattern(const struct ref_filter *filter, const char *refname)
1458{
1459        const char **patterns = filter->name_patterns;
1460        unsigned flags = 0;
1461
1462        if (filter->ignore_case)
1463                flags |= WM_CASEFOLD;
1464
1465        /*
1466         * When no '--format' option is given we need to skip the prefix
1467         * for matching refs of tags and branches.
1468         */
1469        (void)(skip_prefix(refname, "refs/tags/", &refname) ||
1470               skip_prefix(refname, "refs/heads/", &refname) ||
1471               skip_prefix(refname, "refs/remotes/", &refname) ||
1472               skip_prefix(refname, "refs/", &refname));
1473
1474        for (; *patterns; patterns++) {
1475                if (!wildmatch(*patterns, refname, flags, NULL))
1476                        return 1;
1477        }
1478        return 0;
1479}
1480
1481/*
1482 * Return 1 if the refname matches one of the patterns, otherwise 0.
1483 * A pattern can be path prefix (e.g. a refname "refs/heads/master"
1484 * matches a pattern "refs/heads/" but not "refs/heads/m") or a
1485 * wildcard (e.g. the same ref matches "refs/heads/m*", too).
1486 */
1487static int match_name_as_path(const struct ref_filter *filter, const char *refname)
1488{
1489        const char **pattern = filter->name_patterns;
1490        int namelen = strlen(refname);
1491        unsigned flags = WM_PATHNAME;
1492
1493        if (filter->ignore_case)
1494                flags |= WM_CASEFOLD;
1495
1496        for (; *pattern; pattern++) {
1497                const char *p = *pattern;
1498                int plen = strlen(p);
1499
1500                if ((plen <= namelen) &&
1501                    !strncmp(refname, p, plen) &&
1502                    (refname[plen] == '\0' ||
1503                     refname[plen] == '/' ||
1504                     p[plen-1] == '/'))
1505                        return 1;
1506                if (!wildmatch(p, refname, WM_PATHNAME, NULL))
1507                        return 1;
1508        }
1509        return 0;
1510}
1511
1512/* Return 1 if the refname matches one of the patterns, otherwise 0. */
1513static int filter_pattern_match(struct ref_filter *filter, const char *refname)
1514{
1515        if (!*filter->name_patterns)
1516                return 1; /* No pattern always matches */
1517        if (filter->match_as_path)
1518                return match_name_as_path(filter, refname);
1519        return match_pattern(filter, refname);
1520}
1521
1522/*
1523 * Given a ref (sha1, refname), check if the ref belongs to the array
1524 * of sha1s. If the given ref is a tag, check if the given tag points
1525 * at one of the sha1s in the given sha1 array.
1526 * the given sha1_array.
1527 * NEEDSWORK:
1528 * 1. Only a single level of inderection is obtained, we might want to
1529 * change this to account for multiple levels (e.g. annotated tags
1530 * pointing to annotated tags pointing to a commit.)
1531 * 2. As the refs are cached we might know what refname peels to without
1532 * the need to parse the object via parse_object(). peel_ref() might be a
1533 * more efficient alternative to obtain the pointee.
1534 */
1535static const unsigned char *match_points_at(struct sha1_array *points_at,
1536                                            const unsigned char *sha1,
1537                                            const char *refname)
1538{
1539        const unsigned char *tagged_sha1 = NULL;
1540        struct object *obj;
1541
1542        if (sha1_array_lookup(points_at, sha1) >= 0)
1543                return sha1;
1544        obj = parse_object(sha1);
1545        if (!obj)
1546                die(_("malformed object at '%s'"), refname);
1547        if (obj->type == OBJ_TAG)
1548                tagged_sha1 = ((struct tag *)obj)->tagged->oid.hash;
1549        if (tagged_sha1 && sha1_array_lookup(points_at, tagged_sha1) >= 0)
1550                return tagged_sha1;
1551        return NULL;
1552}
1553
1554/* Allocate space for a new ref_array_item and copy the objectname and flag to it */
1555static struct ref_array_item *new_ref_array_item(const char *refname,
1556                                                 const unsigned char *objectname,
1557                                                 int flag)
1558{
1559        struct ref_array_item *ref;
1560        FLEX_ALLOC_STR(ref, refname, refname);
1561        hashcpy(ref->objectname, objectname);
1562        ref->flag = flag;
1563
1564        return ref;
1565}
1566
1567static int filter_ref_kind(struct ref_filter *filter, const char *refname)
1568{
1569        unsigned int i;
1570
1571        static struct {
1572                const char *prefix;
1573                unsigned int kind;
1574        } ref_kind[] = {
1575                { "refs/heads/" , FILTER_REFS_BRANCHES },
1576                { "refs/remotes/" , FILTER_REFS_REMOTES },
1577                { "refs/tags/", FILTER_REFS_TAGS}
1578        };
1579
1580        if (filter->kind == FILTER_REFS_BRANCHES ||
1581            filter->kind == FILTER_REFS_REMOTES ||
1582            filter->kind == FILTER_REFS_TAGS)
1583                return filter->kind;
1584        else if (!strcmp(refname, "HEAD"))
1585                return FILTER_REFS_DETACHED_HEAD;
1586
1587        for (i = 0; i < ARRAY_SIZE(ref_kind); i++) {
1588                if (starts_with(refname, ref_kind[i].prefix))
1589                        return ref_kind[i].kind;
1590        }
1591
1592        return FILTER_REFS_OTHERS;
1593}
1594
1595/*
1596 * A call-back given to for_each_ref().  Filter refs and keep them for
1597 * later object processing.
1598 */
1599static int ref_filter_handler(const char *refname, const struct object_id *oid, int flag, void *cb_data)
1600{
1601        struct ref_filter_cbdata *ref_cbdata = cb_data;
1602        struct ref_filter *filter = ref_cbdata->filter;
1603        struct ref_array_item *ref;
1604        struct commit *commit = NULL;
1605        unsigned int kind;
1606
1607        if (flag & REF_BAD_NAME) {
1608                warning(_("ignoring ref with broken name %s"), refname);
1609                return 0;
1610        }
1611
1612        if (flag & REF_ISBROKEN) {
1613                warning(_("ignoring broken ref %s"), refname);
1614                return 0;
1615        }
1616
1617        /* Obtain the current ref kind from filter_ref_kind() and ignore unwanted refs. */
1618        kind = filter_ref_kind(filter, refname);
1619        if (!(kind & filter->kind))
1620                return 0;
1621
1622        if (!filter_pattern_match(filter, refname))
1623                return 0;
1624
1625        if (filter->points_at.nr && !match_points_at(&filter->points_at, oid->hash, refname))
1626                return 0;
1627
1628        /*
1629         * A merge filter is applied on refs pointing to commits. Hence
1630         * obtain the commit using the 'oid' available and discard all
1631         * non-commits early. The actual filtering is done later.
1632         */
1633        if (filter->merge_commit || filter->with_commit || filter->verbose) {
1634                commit = lookup_commit_reference_gently(oid->hash, 1);
1635                if (!commit)
1636                        return 0;
1637                /* We perform the filtering for the '--contains' option */
1638                if (filter->with_commit &&
1639                    !commit_contains(filter, commit))
1640                        return 0;
1641        }
1642
1643        /*
1644         * We do not open the object yet; sort may only need refname
1645         * to do its job and the resulting list may yet to be pruned
1646         * by maxcount logic.
1647         */
1648        ref = new_ref_array_item(refname, oid->hash, flag);
1649        ref->commit = commit;
1650
1651        REALLOC_ARRAY(ref_cbdata->array->items, ref_cbdata->array->nr + 1);
1652        ref_cbdata->array->items[ref_cbdata->array->nr++] = ref;
1653        ref->kind = kind;
1654        return 0;
1655}
1656
1657/*  Free memory allocated for a ref_array_item */
1658static void free_array_item(struct ref_array_item *item)
1659{
1660        free((char *)item->symref);
1661        free(item);
1662}
1663
1664/* Free all memory allocated for ref_array */
1665void ref_array_clear(struct ref_array *array)
1666{
1667        int i;
1668
1669        for (i = 0; i < array->nr; i++)
1670                free_array_item(array->items[i]);
1671        free(array->items);
1672        array->items = NULL;
1673        array->nr = array->alloc = 0;
1674}
1675
1676static void do_merge_filter(struct ref_filter_cbdata *ref_cbdata)
1677{
1678        struct rev_info revs;
1679        int i, old_nr;
1680        struct ref_filter *filter = ref_cbdata->filter;
1681        struct ref_array *array = ref_cbdata->array;
1682        struct commit **to_clear = xcalloc(sizeof(struct commit *), array->nr);
1683
1684        init_revisions(&revs, NULL);
1685
1686        for (i = 0; i < array->nr; i++) {
1687                struct ref_array_item *item = array->items[i];
1688                add_pending_object(&revs, &item->commit->object, item->refname);
1689                to_clear[i] = item->commit;
1690        }
1691
1692        filter->merge_commit->object.flags |= UNINTERESTING;
1693        add_pending_object(&revs, &filter->merge_commit->object, "");
1694
1695        revs.limited = 1;
1696        if (prepare_revision_walk(&revs))
1697                die(_("revision walk setup failed"));
1698
1699        old_nr = array->nr;
1700        array->nr = 0;
1701
1702        for (i = 0; i < old_nr; i++) {
1703                struct ref_array_item *item = array->items[i];
1704                struct commit *commit = item->commit;
1705
1706                int is_merged = !!(commit->object.flags & UNINTERESTING);
1707
1708                if (is_merged == (filter->merge == REF_FILTER_MERGED_INCLUDE))
1709                        array->items[array->nr++] = array->items[i];
1710                else
1711                        free_array_item(item);
1712        }
1713
1714        for (i = 0; i < old_nr; i++)
1715                clear_commit_marks(to_clear[i], ALL_REV_FLAGS);
1716        clear_commit_marks(filter->merge_commit, ALL_REV_FLAGS);
1717        free(to_clear);
1718}
1719
1720/*
1721 * API for filtering a set of refs. Based on the type of refs the user
1722 * has requested, we iterate through those refs and apply filters
1723 * as per the given ref_filter structure and finally store the
1724 * filtered refs in the ref_array structure.
1725 */
1726int filter_refs(struct ref_array *array, struct ref_filter *filter, unsigned int type)
1727{
1728        struct ref_filter_cbdata ref_cbdata;
1729        int ret = 0;
1730        unsigned int broken = 0;
1731
1732        ref_cbdata.array = array;
1733        ref_cbdata.filter = filter;
1734
1735        if (type & FILTER_REFS_INCLUDE_BROKEN)
1736                broken = 1;
1737        filter->kind = type & FILTER_REFS_KIND_MASK;
1738
1739        /*  Simple per-ref filtering */
1740        if (!filter->kind)
1741                die("filter_refs: invalid type");
1742        else {
1743                /*
1744                 * For common cases where we need only branches or remotes or tags,
1745                 * we only iterate through those refs. If a mix of refs is needed,
1746                 * we iterate over all refs and filter out required refs with the help
1747                 * of filter_ref_kind().
1748                 */
1749                if (filter->kind == FILTER_REFS_BRANCHES)
1750                        ret = for_each_fullref_in("refs/heads/", ref_filter_handler, &ref_cbdata, broken);
1751                else if (filter->kind == FILTER_REFS_REMOTES)
1752                        ret = for_each_fullref_in("refs/remotes/", ref_filter_handler, &ref_cbdata, broken);
1753                else if (filter->kind == FILTER_REFS_TAGS)
1754                        ret = for_each_fullref_in("refs/tags/", ref_filter_handler, &ref_cbdata, broken);
1755                else if (filter->kind & FILTER_REFS_ALL)
1756                        ret = for_each_fullref_in("", ref_filter_handler, &ref_cbdata, broken);
1757                if (!ret && (filter->kind & FILTER_REFS_DETACHED_HEAD))
1758                        head_ref(ref_filter_handler, &ref_cbdata);
1759        }
1760
1761
1762        /*  Filters that need revision walking */
1763        if (filter->merge_commit)
1764                do_merge_filter(&ref_cbdata);
1765
1766        return ret;
1767}
1768
1769static int cmp_ref_sorting(struct ref_sorting *s, struct ref_array_item *a, struct ref_array_item *b)
1770{
1771        struct atom_value *va, *vb;
1772        int cmp;
1773        cmp_type cmp_type = used_atom[s->atom].type;
1774        int (*cmp_fn)(const char *, const char *);
1775
1776        get_ref_atom_value(a, s->atom, &va);
1777        get_ref_atom_value(b, s->atom, &vb);
1778        cmp_fn = s->ignore_case ? strcasecmp : strcmp;
1779        if (s->version)
1780                cmp = versioncmp(va->s, vb->s);
1781        else if (cmp_type == FIELD_STR)
1782                cmp = cmp_fn(va->s, vb->s);
1783        else {
1784                if (va->ul < vb->ul)
1785                        cmp = -1;
1786                else if (va->ul == vb->ul)
1787                        cmp = cmp_fn(a->refname, b->refname);
1788                else
1789                        cmp = 1;
1790        }
1791
1792        return (s->reverse) ? -cmp : cmp;
1793}
1794
1795static struct ref_sorting *ref_sorting;
1796static int compare_refs(const void *a_, const void *b_)
1797{
1798        struct ref_array_item *a = *((struct ref_array_item **)a_);
1799        struct ref_array_item *b = *((struct ref_array_item **)b_);
1800        struct ref_sorting *s;
1801
1802        for (s = ref_sorting; s; s = s->next) {
1803                int cmp = cmp_ref_sorting(s, a, b);
1804                if (cmp)
1805                        return cmp;
1806        }
1807        return 0;
1808}
1809
1810void ref_array_sort(struct ref_sorting *sorting, struct ref_array *array)
1811{
1812        ref_sorting = sorting;
1813        QSORT(array->items, array->nr, compare_refs);
1814}
1815
1816static void append_literal(const char *cp, const char *ep, struct ref_formatting_state *state)
1817{
1818        struct strbuf *s = &state->stack->output;
1819
1820        while (*cp && (!ep || cp < ep)) {
1821                if (*cp == '%') {
1822                        if (cp[1] == '%')
1823                                cp++;
1824                        else {
1825                                int ch = hex2chr(cp + 1);
1826                                if (0 <= ch) {
1827                                        strbuf_addch(s, ch);
1828                                        cp += 3;
1829                                        continue;
1830                                }
1831                        }
1832                }
1833                strbuf_addch(s, *cp);
1834                cp++;
1835        }
1836}
1837
1838void format_ref_array_item(struct ref_array_item *info, const char *format,
1839                           int quote_style, struct strbuf *final_buf)
1840{
1841        const char *cp, *sp, *ep;
1842        struct ref_formatting_state state = REF_FORMATTING_STATE_INIT;
1843
1844        state.quote_style = quote_style;
1845        push_stack_element(&state.stack);
1846
1847        for (cp = format; *cp && (sp = find_next(cp)); cp = ep + 1) {
1848                struct atom_value *atomv;
1849
1850                ep = strchr(sp, ')');
1851                if (cp < sp)
1852                        append_literal(cp, sp, &state);
1853                get_ref_atom_value(info, parse_ref_filter_atom(sp + 2, ep), &atomv);
1854                atomv->handler(atomv, &state);
1855        }
1856        if (*cp) {
1857                sp = cp + strlen(cp);
1858                append_literal(cp, sp, &state);
1859        }
1860        if (need_color_reset_at_eol) {
1861                struct atom_value resetv;
1862                char color[COLOR_MAXLEN] = "";
1863
1864                if (color_parse("reset", color) < 0)
1865                        die("BUG: couldn't parse 'reset' as a color");
1866                resetv.s = color;
1867                append_atom(&resetv, &state);
1868        }
1869        if (state.stack->prev)
1870                die(_("format: %%(end) atom missing"));
1871        strbuf_addbuf(final_buf, &state.stack->output);
1872        pop_stack_element(&state.stack);
1873}
1874
1875void show_ref_array_item(struct ref_array_item *info, const char *format, int quote_style)
1876{
1877        struct strbuf final_buf = STRBUF_INIT;
1878
1879        format_ref_array_item(info, format, quote_style, &final_buf);
1880        fwrite(final_buf.buf, 1, final_buf.len, stdout);
1881        strbuf_release(&final_buf);
1882        putchar('\n');
1883}
1884
1885/*  If no sorting option is given, use refname to sort as default */
1886struct ref_sorting *ref_default_sorting(void)
1887{
1888        static const char cstr_name[] = "refname";
1889
1890        struct ref_sorting *sorting = xcalloc(1, sizeof(*sorting));
1891
1892        sorting->next = NULL;
1893        sorting->atom = parse_ref_filter_atom(cstr_name, cstr_name + strlen(cstr_name));
1894        return sorting;
1895}
1896
1897int parse_opt_ref_sorting(const struct option *opt, const char *arg, int unset)
1898{
1899        struct ref_sorting **sorting_tail = opt->value;
1900        struct ref_sorting *s;
1901        int len;
1902
1903        if (!arg) /* should --no-sort void the list ? */
1904                return -1;
1905
1906        s = xcalloc(1, sizeof(*s));
1907        s->next = *sorting_tail;
1908        *sorting_tail = s;
1909
1910        if (*arg == '-') {
1911                s->reverse = 1;
1912                arg++;
1913        }
1914        if (skip_prefix(arg, "version:", &arg) ||
1915            skip_prefix(arg, "v:", &arg))
1916                s->version = 1;
1917        len = strlen(arg);
1918        s->atom = parse_ref_filter_atom(arg, arg+len);
1919        return 0;
1920}
1921
1922int parse_opt_merge_filter(const struct option *opt, const char *arg, int unset)
1923{
1924        struct ref_filter *rf = opt->value;
1925        unsigned char sha1[20];
1926
1927        rf->merge = starts_with(opt->long_name, "no")
1928                ? REF_FILTER_MERGED_OMIT
1929                : REF_FILTER_MERGED_INCLUDE;
1930
1931        if (get_sha1(arg, sha1))
1932                die(_("malformed object name %s"), arg);
1933
1934        rf->merge_commit = lookup_commit_reference_gently(sha1, 0);
1935        if (!rf->merge_commit)
1936                return opterror(opt, "must point to a commit", 0);
1937
1938        return 0;
1939}