Andrew's git / gitweb.git / grep.c
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grep.con commit Update draft release notes to 1.8.4 (911011a)
   1#include "cache.h"
   2#include "grep.h"
   3#include "userdiff.h"
   4#include "xdiff-interface.h"
   5
   6static int grep_source_load(struct grep_source *gs);
   7static int grep_source_is_binary(struct grep_source *gs);
   8
   9static struct grep_opt grep_defaults;
  10
  11/*
  12 * Initialize the grep_defaults template with hardcoded defaults.
  13 * We could let the compiler do this, but without C99 initializers
  14 * the code gets unwieldy and unreadable, so...
  15 */
  16void init_grep_defaults(void)
  17{
  18        struct grep_opt *opt = &grep_defaults;
  19        static int run_once;
  20
  21        if (run_once)
  22                return;
  23        run_once++;
  24
  25        memset(opt, 0, sizeof(*opt));
  26        opt->relative = 1;
  27        opt->pathname = 1;
  28        opt->regflags = REG_NEWLINE;
  29        opt->max_depth = -1;
  30        opt->pattern_type_option = GREP_PATTERN_TYPE_UNSPECIFIED;
  31        opt->extended_regexp_option = 0;
  32        strcpy(opt->color_context, "");
  33        strcpy(opt->color_filename, "");
  34        strcpy(opt->color_function, "");
  35        strcpy(opt->color_lineno, "");
  36        strcpy(opt->color_match, GIT_COLOR_BOLD_RED);
  37        strcpy(opt->color_selected, "");
  38        strcpy(opt->color_sep, GIT_COLOR_CYAN);
  39        opt->color = -1;
  40}
  41
  42static int parse_pattern_type_arg(const char *opt, const char *arg)
  43{
  44        if (!strcmp(arg, "default"))
  45                return GREP_PATTERN_TYPE_UNSPECIFIED;
  46        else if (!strcmp(arg, "basic"))
  47                return GREP_PATTERN_TYPE_BRE;
  48        else if (!strcmp(arg, "extended"))
  49                return GREP_PATTERN_TYPE_ERE;
  50        else if (!strcmp(arg, "fixed"))
  51                return GREP_PATTERN_TYPE_FIXED;
  52        else if (!strcmp(arg, "perl"))
  53                return GREP_PATTERN_TYPE_PCRE;
  54        die("bad %s argument: %s", opt, arg);
  55}
  56
  57/*
  58 * Read the configuration file once and store it in
  59 * the grep_defaults template.
  60 */
  61int grep_config(const char *var, const char *value, void *cb)
  62{
  63        struct grep_opt *opt = &grep_defaults;
  64        char *color = NULL;
  65
  66        if (userdiff_config(var, value) < 0)
  67                return -1;
  68
  69        if (!strcmp(var, "grep.extendedregexp")) {
  70                if (git_config_bool(var, value))
  71                        opt->extended_regexp_option = 1;
  72                else
  73                        opt->extended_regexp_option = 0;
  74                return 0;
  75        }
  76
  77        if (!strcmp(var, "grep.patterntype")) {
  78                opt->pattern_type_option = parse_pattern_type_arg(var, value);
  79                return 0;
  80        }
  81
  82        if (!strcmp(var, "grep.linenumber")) {
  83                opt->linenum = git_config_bool(var, value);
  84                return 0;
  85        }
  86
  87        if (!strcmp(var, "color.grep"))
  88                opt->color = git_config_colorbool(var, value);
  89        else if (!strcmp(var, "color.grep.context"))
  90                color = opt->color_context;
  91        else if (!strcmp(var, "color.grep.filename"))
  92                color = opt->color_filename;
  93        else if (!strcmp(var, "color.grep.function"))
  94                color = opt->color_function;
  95        else if (!strcmp(var, "color.grep.linenumber"))
  96                color = opt->color_lineno;
  97        else if (!strcmp(var, "color.grep.match"))
  98                color = opt->color_match;
  99        else if (!strcmp(var, "color.grep.selected"))
 100                color = opt->color_selected;
 101        else if (!strcmp(var, "color.grep.separator"))
 102                color = opt->color_sep;
 103
 104        if (color) {
 105                if (!value)
 106                        return config_error_nonbool(var);
 107                color_parse(value, var, color);
 108        }
 109        return 0;
 110}
 111
 112/*
 113 * Initialize one instance of grep_opt and copy the
 114 * default values from the template we read the configuration
 115 * information in an earlier call to git_config(grep_config).
 116 */
 117void grep_init(struct grep_opt *opt, const char *prefix)
 118{
 119        struct grep_opt *def = &grep_defaults;
 120
 121        memset(opt, 0, sizeof(*opt));
 122        opt->prefix = prefix;
 123        opt->prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
 124        opt->pattern_tail = &opt->pattern_list;
 125        opt->header_tail = &opt->header_list;
 126
 127        opt->color = def->color;
 128        opt->extended_regexp_option = def->extended_regexp_option;
 129        opt->pattern_type_option = def->pattern_type_option;
 130        opt->linenum = def->linenum;
 131        opt->max_depth = def->max_depth;
 132        opt->pathname = def->pathname;
 133        opt->regflags = def->regflags;
 134        opt->relative = def->relative;
 135
 136        strcpy(opt->color_context, def->color_context);
 137        strcpy(opt->color_filename, def->color_filename);
 138        strcpy(opt->color_function, def->color_function);
 139        strcpy(opt->color_lineno, def->color_lineno);
 140        strcpy(opt->color_match, def->color_match);
 141        strcpy(opt->color_selected, def->color_selected);
 142        strcpy(opt->color_sep, def->color_sep);
 143}
 144
 145void grep_commit_pattern_type(enum grep_pattern_type pattern_type, struct grep_opt *opt)
 146{
 147        if (pattern_type != GREP_PATTERN_TYPE_UNSPECIFIED)
 148                grep_set_pattern_type_option(pattern_type, opt);
 149        else if (opt->pattern_type_option != GREP_PATTERN_TYPE_UNSPECIFIED)
 150                grep_set_pattern_type_option(opt->pattern_type_option, opt);
 151        else if (opt->extended_regexp_option)
 152                grep_set_pattern_type_option(GREP_PATTERN_TYPE_ERE, opt);
 153}
 154
 155void grep_set_pattern_type_option(enum grep_pattern_type pattern_type, struct grep_opt *opt)
 156{
 157        switch (pattern_type) {
 158        case GREP_PATTERN_TYPE_UNSPECIFIED:
 159                /* fall through */
 160
 161        case GREP_PATTERN_TYPE_BRE:
 162                opt->fixed = 0;
 163                opt->pcre = 0;
 164                opt->regflags &= ~REG_EXTENDED;
 165                break;
 166
 167        case GREP_PATTERN_TYPE_ERE:
 168                opt->fixed = 0;
 169                opt->pcre = 0;
 170                opt->regflags |= REG_EXTENDED;
 171                break;
 172
 173        case GREP_PATTERN_TYPE_FIXED:
 174                opt->fixed = 1;
 175                opt->pcre = 0;
 176                opt->regflags &= ~REG_EXTENDED;
 177                break;
 178
 179        case GREP_PATTERN_TYPE_PCRE:
 180                opt->fixed = 0;
 181                opt->pcre = 1;
 182                opt->regflags &= ~REG_EXTENDED;
 183                break;
 184        }
 185}
 186
 187static struct grep_pat *create_grep_pat(const char *pat, size_t patlen,
 188                                        const char *origin, int no,
 189                                        enum grep_pat_token t,
 190                                        enum grep_header_field field)
 191{
 192        struct grep_pat *p = xcalloc(1, sizeof(*p));
 193        p->pattern = xmemdupz(pat, patlen);
 194        p->patternlen = patlen;
 195        p->origin = origin;
 196        p->no = no;
 197        p->token = t;
 198        p->field = field;
 199        return p;
 200}
 201
 202static void do_append_grep_pat(struct grep_pat ***tail, struct grep_pat *p)
 203{
 204        **tail = p;
 205        *tail = &p->next;
 206        p->next = NULL;
 207
 208        switch (p->token) {
 209        case GREP_PATTERN: /* atom */
 210        case GREP_PATTERN_HEAD:
 211        case GREP_PATTERN_BODY:
 212                for (;;) {
 213                        struct grep_pat *new_pat;
 214                        size_t len = 0;
 215                        char *cp = p->pattern + p->patternlen, *nl = NULL;
 216                        while (++len <= p->patternlen) {
 217                                if (*(--cp) == '\n') {
 218                                        nl = cp;
 219                                        break;
 220                                }
 221                        }
 222                        if (!nl)
 223                                break;
 224                        new_pat = create_grep_pat(nl + 1, len - 1, p->origin,
 225                                                  p->no, p->token, p->field);
 226                        new_pat->next = p->next;
 227                        if (!p->next)
 228                                *tail = &new_pat->next;
 229                        p->next = new_pat;
 230                        *nl = '\0';
 231                        p->patternlen -= len;
 232                }
 233                break;
 234        default:
 235                break;
 236        }
 237}
 238
 239void append_header_grep_pattern(struct grep_opt *opt,
 240                                enum grep_header_field field, const char *pat)
 241{
 242        struct grep_pat *p = create_grep_pat(pat, strlen(pat), "header", 0,
 243                                             GREP_PATTERN_HEAD, field);
 244        if (field == GREP_HEADER_REFLOG)
 245                opt->use_reflog_filter = 1;
 246        do_append_grep_pat(&opt->header_tail, p);
 247}
 248
 249void append_grep_pattern(struct grep_opt *opt, const char *pat,
 250                         const char *origin, int no, enum grep_pat_token t)
 251{
 252        append_grep_pat(opt, pat, strlen(pat), origin, no, t);
 253}
 254
 255void append_grep_pat(struct grep_opt *opt, const char *pat, size_t patlen,
 256                     const char *origin, int no, enum grep_pat_token t)
 257{
 258        struct grep_pat *p = create_grep_pat(pat, patlen, origin, no, t, 0);
 259        do_append_grep_pat(&opt->pattern_tail, p);
 260}
 261
 262struct grep_opt *grep_opt_dup(const struct grep_opt *opt)
 263{
 264        struct grep_pat *pat;
 265        struct grep_opt *ret = xmalloc(sizeof(struct grep_opt));
 266        *ret = *opt;
 267
 268        ret->pattern_list = NULL;
 269        ret->pattern_tail = &ret->pattern_list;
 270
 271        for(pat = opt->pattern_list; pat != NULL; pat = pat->next)
 272        {
 273                if(pat->token == GREP_PATTERN_HEAD)
 274                        append_header_grep_pattern(ret, pat->field,
 275                                                   pat->pattern);
 276                else
 277                        append_grep_pat(ret, pat->pattern, pat->patternlen,
 278                                        pat->origin, pat->no, pat->token);
 279        }
 280
 281        return ret;
 282}
 283
 284static NORETURN void compile_regexp_failed(const struct grep_pat *p,
 285                const char *error)
 286{
 287        char where[1024];
 288
 289        if (p->no)
 290                sprintf(where, "In '%s' at %d, ", p->origin, p->no);
 291        else if (p->origin)
 292                sprintf(where, "%s, ", p->origin);
 293        else
 294                where[0] = 0;
 295
 296        die("%s'%s': %s", where, p->pattern, error);
 297}
 298
 299#ifdef USE_LIBPCRE
 300static void compile_pcre_regexp(struct grep_pat *p, const struct grep_opt *opt)
 301{
 302        const char *error;
 303        int erroffset;
 304        int options = PCRE_MULTILINE;
 305
 306        if (opt->ignore_case)
 307                options |= PCRE_CASELESS;
 308
 309        p->pcre_regexp = pcre_compile(p->pattern, options, &error, &erroffset,
 310                        NULL);
 311        if (!p->pcre_regexp)
 312                compile_regexp_failed(p, error);
 313
 314        p->pcre_extra_info = pcre_study(p->pcre_regexp, 0, &error);
 315        if (!p->pcre_extra_info && error)
 316                die("%s", error);
 317}
 318
 319static int pcrematch(struct grep_pat *p, const char *line, const char *eol,
 320                regmatch_t *match, int eflags)
 321{
 322        int ovector[30], ret, flags = 0;
 323
 324        if (eflags & REG_NOTBOL)
 325                flags |= PCRE_NOTBOL;
 326
 327        ret = pcre_exec(p->pcre_regexp, p->pcre_extra_info, line, eol - line,
 328                        0, flags, ovector, ARRAY_SIZE(ovector));
 329        if (ret < 0 && ret != PCRE_ERROR_NOMATCH)
 330                die("pcre_exec failed with error code %d", ret);
 331        if (ret > 0) {
 332                ret = 0;
 333                match->rm_so = ovector[0];
 334                match->rm_eo = ovector[1];
 335        }
 336
 337        return ret;
 338}
 339
 340static void free_pcre_regexp(struct grep_pat *p)
 341{
 342        pcre_free(p->pcre_regexp);
 343        pcre_free(p->pcre_extra_info);
 344}
 345#else /* !USE_LIBPCRE */
 346static void compile_pcre_regexp(struct grep_pat *p, const struct grep_opt *opt)
 347{
 348        die("cannot use Perl-compatible regexes when not compiled with USE_LIBPCRE");
 349}
 350
 351static int pcrematch(struct grep_pat *p, const char *line, const char *eol,
 352                regmatch_t *match, int eflags)
 353{
 354        return 1;
 355}
 356
 357static void free_pcre_regexp(struct grep_pat *p)
 358{
 359}
 360#endif /* !USE_LIBPCRE */
 361
 362static int is_fixed(const char *s, size_t len)
 363{
 364        size_t i;
 365
 366        /* regcomp cannot accept patterns with NULs so we
 367         * consider any pattern containing a NUL fixed.
 368         */
 369        if (memchr(s, 0, len))
 370                return 1;
 371
 372        for (i = 0; i < len; i++) {
 373                if (is_regex_special(s[i]))
 374                        return 0;
 375        }
 376
 377        return 1;
 378}
 379
 380static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
 381{
 382        int err;
 383
 384        p->word_regexp = opt->word_regexp;
 385        p->ignore_case = opt->ignore_case;
 386
 387        if (opt->fixed || is_fixed(p->pattern, p->patternlen))
 388                p->fixed = 1;
 389        else
 390                p->fixed = 0;
 391
 392        if (p->fixed) {
 393                if (opt->regflags & REG_ICASE || p->ignore_case)
 394                        p->kws = kwsalloc(tolower_trans_tbl);
 395                else
 396                        p->kws = kwsalloc(NULL);
 397                kwsincr(p->kws, p->pattern, p->patternlen);
 398                kwsprep(p->kws);
 399                return;
 400        }
 401
 402        if (opt->pcre) {
 403                compile_pcre_regexp(p, opt);
 404                return;
 405        }
 406
 407        err = regcomp(&p->regexp, p->pattern, opt->regflags);
 408        if (err) {
 409                char errbuf[1024];
 410                regerror(err, &p->regexp, errbuf, 1024);
 411                regfree(&p->regexp);
 412                compile_regexp_failed(p, errbuf);
 413        }
 414}
 415
 416static struct grep_expr *compile_pattern_or(struct grep_pat **);
 417static struct grep_expr *compile_pattern_atom(struct grep_pat **list)
 418{
 419        struct grep_pat *p;
 420        struct grep_expr *x;
 421
 422        p = *list;
 423        if (!p)
 424                return NULL;
 425        switch (p->token) {
 426        case GREP_PATTERN: /* atom */
 427        case GREP_PATTERN_HEAD:
 428        case GREP_PATTERN_BODY:
 429                x = xcalloc(1, sizeof (struct grep_expr));
 430                x->node = GREP_NODE_ATOM;
 431                x->u.atom = p;
 432                *list = p->next;
 433                return x;
 434        case GREP_OPEN_PAREN:
 435                *list = p->next;
 436                x = compile_pattern_or(list);
 437                if (!*list || (*list)->token != GREP_CLOSE_PAREN)
 438                        die("unmatched parenthesis");
 439                *list = (*list)->next;
 440                return x;
 441        default:
 442                return NULL;
 443        }
 444}
 445
 446static struct grep_expr *compile_pattern_not(struct grep_pat **list)
 447{
 448        struct grep_pat *p;
 449        struct grep_expr *x;
 450
 451        p = *list;
 452        if (!p)
 453                return NULL;
 454        switch (p->token) {
 455        case GREP_NOT:
 456                if (!p->next)
 457                        die("--not not followed by pattern expression");
 458                *list = p->next;
 459                x = xcalloc(1, sizeof (struct grep_expr));
 460                x->node = GREP_NODE_NOT;
 461                x->u.unary = compile_pattern_not(list);
 462                if (!x->u.unary)
 463                        die("--not followed by non pattern expression");
 464                return x;
 465        default:
 466                return compile_pattern_atom(list);
 467        }
 468}
 469
 470static struct grep_expr *compile_pattern_and(struct grep_pat **list)
 471{
 472        struct grep_pat *p;
 473        struct grep_expr *x, *y, *z;
 474
 475        x = compile_pattern_not(list);
 476        p = *list;
 477        if (p && p->token == GREP_AND) {
 478                if (!p->next)
 479                        die("--and not followed by pattern expression");
 480                *list = p->next;
 481                y = compile_pattern_and(list);
 482                if (!y)
 483                        die("--and not followed by pattern expression");
 484                z = xcalloc(1, sizeof (struct grep_expr));
 485                z->node = GREP_NODE_AND;
 486                z->u.binary.left = x;
 487                z->u.binary.right = y;
 488                return z;
 489        }
 490        return x;
 491}
 492
 493static struct grep_expr *compile_pattern_or(struct grep_pat **list)
 494{
 495        struct grep_pat *p;
 496        struct grep_expr *x, *y, *z;
 497
 498        x = compile_pattern_and(list);
 499        p = *list;
 500        if (x && p && p->token != GREP_CLOSE_PAREN) {
 501                y = compile_pattern_or(list);
 502                if (!y)
 503                        die("not a pattern expression %s", p->pattern);
 504                z = xcalloc(1, sizeof (struct grep_expr));
 505                z->node = GREP_NODE_OR;
 506                z->u.binary.left = x;
 507                z->u.binary.right = y;
 508                return z;
 509        }
 510        return x;
 511}
 512
 513static struct grep_expr *compile_pattern_expr(struct grep_pat **list)
 514{
 515        return compile_pattern_or(list);
 516}
 517
 518static void indent(int in)
 519{
 520        while (in-- > 0)
 521                fputc(' ', stderr);
 522}
 523
 524static void dump_grep_pat(struct grep_pat *p)
 525{
 526        switch (p->token) {
 527        case GREP_AND: fprintf(stderr, "*and*"); break;
 528        case GREP_OPEN_PAREN: fprintf(stderr, "*(*"); break;
 529        case GREP_CLOSE_PAREN: fprintf(stderr, "*)*"); break;
 530        case GREP_NOT: fprintf(stderr, "*not*"); break;
 531        case GREP_OR: fprintf(stderr, "*or*"); break;
 532
 533        case GREP_PATTERN: fprintf(stderr, "pattern"); break;
 534        case GREP_PATTERN_HEAD: fprintf(stderr, "pattern_head"); break;
 535        case GREP_PATTERN_BODY: fprintf(stderr, "pattern_body"); break;
 536        }
 537
 538        switch (p->token) {
 539        default: break;
 540        case GREP_PATTERN_HEAD:
 541                fprintf(stderr, "<head %d>", p->field); break;
 542        case GREP_PATTERN_BODY:
 543                fprintf(stderr, "<body>"); break;
 544        }
 545        switch (p->token) {
 546        default: break;
 547        case GREP_PATTERN_HEAD:
 548        case GREP_PATTERN_BODY:
 549        case GREP_PATTERN:
 550                fprintf(stderr, "%.*s", (int)p->patternlen, p->pattern);
 551                break;
 552        }
 553        fputc('\n', stderr);
 554}
 555
 556static void dump_grep_expression_1(struct grep_expr *x, int in)
 557{
 558        indent(in);
 559        switch (x->node) {
 560        case GREP_NODE_TRUE:
 561                fprintf(stderr, "true\n");
 562                break;
 563        case GREP_NODE_ATOM:
 564                dump_grep_pat(x->u.atom);
 565                break;
 566        case GREP_NODE_NOT:
 567                fprintf(stderr, "(not\n");
 568                dump_grep_expression_1(x->u.unary, in+1);
 569                indent(in);
 570                fprintf(stderr, ")\n");
 571                break;
 572        case GREP_NODE_AND:
 573                fprintf(stderr, "(and\n");
 574                dump_grep_expression_1(x->u.binary.left, in+1);
 575                dump_grep_expression_1(x->u.binary.right, in+1);
 576                indent(in);
 577                fprintf(stderr, ")\n");
 578                break;
 579        case GREP_NODE_OR:
 580                fprintf(stderr, "(or\n");
 581                dump_grep_expression_1(x->u.binary.left, in+1);
 582                dump_grep_expression_1(x->u.binary.right, in+1);
 583                indent(in);
 584                fprintf(stderr, ")\n");
 585                break;
 586        }
 587}
 588
 589static void dump_grep_expression(struct grep_opt *opt)
 590{
 591        struct grep_expr *x = opt->pattern_expression;
 592
 593        if (opt->all_match)
 594                fprintf(stderr, "[all-match]\n");
 595        dump_grep_expression_1(x, 0);
 596        fflush(NULL);
 597}
 598
 599static struct grep_expr *grep_true_expr(void)
 600{
 601        struct grep_expr *z = xcalloc(1, sizeof(*z));
 602        z->node = GREP_NODE_TRUE;
 603        return z;
 604}
 605
 606static struct grep_expr *grep_or_expr(struct grep_expr *left, struct grep_expr *right)
 607{
 608        struct grep_expr *z = xcalloc(1, sizeof(*z));
 609        z->node = GREP_NODE_OR;
 610        z->u.binary.left = left;
 611        z->u.binary.right = right;
 612        return z;
 613}
 614
 615static struct grep_expr *prep_header_patterns(struct grep_opt *opt)
 616{
 617        struct grep_pat *p;
 618        struct grep_expr *header_expr;
 619        struct grep_expr *(header_group[GREP_HEADER_FIELD_MAX]);
 620        enum grep_header_field fld;
 621
 622        if (!opt->header_list)
 623                return NULL;
 624
 625        for (p = opt->header_list; p; p = p->next) {
 626                if (p->token != GREP_PATTERN_HEAD)
 627                        die("bug: a non-header pattern in grep header list.");
 628                if (p->field < GREP_HEADER_FIELD_MIN ||
 629                    GREP_HEADER_FIELD_MAX <= p->field)
 630                        die("bug: unknown header field %d", p->field);
 631                compile_regexp(p, opt);
 632        }
 633
 634        for (fld = 0; fld < GREP_HEADER_FIELD_MAX; fld++)
 635                header_group[fld] = NULL;
 636
 637        for (p = opt->header_list; p; p = p->next) {
 638                struct grep_expr *h;
 639                struct grep_pat *pp = p;
 640
 641                h = compile_pattern_atom(&pp);
 642                if (!h || pp != p->next)
 643                        die("bug: malformed header expr");
 644                if (!header_group[p->field]) {
 645                        header_group[p->field] = h;
 646                        continue;
 647                }
 648                header_group[p->field] = grep_or_expr(h, header_group[p->field]);
 649        }
 650
 651        header_expr = NULL;
 652
 653        for (fld = 0; fld < GREP_HEADER_FIELD_MAX; fld++) {
 654                if (!header_group[fld])
 655                        continue;
 656                if (!header_expr)
 657                        header_expr = grep_true_expr();
 658                header_expr = grep_or_expr(header_group[fld], header_expr);
 659        }
 660        return header_expr;
 661}
 662
 663static struct grep_expr *grep_splice_or(struct grep_expr *x, struct grep_expr *y)
 664{
 665        struct grep_expr *z = x;
 666
 667        while (x) {
 668                assert(x->node == GREP_NODE_OR);
 669                if (x->u.binary.right &&
 670                    x->u.binary.right->node == GREP_NODE_TRUE) {
 671                        x->u.binary.right = y;
 672                        break;
 673                }
 674                x = x->u.binary.right;
 675        }
 676        return z;
 677}
 678
 679static void compile_grep_patterns_real(struct grep_opt *opt)
 680{
 681        struct grep_pat *p;
 682        struct grep_expr *header_expr = prep_header_patterns(opt);
 683
 684        for (p = opt->pattern_list; p; p = p->next) {
 685                switch (p->token) {
 686                case GREP_PATTERN: /* atom */
 687                case GREP_PATTERN_HEAD:
 688                case GREP_PATTERN_BODY:
 689                        compile_regexp(p, opt);
 690                        break;
 691                default:
 692                        opt->extended = 1;
 693                        break;
 694                }
 695        }
 696
 697        if (opt->all_match || header_expr)
 698                opt->extended = 1;
 699        else if (!opt->extended && !opt->debug)
 700                return;
 701
 702        p = opt->pattern_list;
 703        if (p)
 704                opt->pattern_expression = compile_pattern_expr(&p);
 705        if (p)
 706                die("incomplete pattern expression: %s", p->pattern);
 707
 708        if (!header_expr)
 709                return;
 710
 711        if (!opt->pattern_expression)
 712                opt->pattern_expression = header_expr;
 713        else if (opt->all_match)
 714                opt->pattern_expression = grep_splice_or(header_expr,
 715                                                         opt->pattern_expression);
 716        else
 717                opt->pattern_expression = grep_or_expr(opt->pattern_expression,
 718                                                       header_expr);
 719        opt->all_match = 1;
 720}
 721
 722void compile_grep_patterns(struct grep_opt *opt)
 723{
 724        compile_grep_patterns_real(opt);
 725        if (opt->debug)
 726                dump_grep_expression(opt);
 727}
 728
 729static void free_pattern_expr(struct grep_expr *x)
 730{
 731        switch (x->node) {
 732        case GREP_NODE_TRUE:
 733        case GREP_NODE_ATOM:
 734                break;
 735        case GREP_NODE_NOT:
 736                free_pattern_expr(x->u.unary);
 737                break;
 738        case GREP_NODE_AND:
 739        case GREP_NODE_OR:
 740                free_pattern_expr(x->u.binary.left);
 741                free_pattern_expr(x->u.binary.right);
 742                break;
 743        }
 744        free(x);
 745}
 746
 747void free_grep_patterns(struct grep_opt *opt)
 748{
 749        struct grep_pat *p, *n;
 750
 751        for (p = opt->pattern_list; p; p = n) {
 752                n = p->next;
 753                switch (p->token) {
 754                case GREP_PATTERN: /* atom */
 755                case GREP_PATTERN_HEAD:
 756                case GREP_PATTERN_BODY:
 757                        if (p->kws)
 758                                kwsfree(p->kws);
 759                        else if (p->pcre_regexp)
 760                                free_pcre_regexp(p);
 761                        else
 762                                regfree(&p->regexp);
 763                        free(p->pattern);
 764                        break;
 765                default:
 766                        break;
 767                }
 768                free(p);
 769        }
 770
 771        if (!opt->extended)
 772                return;
 773        free_pattern_expr(opt->pattern_expression);
 774}
 775
 776static char *end_of_line(char *cp, unsigned long *left)
 777{
 778        unsigned long l = *left;
 779        while (l && *cp != '\n') {
 780                l--;
 781                cp++;
 782        }
 783        *left = l;
 784        return cp;
 785}
 786
 787static int word_char(char ch)
 788{
 789        return isalnum(ch) || ch == '_';
 790}
 791
 792static void output_color(struct grep_opt *opt, const void *data, size_t size,
 793                         const char *color)
 794{
 795        if (want_color(opt->color) && color && color[0]) {
 796                opt->output(opt, color, strlen(color));
 797                opt->output(opt, data, size);
 798                opt->output(opt, GIT_COLOR_RESET, strlen(GIT_COLOR_RESET));
 799        } else
 800                opt->output(opt, data, size);
 801}
 802
 803static void output_sep(struct grep_opt *opt, char sign)
 804{
 805        if (opt->null_following_name)
 806                opt->output(opt, "\0", 1);
 807        else
 808                output_color(opt, &sign, 1, opt->color_sep);
 809}
 810
 811static void show_name(struct grep_opt *opt, const char *name)
 812{
 813        output_color(opt, name, strlen(name), opt->color_filename);
 814        opt->output(opt, opt->null_following_name ? "\0" : "\n", 1);
 815}
 816
 817static int fixmatch(struct grep_pat *p, char *line, char *eol,
 818                    regmatch_t *match)
 819{
 820        struct kwsmatch kwsm;
 821        size_t offset = kwsexec(p->kws, line, eol - line, &kwsm);
 822        if (offset == -1) {
 823                match->rm_so = match->rm_eo = -1;
 824                return REG_NOMATCH;
 825        } else {
 826                match->rm_so = offset;
 827                match->rm_eo = match->rm_so + kwsm.size[0];
 828                return 0;
 829        }
 830}
 831
 832static int regmatch(const regex_t *preg, char *line, char *eol,
 833                    regmatch_t *match, int eflags)
 834{
 835#ifdef REG_STARTEND
 836        match->rm_so = 0;
 837        match->rm_eo = eol - line;
 838        eflags |= REG_STARTEND;
 839#endif
 840        return regexec(preg, line, 1, match, eflags);
 841}
 842
 843static int patmatch(struct grep_pat *p, char *line, char *eol,
 844                    regmatch_t *match, int eflags)
 845{
 846        int hit;
 847
 848        if (p->fixed)
 849                hit = !fixmatch(p, line, eol, match);
 850        else if (p->pcre_regexp)
 851                hit = !pcrematch(p, line, eol, match, eflags);
 852        else
 853                hit = !regmatch(&p->regexp, line, eol, match, eflags);
 854
 855        return hit;
 856}
 857
 858static int strip_timestamp(char *bol, char **eol_p)
 859{
 860        char *eol = *eol_p;
 861        int ch;
 862
 863        while (bol < --eol) {
 864                if (*eol != '>')
 865                        continue;
 866                *eol_p = ++eol;
 867                ch = *eol;
 868                *eol = '\0';
 869                return ch;
 870        }
 871        return 0;
 872}
 873
 874static struct {
 875        const char *field;
 876        size_t len;
 877} header_field[] = {
 878        { "author ", 7 },
 879        { "committer ", 10 },
 880        { "reflog ", 7 },
 881};
 882
 883static int match_one_pattern(struct grep_pat *p, char *bol, char *eol,
 884                             enum grep_context ctx,
 885                             regmatch_t *pmatch, int eflags)
 886{
 887        int hit = 0;
 888        int saved_ch = 0;
 889        const char *start = bol;
 890
 891        if ((p->token != GREP_PATTERN) &&
 892            ((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD)))
 893                return 0;
 894
 895        if (p->token == GREP_PATTERN_HEAD) {
 896                const char *field;
 897                size_t len;
 898                assert(p->field < ARRAY_SIZE(header_field));
 899                field = header_field[p->field].field;
 900                len = header_field[p->field].len;
 901                if (strncmp(bol, field, len))
 902                        return 0;
 903                bol += len;
 904                switch (p->field) {
 905                case GREP_HEADER_AUTHOR:
 906                case GREP_HEADER_COMMITTER:
 907                        saved_ch = strip_timestamp(bol, &eol);
 908                        break;
 909                default:
 910                        break;
 911                }
 912        }
 913
 914 again:
 915        hit = patmatch(p, bol, eol, pmatch, eflags);
 916
 917        if (hit && p->word_regexp) {
 918                if ((pmatch[0].rm_so < 0) ||
 919                    (eol - bol) < pmatch[0].rm_so ||
 920                    (pmatch[0].rm_eo < 0) ||
 921                    (eol - bol) < pmatch[0].rm_eo)
 922                        die("regexp returned nonsense");
 923
 924                /* Match beginning must be either beginning of the
 925                 * line, or at word boundary (i.e. the last char must
 926                 * not be a word char).  Similarly, match end must be
 927                 * either end of the line, or at word boundary
 928                 * (i.e. the next char must not be a word char).
 929                 */
 930                if ( ((pmatch[0].rm_so == 0) ||
 931                      !word_char(bol[pmatch[0].rm_so-1])) &&
 932                     ((pmatch[0].rm_eo == (eol-bol)) ||
 933                      !word_char(bol[pmatch[0].rm_eo])) )
 934                        ;
 935                else
 936                        hit = 0;
 937
 938                /* Words consist of at least one character. */
 939                if (pmatch->rm_so == pmatch->rm_eo)
 940                        hit = 0;
 941
 942                if (!hit && pmatch[0].rm_so + bol + 1 < eol) {
 943                        /* There could be more than one match on the
 944                         * line, and the first match might not be
 945                         * strict word match.  But later ones could be!
 946                         * Forward to the next possible start, i.e. the
 947                         * next position following a non-word char.
 948                         */
 949                        bol = pmatch[0].rm_so + bol + 1;
 950                        while (word_char(bol[-1]) && bol < eol)
 951                                bol++;
 952                        eflags |= REG_NOTBOL;
 953                        if (bol < eol)
 954                                goto again;
 955                }
 956        }
 957        if (p->token == GREP_PATTERN_HEAD && saved_ch)
 958                *eol = saved_ch;
 959        if (hit) {
 960                pmatch[0].rm_so += bol - start;
 961                pmatch[0].rm_eo += bol - start;
 962        }
 963        return hit;
 964}
 965
 966static int match_expr_eval(struct grep_expr *x, char *bol, char *eol,
 967                           enum grep_context ctx, int collect_hits)
 968{
 969        int h = 0;
 970        regmatch_t match;
 971
 972        if (!x)
 973                die("Not a valid grep expression");
 974        switch (x->node) {
 975        case GREP_NODE_TRUE:
 976                h = 1;
 977                break;
 978        case GREP_NODE_ATOM:
 979                h = match_one_pattern(x->u.atom, bol, eol, ctx, &match, 0);
 980                break;
 981        case GREP_NODE_NOT:
 982                h = !match_expr_eval(x->u.unary, bol, eol, ctx, 0);
 983                break;
 984        case GREP_NODE_AND:
 985                if (!match_expr_eval(x->u.binary.left, bol, eol, ctx, 0))
 986                        return 0;
 987                h = match_expr_eval(x->u.binary.right, bol, eol, ctx, 0);
 988                break;
 989        case GREP_NODE_OR:
 990                if (!collect_hits)
 991                        return (match_expr_eval(x->u.binary.left,
 992                                                bol, eol, ctx, 0) ||
 993                                match_expr_eval(x->u.binary.right,
 994                                                bol, eol, ctx, 0));
 995                h = match_expr_eval(x->u.binary.left, bol, eol, ctx, 0);
 996                x->u.binary.left->hit |= h;
 997                h |= match_expr_eval(x->u.binary.right, bol, eol, ctx, 1);
 998                break;
 999        default:
1000                die("Unexpected node type (internal error) %d", x->node);
1001        }
1002        if (collect_hits)
1003                x->hit |= h;
1004        return h;
1005}
1006
1007static int match_expr(struct grep_opt *opt, char *bol, char *eol,
1008                      enum grep_context ctx, int collect_hits)
1009{
1010        struct grep_expr *x = opt->pattern_expression;
1011        return match_expr_eval(x, bol, eol, ctx, collect_hits);
1012}
1013
1014static int match_line(struct grep_opt *opt, char *bol, char *eol,
1015                      enum grep_context ctx, int collect_hits)
1016{
1017        struct grep_pat *p;
1018        regmatch_t match;
1019
1020        if (opt->extended)
1021                return match_expr(opt, bol, eol, ctx, collect_hits);
1022
1023        /* we do not call with collect_hits without being extended */
1024        for (p = opt->pattern_list; p; p = p->next) {
1025                if (match_one_pattern(p, bol, eol, ctx, &match, 0))
1026                        return 1;
1027        }
1028        return 0;
1029}
1030
1031static int match_next_pattern(struct grep_pat *p, char *bol, char *eol,
1032                              enum grep_context ctx,
1033                              regmatch_t *pmatch, int eflags)
1034{
1035        regmatch_t match;
1036
1037        if (!match_one_pattern(p, bol, eol, ctx, &match, eflags))
1038                return 0;
1039        if (match.rm_so < 0 || match.rm_eo < 0)
1040                return 0;
1041        if (pmatch->rm_so >= 0 && pmatch->rm_eo >= 0) {
1042                if (match.rm_so > pmatch->rm_so)
1043                        return 1;
1044                if (match.rm_so == pmatch->rm_so && match.rm_eo < pmatch->rm_eo)
1045                        return 1;
1046        }
1047        pmatch->rm_so = match.rm_so;
1048        pmatch->rm_eo = match.rm_eo;
1049        return 1;
1050}
1051
1052static int next_match(struct grep_opt *opt, char *bol, char *eol,
1053                      enum grep_context ctx, regmatch_t *pmatch, int eflags)
1054{
1055        struct grep_pat *p;
1056        int hit = 0;
1057
1058        pmatch->rm_so = pmatch->rm_eo = -1;
1059        if (bol < eol) {
1060                for (p = opt->pattern_list; p; p = p->next) {
1061                        switch (p->token) {
1062                        case GREP_PATTERN: /* atom */
1063                        case GREP_PATTERN_HEAD:
1064                        case GREP_PATTERN_BODY:
1065                                hit |= match_next_pattern(p, bol, eol, ctx,
1066                                                          pmatch, eflags);
1067                                break;
1068                        default:
1069                                break;
1070                        }
1071                }
1072        }
1073        return hit;
1074}
1075
1076static void show_line(struct grep_opt *opt, char *bol, char *eol,
1077                      const char *name, unsigned lno, char sign)
1078{
1079        int rest = eol - bol;
1080        char *line_color = NULL;
1081
1082        if (opt->file_break && opt->last_shown == 0) {
1083                if (opt->show_hunk_mark)
1084                        opt->output(opt, "\n", 1);
1085        } else if (opt->pre_context || opt->post_context || opt->funcbody) {
1086                if (opt->last_shown == 0) {
1087                        if (opt->show_hunk_mark) {
1088                                output_color(opt, "--", 2, opt->color_sep);
1089                                opt->output(opt, "\n", 1);
1090                        }
1091                } else if (lno > opt->last_shown + 1) {
1092                        output_color(opt, "--", 2, opt->color_sep);
1093                        opt->output(opt, "\n", 1);
1094                }
1095        }
1096        if (opt->heading && opt->last_shown == 0) {
1097                output_color(opt, name, strlen(name), opt->color_filename);
1098                opt->output(opt, "\n", 1);
1099        }
1100        opt->last_shown = lno;
1101
1102        if (!opt->heading && opt->pathname) {
1103                output_color(opt, name, strlen(name), opt->color_filename);
1104                output_sep(opt, sign);
1105        }
1106        if (opt->linenum) {
1107                char buf[32];
1108                snprintf(buf, sizeof(buf), "%d", lno);
1109                output_color(opt, buf, strlen(buf), opt->color_lineno);
1110                output_sep(opt, sign);
1111        }
1112        if (opt->color) {
1113                regmatch_t match;
1114                enum grep_context ctx = GREP_CONTEXT_BODY;
1115                int ch = *eol;
1116                int eflags = 0;
1117
1118                if (sign == ':')
1119                        line_color = opt->color_selected;
1120                else if (sign == '-')
1121                        line_color = opt->color_context;
1122                else if (sign == '=')
1123                        line_color = opt->color_function;
1124                *eol = '\0';
1125                while (next_match(opt, bol, eol, ctx, &match, eflags)) {
1126                        if (match.rm_so == match.rm_eo)
1127                                break;
1128
1129                        output_color(opt, bol, match.rm_so, line_color);
1130                        output_color(opt, bol + match.rm_so,
1131                                     match.rm_eo - match.rm_so,
1132                                     opt->color_match);
1133                        bol += match.rm_eo;
1134                        rest -= match.rm_eo;
1135                        eflags = REG_NOTBOL;
1136                }
1137                *eol = ch;
1138        }
1139        output_color(opt, bol, rest, line_color);
1140        opt->output(opt, "\n", 1);
1141}
1142
1143#ifndef NO_PTHREADS
1144int grep_use_locks;
1145
1146/*
1147 * This lock protects access to the gitattributes machinery, which is
1148 * not thread-safe.
1149 */
1150pthread_mutex_t grep_attr_mutex;
1151
1152static inline void grep_attr_lock(void)
1153{
1154        if (grep_use_locks)
1155                pthread_mutex_lock(&grep_attr_mutex);
1156}
1157
1158static inline void grep_attr_unlock(void)
1159{
1160        if (grep_use_locks)
1161                pthread_mutex_unlock(&grep_attr_mutex);
1162}
1163
1164/*
1165 * Same as git_attr_mutex, but protecting the thread-unsafe object db access.
1166 */
1167pthread_mutex_t grep_read_mutex;
1168
1169#else
1170#define grep_attr_lock()
1171#define grep_attr_unlock()
1172#endif
1173
1174static int match_funcname(struct grep_opt *opt, struct grep_source *gs, char *bol, char *eol)
1175{
1176        xdemitconf_t *xecfg = opt->priv;
1177        if (xecfg && !xecfg->find_func) {
1178                grep_source_load_driver(gs);
1179                if (gs->driver->funcname.pattern) {
1180                        const struct userdiff_funcname *pe = &gs->driver->funcname;
1181                        xdiff_set_find_func(xecfg, pe->pattern, pe->cflags);
1182                } else {
1183                        xecfg = opt->priv = NULL;
1184                }
1185        }
1186
1187        if (xecfg) {
1188                char buf[1];
1189                return xecfg->find_func(bol, eol - bol, buf, 1,
1190                                        xecfg->find_func_priv) >= 0;
1191        }
1192
1193        if (bol == eol)
1194                return 0;
1195        if (isalpha(*bol) || *bol == '_' || *bol == '$')
1196                return 1;
1197        return 0;
1198}
1199
1200static void show_funcname_line(struct grep_opt *opt, struct grep_source *gs,
1201                               char *bol, unsigned lno)
1202{
1203        while (bol > gs->buf) {
1204                char *eol = --bol;
1205
1206                while (bol > gs->buf && bol[-1] != '\n')
1207                        bol--;
1208                lno--;
1209
1210                if (lno <= opt->last_shown)
1211                        break;
1212
1213                if (match_funcname(opt, gs, bol, eol)) {
1214                        show_line(opt, bol, eol, gs->name, lno, '=');
1215                        break;
1216                }
1217        }
1218}
1219
1220static void show_pre_context(struct grep_opt *opt, struct grep_source *gs,
1221                             char *bol, char *end, unsigned lno)
1222{
1223        unsigned cur = lno, from = 1, funcname_lno = 0;
1224        int funcname_needed = !!opt->funcname;
1225
1226        if (opt->funcbody && !match_funcname(opt, gs, bol, end))
1227                funcname_needed = 2;
1228
1229        if (opt->pre_context < lno)
1230                from = lno - opt->pre_context;
1231        if (from <= opt->last_shown)
1232                from = opt->last_shown + 1;
1233
1234        /* Rewind. */
1235        while (bol > gs->buf &&
1236               cur > (funcname_needed == 2 ? opt->last_shown + 1 : from)) {
1237                char *eol = --bol;
1238
1239                while (bol > gs->buf && bol[-1] != '\n')
1240                        bol--;
1241                cur--;
1242                if (funcname_needed && match_funcname(opt, gs, bol, eol)) {
1243                        funcname_lno = cur;
1244                        funcname_needed = 0;
1245                }
1246        }
1247
1248        /* We need to look even further back to find a function signature. */
1249        if (opt->funcname && funcname_needed)
1250                show_funcname_line(opt, gs, bol, cur);
1251
1252        /* Back forward. */
1253        while (cur < lno) {
1254                char *eol = bol, sign = (cur == funcname_lno) ? '=' : '-';
1255
1256                while (*eol != '\n')
1257                        eol++;
1258                show_line(opt, bol, eol, gs->name, cur, sign);
1259                bol = eol + 1;
1260                cur++;
1261        }
1262}
1263
1264static int should_lookahead(struct grep_opt *opt)
1265{
1266        struct grep_pat *p;
1267
1268        if (opt->extended)
1269                return 0; /* punt for too complex stuff */
1270        if (opt->invert)
1271                return 0;
1272        for (p = opt->pattern_list; p; p = p->next) {
1273                if (p->token != GREP_PATTERN)
1274                        return 0; /* punt for "header only" and stuff */
1275        }
1276        return 1;
1277}
1278
1279static int look_ahead(struct grep_opt *opt,
1280                      unsigned long *left_p,
1281                      unsigned *lno_p,
1282                      char **bol_p)
1283{
1284        unsigned lno = *lno_p;
1285        char *bol = *bol_p;
1286        struct grep_pat *p;
1287        char *sp, *last_bol;
1288        regoff_t earliest = -1;
1289
1290        for (p = opt->pattern_list; p; p = p->next) {
1291                int hit;
1292                regmatch_t m;
1293
1294                hit = patmatch(p, bol, bol + *left_p, &m, 0);
1295                if (!hit || m.rm_so < 0 || m.rm_eo < 0)
1296                        continue;
1297                if (earliest < 0 || m.rm_so < earliest)
1298                        earliest = m.rm_so;
1299        }
1300
1301        if (earliest < 0) {
1302                *bol_p = bol + *left_p;
1303                *left_p = 0;
1304                return 1;
1305        }
1306        for (sp = bol + earliest; bol < sp && sp[-1] != '\n'; sp--)
1307                ; /* find the beginning of the line */
1308        last_bol = sp;
1309
1310        for (sp = bol; sp < last_bol; sp++) {
1311                if (*sp == '\n')
1312                        lno++;
1313        }
1314        *left_p -= last_bol - bol;
1315        *bol_p = last_bol;
1316        *lno_p = lno;
1317        return 0;
1318}
1319
1320static void std_output(struct grep_opt *opt, const void *buf, size_t size)
1321{
1322        fwrite(buf, size, 1, stdout);
1323}
1324
1325static int grep_source_1(struct grep_opt *opt, struct grep_source *gs, int collect_hits)
1326{
1327        char *bol;
1328        unsigned long left;
1329        unsigned lno = 1;
1330        unsigned last_hit = 0;
1331        int binary_match_only = 0;
1332        unsigned count = 0;
1333        int try_lookahead = 0;
1334        int show_function = 0;
1335        enum grep_context ctx = GREP_CONTEXT_HEAD;
1336        xdemitconf_t xecfg;
1337
1338        if (!opt->output)
1339                opt->output = std_output;
1340
1341        if (opt->pre_context || opt->post_context || opt->file_break ||
1342            opt->funcbody) {
1343                /* Show hunk marks, except for the first file. */
1344                if (opt->last_shown)
1345                        opt->show_hunk_mark = 1;
1346                /*
1347                 * If we're using threads then we can't easily identify
1348                 * the first file.  Always put hunk marks in that case
1349                 * and skip the very first one later in work_done().
1350                 */
1351                if (opt->output != std_output)
1352                        opt->show_hunk_mark = 1;
1353        }
1354        opt->last_shown = 0;
1355
1356        switch (opt->binary) {
1357        case GREP_BINARY_DEFAULT:
1358                if (grep_source_is_binary(gs))
1359                        binary_match_only = 1;
1360                break;
1361        case GREP_BINARY_NOMATCH:
1362                if (grep_source_is_binary(gs))
1363                        return 0; /* Assume unmatch */
1364                break;
1365        case GREP_BINARY_TEXT:
1366                break;
1367        default:
1368                die("bug: unknown binary handling mode");
1369        }
1370
1371        memset(&xecfg, 0, sizeof(xecfg));
1372        opt->priv = &xecfg;
1373
1374        try_lookahead = should_lookahead(opt);
1375
1376        if (grep_source_load(gs) < 0)
1377                return 0;
1378
1379        bol = gs->buf;
1380        left = gs->size;
1381        while (left) {
1382                char *eol, ch;
1383                int hit;
1384
1385                /*
1386                 * look_ahead() skips quickly to the line that possibly
1387                 * has the next hit; don't call it if we need to do
1388                 * something more than just skipping the current line
1389                 * in response to an unmatch for the current line.  E.g.
1390                 * inside a post-context window, we will show the current
1391                 * line as a context around the previous hit when it
1392                 * doesn't hit.
1393                 */
1394                if (try_lookahead
1395                    && !(last_hit
1396                         && (show_function ||
1397                             lno <= last_hit + opt->post_context))
1398                    && look_ahead(opt, &left, &lno, &bol))
1399                        break;
1400                eol = end_of_line(bol, &left);
1401                ch = *eol;
1402                *eol = 0;
1403
1404                if ((ctx == GREP_CONTEXT_HEAD) && (eol == bol))
1405                        ctx = GREP_CONTEXT_BODY;
1406
1407                hit = match_line(opt, bol, eol, ctx, collect_hits);
1408                *eol = ch;
1409
1410                if (collect_hits)
1411                        goto next_line;
1412
1413                /* "grep -v -e foo -e bla" should list lines
1414                 * that do not have either, so inversion should
1415                 * be done outside.
1416                 */
1417                if (opt->invert)
1418                        hit = !hit;
1419                if (opt->unmatch_name_only) {
1420                        if (hit)
1421                                return 0;
1422                        goto next_line;
1423                }
1424                if (hit) {
1425                        count++;
1426                        if (opt->status_only)
1427                                return 1;
1428                        if (opt->name_only) {
1429                                show_name(opt, gs->name);
1430                                return 1;
1431                        }
1432                        if (opt->count)
1433                                goto next_line;
1434                        if (binary_match_only) {
1435                                opt->output(opt, "Binary file ", 12);
1436                                output_color(opt, gs->name, strlen(gs->name),
1437                                             opt->color_filename);
1438                                opt->output(opt, " matches\n", 9);
1439                                return 1;
1440                        }
1441                        /* Hit at this line.  If we haven't shown the
1442                         * pre-context lines, we would need to show them.
1443                         */
1444                        if (opt->pre_context || opt->funcbody)
1445                                show_pre_context(opt, gs, bol, eol, lno);
1446                        else if (opt->funcname)
1447                                show_funcname_line(opt, gs, bol, lno);
1448                        show_line(opt, bol, eol, gs->name, lno, ':');
1449                        last_hit = lno;
1450                        if (opt->funcbody)
1451                                show_function = 1;
1452                        goto next_line;
1453                }
1454                if (show_function && match_funcname(opt, gs, bol, eol))
1455                        show_function = 0;
1456                if (show_function ||
1457                    (last_hit && lno <= last_hit + opt->post_context)) {
1458                        /* If the last hit is within the post context,
1459                         * we need to show this line.
1460                         */
1461                        show_line(opt, bol, eol, gs->name, lno, '-');
1462                }
1463
1464        next_line:
1465                bol = eol + 1;
1466                if (!left)
1467                        break;
1468                left--;
1469                lno++;
1470        }
1471
1472        if (collect_hits)
1473                return 0;
1474
1475        if (opt->status_only)
1476                return 0;
1477        if (opt->unmatch_name_only) {
1478                /* We did not see any hit, so we want to show this */
1479                show_name(opt, gs->name);
1480                return 1;
1481        }
1482
1483        xdiff_clear_find_func(&xecfg);
1484        opt->priv = NULL;
1485
1486        /* NEEDSWORK:
1487         * The real "grep -c foo *.c" gives many "bar.c:0" lines,
1488         * which feels mostly useless but sometimes useful.  Maybe
1489         * make it another option?  For now suppress them.
1490         */
1491        if (opt->count && count) {
1492                char buf[32];
1493                output_color(opt, gs->name, strlen(gs->name), opt->color_filename);
1494                output_sep(opt, ':');
1495                snprintf(buf, sizeof(buf), "%u\n", count);
1496                opt->output(opt, buf, strlen(buf));
1497                return 1;
1498        }
1499        return !!last_hit;
1500}
1501
1502static void clr_hit_marker(struct grep_expr *x)
1503{
1504        /* All-hit markers are meaningful only at the very top level
1505         * OR node.
1506         */
1507        while (1) {
1508                x->hit = 0;
1509                if (x->node != GREP_NODE_OR)
1510                        return;
1511                x->u.binary.left->hit = 0;
1512                x = x->u.binary.right;
1513        }
1514}
1515
1516static int chk_hit_marker(struct grep_expr *x)
1517{
1518        /* Top level nodes have hit markers.  See if they all are hits */
1519        while (1) {
1520                if (x->node != GREP_NODE_OR)
1521                        return x->hit;
1522                if (!x->u.binary.left->hit)
1523                        return 0;
1524                x = x->u.binary.right;
1525        }
1526}
1527
1528int grep_source(struct grep_opt *opt, struct grep_source *gs)
1529{
1530        /*
1531         * we do not have to do the two-pass grep when we do not check
1532         * buffer-wide "all-match".
1533         */
1534        if (!opt->all_match)
1535                return grep_source_1(opt, gs, 0);
1536
1537        /* Otherwise the toplevel "or" terms hit a bit differently.
1538         * We first clear hit markers from them.
1539         */
1540        clr_hit_marker(opt->pattern_expression);
1541        grep_source_1(opt, gs, 1);
1542
1543        if (!chk_hit_marker(opt->pattern_expression))
1544                return 0;
1545
1546        return grep_source_1(opt, gs, 0);
1547}
1548
1549int grep_buffer(struct grep_opt *opt, char *buf, unsigned long size)
1550{
1551        struct grep_source gs;
1552        int r;
1553
1554        grep_source_init(&gs, GREP_SOURCE_BUF, NULL, NULL, NULL);
1555        gs.buf = buf;
1556        gs.size = size;
1557
1558        r = grep_source(opt, &gs);
1559
1560        grep_source_clear(&gs);
1561        return r;
1562}
1563
1564void grep_source_init(struct grep_source *gs, enum grep_source_type type,
1565                      const char *name, const char *path,
1566                      const void *identifier)
1567{
1568        gs->type = type;
1569        gs->name = name ? xstrdup(name) : NULL;
1570        gs->path = path ? xstrdup(path) : NULL;
1571        gs->buf = NULL;
1572        gs->size = 0;
1573        gs->driver = NULL;
1574
1575        switch (type) {
1576        case GREP_SOURCE_FILE:
1577                gs->identifier = xstrdup(identifier);
1578                break;
1579        case GREP_SOURCE_SHA1:
1580                gs->identifier = xmalloc(20);
1581                memcpy(gs->identifier, identifier, 20);
1582                break;
1583        case GREP_SOURCE_BUF:
1584                gs->identifier = NULL;
1585        }
1586}
1587
1588void grep_source_clear(struct grep_source *gs)
1589{
1590        free(gs->name);
1591        gs->name = NULL;
1592        free(gs->path);
1593        gs->path = NULL;
1594        free(gs->identifier);
1595        gs->identifier = NULL;
1596        grep_source_clear_data(gs);
1597}
1598
1599void grep_source_clear_data(struct grep_source *gs)
1600{
1601        switch (gs->type) {
1602        case GREP_SOURCE_FILE:
1603        case GREP_SOURCE_SHA1:
1604                free(gs->buf);
1605                gs->buf = NULL;
1606                gs->size = 0;
1607                break;
1608        case GREP_SOURCE_BUF:
1609                /* leave user-provided buf intact */
1610                break;
1611        }
1612}
1613
1614static int grep_source_load_sha1(struct grep_source *gs)
1615{
1616        enum object_type type;
1617
1618        grep_read_lock();
1619        gs->buf = read_sha1_file(gs->identifier, &type, &gs->size);
1620        grep_read_unlock();
1621
1622        if (!gs->buf)
1623                return error(_("'%s': unable to read %s"),
1624                             gs->name,
1625                             sha1_to_hex(gs->identifier));
1626        return 0;
1627}
1628
1629static int grep_source_load_file(struct grep_source *gs)
1630{
1631        const char *filename = gs->identifier;
1632        struct stat st;
1633        char *data;
1634        size_t size;
1635        int i;
1636
1637        if (lstat(filename, &st) < 0) {
1638        err_ret:
1639                if (errno != ENOENT)
1640                        error(_("'%s': %s"), filename, strerror(errno));
1641                return -1;
1642        }
1643        if (!S_ISREG(st.st_mode))
1644                return -1;
1645        size = xsize_t(st.st_size);
1646        i = open(filename, O_RDONLY);
1647        if (i < 0)
1648                goto err_ret;
1649        data = xmalloc(size + 1);
1650        if (st.st_size != read_in_full(i, data, size)) {
1651                error(_("'%s': short read %s"), filename, strerror(errno));
1652                close(i);
1653                free(data);
1654                return -1;
1655        }
1656        close(i);
1657        data[size] = 0;
1658
1659        gs->buf = data;
1660        gs->size = size;
1661        return 0;
1662}
1663
1664static int grep_source_load(struct grep_source *gs)
1665{
1666        if (gs->buf)
1667                return 0;
1668
1669        switch (gs->type) {
1670        case GREP_SOURCE_FILE:
1671                return grep_source_load_file(gs);
1672        case GREP_SOURCE_SHA1:
1673                return grep_source_load_sha1(gs);
1674        case GREP_SOURCE_BUF:
1675                return gs->buf ? 0 : -1;
1676        }
1677        die("BUG: invalid grep_source type");
1678}
1679
1680void grep_source_load_driver(struct grep_source *gs)
1681{
1682        if (gs->driver)
1683                return;
1684
1685        grep_attr_lock();
1686        if (gs->path)
1687                gs->driver = userdiff_find_by_path(gs->path);
1688        if (!gs->driver)
1689                gs->driver = userdiff_find_by_name("default");
1690        grep_attr_unlock();
1691}
1692
1693static int grep_source_is_binary(struct grep_source *gs)
1694{
1695        grep_source_load_driver(gs);
1696        if (gs->driver->binary != -1)
1697                return gs->driver->binary;
1698
1699        if (!grep_source_load(gs))
1700                return buffer_is_binary(gs->buf, gs->size);
1701
1702        return 0;
1703}