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:" \
  28         IF_FEATURE_GREP_CONTEXT("A:B:C:") \
  29         IF_FEATURE_GREP_EGREP_ALIAS("E") \
  30         IF_DESKTOP("w") \
  31         IF_EXTRA_COMPAT("z") \
  32         "aI"
  33
  34 /* ignored: -a "assume all files to be text" */
  35 /* ignored: -I "assume binary files have no matches" */
  36
  37 enum {
  38         OPTBIT_l, /* list matched file names only */
  39         OPTBIT_n, /* print line# */
  40         OPTBIT_q, /* quiet - exit(EXIT_SUCCESS) of first match */
  41         OPTBIT_v, /* invert the match, to select non-matching lines */
  42         OPTBIT_s, /* suppress errors about file open errors */
  43         OPTBIT_c, /* count matches per file (suppresses normal output) */
  44         OPTBIT_F, /* literal match */
  45         OPTBIT_i, /* case-insensitive */
  46         OPTBIT_H, /* force filename display */
  47         OPTBIT_h, /* inhibit filename display */
  48         OPTBIT_e, /* -e PATTERN */
  49         OPTBIT_f, /* -f FILE_WITH_PATTERNS */
  50         OPTBIT_L, /* list unmatched file names only */
  51         OPTBIT_o, /* show only matching parts of lines */
  52         OPTBIT_r, /* recurse dirs */
  53         OPTBIT_m, /* -m MAX_MATCHES */
  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_DESKTOP(                 OPTBIT_w ,) /* whole word match */
  59         IF_EXTRA_COMPAT(            OPTBIT_z ,) /* input is NUL terminated */
  60         OPT_l = 1 << OPTBIT_l,
  61         OPT_n = 1 << OPTBIT_n,
  62         OPT_q = 1 << OPTBIT_q,
  63         OPT_v = 1 << OPTBIT_v,
  64         OPT_s = 1 << OPTBIT_s,
  65         OPT_c = 1 << OPTBIT_c,
  66         OPT_F = 1 << OPTBIT_F,
  67         OPT_i = 1 << OPTBIT_i,
  68         OPT_H = 1 << OPTBIT_H,
  69         OPT_h = 1 << OPTBIT_h,
  70         OPT_e = 1 << OPTBIT_e,
  71         OPT_f = 1 << OPTBIT_f,
  72         OPT_L = 1 << OPTBIT_L,
  73         OPT_o = 1 << OPTBIT_o,
  74         OPT_r = 1 << OPTBIT_r,
  75         OPT_m = 1 << OPTBIT_m,
  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_w = IF_DESKTOP(                 (1 << OPTBIT_w)) + 0,
  81         OPT_z = IF_EXTRA_COMPAT(            (1 << OPTBIT_z)) + 0,
  82 };
  83
  84 #define PRINT_FILES_WITH_MATCHES    (option_mask32 & OPT_l)
  85 #define PRINT_LINE_NUM              (option_mask32 & OPT_n)
  86 #define BE_QUIET                    (option_mask32 & OPT_q)
  87 #define SUPPRESS_ERR_MSGS           (option_mask32 & OPT_s)
  88 #define PRINT_MATCH_COUNTS          (option_mask32 & OPT_c)
  89 #define FGREP_FLAG                  (option_mask32 & OPT_F)
  90 #define PRINT_FILES_WITHOUT_MATCHES (option_mask32 & OPT_L)
  91 #define NUL_DELIMITED               (option_mask32 & OPT_z)
  92
  93 struct globals {
  94         int max_matches;
  95 #if !ENABLE_EXTRA_COMPAT
  96         int reflags;
  97 #else
  98         RE_TRANSLATE_TYPE case_fold; /* RE_TRANSLATE_TYPE is [[un]signed] char* */
  99 #endif
 100         smalluint invert_search;
 101         smalluint print_filename;
 102         smalluint open_errors;
 103 #if ENABLE_FEATURE_GREP_CONTEXT
 104         smalluint did_print_line;
 105         int lines_before;
 106         int lines_after;
 107         char **before_buf;
 108         IF_EXTRA_COMPAT(size_t *before_buf_size;)
 109         int last_line_printed;
 110 #endif
 111         /* globals used internally */
 112         llist_t *pattern_head;   /* growable list of patterns to match */
 113         const char *cur_file;    /* the current file we are reading */
 114 };
 115 #define G (*(struct globals*)&bb_common_bufsiz1)
 116 #define INIT_G() do { \
 117         struct G_sizecheck { \
 118                 char G_sizecheck[sizeof(G) > COMMON_BUFSIZE ? -1 : 1]; \
 119         }; \
 120 } while (0)
 121 #define max_matches       (G.max_matches         )
 122 #if !ENABLE_EXTRA_COMPAT
 123 # define reflags          (G.reflags             )
 124 #else
 125 # define case_fold        (G.case_fold           )
 126 /* http://www.delorie.com/gnu/docs/regex/regex_46.html */
 127 # define reflags           re_syntax_options
 128 # undef REG_NOSUB
 129 # undef REG_EXTENDED
 130 # undef REG_ICASE
 131 # define REG_NOSUB    bug:is:here /* should not be used */
 132 /* Just RE_SYNTAX_EGREP is not enough, need to enable {n[,[m]]} too */
 133 # define REG_EXTENDED (RE_SYNTAX_EGREP | RE_INTERVALS | RE_NO_BK_BRACES)
 134 # define REG_ICASE    bug:is:here /* should not be used */
 135 #endif
 136 #define invert_search     (G.invert_search       )
 137 #define print_filename    (G.print_filename      )
 138 #define open_errors       (G.open_errors         )
 139 #define did_print_line    (G.did_print_line      )
 140 #define lines_before      (G.lines_before        )
 141 #define lines_after       (G.lines_after         )
 142 #define before_buf        (G.before_buf          )
 143 #define before_buf_size   (G.before_buf_size     )
 144 #define last_line_printed (G.last_line_printed   )
 145 #define pattern_head      (G.pattern_head        )
 146 #define cur_file          (G.cur_file            )
 147
 148
 149 typedef struct grep_list_data_t {
 150         char *pattern;
 151 /* for GNU regex, matched_range must be persistent across grep_file() calls */
 152 #if !ENABLE_EXTRA_COMPAT
 153         regex_t compiled_regex;
 154         regmatch_t matched_range;
 155 #else
 156         struct re_pattern_buffer compiled_regex;
 157         struct re_registers matched_range;
 158 #endif
 159 #define ALLOCATED 1
 160 #define COMPILED 2
 161         int flg_mem_alocated_compiled;
 162 } grep_list_data_t;
 163
 164 #if !ENABLE_EXTRA_COMPAT
 165 #define print_line(line, line_len, linenum, decoration) \
 166         print_line(line, linenum, decoration)
 167 #endif
 168 static void print_line(const char *line, size_t line_len, int linenum, char decoration)
 169 {
 170 #if ENABLE_FEATURE_GREP_CONTEXT
 171         /* Happens when we go to next file, immediately hit match
 172          * and try to print prev context... from prev file! Don't do it */
 173         if (linenum < 1)
 174                 return;
 175         /* possibly print the little '--' separator */
 176         if ((lines_before || lines_after) && did_print_line
 177          && last_line_printed != linenum - 1
 178         ) {
 179                 puts("--");
 180         }
 181         /* guard against printing "--" before first line of first file */
 182         did_print_line = 1;
 183         last_line_printed = linenum;
 184 #endif
 185         if (print_filename)
 186                 printf("%s%c", cur_file, decoration);
 187         if (PRINT_LINE_NUM)
 188                 printf("%i%c", linenum, decoration);
 189         /* Emulate weird GNU grep behavior with -ov */
 190         if ((option_mask32 & (OPT_v|OPT_o)) != (OPT_v|OPT_o)) {
 191 #if !ENABLE_EXTRA_COMPAT
 192                 puts(line);
 193 #else
 194                 fwrite(line, 1, line_len, stdout);
 195                 putchar(NUL_DELIMITED ? '\0' : '\n');
 196 #endif
 197         }
 198 }
 199
 200 #if ENABLE_EXTRA_COMPAT
 201 /* Unlike getline, this one removes trailing '\n' */
 202 static ssize_t FAST_FUNC bb_getline(char **line_ptr, size_t *line_alloc_len, FILE *file)
 203 {
 204         ssize_t res_sz;
 205         char *line;
 206         int delim = (NUL_DELIMITED ? '\0' : '\n');
 207
 208         res_sz = getdelim(line_ptr, line_alloc_len, delim, file);
 209         line = *line_ptr;
 210
 211         if (res_sz > 0) {
 212                 if (line[res_sz - 1] == delim)
 213                         line[--res_sz] = '\0';
 214         } else {
 215                 free(line); /* uclibc allocates a buffer even on EOF. WTF? */
 216         }
 217         return res_sz;
 218 }
 219 #endif
 220
 221 static int grep_file(FILE *file)
 222 {
 223         smalluint found;
 224         int linenum = 0;
 225         int nmatches = 0;
 226 #if !ENABLE_EXTRA_COMPAT
 227         char *line;
 228 #else
 229         char *line = NULL;
 230         ssize_t line_len;
 231         size_t line_alloc_len;
 232 #define rm_so start[0]
 233 #define rm_eo end[0]
 234 #endif
 235 #if ENABLE_FEATURE_GREP_CONTEXT
 236         int print_n_lines_after = 0;
 237         int curpos = 0; /* track where we are in the circular 'before' buffer */
 238         int idx = 0; /* used for iteration through the circular buffer */
 239 #else
 240         enum { print_n_lines_after = 0 };
 241 #endif /* ENABLE_FEATURE_GREP_CONTEXT */
 242
 243         while (
 244 #if !ENABLE_EXTRA_COMPAT
 245                 (line = xmalloc_fgetline(file)) != NULL
 246 #else
 247                 (line_len = bb_getline(&line, &line_alloc_len, file)) >= 0
 248 #endif
 249         ) {
 250                 llist_t *pattern_ptr = pattern_head;
 251                 grep_list_data_t *gl = gl; /* for gcc */
 252
 253                 linenum++;
 254                 found = 0;
 255                 while (pattern_ptr) {
 256                         gl = (grep_list_data_t *)pattern_ptr->data;
 257                         if (FGREP_FLAG) {
 258                                 found |= (strstr(line, gl->pattern) != NULL);
 259                         } else {
 260                                 if (!(gl->flg_mem_alocated_compiled & COMPILED)) {
 261                                         gl->flg_mem_alocated_compiled |= COMPILED;
 262 #if !ENABLE_EXTRA_COMPAT
 263                                         xregcomp(&gl->compiled_regex, gl->pattern, reflags);
 264 #else
 265                                         memset(&gl->compiled_regex, 0, sizeof(gl->compiled_regex));
 266                                         gl->compiled_regex.translate = case_fold; /* for -i */
 267                                         if (re_compile_pattern(gl->pattern, strlen(gl->pattern), &gl->compiled_regex))
 268                                                 bb_error_msg_and_die("bad regex '%s'", gl->pattern);
 269 #endif
 270                                 }
 271 #if !ENABLE_EXTRA_COMPAT
 272                                 gl->matched_range.rm_so = 0;
 273                                 gl->matched_range.rm_eo = 0;
 274 #endif
 275                                 if (
 276 #if !ENABLE_EXTRA_COMPAT
 277                                         regexec(&gl->compiled_regex, line, 1, &gl->matched_range, 0) == 0
 278 #else
 279                                         re_search(&gl->compiled_regex, line, line_len,
 280                                                         /*start:*/ 0, /*range:*/ line_len,
 281                                                         &gl->matched_range) >= 0
 282 #endif
 283                                 ) {
 284                                         if (!(option_mask32 & OPT_w))
 285                                                 found = 1;
 286                                         else {
 287                                                 char c = ' ';
 288                                                 if (gl->matched_range.rm_so)
 289                                                         c = line[gl->matched_range.rm_so - 1];
 290                                                 if (!isalnum(c) && c != '_') {
 291                                                         c = line[gl->matched_range.rm_eo];
 292                                                         if (!c || (!isalnum(c) && c != '_'))
 293                                                                 found = 1;
 294                                                 }
 295                                         }
 296                                 }
 297                         }
 298                         /* If it's non-inverted search, we can stop
 299                          * at first match */
 300                         if (found && !invert_search)
 301                                 goto do_found;
 302                         pattern_ptr = pattern_ptr->link;
 303                 } /* while (pattern_ptr) */
 304
 305                 if (found ^ invert_search) {
 306  do_found:
 307                         /* keep track of matches */
 308                         nmatches++;
 309
 310                         /* quiet/print (non)matching file names only? */
 311                         if (option_mask32 & (OPT_q|OPT_l|OPT_L)) {
 312                                 free(line); /* we don't need line anymore */
 313                                 if (BE_QUIET) {
 314                                         /* manpage says about -q:
 315                                          * "exit immediately with zero status
 316                                          * if any match is found,
 317                                          * even if errors were detected" */
 318                                         exit(EXIT_SUCCESS);
 319                                 }
 320                                 /* if we're just printing filenames, we stop after the first match */
 321                                 if (PRINT_FILES_WITH_MATCHES) {
 322                                         puts(cur_file);
 323                                         /* fall through to "return 1" */
 324                                 }
 325                                 /* OPT_L aka PRINT_FILES_WITHOUT_MATCHES: return early */
 326                                 return 1; /* one match */
 327                         }
 328
 329 #if ENABLE_FEATURE_GREP_CONTEXT
 330                         /* Were we printing context and saw next (unwanted) match? */
 331                         if ((option_mask32 & OPT_m) && nmatches > max_matches)
 332                                 break;
 333 #endif
 334
 335                         /* print the matched line */
 336                         if (PRINT_MATCH_COUNTS == 0) {
 337 #if ENABLE_FEATURE_GREP_CONTEXT
 338                                 int prevpos = (curpos == 0) ? lines_before - 1 : curpos - 1;
 339
 340                                 /* if we were told to print 'before' lines and there is at least
 341                                  * one line in the circular buffer, print them */
 342                                 if (lines_before && before_buf[prevpos] != NULL) {
 343                                         int first_buf_entry_line_num = linenum - lines_before;
 344
 345                                         /* advance to the first entry in the circular buffer, and
 346                                          * figure out the line number is of the first line in the
 347                                          * buffer */
 348                                         idx = curpos;
 349                                         while (before_buf[idx] == NULL) {
 350                                                 idx = (idx + 1) % lines_before;
 351                                                 first_buf_entry_line_num++;
 352                                         }
 353
 354                                         /* now print each line in the buffer, clearing them as we go */
 355                                         while (before_buf[idx] != NULL) {
 356                                                 print_line(before_buf[idx], before_buf_size[idx], first_buf_entry_line_num, '-');
 357                                                 free(before_buf[idx]);
 358                                                 before_buf[idx] = NULL;
 359                                                 idx = (idx + 1) % lines_before;
 360                                                 first_buf_entry_line_num++;
 361                                         }
 362                                 }
 363
 364                                 /* make a note that we need to print 'after' lines */
 365                                 print_n_lines_after = lines_after;
 366 #endif
 367                                 if (option_mask32 & OPT_o) {
 368                                         if (FGREP_FLAG) {
 369                                                 /* -Fo just prints the pattern
 370                                                  * (unless -v: -Fov doesnt print anything at all) */
 371                                                 if (found)
 372                                                         print_line(gl->pattern, strlen(gl->pattern), linenum, ':');
 373                                         } else while (1) {
 374                                                 unsigned end = gl->matched_range.rm_eo;
 375                                                 char old = line[end];
 376                                                 line[end] = '\0';
 377                                                 print_line(line + gl->matched_range.rm_so,
 378                                                                 end - gl->matched_range.rm_so,
 379                                                                 linenum, ':');
 380                                                 line[end] = old;
 381 #if !ENABLE_EXTRA_COMPAT
 382                                                 if (regexec(&gl->compiled_regex, line + end,
 383                                                                 1, &gl->matched_range, REG_NOTBOL) != 0)
 384                                                         break;
 385                                                 gl->matched_range.rm_so += end;
 386                                                 gl->matched_range.rm_eo += end;
 387 #else
 388                                                 if (re_search(&gl->compiled_regex, line, line_len,
 389                                                                 end, line_len - end,
 390                                                                 &gl->matched_range) < 0)
 391                                                         break;
 392 #endif
 393                                         }
 394                                 } else {
 395                                         print_line(line, line_len, linenum, ':');
 396                                 }
 397                         }
 398                 }
 399 #if ENABLE_FEATURE_GREP_CONTEXT
 400                 else { /* no match */
 401                         /* if we need to print some context lines after the last match, do so */
 402                         if (print_n_lines_after) {
 403                                 print_line(line, strlen(line), linenum, '-');
 404                                 print_n_lines_after--;
 405                         } else if (lines_before) {
 406                                 /* Add the line to the circular 'before' buffer */
 407                                 free(before_buf[curpos]);
 408                                 before_buf[curpos] = line;
 409                                 IF_EXTRA_COMPAT(before_buf_size[curpos] = line_len;)
 410                                 curpos = (curpos + 1) % lines_before;
 411                                 /* avoid free(line) - we took the line */
 412                                 line = NULL;
 413                         }
 414                 }
 415
 416 #endif /* ENABLE_FEATURE_GREP_CONTEXT */
 417 #if !ENABLE_EXTRA_COMPAT
 418                 free(line);
 419 #endif
 420                 /* Did we print all context after last requested match? */
 421                 if ((option_mask32 & OPT_m)
 422                  && !print_n_lines_after
 423                  && nmatches == max_matches
 424                 ) {
 425                         break;
 426                 }
 427         } /* while (read line) */
 428
 429         /* special-case file post-processing for options where we don't print line
 430          * matches, just filenames and possibly match counts */
 431
 432         /* grep -c: print [filename:]count, even if count is zero */
 433         if (PRINT_MATCH_COUNTS) {
 434                 if (print_filename)
 435                         printf("%s:", cur_file);
 436                 printf("%d\n", nmatches);
 437         }
 438
 439         /* grep -L: print just the filename */
 440         if (PRINT_FILES_WITHOUT_MATCHES) {
 441                 /* nmatches is zero, no need to check it:
 442                  * we return 1 early if we detected a match
 443                  * and PRINT_FILES_WITHOUT_MATCHES is set */
 444                 puts(cur_file);
 445         }
 446
 447         return nmatches;
 448 }
 449
 450 #if ENABLE_FEATURE_CLEAN_UP
 451 #define new_grep_list_data(p, m) add_grep_list_data(p, m)
 452 static char *add_grep_list_data(char *pattern, int flg_used_mem)
 453 #else
 454 #define new_grep_list_data(p, m) add_grep_list_data(p)
 455 static char *add_grep_list_data(char *pattern)
 456 #endif
 457 {
 458         grep_list_data_t *gl = xzalloc(sizeof(*gl));
 459         gl->pattern = pattern;
 460 #if ENABLE_FEATURE_CLEAN_UP
 461         gl->flg_mem_alocated_compiled = flg_used_mem;
 462 #else
 463         /*gl->flg_mem_alocated_compiled = 0;*/
 464 #endif
 465         return (char *)gl;
 466 }
 467
 468 static void load_regexes_from_file(llist_t *fopt)
 469 {
 470         char *line;
 471         FILE *f;
 472
 473         while (fopt) {
 474                 llist_t *cur = fopt;
 475                 char *ffile = cur->data;
 476
 477                 fopt = cur->link;
 478                 free(cur);
 479                 f = xfopen_stdin(ffile);
 480                 while ((line = xmalloc_fgetline(f)) != NULL) {
 481                         llist_add_to(&pattern_head,
 482                                 new_grep_list_data(line, ALLOCATED));
 483                 }
 484         }
 485 }
 486
 487 static int FAST_FUNC file_action_grep(const char *filename,
 488                         struct stat *statbuf UNUSED_PARAM,
 489                         void* matched,
 490                         int depth UNUSED_PARAM)
 491 {
 492         FILE *file = fopen_for_read(filename);
 493         if (file == NULL) {
 494                 if (!SUPPRESS_ERR_MSGS)
 495                         bb_simple_perror_msg(filename);
 496                 open_errors = 1;
 497                 return 0;
 498         }
 499         cur_file = filename;
 500         *(int*)matched += grep_file(file);
 501         fclose(file);
 502         return 1;
 503 }
 504
 505 static int grep_dir(const char *dir)
 506 {
 507         int matched = 0;
 508         recursive_action(dir,
 509                 /* recurse=yes */ ACTION_RECURSE |
 510                 /* followLinks=no */
 511                 /* depthFirst=yes */ ACTION_DEPTHFIRST,
 512                 /* fileAction= */ file_action_grep,
 513                 /* dirAction= */ NULL,
 514                 /* userData= */ &matched,
 515                 /* depth= */ 0);
 516         return matched;
 517 }
 518
 519 int grep_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 520 int grep_main(int argc, char **argv)
 521 {
 522         FILE *file;
 523         int matched;
 524         llist_t *fopt = NULL;
 525
 526         /* do normal option parsing */
 527 #if ENABLE_FEATURE_GREP_CONTEXT
 528         int Copt;
 529
 530         /* -H unsets -h; -C unsets -A,-B; -e,-f are lists;
 531          * -m,-A,-B,-C have numeric param */
 532         opt_complementary = "H-h:C-AB:e::f::m+:A+:B+:C+";
 533         getopt32(argv,
 534                 OPTSTR_GREP,
 535                 &pattern_head, &fopt, &max_matches,
 536                 &lines_after, &lines_before, &Copt);
 537
 538         if (option_mask32 & OPT_C) {
 539                 /* -C unsets prev -A and -B, but following -A or -B
 540                    may override it */
 541                 if (!(option_mask32 & OPT_A)) /* not overridden */
 542                         lines_after = Copt;
 543                 if (!(option_mask32 & OPT_B)) /* not overridden */
 544                         lines_before = Copt;
 545         }
 546         /* sanity checks */
 547         if (option_mask32 & (OPT_c|OPT_q|OPT_l|OPT_L)) {
 548                 option_mask32 &= ~OPT_n;
 549                 lines_before = 0;
 550                 lines_after = 0;
 551         } else if (lines_before > 0) {
 552                 before_buf = xzalloc(lines_before * sizeof(before_buf[0]));
 553                 IF_EXTRA_COMPAT(before_buf_size = xzalloc(lines_before * sizeof(before_buf_size[0]));)
 554         }
 555 #else
 556         /* with auto sanity checks */
 557         /* -H unsets -h; -c,-q or -l unset -n; -e,-f are lists; -m N */
 558         opt_complementary = "H-h:c-n:q-n:l-n:e::f::m+";
 559         getopt32(argv, OPTSTR_GREP,
 560                 &pattern_head, &fopt, &max_matches);
 561 #endif
 562         invert_search = ((option_mask32 & OPT_v) != 0); /* 0 | 1 */
 563
 564         if (pattern_head != NULL) {
 565                 /* convert char **argv to grep_list_data_t */
 566                 llist_t *cur;
 567
 568                 for (cur = pattern_head; cur; cur = cur->link)
 569                         cur->data = new_grep_list_data(cur->data, 0);
 570         }
 571         if (option_mask32 & OPT_f)
 572                 load_regexes_from_file(fopt);
 573
 574         if (ENABLE_FEATURE_GREP_FGREP_ALIAS && applet_name[0] == 'f')
 575                 option_mask32 |= OPT_F;
 576
 577 #if !ENABLE_EXTRA_COMPAT
 578         if (!(option_mask32 & (OPT_o | OPT_w)))
 579                 reflags = REG_NOSUB;
 580 #endif
 581
 582         if (ENABLE_FEATURE_GREP_EGREP_ALIAS
 583          && (applet_name[0] == 'e' || (option_mask32 & OPT_E))
 584         ) {
 585                 reflags |= REG_EXTENDED;
 586         }
 587 #if ENABLE_EXTRA_COMPAT
 588         else {
 589                 reflags = RE_SYNTAX_GREP;
 590         }
 591 #endif
 592
 593         if (option_mask32 & OPT_i) {
 594 #if !ENABLE_EXTRA_COMPAT
 595                 reflags |= REG_ICASE;
 596 #else
 597                 int i;
 598                 case_fold = xmalloc(256);
 599                 for (i = 0; i < 256; i++)
 600                         case_fold[i] = (unsigned char)i;
 601                 for (i = 'a'; i <= 'z'; i++)
 602                         case_fold[i] = (unsigned char)(i - ('a' - 'A'));
 603 #endif
 604         }
 605
 606         argv += optind;
 607         argc -= 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                 argc--;
 618         }
 619
 620         /* argv[0..(argc-1)] should be names of file to grep through. If
 621          * there is more than one file to grep, we will print the filenames. */
 622         if (argc > 1)
 623                 print_filename = 1;
 624         /* -H / -h of course override */
 625         if (option_mask32 & OPT_H)
 626                 print_filename = 1;
 627         if (option_mask32 & OPT_h)
 628                 print_filename = 0;
 629
 630         /* If no files were specified, or '-' was specified, take input from
 631          * stdin. Otherwise, we grep through all the files specified. */
 632         matched = 0;
 633         do {
 634                 cur_file = *argv++;
 635                 file = stdin;
 636                 if (!cur_file || LONE_DASH(cur_file)) {
 637                         cur_file = "(standard input)";
 638                 } else {
 639                         if (option_mask32 & OPT_r) {
 640                                 struct stat st;
 641                                 if (stat(cur_file, &st) == 0 && S_ISDIR(st.st_mode)) {
 642                                         if (!(option_mask32 & OPT_h))
 643                                                 print_filename = 1;
 644                                         matched += grep_dir(cur_file);
 645                                         goto grep_done;
 646                                 }
 647                         }
 648                         /* else: fopen(dir) will succeed, but reading won't */
 649                         file = fopen_for_read(cur_file);
 650                         if (file == NULL) {
 651                                 if (!SUPPRESS_ERR_MSGS)
 652                                         bb_simple_perror_msg(cur_file);
 653                                 open_errors = 1;
 654                                 continue;
 655                         }
 656                 }
 657                 matched += grep_file(file);
 658                 fclose_if_not_stdin(file);
 659  grep_done: ;
 660         } while (--argc > 0);
 661
 662         /* destroy all the elments in the pattern list */
 663         if (ENABLE_FEATURE_CLEAN_UP) {
 664                 while (pattern_head) {
 665                         llist_t *pattern_head_ptr = pattern_head;
 666                         grep_list_data_t *gl = (grep_list_data_t *)pattern_head_ptr->data;
 667
 668                         pattern_head = pattern_head->link;
 669                         if (gl->flg_mem_alocated_compiled & ALLOCATED)
 670                                 free(gl->pattern);
 671                         if (gl->flg_mem_alocated_compiled & COMPILED)
 672                                 regfree(&gl->compiled_regex);
 673                         free(gl);
 674                         free(pattern_head_ptr);
 675                 }
 676         }
 677         /* 0 = success, 1 = failed, 2 = error */
 678         if (open_errors)
 679                 return 2;
 680         return !matched; /* invert return value: 0 = success, 1 = failed */
 681 }