grep.con commit grep: prepare for new header field filter (ad4813b)
   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
   9
  10static struct grep_pat *create_grep_pat(const char *pat, size_t patlen,
  11                                        const char *origin, int no,
  12                                        enum grep_pat_token t,
  13                                        enum grep_header_field field)
  14{
  15        struct grep_pat *p = xcalloc(1, sizeof(*p));
  16        p->pattern = xmemdupz(pat, patlen);
  17        p->patternlen = patlen;
  18        p->origin = origin;
  19        p->no = no;
  20        p->token = t;
  21        p->field = field;
  22        return p;
  23}
  24
  25static void do_append_grep_pat(struct grep_pat ***tail, struct grep_pat *p)
  26{
  27        **tail = p;
  28        *tail = &p->next;
  29        p->next = NULL;
  30
  31        switch (p->token) {
  32        case GREP_PATTERN: /* atom */
  33        case GREP_PATTERN_HEAD:
  34        case GREP_PATTERN_BODY:
  35                for (;;) {
  36                        struct grep_pat *new_pat;
  37                        size_t len = 0;
  38                        char *cp = p->pattern + p->patternlen, *nl = NULL;
  39                        while (++len <= p->patternlen) {
  40                                if (*(--cp) == '\n') {
  41                                        nl = cp;
  42                                        break;
  43                                }
  44                        }
  45                        if (!nl)
  46                                break;
  47                        new_pat = create_grep_pat(nl + 1, len - 1, p->origin,
  48                                                  p->no, p->token, p->field);
  49                        new_pat->next = p->next;
  50                        if (!p->next)
  51                                *tail = &new_pat->next;
  52                        p->next = new_pat;
  53                        *nl = '\0';
  54                        p->patternlen -= len;
  55                }
  56                break;
  57        default:
  58                break;
  59        }
  60}
  61
  62void append_header_grep_pattern(struct grep_opt *opt,
  63                                enum grep_header_field field, const char *pat)
  64{
  65        struct grep_pat *p = create_grep_pat(pat, strlen(pat), "header", 0,
  66                                             GREP_PATTERN_HEAD, field);
  67        do_append_grep_pat(&opt->header_tail, p);
  68}
  69
  70void append_grep_pattern(struct grep_opt *opt, const char *pat,
  71                         const char *origin, int no, enum grep_pat_token t)
  72{
  73        append_grep_pat(opt, pat, strlen(pat), origin, no, t);
  74}
  75
  76void append_grep_pat(struct grep_opt *opt, const char *pat, size_t patlen,
  77                     const char *origin, int no, enum grep_pat_token t)
  78{
  79        struct grep_pat *p = create_grep_pat(pat, patlen, origin, no, t, 0);
  80        do_append_grep_pat(&opt->pattern_tail, p);
  81}
  82
  83struct grep_opt *grep_opt_dup(const struct grep_opt *opt)
  84{
  85        struct grep_pat *pat;
  86        struct grep_opt *ret = xmalloc(sizeof(struct grep_opt));
  87        *ret = *opt;
  88
  89        ret->pattern_list = NULL;
  90        ret->pattern_tail = &ret->pattern_list;
  91
  92        for(pat = opt->pattern_list; pat != NULL; pat = pat->next)
  93        {
  94                if(pat->token == GREP_PATTERN_HEAD)
  95                        append_header_grep_pattern(ret, pat->field,
  96                                                   pat->pattern);
  97                else
  98                        append_grep_pat(ret, pat->pattern, pat->patternlen,
  99                                        pat->origin, pat->no, pat->token);
 100        }
 101
 102        return ret;
 103}
 104
 105static NORETURN void compile_regexp_failed(const struct grep_pat *p,
 106                const char *error)
 107{
 108        char where[1024];
 109
 110        if (p->no)
 111                sprintf(where, "In '%s' at %d, ", p->origin, p->no);
 112        else if (p->origin)
 113                sprintf(where, "%s, ", p->origin);
 114        else
 115                where[0] = 0;
 116
 117        die("%s'%s': %s", where, p->pattern, error);
 118}
 119
 120#ifdef USE_LIBPCRE
 121static void compile_pcre_regexp(struct grep_pat *p, const struct grep_opt *opt)
 122{
 123        const char *error;
 124        int erroffset;
 125        int options = PCRE_MULTILINE;
 126
 127        if (opt->ignore_case)
 128                options |= PCRE_CASELESS;
 129
 130        p->pcre_regexp = pcre_compile(p->pattern, options, &error, &erroffset,
 131                        NULL);
 132        if (!p->pcre_regexp)
 133                compile_regexp_failed(p, error);
 134
 135        p->pcre_extra_info = pcre_study(p->pcre_regexp, 0, &error);
 136        if (!p->pcre_extra_info && error)
 137                die("%s", error);
 138}
 139
 140static int pcrematch(struct grep_pat *p, const char *line, const char *eol,
 141                regmatch_t *match, int eflags)
 142{
 143        int ovector[30], ret, flags = 0;
 144
 145        if (eflags & REG_NOTBOL)
 146                flags |= PCRE_NOTBOL;
 147
 148        ret = pcre_exec(p->pcre_regexp, p->pcre_extra_info, line, eol - line,
 149                        0, flags, ovector, ARRAY_SIZE(ovector));
 150        if (ret < 0 && ret != PCRE_ERROR_NOMATCH)
 151                die("pcre_exec failed with error code %d", ret);
 152        if (ret > 0) {
 153                ret = 0;
 154                match->rm_so = ovector[0];
 155                match->rm_eo = ovector[1];
 156        }
 157
 158        return ret;
 159}
 160
 161static void free_pcre_regexp(struct grep_pat *p)
 162{
 163        pcre_free(p->pcre_regexp);
 164        pcre_free(p->pcre_extra_info);
 165}
 166#else /* !USE_LIBPCRE */
 167static void compile_pcre_regexp(struct grep_pat *p, const struct grep_opt *opt)
 168{
 169        die("cannot use Perl-compatible regexes when not compiled with USE_LIBPCRE");
 170}
 171
 172static int pcrematch(struct grep_pat *p, const char *line, const char *eol,
 173                regmatch_t *match, int eflags)
 174{
 175        return 1;
 176}
 177
 178static void free_pcre_regexp(struct grep_pat *p)
 179{
 180}
 181#endif /* !USE_LIBPCRE */
 182
 183static int is_fixed(const char *s, size_t len)
 184{
 185        size_t i;
 186
 187        /* regcomp cannot accept patterns with NULs so we
 188         * consider any pattern containing a NUL fixed.
 189         */
 190        if (memchr(s, 0, len))
 191                return 1;
 192
 193        for (i = 0; i < len; i++) {
 194                if (is_regex_special(s[i]))
 195                        return 0;
 196        }
 197
 198        return 1;
 199}
 200
 201static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
 202{
 203        int err;
 204
 205        p->word_regexp = opt->word_regexp;
 206        p->ignore_case = opt->ignore_case;
 207
 208        if (opt->fixed || is_fixed(p->pattern, p->patternlen))
 209                p->fixed = 1;
 210        else
 211                p->fixed = 0;
 212
 213        if (p->fixed) {
 214                if (opt->regflags & REG_ICASE || p->ignore_case)
 215                        p->kws = kwsalloc(tolower_trans_tbl);
 216                else
 217                        p->kws = kwsalloc(NULL);
 218                kwsincr(p->kws, p->pattern, p->patternlen);
 219                kwsprep(p->kws);
 220                return;
 221        }
 222
 223        if (opt->pcre) {
 224                compile_pcre_regexp(p, opt);
 225                return;
 226        }
 227
 228        err = regcomp(&p->regexp, p->pattern, opt->regflags);
 229        if (err) {
 230                char errbuf[1024];
 231                regerror(err, &p->regexp, errbuf, 1024);
 232                regfree(&p->regexp);
 233                compile_regexp_failed(p, errbuf);
 234        }
 235}
 236
 237static struct grep_expr *compile_pattern_or(struct grep_pat **);
 238static struct grep_expr *compile_pattern_atom(struct grep_pat **list)
 239{
 240        struct grep_pat *p;
 241        struct grep_expr *x;
 242
 243        p = *list;
 244        if (!p)
 245                return NULL;
 246        switch (p->token) {
 247        case GREP_PATTERN: /* atom */
 248        case GREP_PATTERN_HEAD:
 249        case GREP_PATTERN_BODY:
 250                x = xcalloc(1, sizeof (struct grep_expr));
 251                x->node = GREP_NODE_ATOM;
 252                x->u.atom = p;
 253                *list = p->next;
 254                return x;
 255        case GREP_OPEN_PAREN:
 256                *list = p->next;
 257                x = compile_pattern_or(list);
 258                if (!*list || (*list)->token != GREP_CLOSE_PAREN)
 259                        die("unmatched parenthesis");
 260                *list = (*list)->next;
 261                return x;
 262        default:
 263                return NULL;
 264        }
 265}
 266
 267static struct grep_expr *compile_pattern_not(struct grep_pat **list)
 268{
 269        struct grep_pat *p;
 270        struct grep_expr *x;
 271
 272        p = *list;
 273        if (!p)
 274                return NULL;
 275        switch (p->token) {
 276        case GREP_NOT:
 277                if (!p->next)
 278                        die("--not not followed by pattern expression");
 279                *list = p->next;
 280                x = xcalloc(1, sizeof (struct grep_expr));
 281                x->node = GREP_NODE_NOT;
 282                x->u.unary = compile_pattern_not(list);
 283                if (!x->u.unary)
 284                        die("--not followed by non pattern expression");
 285                return x;
 286        default:
 287                return compile_pattern_atom(list);
 288        }
 289}
 290
 291static struct grep_expr *compile_pattern_and(struct grep_pat **list)
 292{
 293        struct grep_pat *p;
 294        struct grep_expr *x, *y, *z;
 295
 296        x = compile_pattern_not(list);
 297        p = *list;
 298        if (p && p->token == GREP_AND) {
 299                if (!p->next)
 300                        die("--and not followed by pattern expression");
 301                *list = p->next;
 302                y = compile_pattern_and(list);
 303                if (!y)
 304                        die("--and not followed by pattern expression");
 305                z = xcalloc(1, sizeof (struct grep_expr));
 306                z->node = GREP_NODE_AND;
 307                z->u.binary.left = x;
 308                z->u.binary.right = y;
 309                return z;
 310        }
 311        return x;
 312}
 313
 314static struct grep_expr *compile_pattern_or(struct grep_pat **list)
 315{
 316        struct grep_pat *p;
 317        struct grep_expr *x, *y, *z;
 318
 319        x = compile_pattern_and(list);
 320        p = *list;
 321        if (x && p && p->token != GREP_CLOSE_PAREN) {
 322                y = compile_pattern_or(list);
 323                if (!y)
 324                        die("not a pattern expression %s", p->pattern);
 325                z = xcalloc(1, sizeof (struct grep_expr));
 326                z->node = GREP_NODE_OR;
 327                z->u.binary.left = x;
 328                z->u.binary.right = y;
 329                return z;
 330        }
 331        return x;
 332}
 333
 334static struct grep_expr *compile_pattern_expr(struct grep_pat **list)
 335{
 336        return compile_pattern_or(list);
 337}
 338
 339static void indent(int in)
 340{
 341        while (in-- > 0)
 342                fputc(' ', stderr);
 343}
 344
 345static void dump_grep_pat(struct grep_pat *p)
 346{
 347        switch (p->token) {
 348        case GREP_AND: fprintf(stderr, "*and*"); break;
 349        case GREP_OPEN_PAREN: fprintf(stderr, "*(*"); break;
 350        case GREP_CLOSE_PAREN: fprintf(stderr, "*)*"); break;
 351        case GREP_NOT: fprintf(stderr, "*not*"); break;
 352        case GREP_OR: fprintf(stderr, "*or*"); break;
 353
 354        case GREP_PATTERN: fprintf(stderr, "pattern"); break;
 355        case GREP_PATTERN_HEAD: fprintf(stderr, "pattern_head"); break;
 356        case GREP_PATTERN_BODY: fprintf(stderr, "pattern_body"); break;
 357        }
 358
 359        switch (p->token) {
 360        default: break;
 361        case GREP_PATTERN_HEAD:
 362                fprintf(stderr, "<head %d>", p->field); break;
 363        case GREP_PATTERN_BODY:
 364                fprintf(stderr, "<body>"); break;
 365        }
 366        switch (p->token) {
 367        default: break;
 368        case GREP_PATTERN_HEAD:
 369        case GREP_PATTERN_BODY:
 370        case GREP_PATTERN:
 371                fprintf(stderr, "%.*s", (int)p->patternlen, p->pattern);
 372                break;
 373        }
 374        fputc('\n', stderr);
 375}
 376
 377static void dump_grep_expression_1(struct grep_expr *x, int in)
 378{
 379        indent(in);
 380        switch (x->node) {
 381        case GREP_NODE_TRUE:
 382                fprintf(stderr, "true\n");
 383                break;
 384        case GREP_NODE_ATOM:
 385                dump_grep_pat(x->u.atom);
 386                break;
 387        case GREP_NODE_NOT:
 388                fprintf(stderr, "(not\n");
 389                dump_grep_expression_1(x->u.unary, in+1);
 390                indent(in);
 391                fprintf(stderr, ")\n");
 392                break;
 393        case GREP_NODE_AND:
 394                fprintf(stderr, "(and\n");
 395                dump_grep_expression_1(x->u.binary.left, in+1);
 396                dump_grep_expression_1(x->u.binary.right, in+1);
 397                indent(in);
 398                fprintf(stderr, ")\n");
 399                break;
 400        case GREP_NODE_OR:
 401                fprintf(stderr, "(or\n");
 402                dump_grep_expression_1(x->u.binary.left, in+1);
 403                dump_grep_expression_1(x->u.binary.right, in+1);
 404                indent(in);
 405                fprintf(stderr, ")\n");
 406                break;
 407        }
 408}
 409
 410static void dump_grep_expression(struct grep_opt *opt)
 411{
 412        struct grep_expr *x = opt->pattern_expression;
 413
 414        if (opt->all_match)
 415                fprintf(stderr, "[all-match]\n");
 416        dump_grep_expression_1(x, 0);
 417        fflush(NULL);
 418}
 419
 420static struct grep_expr *grep_true_expr(void)
 421{
 422        struct grep_expr *z = xcalloc(1, sizeof(*z));
 423        z->node = GREP_NODE_TRUE;
 424        return z;
 425}
 426
 427static struct grep_expr *grep_or_expr(struct grep_expr *left, struct grep_expr *right)
 428{
 429        struct grep_expr *z = xcalloc(1, sizeof(*z));
 430        z->node = GREP_NODE_OR;
 431        z->u.binary.left = left;
 432        z->u.binary.right = right;
 433        return z;
 434}
 435
 436static struct grep_expr *prep_header_patterns(struct grep_opt *opt)
 437{
 438        struct grep_pat *p;
 439        struct grep_expr *header_expr;
 440        struct grep_expr *(header_group[GREP_HEADER_FIELD_MAX]);
 441        enum grep_header_field fld;
 442
 443        if (!opt->header_list)
 444                return NULL;
 445
 446        for (p = opt->header_list; p; p = p->next) {
 447                if (p->token != GREP_PATTERN_HEAD)
 448                        die("bug: a non-header pattern in grep header list.");
 449                if (p->field < 0 || GREP_HEADER_FIELD_MAX <= p->field)
 450                        die("bug: unknown header field %d", p->field);
 451                compile_regexp(p, opt);
 452        }
 453
 454        for (fld = 0; fld < GREP_HEADER_FIELD_MAX; fld++)
 455                header_group[fld] = NULL;
 456
 457        for (p = opt->header_list; p; p = p->next) {
 458                struct grep_expr *h;
 459                struct grep_pat *pp = p;
 460
 461                h = compile_pattern_atom(&pp);
 462                if (!h || pp != p->next)
 463                        die("bug: malformed header expr");
 464                if (!header_group[p->field]) {
 465                        header_group[p->field] = h;
 466                        continue;
 467                }
 468                header_group[p->field] = grep_or_expr(h, header_group[p->field]);
 469        }
 470
 471        header_expr = NULL;
 472
 473        for (fld = 0; fld < GREP_HEADER_FIELD_MAX; fld++) {
 474                if (!header_group[fld])
 475                        continue;
 476                if (!header_expr)
 477                        header_expr = grep_true_expr();
 478                header_expr = grep_or_expr(header_group[fld], header_expr);
 479        }
 480        return header_expr;
 481}
 482
 483static struct grep_expr *grep_splice_or(struct grep_expr *x, struct grep_expr *y)
 484{
 485        struct grep_expr *z = x;
 486
 487        while (x) {
 488                assert(x->node == GREP_NODE_OR);
 489                if (x->u.binary.right &&
 490                    x->u.binary.right->node == GREP_NODE_TRUE) {
 491                        x->u.binary.right = y;
 492                        break;
 493                }
 494                x = x->u.binary.right;
 495        }
 496        return z;
 497}
 498
 499static void compile_grep_patterns_real(struct grep_opt *opt)
 500{
 501        struct grep_pat *p;
 502        struct grep_expr *header_expr = prep_header_patterns(opt);
 503
 504        for (p = opt->pattern_list; p; p = p->next) {
 505                switch (p->token) {
 506                case GREP_PATTERN: /* atom */
 507                case GREP_PATTERN_HEAD:
 508                case GREP_PATTERN_BODY:
 509                        compile_regexp(p, opt);
 510                        break;
 511                default:
 512                        opt->extended = 1;
 513                        break;
 514                }
 515        }
 516
 517        if (opt->all_match || header_expr)
 518                opt->extended = 1;
 519        else if (!opt->extended && !opt->debug)
 520                return;
 521
 522        p = opt->pattern_list;
 523        if (p)
 524                opt->pattern_expression = compile_pattern_expr(&p);
 525        if (p)
 526                die("incomplete pattern expression: %s", p->pattern);
 527
 528        if (!header_expr)
 529                return;
 530
 531        if (!opt->pattern_expression)
 532                opt->pattern_expression = header_expr;
 533        else if (opt->all_match)
 534                opt->pattern_expression = grep_splice_or(header_expr,
 535                                                         opt->pattern_expression);
 536        else
 537                opt->pattern_expression = grep_or_expr(opt->pattern_expression,
 538                                                       header_expr);
 539        opt->all_match = 1;
 540}
 541
 542void compile_grep_patterns(struct grep_opt *opt)
 543{
 544        compile_grep_patterns_real(opt);
 545        if (opt->debug)
 546                dump_grep_expression(opt);
 547}
 548
 549static void free_pattern_expr(struct grep_expr *x)
 550{
 551        switch (x->node) {
 552        case GREP_NODE_TRUE:
 553        case GREP_NODE_ATOM:
 554                break;
 555        case GREP_NODE_NOT:
 556                free_pattern_expr(x->u.unary);
 557                break;
 558        case GREP_NODE_AND:
 559        case GREP_NODE_OR:
 560                free_pattern_expr(x->u.binary.left);
 561                free_pattern_expr(x->u.binary.right);
 562                break;
 563        }
 564        free(x);
 565}
 566
 567void free_grep_patterns(struct grep_opt *opt)
 568{
 569        struct grep_pat *p, *n;
 570
 571        for (p = opt->pattern_list; p; p = n) {
 572                n = p->next;
 573                switch (p->token) {
 574                case GREP_PATTERN: /* atom */
 575                case GREP_PATTERN_HEAD:
 576                case GREP_PATTERN_BODY:
 577                        if (p->kws)
 578                                kwsfree(p->kws);
 579                        else if (p->pcre_regexp)
 580                                free_pcre_regexp(p);
 581                        else
 582                                regfree(&p->regexp);
 583                        free(p->pattern);
 584                        break;
 585                default:
 586                        break;
 587                }
 588                free(p);
 589        }
 590
 591        if (!opt->extended)
 592                return;
 593        free_pattern_expr(opt->pattern_expression);
 594}
 595
 596static char *end_of_line(char *cp, unsigned long *left)
 597{
 598        unsigned long l = *left;
 599        while (l && *cp != '\n') {
 600                l--;
 601                cp++;
 602        }
 603        *left = l;
 604        return cp;
 605}
 606
 607static int word_char(char ch)
 608{
 609        return isalnum(ch) || ch == '_';
 610}
 611
 612static void output_color(struct grep_opt *opt, const void *data, size_t size,
 613                         const char *color)
 614{
 615        if (want_color(opt->color) && color && color[0]) {
 616                opt->output(opt, color, strlen(color));
 617                opt->output(opt, data, size);
 618                opt->output(opt, GIT_COLOR_RESET, strlen(GIT_COLOR_RESET));
 619        } else
 620                opt->output(opt, data, size);
 621}
 622
 623static void output_sep(struct grep_opt *opt, char sign)
 624{
 625        if (opt->null_following_name)
 626                opt->output(opt, "\0", 1);
 627        else
 628                output_color(opt, &sign, 1, opt->color_sep);
 629}
 630
 631static void show_name(struct grep_opt *opt, const char *name)
 632{
 633        output_color(opt, name, strlen(name), opt->color_filename);
 634        opt->output(opt, opt->null_following_name ? "\0" : "\n", 1);
 635}
 636
 637static int fixmatch(struct grep_pat *p, char *line, char *eol,
 638                    regmatch_t *match)
 639{
 640        struct kwsmatch kwsm;
 641        size_t offset = kwsexec(p->kws, line, eol - line, &kwsm);
 642        if (offset == -1) {
 643                match->rm_so = match->rm_eo = -1;
 644                return REG_NOMATCH;
 645        } else {
 646                match->rm_so = offset;
 647                match->rm_eo = match->rm_so + kwsm.size[0];
 648                return 0;
 649        }
 650}
 651
 652static int regmatch(const regex_t *preg, char *line, char *eol,
 653                    regmatch_t *match, int eflags)
 654{
 655#ifdef REG_STARTEND
 656        match->rm_so = 0;
 657        match->rm_eo = eol - line;
 658        eflags |= REG_STARTEND;
 659#endif
 660        return regexec(preg, line, 1, match, eflags);
 661}
 662
 663static int patmatch(struct grep_pat *p, char *line, char *eol,
 664                    regmatch_t *match, int eflags)
 665{
 666        int hit;
 667
 668        if (p->fixed)
 669                hit = !fixmatch(p, line, eol, match);
 670        else if (p->pcre_regexp)
 671                hit = !pcrematch(p, line, eol, match, eflags);
 672        else
 673                hit = !regmatch(&p->regexp, line, eol, match, eflags);
 674
 675        return hit;
 676}
 677
 678static int strip_timestamp(char *bol, char **eol_p)
 679{
 680        char *eol = *eol_p;
 681        int ch;
 682
 683        while (bol < --eol) {
 684                if (*eol != '>')
 685                        continue;
 686                *eol_p = ++eol;
 687                ch = *eol;
 688                *eol = '\0';
 689                return ch;
 690        }
 691        return 0;
 692}
 693
 694static struct {
 695        const char *field;
 696        size_t len;
 697} header_field[] = {
 698        { "author ", 7 },
 699        { "committer ", 10 },
 700};
 701
 702static int match_one_pattern(struct grep_pat *p, char *bol, char *eol,
 703                             enum grep_context ctx,
 704                             regmatch_t *pmatch, int eflags)
 705{
 706        int hit = 0;
 707        int saved_ch = 0;
 708        const char *start = bol;
 709
 710        if ((p->token != GREP_PATTERN) &&
 711            ((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD)))
 712                return 0;
 713
 714        if (p->token == GREP_PATTERN_HEAD) {
 715                const char *field;
 716                size_t len;
 717                assert(p->field < ARRAY_SIZE(header_field));
 718                field = header_field[p->field].field;
 719                len = header_field[p->field].len;
 720                if (strncmp(bol, field, len))
 721                        return 0;
 722                bol += len;
 723                switch (p->field) {
 724                case GREP_HEADER_AUTHOR:
 725                case GREP_HEADER_COMMITTER:
 726                        saved_ch = strip_timestamp(bol, &eol);
 727                        break;
 728                default:
 729                        break;
 730                }
 731        }
 732
 733 again:
 734        hit = patmatch(p, bol, eol, pmatch, eflags);
 735
 736        if (hit && p->word_regexp) {
 737                if ((pmatch[0].rm_so < 0) ||
 738                    (eol - bol) < pmatch[0].rm_so ||
 739                    (pmatch[0].rm_eo < 0) ||
 740                    (eol - bol) < pmatch[0].rm_eo)
 741                        die("regexp returned nonsense");
 742
 743                /* Match beginning must be either beginning of the
 744                 * line, or at word boundary (i.e. the last char must
 745                 * not be a word char).  Similarly, match end must be
 746                 * either end of the line, or at word boundary
 747                 * (i.e. the next char must not be a word char).
 748                 */
 749                if ( ((pmatch[0].rm_so == 0) ||
 750                      !word_char(bol[pmatch[0].rm_so-1])) &&
 751                     ((pmatch[0].rm_eo == (eol-bol)) ||
 752                      !word_char(bol[pmatch[0].rm_eo])) )
 753                        ;
 754                else
 755                        hit = 0;
 756
 757                /* Words consist of at least one character. */
 758                if (pmatch->rm_so == pmatch->rm_eo)
 759                        hit = 0;
 760
 761                if (!hit && pmatch[0].rm_so + bol + 1 < eol) {
 762                        /* There could be more than one match on the
 763                         * line, and the first match might not be
 764                         * strict word match.  But later ones could be!
 765                         * Forward to the next possible start, i.e. the
 766                         * next position following a non-word char.
 767                         */
 768                        bol = pmatch[0].rm_so + bol + 1;
 769                        while (word_char(bol[-1]) && bol < eol)
 770                                bol++;
 771                        eflags |= REG_NOTBOL;
 772                        if (bol < eol)
 773                                goto again;
 774                }
 775        }
 776        if (p->token == GREP_PATTERN_HEAD && saved_ch)
 777                *eol = saved_ch;
 778        if (hit) {
 779                pmatch[0].rm_so += bol - start;
 780                pmatch[0].rm_eo += bol - start;
 781        }
 782        return hit;
 783}
 784
 785static int match_expr_eval(struct grep_expr *x, char *bol, char *eol,
 786                           enum grep_context ctx, int collect_hits)
 787{
 788        int h = 0;
 789        regmatch_t match;
 790
 791        if (!x)
 792                die("Not a valid grep expression");
 793        switch (x->node) {
 794        case GREP_NODE_TRUE:
 795                h = 1;
 796                break;
 797        case GREP_NODE_ATOM:
 798                h = match_one_pattern(x->u.atom, bol, eol, ctx, &match, 0);
 799                break;
 800        case GREP_NODE_NOT:
 801                h = !match_expr_eval(x->u.unary, bol, eol, ctx, 0);
 802                break;
 803        case GREP_NODE_AND:
 804                if (!match_expr_eval(x->u.binary.left, bol, eol, ctx, 0))
 805                        return 0;
 806                h = match_expr_eval(x->u.binary.right, bol, eol, ctx, 0);
 807                break;
 808        case GREP_NODE_OR:
 809                if (!collect_hits)
 810                        return (match_expr_eval(x->u.binary.left,
 811                                                bol, eol, ctx, 0) ||
 812                                match_expr_eval(x->u.binary.right,
 813                                                bol, eol, ctx, 0));
 814                h = match_expr_eval(x->u.binary.left, bol, eol, ctx, 0);
 815                x->u.binary.left->hit |= h;
 816                h |= match_expr_eval(x->u.binary.right, bol, eol, ctx, 1);
 817                break;
 818        default:
 819                die("Unexpected node type (internal error) %d", x->node);
 820        }
 821        if (collect_hits)
 822                x->hit |= h;
 823        return h;
 824}
 825
 826static int match_expr(struct grep_opt *opt, char *bol, char *eol,
 827                      enum grep_context ctx, int collect_hits)
 828{
 829        struct grep_expr *x = opt->pattern_expression;
 830        return match_expr_eval(x, bol, eol, ctx, collect_hits);
 831}
 832
 833static int match_line(struct grep_opt *opt, char *bol, char *eol,
 834                      enum grep_context ctx, int collect_hits)
 835{
 836        struct grep_pat *p;
 837        regmatch_t match;
 838
 839        if (opt->extended)
 840                return match_expr(opt, bol, eol, ctx, collect_hits);
 841
 842        /* we do not call with collect_hits without being extended */
 843        for (p = opt->pattern_list; p; p = p->next) {
 844                if (match_one_pattern(p, bol, eol, ctx, &match, 0))
 845                        return 1;
 846        }
 847        return 0;
 848}
 849
 850static int match_next_pattern(struct grep_pat *p, char *bol, char *eol,
 851                              enum grep_context ctx,
 852                              regmatch_t *pmatch, int eflags)
 853{
 854        regmatch_t match;
 855
 856        if (!match_one_pattern(p, bol, eol, ctx, &match, eflags))
 857                return 0;
 858        if (match.rm_so < 0 || match.rm_eo < 0)
 859                return 0;
 860        if (pmatch->rm_so >= 0 && pmatch->rm_eo >= 0) {
 861                if (match.rm_so > pmatch->rm_so)
 862                        return 1;
 863                if (match.rm_so == pmatch->rm_so && match.rm_eo < pmatch->rm_eo)
 864                        return 1;
 865        }
 866        pmatch->rm_so = match.rm_so;
 867        pmatch->rm_eo = match.rm_eo;
 868        return 1;
 869}
 870
 871static int next_match(struct grep_opt *opt, char *bol, char *eol,
 872                      enum grep_context ctx, regmatch_t *pmatch, int eflags)
 873{
 874        struct grep_pat *p;
 875        int hit = 0;
 876
 877        pmatch->rm_so = pmatch->rm_eo = -1;
 878        if (bol < eol) {
 879                for (p = opt->pattern_list; p; p = p->next) {
 880                        switch (p->token) {
 881                        case GREP_PATTERN: /* atom */
 882                        case GREP_PATTERN_HEAD:
 883                        case GREP_PATTERN_BODY:
 884                                hit |= match_next_pattern(p, bol, eol, ctx,
 885                                                          pmatch, eflags);
 886                                break;
 887                        default:
 888                                break;
 889                        }
 890                }
 891        }
 892        return hit;
 893}
 894
 895static void show_line(struct grep_opt *opt, char *bol, char *eol,
 896                      const char *name, unsigned lno, char sign)
 897{
 898        int rest = eol - bol;
 899        char *line_color = NULL;
 900
 901        if (opt->file_break && opt->last_shown == 0) {
 902                if (opt->show_hunk_mark)
 903                        opt->output(opt, "\n", 1);
 904        } else if (opt->pre_context || opt->post_context || opt->funcbody) {
 905                if (opt->last_shown == 0) {
 906                        if (opt->show_hunk_mark) {
 907                                output_color(opt, "--", 2, opt->color_sep);
 908                                opt->output(opt, "\n", 1);
 909                        }
 910                } else if (lno > opt->last_shown + 1) {
 911                        output_color(opt, "--", 2, opt->color_sep);
 912                        opt->output(opt, "\n", 1);
 913                }
 914        }
 915        if (opt->heading && opt->last_shown == 0) {
 916                output_color(opt, name, strlen(name), opt->color_filename);
 917                opt->output(opt, "\n", 1);
 918        }
 919        opt->last_shown = lno;
 920
 921        if (!opt->heading && opt->pathname) {
 922                output_color(opt, name, strlen(name), opt->color_filename);
 923                output_sep(opt, sign);
 924        }
 925        if (opt->linenum) {
 926                char buf[32];
 927                snprintf(buf, sizeof(buf), "%d", lno);
 928                output_color(opt, buf, strlen(buf), opt->color_lineno);
 929                output_sep(opt, sign);
 930        }
 931        if (opt->color) {
 932                regmatch_t match;
 933                enum grep_context ctx = GREP_CONTEXT_BODY;
 934                int ch = *eol;
 935                int eflags = 0;
 936
 937                if (sign == ':')
 938                        line_color = opt->color_selected;
 939                else if (sign == '-')
 940                        line_color = opt->color_context;
 941                else if (sign == '=')
 942                        line_color = opt->color_function;
 943                *eol = '\0';
 944                while (next_match(opt, bol, eol, ctx, &match, eflags)) {
 945                        if (match.rm_so == match.rm_eo)
 946                                break;
 947
 948                        output_color(opt, bol, match.rm_so, line_color);
 949                        output_color(opt, bol + match.rm_so,
 950                                     match.rm_eo - match.rm_so,
 951                                     opt->color_match);
 952                        bol += match.rm_eo;
 953                        rest -= match.rm_eo;
 954                        eflags = REG_NOTBOL;
 955                }
 956                *eol = ch;
 957        }
 958        output_color(opt, bol, rest, line_color);
 959        opt->output(opt, "\n", 1);
 960}
 961
 962#ifndef NO_PTHREADS
 963int grep_use_locks;
 964
 965/*
 966 * This lock protects access to the gitattributes machinery, which is
 967 * not thread-safe.
 968 */
 969pthread_mutex_t grep_attr_mutex;
 970
 971static inline void grep_attr_lock(void)
 972{
 973        if (grep_use_locks)
 974                pthread_mutex_lock(&grep_attr_mutex);
 975}
 976
 977static inline void grep_attr_unlock(void)
 978{
 979        if (grep_use_locks)
 980                pthread_mutex_unlock(&grep_attr_mutex);
 981}
 982
 983/*
 984 * Same as git_attr_mutex, but protecting the thread-unsafe object db access.
 985 */
 986pthread_mutex_t grep_read_mutex;
 987
 988#else
 989#define grep_attr_lock()
 990#define grep_attr_unlock()
 991#endif
 992
 993static int match_funcname(struct grep_opt *opt, struct grep_source *gs, char *bol, char *eol)
 994{
 995        xdemitconf_t *xecfg = opt->priv;
 996        if (xecfg && !xecfg->find_func) {
 997                grep_source_load_driver(gs);
 998                if (gs->driver->funcname.pattern) {
 999                        const struct userdiff_funcname *pe = &gs->driver->funcname;
1000                        xdiff_set_find_func(xecfg, pe->pattern, pe->cflags);
1001                } else {
1002                        xecfg = opt->priv = NULL;
1003                }
1004        }
1005
1006        if (xecfg) {
1007                char buf[1];
1008                return xecfg->find_func(bol, eol - bol, buf, 1,
1009                                        xecfg->find_func_priv) >= 0;
1010        }
1011
1012        if (bol == eol)
1013                return 0;
1014        if (isalpha(*bol) || *bol == '_' || *bol == '$')
1015                return 1;
1016        return 0;
1017}
1018
1019static void show_funcname_line(struct grep_opt *opt, struct grep_source *gs,
1020                               char *bol, unsigned lno)
1021{
1022        while (bol > gs->buf) {
1023                char *eol = --bol;
1024
1025                while (bol > gs->buf && bol[-1] != '\n')
1026                        bol--;
1027                lno--;
1028
1029                if (lno <= opt->last_shown)
1030                        break;
1031
1032                if (match_funcname(opt, gs, bol, eol)) {
1033                        show_line(opt, bol, eol, gs->name, lno, '=');
1034                        break;
1035                }
1036        }
1037}
1038
1039static void show_pre_context(struct grep_opt *opt, struct grep_source *gs,
1040                             char *bol, char *end, unsigned lno)
1041{
1042        unsigned cur = lno, from = 1, funcname_lno = 0;
1043        int funcname_needed = !!opt->funcname;
1044
1045        if (opt->funcbody && !match_funcname(opt, gs, bol, end))
1046                funcname_needed = 2;
1047
1048        if (opt->pre_context < lno)
1049                from = lno - opt->pre_context;
1050        if (from <= opt->last_shown)
1051                from = opt->last_shown + 1;
1052
1053        /* Rewind. */
1054        while (bol > gs->buf &&
1055               cur > (funcname_needed == 2 ? opt->last_shown + 1 : from)) {
1056                char *eol = --bol;
1057
1058                while (bol > gs->buf && bol[-1] != '\n')
1059                        bol--;
1060                cur--;
1061                if (funcname_needed && match_funcname(opt, gs, bol, eol)) {
1062                        funcname_lno = cur;
1063                        funcname_needed = 0;
1064                }
1065        }
1066
1067        /* We need to look even further back to find a function signature. */
1068        if (opt->funcname && funcname_needed)
1069                show_funcname_line(opt, gs, bol, cur);
1070
1071        /* Back forward. */
1072        while (cur < lno) {
1073                char *eol = bol, sign = (cur == funcname_lno) ? '=' : '-';
1074
1075                while (*eol != '\n')
1076                        eol++;
1077                show_line(opt, bol, eol, gs->name, cur, sign);
1078                bol = eol + 1;
1079                cur++;
1080        }
1081}
1082
1083static int should_lookahead(struct grep_opt *opt)
1084{
1085        struct grep_pat *p;
1086
1087        if (opt->extended)
1088                return 0; /* punt for too complex stuff */
1089        if (opt->invert)
1090                return 0;
1091        for (p = opt->pattern_list; p; p = p->next) {
1092                if (p->token != GREP_PATTERN)
1093                        return 0; /* punt for "header only" and stuff */
1094        }
1095        return 1;
1096}
1097
1098static int look_ahead(struct grep_opt *opt,
1099                      unsigned long *left_p,
1100                      unsigned *lno_p,
1101                      char **bol_p)
1102{
1103        unsigned lno = *lno_p;
1104        char *bol = *bol_p;
1105        struct grep_pat *p;
1106        char *sp, *last_bol;
1107        regoff_t earliest = -1;
1108
1109        for (p = opt->pattern_list; p; p = p->next) {
1110                int hit;
1111                regmatch_t m;
1112
1113                hit = patmatch(p, bol, bol + *left_p, &m, 0);
1114                if (!hit || m.rm_so < 0 || m.rm_eo < 0)
1115                        continue;
1116                if (earliest < 0 || m.rm_so < earliest)
1117                        earliest = m.rm_so;
1118        }
1119
1120        if (earliest < 0) {
1121                *bol_p = bol + *left_p;
1122                *left_p = 0;
1123                return 1;
1124        }
1125        for (sp = bol + earliest; bol < sp && sp[-1] != '\n'; sp--)
1126                ; /* find the beginning of the line */
1127        last_bol = sp;
1128
1129        for (sp = bol; sp < last_bol; sp++) {
1130                if (*sp == '\n')
1131                        lno++;
1132        }
1133        *left_p -= last_bol - bol;
1134        *bol_p = last_bol;
1135        *lno_p = lno;
1136        return 0;
1137}
1138
1139static void std_output(struct grep_opt *opt, const void *buf, size_t size)
1140{
1141        fwrite(buf, size, 1, stdout);
1142}
1143
1144static int grep_source_1(struct grep_opt *opt, struct grep_source *gs, int collect_hits)
1145{
1146        char *bol;
1147        unsigned long left;
1148        unsigned lno = 1;
1149        unsigned last_hit = 0;
1150        int binary_match_only = 0;
1151        unsigned count = 0;
1152        int try_lookahead = 0;
1153        int show_function = 0;
1154        enum grep_context ctx = GREP_CONTEXT_HEAD;
1155        xdemitconf_t xecfg;
1156
1157        if (!opt->output)
1158                opt->output = std_output;
1159
1160        if (opt->pre_context || opt->post_context || opt->file_break ||
1161            opt->funcbody) {
1162                /* Show hunk marks, except for the first file. */
1163                if (opt->last_shown)
1164                        opt->show_hunk_mark = 1;
1165                /*
1166                 * If we're using threads then we can't easily identify
1167                 * the first file.  Always put hunk marks in that case
1168                 * and skip the very first one later in work_done().
1169                 */
1170                if (opt->output != std_output)
1171                        opt->show_hunk_mark = 1;
1172        }
1173        opt->last_shown = 0;
1174
1175        switch (opt->binary) {
1176        case GREP_BINARY_DEFAULT:
1177                if (grep_source_is_binary(gs))
1178                        binary_match_only = 1;
1179                break;
1180        case GREP_BINARY_NOMATCH:
1181                if (grep_source_is_binary(gs))
1182                        return 0; /* Assume unmatch */
1183                break;
1184        case GREP_BINARY_TEXT:
1185                break;
1186        default:
1187                die("bug: unknown binary handling mode");
1188        }
1189
1190        memset(&xecfg, 0, sizeof(xecfg));
1191        opt->priv = &xecfg;
1192
1193        try_lookahead = should_lookahead(opt);
1194
1195        if (grep_source_load(gs) < 0)
1196                return 0;
1197
1198        bol = gs->buf;
1199        left = gs->size;
1200        while (left) {
1201                char *eol, ch;
1202                int hit;
1203
1204                /*
1205                 * look_ahead() skips quickly to the line that possibly
1206                 * has the next hit; don't call it if we need to do
1207                 * something more than just skipping the current line
1208                 * in response to an unmatch for the current line.  E.g.
1209                 * inside a post-context window, we will show the current
1210                 * line as a context around the previous hit when it
1211                 * doesn't hit.
1212                 */
1213                if (try_lookahead
1214                    && !(last_hit
1215                         && (show_function ||
1216                             lno <= last_hit + opt->post_context))
1217                    && look_ahead(opt, &left, &lno, &bol))
1218                        break;
1219                eol = end_of_line(bol, &left);
1220                ch = *eol;
1221                *eol = 0;
1222
1223                if ((ctx == GREP_CONTEXT_HEAD) && (eol == bol))
1224                        ctx = GREP_CONTEXT_BODY;
1225
1226                hit = match_line(opt, bol, eol, ctx, collect_hits);
1227                *eol = ch;
1228
1229                if (collect_hits)
1230                        goto next_line;
1231
1232                /* "grep -v -e foo -e bla" should list lines
1233                 * that do not have either, so inversion should
1234                 * be done outside.
1235                 */
1236                if (opt->invert)
1237                        hit = !hit;
1238                if (opt->unmatch_name_only) {
1239                        if (hit)
1240                                return 0;
1241                        goto next_line;
1242                }
1243                if (hit) {
1244                        count++;
1245                        if (opt->status_only)
1246                                return 1;
1247                        if (opt->name_only) {
1248                                show_name(opt, gs->name);
1249                                return 1;
1250                        }
1251                        if (opt->count)
1252                                goto next_line;
1253                        if (binary_match_only) {
1254                                opt->output(opt, "Binary file ", 12);
1255                                output_color(opt, gs->name, strlen(gs->name),
1256                                             opt->color_filename);
1257                                opt->output(opt, " matches\n", 9);
1258                                return 1;
1259                        }
1260                        /* Hit at this line.  If we haven't shown the
1261                         * pre-context lines, we would need to show them.
1262                         */
1263                        if (opt->pre_context || opt->funcbody)
1264                                show_pre_context(opt, gs, bol, eol, lno);
1265                        else if (opt->funcname)
1266                                show_funcname_line(opt, gs, bol, lno);
1267                        show_line(opt, bol, eol, gs->name, lno, ':');
1268                        last_hit = lno;
1269                        if (opt->funcbody)
1270                                show_function = 1;
1271                        goto next_line;
1272                }
1273                if (show_function && match_funcname(opt, gs, bol, eol))
1274                        show_function = 0;
1275                if (show_function ||
1276                    (last_hit && lno <= last_hit + opt->post_context)) {
1277                        /* If the last hit is within the post context,
1278                         * we need to show this line.
1279                         */
1280                        show_line(opt, bol, eol, gs->name, lno, '-');
1281                }
1282
1283        next_line:
1284                bol = eol + 1;
1285                if (!left)
1286                        break;
1287                left--;
1288                lno++;
1289        }
1290
1291        if (collect_hits)
1292                return 0;
1293
1294        if (opt->status_only)
1295                return 0;
1296        if (opt->unmatch_name_only) {
1297                /* We did not see any hit, so we want to show this */
1298                show_name(opt, gs->name);
1299                return 1;
1300        }
1301
1302        xdiff_clear_find_func(&xecfg);
1303        opt->priv = NULL;
1304
1305        /* NEEDSWORK:
1306         * The real "grep -c foo *.c" gives many "bar.c:0" lines,
1307         * which feels mostly useless but sometimes useful.  Maybe
1308         * make it another option?  For now suppress them.
1309         */
1310        if (opt->count && count) {
1311                char buf[32];
1312                output_color(opt, gs->name, strlen(gs->name), opt->color_filename);
1313                output_sep(opt, ':');
1314                snprintf(buf, sizeof(buf), "%u\n", count);
1315                opt->output(opt, buf, strlen(buf));
1316                return 1;
1317        }
1318        return !!last_hit;
1319}
1320
1321static void clr_hit_marker(struct grep_expr *x)
1322{
1323        /* All-hit markers are meaningful only at the very top level
1324         * OR node.
1325         */
1326        while (1) {
1327                x->hit = 0;
1328                if (x->node != GREP_NODE_OR)
1329                        return;
1330                x->u.binary.left->hit = 0;
1331                x = x->u.binary.right;
1332        }
1333}
1334
1335static int chk_hit_marker(struct grep_expr *x)
1336{
1337        /* Top level nodes have hit markers.  See if they all are hits */
1338        while (1) {
1339                if (x->node != GREP_NODE_OR)
1340                        return x->hit;
1341                if (!x->u.binary.left->hit)
1342                        return 0;
1343                x = x->u.binary.right;
1344        }
1345}
1346
1347int grep_source(struct grep_opt *opt, struct grep_source *gs)
1348{
1349        /*
1350         * we do not have to do the two-pass grep when we do not check
1351         * buffer-wide "all-match".
1352         */
1353        if (!opt->all_match)
1354                return grep_source_1(opt, gs, 0);
1355
1356        /* Otherwise the toplevel "or" terms hit a bit differently.
1357         * We first clear hit markers from them.
1358         */
1359        clr_hit_marker(opt->pattern_expression);
1360        grep_source_1(opt, gs, 1);
1361
1362        if (!chk_hit_marker(opt->pattern_expression))
1363                return 0;
1364
1365        return grep_source_1(opt, gs, 0);
1366}
1367
1368int grep_buffer(struct grep_opt *opt, char *buf, unsigned long size)
1369{
1370        struct grep_source gs;
1371        int r;
1372
1373        grep_source_init(&gs, GREP_SOURCE_BUF, NULL, NULL);
1374        gs.buf = buf;
1375        gs.size = size;
1376
1377        r = grep_source(opt, &gs);
1378
1379        grep_source_clear(&gs);
1380        return r;
1381}
1382
1383void grep_source_init(struct grep_source *gs, enum grep_source_type type,
1384                      const char *name, const void *identifier)
1385{
1386        gs->type = type;
1387        gs->name = name ? xstrdup(name) : NULL;
1388        gs->buf = NULL;
1389        gs->size = 0;
1390        gs->driver = NULL;
1391
1392        switch (type) {
1393        case GREP_SOURCE_FILE:
1394                gs->identifier = xstrdup(identifier);
1395                break;
1396        case GREP_SOURCE_SHA1:
1397                gs->identifier = xmalloc(20);
1398                memcpy(gs->identifier, identifier, 20);
1399                break;
1400        case GREP_SOURCE_BUF:
1401                gs->identifier = NULL;
1402        }
1403}
1404
1405void grep_source_clear(struct grep_source *gs)
1406{
1407        free(gs->name);
1408        gs->name = NULL;
1409        free(gs->identifier);
1410        gs->identifier = NULL;
1411        grep_source_clear_data(gs);
1412}
1413
1414void grep_source_clear_data(struct grep_source *gs)
1415{
1416        switch (gs->type) {
1417        case GREP_SOURCE_FILE:
1418        case GREP_SOURCE_SHA1:
1419                free(gs->buf);
1420                gs->buf = NULL;
1421                gs->size = 0;
1422                break;
1423        case GREP_SOURCE_BUF:
1424                /* leave user-provided buf intact */
1425                break;
1426        }
1427}
1428
1429static int grep_source_load_sha1(struct grep_source *gs)
1430{
1431        enum object_type type;
1432
1433        grep_read_lock();
1434        gs->buf = read_sha1_file(gs->identifier, &type, &gs->size);
1435        grep_read_unlock();
1436
1437        if (!gs->buf)
1438                return error(_("'%s': unable to read %s"),
1439                             gs->name,
1440                             sha1_to_hex(gs->identifier));
1441        return 0;
1442}
1443
1444static int grep_source_load_file(struct grep_source *gs)
1445{
1446        const char *filename = gs->identifier;
1447        struct stat st;
1448        char *data;
1449        size_t size;
1450        int i;
1451
1452        if (lstat(filename, &st) < 0) {
1453        err_ret:
1454                if (errno != ENOENT)
1455                        error(_("'%s': %s"), filename, strerror(errno));
1456                return -1;
1457        }
1458        if (!S_ISREG(st.st_mode))
1459                return -1;
1460        size = xsize_t(st.st_size);
1461        i = open(filename, O_RDONLY);
1462        if (i < 0)
1463                goto err_ret;
1464        data = xmalloc(size + 1);
1465        if (st.st_size != read_in_full(i, data, size)) {
1466                error(_("'%s': short read %s"), filename, strerror(errno));
1467                close(i);
1468                free(data);
1469                return -1;
1470        }
1471        close(i);
1472        data[size] = 0;
1473
1474        gs->buf = data;
1475        gs->size = size;
1476        return 0;
1477}
1478
1479static int grep_source_load(struct grep_source *gs)
1480{
1481        if (gs->buf)
1482                return 0;
1483
1484        switch (gs->type) {
1485        case GREP_SOURCE_FILE:
1486                return grep_source_load_file(gs);
1487        case GREP_SOURCE_SHA1:
1488                return grep_source_load_sha1(gs);
1489        case GREP_SOURCE_BUF:
1490                return gs->buf ? 0 : -1;
1491        }
1492        die("BUG: invalid grep_source type");
1493}
1494
1495void grep_source_load_driver(struct grep_source *gs)
1496{
1497        if (gs->driver)
1498                return;
1499
1500        grep_attr_lock();
1501        gs->driver = userdiff_find_by_path(gs->name);
1502        if (!gs->driver)
1503                gs->driver = userdiff_find_by_name("default");
1504        grep_attr_unlock();
1505}
1506
1507static int grep_source_is_binary(struct grep_source *gs)
1508{
1509        grep_source_load_driver(gs);
1510        if (gs->driver->binary != -1)
1511                return gs->driver->binary;
1512
1513        if (!grep_source_load(gs))
1514                return buffer_is_binary(gs->buf, gs->size);
1515
1516        return 0;
1517}