Andrew's git - gitweb.git/blob

621e6ec22eb1ddac5c7db3383561aa90486faeba
   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
  20        memset(opt, 0, sizeof(*opt));
  21        opt->relative = 1;
  22        opt->pathname = 1;
  23        opt->regflags = REG_NEWLINE;
  24        opt->max_depth = -1;
  25        opt->pattern_type_option = GREP_PATTERN_TYPE_UNSPECIFIED;
  26        opt->extended_regexp_option = 0;
  27        strcpy(opt->color_context, "");
  28        strcpy(opt->color_filename, "");
  29        strcpy(opt->color_function, "");
  30        strcpy(opt->color_lineno, "");
  31        strcpy(opt->color_match, GIT_COLOR_BOLD_RED);
  32        strcpy(opt->color_selected, "");
  33        strcpy(opt->color_sep, GIT_COLOR_CYAN);
  34        opt->color = -1;
  35}
  36
  37static int parse_pattern_type_arg(const char *opt, const char *arg)
  38{
  39        if (!strcmp(arg, "default"))
  40                return GREP_PATTERN_TYPE_UNSPECIFIED;
  41        else if (!strcmp(arg, "basic"))
  42                return GREP_PATTERN_TYPE_BRE;
  43        else if (!strcmp(arg, "extended"))
  44                return GREP_PATTERN_TYPE_ERE;
  45        else if (!strcmp(arg, "fixed"))
  46                return GREP_PATTERN_TYPE_FIXED;
  47        else if (!strcmp(arg, "perl"))
  48                return GREP_PATTERN_TYPE_PCRE;
  49        die("bad %s argument: %s", opt, arg);
  50}
  51
  52/*
  53 * Read the configuration file once and store it in
  54 * the grep_defaults template.
  55 */
  56int grep_config(const char *var, const char *value, void *cb)
  57{
  58        struct grep_opt *opt = &grep_defaults;
  59        char *color = NULL;
  60
  61        if (userdiff_config(var, value) < 0)
  62                return -1;
  63
  64        if (!strcmp(var, "grep.extendedregexp")) {
  65                if (git_config_bool(var, value))
  66                        opt->extended_regexp_option = 1;
  67                else
  68                        opt->extended_regexp_option = 0;
  69                return 0;
  70        }
  71
  72        if (!strcmp(var, "grep.patterntype")) {
  73                opt->pattern_type_option = parse_pattern_type_arg(var, value);
  74                return 0;
  75        }
  76
  77        if (!strcmp(var, "grep.linenumber")) {
  78                opt->linenum = git_config_bool(var, value);
  79                return 0;
  80        }
  81
  82        if (!strcmp(var, "color.grep"))
  83                opt->color = git_config_colorbool(var, value);
  84        else if (!strcmp(var, "color.grep.context"))
  85                color = opt->color_context;
  86        else if (!strcmp(var, "color.grep.filename"))
  87                color = opt->color_filename;
  88        else if (!strcmp(var, "color.grep.function"))
  89                color = opt->color_function;
  90        else if (!strcmp(var, "color.grep.linenumber"))
  91                color = opt->color_lineno;
  92        else if (!strcmp(var, "color.grep.match"))
  93                color = opt->color_match;
  94        else if (!strcmp(var, "color.grep.selected"))
  95                color = opt->color_selected;
  96        else if (!strcmp(var, "color.grep.separator"))
  97                color = opt->color_sep;
  98
  99        if (color) {
 100                if (!value)
 101                        return config_error_nonbool(var);
 102                color_parse(value, var, color);
 103        }
 104        return 0;
 105}
 106
 107/*
 108 * Initialize one instance of grep_opt and copy the
 109 * default values from the template we read the configuration
 110 * information in an earlier call to git_config(grep_config).
 111 */
 112void grep_init(struct grep_opt *opt, const char *prefix)
 113{
 114        struct grep_opt *def = &grep_defaults;
 115
 116        memset(opt, 0, sizeof(*opt));
 117        opt->prefix = prefix;
 118        opt->prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
 119        opt->pattern_tail = &opt->pattern_list;
 120        opt->header_tail = &opt->header_list;
 121
 122        opt->color = def->color;
 123        opt->extended_regexp_option = def->extended_regexp_option;
 124        opt->pattern_type_option = def->pattern_type_option;
 125        opt->linenum = def->linenum;
 126        opt->max_depth = def->max_depth;
 127        opt->pathname = def->pathname;
 128        opt->regflags = def->regflags;
 129        opt->relative = def->relative;
 130
 131        strcpy(opt->color_context, def->color_context);
 132        strcpy(opt->color_filename, def->color_filename);
 133        strcpy(opt->color_function, def->color_function);
 134        strcpy(opt->color_lineno, def->color_lineno);
 135        strcpy(opt->color_match, def->color_match);
 136        strcpy(opt->color_selected, def->color_selected);
 137        strcpy(opt->color_sep, def->color_sep);
 138}
 139
 140static struct grep_pat *create_grep_pat(const char *pat, size_t patlen,
 141                                        const char *origin, int no,
 142                                        enum grep_pat_token t,
 143                                        enum grep_header_field field)
 144{
 145        struct grep_pat *p = xcalloc(1, sizeof(*p));
 146        p->pattern = xmemdupz(pat, patlen);
 147        p->patternlen = patlen;
 148        p->origin = origin;
 149        p->no = no;
 150        p->token = t;
 151        p->field = field;
 152        return p;
 153}
 154
 155static void do_append_grep_pat(struct grep_pat ***tail, struct grep_pat *p)
 156{
 157        **tail = p;
 158        *tail = &p->next;
 159        p->next = NULL;
 160
 161        switch (p->token) {
 162        case GREP_PATTERN: /* atom */
 163        case GREP_PATTERN_HEAD:
 164        case GREP_PATTERN_BODY:
 165                for (;;) {
 166                        struct grep_pat *new_pat;
 167                        size_t len = 0;
 168                        char *cp = p->pattern + p->patternlen, *nl = NULL;
 169                        while (++len <= p->patternlen) {
 170                                if (*(--cp) == '\n') {
 171                                        nl = cp;
 172                                        break;
 173                                }
 174                        }
 175                        if (!nl)
 176                                break;
 177                        new_pat = create_grep_pat(nl + 1, len - 1, p->origin,
 178                                                  p->no, p->token, p->field);
 179                        new_pat->next = p->next;
 180                        if (!p->next)
 181                                *tail = &new_pat->next;
 182                        p->next = new_pat;
 183                        *nl = '\0';
 184                        p->patternlen -= len;
 185                }
 186                break;
 187        default:
 188                break;
 189        }
 190}
 191
 192void append_header_grep_pattern(struct grep_opt *opt,
 193                                enum grep_header_field field, const char *pat)
 194{
 195        struct grep_pat *p = create_grep_pat(pat, strlen(pat), "header", 0,
 196                                             GREP_PATTERN_HEAD, field);
 197        if (field == GREP_HEADER_REFLOG)
 198                opt->use_reflog_filter = 1;
 199        do_append_grep_pat(&opt->header_tail, p);
 200}
 201
 202void append_grep_pattern(struct grep_opt *opt, const char *pat,
 203                         const char *origin, int no, enum grep_pat_token t)
 204{
 205        append_grep_pat(opt, pat, strlen(pat), origin, no, t);
 206}
 207
 208void append_grep_pat(struct grep_opt *opt, const char *pat, size_t patlen,
 209                     const char *origin, int no, enum grep_pat_token t)
 210{
 211        struct grep_pat *p = create_grep_pat(pat, patlen, origin, no, t, 0);
 212        do_append_grep_pat(&opt->pattern_tail, p);
 213}
 214
 215struct grep_opt *grep_opt_dup(const struct grep_opt *opt)
 216{
 217        struct grep_pat *pat;
 218        struct grep_opt *ret = xmalloc(sizeof(struct grep_opt));
 219        *ret = *opt;
 220
 221        ret->pattern_list = NULL;
 222        ret->pattern_tail = &ret->pattern_list;
 223
 224        for(pat = opt->pattern_list; pat != NULL; pat = pat->next)
 225        {
 226                if(pat->token == GREP_PATTERN_HEAD)
 227                        append_header_grep_pattern(ret, pat->field,
 228                                                   pat->pattern);
 229                else
 230                        append_grep_pat(ret, pat->pattern, pat->patternlen,
 231                                        pat->origin, pat->no, pat->token);
 232        }
 233
 234        return ret;
 235}
 236
 237static NORETURN void compile_regexp_failed(const struct grep_pat *p,
 238                const char *error)
 239{
 240        char where[1024];
 241
 242        if (p->no)
 243                sprintf(where, "In '%s' at %d, ", p->origin, p->no);
 244        else if (p->origin)
 245                sprintf(where, "%s, ", p->origin);
 246        else
 247                where[0] = 0;
 248
 249        die("%s'%s': %s", where, p->pattern, error);
 250}
 251
 252#ifdef USE_LIBPCRE
 253static void compile_pcre_regexp(struct grep_pat *p, const struct grep_opt *opt)
 254{
 255        const char *error;
 256        int erroffset;
 257        int options = PCRE_MULTILINE;
 258
 259        if (opt->ignore_case)
 260                options |= PCRE_CASELESS;
 261
 262        p->pcre_regexp = pcre_compile(p->pattern, options, &error, &erroffset,
 263                        NULL);
 264        if (!p->pcre_regexp)
 265                compile_regexp_failed(p, error);
 266
 267        p->pcre_extra_info = pcre_study(p->pcre_regexp, 0, &error);
 268        if (!p->pcre_extra_info && error)
 269                die("%s", error);
 270}
 271
 272static int pcrematch(struct grep_pat *p, const char *line, const char *eol,
 273                regmatch_t *match, int eflags)
 274{
 275        int ovector[30], ret, flags = 0;
 276
 277        if (eflags & REG_NOTBOL)
 278                flags |= PCRE_NOTBOL;
 279
 280        ret = pcre_exec(p->pcre_regexp, p->pcre_extra_info, line, eol - line,
 281                        0, flags, ovector, ARRAY_SIZE(ovector));
 282        if (ret < 0 && ret != PCRE_ERROR_NOMATCH)
 283                die("pcre_exec failed with error code %d", ret);
 284        if (ret > 0) {
 285                ret = 0;
 286                match->rm_so = ovector[0];
 287                match->rm_eo = ovector[1];
 288        }
 289
 290        return ret;
 291}
 292
 293static void free_pcre_regexp(struct grep_pat *p)
 294{
 295        pcre_free(p->pcre_regexp);
 296        pcre_free(p->pcre_extra_info);
 297}
 298#else /* !USE_LIBPCRE */
 299static void compile_pcre_regexp(struct grep_pat *p, const struct grep_opt *opt)
 300{
 301        die("cannot use Perl-compatible regexes when not compiled with USE_LIBPCRE");
 302}
 303
 304static int pcrematch(struct grep_pat *p, const char *line, const char *eol,
 305                regmatch_t *match, int eflags)
 306{
 307        return 1;
 308}
 309
 310static void free_pcre_regexp(struct grep_pat *p)
 311{
 312}
 313#endif /* !USE_LIBPCRE */
 314
 315static int is_fixed(const char *s, size_t len)
 316{
 317        size_t i;
 318
 319        /* regcomp cannot accept patterns with NULs so we
 320         * consider any pattern containing a NUL fixed.
 321         */
 322        if (memchr(s, 0, len))
 323                return 1;
 324
 325        for (i = 0; i < len; i++) {
 326                if (is_regex_special(s[i]))
 327                        return 0;
 328        }
 329
 330        return 1;
 331}
 332
 333static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
 334{
 335        int err;
 336
 337        p->word_regexp = opt->word_regexp;
 338        p->ignore_case = opt->ignore_case;
 339
 340        if (opt->fixed || is_fixed(p->pattern, p->patternlen))
 341                p->fixed = 1;
 342        else
 343                p->fixed = 0;
 344
 345        if (p->fixed) {
 346                if (opt->regflags & REG_ICASE || p->ignore_case)
 347                        p->kws = kwsalloc(tolower_trans_tbl);
 348                else
 349                        p->kws = kwsalloc(NULL);
 350                kwsincr(p->kws, p->pattern, p->patternlen);
 351                kwsprep(p->kws);
 352                return;
 353        }
 354
 355        if (opt->pcre) {
 356                compile_pcre_regexp(p, opt);
 357                return;
 358        }
 359
 360        err = regcomp(&p->regexp, p->pattern, opt->regflags);
 361        if (err) {
 362                char errbuf[1024];
 363                regerror(err, &p->regexp, errbuf, 1024);
 364                regfree(&p->regexp);
 365                compile_regexp_failed(p, errbuf);
 366        }
 367}
 368
 369static struct grep_expr *compile_pattern_or(struct grep_pat **);
 370static struct grep_expr *compile_pattern_atom(struct grep_pat **list)
 371{
 372        struct grep_pat *p;
 373        struct grep_expr *x;
 374
 375        p = *list;
 376        if (!p)
 377                return NULL;
 378        switch (p->token) {
 379        case GREP_PATTERN: /* atom */
 380        case GREP_PATTERN_HEAD:
 381        case GREP_PATTERN_BODY:
 382                x = xcalloc(1, sizeof (struct grep_expr));
 383                x->node = GREP_NODE_ATOM;
 384                x->u.atom = p;
 385                *list = p->next;
 386                return x;
 387        case GREP_OPEN_PAREN:
 388                *list = p->next;
 389                x = compile_pattern_or(list);
 390                if (!*list || (*list)->token != GREP_CLOSE_PAREN)
 391                        die("unmatched parenthesis");
 392                *list = (*list)->next;
 393                return x;
 394        default:
 395                return NULL;
 396        }
 397}
 398
 399static struct grep_expr *compile_pattern_not(struct grep_pat **list)
 400{
 401        struct grep_pat *p;
 402        struct grep_expr *x;
 403
 404        p = *list;
 405        if (!p)
 406                return NULL;
 407        switch (p->token) {
 408        case GREP_NOT:
 409                if (!p->next)
 410                        die("--not not followed by pattern expression");
 411                *list = p->next;
 412                x = xcalloc(1, sizeof (struct grep_expr));
 413                x->node = GREP_NODE_NOT;
 414                x->u.unary = compile_pattern_not(list);
 415                if (!x->u.unary)
 416                        die("--not followed by non pattern expression");
 417                return x;
 418        default:
 419                return compile_pattern_atom(list);
 420        }
 421}
 422
 423static struct grep_expr *compile_pattern_and(struct grep_pat **list)
 424{
 425        struct grep_pat *p;
 426        struct grep_expr *x, *y, *z;
 427
 428        x = compile_pattern_not(list);
 429        p = *list;
 430        if (p && p->token == GREP_AND) {
 431                if (!p->next)
 432                        die("--and not followed by pattern expression");
 433                *list = p->next;
 434                y = compile_pattern_and(list);
 435                if (!y)
 436                        die("--and not followed by pattern expression");
 437                z = xcalloc(1, sizeof (struct grep_expr));
 438                z->node = GREP_NODE_AND;
 439                z->u.binary.left = x;
 440                z->u.binary.right = y;
 441                return z;
 442        }
 443        return x;
 444}
 445
 446static struct grep_expr *compile_pattern_or(struct grep_pat **list)
 447{
 448        struct grep_pat *p;
 449        struct grep_expr *x, *y, *z;
 450
 451        x = compile_pattern_and(list);
 452        p = *list;
 453        if (x && p && p->token != GREP_CLOSE_PAREN) {
 454                y = compile_pattern_or(list);
 455                if (!y)
 456                        die("not a pattern expression %s", p->pattern);
 457                z = xcalloc(1, sizeof (struct grep_expr));
 458                z->node = GREP_NODE_OR;
 459                z->u.binary.left = x;
 460                z->u.binary.right = y;
 461                return z;
 462        }
 463        return x;
 464}
 465
 466static struct grep_expr *compile_pattern_expr(struct grep_pat **list)
 467{
 468        return compile_pattern_or(list);
 469}
 470
 471static void indent(int in)
 472{
 473        while (in-- > 0)
 474                fputc(' ', stderr);
 475}
 476
 477static void dump_grep_pat(struct grep_pat *p)
 478{
 479        switch (p->token) {
 480        case GREP_AND: fprintf(stderr, "*and*"); break;
 481        case GREP_OPEN_PAREN: fprintf(stderr, "*(*"); break;
 482        case GREP_CLOSE_PAREN: fprintf(stderr, "*)*"); break;
 483        case GREP_NOT: fprintf(stderr, "*not*"); break;
 484        case GREP_OR: fprintf(stderr, "*or*"); break;
 485
 486        case GREP_PATTERN: fprintf(stderr, "pattern"); break;
 487        case GREP_PATTERN_HEAD: fprintf(stderr, "pattern_head"); break;
 488        case GREP_PATTERN_BODY: fprintf(stderr, "pattern_body"); break;
 489        }
 490
 491        switch (p->token) {
 492        default: break;
 493        case GREP_PATTERN_HEAD:
 494                fprintf(stderr, "<head %d>", p->field); break;
 495        case GREP_PATTERN_BODY:
 496                fprintf(stderr, "<body>"); break;
 497        }
 498        switch (p->token) {
 499        default: break;
 500        case GREP_PATTERN_HEAD:
 501        case GREP_PATTERN_BODY:
 502        case GREP_PATTERN:
 503                fprintf(stderr, "%.*s", (int)p->patternlen, p->pattern);
 504                break;
 505        }
 506        fputc('\n', stderr);
 507}
 508
 509static void dump_grep_expression_1(struct grep_expr *x, int in)
 510{
 511        indent(in);
 512        switch (x->node) {
 513        case GREP_NODE_TRUE:
 514                fprintf(stderr, "true\n");
 515                break;
 516        case GREP_NODE_ATOM:
 517                dump_grep_pat(x->u.atom);
 518                break;
 519        case GREP_NODE_NOT:
 520                fprintf(stderr, "(not\n");
 521                dump_grep_expression_1(x->u.unary, in+1);
 522                indent(in);
 523                fprintf(stderr, ")\n");
 524                break;
 525        case GREP_NODE_AND:
 526                fprintf(stderr, "(and\n");
 527                dump_grep_expression_1(x->u.binary.left, in+1);
 528                dump_grep_expression_1(x->u.binary.right, in+1);
 529                indent(in);
 530                fprintf(stderr, ")\n");
 531                break;
 532        case GREP_NODE_OR:
 533                fprintf(stderr, "(or\n");
 534                dump_grep_expression_1(x->u.binary.left, in+1);
 535                dump_grep_expression_1(x->u.binary.right, in+1);
 536                indent(in);
 537                fprintf(stderr, ")\n");
 538                break;
 539        }
 540}
 541
 542static void dump_grep_expression(struct grep_opt *opt)
 543{
 544        struct grep_expr *x = opt->pattern_expression;
 545
 546        if (opt->all_match)
 547                fprintf(stderr, "[all-match]\n");
 548        dump_grep_expression_1(x, 0);
 549        fflush(NULL);
 550}
 551
 552static struct grep_expr *grep_true_expr(void)
 553{
 554        struct grep_expr *z = xcalloc(1, sizeof(*z));
 555        z->node = GREP_NODE_TRUE;
 556        return z;
 557}
 558
 559static struct grep_expr *grep_or_expr(struct grep_expr *left, struct grep_expr *right)
 560{
 561        struct grep_expr *z = xcalloc(1, sizeof(*z));
 562        z->node = GREP_NODE_OR;
 563        z->u.binary.left = left;
 564        z->u.binary.right = right;
 565        return z;
 566}
 567
 568static struct grep_expr *prep_header_patterns(struct grep_opt *opt)
 569{
 570        struct grep_pat *p;
 571        struct grep_expr *header_expr;
 572        struct grep_expr *(header_group[GREP_HEADER_FIELD_MAX]);
 573        enum grep_header_field fld;
 574
 575        if (!opt->header_list)
 576                return NULL;
 577
 578        for (p = opt->header_list; p; p = p->next) {
 579                if (p->token != GREP_PATTERN_HEAD)
 580                        die("bug: a non-header pattern in grep header list.");
 581                if (p->field < 0 || GREP_HEADER_FIELD_MAX <= p->field)
 582                        die("bug: unknown header field %d", p->field);
 583                compile_regexp(p, opt);
 584        }
 585
 586        for (fld = 0; fld < GREP_HEADER_FIELD_MAX; fld++)
 587                header_group[fld] = NULL;
 588
 589        for (p = opt->header_list; p; p = p->next) {
 590                struct grep_expr *h;
 591                struct grep_pat *pp = p;
 592
 593                h = compile_pattern_atom(&pp);
 594                if (!h || pp != p->next)
 595                        die("bug: malformed header expr");
 596                if (!header_group[p->field]) {
 597                        header_group[p->field] = h;
 598                        continue;
 599                }
 600                header_group[p->field] = grep_or_expr(h, header_group[p->field]);
 601        }
 602
 603        header_expr = NULL;
 604
 605        for (fld = 0; fld < GREP_HEADER_FIELD_MAX; fld++) {
 606                if (!header_group[fld])
 607                        continue;
 608                if (!header_expr)
 609                        header_expr = grep_true_expr();
 610                header_expr = grep_or_expr(header_group[fld], header_expr);
 611        }
 612        return header_expr;
 613}
 614
 615static struct grep_expr *grep_splice_or(struct grep_expr *x, struct grep_expr *y)
 616{
 617        struct grep_expr *z = x;
 618
 619        while (x) {
 620                assert(x->node == GREP_NODE_OR);
 621                if (x->u.binary.right &&
 622                    x->u.binary.right->node == GREP_NODE_TRUE) {
 623                        x->u.binary.right = y;
 624                        break;
 625                }
 626                x = x->u.binary.right;
 627        }
 628        return z;
 629}
 630
 631static void compile_grep_patterns_real(struct grep_opt *opt)
 632{
 633        struct grep_pat *p;
 634        struct grep_expr *header_expr = prep_header_patterns(opt);
 635
 636        for (p = opt->pattern_list; p; p = p->next) {
 637                switch (p->token) {
 638                case GREP_PATTERN: /* atom */
 639                case GREP_PATTERN_HEAD:
 640                case GREP_PATTERN_BODY:
 641                        compile_regexp(p, opt);
 642                        break;
 643                default:
 644                        opt->extended = 1;
 645                        break;
 646                }
 647        }
 648
 649        if (opt->all_match || header_expr)
 650                opt->extended = 1;
 651        else if (!opt->extended && !opt->debug)
 652                return;
 653
 654        p = opt->pattern_list;
 655        if (p)
 656                opt->pattern_expression = compile_pattern_expr(&p);
 657        if (p)
 658                die("incomplete pattern expression: %s", p->pattern);
 659
 660        if (!header_expr)
 661                return;
 662
 663        if (!opt->pattern_expression)
 664                opt->pattern_expression = header_expr;
 665        else if (opt->all_match)
 666                opt->pattern_expression = grep_splice_or(header_expr,
 667                                                         opt->pattern_expression);
 668        else
 669                opt->pattern_expression = grep_or_expr(opt->pattern_expression,
 670                                                       header_expr);
 671        opt->all_match = 1;
 672}
 673
 674void compile_grep_patterns(struct grep_opt *opt)
 675{
 676        compile_grep_patterns_real(opt);
 677        if (opt->debug)
 678                dump_grep_expression(opt);
 679}
 680
 681static void free_pattern_expr(struct grep_expr *x)
 682{
 683        switch (x->node) {
 684        case GREP_NODE_TRUE:
 685        case GREP_NODE_ATOM:
 686                break;
 687        case GREP_NODE_NOT:
 688                free_pattern_expr(x->u.unary);
 689                break;
 690        case GREP_NODE_AND:
 691        case GREP_NODE_OR:
 692                free_pattern_expr(x->u.binary.left);
 693                free_pattern_expr(x->u.binary.right);
 694                break;
 695        }
 696        free(x);
 697}
 698
 699void free_grep_patterns(struct grep_opt *opt)
 700{
 701        struct grep_pat *p, *n;
 702
 703        for (p = opt->pattern_list; p; p = n) {
 704                n = p->next;
 705                switch (p->token) {
 706                case GREP_PATTERN: /* atom */
 707                case GREP_PATTERN_HEAD:
 708                case GREP_PATTERN_BODY:
 709                        if (p->kws)
 710                                kwsfree(p->kws);
 711                        else if (p->pcre_regexp)
 712                                free_pcre_regexp(p);
 713                        else
 714                                regfree(&p->regexp);
 715                        free(p->pattern);
 716                        break;
 717                default:
 718                        break;
 719                }
 720                free(p);
 721        }
 722
 723        if (!opt->extended)
 724                return;
 725        free_pattern_expr(opt->pattern_expression);
 726}
 727
 728static char *end_of_line(char *cp, unsigned long *left)
 729{
 730        unsigned long l = *left;
 731        while (l && *cp != '\n') {
 732                l--;
 733                cp++;
 734        }
 735        *left = l;
 736        return cp;
 737}
 738
 739static int word_char(char ch)
 740{
 741        return isalnum(ch) || ch == '_';
 742}
 743
 744static void output_color(struct grep_opt *opt, const void *data, size_t size,
 745                         const char *color)
 746{
 747        if (want_color(opt->color) && color && color[0]) {
 748                opt->output(opt, color, strlen(color));
 749                opt->output(opt, data, size);
 750                opt->output(opt, GIT_COLOR_RESET, strlen(GIT_COLOR_RESET));
 751        } else
 752                opt->output(opt, data, size);
 753}
 754
 755static void output_sep(struct grep_opt *opt, char sign)
 756{
 757        if (opt->null_following_name)
 758                opt->output(opt, "\0", 1);
 759        else
 760                output_color(opt, &sign, 1, opt->color_sep);
 761}
 762
 763static void show_name(struct grep_opt *opt, const char *name)
 764{
 765        output_color(opt, name, strlen(name), opt->color_filename);
 766        opt->output(opt, opt->null_following_name ? "\0" : "\n", 1);
 767}
 768
 769static int fixmatch(struct grep_pat *p, char *line, char *eol,
 770                    regmatch_t *match)
 771{
 772        struct kwsmatch kwsm;
 773        size_t offset = kwsexec(p->kws, line, eol - line, &kwsm);
 774        if (offset == -1) {
 775                match->rm_so = match->rm_eo = -1;
 776                return REG_NOMATCH;
 777        } else {
 778                match->rm_so = offset;
 779                match->rm_eo = match->rm_so + kwsm.size[0];
 780                return 0;
 781        }
 782}
 783
 784static int regmatch(const regex_t *preg, char *line, char *eol,
 785                    regmatch_t *match, int eflags)
 786{
 787#ifdef REG_STARTEND
 788        match->rm_so = 0;
 789        match->rm_eo = eol - line;
 790        eflags |= REG_STARTEND;
 791#endif
 792        return regexec(preg, line, 1, match, eflags);
 793}
 794
 795static int patmatch(struct grep_pat *p, char *line, char *eol,
 796                    regmatch_t *match, int eflags)
 797{
 798        int hit;
 799
 800        if (p->fixed)
 801                hit = !fixmatch(p, line, eol, match);
 802        else if (p->pcre_regexp)
 803                hit = !pcrematch(p, line, eol, match, eflags);
 804        else
 805                hit = !regmatch(&p->regexp, line, eol, match, eflags);
 806
 807        return hit;
 808}
 809
 810static int strip_timestamp(char *bol, char **eol_p)
 811{
 812        char *eol = *eol_p;
 813        int ch;
 814
 815        while (bol < --eol) {
 816                if (*eol != '>')
 817                        continue;
 818                *eol_p = ++eol;
 819                ch = *eol;
 820                *eol = '\0';
 821                return ch;
 822        }
 823        return 0;
 824}
 825
 826static struct {
 827        const char *field;
 828        size_t len;
 829} header_field[] = {
 830        { "author ", 7 },
 831        { "committer ", 10 },
 832        { "reflog ", 7 },
 833};
 834
 835static int match_one_pattern(struct grep_pat *p, char *bol, char *eol,
 836                             enum grep_context ctx,
 837                             regmatch_t *pmatch, int eflags)
 838{
 839        int hit = 0;
 840        int saved_ch = 0;
 841        const char *start = bol;
 842
 843        if ((p->token != GREP_PATTERN) &&
 844            ((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD)))
 845                return 0;
 846
 847        if (p->token == GREP_PATTERN_HEAD) {
 848                const char *field;
 849                size_t len;
 850                assert(p->field < ARRAY_SIZE(header_field));
 851                field = header_field[p->field].field;
 852                len = header_field[p->field].len;
 853                if (strncmp(bol, field, len))
 854                        return 0;
 855                bol += len;
 856                switch (p->field) {
 857                case GREP_HEADER_AUTHOR:
 858                case GREP_HEADER_COMMITTER:
 859                        saved_ch = strip_timestamp(bol, &eol);
 860                        break;
 861                default:
 862                        break;
 863                }
 864        }
 865
 866 again:
 867        hit = patmatch(p, bol, eol, pmatch, eflags);
 868
 869        if (hit && p->word_regexp) {
 870                if ((pmatch[0].rm_so < 0) ||
 871                    (eol - bol) < pmatch[0].rm_so ||
 872                    (pmatch[0].rm_eo < 0) ||
 873                    (eol - bol) < pmatch[0].rm_eo)
 874                        die("regexp returned nonsense");
 875
 876                /* Match beginning must be either beginning of the
 877                 * line, or at word boundary (i.e. the last char must
 878                 * not be a word char).  Similarly, match end must be
 879                 * either end of the line, or at word boundary
 880                 * (i.e. the next char must not be a word char).
 881                 */
 882                if ( ((pmatch[0].rm_so == 0) ||
 883                      !word_char(bol[pmatch[0].rm_so-1])) &&
 884                     ((pmatch[0].rm_eo == (eol-bol)) ||
 885                      !word_char(bol[pmatch[0].rm_eo])) )
 886                        ;
 887                else
 888                        hit = 0;
 889
 890                /* Words consist of at least one character. */
 891                if (pmatch->rm_so == pmatch->rm_eo)
 892                        hit = 0;
 893
 894                if (!hit && pmatch[0].rm_so + bol + 1 < eol) {
 895                        /* There could be more than one match on the
 896                         * line, and the first match might not be
 897                         * strict word match.  But later ones could be!
 898                         * Forward to the next possible start, i.e. the
 899                         * next position following a non-word char.
 900                         */
 901                        bol = pmatch[0].rm_so + bol + 1;
 902                        while (word_char(bol[-1]) && bol < eol)
 903                                bol++;
 904                        eflags |= REG_NOTBOL;
 905                        if (bol < eol)
 906                                goto again;
 907                }
 908        }
 909        if (p->token == GREP_PATTERN_HEAD && saved_ch)
 910                *eol = saved_ch;
 911        if (hit) {
 912                pmatch[0].rm_so += bol - start;
 913                pmatch[0].rm_eo += bol - start;
 914        }
 915        return hit;
 916}
 917
 918static int match_expr_eval(struct grep_expr *x, char *bol, char *eol,
 919                           enum grep_context ctx, int collect_hits)
 920{
 921        int h = 0;
 922        regmatch_t match;
 923
 924        if (!x)
 925                die("Not a valid grep expression");
 926        switch (x->node) {
 927        case GREP_NODE_TRUE:
 928                h = 1;
 929                break;
 930        case GREP_NODE_ATOM:
 931                h = match_one_pattern(x->u.atom, bol, eol, ctx, &match, 0);
 932                break;
 933        case GREP_NODE_NOT:
 934                h = !match_expr_eval(x->u.unary, bol, eol, ctx, 0);
 935                break;
 936        case GREP_NODE_AND:
 937                if (!match_expr_eval(x->u.binary.left, bol, eol, ctx, 0))
 938                        return 0;
 939                h = match_expr_eval(x->u.binary.right, bol, eol, ctx, 0);
 940                break;
 941        case GREP_NODE_OR:
 942                if (!collect_hits)
 943                        return (match_expr_eval(x->u.binary.left,
 944                                                bol, eol, ctx, 0) ||
 945                                match_expr_eval(x->u.binary.right,
 946                                                bol, eol, ctx, 0));
 947                h = match_expr_eval(x->u.binary.left, bol, eol, ctx, 0);
 948                x->u.binary.left->hit |= h;
 949                h |= match_expr_eval(x->u.binary.right, bol, eol, ctx, 1);
 950                break;
 951        default:
 952                die("Unexpected node type (internal error) %d", x->node);
 953        }
 954        if (collect_hits)
 955                x->hit |= h;
 956        return h;
 957}
 958
 959static int match_expr(struct grep_opt *opt, char *bol, char *eol,
 960                      enum grep_context ctx, int collect_hits)
 961{
 962        struct grep_expr *x = opt->pattern_expression;
 963        return match_expr_eval(x, bol, eol, ctx, collect_hits);
 964}
 965
 966static int match_line(struct grep_opt *opt, char *bol, char *eol,
 967                      enum grep_context ctx, int collect_hits)
 968{
 969        struct grep_pat *p;
 970        regmatch_t match;
 971
 972        if (opt->extended)
 973                return match_expr(opt, bol, eol, ctx, collect_hits);
 974
 975        /* we do not call with collect_hits without being extended */
 976        for (p = opt->pattern_list; p; p = p->next) {
 977                if (match_one_pattern(p, bol, eol, ctx, &match, 0))
 978                        return 1;
 979        }
 980        return 0;
 981}
 982
 983static int match_next_pattern(struct grep_pat *p, char *bol, char *eol,
 984                              enum grep_context ctx,
 985                              regmatch_t *pmatch, int eflags)
 986{
 987        regmatch_t match;
 988
 989        if (!match_one_pattern(p, bol, eol, ctx, &match, eflags))
 990                return 0;
 991        if (match.rm_so < 0 || match.rm_eo < 0)
 992                return 0;
 993        if (pmatch->rm_so >= 0 && pmatch->rm_eo >= 0) {
 994                if (match.rm_so > pmatch->rm_so)
 995                        return 1;
 996                if (match.rm_so == pmatch->rm_so && match.rm_eo < pmatch->rm_eo)
 997                        return 1;
 998        }
 999        pmatch->rm_so = match.rm_so;
1000        pmatch->rm_eo = match.rm_eo;
1001        return 1;
1002}
1003
1004static int next_match(struct grep_opt *opt, char *bol, char *eol,
1005                      enum grep_context ctx, regmatch_t *pmatch, int eflags)
1006{
1007        struct grep_pat *p;
1008        int hit = 0;
1009
1010        pmatch->rm_so = pmatch->rm_eo = -1;
1011        if (bol < eol) {
1012                for (p = opt->pattern_list; p; p = p->next) {
1013                        switch (p->token) {
1014                        case GREP_PATTERN: /* atom */
1015                        case GREP_PATTERN_HEAD:
1016                        case GREP_PATTERN_BODY:
1017                                hit |= match_next_pattern(p, bol, eol, ctx,
1018                                                          pmatch, eflags);
1019                                break;
1020                        default:
1021                                break;
1022                        }
1023                }
1024        }
1025        return hit;
1026}
1027
1028static void show_line(struct grep_opt *opt, char *bol, char *eol,
1029                      const char *name, unsigned lno, char sign)
1030{
1031        int rest = eol - bol;
1032        char *line_color = NULL;
1033
1034        if (opt->file_break && opt->last_shown == 0) {
1035                if (opt->show_hunk_mark)
1036                        opt->output(opt, "\n", 1);
1037        } else if (opt->pre_context || opt->post_context || opt->funcbody) {
1038                if (opt->last_shown == 0) {
1039                        if (opt->show_hunk_mark) {
1040                                output_color(opt, "--", 2, opt->color_sep);
1041                                opt->output(opt, "\n", 1);
1042                        }
1043                } else if (lno > opt->last_shown + 1) {
1044                        output_color(opt, "--", 2, opt->color_sep);
1045                        opt->output(opt, "\n", 1);
1046                }
1047        }
1048        if (opt->heading && opt->last_shown == 0) {
1049                output_color(opt, name, strlen(name), opt->color_filename);
1050                opt->output(opt, "\n", 1);
1051        }
1052        opt->last_shown = lno;
1053
1054        if (!opt->heading && opt->pathname) {
1055                output_color(opt, name, strlen(name), opt->color_filename);
1056                output_sep(opt, sign);
1057        }
1058        if (opt->linenum) {
1059                char buf[32];
1060                snprintf(buf, sizeof(buf), "%d", lno);
1061                output_color(opt, buf, strlen(buf), opt->color_lineno);
1062                output_sep(opt, sign);
1063        }
1064        if (opt->color) {
1065                regmatch_t match;
1066                enum grep_context ctx = GREP_CONTEXT_BODY;
1067                int ch = *eol;
1068                int eflags = 0;
1069
1070                if (sign == ':')
1071                        line_color = opt->color_selected;
1072                else if (sign == '-')
1073                        line_color = opt->color_context;
1074                else if (sign == '=')
1075                        line_color = opt->color_function;
1076                *eol = '\0';
1077                while (next_match(opt, bol, eol, ctx, &match, eflags)) {
1078                        if (match.rm_so == match.rm_eo)
1079                                break;
1080
1081                        output_color(opt, bol, match.rm_so, line_color);
1082                        output_color(opt, bol + match.rm_so,
1083                                     match.rm_eo - match.rm_so,
1084                                     opt->color_match);
1085                        bol += match.rm_eo;
1086                        rest -= match.rm_eo;
1087                        eflags = REG_NOTBOL;
1088                }
1089                *eol = ch;
1090        }
1091        output_color(opt, bol, rest, line_color);
1092        opt->output(opt, "\n", 1);
1093}
1094
1095#ifndef NO_PTHREADS
1096int grep_use_locks;
1097
1098/*
1099 * This lock protects access to the gitattributes machinery, which is
1100 * not thread-safe.
1101 */
1102pthread_mutex_t grep_attr_mutex;
1103
1104static inline void grep_attr_lock(void)
1105{
1106        if (grep_use_locks)
1107                pthread_mutex_lock(&grep_attr_mutex);
1108}
1109
1110static inline void grep_attr_unlock(void)
1111{
1112        if (grep_use_locks)
1113                pthread_mutex_unlock(&grep_attr_mutex);
1114}
1115
1116/*
1117 * Same as git_attr_mutex, but protecting the thread-unsafe object db access.
1118 */
1119pthread_mutex_t grep_read_mutex;
1120
1121#else
1122#define grep_attr_lock()
1123#define grep_attr_unlock()
1124#endif
1125
1126static int match_funcname(struct grep_opt *opt, struct grep_source *gs, char *bol, char *eol)
1127{
1128        xdemitconf_t *xecfg = opt->priv;
1129        if (xecfg && !xecfg->find_func) {
1130                grep_source_load_driver(gs);
1131                if (gs->driver->funcname.pattern) {
1132                        const struct userdiff_funcname *pe = &gs->driver->funcname;
1133                        xdiff_set_find_func(xecfg, pe->pattern, pe->cflags);
1134                } else {
1135                        xecfg = opt->priv = NULL;
1136                }
1137        }
1138
1139        if (xecfg) {
1140                char buf[1];
1141                return xecfg->find_func(bol, eol - bol, buf, 1,
1142                                        xecfg->find_func_priv) >= 0;
1143        }
1144
1145        if (bol == eol)
1146                return 0;
1147        if (isalpha(*bol) || *bol == '_' || *bol == '$')
1148                return 1;
1149        return 0;
1150}
1151
1152static void show_funcname_line(struct grep_opt *opt, struct grep_source *gs,
1153                               char *bol, unsigned lno)
1154{
1155        while (bol > gs->buf) {
1156                char *eol = --bol;
1157
1158                while (bol > gs->buf && bol[-1] != '\n')
1159                        bol--;
1160                lno--;
1161
1162                if (lno <= opt->last_shown)
1163                        break;
1164
1165                if (match_funcname(opt, gs, bol, eol)) {
1166                        show_line(opt, bol, eol, gs->name, lno, '=');
1167                        break;
1168                }
1169        }
1170}
1171
1172static void show_pre_context(struct grep_opt *opt, struct grep_source *gs,
1173                             char *bol, char *end, unsigned lno)
1174{
1175        unsigned cur = lno, from = 1, funcname_lno = 0;
1176        int funcname_needed = !!opt->funcname;
1177
1178        if (opt->funcbody && !match_funcname(opt, gs, bol, end))
1179                funcname_needed = 2;
1180
1181        if (opt->pre_context < lno)
1182                from = lno - opt->pre_context;
1183        if (from <= opt->last_shown)
1184                from = opt->last_shown + 1;
1185
1186        /* Rewind. */
1187        while (bol > gs->buf &&
1188               cur > (funcname_needed == 2 ? opt->last_shown + 1 : from)) {
1189                char *eol = --bol;
1190
1191                while (bol > gs->buf && bol[-1] != '\n')
1192                        bol--;
1193                cur--;
1194                if (funcname_needed && match_funcname(opt, gs, bol, eol)) {
1195                        funcname_lno = cur;
1196                        funcname_needed = 0;
1197                }
1198        }
1199
1200        /* We need to look even further back to find a function signature. */
1201        if (opt->funcname && funcname_needed)
1202                show_funcname_line(opt, gs, bol, cur);
1203
1204        /* Back forward. */
1205        while (cur < lno) {
1206                char *eol = bol, sign = (cur == funcname_lno) ? '=' : '-';
1207
1208                while (*eol != '\n')
1209                        eol++;
1210                show_line(opt, bol, eol, gs->name, cur, sign);
1211                bol = eol + 1;
1212                cur++;
1213        }
1214}
1215
1216static int should_lookahead(struct grep_opt *opt)
1217{
1218        struct grep_pat *p;
1219
1220        if (opt->extended)
1221                return 0; /* punt for too complex stuff */
1222        if (opt->invert)
1223                return 0;
1224        for (p = opt->pattern_list; p; p = p->next) {
1225                if (p->token != GREP_PATTERN)
1226                        return 0; /* punt for "header only" and stuff */
1227        }
1228        return 1;
1229}
1230
1231static int look_ahead(struct grep_opt *opt,
1232                      unsigned long *left_p,
1233                      unsigned *lno_p,
1234                      char **bol_p)
1235{
1236        unsigned lno = *lno_p;
1237        char *bol = *bol_p;
1238        struct grep_pat *p;
1239        char *sp, *last_bol;
1240        regoff_t earliest = -1;
1241
1242        for (p = opt->pattern_list; p; p = p->next) {
1243                int hit;
1244                regmatch_t m;
1245
1246                hit = patmatch(p, bol, bol + *left_p, &m, 0);
1247                if (!hit || m.rm_so < 0 || m.rm_eo < 0)
1248                        continue;
1249                if (earliest < 0 || m.rm_so < earliest)
1250                        earliest = m.rm_so;
1251        }
1252
1253        if (earliest < 0) {
1254                *bol_p = bol + *left_p;
1255                *left_p = 0;
1256                return 1;
1257        }
1258        for (sp = bol + earliest; bol < sp && sp[-1] != '\n'; sp--)
1259                ; /* find the beginning of the line */
1260        last_bol = sp;
1261
1262        for (sp = bol; sp < last_bol; sp++) {
1263                if (*sp == '\n')
1264                        lno++;
1265        }
1266        *left_p -= last_bol - bol;
1267        *bol_p = last_bol;
1268        *lno_p = lno;
1269        return 0;
1270}
1271
1272static void std_output(struct grep_opt *opt, const void *buf, size_t size)
1273{
1274        fwrite(buf, size, 1, stdout);
1275}
1276
1277static int grep_source_1(struct grep_opt *opt, struct grep_source *gs, int collect_hits)
1278{
1279        char *bol;
1280        unsigned long left;
1281        unsigned lno = 1;
1282        unsigned last_hit = 0;
1283        int binary_match_only = 0;
1284        unsigned count = 0;
1285        int try_lookahead = 0;
1286        int show_function = 0;
1287        enum grep_context ctx = GREP_CONTEXT_HEAD;
1288        xdemitconf_t xecfg;
1289
1290        if (!opt->output)
1291                opt->output = std_output;
1292
1293        if (opt->pre_context || opt->post_context || opt->file_break ||
1294            opt->funcbody) {
1295                /* Show hunk marks, except for the first file. */
1296                if (opt->last_shown)
1297                        opt->show_hunk_mark = 1;
1298                /*
1299                 * If we're using threads then we can't easily identify
1300                 * the first file.  Always put hunk marks in that case
1301                 * and skip the very first one later in work_done().
1302                 */
1303                if (opt->output != std_output)
1304                        opt->show_hunk_mark = 1;
1305        }
1306        opt->last_shown = 0;
1307
1308        switch (opt->binary) {
1309        case GREP_BINARY_DEFAULT:
1310                if (grep_source_is_binary(gs))
1311                        binary_match_only = 1;
1312                break;
1313        case GREP_BINARY_NOMATCH:
1314                if (grep_source_is_binary(gs))
1315                        return 0; /* Assume unmatch */
1316                break;
1317        case GREP_BINARY_TEXT:
1318                break;
1319        default:
1320                die("bug: unknown binary handling mode");
1321        }
1322
1323        memset(&xecfg, 0, sizeof(xecfg));
1324        opt->priv = &xecfg;
1325
1326        try_lookahead = should_lookahead(opt);
1327
1328        if (grep_source_load(gs) < 0)
1329                return 0;
1330
1331        bol = gs->buf;
1332        left = gs->size;
1333        while (left) {
1334                char *eol, ch;
1335                int hit;
1336
1337                /*
1338                 * look_ahead() skips quickly to the line that possibly
1339                 * has the next hit; don't call it if we need to do
1340                 * something more than just skipping the current line
1341                 * in response to an unmatch for the current line.  E.g.
1342                 * inside a post-context window, we will show the current
1343                 * line as a context around the previous hit when it
1344                 * doesn't hit.
1345                 */
1346                if (try_lookahead
1347                    && !(last_hit
1348                         && (show_function ||
1349                             lno <= last_hit + opt->post_context))
1350                    && look_ahead(opt, &left, &lno, &bol))
1351                        break;
1352                eol = end_of_line(bol, &left);
1353                ch = *eol;
1354                *eol = 0;
1355
1356                if ((ctx == GREP_CONTEXT_HEAD) && (eol == bol))
1357                        ctx = GREP_CONTEXT_BODY;
1358
1359                hit = match_line(opt, bol, eol, ctx, collect_hits);
1360                *eol = ch;
1361
1362                if (collect_hits)
1363                        goto next_line;
1364
1365                /* "grep -v -e foo -e bla" should list lines
1366                 * that do not have either, so inversion should
1367                 * be done outside.
1368                 */
1369                if (opt->invert)
1370                        hit = !hit;
1371                if (opt->unmatch_name_only) {
1372                        if (hit)
1373                                return 0;
1374                        goto next_line;
1375                }
1376                if (hit) {
1377                        count++;
1378                        if (opt->status_only)
1379                                return 1;
1380                        if (opt->name_only) {
1381                                show_name(opt, gs->name);
1382                                return 1;
1383                        }
1384                        if (opt->count)
1385                                goto next_line;
1386                        if (binary_match_only) {
1387                                opt->output(opt, "Binary file ", 12);
1388                                output_color(opt, gs->name, strlen(gs->name),
1389                                             opt->color_filename);
1390                                opt->output(opt, " matches\n", 9);
1391                                return 1;
1392                        }
1393                        /* Hit at this line.  If we haven't shown the
1394                         * pre-context lines, we would need to show them.
1395                         */
1396                        if (opt->pre_context || opt->funcbody)
1397                                show_pre_context(opt, gs, bol, eol, lno);
1398                        else if (opt->funcname)
1399                                show_funcname_line(opt, gs, bol, lno);
1400                        show_line(opt, bol, eol, gs->name, lno, ':');
1401                        last_hit = lno;
1402                        if (opt->funcbody)
1403                                show_function = 1;
1404                        goto next_line;
1405                }
1406                if (show_function && match_funcname(opt, gs, bol, eol))
1407                        show_function = 0;
1408                if (show_function ||
1409                    (last_hit && lno <= last_hit + opt->post_context)) {
1410                        /* If the last hit is within the post context,
1411                         * we need to show this line.
1412                         */
1413                        show_line(opt, bol, eol, gs->name, lno, '-');
1414                }
1415
1416        next_line:
1417                bol = eol + 1;
1418                if (!left)
1419                        break;
1420                left--;
1421                lno++;
1422        }
1423
1424        if (collect_hits)
1425                return 0;
1426
1427        if (opt->status_only)
1428                return 0;
1429        if (opt->unmatch_name_only) {
1430                /* We did not see any hit, so we want to show this */
1431                show_name(opt, gs->name);
1432                return 1;
1433        }
1434
1435        xdiff_clear_find_func(&xecfg);
1436        opt->priv = NULL;
1437
1438        /* NEEDSWORK:
1439         * The real "grep -c foo *.c" gives many "bar.c:0" lines,
1440         * which feels mostly useless but sometimes useful.  Maybe
1441         * make it another option?  For now suppress them.
1442         */
1443        if (opt->count && count) {
1444                char buf[32];
1445                output_color(opt, gs->name, strlen(gs->name), opt->color_filename);
1446                output_sep(opt, ':');
1447                snprintf(buf, sizeof(buf), "%u\n", count);
1448                opt->output(opt, buf, strlen(buf));
1449                return 1;
1450        }
1451        return !!last_hit;
1452}
1453
1454static void clr_hit_marker(struct grep_expr *x)
1455{
1456        /* All-hit markers are meaningful only at the very top level
1457         * OR node.
1458         */
1459        while (1) {
1460                x->hit = 0;
1461                if (x->node != GREP_NODE_OR)
1462                        return;
1463                x->u.binary.left->hit = 0;
1464                x = x->u.binary.right;
1465        }
1466}
1467
1468static int chk_hit_marker(struct grep_expr *x)
1469{
1470        /* Top level nodes have hit markers.  See if they all are hits */
1471        while (1) {
1472                if (x->node != GREP_NODE_OR)
1473                        return x->hit;
1474                if (!x->u.binary.left->hit)
1475                        return 0;
1476                x = x->u.binary.right;
1477        }
1478}
1479
1480int grep_source(struct grep_opt *opt, struct grep_source *gs)
1481{
1482        /*
1483         * we do not have to do the two-pass grep when we do not check
1484         * buffer-wide "all-match".
1485         */
1486        if (!opt->all_match)
1487                return grep_source_1(opt, gs, 0);
1488
1489        /* Otherwise the toplevel "or" terms hit a bit differently.
1490         * We first clear hit markers from them.
1491         */
1492        clr_hit_marker(opt->pattern_expression);
1493        grep_source_1(opt, gs, 1);
1494
1495        if (!chk_hit_marker(opt->pattern_expression))
1496                return 0;
1497
1498        return grep_source_1(opt, gs, 0);
1499}
1500
1501int grep_buffer(struct grep_opt *opt, char *buf, unsigned long size)
1502{
1503        struct grep_source gs;
1504        int r;
1505
1506        grep_source_init(&gs, GREP_SOURCE_BUF, NULL, NULL);
1507        gs.buf = buf;
1508        gs.size = size;
1509
1510        r = grep_source(opt, &gs);
1511
1512        grep_source_clear(&gs);
1513        return r;
1514}
1515
1516void grep_source_init(struct grep_source *gs, enum grep_source_type type,
1517                      const char *name, const void *identifier)
1518{
1519        gs->type = type;
1520        gs->name = name ? xstrdup(name) : NULL;
1521        gs->buf = NULL;
1522        gs->size = 0;
1523        gs->driver = NULL;
1524
1525        switch (type) {
1526        case GREP_SOURCE_FILE:
1527                gs->identifier = xstrdup(identifier);
1528                break;
1529        case GREP_SOURCE_SHA1:
1530                gs->identifier = xmalloc(20);
1531                memcpy(gs->identifier, identifier, 20);
1532                break;
1533        case GREP_SOURCE_BUF:
1534                gs->identifier = NULL;
1535        }
1536}
1537
1538void grep_source_clear(struct grep_source *gs)
1539{
1540        free(gs->name);
1541        gs->name = NULL;
1542        free(gs->identifier);
1543        gs->identifier = NULL;
1544        grep_source_clear_data(gs);
1545}
1546
1547void grep_source_clear_data(struct grep_source *gs)
1548{
1549        switch (gs->type) {
1550        case GREP_SOURCE_FILE:
1551        case GREP_SOURCE_SHA1:
1552                free(gs->buf);
1553                gs->buf = NULL;
1554                gs->size = 0;
1555                break;
1556        case GREP_SOURCE_BUF:
1557                /* leave user-provided buf intact */
1558                break;
1559        }
1560}
1561
1562static int grep_source_load_sha1(struct grep_source *gs)
1563{
1564        enum object_type type;
1565
1566        grep_read_lock();
1567        gs->buf = read_sha1_file(gs->identifier, &type, &gs->size);
1568        grep_read_unlock();
1569
1570        if (!gs->buf)
1571                return error(_("'%s': unable to read %s"),
1572                             gs->name,
1573                             sha1_to_hex(gs->identifier));
1574        return 0;
1575}
1576
1577static int grep_source_load_file(struct grep_source *gs)
1578{
1579        const char *filename = gs->identifier;
1580        struct stat st;
1581        char *data;
1582        size_t size;
1583        int i;
1584
1585        if (lstat(filename, &st) < 0) {
1586        err_ret:
1587                if (errno != ENOENT)
1588                        error(_("'%s': %s"), filename, strerror(errno));
1589                return -1;
1590        }
1591        if (!S_ISREG(st.st_mode))
1592                return -1;
1593        size = xsize_t(st.st_size);
1594        i = open(filename, O_RDONLY);
1595        if (i < 0)
1596                goto err_ret;
1597        data = xmalloc(size + 1);
1598        if (st.st_size != read_in_full(i, data, size)) {
1599                error(_("'%s': short read %s"), filename, strerror(errno));
1600                close(i);
1601                free(data);
1602                return -1;
1603        }
1604        close(i);
1605        data[size] = 0;
1606
1607        gs->buf = data;
1608        gs->size = size;
1609        return 0;
1610}
1611
1612static int grep_source_load(struct grep_source *gs)
1613{
1614        if (gs->buf)
1615                return 0;
1616
1617        switch (gs->type) {
1618        case GREP_SOURCE_FILE:
1619                return grep_source_load_file(gs);
1620        case GREP_SOURCE_SHA1:
1621                return grep_source_load_sha1(gs);
1622        case GREP_SOURCE_BUF:
1623                return gs->buf ? 0 : -1;
1624        }
1625        die("BUG: invalid grep_source type");
1626}
1627
1628void grep_source_load_driver(struct grep_source *gs)
1629{
1630        if (gs->driver)
1631                return;
1632
1633        grep_attr_lock();
1634        gs->driver = userdiff_find_by_path(gs->name);
1635        if (!gs->driver)
1636                gs->driver = userdiff_find_by_name("default");
1637        grep_attr_unlock();
1638}
1639
1640static int grep_source_is_binary(struct grep_source *gs)
1641{
1642        grep_source_load_driver(gs);
1643        if (gs->driver->binary != -1)
1644                return gs->driver->binary;
1645
1646        if (!grep_source_load(gs))
1647                return buffer_is_binary(gs->buf, gs->size);
1648
1649        return 0;
1650}