grep.c

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