grep.c

   1 #include "cache.h"
   2 #include "config.h"
   3 #include "grep.h"
   4 #include "userdiff.h"
   5 #include "xdiff-interface.h"
   6 #include "diff.h"
   7 #include "diffcore.h"
   8 #include "commit.h"
   9 #include "quote.h"
  10
  11 static int grep_source_load(struct grep_source *gs);
  12 static int grep_source_is_binary(struct grep_source *gs);
  13
  14 static struct grep_opt grep_defaults;
  15
  16 static void std_output(struct grep_opt *opt, const void *buf, size_t size)
  17 {
  18         fwrite(buf, size, 1, stdout);
  19 }
  20
  21 static void color_set(char *dst, const char *color_bytes)
  22 {
  23         xsnprintf(dst, COLOR_MAXLEN, "%s", color_bytes);
  24 }
  25
  26 /*
  27  * Initialize the grep_defaults template with hardcoded defaults.
  28  * We could let the compiler do this, but without C99 initializers
  29  * the code gets unwieldy and unreadable, so...
  30  */
  31 void init_grep_defaults(void)
  32 {
  33         struct grep_opt *opt = &grep_defaults;
  34         static int run_once;
  35
  36         if (run_once)
  37                 return;
  38         run_once++;
  39
  40         memset(opt, 0, sizeof(*opt));
  41         opt->relative = 1;
  42         opt->pathname = 1;
  43         opt->max_depth = -1;
  44         opt->pattern_type_option = GREP_PATTERN_TYPE_UNSPECIFIED;
  45         color_set(opt->color_context, "");
  46         color_set(opt->color_filename, "");
  47         color_set(opt->color_function, "");
  48         color_set(opt->color_lineno, "");
  49         color_set(opt->color_match_context, GIT_COLOR_BOLD_RED);
  50         color_set(opt->color_match_selected, GIT_COLOR_BOLD_RED);
  51         color_set(opt->color_selected, "");
  52         color_set(opt->color_sep, GIT_COLOR_CYAN);
  53         opt->color = -1;
  54         opt->output = std_output;
  55 }
  56
  57 static int parse_pattern_type_arg(const char *opt, const char *arg)
  58 {
  59         if (!strcmp(arg, "default"))
  60                 return GREP_PATTERN_TYPE_UNSPECIFIED;
  61         else if (!strcmp(arg, "basic"))
  62                 return GREP_PATTERN_TYPE_BRE;
  63         else if (!strcmp(arg, "extended"))
  64                 return GREP_PATTERN_TYPE_ERE;
  65         else if (!strcmp(arg, "fixed"))
  66                 return GREP_PATTERN_TYPE_FIXED;
  67         else if (!strcmp(arg, "perl"))
  68                 return GREP_PATTERN_TYPE_PCRE;
  69         die("bad %s argument: %s", opt, arg);
  70 }
  71
  72 /*
  73  * Read the configuration file once and store it in
  74  * the grep_defaults template.
  75  */
  76 int grep_config(const char *var, const char *value, void *cb)
  77 {
  78         struct grep_opt *opt = &grep_defaults;
  79         char *color = NULL;
  80
  81         if (userdiff_config(var, value) < 0)
  82                 return -1;
  83
  84         if (!strcmp(var, "grep.extendedregexp")) {
  85                 opt->extended_regexp_option = git_config_bool(var, value);
  86                 return 0;
  87         }
  88
  89         if (!strcmp(var, "grep.patterntype")) {
  90                 opt->pattern_type_option = parse_pattern_type_arg(var, value);
  91                 return 0;
  92         }
  93
  94         if (!strcmp(var, "grep.linenumber")) {
  95                 opt->linenum = git_config_bool(var, value);
  96                 return 0;
  97         }
  98
  99         if (!strcmp(var, "grep.fullname")) {
 100                 opt->relative = !git_config_bool(var, value);
 101                 return 0;
 102         }
 103
 104         if (!strcmp(var, "color.grep"))
 105                 opt->color = git_config_colorbool(var, value);
 106         else if (!strcmp(var, "color.grep.context"))
 107                 color = opt->color_context;
 108         else if (!strcmp(var, "color.grep.filename"))
 109                 color = opt->color_filename;
 110         else if (!strcmp(var, "color.grep.function"))
 111                 color = opt->color_function;
 112         else if (!strcmp(var, "color.grep.linenumber"))
 113                 color = opt->color_lineno;
 114         else if (!strcmp(var, "color.grep.matchcontext"))
 115                 color = opt->color_match_context;
 116         else if (!strcmp(var, "color.grep.matchselected"))
 117                 color = opt->color_match_selected;
 118         else if (!strcmp(var, "color.grep.selected"))
 119                 color = opt->color_selected;
 120         else if (!strcmp(var, "color.grep.separator"))
 121                 color = opt->color_sep;
 122         else if (!strcmp(var, "color.grep.match")) {
 123                 int rc = 0;
 124                 if (!value)
 125                         return config_error_nonbool(var);
 126                 rc |= color_parse(value, opt->color_match_context);
 127                 rc |= color_parse(value, opt->color_match_selected);
 128                 return rc;
 129         }
 130
 131         if (color) {
 132                 if (!value)
 133                         return config_error_nonbool(var);
 134                 return color_parse(value, color);
 135         }
 136         return 0;
 137 }
 138
 139 /*
 140  * Initialize one instance of grep_opt and copy the
 141  * default values from the template we read the configuration
 142  * information in an earlier call to git_config(grep_config).
 143  */
 144 void grep_init(struct grep_opt *opt, const char *prefix)
 145 {
 146         struct grep_opt *def = &grep_defaults;
 147
 148         memset(opt, 0, sizeof(*opt));
 149         opt->prefix = prefix;
 150         opt->prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
 151         opt->pattern_tail = &opt->pattern_list;
 152         opt->header_tail = &opt->header_list;
 153
 154         opt->color = def->color;
 155         opt->extended_regexp_option = def->extended_regexp_option;
 156         opt->pattern_type_option = def->pattern_type_option;
 157         opt->linenum = def->linenum;
 158         opt->max_depth = def->max_depth;
 159         opt->pathname = def->pathname;
 160         opt->relative = def->relative;
 161         opt->output = def->output;
 162
 163         color_set(opt->color_context, def->color_context);
 164         color_set(opt->color_filename, def->color_filename);
 165         color_set(opt->color_function, def->color_function);
 166         color_set(opt->color_lineno, def->color_lineno);
 167         color_set(opt->color_match_context, def->color_match_context);
 168         color_set(opt->color_match_selected, def->color_match_selected);
 169         color_set(opt->color_selected, def->color_selected);
 170         color_set(opt->color_sep, def->color_sep);
 171 }
 172
 173 static void grep_set_pattern_type_option(enum grep_pattern_type pattern_type, struct grep_opt *opt)
 174 {
 175         /*
 176          * When committing to the pattern type by setting the relevant
 177          * fields in grep_opt it's generally not necessary to zero out
 178          * the fields we're not choosing, since they won't have been
 179          * set by anything. The extended_regexp_option field is the
 180          * only exception to this.
 181          *
 182          * This is because in the process of parsing grep.patternType
 183          * & grep.extendedRegexp we set opt->pattern_type_option and
 184          * opt->extended_regexp_option, respectively. We then
 185          * internally use opt->extended_regexp_option to see if we're
 186          * compiling an ERE. It must be unset if that's not actually
 187          * the case.
 188          */
 189         if (pattern_type != GREP_PATTERN_TYPE_ERE &&
 190             opt->extended_regexp_option)
 191                 opt->extended_regexp_option = 0;
 192
 193         switch (pattern_type) {
 194         case GREP_PATTERN_TYPE_UNSPECIFIED:
 195                 /* fall through */
 196
 197         case GREP_PATTERN_TYPE_BRE:
 198                 break;
 199
 200         case GREP_PATTERN_TYPE_ERE:
 201                 opt->extended_regexp_option = 1;
 202                 break;
 203
 204         case GREP_PATTERN_TYPE_FIXED:
 205                 opt->fixed = 1;
 206                 break;
 207
 208         case GREP_PATTERN_TYPE_PCRE:
 209 #ifdef USE_LIBPCRE2
 210                 opt->pcre2 = 1;
 211 #else
 212                 /*
 213                  * It's important that pcre1 always be assigned to
 214                  * even when there's no USE_LIBPCRE* defined. We still
 215                  * call the PCRE stub function, it just dies with
 216                  * "cannot use Perl-compatible regexes[...]".
 217                  */
 218                 opt->pcre1 = 1;
 219 #endif
 220                 break;
 221         }
 222 }
 223
 224 void grep_commit_pattern_type(enum grep_pattern_type pattern_type, struct grep_opt *opt)
 225 {
 226         if (pattern_type != GREP_PATTERN_TYPE_UNSPECIFIED)
 227                 grep_set_pattern_type_option(pattern_type, opt);
 228         else if (opt->pattern_type_option != GREP_PATTERN_TYPE_UNSPECIFIED)
 229                 grep_set_pattern_type_option(opt->pattern_type_option, opt);
 230         else if (opt->extended_regexp_option)
 231                 /*
 232                  * This branch *must* happen after setting from the
 233                  * opt->pattern_type_option above, we don't want
 234                  * grep.extendedRegexp to override grep.patternType!
 235                  */
 236                 grep_set_pattern_type_option(GREP_PATTERN_TYPE_ERE, opt);
 237 }
 238
 239 static struct grep_pat *create_grep_pat(const char *pat, size_t patlen,
 240                                         const char *origin, int no,
 241                                         enum grep_pat_token t,
 242                                         enum grep_header_field field)
 243 {
 244         struct grep_pat *p = xcalloc(1, sizeof(*p));
 245         p->pattern = xmemdupz(pat, patlen);
 246         p->patternlen = patlen;
 247         p->origin = origin;
 248         p->no = no;
 249         p->token = t;
 250         p->field = field;
 251         return p;
 252 }
 253
 254 static void do_append_grep_pat(struct grep_pat ***tail, struct grep_pat *p)
 255 {
 256         **tail = p;
 257         *tail = &p->next;
 258         p->next = NULL;
 259
 260         switch (p->token) {
 261         case GREP_PATTERN: /* atom */
 262         case GREP_PATTERN_HEAD:
 263         case GREP_PATTERN_BODY:
 264                 for (;;) {
 265                         struct grep_pat *new_pat;
 266                         size_t len = 0;
 267                         char *cp = p->pattern + p->patternlen, *nl = NULL;
 268                         while (++len <= p->patternlen) {
 269                                 if (*(--cp) == '\n') {
 270                                         nl = cp;
 271                                         break;
 272                                 }
 273                         }
 274                         if (!nl)
 275                                 break;
 276                         new_pat = create_grep_pat(nl + 1, len - 1, p->origin,
 277                                                   p->no, p->token, p->field);
 278                         new_pat->next = p->next;
 279                         if (!p->next)
 280                                 *tail = &new_pat->next;
 281                         p->next = new_pat;
 282                         *nl = '\0';
 283                         p->patternlen -= len;
 284                 }
 285                 break;
 286         default:
 287                 break;
 288         }
 289 }
 290
 291 void append_header_grep_pattern(struct grep_opt *opt,
 292                                 enum grep_header_field field, const char *pat)
 293 {
 294         struct grep_pat *p = create_grep_pat(pat, strlen(pat), "header", 0,
 295                                              GREP_PATTERN_HEAD, field);
 296         if (field == GREP_HEADER_REFLOG)
 297                 opt->use_reflog_filter = 1;
 298         do_append_grep_pat(&opt->header_tail, p);
 299 }
 300
 301 void append_grep_pattern(struct grep_opt *opt, const char *pat,
 302                          const char *origin, int no, enum grep_pat_token t)
 303 {
 304         append_grep_pat(opt, pat, strlen(pat), origin, no, t);
 305 }
 306
 307 void append_grep_pat(struct grep_opt *opt, const char *pat, size_t patlen,
 308                      const char *origin, int no, enum grep_pat_token t)
 309 {
 310         struct grep_pat *p = create_grep_pat(pat, patlen, origin, no, t, 0);
 311         do_append_grep_pat(&opt->pattern_tail, p);
 312 }
 313
 314 struct grep_opt *grep_opt_dup(const struct grep_opt *opt)
 315 {
 316         struct grep_pat *pat;
 317         struct grep_opt *ret = xmalloc(sizeof(struct grep_opt));
 318         *ret = *opt;
 319
 320         ret->pattern_list = NULL;
 321         ret->pattern_tail = &ret->pattern_list;
 322
 323         for(pat = opt->pattern_list; pat != NULL; pat = pat->next)
 324         {
 325                 if(pat->token == GREP_PATTERN_HEAD)
 326                         append_header_grep_pattern(ret, pat->field,
 327                                                    pat->pattern);
 328                 else
 329                         append_grep_pat(ret, pat->pattern, pat->patternlen,
 330                                         pat->origin, pat->no, pat->token);
 331         }
 332
 333         return ret;
 334 }
 335
 336 static NORETURN void compile_regexp_failed(const struct grep_pat *p,
 337                 const char *error)
 338 {
 339         char where[1024];
 340
 341         if (p->no)
 342                 xsnprintf(where, sizeof(where), "In '%s' at %d, ", p->origin, p->no);
 343         else if (p->origin)
 344                 xsnprintf(where, sizeof(where), "%s, ", p->origin);
 345         else
 346                 where[0] = 0;
 347
 348         die("%s'%s': %s", where, p->pattern, error);
 349 }
 350
 351 static int is_fixed(const char *s, size_t len)
 352 {
 353         size_t i;
 354
 355         for (i = 0; i < len; i++) {
 356                 if (is_regex_special(s[i]))
 357                         return 0;
 358         }
 359
 360         return 1;
 361 }
 362
 363 static int has_null(const char *s, size_t len)
 364 {
 365         /*
 366          * regcomp cannot accept patterns with NULs so when using it
 367          * we consider any pattern containing a NUL fixed.
 368          */
 369         if (memchr(s, 0, len))
 370                 return 1;
 371
 372         return 0;
 373 }
 374
 375 #ifdef USE_LIBPCRE1
 376 static void compile_pcre1_regexp(struct grep_pat *p, const struct grep_opt *opt)
 377 {
 378         const char *error;
 379         int erroffset;
 380         int options = PCRE_MULTILINE;
 381
 382         if (opt->ignore_case) {
 383                 if (has_non_ascii(p->pattern))
 384                         p->pcre1_tables = pcre_maketables();
 385                 options |= PCRE_CASELESS;
 386         }
 387         if (is_utf8_locale() && has_non_ascii(p->pattern))
 388                 options |= PCRE_UTF8;
 389
 390         p->pcre1_regexp = pcre_compile(p->pattern, options, &error, &erroffset,
 391                                       p->pcre1_tables);
 392         if (!p->pcre1_regexp)
 393                 compile_regexp_failed(p, error);
 394
 395         p->pcre1_extra_info = pcre_study(p->pcre1_regexp, GIT_PCRE_STUDY_JIT_COMPILE, &error);
 396         if (!p->pcre1_extra_info && error)
 397                 die("%s", error);
 398
 399 #ifdef GIT_PCRE1_USE_JIT
 400         pcre_config(PCRE_CONFIG_JIT, &p->pcre1_jit_on);
 401         if (p->pcre1_jit_on == 1) {
 402                 p->pcre1_jit_stack = pcre_jit_stack_alloc(1, 1024 * 1024);
 403                 if (!p->pcre1_jit_stack)
 404                         die("Couldn't allocate PCRE JIT stack");
 405                 pcre_assign_jit_stack(p->pcre1_extra_info, NULL, p->pcre1_jit_stack);
 406         } else if (p->pcre1_jit_on != 0) {
 407                 die("BUG: The pcre1_jit_on variable should be 0 or 1, not %d",
 408                     p->pcre1_jit_on);
 409         }
 410 #endif
 411 }
 412
 413 static int pcre1match(struct grep_pat *p, const char *line, const char *eol,
 414                 regmatch_t *match, int eflags)
 415 {
 416         int ovector[30], ret, flags = 0;
 417
 418         if (eflags & REG_NOTBOL)
 419                 flags |= PCRE_NOTBOL;
 420
 421 #ifdef GIT_PCRE1_USE_JIT
 422         if (p->pcre1_jit_on) {
 423                 ret = pcre_jit_exec(p->pcre1_regexp, p->pcre1_extra_info, line,
 424                                     eol - line, 0, flags, ovector,
 425                                     ARRAY_SIZE(ovector), p->pcre1_jit_stack);
 426         } else
 427 #endif
 428         {
 429                 ret = pcre_exec(p->pcre1_regexp, p->pcre1_extra_info, line,
 430                                 eol - line, 0, flags, ovector,
 431                                 ARRAY_SIZE(ovector));
 432         }
 433
 434         if (ret < 0 && ret != PCRE_ERROR_NOMATCH)
 435                 die("pcre_exec failed with error code %d", ret);
 436         if (ret > 0) {
 437                 ret = 0;
 438                 match->rm_so = ovector[0];
 439                 match->rm_eo = ovector[1];
 440         }
 441
 442         return ret;
 443 }
 444
 445 static void free_pcre1_regexp(struct grep_pat *p)
 446 {
 447         pcre_free(p->pcre1_regexp);
 448 #ifdef GIT_PCRE1_USE_JIT
 449         if (p->pcre1_jit_on) {
 450                 pcre_free_study(p->pcre1_extra_info);
 451                 pcre_jit_stack_free(p->pcre1_jit_stack);
 452         } else
 453 #endif
 454         {
 455                 pcre_free(p->pcre1_extra_info);
 456         }
 457         pcre_free((void *)p->pcre1_tables);
 458 }
 459 #else /* !USE_LIBPCRE1 */
 460 static void compile_pcre1_regexp(struct grep_pat *p, const struct grep_opt *opt)
 461 {
 462         die("cannot use Perl-compatible regexes when not compiled with USE_LIBPCRE");
 463 }
 464
 465 static int pcre1match(struct grep_pat *p, const char *line, const char *eol,
 466                 regmatch_t *match, int eflags)
 467 {
 468         return 1;
 469 }
 470
 471 static void free_pcre1_regexp(struct grep_pat *p)
 472 {
 473 }
 474 #endif /* !USE_LIBPCRE1 */
 475
 476 #ifdef USE_LIBPCRE2
 477 static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt)
 478 {
 479         int error;
 480         PCRE2_UCHAR errbuf[256];
 481         PCRE2_SIZE erroffset;
 482         int options = PCRE2_MULTILINE;
 483         const uint8_t *character_tables = NULL;
 484         int jitret;
 485         int patinforet;
 486         size_t jitsizearg;
 487
 488         assert(opt->pcre2);
 489
 490         p->pcre2_compile_context = NULL;
 491
 492         if (opt->ignore_case) {
 493                 if (has_non_ascii(p->pattern)) {
 494                         character_tables = pcre2_maketables(NULL);
 495                         p->pcre2_compile_context = pcre2_compile_context_create(NULL);
 496                         pcre2_set_character_tables(p->pcre2_compile_context, character_tables);
 497                 }
 498                 options |= PCRE2_CASELESS;
 499         }
 500         if (is_utf8_locale() && has_non_ascii(p->pattern))
 501                 options |= PCRE2_UTF;
 502
 503         p->pcre2_pattern = pcre2_compile((PCRE2_SPTR)p->pattern,
 504                                          p->patternlen, options, &error, &erroffset,
 505                                          p->pcre2_compile_context);
 506
 507         if (p->pcre2_pattern) {
 508                 p->pcre2_match_data = pcre2_match_data_create_from_pattern(p->pcre2_pattern, NULL);
 509                 if (!p->pcre2_match_data)
 510                         die("Couldn't allocate PCRE2 match data");
 511         } else {
 512                 pcre2_get_error_message(error, errbuf, sizeof(errbuf));
 513                 compile_regexp_failed(p, (const char *)&errbuf);
 514         }
 515
 516         pcre2_config(PCRE2_CONFIG_JIT, &p->pcre2_jit_on);
 517         if (p->pcre2_jit_on == 1) {
 518                 jitret = pcre2_jit_compile(p->pcre2_pattern, PCRE2_JIT_COMPLETE);
 519                 if (jitret)
 520                         die("Couldn't JIT the PCRE2 pattern '%s', got '%d'\n", p->pattern, jitret);
 521
 522                 /*
 523                  * The pcre2_config(PCRE2_CONFIG_JIT, ...) call just
 524                  * tells us whether the library itself supports JIT,
 525                  * but to see whether we're going to be actually using
 526                  * JIT we need to extract PCRE2_INFO_JITSIZE from the
 527                  * pattern *after* we do pcre2_jit_compile() above.
 528                  *
 529                  * This is because if the pattern contains the
 530                  * (*NO_JIT) verb (see pcre2syntax(3))
 531                  * pcre2_jit_compile() will exit early with 0. If we
 532                  * then proceed to call pcre2_jit_match() further down
 533                  * the line instead of pcre2_match() we'll either
 534                  * segfault (pre PCRE 10.31) or run into a fatal error
 535                  * (post PCRE2 10.31)
 536                  */
 537                 patinforet = pcre2_pattern_info(p->pcre2_pattern, PCRE2_INFO_JITSIZE, &jitsizearg);
 538                 if (patinforet)
 539                         BUG("pcre2_pattern_info() failed: %d", patinforet);
 540                 if (jitsizearg == 0) {
 541                         p->pcre2_jit_on = 0;
 542                         return;
 543                 }
 544
 545                 p->pcre2_jit_stack = pcre2_jit_stack_create(1, 1024 * 1024, NULL);
 546                 if (!p->pcre2_jit_stack)
 547                         die("Couldn't allocate PCRE2 JIT stack");
 548                 p->pcre2_match_context = pcre2_match_context_create(NULL);
 549                 if (!p->pcre2_match_context)
 550                         die("Couldn't allocate PCRE2 match context");
 551                 pcre2_jit_stack_assign(p->pcre2_match_context, NULL, p->pcre2_jit_stack);
 552         } else if (p->pcre2_jit_on != 0) {
 553                 die("BUG: The pcre2_jit_on variable should be 0 or 1, not %d",
 554                     p->pcre1_jit_on);
 555         }
 556 }
 557
 558 static int pcre2match(struct grep_pat *p, const char *line, const char *eol,
 559                 regmatch_t *match, int eflags)
 560 {
 561         int ret, flags = 0;
 562         PCRE2_SIZE *ovector;
 563         PCRE2_UCHAR errbuf[256];
 564
 565         if (eflags & REG_NOTBOL)
 566                 flags |= PCRE2_NOTBOL;
 567
 568         if (p->pcre2_jit_on)
 569                 ret = pcre2_jit_match(p->pcre2_pattern, (unsigned char *)line,
 570                                       eol - line, 0, flags, p->pcre2_match_data,
 571                                       NULL);
 572         else
 573                 ret = pcre2_match(p->pcre2_pattern, (unsigned char *)line,
 574                                   eol - line, 0, flags, p->pcre2_match_data,
 575                                   NULL);
 576
 577         if (ret < 0 && ret != PCRE2_ERROR_NOMATCH) {
 578                 pcre2_get_error_message(ret, errbuf, sizeof(errbuf));
 579                 die("%s failed with error code %d: %s",
 580                     (p->pcre2_jit_on ? "pcre2_jit_match" : "pcre2_match"), ret,
 581                     errbuf);
 582         }
 583         if (ret > 0) {
 584                 ovector = pcre2_get_ovector_pointer(p->pcre2_match_data);
 585                 ret = 0;
 586                 match->rm_so = (int)ovector[0];
 587                 match->rm_eo = (int)ovector[1];
 588         }
 589
 590         return ret;
 591 }
 592
 593 static void free_pcre2_pattern(struct grep_pat *p)
 594 {
 595         pcre2_compile_context_free(p->pcre2_compile_context);
 596         pcre2_code_free(p->pcre2_pattern);
 597         pcre2_match_data_free(p->pcre2_match_data);
 598         pcre2_jit_stack_free(p->pcre2_jit_stack);
 599         pcre2_match_context_free(p->pcre2_match_context);
 600 }
 601 #else /* !USE_LIBPCRE2 */
 602 static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt)
 603 {
 604         /*
 605          * Unreachable until USE_LIBPCRE2 becomes synonymous with
 606          * USE_LIBPCRE. See the sibling comment in
 607          * grep_set_pattern_type_option().
 608          */
 609         die("cannot use Perl-compatible regexes when not compiled with USE_LIBPCRE");
 610 }
 611
 612 static int pcre2match(struct grep_pat *p, const char *line, const char *eol,
 613                 regmatch_t *match, int eflags)
 614 {
 615         return 1;
 616 }
 617
 618 static void free_pcre2_pattern(struct grep_pat *p)
 619 {
 620 }
 621 #endif /* !USE_LIBPCRE2 */
 622
 623 static void compile_fixed_regexp(struct grep_pat *p, struct grep_opt *opt)
 624 {
 625         struct strbuf sb = STRBUF_INIT;
 626         int err;
 627         int regflags = 0;
 628
 629         basic_regex_quote_buf(&sb, p->pattern);
 630         if (opt->ignore_case)
 631                 regflags |= REG_ICASE;
 632         err = regcomp(&p->regexp, sb.buf, regflags);
 633         if (opt->debug)
 634                 fprintf(stderr, "fixed %s\n", sb.buf);
 635         strbuf_release(&sb);
 636         if (err) {
 637                 char errbuf[1024];
 638                 regerror(err, &p->regexp, errbuf, sizeof(errbuf));
 639                 regfree(&p->regexp);
 640                 compile_regexp_failed(p, errbuf);
 641         }
 642 }
 643
 644 static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
 645 {
 646         int ascii_only;
 647         int err;
 648         int regflags = REG_NEWLINE;
 649
 650         p->word_regexp = opt->word_regexp;
 651         p->ignore_case = opt->ignore_case;
 652         ascii_only     = !has_non_ascii(p->pattern);
 653
 654         /*
 655          * Even when -F (fixed) asks us to do a non-regexp search, we
 656          * may not be able to correctly case-fold when -i
 657          * (ignore-case) is asked (in which case, we'll synthesize a
 658          * regexp to match the pattern that matches regexp special
 659          * characters literally, while ignoring case differences).  On
 660          * the other hand, even without -F, if the pattern does not
 661          * have any regexp special characters and there is no need for
 662          * case-folding search, we can internally turn it into a
 663          * simple string match using kws.  p->fixed tells us if we
 664          * want to use kws.
 665          */
 666         if (opt->fixed ||
 667             has_null(p->pattern, p->patternlen) ||
 668             is_fixed(p->pattern, p->patternlen))
 669                 p->fixed = !p->ignore_case || ascii_only;
 670
 671         if (p->fixed) {
 672                 p->kws = kwsalloc(p->ignore_case ? tolower_trans_tbl : NULL);
 673                 kwsincr(p->kws, p->pattern, p->patternlen);
 674                 kwsprep(p->kws);
 675                 return;
 676         } else if (opt->fixed) {
 677                 /*
 678                  * We come here when the pattern has the non-ascii
 679                  * characters we cannot case-fold, and asked to
 680                  * ignore-case.
 681                  */
 682                 compile_fixed_regexp(p, opt);
 683                 return;
 684         }
 685
 686         if (opt->pcre2) {
 687                 compile_pcre2_pattern(p, opt);
 688                 return;
 689         }
 690
 691         if (opt->pcre1) {
 692                 compile_pcre1_regexp(p, opt);
 693                 return;
 694         }
 695
 696         if (p->ignore_case)
 697                 regflags |= REG_ICASE;
 698         if (opt->extended_regexp_option)
 699                 regflags |= REG_EXTENDED;
 700         err = regcomp(&p->regexp, p->pattern, regflags);
 701         if (err) {
 702                 char errbuf[1024];
 703                 regerror(err, &p->regexp, errbuf, 1024);
 704                 regfree(&p->regexp);
 705                 compile_regexp_failed(p, errbuf);
 706         }
 707 }
 708
 709 static struct grep_expr *compile_pattern_or(struct grep_pat **);
 710 static struct grep_expr *compile_pattern_atom(struct grep_pat **list)
 711 {
 712         struct grep_pat *p;
 713         struct grep_expr *x;
 714
 715         p = *list;
 716         if (!p)
 717                 return NULL;
 718         switch (p->token) {
 719         case GREP_PATTERN: /* atom */
 720         case GREP_PATTERN_HEAD:
 721         case GREP_PATTERN_BODY:
 722                 x = xcalloc(1, sizeof (struct grep_expr));
 723                 x->node = GREP_NODE_ATOM;
 724                 x->u.atom = p;
 725                 *list = p->next;
 726                 return x;
 727         case GREP_OPEN_PAREN:
 728                 *list = p->next;
 729                 x = compile_pattern_or(list);
 730                 if (!*list || (*list)->token != GREP_CLOSE_PAREN)
 731                         die("unmatched parenthesis");
 732                 *list = (*list)->next;
 733                 return x;
 734         default:
 735                 return NULL;
 736         }
 737 }
 738
 739 static struct grep_expr *compile_pattern_not(struct grep_pat **list)
 740 {
 741         struct grep_pat *p;
 742         struct grep_expr *x;
 743
 744         p = *list;
 745         if (!p)
 746                 return NULL;
 747         switch (p->token) {
 748         case GREP_NOT:
 749                 if (!p->next)
 750                         die("--not not followed by pattern expression");
 751                 *list = p->next;
 752                 x = xcalloc(1, sizeof (struct grep_expr));
 753                 x->node = GREP_NODE_NOT;
 754                 x->u.unary = compile_pattern_not(list);
 755                 if (!x->u.unary)
 756                         die("--not followed by non pattern expression");
 757                 return x;
 758         default:
 759                 return compile_pattern_atom(list);
 760         }
 761 }
 762
 763 static struct grep_expr *compile_pattern_and(struct grep_pat **list)
 764 {
 765         struct grep_pat *p;
 766         struct grep_expr *x, *y, *z;
 767
 768         x = compile_pattern_not(list);
 769         p = *list;
 770         if (p && p->token == GREP_AND) {
 771                 if (!p->next)
 772                         die("--and not followed by pattern expression");
 773                 *list = p->next;
 774                 y = compile_pattern_and(list);
 775                 if (!y)
 776                         die("--and not followed by pattern expression");
 777                 z = xcalloc(1, sizeof (struct grep_expr));
 778                 z->node = GREP_NODE_AND;
 779                 z->u.binary.left = x;
 780                 z->u.binary.right = y;
 781                 return z;
 782         }
 783         return x;
 784 }
 785
 786 static struct grep_expr *compile_pattern_or(struct grep_pat **list)
 787 {
 788         struct grep_pat *p;
 789         struct grep_expr *x, *y, *z;
 790
 791         x = compile_pattern_and(list);
 792         p = *list;
 793         if (x && p && p->token != GREP_CLOSE_PAREN) {
 794                 y = compile_pattern_or(list);
 795                 if (!y)
 796                         die("not a pattern expression %s", p->pattern);
 797                 z = xcalloc(1, sizeof (struct grep_expr));
 798                 z->node = GREP_NODE_OR;
 799                 z->u.binary.left = x;
 800                 z->u.binary.right = y;
 801                 return z;
 802         }
 803         return x;
 804 }
 805
 806 static struct grep_expr *compile_pattern_expr(struct grep_pat **list)
 807 {
 808         return compile_pattern_or(list);
 809 }
 810
 811 static void indent(int in)
 812 {
 813         while (in-- > 0)
 814                 fputc(' ', stderr);
 815 }
 816
 817 static void dump_grep_pat(struct grep_pat *p)
 818 {
 819         switch (p->token) {
 820         case GREP_AND: fprintf(stderr, "*and*"); break;
 821         case GREP_OPEN_PAREN: fprintf(stderr, "*(*"); break;
 822         case GREP_CLOSE_PAREN: fprintf(stderr, "*)*"); break;
 823         case GREP_NOT: fprintf(stderr, "*not*"); break;
 824         case GREP_OR: fprintf(stderr, "*or*"); break;
 825
 826         case GREP_PATTERN: fprintf(stderr, "pattern"); break;
 827         case GREP_PATTERN_HEAD: fprintf(stderr, "pattern_head"); break;
 828         case GREP_PATTERN_BODY: fprintf(stderr, "pattern_body"); break;
 829         }
 830
 831         switch (p->token) {
 832         default: break;
 833         case GREP_PATTERN_HEAD:
 834                 fprintf(stderr, "<head %d>", p->field); break;
 835         case GREP_PATTERN_BODY:
 836                 fprintf(stderr, "<body>"); break;
 837         }
 838         switch (p->token) {
 839         default: break;
 840         case GREP_PATTERN_HEAD:
 841         case GREP_PATTERN_BODY:
 842         case GREP_PATTERN:
 843                 fprintf(stderr, "%.*s", (int)p->patternlen, p->pattern);
 844                 break;
 845         }
 846         fputc('\n', stderr);
 847 }
 848
 849 static void dump_grep_expression_1(struct grep_expr *x, int in)
 850 {
 851         indent(in);
 852         switch (x->node) {
 853         case GREP_NODE_TRUE:
 854                 fprintf(stderr, "true\n");
 855                 break;
 856         case GREP_NODE_ATOM:
 857                 dump_grep_pat(x->u.atom);
 858                 break;
 859         case GREP_NODE_NOT:
 860                 fprintf(stderr, "(not\n");
 861                 dump_grep_expression_1(x->u.unary, in+1);
 862                 indent(in);
 863                 fprintf(stderr, ")\n");
 864                 break;
 865         case GREP_NODE_AND:
 866                 fprintf(stderr, "(and\n");
 867                 dump_grep_expression_1(x->u.binary.left, in+1);
 868                 dump_grep_expression_1(x->u.binary.right, in+1);
 869                 indent(in);
 870                 fprintf(stderr, ")\n");
 871                 break;
 872         case GREP_NODE_OR:
 873                 fprintf(stderr, "(or\n");
 874                 dump_grep_expression_1(x->u.binary.left, in+1);
 875                 dump_grep_expression_1(x->u.binary.right, in+1);
 876                 indent(in);
 877                 fprintf(stderr, ")\n");
 878                 break;
 879         }
 880 }
 881
 882 static void dump_grep_expression(struct grep_opt *opt)
 883 {
 884         struct grep_expr *x = opt->pattern_expression;
 885
 886         if (opt->all_match)
 887                 fprintf(stderr, "[all-match]\n");
 888         dump_grep_expression_1(x, 0);
 889         fflush(NULL);
 890 }
 891
 892 static struct grep_expr *grep_true_expr(void)
 893 {
 894         struct grep_expr *z = xcalloc(1, sizeof(*z));
 895         z->node = GREP_NODE_TRUE;
 896         return z;
 897 }
 898
 899 static struct grep_expr *grep_or_expr(struct grep_expr *left, struct grep_expr *right)
 900 {
 901         struct grep_expr *z = xcalloc(1, sizeof(*z));
 902         z->node = GREP_NODE_OR;
 903         z->u.binary.left = left;
 904         z->u.binary.right = right;
 905         return z;
 906 }
 907
 908 static struct grep_expr *prep_header_patterns(struct grep_opt *opt)
 909 {
 910         struct grep_pat *p;
 911         struct grep_expr *header_expr;
 912         struct grep_expr *(header_group[GREP_HEADER_FIELD_MAX]);
 913         enum grep_header_field fld;
 914
 915         if (!opt->header_list)
 916                 return NULL;
 917
 918         for (p = opt->header_list; p; p = p->next) {
 919                 if (p->token != GREP_PATTERN_HEAD)
 920                         die("BUG: a non-header pattern in grep header list.");
 921                 if (p->field < GREP_HEADER_FIELD_MIN ||
 922                     GREP_HEADER_FIELD_MAX <= p->field)
 923                         die("BUG: unknown header field %d", p->field);
 924                 compile_regexp(p, opt);
 925         }
 926
 927         for (fld = 0; fld < GREP_HEADER_FIELD_MAX; fld++)
 928                 header_group[fld] = NULL;
 929
 930         for (p = opt->header_list; p; p = p->next) {
 931                 struct grep_expr *h;
 932                 struct grep_pat *pp = p;
 933
 934                 h = compile_pattern_atom(&pp);
 935                 if (!h || pp != p->next)
 936                         die("BUG: malformed header expr");
 937                 if (!header_group[p->field]) {
 938                         header_group[p->field] = h;
 939                         continue;
 940                 }
 941                 header_group[p->field] = grep_or_expr(h, header_group[p->field]);
 942         }
 943
 944         header_expr = NULL;
 945
 946         for (fld = 0; fld < GREP_HEADER_FIELD_MAX; fld++) {
 947                 if (!header_group[fld])
 948                         continue;
 949                 if (!header_expr)
 950                         header_expr = grep_true_expr();
 951                 header_expr = grep_or_expr(header_group[fld], header_expr);
 952         }
 953         return header_expr;
 954 }
 955
 956 static struct grep_expr *grep_splice_or(struct grep_expr *x, struct grep_expr *y)
 957 {
 958         struct grep_expr *z = x;
 959
 960         while (x) {
 961                 assert(x->node == GREP_NODE_OR);
 962                 if (x->u.binary.right &&
 963                     x->u.binary.right->node == GREP_NODE_TRUE) {
 964                         x->u.binary.right = y;
 965                         break;
 966                 }
 967                 x = x->u.binary.right;
 968         }
 969         return z;
 970 }
 971
 972 static void compile_grep_patterns_real(struct grep_opt *opt)
 973 {
 974         struct grep_pat *p;
 975         struct grep_expr *header_expr = prep_header_patterns(opt);
 976
 977         for (p = opt->pattern_list; p; p = p->next) {
 978                 switch (p->token) {
 979                 case GREP_PATTERN: /* atom */
 980                 case GREP_PATTERN_HEAD:
 981                 case GREP_PATTERN_BODY:
 982                         compile_regexp(p, opt);
 983                         break;
 984                 default:
 985                         opt->extended = 1;
 986                         break;
 987                 }
 988         }
 989
 990         if (opt->all_match || header_expr)
 991                 opt->extended = 1;
 992         else if (!opt->extended && !opt->debug)
 993                 return;
 994
 995         p = opt->pattern_list;
 996         if (p)
 997                 opt->pattern_expression = compile_pattern_expr(&p);
 998         if (p)
 999                 die("incomplete pattern expression: %s", p->pattern);
1000
1001         if (!header_expr)
1002                 return;
1003
1004         if (!opt->pattern_expression)
1005                 opt->pattern_expression = header_expr;
1006         else if (opt->all_match)
1007                 opt->pattern_expression = grep_splice_or(header_expr,
1008                                                          opt->pattern_expression);
1009         else
1010                 opt->pattern_expression = grep_or_expr(opt->pattern_expression,
1011                                                        header_expr);
1012         opt->all_match = 1;
1013 }
1014
1015 void compile_grep_patterns(struct grep_opt *opt)
1016 {
1017         compile_grep_patterns_real(opt);
1018         if (opt->debug)
1019                 dump_grep_expression(opt);
1020 }
1021
1022 static void free_pattern_expr(struct grep_expr *x)
1023 {
1024         switch (x->node) {
1025         case GREP_NODE_TRUE:
1026         case GREP_NODE_ATOM:
1027                 break;
1028         case GREP_NODE_NOT:
1029                 free_pattern_expr(x->u.unary);
1030                 break;
1031         case GREP_NODE_AND:
1032         case GREP_NODE_OR:
1033                 free_pattern_expr(x->u.binary.left);
1034                 free_pattern_expr(x->u.binary.right);
1035                 break;
1036         }
1037         free(x);
1038 }
1039
1040 void free_grep_patterns(struct grep_opt *opt)
1041 {
1042         struct grep_pat *p, *n;
1043
1044         for (p = opt->pattern_list; p; p = n) {
1045                 n = p->next;
1046                 switch (p->token) {
1047                 case GREP_PATTERN: /* atom */
1048                 case GREP_PATTERN_HEAD:
1049                 case GREP_PATTERN_BODY:
1050                         if (p->kws)
1051                                 kwsfree(p->kws);
1052                         else if (p->pcre1_regexp)
1053                                 free_pcre1_regexp(p);
1054                         else if (p->pcre2_pattern)
1055                                 free_pcre2_pattern(p);
1056                         else
1057                                 regfree(&p->regexp);
1058                         free(p->pattern);
1059                         break;
1060                 default:
1061                         break;
1062                 }
1063                 free(p);
1064         }
1065
1066         if (!opt->extended)
1067                 return;
1068         free_pattern_expr(opt->pattern_expression);
1069 }
1070
1071 static char *end_of_line(char *cp, unsigned long *left)
1072 {
1073         unsigned long l = *left;
1074         while (l && *cp != '\n') {
1075                 l--;
1076                 cp++;
1077         }
1078         *left = l;
1079         return cp;
1080 }
1081
1082 static int word_char(char ch)
1083 {
1084         return isalnum(ch) || ch == '_';
1085 }
1086
1087 static void output_color(struct grep_opt *opt, const void *data, size_t size,
1088                          const char *color)
1089 {
1090         if (want_color(opt->color) && color && color[0]) {
1091                 opt->output(opt, color, strlen(color));
1092                 opt->output(opt, data, size);
1093                 opt->output(opt, GIT_COLOR_RESET, strlen(GIT_COLOR_RESET));
1094         } else
1095                 opt->output(opt, data, size);
1096 }
1097
1098 static void output_sep(struct grep_opt *opt, char sign)
1099 {
1100         if (opt->null_following_name)
1101                 opt->output(opt, "\0", 1);
1102         else
1103                 output_color(opt, &sign, 1, opt->color_sep);
1104 }
1105
1106 static void show_name(struct grep_opt *opt, const char *name)
1107 {
1108         output_color(opt, name, strlen(name), opt->color_filename);
1109         opt->output(opt, opt->null_following_name ? "\0" : "\n", 1);
1110 }
1111
1112 static int fixmatch(struct grep_pat *p, char *line, char *eol,
1113                     regmatch_t *match)
1114 {
1115         struct kwsmatch kwsm;
1116         size_t offset = kwsexec(p->kws, line, eol - line, &kwsm);
1117         if (offset == -1) {
1118                 match->rm_so = match->rm_eo = -1;
1119                 return REG_NOMATCH;
1120         } else {
1121                 match->rm_so = offset;
1122                 match->rm_eo = match->rm_so + kwsm.size[0];
1123                 return 0;
1124         }
1125 }
1126
1127 static int patmatch(struct grep_pat *p, char *line, char *eol,
1128                     regmatch_t *match, int eflags)
1129 {
1130         int hit;
1131
1132         if (p->fixed)
1133                 hit = !fixmatch(p, line, eol, match);
1134         else if (p->pcre1_regexp)
1135                 hit = !pcre1match(p, line, eol, match, eflags);
1136         else if (p->pcre2_pattern)
1137                 hit = !pcre2match(p, line, eol, match, eflags);
1138         else
1139                 hit = !regexec_buf(&p->regexp, line, eol - line, 1, match,
1140                                    eflags);
1141
1142         return hit;
1143 }
1144
1145 static int strip_timestamp(char *bol, char **eol_p)
1146 {
1147         char *eol = *eol_p;
1148         int ch;
1149
1150         while (bol < --eol) {
1151                 if (*eol != '>')
1152                         continue;
1153                 *eol_p = ++eol;
1154                 ch = *eol;
1155                 *eol = '\0';
1156                 return ch;
1157         }
1158         return 0;
1159 }
1160
1161 static struct {
1162         const char *field;
1163         size_t len;
1164 } header_field[] = {
1165         { "author ", 7 },
1166         { "committer ", 10 },
1167         { "reflog ", 7 },
1168 };
1169
1170 static int match_one_pattern(struct grep_pat *p, char *bol, char *eol,
1171                              enum grep_context ctx,
1172                              regmatch_t *pmatch, int eflags)
1173 {
1174         int hit = 0;
1175         int saved_ch = 0;
1176         const char *start = bol;
1177
1178         if ((p->token != GREP_PATTERN) &&
1179             ((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD)))
1180                 return 0;
1181
1182         if (p->token == GREP_PATTERN_HEAD) {
1183                 const char *field;
1184                 size_t len;
1185                 assert(p->field < ARRAY_SIZE(header_field));
1186                 field = header_field[p->field].field;
1187                 len = header_field[p->field].len;
1188                 if (strncmp(bol, field, len))
1189                         return 0;
1190                 bol += len;
1191                 switch (p->field) {
1192                 case GREP_HEADER_AUTHOR:
1193                 case GREP_HEADER_COMMITTER:
1194                         saved_ch = strip_timestamp(bol, &eol);
1195                         break;
1196                 default:
1197                         break;
1198                 }
1199         }
1200
1201  again:
1202         hit = patmatch(p, bol, eol, pmatch, eflags);
1203
1204         if (hit && p->word_regexp) {
1205                 if ((pmatch[0].rm_so < 0) ||
1206                     (eol - bol) < pmatch[0].rm_so ||
1207                     (pmatch[0].rm_eo < 0) ||
1208                     (eol - bol) < pmatch[0].rm_eo)
1209                         die("regexp returned nonsense");
1210
1211                 /* Match beginning must be either beginning of the
1212                  * line, or at word boundary (i.e. the last char must
1213                  * not be a word char).  Similarly, match end must be
1214                  * either end of the line, or at word boundary
1215                  * (i.e. the next char must not be a word char).
1216                  */
1217                 if ( ((pmatch[0].rm_so == 0) ||
1218                       !word_char(bol[pmatch[0].rm_so-1])) &&
1219                      ((pmatch[0].rm_eo == (eol-bol)) ||
1220                       !word_char(bol[pmatch[0].rm_eo])) )
1221                         ;
1222                 else
1223                         hit = 0;
1224
1225                 /* Words consist of at least one character. */
1226                 if (pmatch->rm_so == pmatch->rm_eo)
1227                         hit = 0;
1228
1229                 if (!hit && pmatch[0].rm_so + bol + 1 < eol) {
1230                         /* There could be more than one match on the
1231                          * line, and the first match might not be
1232                          * strict word match.  But later ones could be!
1233                          * Forward to the next possible start, i.e. the
1234                          * next position following a non-word char.
1235                          */
1236                         bol = pmatch[0].rm_so + bol + 1;
1237                         while (word_char(bol[-1]) && bol < eol)
1238                                 bol++;
1239                         eflags |= REG_NOTBOL;
1240                         if (bol < eol)
1241                                 goto again;
1242                 }
1243         }
1244         if (p->token == GREP_PATTERN_HEAD && saved_ch)
1245                 *eol = saved_ch;
1246         if (hit) {
1247                 pmatch[0].rm_so += bol - start;
1248                 pmatch[0].rm_eo += bol - start;
1249         }
1250         return hit;
1251 }
1252
1253 static int match_expr_eval(struct grep_expr *x, char *bol, char *eol,
1254                            enum grep_context ctx, int collect_hits)
1255 {
1256         int h = 0;
1257         regmatch_t match;
1258
1259         if (!x)
1260                 die("Not a valid grep expression");
1261         switch (x->node) {
1262         case GREP_NODE_TRUE:
1263                 h = 1;
1264                 break;
1265         case GREP_NODE_ATOM:
1266                 h = match_one_pattern(x->u.atom, bol, eol, ctx, &match, 0);
1267                 break;
1268         case GREP_NODE_NOT:
1269                 h = !match_expr_eval(x->u.unary, bol, eol, ctx, 0);
1270                 break;
1271         case GREP_NODE_AND:
1272                 if (!match_expr_eval(x->u.binary.left, bol, eol, ctx, 0))
1273                         return 0;
1274                 h = match_expr_eval(x->u.binary.right, bol, eol, ctx, 0);
1275                 break;
1276         case GREP_NODE_OR:
1277                 if (!collect_hits)
1278                         return (match_expr_eval(x->u.binary.left,
1279                                                 bol, eol, ctx, 0) ||
1280                                 match_expr_eval(x->u.binary.right,
1281                                                 bol, eol, ctx, 0));
1282                 h = match_expr_eval(x->u.binary.left, bol, eol, ctx, 0);
1283                 x->u.binary.left->hit |= h;
1284                 h |= match_expr_eval(x->u.binary.right, bol, eol, ctx, 1);
1285                 break;
1286         default:
1287                 die("Unexpected node type (internal error) %d", x->node);
1288         }
1289         if (collect_hits)
1290                 x->hit |= h;
1291         return h;
1292 }
1293
1294 static int match_expr(struct grep_opt *opt, char *bol, char *eol,
1295                       enum grep_context ctx, int collect_hits)
1296 {
1297         struct grep_expr *x = opt->pattern_expression;
1298         return match_expr_eval(x, bol, eol, ctx, collect_hits);
1299 }
1300
1301 static int match_line(struct grep_opt *opt, char *bol, char *eol,
1302                       enum grep_context ctx, int collect_hits)
1303 {
1304         struct grep_pat *p;
1305         regmatch_t match;
1306
1307         if (opt->extended)
1308                 return match_expr(opt, bol, eol, ctx, collect_hits);
1309
1310         /* we do not call with collect_hits without being extended */
1311         for (p = opt->pattern_list; p; p = p->next) {
1312                 if (match_one_pattern(p, bol, eol, ctx, &match, 0))
1313                         return 1;
1314         }
1315         return 0;
1316 }
1317
1318 static int match_next_pattern(struct grep_pat *p, char *bol, char *eol,
1319                               enum grep_context ctx,
1320                               regmatch_t *pmatch, int eflags)
1321 {
1322         regmatch_t match;
1323
1324         if (!match_one_pattern(p, bol, eol, ctx, &match, eflags))
1325                 return 0;
1326         if (match.rm_so < 0 || match.rm_eo < 0)
1327                 return 0;
1328         if (pmatch->rm_so >= 0 && pmatch->rm_eo >= 0) {
1329                 if (match.rm_so > pmatch->rm_so)
1330                         return 1;
1331                 if (match.rm_so == pmatch->rm_so && match.rm_eo < pmatch->rm_eo)
1332                         return 1;
1333         }
1334         pmatch->rm_so = match.rm_so;
1335         pmatch->rm_eo = match.rm_eo;
1336         return 1;
1337 }
1338
1339 static int next_match(struct grep_opt *opt, char *bol, char *eol,
1340                       enum grep_context ctx, regmatch_t *pmatch, int eflags)
1341 {
1342         struct grep_pat *p;
1343         int hit = 0;
1344
1345         pmatch->rm_so = pmatch->rm_eo = -1;
1346         if (bol < eol) {
1347                 for (p = opt->pattern_list; p; p = p->next) {
1348                         switch (p->token) {
1349                         case GREP_PATTERN: /* atom */
1350                         case GREP_PATTERN_HEAD:
1351                         case GREP_PATTERN_BODY:
1352                                 hit |= match_next_pattern(p, bol, eol, ctx,
1353                                                           pmatch, eflags);
1354                                 break;
1355                         default:
1356                                 break;
1357                         }
1358                 }
1359         }
1360         return hit;
1361 }
1362
1363 static void show_line(struct grep_opt *opt, char *bol, char *eol,
1364                       const char *name, unsigned lno, char sign)
1365 {
1366         int rest = eol - bol;
1367         const char *match_color, *line_color = NULL;
1368
1369         if (opt->file_break && opt->last_shown == 0) {
1370                 if (opt->show_hunk_mark)
1371                         opt->output(opt, "\n", 1);
1372         } else if (opt->pre_context || opt->post_context || opt->funcbody) {
1373                 if (opt->last_shown == 0) {
1374                         if (opt->show_hunk_mark) {
1375                                 output_color(opt, "--", 2, opt->color_sep);
1376                                 opt->output(opt, "\n", 1);
1377                         }
1378                 } else if (lno > opt->last_shown + 1) {
1379                         output_color(opt, "--", 2, opt->color_sep);
1380                         opt->output(opt, "\n", 1);
1381                 }
1382         }
1383         if (opt->heading && opt->last_shown == 0) {
1384                 output_color(opt, name, strlen(name), opt->color_filename);
1385                 opt->output(opt, "\n", 1);
1386         }
1387         opt->last_shown = lno;
1388
1389         if (!opt->heading && opt->pathname) {
1390                 output_color(opt, name, strlen(name), opt->color_filename);
1391                 output_sep(opt, sign);
1392         }
1393         if (opt->linenum) {
1394                 char buf[32];
1395                 xsnprintf(buf, sizeof(buf), "%d", lno);
1396                 output_color(opt, buf, strlen(buf), opt->color_lineno);
1397                 output_sep(opt, sign);
1398         }
1399         if (opt->color) {
1400                 regmatch_t match;
1401                 enum grep_context ctx = GREP_CONTEXT_BODY;
1402                 int ch = *eol;
1403                 int eflags = 0;
1404
1405                 if (sign == ':')
1406                         match_color = opt->color_match_selected;
1407                 else
1408                         match_color = opt->color_match_context;
1409                 if (sign == ':')
1410                         line_color = opt->color_selected;
1411                 else if (sign == '-')
1412                         line_color = opt->color_context;
1413                 else if (sign == '=')
1414                         line_color = opt->color_function;
1415                 *eol = '\0';
1416                 while (next_match(opt, bol, eol, ctx, &match, eflags)) {
1417                         if (match.rm_so == match.rm_eo)
1418                                 break;
1419
1420                         output_color(opt, bol, match.rm_so, line_color);
1421                         output_color(opt, bol + match.rm_so,
1422                                      match.rm_eo - match.rm_so, match_color);
1423                         bol += match.rm_eo;
1424                         rest -= match.rm_eo;
1425                         eflags = REG_NOTBOL;
1426                 }
1427                 *eol = ch;
1428         }
1429         output_color(opt, bol, rest, line_color);
1430         opt->output(opt, "\n", 1);
1431 }
1432
1433 #ifndef NO_PTHREADS
1434 int grep_use_locks;
1435
1436 /*
1437  * This lock protects access to the gitattributes machinery, which is
1438  * not thread-safe.
1439  */
1440 pthread_mutex_t grep_attr_mutex;
1441
1442 static inline void grep_attr_lock(void)
1443 {
1444         if (grep_use_locks)
1445                 pthread_mutex_lock(&grep_attr_mutex);
1446 }
1447
1448 static inline void grep_attr_unlock(void)
1449 {
1450         if (grep_use_locks)
1451                 pthread_mutex_unlock(&grep_attr_mutex);
1452 }
1453
1454 /*
1455  * Same as git_attr_mutex, but protecting the thread-unsafe object db access.
1456  */
1457 pthread_mutex_t grep_read_mutex;
1458
1459 #else
1460 #define grep_attr_lock()
1461 #define grep_attr_unlock()
1462 #endif
1463
1464 static int match_funcname(struct grep_opt *opt, struct grep_source *gs, char *bol, char *eol)
1465 {
1466         xdemitconf_t *xecfg = opt->priv;
1467         if (xecfg && !xecfg->find_func) {
1468                 grep_source_load_driver(gs);
1469                 if (gs->driver->funcname.pattern) {
1470                         const struct userdiff_funcname *pe = &gs->driver->funcname;
1471                         xdiff_set_find_func(xecfg, pe->pattern, pe->cflags);
1472                 } else {
1473                         xecfg = opt->priv = NULL;
1474                 }
1475         }
1476
1477         if (xecfg) {
1478                 char buf[1];
1479                 return xecfg->find_func(bol, eol - bol, buf, 1,
1480                                         xecfg->find_func_priv) >= 0;
1481         }
1482
1483         if (bol == eol)
1484                 return 0;
1485         if (isalpha(*bol) || *bol == '_' || *bol == '$')
1486                 return 1;
1487         return 0;
1488 }
1489
1490 static void show_funcname_line(struct grep_opt *opt, struct grep_source *gs,
1491                                char *bol, unsigned lno)
1492 {
1493         while (bol > gs->buf) {
1494                 char *eol = --bol;
1495
1496                 while (bol > gs->buf && bol[-1] != '\n')
1497                         bol--;
1498                 lno--;
1499
1500                 if (lno <= opt->last_shown)
1501                         break;
1502
1503                 if (match_funcname(opt, gs, bol, eol)) {
1504                         show_line(opt, bol, eol, gs->name, lno, '=');
1505                         break;
1506                 }
1507         }
1508 }
1509
1510 static int is_empty_line(const char *bol, const char *eol);
1511
1512 static void show_pre_context(struct grep_opt *opt, struct grep_source *gs,
1513                              char *bol, char *end, unsigned lno)
1514 {
1515         unsigned cur = lno, from = 1, funcname_lno = 0, orig_from;
1516         int funcname_needed = !!opt->funcname, comment_needed = 0;
1517
1518         if (opt->pre_context < lno)
1519                 from = lno - opt->pre_context;
1520         if (from <= opt->last_shown)
1521                 from = opt->last_shown + 1;
1522         orig_from = from;
1523         if (opt->funcbody) {
1524                 if (match_funcname(opt, gs, bol, end))
1525                         comment_needed = 1;
1526                 else
1527                         funcname_needed = 1;
1528                 from = opt->last_shown + 1;
1529         }
1530
1531         /* Rewind. */
1532         while (bol > gs->buf && cur > from) {
1533                 char *next_bol = bol;
1534                 char *eol = --bol;
1535
1536                 while (bol > gs->buf && bol[-1] != '\n')
1537                         bol--;
1538                 cur--;
1539                 if (comment_needed && (is_empty_line(bol, eol) ||
1540                                        match_funcname(opt, gs, bol, eol))) {
1541                         comment_needed = 0;
1542                         from = orig_from;
1543                         if (cur < from) {
1544                                 cur++;
1545                                 bol = next_bol;
1546                                 break;
1547                         }
1548                 }
1549                 if (funcname_needed && match_funcname(opt, gs, bol, eol)) {
1550                         funcname_lno = cur;
1551                         funcname_needed = 0;
1552                         if (opt->funcbody)
1553                                 comment_needed = 1;
1554                         else
1555                                 from = orig_from;
1556                 }
1557         }
1558
1559         /* We need to look even further back to find a function signature. */
1560         if (opt->funcname && funcname_needed)
1561                 show_funcname_line(opt, gs, bol, cur);
1562
1563         /* Back forward. */
1564         while (cur < lno) {
1565                 char *eol = bol, sign = (cur == funcname_lno) ? '=' : '-';
1566
1567                 while (*eol != '\n')
1568                         eol++;
1569                 show_line(opt, bol, eol, gs->name, cur, sign);
1570                 bol = eol + 1;
1571                 cur++;
1572         }
1573 }
1574
1575 static int should_lookahead(struct grep_opt *opt)
1576 {
1577         struct grep_pat *p;
1578
1579         if (opt->extended)
1580                 return 0; /* punt for too complex stuff */
1581         if (opt->invert)
1582                 return 0;
1583         for (p = opt->pattern_list; p; p = p->next) {
1584                 if (p->token != GREP_PATTERN)
1585                         return 0; /* punt for "header only" and stuff */
1586         }
1587         return 1;
1588 }
1589
1590 static int look_ahead(struct grep_opt *opt,
1591                       unsigned long *left_p,
1592                       unsigned *lno_p,
1593                       char **bol_p)
1594 {
1595         unsigned lno = *lno_p;
1596         char *bol = *bol_p;
1597         struct grep_pat *p;
1598         char *sp, *last_bol;
1599         regoff_t earliest = -1;
1600
1601         for (p = opt->pattern_list; p; p = p->next) {
1602                 int hit;
1603                 regmatch_t m;
1604
1605                 hit = patmatch(p, bol, bol + *left_p, &m, 0);
1606                 if (!hit || m.rm_so < 0 || m.rm_eo < 0)
1607                         continue;
1608                 if (earliest < 0 || m.rm_so < earliest)
1609                         earliest = m.rm_so;
1610         }
1611
1612         if (earliest < 0) {
1613                 *bol_p = bol + *left_p;
1614                 *left_p = 0;
1615                 return 1;
1616         }
1617         for (sp = bol + earliest; bol < sp && sp[-1] != '\n'; sp--)
1618                 ; /* find the beginning of the line */
1619         last_bol = sp;
1620
1621         for (sp = bol; sp < last_bol; sp++) {
1622                 if (*sp == '\n')
1623                         lno++;
1624         }
1625         *left_p -= last_bol - bol;
1626         *bol_p = last_bol;
1627         *lno_p = lno;
1628         return 0;
1629 }
1630
1631 static int fill_textconv_grep(struct userdiff_driver *driver,
1632                               struct grep_source *gs)
1633 {
1634         struct diff_filespec *df;
1635         char *buf;
1636         size_t size;
1637
1638         if (!driver || !driver->textconv)
1639                 return grep_source_load(gs);
1640
1641         /*
1642          * The textconv interface is intimately tied to diff_filespecs, so we
1643          * have to pretend to be one. If we could unify the grep_source
1644          * and diff_filespec structs, this mess could just go away.
1645          */
1646         df = alloc_filespec(gs->path);
1647         switch (gs->type) {
1648         case GREP_SOURCE_OID:
1649                 fill_filespec(df, gs->identifier, 1, 0100644);
1650                 break;
1651         case GREP_SOURCE_FILE:
1652                 fill_filespec(df, &null_oid, 0, 0100644);
1653                 break;
1654         default:
1655                 die("BUG: attempt to textconv something without a path?");
1656         }
1657
1658         /*
1659          * fill_textconv is not remotely thread-safe; it may load objects
1660          * behind the scenes, and it modifies the global diff tempfile
1661          * structure.
1662          */
1663         grep_read_lock();
1664         size = fill_textconv(driver, df, &buf);
1665         grep_read_unlock();
1666         free_filespec(df);
1667
1668         /*
1669          * The normal fill_textconv usage by the diff machinery would just keep
1670          * the textconv'd buf separate from the diff_filespec. But much of the
1671          * grep code passes around a grep_source and assumes that its "buf"
1672          * pointer is the beginning of the thing we are searching. So let's
1673          * install our textconv'd version into the grep_source, taking care not
1674          * to leak any existing buffer.
1675          */
1676         grep_source_clear_data(gs);
1677         gs->buf = buf;
1678         gs->size = size;
1679
1680         return 0;
1681 }
1682
1683 static int is_empty_line(const char *bol, const char *eol)
1684 {
1685         while (bol < eol && isspace(*bol))
1686                 bol++;
1687         return bol == eol;
1688 }
1689
1690 static int grep_source_1(struct grep_opt *opt, struct grep_source *gs, int collect_hits)
1691 {
1692         char *bol;
1693         char *peek_bol = NULL;
1694         unsigned long left;
1695         unsigned lno = 1;
1696         unsigned last_hit = 0;
1697         int binary_match_only = 0;
1698         unsigned count = 0;
1699         int try_lookahead = 0;
1700         int show_function = 0;
1701         struct userdiff_driver *textconv = NULL;
1702         enum grep_context ctx = GREP_CONTEXT_HEAD;
1703         xdemitconf_t xecfg;
1704
1705         if (!opt->output)
1706                 opt->output = std_output;
1707
1708         if (opt->pre_context || opt->post_context || opt->file_break ||
1709             opt->funcbody) {
1710                 /* Show hunk marks, except for the first file. */
1711                 if (opt->last_shown)
1712                         opt->show_hunk_mark = 1;
1713                 /*
1714                  * If we're using threads then we can't easily identify
1715                  * the first file.  Always put hunk marks in that case
1716                  * and skip the very first one later in work_done().
1717                  */
1718                 if (opt->output != std_output)
1719                         opt->show_hunk_mark = 1;
1720         }
1721         opt->last_shown = 0;
1722
1723         if (opt->allow_textconv) {
1724                 grep_source_load_driver(gs);
1725                 /*
1726                  * We might set up the shared textconv cache data here, which
1727                  * is not thread-safe.
1728                  */
1729                 grep_attr_lock();
1730                 textconv = userdiff_get_textconv(gs->driver);
1731                 grep_attr_unlock();
1732         }
1733
1734         /*
1735          * We know the result of a textconv is text, so we only have to care
1736          * about binary handling if we are not using it.
1737          */
1738         if (!textconv) {
1739                 switch (opt->binary) {
1740                 case GREP_BINARY_DEFAULT:
1741                         if (grep_source_is_binary(gs))
1742                                 binary_match_only = 1;
1743                         break;
1744                 case GREP_BINARY_NOMATCH:
1745                         if (grep_source_is_binary(gs))
1746                                 return 0; /* Assume unmatch */
1747                         break;
1748                 case GREP_BINARY_TEXT:
1749                         break;
1750                 default:
1751                         die("BUG: unknown binary handling mode");
1752                 }
1753         }
1754
1755         memset(&xecfg, 0, sizeof(xecfg));
1756         opt->priv = &xecfg;
1757
1758         try_lookahead = should_lookahead(opt);
1759
1760         if (fill_textconv_grep(textconv, gs) < 0)
1761                 return 0;
1762
1763         bol = gs->buf;
1764         left = gs->size;
1765         while (left) {
1766                 char *eol, ch;
1767                 int hit;
1768
1769                 /*
1770                  * look_ahead() skips quickly to the line that possibly
1771                  * has the next hit; don't call it if we need to do
1772                  * something more than just skipping the current line
1773                  * in response to an unmatch for the current line.  E.g.
1774                  * inside a post-context window, we will show the current
1775                  * line as a context around the previous hit when it
1776                  * doesn't hit.
1777                  */
1778                 if (try_lookahead
1779                     && !(last_hit
1780                          && (show_function ||
1781                              lno <= last_hit + opt->post_context))
1782                     && look_ahead(opt, &left, &lno, &bol))
1783                         break;
1784                 eol = end_of_line(bol, &left);
1785                 ch = *eol;
1786                 *eol = 0;
1787
1788                 if ((ctx == GREP_CONTEXT_HEAD) && (eol == bol))
1789                         ctx = GREP_CONTEXT_BODY;
1790
1791                 hit = match_line(opt, bol, eol, ctx, collect_hits);
1792                 *eol = ch;
1793
1794                 if (collect_hits)
1795                         goto next_line;
1796
1797                 /* "grep -v -e foo -e bla" should list lines
1798                  * that do not have either, so inversion should
1799                  * be done outside.
1800                  */
1801                 if (opt->invert)
1802                         hit = !hit;
1803                 if (opt->unmatch_name_only) {
1804                         if (hit)
1805                                 return 0;
1806                         goto next_line;
1807                 }
1808                 if (hit) {
1809                         count++;
1810                         if (opt->status_only)
1811                                 return 1;
1812                         if (opt->name_only) {
1813                                 show_name(opt, gs->name);
1814                                 return 1;
1815                         }
1816                         if (opt->count)
1817                                 goto next_line;
1818                         if (binary_match_only) {
1819                                 opt->output(opt, "Binary file ", 12);
1820                                 output_color(opt, gs->name, strlen(gs->name),
1821                                              opt->color_filename);
1822                                 opt->output(opt, " matches\n", 9);
1823                                 return 1;
1824                         }
1825                         /* Hit at this line.  If we haven't shown the
1826                          * pre-context lines, we would need to show them.
1827                          */
1828                         if (opt->pre_context || opt->funcbody)
1829                                 show_pre_context(opt, gs, bol, eol, lno);
1830                         else if (opt->funcname)
1831                                 show_funcname_line(opt, gs, bol, lno);
1832                         show_line(opt, bol, eol, gs->name, lno, ':');
1833                         last_hit = lno;
1834                         if (opt->funcbody)
1835                                 show_function = 1;
1836                         goto next_line;
1837                 }
1838                 if (show_function && (!peek_bol || peek_bol < bol)) {
1839                         unsigned long peek_left = left;
1840                         char *peek_eol = eol;
1841
1842                         /*
1843                          * Trailing empty lines are not interesting.
1844                          * Peek past them to see if they belong to the
1845                          * body of the current function.
1846                          */
1847                         peek_bol = bol;
1848                         while (is_empty_line(peek_bol, peek_eol)) {
1849                                 peek_bol = peek_eol + 1;
1850                                 peek_eol = end_of_line(peek_bol, &peek_left);
1851                         }
1852
1853                         if (match_funcname(opt, gs, peek_bol, peek_eol))
1854                                 show_function = 0;
1855                 }
1856                 if (show_function ||
1857                     (last_hit && lno <= last_hit + opt->post_context)) {
1858                         /* If the last hit is within the post context,
1859                          * we need to show this line.
1860                          */
1861                         show_line(opt, bol, eol, gs->name, lno, '-');
1862                 }
1863
1864         next_line:
1865                 bol = eol + 1;
1866                 if (!left)
1867                         break;
1868                 left--;
1869                 lno++;
1870         }
1871
1872         if (collect_hits)
1873                 return 0;
1874
1875         if (opt->status_only)
1876                 return opt->unmatch_name_only;
1877         if (opt->unmatch_name_only) {
1878                 /* We did not see any hit, so we want to show this */
1879                 show_name(opt, gs->name);
1880                 return 1;
1881         }
1882
1883         xdiff_clear_find_func(&xecfg);
1884         opt->priv = NULL;
1885
1886         /* NEEDSWORK:
1887          * The real "grep -c foo *.c" gives many "bar.c:0" lines,
1888          * which feels mostly useless but sometimes useful.  Maybe
1889          * make it another option?  For now suppress them.
1890          */
1891         if (opt->count && count) {
1892                 char buf[32];
1893                 if (opt->pathname) {
1894                         output_color(opt, gs->name, strlen(gs->name),
1895                                      opt->color_filename);
1896                         output_sep(opt, ':');
1897                 }
1898                 xsnprintf(buf, sizeof(buf), "%u\n", count);
1899                 opt->output(opt, buf, strlen(buf));
1900                 return 1;
1901         }
1902         return !!last_hit;
1903 }
1904
1905 static void clr_hit_marker(struct grep_expr *x)
1906 {
1907         /* All-hit markers are meaningful only at the very top level
1908          * OR node.
1909          */
1910         while (1) {
1911                 x->hit = 0;
1912                 if (x->node != GREP_NODE_OR)
1913                         return;
1914                 x->u.binary.left->hit = 0;
1915                 x = x->u.binary.right;
1916         }
1917 }
1918
1919 static int chk_hit_marker(struct grep_expr *x)
1920 {
1921         /* Top level nodes have hit markers.  See if they all are hits */
1922         while (1) {
1923                 if (x->node != GREP_NODE_OR)
1924                         return x->hit;
1925                 if (!x->u.binary.left->hit)
1926                         return 0;
1927                 x = x->u.binary.right;
1928         }
1929 }
1930
1931 int grep_source(struct grep_opt *opt, struct grep_source *gs)
1932 {
1933         /*
1934          * we do not have to do the two-pass grep when we do not check
1935          * buffer-wide "all-match".
1936          */
1937         if (!opt->all_match)
1938                 return grep_source_1(opt, gs, 0);
1939
1940         /* Otherwise the toplevel "or" terms hit a bit differently.
1941          * We first clear hit markers from them.
1942          */
1943         clr_hit_marker(opt->pattern_expression);
1944         grep_source_1(opt, gs, 1);
1945
1946         if (!chk_hit_marker(opt->pattern_expression))
1947                 return 0;
1948
1949         return grep_source_1(opt, gs, 0);
1950 }
1951
1952 int grep_buffer(struct grep_opt *opt, char *buf, unsigned long size)
1953 {
1954         struct grep_source gs;
1955         int r;
1956
1957         grep_source_init(&gs, GREP_SOURCE_BUF, NULL, NULL, NULL);
1958         gs.buf = buf;
1959         gs.size = size;
1960
1961         r = grep_source(opt, &gs);
1962
1963         grep_source_clear(&gs);
1964         return r;
1965 }
1966
1967 void grep_source_init(struct grep_source *gs, enum grep_source_type type,
1968                       const char *name, const char *path,
1969                       const void *identifier)
1970 {
1971         gs->type = type;
1972         gs->name = xstrdup_or_null(name);
1973         gs->path = xstrdup_or_null(path);
1974         gs->buf = NULL;
1975         gs->size = 0;
1976         gs->driver = NULL;
1977
1978         switch (type) {
1979         case GREP_SOURCE_FILE:
1980                 gs->identifier = xstrdup(identifier);
1981                 break;
1982         case GREP_SOURCE_OID:
1983                 gs->identifier = oiddup(identifier);
1984                 break;
1985         case GREP_SOURCE_BUF:
1986                 gs->identifier = NULL;
1987                 break;
1988         }
1989 }
1990
1991 void grep_source_clear(struct grep_source *gs)
1992 {
1993         FREE_AND_NULL(gs->name);
1994         FREE_AND_NULL(gs->path);
1995         FREE_AND_NULL(gs->identifier);
1996         grep_source_clear_data(gs);
1997 }
1998
1999 void grep_source_clear_data(struct grep_source *gs)
2000 {
2001         switch (gs->type) {
2002         case GREP_SOURCE_FILE:
2003         case GREP_SOURCE_OID:
2004                 FREE_AND_NULL(gs->buf);
2005                 gs->size = 0;
2006                 break;
2007         case GREP_SOURCE_BUF:
2008                 /* leave user-provided buf intact */
2009                 break;
2010         }
2011 }
2012
2013 static int grep_source_load_oid(struct grep_source *gs)
2014 {
2015         enum object_type type;
2016
2017         grep_read_lock();
2018         gs->buf = read_sha1_file(gs->identifier, &type, &gs->size);
2019         grep_read_unlock();
2020
2021         if (!gs->buf)
2022                 return error(_("'%s': unable to read %s"),
2023                              gs->name,
2024                              oid_to_hex(gs->identifier));
2025         return 0;
2026 }
2027
2028 static int grep_source_load_file(struct grep_source *gs)
2029 {
2030         const char *filename = gs->identifier;
2031         struct stat st;
2032         char *data;
2033         size_t size;
2034         int i;
2035
2036         if (lstat(filename, &st) < 0) {
2037         err_ret:
2038                 if (errno != ENOENT)
2039                         error_errno(_("failed to stat '%s'"), filename);
2040                 return -1;
2041         }
2042         if (!S_ISREG(st.st_mode))
2043                 return -1;
2044         size = xsize_t(st.st_size);
2045         i = open(filename, O_RDONLY);
2046         if (i < 0)
2047                 goto err_ret;
2048         data = xmallocz(size);
2049         if (st.st_size != read_in_full(i, data, size)) {
2050                 error_errno(_("'%s': short read"), filename);
2051                 close(i);
2052                 free(data);
2053                 return -1;
2054         }
2055         close(i);
2056
2057         gs->buf = data;
2058         gs->size = size;
2059         return 0;
2060 }
2061
2062 static int grep_source_load(struct grep_source *gs)
2063 {
2064         if (gs->buf)
2065                 return 0;
2066
2067         switch (gs->type) {
2068         case GREP_SOURCE_FILE:
2069                 return grep_source_load_file(gs);
2070         case GREP_SOURCE_OID:
2071                 return grep_source_load_oid(gs);
2072         case GREP_SOURCE_BUF:
2073                 return gs->buf ? 0 : -1;
2074         }
2075         die("BUG: invalid grep_source type to load");
2076 }
2077
2078 void grep_source_load_driver(struct grep_source *gs)
2079 {
2080         if (gs->driver)
2081                 return;
2082
2083         grep_attr_lock();
2084         if (gs->path)
2085                 gs->driver = userdiff_find_by_path(gs->path);
2086         if (!gs->driver)
2087                 gs->driver = userdiff_find_by_name("default");
2088         grep_attr_unlock();
2089 }
2090
2091 static int grep_source_is_binary(struct grep_source *gs)
2092 {
2093         grep_source_load_driver(gs);
2094         if (gs->driver->binary != -1)
2095                 return gs->driver->binary;
2096
2097         if (!grep_source_load(gs))
2098                 return buffer_is_binary(gs->buf, gs->size);
2099
2100         return 0;
2101 }