Andrew's git / gitweb.git / grep.c
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grep.con commit Merge branch 'nd/index-pack-l10n-buf-overflow' (09386ff)
   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 < 0 || GREP_HEADER_FIELD_MAX <= p->field)
 629                        die("bug: unknown header field %d", p->field);
 630                compile_regexp(p, opt);
 631        }
 632
 633        for (fld = 0; fld < GREP_HEADER_FIELD_MAX; fld++)
 634                header_group[fld] = NULL;
 635
 636        for (p = opt->header_list; p; p = p->next) {
 637                struct grep_expr *h;
 638                struct grep_pat *pp = p;
 639
 640                h = compile_pattern_atom(&pp);
 641                if (!h || pp != p->next)
 642                        die("bug: malformed header expr");
 643                if (!header_group[p->field]) {
 644                        header_group[p->field] = h;
 645                        continue;
 646                }
 647                header_group[p->field] = grep_or_expr(h, header_group[p->field]);
 648        }
 649
 650        header_expr = NULL;
 651
 652        for (fld = 0; fld < GREP_HEADER_FIELD_MAX; fld++) {
 653                if (!header_group[fld])
 654                        continue;
 655                if (!header_expr)
 656                        header_expr = grep_true_expr();
 657                header_expr = grep_or_expr(header_group[fld], header_expr);
 658        }
 659        return header_expr;
 660}
 661
 662static struct grep_expr *grep_splice_or(struct grep_expr *x, struct grep_expr *y)
 663{
 664        struct grep_expr *z = x;
 665
 666        while (x) {
 667                assert(x->node == GREP_NODE_OR);
 668                if (x->u.binary.right &&
 669                    x->u.binary.right->node == GREP_NODE_TRUE) {
 670                        x->u.binary.right = y;
 671                        break;
 672                }
 673                x = x->u.binary.right;
 674        }
 675        return z;
 676}
 677
 678static void compile_grep_patterns_real(struct grep_opt *opt)
 679{
 680        struct grep_pat *p;
 681        struct grep_expr *header_expr = prep_header_patterns(opt);
 682
 683        for (p = opt->pattern_list; p; p = p->next) {
 684                switch (p->token) {
 685                case GREP_PATTERN: /* atom */
 686                case GREP_PATTERN_HEAD:
 687                case GREP_PATTERN_BODY:
 688                        compile_regexp(p, opt);
 689                        break;
 690                default:
 691                        opt->extended = 1;
 692                        break;
 693                }
 694        }
 695
 696        if (opt->all_match || header_expr)
 697                opt->extended = 1;
 698        else if (!opt->extended && !opt->debug)
 699                return;
 700
 701        p = opt->pattern_list;
 702        if (p)
 703                opt->pattern_expression = compile_pattern_expr(&p);
 704        if (p)
 705                die("incomplete pattern expression: %s", p->pattern);
 706
 707        if (!header_expr)
 708                return;
 709
 710        if (!opt->pattern_expression)
 711                opt->pattern_expression = header_expr;
 712        else if (opt->all_match)
 713                opt->pattern_expression = grep_splice_or(header_expr,
 714                                                         opt->pattern_expression);
 715        else
 716                opt->pattern_expression = grep_or_expr(opt->pattern_expression,
 717                                                       header_expr);
 718        opt->all_match = 1;
 719}
 720
 721void compile_grep_patterns(struct grep_opt *opt)
 722{
 723        compile_grep_patterns_real(opt);
 724        if (opt->debug)
 725                dump_grep_expression(opt);
 726}
 727
 728static void free_pattern_expr(struct grep_expr *x)
 729{
 730        switch (x->node) {
 731        case GREP_NODE_TRUE:
 732        case GREP_NODE_ATOM:
 733                break;
 734        case GREP_NODE_NOT:
 735                free_pattern_expr(x->u.unary);
 736                break;
 737        case GREP_NODE_AND:
 738        case GREP_NODE_OR:
 739                free_pattern_expr(x->u.binary.left);
 740                free_pattern_expr(x->u.binary.right);
 741                break;
 742        }
 743        free(x);
 744}
 745
 746void free_grep_patterns(struct grep_opt *opt)
 747{
 748        struct grep_pat *p, *n;
 749
 750        for (p = opt->pattern_list; p; p = n) {
 751                n = p->next;
 752                switch (p->token) {
 753                case GREP_PATTERN: /* atom */
 754                case GREP_PATTERN_HEAD:
 755                case GREP_PATTERN_BODY:
 756                        if (p->kws)
 757                                kwsfree(p->kws);
 758                        else if (p->pcre_regexp)
 759                                free_pcre_regexp(p);
 760                        else
 761                                regfree(&p->regexp);
 762                        free(p->pattern);
 763                        break;
 764                default:
 765                        break;
 766                }
 767                free(p);
 768        }
 769
 770        if (!opt->extended)
 771                return;
 772        free_pattern_expr(opt->pattern_expression);
 773}
 774
 775static char *end_of_line(char *cp, unsigned long *left)
 776{
 777        unsigned long l = *left;
 778        while (l && *cp != '\n') {
 779                l--;
 780                cp++;
 781        }
 782        *left = l;
 783        return cp;
 784}
 785
 786static int word_char(char ch)
 787{
 788        return isalnum(ch) || ch == '_';
 789}
 790
 791static void output_color(struct grep_opt *opt, const void *data, size_t size,
 792                         const char *color)
 793{
 794        if (want_color(opt->color) && color && color[0]) {
 795                opt->output(opt, color, strlen(color));
 796                opt->output(opt, data, size);
 797                opt->output(opt, GIT_COLOR_RESET, strlen(GIT_COLOR_RESET));
 798        } else
 799                opt->output(opt, data, size);
 800}
 801
 802static void output_sep(struct grep_opt *opt, char sign)
 803{
 804        if (opt->null_following_name)
 805                opt->output(opt, "\0", 1);
 806        else
 807                output_color(opt, &sign, 1, opt->color_sep);
 808}
 809
 810static void show_name(struct grep_opt *opt, const char *name)
 811{
 812        output_color(opt, name, strlen(name), opt->color_filename);
 813        opt->output(opt, opt->null_following_name ? "\0" : "\n", 1);
 814}
 815
 816static int fixmatch(struct grep_pat *p, char *line, char *eol,
 817                    regmatch_t *match)
 818{
 819        struct kwsmatch kwsm;
 820        size_t offset = kwsexec(p->kws, line, eol - line, &kwsm);
 821        if (offset == -1) {
 822                match->rm_so = match->rm_eo = -1;
 823                return REG_NOMATCH;
 824        } else {
 825                match->rm_so = offset;
 826                match->rm_eo = match->rm_so + kwsm.size[0];
 827                return 0;
 828        }
 829}
 830
 831static int regmatch(const regex_t *preg, char *line, char *eol,
 832                    regmatch_t *match, int eflags)
 833{
 834#ifdef REG_STARTEND
 835        match->rm_so = 0;
 836        match->rm_eo = eol - line;
 837        eflags |= REG_STARTEND;
 838#endif
 839        return regexec(preg, line, 1, match, eflags);
 840}
 841
 842static int patmatch(struct grep_pat *p, char *line, char *eol,
 843                    regmatch_t *match, int eflags)
 844{
 845        int hit;
 846
 847        if (p->fixed)
 848                hit = !fixmatch(p, line, eol, match);
 849        else if (p->pcre_regexp)
 850                hit = !pcrematch(p, line, eol, match, eflags);
 851        else
 852                hit = !regmatch(&p->regexp, line, eol, match, eflags);
 853
 854        return hit;
 855}
 856
 857static int strip_timestamp(char *bol, char **eol_p)
 858{
 859        char *eol = *eol_p;
 860        int ch;
 861
 862        while (bol < --eol) {
 863                if (*eol != '>')
 864                        continue;
 865                *eol_p = ++eol;
 866                ch = *eol;
 867                *eol = '\0';
 868                return ch;
 869        }
 870        return 0;
 871}
 872
 873static struct {
 874        const char *field;
 875        size_t len;
 876} header_field[] = {
 877        { "author ", 7 },
 878        { "committer ", 10 },
 879        { "reflog ", 7 },
 880};
 881
 882static int match_one_pattern(struct grep_pat *p, char *bol, char *eol,
 883                             enum grep_context ctx,
 884                             regmatch_t *pmatch, int eflags)
 885{
 886        int hit = 0;
 887        int saved_ch = 0;
 888        const char *start = bol;
 889
 890        if ((p->token != GREP_PATTERN) &&
 891            ((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD)))
 892                return 0;
 893
 894        if (p->token == GREP_PATTERN_HEAD) {
 895                const char *field;
 896                size_t len;
 897                assert(p->field < ARRAY_SIZE(header_field));
 898                field = header_field[p->field].field;
 899                len = header_field[p->field].len;
 900                if (strncmp(bol, field, len))
 901                        return 0;
 902                bol += len;
 903                switch (p->field) {
 904                case GREP_HEADER_AUTHOR:
 905                case GREP_HEADER_COMMITTER:
 906                        saved_ch = strip_timestamp(bol, &eol);
 907                        break;
 908                default:
 909                        break;
 910                }
 911        }
 912
 913 again:
 914        hit = patmatch(p, bol, eol, pmatch, eflags);
 915
 916        if (hit && p->word_regexp) {
 917                if ((pmatch[0].rm_so < 0) ||
 918                    (eol - bol) < pmatch[0].rm_so ||
 919                    (pmatch[0].rm_eo < 0) ||
 920                    (eol - bol) < pmatch[0].rm_eo)
 921                        die("regexp returned nonsense");
 922
 923                /* Match beginning must be either beginning of the
 924                 * line, or at word boundary (i.e. the last char must
 925                 * not be a word char).  Similarly, match end must be
 926                 * either end of the line, or at word boundary
 927                 * (i.e. the next char must not be a word char).
 928                 */
 929                if ( ((pmatch[0].rm_so == 0) ||
 930                      !word_char(bol[pmatch[0].rm_so-1])) &&
 931                     ((pmatch[0].rm_eo == (eol-bol)) ||
 932                      !word_char(bol[pmatch[0].rm_eo])) )
 933                        ;
 934                else
 935                        hit = 0;
 936
 937                /* Words consist of at least one character. */
 938                if (pmatch->rm_so == pmatch->rm_eo)
 939                        hit = 0;
 940
 941                if (!hit && pmatch[0].rm_so + bol + 1 < eol) {
 942                        /* There could be more than one match on the
 943                         * line, and the first match might not be
 944                         * strict word match.  But later ones could be!
 945                         * Forward to the next possible start, i.e. the
 946                         * next position following a non-word char.
 947                         */
 948                        bol = pmatch[0].rm_so + bol + 1;
 949                        while (word_char(bol[-1]) && bol < eol)
 950                                bol++;
 951                        eflags |= REG_NOTBOL;
 952                        if (bol < eol)
 953                                goto again;
 954                }
 955        }
 956        if (p->token == GREP_PATTERN_HEAD && saved_ch)
 957                *eol = saved_ch;
 958        if (hit) {
 959                pmatch[0].rm_so += bol - start;
 960                pmatch[0].rm_eo += bol - start;
 961        }
 962        return hit;
 963}
 964
 965static int match_expr_eval(struct grep_expr *x, char *bol, char *eol,
 966                           enum grep_context ctx, int collect_hits)
 967{
 968        int h = 0;
 969        regmatch_t match;
 970
 971        if (!x)
 972                die("Not a valid grep expression");
 973        switch (x->node) {
 974        case GREP_NODE_TRUE:
 975                h = 1;
 976                break;
 977        case GREP_NODE_ATOM:
 978                h = match_one_pattern(x->u.atom, bol, eol, ctx, &match, 0);
 979                break;
 980        case GREP_NODE_NOT:
 981                h = !match_expr_eval(x->u.unary, bol, eol, ctx, 0);
 982                break;
 983        case GREP_NODE_AND:
 984                if (!match_expr_eval(x->u.binary.left, bol, eol, ctx, 0))
 985                        return 0;
 986                h = match_expr_eval(x->u.binary.right, bol, eol, ctx, 0);
 987                break;
 988        case GREP_NODE_OR:
 989                if (!collect_hits)
 990                        return (match_expr_eval(x->u.binary.left,
 991                                                bol, eol, ctx, 0) ||
 992                                match_expr_eval(x->u.binary.right,
 993                                                bol, eol, ctx, 0));
 994                h = match_expr_eval(x->u.binary.left, bol, eol, ctx, 0);
 995                x->u.binary.left->hit |= h;
 996                h |= match_expr_eval(x->u.binary.right, bol, eol, ctx, 1);
 997                break;
 998        default:
 999                die("Unexpected node type (internal error) %d", x->node);
1000        }
1001        if (collect_hits)
1002                x->hit |= h;
1003        return h;
1004}
1005
1006static int match_expr(struct grep_opt *opt, char *bol, char *eol,
1007                      enum grep_context ctx, int collect_hits)
1008{
1009        struct grep_expr *x = opt->pattern_expression;
1010        return match_expr_eval(x, bol, eol, ctx, collect_hits);
1011}
1012
1013static int match_line(struct grep_opt *opt, char *bol, char *eol,
1014                      enum grep_context ctx, int collect_hits)
1015{
1016        struct grep_pat *p;
1017        regmatch_t match;
1018
1019        if (opt->extended)
1020                return match_expr(opt, bol, eol, ctx, collect_hits);
1021
1022        /* we do not call with collect_hits without being extended */
1023        for (p = opt->pattern_list; p; p = p->next) {
1024                if (match_one_pattern(p, bol, eol, ctx, &match, 0))
1025                        return 1;
1026        }
1027        return 0;
1028}
1029
1030static int match_next_pattern(struct grep_pat *p, char *bol, char *eol,
1031                              enum grep_context ctx,
1032                              regmatch_t *pmatch, int eflags)
1033{
1034        regmatch_t match;
1035
1036        if (!match_one_pattern(p, bol, eol, ctx, &match, eflags))
1037                return 0;
1038        if (match.rm_so < 0 || match.rm_eo < 0)
1039                return 0;
1040        if (pmatch->rm_so >= 0 && pmatch->rm_eo >= 0) {
1041                if (match.rm_so > pmatch->rm_so)
1042                        return 1;
1043                if (match.rm_so == pmatch->rm_so && match.rm_eo < pmatch->rm_eo)
1044                        return 1;
1045        }
1046        pmatch->rm_so = match.rm_so;
1047        pmatch->rm_eo = match.rm_eo;
1048        return 1;
1049}
1050
1051static int next_match(struct grep_opt *opt, char *bol, char *eol,
1052                      enum grep_context ctx, regmatch_t *pmatch, int eflags)
1053{
1054        struct grep_pat *p;
1055        int hit = 0;
1056
1057        pmatch->rm_so = pmatch->rm_eo = -1;
1058        if (bol < eol) {
1059                for (p = opt->pattern_list; p; p = p->next) {
1060                        switch (p->token) {
1061                        case GREP_PATTERN: /* atom */
1062                        case GREP_PATTERN_HEAD:
1063                        case GREP_PATTERN_BODY:
1064                                hit |= match_next_pattern(p, bol, eol, ctx,
1065                                                          pmatch, eflags);
1066                                break;
1067                        default:
1068                                break;
1069                        }
1070                }
1071        }
1072        return hit;
1073}
1074
1075static void show_line(struct grep_opt *opt, char *bol, char *eol,
1076                      const char *name, unsigned lno, char sign)
1077{
1078        int rest = eol - bol;
1079        char *line_color = NULL;
1080
1081        if (opt->file_break && opt->last_shown == 0) {
1082                if (opt->show_hunk_mark)
1083                        opt->output(opt, "\n", 1);
1084        } else if (opt->pre_context || opt->post_context || opt->funcbody) {
1085                if (opt->last_shown == 0) {
1086                        if (opt->show_hunk_mark) {
1087                                output_color(opt, "--", 2, opt->color_sep);
1088                                opt->output(opt, "\n", 1);
1089                        }
1090                } else if (lno > opt->last_shown + 1) {
1091                        output_color(opt, "--", 2, opt->color_sep);
1092                        opt->output(opt, "\n", 1);
1093                }
1094        }
1095        if (opt->heading && opt->last_shown == 0) {
1096                output_color(opt, name, strlen(name), opt->color_filename);
1097                opt->output(opt, "\n", 1);
1098        }
1099        opt->last_shown = lno;
1100
1101        if (!opt->heading && opt->pathname) {
1102                output_color(opt, name, strlen(name), opt->color_filename);
1103                output_sep(opt, sign);
1104        }
1105        if (opt->linenum) {
1106                char buf[32];
1107                snprintf(buf, sizeof(buf), "%d", lno);
1108                output_color(opt, buf, strlen(buf), opt->color_lineno);
1109                output_sep(opt, sign);
1110        }
1111        if (opt->color) {
1112                regmatch_t match;
1113                enum grep_context ctx = GREP_CONTEXT_BODY;
1114                int ch = *eol;
1115                int eflags = 0;
1116
1117                if (sign == ':')
1118                        line_color = opt->color_selected;
1119                else if (sign == '-')
1120                        line_color = opt->color_context;
1121                else if (sign == '=')
1122                        line_color = opt->color_function;
1123                *eol = '\0';
1124                while (next_match(opt, bol, eol, ctx, &match, eflags)) {
1125                        if (match.rm_so == match.rm_eo)
1126                                break;
1127
1128                        output_color(opt, bol, match.rm_so, line_color);
1129                        output_color(opt, bol + match.rm_so,
1130                                     match.rm_eo - match.rm_so,
1131                                     opt->color_match);
1132                        bol += match.rm_eo;
1133                        rest -= match.rm_eo;
1134                        eflags = REG_NOTBOL;
1135                }
1136                *eol = ch;
1137        }
1138        output_color(opt, bol, rest, line_color);
1139        opt->output(opt, "\n", 1);
1140}
1141
1142#ifndef NO_PTHREADS
1143int grep_use_locks;
1144
1145/*
1146 * This lock protects access to the gitattributes machinery, which is
1147 * not thread-safe.
1148 */
1149pthread_mutex_t grep_attr_mutex;
1150
1151static inline void grep_attr_lock(void)
1152{
1153        if (grep_use_locks)
1154                pthread_mutex_lock(&grep_attr_mutex);
1155}
1156
1157static inline void grep_attr_unlock(void)
1158{
1159        if (grep_use_locks)
1160                pthread_mutex_unlock(&grep_attr_mutex);
1161}
1162
1163/*
1164 * Same as git_attr_mutex, but protecting the thread-unsafe object db access.
1165 */
1166pthread_mutex_t grep_read_mutex;
1167
1168#else
1169#define grep_attr_lock()
1170#define grep_attr_unlock()
1171#endif
1172
1173static int match_funcname(struct grep_opt *opt, struct grep_source *gs, char *bol, char *eol)
1174{
1175        xdemitconf_t *xecfg = opt->priv;
1176        if (xecfg && !xecfg->find_func) {
1177                grep_source_load_driver(gs);
1178                if (gs->driver->funcname.pattern) {
1179                        const struct userdiff_funcname *pe = &gs->driver->funcname;
1180                        xdiff_set_find_func(xecfg, pe->pattern, pe->cflags);
1181                } else {
1182                        xecfg = opt->priv = NULL;
1183                }
1184        }
1185
1186        if (xecfg) {
1187                char buf[1];
1188                return xecfg->find_func(bol, eol - bol, buf, 1,
1189                                        xecfg->find_func_priv) >= 0;
1190        }
1191
1192        if (bol == eol)
1193                return 0;
1194        if (isalpha(*bol) || *bol == '_' || *bol == '$')
1195                return 1;
1196        return 0;
1197}
1198
1199static void show_funcname_line(struct grep_opt *opt, struct grep_source *gs,
1200                               char *bol, unsigned lno)
1201{
1202        while (bol > gs->buf) {
1203                char *eol = --bol;
1204
1205                while (bol > gs->buf && bol[-1] != '\n')
1206                        bol--;
1207                lno--;
1208
1209                if (lno <= opt->last_shown)
1210                        break;
1211
1212                if (match_funcname(opt, gs, bol, eol)) {
1213                        show_line(opt, bol, eol, gs->name, lno, '=');
1214                        break;
1215                }
1216        }
1217}
1218
1219static void show_pre_context(struct grep_opt *opt, struct grep_source *gs,
1220                             char *bol, char *end, unsigned lno)
1221{
1222        unsigned cur = lno, from = 1, funcname_lno = 0;
1223        int funcname_needed = !!opt->funcname;
1224
1225        if (opt->funcbody && !match_funcname(opt, gs, bol, end))
1226                funcname_needed = 2;
1227
1228        if (opt->pre_context < lno)
1229                from = lno - opt->pre_context;
1230        if (from <= opt->last_shown)
1231                from = opt->last_shown + 1;
1232
1233        /* Rewind. */
1234        while (bol > gs->buf &&
1235               cur > (funcname_needed == 2 ? opt->last_shown + 1 : from)) {
1236                char *eol = --bol;
1237
1238                while (bol > gs->buf && bol[-1] != '\n')
1239                        bol--;
1240                cur--;
1241                if (funcname_needed && match_funcname(opt, gs, bol, eol)) {
1242                        funcname_lno = cur;
1243                        funcname_needed = 0;
1244                }
1245        }
1246
1247        /* We need to look even further back to find a function signature. */
1248        if (opt->funcname && funcname_needed)
1249                show_funcname_line(opt, gs, bol, cur);
1250
1251        /* Back forward. */
1252        while (cur < lno) {
1253                char *eol = bol, sign = (cur == funcname_lno) ? '=' : '-';
1254
1255                while (*eol != '\n')
1256                        eol++;
1257                show_line(opt, bol, eol, gs->name, cur, sign);
1258                bol = eol + 1;
1259                cur++;
1260        }
1261}
1262
1263static int should_lookahead(struct grep_opt *opt)
1264{
1265        struct grep_pat *p;
1266
1267        if (opt->extended)
1268                return 0; /* punt for too complex stuff */
1269        if (opt->invert)
1270                return 0;
1271        for (p = opt->pattern_list; p; p = p->next) {
1272                if (p->token != GREP_PATTERN)
1273                        return 0; /* punt for "header only" and stuff */
1274        }
1275        return 1;
1276}
1277
1278static int look_ahead(struct grep_opt *opt,
1279                      unsigned long *left_p,
1280                      unsigned *lno_p,
1281                      char **bol_p)
1282{
1283        unsigned lno = *lno_p;
1284        char *bol = *bol_p;
1285        struct grep_pat *p;
1286        char *sp, *last_bol;
1287        regoff_t earliest = -1;
1288
1289        for (p = opt->pattern_list; p; p = p->next) {
1290                int hit;
1291                regmatch_t m;
1292
1293                hit = patmatch(p, bol, bol + *left_p, &m, 0);
1294                if (!hit || m.rm_so < 0 || m.rm_eo < 0)
1295                        continue;
1296                if (earliest < 0 || m.rm_so < earliest)
1297                        earliest = m.rm_so;
1298        }
1299
1300        if (earliest < 0) {
1301                *bol_p = bol + *left_p;
1302                *left_p = 0;
1303                return 1;
1304        }
1305        for (sp = bol + earliest; bol < sp && sp[-1] != '\n'; sp--)
1306                ; /* find the beginning of the line */
1307        last_bol = sp;
1308
1309        for (sp = bol; sp < last_bol; sp++) {
1310                if (*sp == '\n')
1311                        lno++;
1312        }
1313        *left_p -= last_bol - bol;
1314        *bol_p = last_bol;
1315        *lno_p = lno;
1316        return 0;
1317}
1318
1319static void std_output(struct grep_opt *opt, const void *buf, size_t size)
1320{
1321        fwrite(buf, size, 1, stdout);
1322}
1323
1324static int grep_source_1(struct grep_opt *opt, struct grep_source *gs, int collect_hits)
1325{
1326        char *bol;
1327        unsigned long left;
1328        unsigned lno = 1;
1329        unsigned last_hit = 0;
1330        int binary_match_only = 0;
1331        unsigned count = 0;
1332        int try_lookahead = 0;
1333        int show_function = 0;
1334        enum grep_context ctx = GREP_CONTEXT_HEAD;
1335        xdemitconf_t xecfg;
1336
1337        if (!opt->output)
1338                opt->output = std_output;
1339
1340        if (opt->pre_context || opt->post_context || opt->file_break ||
1341            opt->funcbody) {
1342                /* Show hunk marks, except for the first file. */
1343                if (opt->last_shown)
1344                        opt->show_hunk_mark = 1;
1345                /*
1346                 * If we're using threads then we can't easily identify
1347                 * the first file.  Always put hunk marks in that case
1348                 * and skip the very first one later in work_done().
1349                 */
1350                if (opt->output != std_output)
1351                        opt->show_hunk_mark = 1;
1352        }
1353        opt->last_shown = 0;
1354
1355        switch (opt->binary) {
1356        case GREP_BINARY_DEFAULT:
1357                if (grep_source_is_binary(gs))
1358                        binary_match_only = 1;
1359                break;
1360        case GREP_BINARY_NOMATCH:
1361                if (grep_source_is_binary(gs))
1362                        return 0; /* Assume unmatch */
1363                break;
1364        case GREP_BINARY_TEXT:
1365                break;
1366        default:
1367                die("bug: unknown binary handling mode");
1368        }
1369
1370        memset(&xecfg, 0, sizeof(xecfg));
1371        opt->priv = &xecfg;
1372
1373        try_lookahead = should_lookahead(opt);
1374
1375        if (grep_source_load(gs) < 0)
1376                return 0;
1377
1378        bol = gs->buf;
1379        left = gs->size;
1380        while (left) {
1381                char *eol, ch;
1382                int hit;
1383
1384                /*
1385                 * look_ahead() skips quickly to the line that possibly
1386                 * has the next hit; don't call it if we need to do
1387                 * something more than just skipping the current line
1388                 * in response to an unmatch for the current line.  E.g.
1389                 * inside a post-context window, we will show the current
1390                 * line as a context around the previous hit when it
1391                 * doesn't hit.
1392                 */
1393                if (try_lookahead
1394                    && !(last_hit
1395                         && (show_function ||
1396                             lno <= last_hit + opt->post_context))
1397                    && look_ahead(opt, &left, &lno, &bol))
1398                        break;
1399                eol = end_of_line(bol, &left);
1400                ch = *eol;
1401                *eol = 0;
1402
1403                if ((ctx == GREP_CONTEXT_HEAD) && (eol == bol))
1404                        ctx = GREP_CONTEXT_BODY;
1405
1406                hit = match_line(opt, bol, eol, ctx, collect_hits);
1407                *eol = ch;
1408
1409                if (collect_hits)
1410                        goto next_line;
1411
1412                /* "grep -v -e foo -e bla" should list lines
1413                 * that do not have either, so inversion should
1414                 * be done outside.
1415                 */
1416                if (opt->invert)
1417                        hit = !hit;
1418                if (opt->unmatch_name_only) {
1419                        if (hit)
1420                                return 0;
1421                        goto next_line;
1422                }
1423                if (hit) {
1424                        count++;
1425                        if (opt->status_only)
1426                                return 1;
1427                        if (opt->name_only) {
1428                                show_name(opt, gs->name);
1429                                return 1;
1430                        }
1431                        if (opt->count)
1432                                goto next_line;
1433                        if (binary_match_only) {
1434                                opt->output(opt, "Binary file ", 12);
1435                                output_color(opt, gs->name, strlen(gs->name),
1436                                             opt->color_filename);
1437                                opt->output(opt, " matches\n", 9);
1438                                return 1;
1439                        }
1440                        /* Hit at this line.  If we haven't shown the
1441                         * pre-context lines, we would need to show them.
1442                         */
1443                        if (opt->pre_context || opt->funcbody)
1444                                show_pre_context(opt, gs, bol, eol, lno);
1445                        else if (opt->funcname)
1446                                show_funcname_line(opt, gs, bol, lno);
1447                        show_line(opt, bol, eol, gs->name, lno, ':');
1448                        last_hit = lno;
1449                        if (opt->funcbody)
1450                                show_function = 1;
1451                        goto next_line;
1452                }
1453                if (show_function && match_funcname(opt, gs, bol, eol))
1454                        show_function = 0;
1455                if (show_function ||
1456                    (last_hit && lno <= last_hit + opt->post_context)) {
1457                        /* If the last hit is within the post context,
1458                         * we need to show this line.
1459                         */
1460                        show_line(opt, bol, eol, gs->name, lno, '-');
1461                }
1462
1463        next_line:
1464                bol = eol + 1;
1465                if (!left)
1466                        break;
1467                left--;
1468                lno++;
1469        }
1470
1471        if (collect_hits)
1472                return 0;
1473
1474        if (opt->status_only)
1475                return 0;
1476        if (opt->unmatch_name_only) {
1477                /* We did not see any hit, so we want to show this */
1478                show_name(opt, gs->name);
1479                return 1;
1480        }
1481
1482        xdiff_clear_find_func(&xecfg);
1483        opt->priv = NULL;
1484
1485        /* NEEDSWORK:
1486         * The real "grep -c foo *.c" gives many "bar.c:0" lines,
1487         * which feels mostly useless but sometimes useful.  Maybe
1488         * make it another option?  For now suppress them.
1489         */
1490        if (opt->count && count) {
1491                char buf[32];
1492                output_color(opt, gs->name, strlen(gs->name), opt->color_filename);
1493                output_sep(opt, ':');
1494                snprintf(buf, sizeof(buf), "%u\n", count);
1495                opt->output(opt, buf, strlen(buf));
1496                return 1;
1497        }
1498        return !!last_hit;
1499}
1500
1501static void clr_hit_marker(struct grep_expr *x)
1502{
1503        /* All-hit markers are meaningful only at the very top level
1504         * OR node.
1505         */
1506        while (1) {
1507                x->hit = 0;
1508                if (x->node != GREP_NODE_OR)
1509                        return;
1510                x->u.binary.left->hit = 0;
1511                x = x->u.binary.right;
1512        }
1513}
1514
1515static int chk_hit_marker(struct grep_expr *x)
1516{
1517        /* Top level nodes have hit markers.  See if they all are hits */
1518        while (1) {
1519                if (x->node != GREP_NODE_OR)
1520                        return x->hit;
1521                if (!x->u.binary.left->hit)
1522                        return 0;
1523                x = x->u.binary.right;
1524        }
1525}
1526
1527int grep_source(struct grep_opt *opt, struct grep_source *gs)
1528{
1529        /*
1530         * we do not have to do the two-pass grep when we do not check
1531         * buffer-wide "all-match".
1532         */
1533        if (!opt->all_match)
1534                return grep_source_1(opt, gs, 0);
1535
1536        /* Otherwise the toplevel "or" terms hit a bit differently.
1537         * We first clear hit markers from them.
1538         */
1539        clr_hit_marker(opt->pattern_expression);
1540        grep_source_1(opt, gs, 1);
1541
1542        if (!chk_hit_marker(opt->pattern_expression))
1543                return 0;
1544
1545        return grep_source_1(opt, gs, 0);
1546}
1547
1548int grep_buffer(struct grep_opt *opt, char *buf, unsigned long size)
1549{
1550        struct grep_source gs;
1551        int r;
1552
1553        grep_source_init(&gs, GREP_SOURCE_BUF, NULL, NULL, NULL);
1554        gs.buf = buf;
1555        gs.size = size;
1556
1557        r = grep_source(opt, &gs);
1558
1559        grep_source_clear(&gs);
1560        return r;
1561}
1562
1563void grep_source_init(struct grep_source *gs, enum grep_source_type type,
1564                      const char *name, const char *path,
1565                      const void *identifier)
1566{
1567        gs->type = type;
1568        gs->name = name ? xstrdup(name) : NULL;
1569        gs->path = path ? xstrdup(path) : NULL;
1570        gs->buf = NULL;
1571        gs->size = 0;
1572        gs->driver = NULL;
1573
1574        switch (type) {
1575        case GREP_SOURCE_FILE:
1576                gs->identifier = xstrdup(identifier);
1577                break;
1578        case GREP_SOURCE_SHA1:
1579                gs->identifier = xmalloc(20);
1580                memcpy(gs->identifier, identifier, 20);
1581                break;
1582        case GREP_SOURCE_BUF:
1583                gs->identifier = NULL;
1584        }
1585}
1586
1587void grep_source_clear(struct grep_source *gs)
1588{
1589        free(gs->name);
1590        gs->name = NULL;
1591        free(gs->path);
1592        gs->path = NULL;
1593        free(gs->identifier);
1594        gs->identifier = NULL;
1595        grep_source_clear_data(gs);
1596}
1597
1598void grep_source_clear_data(struct grep_source *gs)
1599{
1600        switch (gs->type) {
1601        case GREP_SOURCE_FILE:
1602        case GREP_SOURCE_SHA1:
1603                free(gs->buf);
1604                gs->buf = NULL;
1605                gs->size = 0;
1606                break;
1607        case GREP_SOURCE_BUF:
1608                /* leave user-provided buf intact */
1609                break;
1610        }
1611}
1612
1613static int grep_source_load_sha1(struct grep_source *gs)
1614{
1615        enum object_type type;
1616
1617        grep_read_lock();
1618        gs->buf = read_sha1_file(gs->identifier, &type, &gs->size);
1619        grep_read_unlock();
1620
1621        if (!gs->buf)
1622                return error(_("'%s': unable to read %s"),
1623                             gs->name,
1624                             sha1_to_hex(gs->identifier));
1625        return 0;
1626}
1627
1628static int grep_source_load_file(struct grep_source *gs)
1629{
1630        const char *filename = gs->identifier;
1631        struct stat st;
1632        char *data;
1633        size_t size;
1634        int i;
1635
1636        if (lstat(filename, &st) < 0) {
1637        err_ret:
1638                if (errno != ENOENT)
1639                        error(_("'%s': %s"), filename, strerror(errno));
1640                return -1;
1641        }
1642        if (!S_ISREG(st.st_mode))
1643                return -1;
1644        size = xsize_t(st.st_size);
1645        i = open(filename, O_RDONLY);
1646        if (i < 0)
1647                goto err_ret;
1648        data = xmalloc(size + 1);
1649        if (st.st_size != read_in_full(i, data, size)) {
1650                error(_("'%s': short read %s"), filename, strerror(errno));
1651                close(i);
1652                free(data);
1653                return -1;
1654        }
1655        close(i);
1656        data[size] = 0;
1657
1658        gs->buf = data;
1659        gs->size = size;
1660        return 0;
1661}
1662
1663static int grep_source_load(struct grep_source *gs)
1664{
1665        if (gs->buf)
1666                return 0;
1667
1668        switch (gs->type) {
1669        case GREP_SOURCE_FILE:
1670                return grep_source_load_file(gs);
1671        case GREP_SOURCE_SHA1:
1672                return grep_source_load_sha1(gs);
1673        case GREP_SOURCE_BUF:
1674                return gs->buf ? 0 : -1;
1675        }
1676        die("BUG: invalid grep_source type");
1677}
1678
1679void grep_source_load_driver(struct grep_source *gs)
1680{
1681        if (gs->driver)
1682                return;
1683
1684        grep_attr_lock();
1685        if (gs->path)
1686                gs->driver = userdiff_find_by_path(gs->path);
1687        if (!gs->driver)
1688                gs->driver = userdiff_find_by_name("default");
1689        grep_attr_unlock();
1690}
1691
1692static int grep_source_is_binary(struct grep_source *gs)
1693{
1694        grep_source_load_driver(gs);
1695        if (gs->driver->binary != -1)
1696                return gs->driver->binary;
1697
1698        if (!grep_source_load(gs))
1699                return buffer_is_binary(gs->buf, gs->size);
1700
1701        return 0;
1702}