ref-filter.con commit ref-filter: Do not abruptly die when using the 'lstrip=<N>' option (3a42980)
   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
  35struct refname_atom {
  36        enum { R_NORMAL, R_SHORT, R_LSTRIP } option;
  37        unsigned int lstrip;
  38};
  39
  40/*
  41 * An atom is a valid field atom listed below, possibly prefixed with
  42 * a "*" to denote deref_tag().
  43 *
  44 * We parse given format string and sort specifiers, and make a list
  45 * of properties that we need to extract out of objects.  ref_array_item
  46 * structure will hold an array of values extracted that can be
  47 * indexed with the "atom number", which is an index into this
  48 * array.
  49 */
  50static struct used_atom {
  51        const char *name;
  52        cmp_type type;
  53        union {
  54                char color[COLOR_MAXLEN];
  55                struct align align;
  56                struct {
  57                        enum { RR_REF, RR_TRACK, RR_TRACKSHORT } option;
  58                        struct refname_atom refname;
  59                        unsigned int nobracket : 1;
  60                } remote_ref;
  61                struct {
  62                        enum { C_BARE, C_BODY, C_BODY_DEP, C_LINES, C_SIG, C_SUB, C_TRAILERS } option;
  63                        unsigned int nlines;
  64                } contents;
  65                struct {
  66                        cmp_status cmp_status;
  67                        const char *str;
  68                } if_then_else;
  69                struct {
  70                        enum { O_FULL, O_LENGTH, O_SHORT } option;
  71                        unsigned int length;
  72                } objectname;
  73                struct refname_atom refname;
  74        } u;
  75} *used_atom;
  76static int used_atom_cnt, need_tagged, need_symref;
  77static int need_color_reset_at_eol;
  78
  79static void color_atom_parser(struct used_atom *atom, const char *color_value)
  80{
  81        if (!color_value)
  82                die(_("expected format: %%(color:<color>)"));
  83        if (color_parse(color_value, atom->u.color) < 0)
  84                die(_("unrecognized color: %%(color:%s)"), color_value);
  85}
  86
  87static void refname_atom_parser_internal(struct refname_atom *atom,
  88                                         const char *arg, const char *name)
  89{
  90        if (!arg)
  91                atom->option = R_NORMAL;
  92        else if (!strcmp(arg, "short"))
  93                atom->option = R_SHORT;
  94        else if (skip_prefix(arg, "lstrip=", &arg)) {
  95                atom->option = R_LSTRIP;
  96                if (strtoul_ui(arg, 10, &atom->lstrip) || atom->lstrip <= 0)
  97                        die(_("positive value expected refname:lstrip=%s"), arg);
  98        } else
  99                die(_("unrecognized %%(%s) argument: %s"), name, arg);
 100}
 101
 102static void remote_ref_atom_parser(struct used_atom *atom, const char *arg)
 103{
 104        struct string_list params = STRING_LIST_INIT_DUP;
 105        int i;
 106
 107        if (!arg) {
 108                atom->u.remote_ref.option = RR_REF;
 109                refname_atom_parser_internal(&atom->u.remote_ref.refname,
 110                                             arg, atom->name);
 111                return;
 112        }
 113
 114        atom->u.remote_ref.nobracket = 0;
 115        string_list_split(&params, arg, ',', -1);
 116
 117        for (i = 0; i < params.nr; i++) {
 118                const char *s = params.items[i].string;
 119
 120                if (!strcmp(s, "track"))
 121                        atom->u.remote_ref.option = RR_TRACK;
 122                else if (!strcmp(s, "trackshort"))
 123                        atom->u.remote_ref.option = RR_TRACKSHORT;
 124                else if (!strcmp(s, "nobracket"))
 125                        atom->u.remote_ref.nobracket = 1;
 126                else {
 127                        atom->u.remote_ref.option = RR_REF;
 128                        refname_atom_parser_internal(&atom->u.remote_ref.refname,
 129                                                     arg, atom->name);
 130                }
 131        }
 132
 133        string_list_clear(&params, 0);
 134}
 135
 136static void body_atom_parser(struct used_atom *atom, const char *arg)
 137{
 138        if (arg)
 139                die(_("%%(body) does not take arguments"));
 140        atom->u.contents.option = C_BODY_DEP;
 141}
 142
 143static void subject_atom_parser(struct used_atom *atom, const char *arg)
 144{
 145        if (arg)
 146                die(_("%%(subject) does not take arguments"));
 147        atom->u.contents.option = C_SUB;
 148}
 149
 150static void trailers_atom_parser(struct used_atom *atom, const char *arg)
 151{
 152        if (arg)
 153                die(_("%%(trailers) does not take arguments"));
 154        atom->u.contents.option = C_TRAILERS;
 155}
 156
 157static void contents_atom_parser(struct used_atom *atom, const char *arg)
 158{
 159        if (!arg)
 160                atom->u.contents.option = C_BARE;
 161        else if (!strcmp(arg, "body"))
 162                atom->u.contents.option = C_BODY;
 163        else if (!strcmp(arg, "signature"))
 164                atom->u.contents.option = C_SIG;
 165        else if (!strcmp(arg, "subject"))
 166                atom->u.contents.option = C_SUB;
 167        else if (!strcmp(arg, "trailers"))
 168                atom->u.contents.option = C_TRAILERS;
 169        else if (skip_prefix(arg, "lines=", &arg)) {
 170                atom->u.contents.option = C_LINES;
 171                if (strtoul_ui(arg, 10, &atom->u.contents.nlines))
 172                        die(_("positive value expected contents:lines=%s"), arg);
 173        } else
 174                die(_("unrecognized %%(contents) argument: %s"), arg);
 175}
 176
 177static void objectname_atom_parser(struct used_atom *atom, const char *arg)
 178{
 179        if (!arg)
 180                atom->u.objectname.option = O_FULL;
 181        else if (!strcmp(arg, "short"))
 182                atom->u.objectname.option = O_SHORT;
 183        else if (skip_prefix(arg, "short=", &arg)) {
 184                atom->u.objectname.option = O_LENGTH;
 185                if (strtoul_ui(arg, 10, &atom->u.objectname.length) ||
 186                    atom->u.objectname.length == 0)
 187                        die(_("positive value expected objectname:short=%s"), arg);
 188                if (atom->u.objectname.length < MINIMUM_ABBREV)
 189                        atom->u.objectname.length = MINIMUM_ABBREV;
 190        } else
 191                die(_("unrecognized %%(objectname) argument: %s"), arg);
 192}
 193
 194static void refname_atom_parser(struct used_atom *atom, const char *arg)
 195{
 196        return refname_atom_parser_internal(&atom->u.refname, arg, atom->name);
 197}
 198
 199static align_type parse_align_position(const char *s)
 200{
 201        if (!strcmp(s, "right"))
 202                return ALIGN_RIGHT;
 203        else if (!strcmp(s, "middle"))
 204                return ALIGN_MIDDLE;
 205        else if (!strcmp(s, "left"))
 206                return ALIGN_LEFT;
 207        return -1;
 208}
 209
 210static void align_atom_parser(struct used_atom *atom, const char *arg)
 211{
 212        struct align *align = &atom->u.align;
 213        struct string_list params = STRING_LIST_INIT_DUP;
 214        int i;
 215        unsigned int width = ~0U;
 216
 217        if (!arg)
 218                die(_("expected format: %%(align:<width>,<position>)"));
 219
 220        align->position = ALIGN_LEFT;
 221
 222        string_list_split(&params, arg, ',', -1);
 223        for (i = 0; i < params.nr; i++) {
 224                const char *s = params.items[i].string;
 225                int position;
 226
 227                if (skip_prefix(s, "position=", &s)) {
 228                        position = parse_align_position(s);
 229                        if (position < 0)
 230                                die(_("unrecognized position:%s"), s);
 231                        align->position = position;
 232                } else if (skip_prefix(s, "width=", &s)) {
 233                        if (strtoul_ui(s, 10, &width))
 234                                die(_("unrecognized width:%s"), s);
 235                } else if (!strtoul_ui(s, 10, &width))
 236                        ;
 237                else if ((position = parse_align_position(s)) >= 0)
 238                        align->position = position;
 239                else
 240                        die(_("unrecognized %%(align) argument: %s"), s);
 241        }
 242
 243        if (width == ~0U)
 244                die(_("positive width expected with the %%(align) atom"));
 245        align->width = width;
 246        string_list_clear(&params, 0);
 247}
 248
 249static void if_atom_parser(struct used_atom *atom, const char *arg)
 250{
 251        if (!arg) {
 252                atom->u.if_then_else.cmp_status = COMPARE_NONE;
 253                return;
 254        } else if (skip_prefix(arg, "equals=", &atom->u.if_then_else.str)) {
 255                atom->u.if_then_else.cmp_status = COMPARE_EQUAL;
 256        } else if (skip_prefix(arg, "notequals=", &atom->u.if_then_else.str)) {
 257                atom->u.if_then_else.cmp_status = COMPARE_UNEQUAL;
 258        } else {
 259                die(_("unrecognized %%(if) argument: %s"), arg);
 260        }
 261}
 262
 263
 264static struct {
 265        const char *name;
 266        cmp_type cmp_type;
 267        void (*parser)(struct used_atom *atom, const char *arg);
 268} valid_atom[] = {
 269        { "refname" , FIELD_STR, refname_atom_parser },
 270        { "objecttype" },
 271        { "objectsize", FIELD_ULONG },
 272        { "objectname", FIELD_STR, objectname_atom_parser },
 273        { "tree" },
 274        { "parent" },
 275        { "numparent", FIELD_ULONG },
 276        { "object" },
 277        { "type" },
 278        { "tag" },
 279        { "author" },
 280        { "authorname" },
 281        { "authoremail" },
 282        { "authordate", FIELD_TIME },
 283        { "committer" },
 284        { "committername" },
 285        { "committeremail" },
 286        { "committerdate", FIELD_TIME },
 287        { "tagger" },
 288        { "taggername" },
 289        { "taggeremail" },
 290        { "taggerdate", FIELD_TIME },
 291        { "creator" },
 292        { "creatordate", FIELD_TIME },
 293        { "subject", FIELD_STR, subject_atom_parser },
 294        { "body", FIELD_STR, body_atom_parser },
 295        { "trailers", FIELD_STR, trailers_atom_parser },
 296        { "contents", FIELD_STR, contents_atom_parser },
 297        { "upstream", FIELD_STR, remote_ref_atom_parser },
 298        { "push", FIELD_STR, remote_ref_atom_parser },
 299        { "symref", FIELD_STR, refname_atom_parser },
 300        { "flag" },
 301        { "HEAD" },
 302        { "color", FIELD_STR, color_atom_parser },
 303        { "align", FIELD_STR, align_atom_parser },
 304        { "end" },
 305        { "if", FIELD_STR, if_atom_parser },
 306        { "then" },
 307        { "else" },
 308};
 309
 310#define REF_FORMATTING_STATE_INIT  { 0, NULL }
 311
 312struct ref_formatting_stack {
 313        struct ref_formatting_stack *prev;
 314        struct strbuf output;
 315        void (*at_end)(struct ref_formatting_stack **stack);
 316        void *at_end_data;
 317};
 318
 319struct ref_formatting_state {
 320        int quote_style;
 321        struct ref_formatting_stack *stack;
 322};
 323
 324struct atom_value {
 325        const char *s;
 326        void (*handler)(struct atom_value *atomv, struct ref_formatting_state *state);
 327        unsigned long ul; /* used for sorting when not FIELD_STR */
 328        struct used_atom *atom;
 329};
 330
 331/*
 332 * Used to parse format string and sort specifiers
 333 */
 334int parse_ref_filter_atom(const char *atom, const char *ep)
 335{
 336        const char *sp;
 337        const char *arg;
 338        int i, at, atom_len;
 339
 340        sp = atom;
 341        if (*sp == '*' && sp < ep)
 342                sp++; /* deref */
 343        if (ep <= sp)
 344                die(_("malformed field name: %.*s"), (int)(ep-atom), atom);
 345
 346        /* Do we have the atom already used elsewhere? */
 347        for (i = 0; i < used_atom_cnt; i++) {
 348                int len = strlen(used_atom[i].name);
 349                if (len == ep - atom && !memcmp(used_atom[i].name, atom, len))
 350                        return i;
 351        }
 352
 353        /*
 354         * If the atom name has a colon, strip it and everything after
 355         * it off - it specifies the format for this entry, and
 356         * shouldn't be used for checking against the valid_atom
 357         * table.
 358         */
 359        arg = memchr(sp, ':', ep - sp);
 360        atom_len = (arg ? arg : ep) - sp;
 361
 362        /* Is the atom a valid one? */
 363        for (i = 0; i < ARRAY_SIZE(valid_atom); i++) {
 364                int len = strlen(valid_atom[i].name);
 365                if (len == atom_len && !memcmp(valid_atom[i].name, sp, len))
 366                        break;
 367        }
 368
 369        if (ARRAY_SIZE(valid_atom) <= i)
 370                die(_("unknown field name: %.*s"), (int)(ep-atom), atom);
 371
 372        /* Add it in, including the deref prefix */
 373        at = used_atom_cnt;
 374        used_atom_cnt++;
 375        REALLOC_ARRAY(used_atom, used_atom_cnt);
 376        used_atom[at].name = xmemdupz(atom, ep - atom);
 377        used_atom[at].type = valid_atom[i].cmp_type;
 378        if (arg)
 379                arg = used_atom[at].name + (arg - atom) + 1;
 380        memset(&used_atom[at].u, 0, sizeof(used_atom[at].u));
 381        if (valid_atom[i].parser)
 382                valid_atom[i].parser(&used_atom[at], arg);
 383        if (*atom == '*')
 384                need_tagged = 1;
 385        if (!strcmp(valid_atom[i].name, "symref"))
 386                need_symref = 1;
 387        return at;
 388}
 389
 390static void quote_formatting(struct strbuf *s, const char *str, int quote_style)
 391{
 392        switch (quote_style) {
 393        case QUOTE_NONE:
 394                strbuf_addstr(s, str);
 395                break;
 396        case QUOTE_SHELL:
 397                sq_quote_buf(s, str);
 398                break;
 399        case QUOTE_PERL:
 400                perl_quote_buf(s, str);
 401                break;
 402        case QUOTE_PYTHON:
 403                python_quote_buf(s, str);
 404                break;
 405        case QUOTE_TCL:
 406                tcl_quote_buf(s, str);
 407                break;
 408        }
 409}
 410
 411static void append_atom(struct atom_value *v, struct ref_formatting_state *state)
 412{
 413        /*
 414         * Quote formatting is only done when the stack has a single
 415         * element. Otherwise quote formatting is done on the
 416         * element's entire output strbuf when the %(end) atom is
 417         * encountered.
 418         */
 419        if (!state->stack->prev)
 420                quote_formatting(&state->stack->output, v->s, state->quote_style);
 421        else
 422                strbuf_addstr(&state->stack->output, v->s);
 423}
 424
 425static void push_stack_element(struct ref_formatting_stack **stack)
 426{
 427        struct ref_formatting_stack *s = xcalloc(1, sizeof(struct ref_formatting_stack));
 428
 429        strbuf_init(&s->output, 0);
 430        s->prev = *stack;
 431        *stack = s;
 432}
 433
 434static void pop_stack_element(struct ref_formatting_stack **stack)
 435{
 436        struct ref_formatting_stack *current = *stack;
 437        struct ref_formatting_stack *prev = current->prev;
 438
 439        if (prev)
 440                strbuf_addbuf(&prev->output, &current->output);
 441        strbuf_release(&current->output);
 442        free(current);
 443        *stack = prev;
 444}
 445
 446static void end_align_handler(struct ref_formatting_stack **stack)
 447{
 448        struct ref_formatting_stack *cur = *stack;
 449        struct align *align = (struct align *)cur->at_end_data;
 450        struct strbuf s = STRBUF_INIT;
 451
 452        strbuf_utf8_align(&s, align->position, align->width, cur->output.buf);
 453        strbuf_swap(&cur->output, &s);
 454        strbuf_release(&s);
 455}
 456
 457static void align_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
 458{
 459        struct ref_formatting_stack *new;
 460
 461        push_stack_element(&state->stack);
 462        new = state->stack;
 463        new->at_end = end_align_handler;
 464        new->at_end_data = &atomv->atom->u.align;
 465}
 466
 467static void if_then_else_handler(struct ref_formatting_stack **stack)
 468{
 469        struct ref_formatting_stack *cur = *stack;
 470        struct ref_formatting_stack *prev = cur->prev;
 471        struct if_then_else *if_then_else = (struct if_then_else *)cur->at_end_data;
 472
 473        if (!if_then_else->then_atom_seen)
 474                die(_("format: %%(if) atom used without a %%(then) atom"));
 475
 476        if (if_then_else->else_atom_seen) {
 477                /*
 478                 * There is an %(else) atom: we need to drop one state from the
 479                 * stack, either the %(else) branch if the condition is satisfied, or
 480                 * the %(then) branch if it isn't.
 481                 */
 482                if (if_then_else->condition_satisfied) {
 483                        strbuf_reset(&cur->output);
 484                        pop_stack_element(&cur);
 485                } else {
 486                        strbuf_swap(&cur->output, &prev->output);
 487                        strbuf_reset(&cur->output);
 488                        pop_stack_element(&cur);
 489                }
 490        } else if (!if_then_else->condition_satisfied) {
 491                /*
 492                 * No %(else) atom: just drop the %(then) branch if the
 493                 * condition is not satisfied.
 494                 */
 495                strbuf_reset(&cur->output);
 496        }
 497
 498        *stack = cur;
 499        free(if_then_else);
 500}
 501
 502static void if_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
 503{
 504        struct ref_formatting_stack *new;
 505        struct if_then_else *if_then_else = xcalloc(sizeof(struct if_then_else), 1);
 506
 507        if_then_else->str = atomv->atom->u.if_then_else.str;
 508        if_then_else->cmp_status = atomv->atom->u.if_then_else.cmp_status;
 509
 510        push_stack_element(&state->stack);
 511        new = state->stack;
 512        new->at_end = if_then_else_handler;
 513        new->at_end_data = if_then_else;
 514}
 515
 516static int is_empty(const char *s)
 517{
 518        while (*s != '\0') {
 519                if (!isspace(*s))
 520                        return 0;
 521                s++;
 522        }
 523        return 1;
 524}
 525
 526static void then_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
 527{
 528        struct ref_formatting_stack *cur = state->stack;
 529        struct if_then_else *if_then_else = NULL;
 530
 531        if (cur->at_end == if_then_else_handler)
 532                if_then_else = (struct if_then_else *)cur->at_end_data;
 533        if (!if_then_else)
 534                die(_("format: %%(then) atom used without an %%(if) atom"));
 535        if (if_then_else->then_atom_seen)
 536                die(_("format: %%(then) atom used more than once"));
 537        if (if_then_else->else_atom_seen)
 538                die(_("format: %%(then) atom used after %%(else)"));
 539        if_then_else->then_atom_seen = 1;
 540        /*
 541         * If the 'equals' or 'notequals' attribute is used then
 542         * perform the required comparison. If not, only non-empty
 543         * strings satisfy the 'if' condition.
 544         */
 545        if (if_then_else->cmp_status == COMPARE_EQUAL) {
 546                if (!strcmp(if_then_else->str, cur->output.buf))
 547                        if_then_else->condition_satisfied = 1;
 548        } else if (if_then_else->cmp_status == COMPARE_UNEQUAL) {
 549                if (strcmp(if_then_else->str, cur->output.buf))
 550                        if_then_else->condition_satisfied = 1;
 551        } else if (cur->output.len && !is_empty(cur->output.buf))
 552                if_then_else->condition_satisfied = 1;
 553        strbuf_reset(&cur->output);
 554}
 555
 556static void else_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
 557{
 558        struct ref_formatting_stack *prev = state->stack;
 559        struct if_then_else *if_then_else = NULL;
 560
 561        if (prev->at_end == if_then_else_handler)
 562                if_then_else = (struct if_then_else *)prev->at_end_data;
 563        if (!if_then_else)
 564                die(_("format: %%(else) atom used without an %%(if) atom"));
 565        if (!if_then_else->then_atom_seen)
 566                die(_("format: %%(else) atom used without a %%(then) atom"));
 567        if (if_then_else->else_atom_seen)
 568                die(_("format: %%(else) atom used more than once"));
 569        if_then_else->else_atom_seen = 1;
 570        push_stack_element(&state->stack);
 571        state->stack->at_end_data = prev->at_end_data;
 572        state->stack->at_end = prev->at_end;
 573}
 574
 575static void end_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
 576{
 577        struct ref_formatting_stack *current = state->stack;
 578        struct strbuf s = STRBUF_INIT;
 579
 580        if (!current->at_end)
 581                die(_("format: %%(end) atom used without corresponding atom"));
 582        current->at_end(&state->stack);
 583
 584        /*  Stack may have been popped within at_end(), hence reset the current pointer */
 585        current = state->stack;
 586
 587        /*
 588         * Perform quote formatting when the stack element is that of
 589         * a supporting atom. If nested then perform quote formatting
 590         * only on the topmost supporting atom.
 591         */
 592        if (!current->prev->prev) {
 593                quote_formatting(&s, current->output.buf, state->quote_style);
 594                strbuf_swap(&current->output, &s);
 595        }
 596        strbuf_release(&s);
 597        pop_stack_element(&state->stack);
 598}
 599
 600/*
 601 * In a format string, find the next occurrence of %(atom).
 602 */
 603static const char *find_next(const char *cp)
 604{
 605        while (*cp) {
 606                if (*cp == '%') {
 607                        /*
 608                         * %( is the start of an atom;
 609                         * %% is a quoted per-cent.
 610                         */
 611                        if (cp[1] == '(')
 612                                return cp;
 613                        else if (cp[1] == '%')
 614                                cp++; /* skip over two % */
 615                        /* otherwise this is a singleton, literal % */
 616                }
 617                cp++;
 618        }
 619        return NULL;
 620}
 621
 622/*
 623 * Make sure the format string is well formed, and parse out
 624 * the used atoms.
 625 */
 626int verify_ref_format(const char *format)
 627{
 628        const char *cp, *sp;
 629
 630        need_color_reset_at_eol = 0;
 631        for (cp = format; *cp && (sp = find_next(cp)); ) {
 632                const char *color, *ep = strchr(sp, ')');
 633                int at;
 634
 635                if (!ep)
 636                        return error(_("malformed format string %s"), sp);
 637                /* sp points at "%(" and ep points at the closing ")" */
 638                at = parse_ref_filter_atom(sp + 2, ep);
 639                cp = ep + 1;
 640
 641                if (skip_prefix(used_atom[at].name, "color:", &color))
 642                        need_color_reset_at_eol = !!strcmp(color, "reset");
 643        }
 644        return 0;
 645}
 646
 647/*
 648 * Given an object name, read the object data and size, and return a
 649 * "struct object".  If the object data we are returning is also borrowed
 650 * by the "struct object" representation, set *eaten as well---it is a
 651 * signal from parse_object_buffer to us not to free the buffer.
 652 */
 653static void *get_obj(const unsigned char *sha1, struct object **obj, unsigned long *sz, int *eaten)
 654{
 655        enum object_type type;
 656        void *buf = read_sha1_file(sha1, &type, sz);
 657
 658        if (buf)
 659                *obj = parse_object_buffer(sha1, type, *sz, buf, eaten);
 660        else
 661                *obj = NULL;
 662        return buf;
 663}
 664
 665static int grab_objectname(const char *name, const unsigned char *sha1,
 666                           struct atom_value *v, struct used_atom *atom)
 667{
 668        if (starts_with(name, "objectname")) {
 669                if (atom->u.objectname.option == O_SHORT) {
 670                        v->s = xstrdup(find_unique_abbrev(sha1, DEFAULT_ABBREV));
 671                        return 1;
 672                } else if (atom->u.objectname.option == O_FULL) {
 673                        v->s = xstrdup(sha1_to_hex(sha1));
 674                        return 1;
 675                } else if (atom->u.objectname.option == O_LENGTH) {
 676                        v->s = xstrdup(find_unique_abbrev(sha1, atom->u.objectname.length));
 677                        return 1;
 678                } else
 679                        die("BUG: unknown %%(objectname) option");
 680        }
 681        return 0;
 682}
 683
 684/* See grab_values */
 685static void grab_common_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 686{
 687        int i;
 688
 689        for (i = 0; i < used_atom_cnt; i++) {
 690                const char *name = used_atom[i].name;
 691                struct atom_value *v = &val[i];
 692                if (!!deref != (*name == '*'))
 693                        continue;
 694                if (deref)
 695                        name++;
 696                if (!strcmp(name, "objecttype"))
 697                        v->s = typename(obj->type);
 698                else if (!strcmp(name, "objectsize")) {
 699                        v->ul = sz;
 700                        v->s = xstrfmt("%lu", sz);
 701                }
 702                else if (deref)
 703                        grab_objectname(name, obj->oid.hash, v, &used_atom[i]);
 704        }
 705}
 706
 707/* See grab_values */
 708static void grab_tag_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 709{
 710        int i;
 711        struct tag *tag = (struct tag *) obj;
 712
 713        for (i = 0; i < used_atom_cnt; i++) {
 714                const char *name = used_atom[i].name;
 715                struct atom_value *v = &val[i];
 716                if (!!deref != (*name == '*'))
 717                        continue;
 718                if (deref)
 719                        name++;
 720                if (!strcmp(name, "tag"))
 721                        v->s = tag->tag;
 722                else if (!strcmp(name, "type") && tag->tagged)
 723                        v->s = typename(tag->tagged->type);
 724                else if (!strcmp(name, "object") && tag->tagged)
 725                        v->s = xstrdup(oid_to_hex(&tag->tagged->oid));
 726        }
 727}
 728
 729/* See grab_values */
 730static void grab_commit_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 731{
 732        int i;
 733        struct commit *commit = (struct commit *) obj;
 734
 735        for (i = 0; i < used_atom_cnt; i++) {
 736                const char *name = used_atom[i].name;
 737                struct atom_value *v = &val[i];
 738                if (!!deref != (*name == '*'))
 739                        continue;
 740                if (deref)
 741                        name++;
 742                if (!strcmp(name, "tree")) {
 743                        v->s = xstrdup(oid_to_hex(&commit->tree->object.oid));
 744                }
 745                else if (!strcmp(name, "numparent")) {
 746                        v->ul = commit_list_count(commit->parents);
 747                        v->s = xstrfmt("%lu", v->ul);
 748                }
 749                else if (!strcmp(name, "parent")) {
 750                        struct commit_list *parents;
 751                        struct strbuf s = STRBUF_INIT;
 752                        for (parents = commit->parents; parents; parents = parents->next) {
 753                                struct commit *parent = parents->item;
 754                                if (parents != commit->parents)
 755                                        strbuf_addch(&s, ' ');
 756                                strbuf_addstr(&s, oid_to_hex(&parent->object.oid));
 757                        }
 758                        v->s = strbuf_detach(&s, NULL);
 759                }
 760        }
 761}
 762
 763static const char *find_wholine(const char *who, int wholen, const char *buf, unsigned long sz)
 764{
 765        const char *eol;
 766        while (*buf) {
 767                if (!strncmp(buf, who, wholen) &&
 768                    buf[wholen] == ' ')
 769                        return buf + wholen + 1;
 770                eol = strchr(buf, '\n');
 771                if (!eol)
 772                        return "";
 773                eol++;
 774                if (*eol == '\n')
 775                        return ""; /* end of header */
 776                buf = eol;
 777        }
 778        return "";
 779}
 780
 781static const char *copy_line(const char *buf)
 782{
 783        const char *eol = strchrnul(buf, '\n');
 784        return xmemdupz(buf, eol - buf);
 785}
 786
 787static const char *copy_name(const char *buf)
 788{
 789        const char *cp;
 790        for (cp = buf; *cp && *cp != '\n'; cp++) {
 791                if (!strncmp(cp, " <", 2))
 792                        return xmemdupz(buf, cp - buf);
 793        }
 794        return "";
 795}
 796
 797static const char *copy_email(const char *buf)
 798{
 799        const char *email = strchr(buf, '<');
 800        const char *eoemail;
 801        if (!email)
 802                return "";
 803        eoemail = strchr(email, '>');
 804        if (!eoemail)
 805                return "";
 806        return xmemdupz(email, eoemail + 1 - email);
 807}
 808
 809static char *copy_subject(const char *buf, unsigned long len)
 810{
 811        char *r = xmemdupz(buf, len);
 812        int i;
 813
 814        for (i = 0; i < len; i++)
 815                if (r[i] == '\n')
 816                        r[i] = ' ';
 817
 818        return r;
 819}
 820
 821static void grab_date(const char *buf, struct atom_value *v, const char *atomname)
 822{
 823        const char *eoemail = strstr(buf, "> ");
 824        char *zone;
 825        unsigned long timestamp;
 826        long tz;
 827        struct date_mode date_mode = { DATE_NORMAL };
 828        const char *formatp;
 829
 830        /*
 831         * We got here because atomname ends in "date" or "date<something>";
 832         * it's not possible that <something> is not ":<format>" because
 833         * parse_ref_filter_atom() wouldn't have allowed it, so we can assume that no
 834         * ":" means no format is specified, and use the default.
 835         */
 836        formatp = strchr(atomname, ':');
 837        if (formatp != NULL) {
 838                formatp++;
 839                parse_date_format(formatp, &date_mode);
 840        }
 841
 842        if (!eoemail)
 843                goto bad;
 844        timestamp = strtoul(eoemail + 2, &zone, 10);
 845        if (timestamp == ULONG_MAX)
 846                goto bad;
 847        tz = strtol(zone, NULL, 10);
 848        if ((tz == LONG_MIN || tz == LONG_MAX) && errno == ERANGE)
 849                goto bad;
 850        v->s = xstrdup(show_date(timestamp, tz, &date_mode));
 851        v->ul = timestamp;
 852        return;
 853 bad:
 854        v->s = "";
 855        v->ul = 0;
 856}
 857
 858/* See grab_values */
 859static void grab_person(const char *who, struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 860{
 861        int i;
 862        int wholen = strlen(who);
 863        const char *wholine = NULL;
 864
 865        for (i = 0; i < used_atom_cnt; i++) {
 866                const char *name = used_atom[i].name;
 867                struct atom_value *v = &val[i];
 868                if (!!deref != (*name == '*'))
 869                        continue;
 870                if (deref)
 871                        name++;
 872                if (strncmp(who, name, wholen))
 873                        continue;
 874                if (name[wholen] != 0 &&
 875                    strcmp(name + wholen, "name") &&
 876                    strcmp(name + wholen, "email") &&
 877                    !starts_with(name + wholen, "date"))
 878                        continue;
 879                if (!wholine)
 880                        wholine = find_wholine(who, wholen, buf, sz);
 881                if (!wholine)
 882                        return; /* no point looking for it */
 883                if (name[wholen] == 0)
 884                        v->s = copy_line(wholine);
 885                else if (!strcmp(name + wholen, "name"))
 886                        v->s = copy_name(wholine);
 887                else if (!strcmp(name + wholen, "email"))
 888                        v->s = copy_email(wholine);
 889                else if (starts_with(name + wholen, "date"))
 890                        grab_date(wholine, v, name);
 891        }
 892
 893        /*
 894         * For a tag or a commit object, if "creator" or "creatordate" is
 895         * requested, do something special.
 896         */
 897        if (strcmp(who, "tagger") && strcmp(who, "committer"))
 898                return; /* "author" for commit object is not wanted */
 899        if (!wholine)
 900                wholine = find_wholine(who, wholen, buf, sz);
 901        if (!wholine)
 902                return;
 903        for (i = 0; i < used_atom_cnt; i++) {
 904                const char *name = used_atom[i].name;
 905                struct atom_value *v = &val[i];
 906                if (!!deref != (*name == '*'))
 907                        continue;
 908                if (deref)
 909                        name++;
 910
 911                if (starts_with(name, "creatordate"))
 912                        grab_date(wholine, v, name);
 913                else if (!strcmp(name, "creator"))
 914                        v->s = copy_line(wholine);
 915        }
 916}
 917
 918static void find_subpos(const char *buf, unsigned long sz,
 919                        const char **sub, unsigned long *sublen,
 920                        const char **body, unsigned long *bodylen,
 921                        unsigned long *nonsiglen,
 922                        const char **sig, unsigned long *siglen)
 923{
 924        const char *eol;
 925        /* skip past header until we hit empty line */
 926        while (*buf && *buf != '\n') {
 927                eol = strchrnul(buf, '\n');
 928                if (*eol)
 929                        eol++;
 930                buf = eol;
 931        }
 932        /* skip any empty lines */
 933        while (*buf == '\n')
 934                buf++;
 935
 936        /* parse signature first; we might not even have a subject line */
 937        *sig = buf + parse_signature(buf, strlen(buf));
 938        *siglen = strlen(*sig);
 939
 940        /* subject is first non-empty line */
 941        *sub = buf;
 942        /* subject goes to first empty line */
 943        while (buf < *sig && *buf && *buf != '\n') {
 944                eol = strchrnul(buf, '\n');
 945                if (*eol)
 946                        eol++;
 947                buf = eol;
 948        }
 949        *sublen = buf - *sub;
 950        /* drop trailing newline, if present */
 951        if (*sublen && (*sub)[*sublen - 1] == '\n')
 952                *sublen -= 1;
 953
 954        /* skip any empty lines */
 955        while (*buf == '\n')
 956                buf++;
 957        *body = buf;
 958        *bodylen = strlen(buf);
 959        *nonsiglen = *sig - buf;
 960}
 961
 962/*
 963 * If 'lines' is greater than 0, append that many lines from the given
 964 * 'buf' of length 'size' to the given strbuf.
 965 */
 966static void append_lines(struct strbuf *out, const char *buf, unsigned long size, int lines)
 967{
 968        int i;
 969        const char *sp, *eol;
 970        size_t len;
 971
 972        sp = buf;
 973
 974        for (i = 0; i < lines && sp < buf + size; i++) {
 975                if (i)
 976                        strbuf_addstr(out, "\n    ");
 977                eol = memchr(sp, '\n', size - (sp - buf));
 978                len = eol ? eol - sp : size - (sp - buf);
 979                strbuf_add(out, sp, len);
 980                if (!eol)
 981                        break;
 982                sp = eol + 1;
 983        }
 984}
 985
 986/* See grab_values */
 987static void grab_sub_body_contents(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 988{
 989        int i;
 990        const char *subpos = NULL, *bodypos = NULL, *sigpos = NULL;
 991        unsigned long sublen = 0, bodylen = 0, nonsiglen = 0, siglen = 0;
 992
 993        for (i = 0; i < used_atom_cnt; i++) {
 994                struct used_atom *atom = &used_atom[i];
 995                const char *name = atom->name;
 996                struct atom_value *v = &val[i];
 997                if (!!deref != (*name == '*'))
 998                        continue;
 999                if (deref)
1000                        name++;
1001                if (strcmp(name, "subject") &&
1002                    strcmp(name, "body") &&
1003                    strcmp(name, "trailers") &&
1004                    !starts_with(name, "contents"))
1005                        continue;
1006                if (!subpos)
1007                        find_subpos(buf, sz,
1008                                    &subpos, &sublen,
1009                                    &bodypos, &bodylen, &nonsiglen,
1010                                    &sigpos, &siglen);
1011
1012                if (atom->u.contents.option == C_SUB)
1013                        v->s = copy_subject(subpos, sublen);
1014                else if (atom->u.contents.option == C_BODY_DEP)
1015                        v->s = xmemdupz(bodypos, bodylen);
1016                else if (atom->u.contents.option == C_BODY)
1017                        v->s = xmemdupz(bodypos, nonsiglen);
1018                else if (atom->u.contents.option == C_SIG)
1019                        v->s = xmemdupz(sigpos, siglen);
1020                else if (atom->u.contents.option == C_LINES) {
1021                        struct strbuf s = STRBUF_INIT;
1022                        const char *contents_end = bodylen + bodypos - siglen;
1023
1024                        /*  Size is the length of the message after removing the signature */
1025                        append_lines(&s, subpos, contents_end - subpos, atom->u.contents.nlines);
1026                        v->s = strbuf_detach(&s, NULL);
1027                } else if (atom->u.contents.option == C_TRAILERS) {
1028                        struct trailer_info info;
1029
1030                        /* Search for trailer info */
1031                        trailer_info_get(&info, subpos);
1032                        v->s = xmemdupz(info.trailer_start,
1033                                        info.trailer_end - info.trailer_start);
1034                        trailer_info_release(&info);
1035                } else if (atom->u.contents.option == C_BARE)
1036                        v->s = xstrdup(subpos);
1037        }
1038}
1039
1040/*
1041 * We want to have empty print-string for field requests
1042 * that do not apply (e.g. "authordate" for a tag object)
1043 */
1044static void fill_missing_values(struct atom_value *val)
1045{
1046        int i;
1047        for (i = 0; i < used_atom_cnt; i++) {
1048                struct atom_value *v = &val[i];
1049                if (v->s == NULL)
1050                        v->s = "";
1051        }
1052}
1053
1054/*
1055 * val is a list of atom_value to hold returned values.  Extract
1056 * the values for atoms in used_atom array out of (obj, buf, sz).
1057 * when deref is false, (obj, buf, sz) is the object that is
1058 * pointed at by the ref itself; otherwise it is the object the
1059 * ref (which is a tag) refers to.
1060 */
1061static void grab_values(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
1062{
1063        grab_common_values(val, deref, obj, buf, sz);
1064        switch (obj->type) {
1065        case OBJ_TAG:
1066                grab_tag_values(val, deref, obj, buf, sz);
1067                grab_sub_body_contents(val, deref, obj, buf, sz);
1068                grab_person("tagger", val, deref, obj, buf, sz);
1069                break;
1070        case OBJ_COMMIT:
1071                grab_commit_values(val, deref, obj, buf, sz);
1072                grab_sub_body_contents(val, deref, obj, buf, sz);
1073                grab_person("author", val, deref, obj, buf, sz);
1074                grab_person("committer", val, deref, obj, buf, sz);
1075                break;
1076        case OBJ_TREE:
1077                /* grab_tree_values(val, deref, obj, buf, sz); */
1078                break;
1079        case OBJ_BLOB:
1080                /* grab_blob_values(val, deref, obj, buf, sz); */
1081                break;
1082        default:
1083                die("Eh?  Object of type %d?", obj->type);
1084        }
1085}
1086
1087static inline char *copy_advance(char *dst, const char *src)
1088{
1089        while (*src)
1090                *dst++ = *src++;
1091        return dst;
1092}
1093
1094static const char *lstrip_ref_components(const char *refname, unsigned int len)
1095{
1096        long remaining = len;
1097        const char *start = refname;
1098
1099        while (remaining) {
1100                switch (*start++) {
1101                case '\0':
1102                        return "";
1103                case '/':
1104                        remaining--;
1105                        break;
1106                }
1107        }
1108        return start;
1109}
1110
1111static const char *show_ref(struct refname_atom *atom, const char *refname)
1112{
1113        if (atom->option == R_SHORT)
1114                return shorten_unambiguous_ref(refname, warn_ambiguous_refs);
1115        else if (atom->option == R_LSTRIP)
1116                return lstrip_ref_components(refname, atom->lstrip);
1117        else
1118                return refname;
1119}
1120
1121static void fill_remote_ref_details(struct used_atom *atom, const char *refname,
1122                                    struct branch *branch, const char **s)
1123{
1124        int num_ours, num_theirs;
1125        if (atom->u.remote_ref.option == RR_REF)
1126                *s = show_ref(&atom->u.remote_ref.refname, refname);
1127        else if (atom->u.remote_ref.option == RR_TRACK) {
1128                if (stat_tracking_info(branch, &num_ours,
1129                                       &num_theirs, NULL)) {
1130                        *s = xstrdup("gone");
1131                } else if (!num_ours && !num_theirs)
1132                        *s = "";
1133                else if (!num_ours)
1134                        *s = xstrfmt("behind %d", num_theirs);
1135                else if (!num_theirs)
1136                        *s = xstrfmt("ahead %d", num_ours);
1137                else
1138                        *s = xstrfmt("ahead %d, behind %d",
1139                                     num_ours, num_theirs);
1140                if (!atom->u.remote_ref.nobracket && *s[0]) {
1141                        const char *to_free = *s;
1142                        *s = xstrfmt("[%s]", *s);
1143                        free((void *)to_free);
1144                }
1145        } else if (atom->u.remote_ref.option == RR_TRACKSHORT) {
1146                if (stat_tracking_info(branch, &num_ours,
1147                                       &num_theirs, NULL))
1148                        return;
1149
1150                if (!num_ours && !num_theirs)
1151                        *s = "=";
1152                else if (!num_ours)
1153                        *s = "<";
1154                else if (!num_theirs)
1155                        *s = ">";
1156                else
1157                        *s = "<>";
1158        } else
1159                die("BUG: unhandled RR_* enum");
1160}
1161
1162char *get_head_description(void)
1163{
1164        struct strbuf desc = STRBUF_INIT;
1165        struct wt_status_state state;
1166        memset(&state, 0, sizeof(state));
1167        wt_status_get_state(&state, 1);
1168        if (state.rebase_in_progress ||
1169            state.rebase_interactive_in_progress)
1170                strbuf_addf(&desc, _("(no branch, rebasing %s)"),
1171                            state.branch);
1172        else if (state.bisect_in_progress)
1173                strbuf_addf(&desc, _("(no branch, bisect started on %s)"),
1174                            state.branch);
1175        else if (state.detached_from) {
1176                /* TRANSLATORS: make sure these match _("HEAD detached at ")
1177                   and _("HEAD detached from ") in wt-status.c */
1178                if (state.detached_at)
1179                        strbuf_addf(&desc, _("(HEAD detached at %s)"),
1180                                state.detached_from);
1181                else
1182                        strbuf_addf(&desc, _("(HEAD detached from %s)"),
1183                                state.detached_from);
1184        }
1185        else
1186                strbuf_addstr(&desc, _("(no branch)"));
1187        free(state.branch);
1188        free(state.onto);
1189        free(state.detached_from);
1190        return strbuf_detach(&desc, NULL);
1191}
1192
1193static const char *get_symref(struct used_atom *atom, struct ref_array_item *ref)
1194{
1195        if (!ref->symref)
1196                return "";
1197        else
1198                return show_ref(&atom->u.refname, ref->symref);
1199}
1200
1201static const char *get_refname(struct used_atom *atom, struct ref_array_item *ref)
1202{
1203        if (ref->kind & FILTER_REFS_DETACHED_HEAD)
1204                return get_head_description();
1205        return show_ref(&atom->u.refname, ref->refname);
1206}
1207
1208/*
1209 * Parse the object referred by ref, and grab needed value.
1210 */
1211static void populate_value(struct ref_array_item *ref)
1212{
1213        void *buf;
1214        struct object *obj;
1215        int eaten, i;
1216        unsigned long size;
1217        const unsigned char *tagged;
1218
1219        ref->value = xcalloc(used_atom_cnt, sizeof(struct atom_value));
1220
1221        if (need_symref && (ref->flag & REF_ISSYMREF) && !ref->symref) {
1222                unsigned char unused1[20];
1223                ref->symref = resolve_refdup(ref->refname, RESOLVE_REF_READING,
1224                                             unused1, NULL);
1225                if (!ref->symref)
1226                        ref->symref = "";
1227        }
1228
1229        /* Fill in specials first */
1230        for (i = 0; i < used_atom_cnt; i++) {
1231                struct used_atom *atom = &used_atom[i];
1232                const char *name = used_atom[i].name;
1233                struct atom_value *v = &ref->value[i];
1234                int deref = 0;
1235                const char *refname;
1236                struct branch *branch = NULL;
1237
1238                v->handler = append_atom;
1239                v->atom = atom;
1240
1241                if (*name == '*') {
1242                        deref = 1;
1243                        name++;
1244                }
1245
1246                if (starts_with(name, "refname"))
1247                        refname = get_refname(atom, ref);
1248                else if (starts_with(name, "symref"))
1249                        refname = get_symref(atom, ref);
1250                else if (starts_with(name, "upstream")) {
1251                        const char *branch_name;
1252                        /* only local branches may have an upstream */
1253                        if (!skip_prefix(ref->refname, "refs/heads/",
1254                                         &branch_name))
1255                                continue;
1256                        branch = branch_get(branch_name);
1257
1258                        refname = branch_get_upstream(branch, NULL);
1259                        if (refname)
1260                                fill_remote_ref_details(atom, refname, branch, &v->s);
1261                        continue;
1262                } else if (starts_with(name, "push")) {
1263                        const char *branch_name;
1264                        if (!skip_prefix(ref->refname, "refs/heads/",
1265                                         &branch_name))
1266                                continue;
1267                        branch = branch_get(branch_name);
1268
1269                        refname = branch_get_push(branch, NULL);
1270                        if (!refname)
1271                                continue;
1272                        fill_remote_ref_details(atom, refname, branch, &v->s);
1273                        continue;
1274                } else if (starts_with(name, "color:")) {
1275                        v->s = atom->u.color;
1276                        continue;
1277                } else if (!strcmp(name, "flag")) {
1278                        char buf[256], *cp = buf;
1279                        if (ref->flag & REF_ISSYMREF)
1280                                cp = copy_advance(cp, ",symref");
1281                        if (ref->flag & REF_ISPACKED)
1282                                cp = copy_advance(cp, ",packed");
1283                        if (cp == buf)
1284                                v->s = "";
1285                        else {
1286                                *cp = '\0';
1287                                v->s = xstrdup(buf + 1);
1288                        }
1289                        continue;
1290                } else if (!deref && grab_objectname(name, ref->objectname, v, atom)) {
1291                        continue;
1292                } else if (!strcmp(name, "HEAD")) {
1293                        const char *head;
1294                        unsigned char sha1[20];
1295
1296                        head = resolve_ref_unsafe("HEAD", RESOLVE_REF_READING,
1297                                                  sha1, NULL);
1298                        if (head && !strcmp(ref->refname, head))
1299                                v->s = "*";
1300                        else
1301                                v->s = " ";
1302                        continue;
1303                } else if (starts_with(name, "align")) {
1304                        v->handler = align_atom_handler;
1305                        continue;
1306                } else if (!strcmp(name, "end")) {
1307                        v->handler = end_atom_handler;
1308                        continue;
1309                } else if (starts_with(name, "if")) {
1310                        const char *s;
1311
1312                        if (skip_prefix(name, "if:", &s))
1313                                v->s = xstrdup(s);
1314                        v->handler = if_atom_handler;
1315                        continue;
1316                } else if (!strcmp(name, "then")) {
1317                        v->handler = then_atom_handler;
1318                        continue;
1319                } else if (!strcmp(name, "else")) {
1320                        v->handler = else_atom_handler;
1321                        continue;
1322                } else
1323                        continue;
1324
1325                if (!deref)
1326                        v->s = refname;
1327                else
1328                        v->s = xstrfmt("%s^{}", refname);
1329        }
1330
1331        for (i = 0; i < used_atom_cnt; i++) {
1332                struct atom_value *v = &ref->value[i];
1333                if (v->s == NULL)
1334                        goto need_obj;
1335        }
1336        return;
1337
1338 need_obj:
1339        buf = get_obj(ref->objectname, &obj, &size, &eaten);
1340        if (!buf)
1341                die(_("missing object %s for %s"),
1342                    sha1_to_hex(ref->objectname), ref->refname);
1343        if (!obj)
1344                die(_("parse_object_buffer failed on %s for %s"),
1345                    sha1_to_hex(ref->objectname), ref->refname);
1346
1347        grab_values(ref->value, 0, obj, buf, size);
1348        if (!eaten)
1349                free(buf);
1350
1351        /*
1352         * If there is no atom that wants to know about tagged
1353         * object, we are done.
1354         */
1355        if (!need_tagged || (obj->type != OBJ_TAG))
1356                return;
1357
1358        /*
1359         * If it is a tag object, see if we use a value that derefs
1360         * the object, and if we do grab the object it refers to.
1361         */
1362        tagged = ((struct tag *)obj)->tagged->oid.hash;
1363
1364        /*
1365         * NEEDSWORK: This derefs tag only once, which
1366         * is good to deal with chains of trust, but
1367         * is not consistent with what deref_tag() does
1368         * which peels the onion to the core.
1369         */
1370        buf = get_obj(tagged, &obj, &size, &eaten);
1371        if (!buf)
1372                die(_("missing object %s for %s"),
1373                    sha1_to_hex(tagged), ref->refname);
1374        if (!obj)
1375                die(_("parse_object_buffer failed on %s for %s"),
1376                    sha1_to_hex(tagged), ref->refname);
1377        grab_values(ref->value, 1, obj, buf, size);
1378        if (!eaten)
1379                free(buf);
1380}
1381
1382/*
1383 * Given a ref, return the value for the atom.  This lazily gets value
1384 * out of the object by calling populate value.
1385 */
1386static void get_ref_atom_value(struct ref_array_item *ref, int atom, struct atom_value **v)
1387{
1388        if (!ref->value) {
1389                populate_value(ref);
1390                fill_missing_values(ref->value);
1391        }
1392        *v = &ref->value[atom];
1393}
1394
1395enum contains_result {
1396        CONTAINS_UNKNOWN = -1,
1397        CONTAINS_NO = 0,
1398        CONTAINS_YES = 1
1399};
1400
1401/*
1402 * Mimicking the real stack, this stack lives on the heap, avoiding stack
1403 * overflows.
1404 *
1405 * At each recursion step, the stack items points to the commits whose
1406 * ancestors are to be inspected.
1407 */
1408struct contains_stack {
1409        int nr, alloc;
1410        struct contains_stack_entry {
1411                struct commit *commit;
1412                struct commit_list *parents;
1413        } *contains_stack;
1414};
1415
1416static int in_commit_list(const struct commit_list *want, struct commit *c)
1417{
1418        for (; want; want = want->next)
1419                if (!oidcmp(&want->item->object.oid, &c->object.oid))
1420                        return 1;
1421        return 0;
1422}
1423
1424/*
1425 * Test whether the candidate or one of its parents is contained in the list.
1426 * Do not recurse to find out, though, but return -1 if inconclusive.
1427 */
1428static enum contains_result contains_test(struct commit *candidate,
1429                            const struct commit_list *want)
1430{
1431        /* was it previously marked as containing a want commit? */
1432        if (candidate->object.flags & TMP_MARK)
1433                return 1;
1434        /* or marked as not possibly containing a want commit? */
1435        if (candidate->object.flags & UNINTERESTING)
1436                return 0;
1437        /* or are we it? */
1438        if (in_commit_list(want, candidate)) {
1439                candidate->object.flags |= TMP_MARK;
1440                return 1;
1441        }
1442
1443        if (parse_commit(candidate) < 0)
1444                return 0;
1445
1446        return -1;
1447}
1448
1449static void push_to_contains_stack(struct commit *candidate, struct contains_stack *contains_stack)
1450{
1451        ALLOC_GROW(contains_stack->contains_stack, contains_stack->nr + 1, contains_stack->alloc);
1452        contains_stack->contains_stack[contains_stack->nr].commit = candidate;
1453        contains_stack->contains_stack[contains_stack->nr++].parents = candidate->parents;
1454}
1455
1456static enum contains_result contains_tag_algo(struct commit *candidate,
1457                const struct commit_list *want)
1458{
1459        struct contains_stack contains_stack = { 0, 0, NULL };
1460        int result = contains_test(candidate, want);
1461
1462        if (result != CONTAINS_UNKNOWN)
1463                return result;
1464
1465        push_to_contains_stack(candidate, &contains_stack);
1466        while (contains_stack.nr) {
1467                struct contains_stack_entry *entry = &contains_stack.contains_stack[contains_stack.nr - 1];
1468                struct commit *commit = entry->commit;
1469                struct commit_list *parents = entry->parents;
1470
1471                if (!parents) {
1472                        commit->object.flags |= UNINTERESTING;
1473                        contains_stack.nr--;
1474                }
1475                /*
1476                 * If we just popped the stack, parents->item has been marked,
1477                 * therefore contains_test will return a meaningful 0 or 1.
1478                 */
1479                else switch (contains_test(parents->item, want)) {
1480                case CONTAINS_YES:
1481                        commit->object.flags |= TMP_MARK;
1482                        contains_stack.nr--;
1483                        break;
1484                case CONTAINS_NO:
1485                        entry->parents = parents->next;
1486                        break;
1487                case CONTAINS_UNKNOWN:
1488                        push_to_contains_stack(parents->item, &contains_stack);
1489                        break;
1490                }
1491        }
1492        free(contains_stack.contains_stack);
1493        return contains_test(candidate, want);
1494}
1495
1496static int commit_contains(struct ref_filter *filter, struct commit *commit)
1497{
1498        if (filter->with_commit_tag_algo)
1499                return contains_tag_algo(commit, filter->with_commit);
1500        return is_descendant_of(commit, filter->with_commit);
1501}
1502
1503/*
1504 * Return 1 if the refname matches one of the patterns, otherwise 0.
1505 * A pattern can be a literal prefix (e.g. a refname "refs/heads/master"
1506 * matches a pattern "refs/heads/mas") or a wildcard (e.g. the same ref
1507 * matches "refs/heads/mas*", too).
1508 */
1509static int match_pattern(const struct ref_filter *filter, const char *refname)
1510{
1511        const char **patterns = filter->name_patterns;
1512        unsigned flags = 0;
1513
1514        if (filter->ignore_case)
1515                flags |= WM_CASEFOLD;
1516
1517        /*
1518         * When no '--format' option is given we need to skip the prefix
1519         * for matching refs of tags and branches.
1520         */
1521        (void)(skip_prefix(refname, "refs/tags/", &refname) ||
1522               skip_prefix(refname, "refs/heads/", &refname) ||
1523               skip_prefix(refname, "refs/remotes/", &refname) ||
1524               skip_prefix(refname, "refs/", &refname));
1525
1526        for (; *patterns; patterns++) {
1527                if (!wildmatch(*patterns, refname, flags, NULL))
1528                        return 1;
1529        }
1530        return 0;
1531}
1532
1533/*
1534 * Return 1 if the refname matches one of the patterns, otherwise 0.
1535 * A pattern can be path prefix (e.g. a refname "refs/heads/master"
1536 * matches a pattern "refs/heads/" but not "refs/heads/m") or a
1537 * wildcard (e.g. the same ref matches "refs/heads/m*", too).
1538 */
1539static int match_name_as_path(const struct ref_filter *filter, const char *refname)
1540{
1541        const char **pattern = filter->name_patterns;
1542        int namelen = strlen(refname);
1543        unsigned flags = WM_PATHNAME;
1544
1545        if (filter->ignore_case)
1546                flags |= WM_CASEFOLD;
1547
1548        for (; *pattern; pattern++) {
1549                const char *p = *pattern;
1550                int plen = strlen(p);
1551
1552                if ((plen <= namelen) &&
1553                    !strncmp(refname, p, plen) &&
1554                    (refname[plen] == '\0' ||
1555                     refname[plen] == '/' ||
1556                     p[plen-1] == '/'))
1557                        return 1;
1558                if (!wildmatch(p, refname, WM_PATHNAME, NULL))
1559                        return 1;
1560        }
1561        return 0;
1562}
1563
1564/* Return 1 if the refname matches one of the patterns, otherwise 0. */
1565static int filter_pattern_match(struct ref_filter *filter, const char *refname)
1566{
1567        if (!*filter->name_patterns)
1568                return 1; /* No pattern always matches */
1569        if (filter->match_as_path)
1570                return match_name_as_path(filter, refname);
1571        return match_pattern(filter, refname);
1572}
1573
1574/*
1575 * Given a ref (sha1, refname), check if the ref belongs to the array
1576 * of sha1s. If the given ref is a tag, check if the given tag points
1577 * at one of the sha1s in the given sha1 array.
1578 * the given sha1_array.
1579 * NEEDSWORK:
1580 * 1. Only a single level of inderection is obtained, we might want to
1581 * change this to account for multiple levels (e.g. annotated tags
1582 * pointing to annotated tags pointing to a commit.)
1583 * 2. As the refs are cached we might know what refname peels to without
1584 * the need to parse the object via parse_object(). peel_ref() might be a
1585 * more efficient alternative to obtain the pointee.
1586 */
1587static const unsigned char *match_points_at(struct sha1_array *points_at,
1588                                            const unsigned char *sha1,
1589                                            const char *refname)
1590{
1591        const unsigned char *tagged_sha1 = NULL;
1592        struct object *obj;
1593
1594        if (sha1_array_lookup(points_at, sha1) >= 0)
1595                return sha1;
1596        obj = parse_object(sha1);
1597        if (!obj)
1598                die(_("malformed object at '%s'"), refname);
1599        if (obj->type == OBJ_TAG)
1600                tagged_sha1 = ((struct tag *)obj)->tagged->oid.hash;
1601        if (tagged_sha1 && sha1_array_lookup(points_at, tagged_sha1) >= 0)
1602                return tagged_sha1;
1603        return NULL;
1604}
1605
1606/* Allocate space for a new ref_array_item and copy the objectname and flag to it */
1607static struct ref_array_item *new_ref_array_item(const char *refname,
1608                                                 const unsigned char *objectname,
1609                                                 int flag)
1610{
1611        struct ref_array_item *ref;
1612        FLEX_ALLOC_STR(ref, refname, refname);
1613        hashcpy(ref->objectname, objectname);
1614        ref->flag = flag;
1615
1616        return ref;
1617}
1618
1619static int filter_ref_kind(struct ref_filter *filter, const char *refname)
1620{
1621        unsigned int i;
1622
1623        static struct {
1624                const char *prefix;
1625                unsigned int kind;
1626        } ref_kind[] = {
1627                { "refs/heads/" , FILTER_REFS_BRANCHES },
1628                { "refs/remotes/" , FILTER_REFS_REMOTES },
1629                { "refs/tags/", FILTER_REFS_TAGS}
1630        };
1631
1632        if (filter->kind == FILTER_REFS_BRANCHES ||
1633            filter->kind == FILTER_REFS_REMOTES ||
1634            filter->kind == FILTER_REFS_TAGS)
1635                return filter->kind;
1636        else if (!strcmp(refname, "HEAD"))
1637                return FILTER_REFS_DETACHED_HEAD;
1638
1639        for (i = 0; i < ARRAY_SIZE(ref_kind); i++) {
1640                if (starts_with(refname, ref_kind[i].prefix))
1641                        return ref_kind[i].kind;
1642        }
1643
1644        return FILTER_REFS_OTHERS;
1645}
1646
1647/*
1648 * A call-back given to for_each_ref().  Filter refs and keep them for
1649 * later object processing.
1650 */
1651static int ref_filter_handler(const char *refname, const struct object_id *oid, int flag, void *cb_data)
1652{
1653        struct ref_filter_cbdata *ref_cbdata = cb_data;
1654        struct ref_filter *filter = ref_cbdata->filter;
1655        struct ref_array_item *ref;
1656        struct commit *commit = NULL;
1657        unsigned int kind;
1658
1659        if (flag & REF_BAD_NAME) {
1660                warning(_("ignoring ref with broken name %s"), refname);
1661                return 0;
1662        }
1663
1664        if (flag & REF_ISBROKEN) {
1665                warning(_("ignoring broken ref %s"), refname);
1666                return 0;
1667        }
1668
1669        /* Obtain the current ref kind from filter_ref_kind() and ignore unwanted refs. */
1670        kind = filter_ref_kind(filter, refname);
1671        if (!(kind & filter->kind))
1672                return 0;
1673
1674        if (!filter_pattern_match(filter, refname))
1675                return 0;
1676
1677        if (filter->points_at.nr && !match_points_at(&filter->points_at, oid->hash, refname))
1678                return 0;
1679
1680        /*
1681         * A merge filter is applied on refs pointing to commits. Hence
1682         * obtain the commit using the 'oid' available and discard all
1683         * non-commits early. The actual filtering is done later.
1684         */
1685        if (filter->merge_commit || filter->with_commit || filter->verbose) {
1686                commit = lookup_commit_reference_gently(oid->hash, 1);
1687                if (!commit)
1688                        return 0;
1689                /* We perform the filtering for the '--contains' option */
1690                if (filter->with_commit &&
1691                    !commit_contains(filter, commit))
1692                        return 0;
1693        }
1694
1695        /*
1696         * We do not open the object yet; sort may only need refname
1697         * to do its job and the resulting list may yet to be pruned
1698         * by maxcount logic.
1699         */
1700        ref = new_ref_array_item(refname, oid->hash, flag);
1701        ref->commit = commit;
1702
1703        REALLOC_ARRAY(ref_cbdata->array->items, ref_cbdata->array->nr + 1);
1704        ref_cbdata->array->items[ref_cbdata->array->nr++] = ref;
1705        ref->kind = kind;
1706        return 0;
1707}
1708
1709/*  Free memory allocated for a ref_array_item */
1710static void free_array_item(struct ref_array_item *item)
1711{
1712        free((char *)item->symref);
1713        free(item);
1714}
1715
1716/* Free all memory allocated for ref_array */
1717void ref_array_clear(struct ref_array *array)
1718{
1719        int i;
1720
1721        for (i = 0; i < array->nr; i++)
1722                free_array_item(array->items[i]);
1723        free(array->items);
1724        array->items = NULL;
1725        array->nr = array->alloc = 0;
1726}
1727
1728static void do_merge_filter(struct ref_filter_cbdata *ref_cbdata)
1729{
1730        struct rev_info revs;
1731        int i, old_nr;
1732        struct ref_filter *filter = ref_cbdata->filter;
1733        struct ref_array *array = ref_cbdata->array;
1734        struct commit **to_clear = xcalloc(sizeof(struct commit *), array->nr);
1735
1736        init_revisions(&revs, NULL);
1737
1738        for (i = 0; i < array->nr; i++) {
1739                struct ref_array_item *item = array->items[i];
1740                add_pending_object(&revs, &item->commit->object, item->refname);
1741                to_clear[i] = item->commit;
1742        }
1743
1744        filter->merge_commit->object.flags |= UNINTERESTING;
1745        add_pending_object(&revs, &filter->merge_commit->object, "");
1746
1747        revs.limited = 1;
1748        if (prepare_revision_walk(&revs))
1749                die(_("revision walk setup failed"));
1750
1751        old_nr = array->nr;
1752        array->nr = 0;
1753
1754        for (i = 0; i < old_nr; i++) {
1755                struct ref_array_item *item = array->items[i];
1756                struct commit *commit = item->commit;
1757
1758                int is_merged = !!(commit->object.flags & UNINTERESTING);
1759
1760                if (is_merged == (filter->merge == REF_FILTER_MERGED_INCLUDE))
1761                        array->items[array->nr++] = array->items[i];
1762                else
1763                        free_array_item(item);
1764        }
1765
1766        for (i = 0; i < old_nr; i++)
1767                clear_commit_marks(to_clear[i], ALL_REV_FLAGS);
1768        clear_commit_marks(filter->merge_commit, ALL_REV_FLAGS);
1769        free(to_clear);
1770}
1771
1772/*
1773 * API for filtering a set of refs. Based on the type of refs the user
1774 * has requested, we iterate through those refs and apply filters
1775 * as per the given ref_filter structure and finally store the
1776 * filtered refs in the ref_array structure.
1777 */
1778int filter_refs(struct ref_array *array, struct ref_filter *filter, unsigned int type)
1779{
1780        struct ref_filter_cbdata ref_cbdata;
1781        int ret = 0;
1782        unsigned int broken = 0;
1783
1784        ref_cbdata.array = array;
1785        ref_cbdata.filter = filter;
1786
1787        if (type & FILTER_REFS_INCLUDE_BROKEN)
1788                broken = 1;
1789        filter->kind = type & FILTER_REFS_KIND_MASK;
1790
1791        /*  Simple per-ref filtering */
1792        if (!filter->kind)
1793                die("filter_refs: invalid type");
1794        else {
1795                /*
1796                 * For common cases where we need only branches or remotes or tags,
1797                 * we only iterate through those refs. If a mix of refs is needed,
1798                 * we iterate over all refs and filter out required refs with the help
1799                 * of filter_ref_kind().
1800                 */
1801                if (filter->kind == FILTER_REFS_BRANCHES)
1802                        ret = for_each_fullref_in("refs/heads/", ref_filter_handler, &ref_cbdata, broken);
1803                else if (filter->kind == FILTER_REFS_REMOTES)
1804                        ret = for_each_fullref_in("refs/remotes/", ref_filter_handler, &ref_cbdata, broken);
1805                else if (filter->kind == FILTER_REFS_TAGS)
1806                        ret = for_each_fullref_in("refs/tags/", ref_filter_handler, &ref_cbdata, broken);
1807                else if (filter->kind & FILTER_REFS_ALL)
1808                        ret = for_each_fullref_in("", ref_filter_handler, &ref_cbdata, broken);
1809                if (!ret && (filter->kind & FILTER_REFS_DETACHED_HEAD))
1810                        head_ref(ref_filter_handler, &ref_cbdata);
1811        }
1812
1813
1814        /*  Filters that need revision walking */
1815        if (filter->merge_commit)
1816                do_merge_filter(&ref_cbdata);
1817
1818        return ret;
1819}
1820
1821static int cmp_ref_sorting(struct ref_sorting *s, struct ref_array_item *a, struct ref_array_item *b)
1822{
1823        struct atom_value *va, *vb;
1824        int cmp;
1825        cmp_type cmp_type = used_atom[s->atom].type;
1826        int (*cmp_fn)(const char *, const char *);
1827
1828        get_ref_atom_value(a, s->atom, &va);
1829        get_ref_atom_value(b, s->atom, &vb);
1830        cmp_fn = s->ignore_case ? strcasecmp : strcmp;
1831        if (s->version)
1832                cmp = versioncmp(va->s, vb->s);
1833        else if (cmp_type == FIELD_STR)
1834                cmp = cmp_fn(va->s, vb->s);
1835        else {
1836                if (va->ul < vb->ul)
1837                        cmp = -1;
1838                else if (va->ul == vb->ul)
1839                        cmp = cmp_fn(a->refname, b->refname);
1840                else
1841                        cmp = 1;
1842        }
1843
1844        return (s->reverse) ? -cmp : cmp;
1845}
1846
1847static struct ref_sorting *ref_sorting;
1848static int compare_refs(const void *a_, const void *b_)
1849{
1850        struct ref_array_item *a = *((struct ref_array_item **)a_);
1851        struct ref_array_item *b = *((struct ref_array_item **)b_);
1852        struct ref_sorting *s;
1853
1854        for (s = ref_sorting; s; s = s->next) {
1855                int cmp = cmp_ref_sorting(s, a, b);
1856                if (cmp)
1857                        return cmp;
1858        }
1859        return 0;
1860}
1861
1862void ref_array_sort(struct ref_sorting *sorting, struct ref_array *array)
1863{
1864        ref_sorting = sorting;
1865        QSORT(array->items, array->nr, compare_refs);
1866}
1867
1868static void append_literal(const char *cp, const char *ep, struct ref_formatting_state *state)
1869{
1870        struct strbuf *s = &state->stack->output;
1871
1872        while (*cp && (!ep || cp < ep)) {
1873                if (*cp == '%') {
1874                        if (cp[1] == '%')
1875                                cp++;
1876                        else {
1877                                int ch = hex2chr(cp + 1);
1878                                if (0 <= ch) {
1879                                        strbuf_addch(s, ch);
1880                                        cp += 3;
1881                                        continue;
1882                                }
1883                        }
1884                }
1885                strbuf_addch(s, *cp);
1886                cp++;
1887        }
1888}
1889
1890void format_ref_array_item(struct ref_array_item *info, const char *format,
1891                           int quote_style, struct strbuf *final_buf)
1892{
1893        const char *cp, *sp, *ep;
1894        struct ref_formatting_state state = REF_FORMATTING_STATE_INIT;
1895
1896        state.quote_style = quote_style;
1897        push_stack_element(&state.stack);
1898
1899        for (cp = format; *cp && (sp = find_next(cp)); cp = ep + 1) {
1900                struct atom_value *atomv;
1901
1902                ep = strchr(sp, ')');
1903                if (cp < sp)
1904                        append_literal(cp, sp, &state);
1905                get_ref_atom_value(info, parse_ref_filter_atom(sp + 2, ep), &atomv);
1906                atomv->handler(atomv, &state);
1907        }
1908        if (*cp) {
1909                sp = cp + strlen(cp);
1910                append_literal(cp, sp, &state);
1911        }
1912        if (need_color_reset_at_eol) {
1913                struct atom_value resetv;
1914                char color[COLOR_MAXLEN] = "";
1915
1916                if (color_parse("reset", color) < 0)
1917                        die("BUG: couldn't parse 'reset' as a color");
1918                resetv.s = color;
1919                append_atom(&resetv, &state);
1920        }
1921        if (state.stack->prev)
1922                die(_("format: %%(end) atom missing"));
1923        strbuf_addbuf(final_buf, &state.stack->output);
1924        pop_stack_element(&state.stack);
1925}
1926
1927void show_ref_array_item(struct ref_array_item *info, const char *format, int quote_style)
1928{
1929        struct strbuf final_buf = STRBUF_INIT;
1930
1931        format_ref_array_item(info, format, quote_style, &final_buf);
1932        fwrite(final_buf.buf, 1, final_buf.len, stdout);
1933        strbuf_release(&final_buf);
1934        putchar('\n');
1935}
1936
1937/*  If no sorting option is given, use refname to sort as default */
1938struct ref_sorting *ref_default_sorting(void)
1939{
1940        static const char cstr_name[] = "refname";
1941
1942        struct ref_sorting *sorting = xcalloc(1, sizeof(*sorting));
1943
1944        sorting->next = NULL;
1945        sorting->atom = parse_ref_filter_atom(cstr_name, cstr_name + strlen(cstr_name));
1946        return sorting;
1947}
1948
1949int parse_opt_ref_sorting(const struct option *opt, const char *arg, int unset)
1950{
1951        struct ref_sorting **sorting_tail = opt->value;
1952        struct ref_sorting *s;
1953        int len;
1954
1955        if (!arg) /* should --no-sort void the list ? */
1956                return -1;
1957
1958        s = xcalloc(1, sizeof(*s));
1959        s->next = *sorting_tail;
1960        *sorting_tail = s;
1961
1962        if (*arg == '-') {
1963                s->reverse = 1;
1964                arg++;
1965        }
1966        if (skip_prefix(arg, "version:", &arg) ||
1967            skip_prefix(arg, "v:", &arg))
1968                s->version = 1;
1969        len = strlen(arg);
1970        s->atom = parse_ref_filter_atom(arg, arg+len);
1971        return 0;
1972}
1973
1974int parse_opt_merge_filter(const struct option *opt, const char *arg, int unset)
1975{
1976        struct ref_filter *rf = opt->value;
1977        unsigned char sha1[20];
1978
1979        rf->merge = starts_with(opt->long_name, "no")
1980                ? REF_FILTER_MERGED_OMIT
1981                : REF_FILTER_MERGED_INCLUDE;
1982
1983        if (get_sha1(arg, sha1))
1984                die(_("malformed object name %s"), arg);
1985
1986        rf->merge_commit = lookup_commit_reference_gently(sha1, 0);
1987        if (!rf->merge_commit)
1988                return opterror(opt, "must point to a commit", 0);
1989
1990        return 0;
1991}