grep.c

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