findutils/grep.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Mini grep implementation for busybox using libc regex.
   4  *
   5  * Copyright (C) 1999,2000,2001 by Lineo, inc. and Mark Whitley
   6  * Copyright (C) 1999,2000,2001 by Mark Whitley <markw@codepoet.org>
   7  *
   8  * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
   9  */
  10 /* BB_AUDIT SUSv3 defects - unsupported option -x "match whole line only". */
  11 /* BB_AUDIT GNU defects - always acts as -a.  */
  12 /* http://www.opengroup.org/onlinepubs/007904975/utilities/grep.html */
  13 /*
  14  * 2004,2006 (C) Vladimir Oleynik <dzo@simtreas.ru> -
  15  * correction "-e pattern1 -e pattern2" logic and more optimizations.
  16  * precompiled regex
  17  */
  18 /*
  19  * (C) 2006 Jac Goudsmit added -o option
  20  */
  21
  22 #include "libbb.h"
  23 #include "xregex.h"
  24
  25 /* options */
  26 #define OPTSTR_GREP \
  27         "lnqvscFiHhe:f:Lorm:w" \
  28         IF_FEATURE_GREP_CONTEXT("A:B:C:") \
  29         IF_FEATURE_GREP_EGREP_ALIAS("E") \
  30         IF_EXTRA_COMPAT("z") \
  31         "aI"
  32
  33 /* ignored: -a "assume all files to be text" */
  34 /* ignored: -I "assume binary files have no matches" */
  35
  36 enum {
  37         OPTBIT_l, /* list matched file names only */
  38         OPTBIT_n, /* print line# */
  39         OPTBIT_q, /* quiet - exit(EXIT_SUCCESS) of first match */
  40         OPTBIT_v, /* invert the match, to select non-matching lines */
  41         OPTBIT_s, /* suppress errors about file open errors */
  42         OPTBIT_c, /* count matches per file (suppresses normal output) */
  43         OPTBIT_F, /* literal match */
  44         OPTBIT_i, /* case-insensitive */
  45         OPTBIT_H, /* force filename display */
  46         OPTBIT_h, /* inhibit filename display */
  47         OPTBIT_e, /* -e PATTERN */
  48         OPTBIT_f, /* -f FILE_WITH_PATTERNS */
  49         OPTBIT_L, /* list unmatched file names only */
  50         OPTBIT_o, /* show only matching parts of lines */
  51         OPTBIT_r, /* recurse dirs */
  52         OPTBIT_m, /* -m MAX_MATCHES */
  53         OPTBIT_w, /* -w whole word match */
  54         IF_FEATURE_GREP_CONTEXT(    OPTBIT_A ,) /* -A NUM: after-match context */
  55         IF_FEATURE_GREP_CONTEXT(    OPTBIT_B ,) /* -B NUM: before-match context */
  56         IF_FEATURE_GREP_CONTEXT(    OPTBIT_C ,) /* -C NUM: -A and -B combined */
  57         IF_FEATURE_GREP_EGREP_ALIAS(OPTBIT_E ,) /* extended regexp */
  58         IF_EXTRA_COMPAT(            OPTBIT_z ,) /* input is NUL terminated */
  59         OPT_l = 1 << OPTBIT_l,
  60         OPT_n = 1 << OPTBIT_n,
  61         OPT_q = 1 << OPTBIT_q,
  62         OPT_v = 1 << OPTBIT_v,
  63         OPT_s = 1 << OPTBIT_s,
  64         OPT_c = 1 << OPTBIT_c,
  65         OPT_F = 1 << OPTBIT_F,
  66         OPT_i = 1 << OPTBIT_i,
  67         OPT_H = 1 << OPTBIT_H,
  68         OPT_h = 1 << OPTBIT_h,
  69         OPT_e = 1 << OPTBIT_e,
  70         OPT_f = 1 << OPTBIT_f,
  71         OPT_L = 1 << OPTBIT_L,
  72         OPT_o = 1 << OPTBIT_o,
  73         OPT_r = 1 << OPTBIT_r,
  74         OPT_m = 1 << OPTBIT_m,
  75         OPT_w = 1 << OPTBIT_w,
  76         OPT_A = IF_FEATURE_GREP_CONTEXT(    (1 << OPTBIT_A)) + 0,
  77         OPT_B = IF_FEATURE_GREP_CONTEXT(    (1 << OPTBIT_B)) + 0,
  78         OPT_C = IF_FEATURE_GREP_CONTEXT(    (1 << OPTBIT_C)) + 0,
  79         OPT_E = IF_FEATURE_GREP_EGREP_ALIAS((1 << OPTBIT_E)) + 0,
  80         OPT_z = IF_EXTRA_COMPAT(            (1 << OPTBIT_z)) + 0,
  81 };
  82
  83 #define PRINT_FILES_WITH_MATCHES    (option_mask32 & OPT_l)
  84 #define PRINT_LINE_NUM              (option_mask32 & OPT_n)
  85 #define BE_QUIET                    (option_mask32 & OPT_q)
  86 #define SUPPRESS_ERR_MSGS           (option_mask32 & OPT_s)
  87 #define PRINT_MATCH_COUNTS          (option_mask32 & OPT_c)
  88 #define FGREP_FLAG                  (option_mask32 & OPT_F)
  89 #define PRINT_FILES_WITHOUT_MATCHES (option_mask32 & OPT_L)
  90 #define NUL_DELIMITED               (option_mask32 & OPT_z)
  91
  92 struct globals {
  93         int max_matches;
  94 #if !ENABLE_EXTRA_COMPAT
  95         int reflags;
  96 #else
  97         RE_TRANSLATE_TYPE case_fold; /* RE_TRANSLATE_TYPE is [[un]signed] char* */
  98 #endif
  99         smalluint invert_search;
 100         smalluint print_filename;
 101         smalluint open_errors;
 102 #if ENABLE_FEATURE_GREP_CONTEXT
 103         smalluint did_print_line;
 104         int lines_before;
 105         int lines_after;
 106         char **before_buf;
 107         IF_EXTRA_COMPAT(size_t *before_buf_size;)
 108         int last_line_printed;
 109 #endif
 110         /* globals used internally */
 111         llist_t *pattern_head;   /* growable list of patterns to match */
 112         const char *cur_file;    /* the current file we are reading */
 113 } FIX_ALIASING;
 114 #define G (*(struct globals*)&bb_common_bufsiz1)
 115 #define INIT_G() do { \
 116         struct G_sizecheck { \
 117                 char G_sizecheck[sizeof(G) > COMMON_BUFSIZE ? -1 : 1]; \
 118         }; \
 119 } while (0)
 120 #define max_matches       (G.max_matches         )
 121 #if !ENABLE_EXTRA_COMPAT
 122 # define reflags          (G.reflags             )
 123 #else
 124 # define case_fold        (G.case_fold           )
 125 /* http://www.delorie.com/gnu/docs/regex/regex_46.html */
 126 # define reflags           re_syntax_options
 127 # undef REG_NOSUB
 128 # undef REG_EXTENDED
 129 # undef REG_ICASE
 130 # define REG_NOSUB    bug:is:here /* should not be used */
 131 /* Just RE_SYNTAX_EGREP is not enough, need to enable {n[,[m]]} too */
 132 # define REG_EXTENDED (RE_SYNTAX_EGREP | RE_INTERVALS | RE_NO_BK_BRACES)
 133 # define REG_ICASE    bug:is:here /* should not be used */
 134 #endif
 135 #define invert_search     (G.invert_search       )
 136 #define print_filename    (G.print_filename      )
 137 #define open_errors       (G.open_errors         )
 138 #define did_print_line    (G.did_print_line      )
 139 #define lines_before      (G.lines_before        )
 140 #define lines_after       (G.lines_after         )
 141 #define before_buf        (G.before_buf          )
 142 #define before_buf_size   (G.before_buf_size     )
 143 #define last_line_printed (G.last_line_printed   )
 144 #define pattern_head      (G.pattern_head        )
 145 #define cur_file          (G.cur_file            )
 146
 147
 148 typedef struct grep_list_data_t {
 149         char *pattern;
 150 /* for GNU regex, matched_range must be persistent across grep_file() calls */
 151 #if !ENABLE_EXTRA_COMPAT
 152         regex_t compiled_regex;
 153         regmatch_t matched_range;
 154 #else
 155         struct re_pattern_buffer compiled_regex;
 156         struct re_registers matched_range;
 157 #endif
 158 #define ALLOCATED 1
 159 #define COMPILED 2
 160         int flg_mem_alocated_compiled;
 161 } grep_list_data_t;
 162
 163 #if !ENABLE_EXTRA_COMPAT
 164 #define print_line(line, line_len, linenum, decoration) \
 165         print_line(line, linenum, decoration)
 166 #endif
 167 static void print_line(const char *line, size_t line_len, int linenum, char decoration)
 168 {
 169 #if ENABLE_FEATURE_GREP_CONTEXT
 170         /* Happens when we go to next file, immediately hit match
 171          * and try to print prev context... from prev file! Don't do it */
 172         if (linenum < 1)
 173                 return;
 174         /* possibly print the little '--' separator */
 175         if ((lines_before || lines_after) && did_print_line
 176          && last_line_printed != linenum - 1
 177         ) {
 178                 puts("--");
 179         }
 180         /* guard against printing "--" before first line of first file */
 181         did_print_line = 1;
 182         last_line_printed = linenum;
 183 #endif
 184         if (print_filename)
 185                 printf("%s%c", cur_file, decoration);
 186         if (PRINT_LINE_NUM)
 187                 printf("%i%c", linenum, decoration);
 188         /* Emulate weird GNU grep behavior with -ov */
 189         if ((option_mask32 & (OPT_v|OPT_o)) != (OPT_v|OPT_o)) {
 190 #if !ENABLE_EXTRA_COMPAT
 191                 puts(line);
 192 #else
 193                 fwrite(line, 1, line_len, stdout);
 194                 putchar(NUL_DELIMITED ? '\0' : '\n');
 195 #endif
 196         }
 197 }
 198
 199 #if ENABLE_EXTRA_COMPAT
 200 /* Unlike getline, this one removes trailing '\n' */
 201 static ssize_t FAST_FUNC bb_getline(char **line_ptr, size_t *line_alloc_len, FILE *file)
 202 {
 203         ssize_t res_sz;
 204         char *line;
 205         int delim = (NUL_DELIMITED ? '\0' : '\n');
 206
 207         res_sz = getdelim(line_ptr, line_alloc_len, delim, file);
 208         line = *line_ptr;
 209
 210         if (res_sz > 0) {
 211                 if (line[res_sz - 1] == delim)
 212                         line[--res_sz] = '\0';
 213         } else {
 214                 free(line); /* uclibc allocates a buffer even on EOF. WTF? */
 215         }
 216         return res_sz;
 217 }
 218 #endif
 219
 220 static int grep_file(FILE *file)
 221 {
 222         smalluint found;
 223         int linenum = 0;
 224         int nmatches = 0;
 225 #if !ENABLE_EXTRA_COMPAT
 226         char *line;
 227 #else
 228         char *line = NULL;
 229         ssize_t line_len;
 230         size_t line_alloc_len;
 231 # define rm_so start[0]
 232 # define rm_eo end[0]
 233 #endif
 234 #if ENABLE_FEATURE_GREP_CONTEXT
 235         int print_n_lines_after = 0;
 236         int curpos = 0; /* track where we are in the circular 'before' buffer */
 237         int idx = 0; /* used for iteration through the circular buffer */
 238 #else
 239         enum { print_n_lines_after = 0 };
 240 #endif
 241
 242         while (
 243 #if !ENABLE_EXTRA_COMPAT
 244                 (line = xmalloc_fgetline(file)) != NULL
 245 #else
 246                 (line_len = bb_getline(&line, &line_alloc_len, file)) >= 0
 247 #endif
 248         ) {
 249                 llist_t *pattern_ptr = pattern_head;
 250                 grep_list_data_t *gl = gl; /* for gcc */
 251
 252                 linenum++;
 253                 found = 0;
 254                 while (pattern_ptr) {
 255                         gl = (grep_list_data_t *)pattern_ptr->data;
 256                         if (FGREP_FLAG) {
 257                                 found |= (strstr(line, gl->pattern) != NULL);
 258                         } else {
 259                                 if (!(gl->flg_mem_alocated_compiled & COMPILED)) {
 260                                         gl->flg_mem_alocated_compiled |= COMPILED;
 261 #if !ENABLE_EXTRA_COMPAT
 262                                         xregcomp(&gl->compiled_regex, gl->pattern, reflags);
 263 #else
 264                                         memset(&gl->compiled_regex, 0, sizeof(gl->compiled_regex));
 265                                         gl->compiled_regex.translate = case_fold; /* for -i */
 266                                         if (re_compile_pattern(gl->pattern, strlen(gl->pattern), &gl->compiled_regex))
 267                                                 bb_error_msg_and_die("bad regex '%s'", gl->pattern);
 268 #endif
 269                                 }
 270 #if !ENABLE_EXTRA_COMPAT
 271                                 gl->matched_range.rm_so = 0;
 272                                 gl->matched_range.rm_eo = 0;
 273 #endif
 274                                 if (
 275 #if !ENABLE_EXTRA_COMPAT
 276                                         regexec(&gl->compiled_regex, line, 1, &gl->matched_range, 0) == 0
 277 #else
 278                                         re_search(&gl->compiled_regex, line, line_len,
 279                                                         /*start:*/ 0, /*range:*/ line_len,
 280                                                         &gl->matched_range) >= 0
 281 #endif
 282                                 ) {
 283                                         if (!(option_mask32 & OPT_w))
 284                                                 found = 1;
 285                                         else {
 286                                                 char c = ' ';
 287                                                 if (gl->matched_range.rm_so)
 288                                                         c = line[gl->matched_range.rm_so - 1];
 289                                                 if (!isalnum(c) && c != '_') {
 290                                                         c = line[gl->matched_range.rm_eo];
 291                                                         if (!c || (!isalnum(c) && c != '_'))
 292                                                                 found = 1;
 293                                                 }
 294                                         }
 295                                 }
 296                         }
 297                         /* If it's non-inverted search, we can stop
 298                          * at first match */
 299                         if (found && !invert_search)
 300                                 goto do_found;
 301                         pattern_ptr = pattern_ptr->link;
 302                 } /* while (pattern_ptr) */
 303
 304                 if (found ^ invert_search) {
 305  do_found:
 306                         /* keep track of matches */
 307                         nmatches++;
 308
 309                         /* quiet/print (non)matching file names only? */
 310                         if (option_mask32 & (OPT_q|OPT_l|OPT_L)) {
 311                                 free(line); /* we don't need line anymore */
 312                                 if (BE_QUIET) {
 313                                         /* manpage says about -q:
 314                                          * "exit immediately with zero status
 315                                          * if any match is found,
 316                                          * even if errors were detected" */
 317                                         exit(EXIT_SUCCESS);
 318                                 }
 319                                 /* if we're just printing filenames, we stop after the first match */
 320                                 if (PRINT_FILES_WITH_MATCHES) {
 321                                         puts(cur_file);
 322                                         /* fall through to "return 1" */
 323                                 }
 324                                 /* OPT_L aka PRINT_FILES_WITHOUT_MATCHES: return early */
 325                                 return 1; /* one match */
 326                         }
 327
 328 #if ENABLE_FEATURE_GREP_CONTEXT
 329                         /* Were we printing context and saw next (unwanted) match? */
 330                         if ((option_mask32 & OPT_m) && nmatches > max_matches)
 331                                 break;
 332 #endif
 333
 334                         /* print the matched line */
 335                         if (PRINT_MATCH_COUNTS == 0) {
 336 #if ENABLE_FEATURE_GREP_CONTEXT
 337                                 int prevpos = (curpos == 0) ? lines_before - 1 : curpos - 1;
 338
 339                                 /* if we were told to print 'before' lines and there is at least
 340                                  * one line in the circular buffer, print them */
 341                                 if (lines_before && before_buf[prevpos] != NULL) {
 342                                         int first_buf_entry_line_num = linenum - lines_before;
 343
 344                                         /* advance to the first entry in the circular buffer, and
 345                                          * figure out the line number is of the first line in the
 346                                          * buffer */
 347                                         idx = curpos;
 348                                         while (before_buf[idx] == NULL) {
 349                                                 idx = (idx + 1) % lines_before;
 350                                                 first_buf_entry_line_num++;
 351                                         }
 352
 353                                         /* now print each line in the buffer, clearing them as we go */
 354                                         while (before_buf[idx] != NULL) {
 355                                                 print_line(before_buf[idx], before_buf_size[idx], first_buf_entry_line_num, '-');
 356                                                 free(before_buf[idx]);
 357                                                 before_buf[idx] = NULL;
 358                                                 idx = (idx + 1) % lines_before;
 359                                                 first_buf_entry_line_num++;
 360                                         }
 361                                 }
 362
 363                                 /* make a note that we need to print 'after' lines */
 364                                 print_n_lines_after = lines_after;
 365 #endif
 366                                 if (option_mask32 & OPT_o) {
 367                                         if (FGREP_FLAG) {
 368                                                 /* -Fo just prints the pattern
 369                                                  * (unless -v: -Fov doesnt print anything at all) */
 370                                                 if (found)
 371                                                         print_line(gl->pattern, strlen(gl->pattern), linenum, ':');
 372                                         } else while (1) {
 373                                                 unsigned end = gl->matched_range.rm_eo;
 374                                                 char old = line[end];
 375                                                 line[end] = '\0';
 376                                                 print_line(line + gl->matched_range.rm_so,
 377                                                                 end - gl->matched_range.rm_so,
 378                                                                 linenum, ':');
 379                                                 if (old == '\0')
 380                                                         break;
 381                                                 line[end] = old;
 382 #if !ENABLE_EXTRA_COMPAT
 383                                                 if (regexec(&gl->compiled_regex, line + end,
 384                                                                 1, &gl->matched_range, REG_NOTBOL) != 0)
 385                                                         break;
 386                                                 gl->matched_range.rm_so += end;
 387                                                 gl->matched_range.rm_eo += end;
 388 #else
 389                                                 if (re_search(&gl->compiled_regex, line, line_len,
 390                                                                 end, line_len - end,
 391                                                                 &gl->matched_range) < 0)
 392                                                         break;
 393 #endif
 394                                         }
 395                                 } else {
 396                                         print_line(line, line_len, linenum, ':');
 397                                 }
 398                         }
 399                 }
 400 #if ENABLE_FEATURE_GREP_CONTEXT
 401                 else { /* no match */
 402                         /* if we need to print some context lines after the last match, do so */
 403                         if (print_n_lines_after) {
 404                                 print_line(line, strlen(line), linenum, '-');
 405                                 print_n_lines_after--;
 406                         } else if (lines_before) {
 407                                 /* Add the line to the circular 'before' buffer */
 408                                 free(before_buf[curpos]);
 409                                 before_buf[curpos] = line;
 410                                 IF_EXTRA_COMPAT(before_buf_size[curpos] = line_len;)
 411                                 curpos = (curpos + 1) % lines_before;
 412                                 /* avoid free(line) - we took the line */
 413                                 line = NULL;
 414                         }
 415                 }
 416
 417 #endif /* ENABLE_FEATURE_GREP_CONTEXT */
 418 #if !ENABLE_EXTRA_COMPAT
 419                 free(line);
 420 #endif
 421                 /* Did we print all context after last requested match? */
 422                 if ((option_mask32 & OPT_m)
 423                  && !print_n_lines_after
 424                  && nmatches == max_matches
 425                 ) {
 426                         break;
 427                 }
 428         } /* while (read line) */
 429
 430         /* special-case file post-processing for options where we don't print line
 431          * matches, just filenames and possibly match counts */
 432
 433         /* grep -c: print [filename:]count, even if count is zero */
 434         if (PRINT_MATCH_COUNTS) {
 435                 if (print_filename)
 436                         printf("%s:", cur_file);
 437                 printf("%d\n", nmatches);
 438         }
 439
 440         /* grep -L: print just the filename */
 441         if (PRINT_FILES_WITHOUT_MATCHES) {
 442                 /* nmatches is zero, no need to check it:
 443                  * we return 1 early if we detected a match
 444                  * and PRINT_FILES_WITHOUT_MATCHES is set */
 445                 puts(cur_file);
 446         }
 447
 448         return nmatches;
 449 }
 450
 451 #if ENABLE_FEATURE_CLEAN_UP
 452 #define new_grep_list_data(p, m) add_grep_list_data(p, m)
 453 static char *add_grep_list_data(char *pattern, int flg_used_mem)
 454 #else
 455 #define new_grep_list_data(p, m) add_grep_list_data(p)
 456 static char *add_grep_list_data(char *pattern)
 457 #endif
 458 {
 459         grep_list_data_t *gl = xzalloc(sizeof(*gl));
 460         gl->pattern = pattern;
 461 #if ENABLE_FEATURE_CLEAN_UP
 462         gl->flg_mem_alocated_compiled = flg_used_mem;
 463 #else
 464         /*gl->flg_mem_alocated_compiled = 0;*/
 465 #endif
 466         return (char *)gl;
 467 }
 468
 469 static void load_regexes_from_file(llist_t *fopt)
 470 {
 471         char *line;
 472         FILE *f;
 473
 474         while (fopt) {
 475                 llist_t *cur = fopt;
 476                 char *ffile = cur->data;
 477
 478                 fopt = cur->link;
 479                 free(cur);
 480                 f = xfopen_stdin(ffile);
 481                 while ((line = xmalloc_fgetline(f)) != NULL) {
 482                         llist_add_to(&pattern_head,
 483                                 new_grep_list_data(line, ALLOCATED));
 484                 }
 485         }
 486 }
 487
 488 static int FAST_FUNC file_action_grep(const char *filename,
 489                         struct stat *statbuf UNUSED_PARAM,
 490                         void* matched,
 491                         int depth UNUSED_PARAM)
 492 {
 493         FILE *file = fopen_for_read(filename);
 494         if (file == NULL) {
 495                 if (!SUPPRESS_ERR_MSGS)
 496                         bb_simple_perror_msg(filename);
 497                 open_errors = 1;
 498                 return 0;
 499         }
 500         cur_file = filename;
 501         *(int*)matched += grep_file(file);
 502         fclose(file);
 503         return 1;
 504 }
 505
 506 static int grep_dir(const char *dir)
 507 {
 508         int matched = 0;
 509         recursive_action(dir,
 510                 /* recurse=yes */ ACTION_RECURSE |
 511                 /* followLinks=no */
 512                 /* depthFirst=yes */ ACTION_DEPTHFIRST,
 513                 /* fileAction= */ file_action_grep,
 514                 /* dirAction= */ NULL,
 515                 /* userData= */ &matched,
 516                 /* depth= */ 0);
 517         return matched;
 518 }
 519
 520 int grep_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 521 int grep_main(int argc UNUSED_PARAM, char **argv)
 522 {
 523         FILE *file;
 524         int matched;
 525         llist_t *fopt = NULL;
 526
 527         /* do normal option parsing */
 528 #if ENABLE_FEATURE_GREP_CONTEXT
 529         int Copt;
 530
 531         /* -H unsets -h; -C unsets -A,-B; -e,-f are lists;
 532          * -m,-A,-B,-C have numeric param */
 533         opt_complementary = "H-h:C-AB:e::f::m+:A+:B+:C+";
 534         getopt32(argv,
 535                 OPTSTR_GREP,
 536                 &pattern_head, &fopt, &max_matches,
 537                 &lines_after, &lines_before, &Copt);
 538
 539         if (option_mask32 & OPT_C) {
 540                 /* -C unsets prev -A and -B, but following -A or -B
 541                    may override it */
 542                 if (!(option_mask32 & OPT_A)) /* not overridden */
 543                         lines_after = Copt;
 544                 if (!(option_mask32 & OPT_B)) /* not overridden */
 545                         lines_before = Copt;
 546         }
 547         /* sanity checks */
 548         if (option_mask32 & (OPT_c|OPT_q|OPT_l|OPT_L)) {
 549                 option_mask32 &= ~OPT_n;
 550                 lines_before = 0;
 551                 lines_after = 0;
 552         } else if (lines_before > 0) {
 553                 before_buf = xzalloc(lines_before * sizeof(before_buf[0]));
 554                 IF_EXTRA_COMPAT(before_buf_size = xzalloc(lines_before * sizeof(before_buf_size[0]));)
 555         }
 556 #else
 557         /* with auto sanity checks */
 558         /* -H unsets -h; -c,-q or -l unset -n; -e,-f are lists; -m N */
 559         opt_complementary = "H-h:c-n:q-n:l-n:e::f::m+";
 560         getopt32(argv, OPTSTR_GREP,
 561                 &pattern_head, &fopt, &max_matches);
 562 #endif
 563         invert_search = ((option_mask32 & OPT_v) != 0); /* 0 | 1 */
 564
 565         if (pattern_head != NULL) {
 566                 /* convert char **argv to grep_list_data_t */
 567                 llist_t *cur;
 568
 569                 for (cur = pattern_head; cur; cur = cur->link)
 570                         cur->data = new_grep_list_data(cur->data, 0);
 571         }
 572         if (option_mask32 & OPT_f)
 573                 load_regexes_from_file(fopt);
 574
 575         if (ENABLE_FEATURE_GREP_FGREP_ALIAS && applet_name[0] == 'f')
 576                 option_mask32 |= OPT_F;
 577
 578 #if !ENABLE_EXTRA_COMPAT
 579         if (!(option_mask32 & (OPT_o | OPT_w)))
 580                 reflags = REG_NOSUB;
 581 #endif
 582
 583         if (ENABLE_FEATURE_GREP_EGREP_ALIAS
 584          && (applet_name[0] == 'e' || (option_mask32 & OPT_E))
 585         ) {
 586                 reflags |= REG_EXTENDED;
 587         }
 588 #if ENABLE_EXTRA_COMPAT
 589         else {
 590                 reflags = RE_SYNTAX_GREP;
 591         }
 592 #endif
 593
 594         if (option_mask32 & OPT_i) {
 595 #if !ENABLE_EXTRA_COMPAT
 596                 reflags |= REG_ICASE;
 597 #else
 598                 int i;
 599                 case_fold = xmalloc(256);
 600                 for (i = 0; i < 256; i++)
 601                         case_fold[i] = (unsigned char)i;
 602                 for (i = 'a'; i <= 'z'; i++)
 603                         case_fold[i] = (unsigned char)(i - ('a' - 'A'));
 604 #endif
 605         }
 606
 607         argv += optind;
 608
 609         /* if we didn't get a pattern from -e and no command file was specified,
 610          * first parameter should be the pattern. no pattern, no worky */
 611         if (pattern_head == NULL) {
 612                 char *pattern;
 613                 if (*argv == NULL)
 614                         bb_show_usage();
 615                 pattern = new_grep_list_data(*argv++, 0);
 616                 llist_add_to(&pattern_head, pattern);
 617         }
 618
 619         /* argv[0..(argc-1)] should be names of file to grep through. If
 620          * there is more than one file to grep, we will print the filenames. */
 621         if (argv[0] && argv[1])
 622                 print_filename = 1;
 623         /* -H / -h of course override */
 624         if (option_mask32 & OPT_H)
 625                 print_filename = 1;
 626         if (option_mask32 & OPT_h)
 627                 print_filename = 0;
 628
 629         /* If no files were specified, or '-' was specified, take input from
 630          * stdin. Otherwise, we grep through all the files specified. */
 631         matched = 0;
 632         do {
 633                 cur_file = *argv;
 634                 file = stdin;
 635                 if (!cur_file || LONE_DASH(cur_file)) {
 636                         cur_file = "(standard input)";
 637                 } else {
 638                         if (option_mask32 & OPT_r) {
 639                                 struct stat st;
 640                                 if (stat(cur_file, &st) == 0 && S_ISDIR(st.st_mode)) {
 641                                         if (!(option_mask32 & OPT_h))
 642                                                 print_filename = 1;
 643                                         matched += grep_dir(cur_file);
 644                                         goto grep_done;
 645                                 }
 646                         }
 647                         /* else: fopen(dir) will succeed, but reading won't */
 648                         file = fopen_for_read(cur_file);
 649                         if (file == NULL) {
 650                                 if (!SUPPRESS_ERR_MSGS)
 651                                         bb_simple_perror_msg(cur_file);
 652                                 open_errors = 1;
 653                                 continue;
 654                         }
 655                 }
 656                 matched += grep_file(file);
 657                 fclose_if_not_stdin(file);
 658  grep_done: ;
 659         } while (*argv && *++argv);
 660
 661         /* destroy all the elments in the pattern list */
 662         if (ENABLE_FEATURE_CLEAN_UP) {
 663                 while (pattern_head) {
 664                         llist_t *pattern_head_ptr = pattern_head;
 665                         grep_list_data_t *gl = (grep_list_data_t *)pattern_head_ptr->data;
 666
 667                         pattern_head = pattern_head->link;
 668                         if (gl->flg_mem_alocated_compiled & ALLOCATED)
 669                                 free(gl->pattern);
 670                         if (gl->flg_mem_alocated_compiled & COMPILED)
 671                                 regfree(&gl->compiled_regex);
 672                         free(gl);
 673                         free(pattern_head_ptr);
 674                 }
 675         }
 676         /* 0 = success, 1 = failed, 2 = error */
 677         if (open_errors)
 678                 return 2;
 679         return !matched; /* invert return value: 0 = success, 1 = failed */
 680 }