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 GPLv2 or later, see file LICENSE in this source tree.
   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  * (C) 2006 Jac Goudsmit added -o option
  19  */
  20
  21 //config:config GREP
  22 //config:       bool "grep"
  23 //config:       default y
  24 //config:       help
  25 //config:         grep is used to search files for a specified pattern.
  26 //config:
  27 //config:config EGREP
  28 //config:       bool "egrep"
  29 //config:       default y
  30 //config:       help
  31 //config:         Alias to "grep -E"
  32 //config:
  33 //config:config FGREP
  34 //config:       bool "fgrep"
  35 //config:       default y
  36 //config:       help
  37 //config:         Alias to "grep -F"
  38 //config:
  39 //config:config FEATURE_GREP_CONTEXT
  40 //config:       bool "Enable before and after context flags (-A, -B and -C)"
  41 //config:       default y
  42 //config:       depends on GREP || EGREP
  43 //config:       help
  44 //config:         Print the specified number of leading (-B) and/or trailing (-A)
  45 //config:         context surrounding our matching lines.
  46 //config:         Print the specified number of context lines (-C).
  47
  48 //applet:IF_GREP(APPLET(grep, BB_DIR_BIN, BB_SUID_DROP))
  49 //applet:IF_EGREP(APPLET_ODDNAME(egrep, grep, BB_DIR_BIN, BB_SUID_DROP, egrep))
  50 //applet:IF_FGREP(APPLET_ODDNAME(fgrep, grep, BB_DIR_BIN, BB_SUID_DROP, fgrep))
  51
  52 //kbuild:lib-$(CONFIG_GREP) += grep.o
  53 //kbuild:lib-$(CONFIG_EGREP) += grep.o
  54 //kbuild:lib-$(CONFIG_FGREP) += grep.o
  55
  56 #include "libbb.h"
  57 #include "common_bufsiz.h"
  58 #include "xregex.h"
  59
  60
  61 /* options */
  62 //usage:#define grep_trivial_usage
  63 //usage:       "[-HhnlLoqvsriwFE"
  64 //usage:        IF_EXTRA_COMPAT("z")
  65 //usage:       "] [-m N] "
  66 //usage:        IF_FEATURE_GREP_CONTEXT("[-A/B/C N] ")
  67 //usage:       "PATTERN/-e PATTERN.../-f FILE [FILE]..."
  68 //usage:#define grep_full_usage "\n\n"
  69 //usage:       "Search for PATTERN in FILEs (or stdin)\n"
  70 //usage:     "\n        -H      Add 'filename:' prefix"
  71 //usage:     "\n        -h      Do not add 'filename:' prefix"
  72 //usage:     "\n        -n      Add 'line_no:' prefix"
  73 //usage:     "\n        -l      Show only names of files that match"
  74 //usage:     "\n        -L      Show only names of files that don't match"
  75 //usage:     "\n        -c      Show only count of matching lines"
  76 //usage:     "\n        -o      Show only the matching part of line"
  77 //usage:     "\n        -q      Quiet. Return 0 if PATTERN is found, 1 otherwise"
  78 //usage:     "\n        -v      Select non-matching lines"
  79 //usage:     "\n        -s      Suppress open and read errors"
  80 //usage:     "\n        -r      Recurse"
  81 //usage:     "\n        -i      Ignore case"
  82 //usage:     "\n        -w      Match whole words only"
  83 //usage:     "\n        -x      Match whole lines only"
  84 //usage:     "\n        -F      PATTERN is a literal (not regexp)"
  85 //usage:     "\n        -E      PATTERN is an extended regexp"
  86 //usage:        IF_EXTRA_COMPAT(
  87 //usage:     "\n        -z      Input is NUL terminated"
  88 //usage:        )
  89 //usage:     "\n        -m N    Match up to N times per file"
  90 //usage:        IF_FEATURE_GREP_CONTEXT(
  91 //usage:     "\n        -A N    Print N lines of trailing context"
  92 //usage:     "\n        -B N    Print N lines of leading context"
  93 //usage:     "\n        -C N    Same as '-A N -B N'"
  94 //usage:        )
  95 //usage:     "\n        -e PTRN Pattern to match"
  96 //usage:     "\n        -f FILE Read pattern from file"
  97 //usage:
  98 //usage:#define grep_example_usage
  99 //usage:       "$ grep root /etc/passwd\n"
 100 //usage:       "root:x:0:0:root:/root:/bin/bash\n"
 101 //usage:       "$ grep ^[rR]oo. /etc/passwd\n"
 102 //usage:       "root:x:0:0:root:/root:/bin/bash\n"
 103 //usage:
 104 //usage:#define egrep_trivial_usage NOUSAGE_STR
 105 //usage:#define egrep_full_usage ""
 106 //usage:#define fgrep_trivial_usage NOUSAGE_STR
 107 //usage:#define fgrep_full_usage ""
 108
 109 #define OPTSTR_GREP \
 110         "lnqvscFiHhe:*f:*Lorm:+wx" \
 111         IF_FEATURE_GREP_CONTEXT("A:+B:+C:+") \
 112         "E" \
 113         IF_EXTRA_COMPAT("z") \
 114         "aI"
 115 /* ignored: -a "assume all files to be text" */
 116 /* ignored: -I "assume binary files have no matches" */
 117 enum {
 118         OPTBIT_l, /* list matched file names only */
 119         OPTBIT_n, /* print line# */
 120         OPTBIT_q, /* quiet - exit(EXIT_SUCCESS) of first match */
 121         OPTBIT_v, /* invert the match, to select non-matching lines */
 122         OPTBIT_s, /* suppress errors about file open errors */
 123         OPTBIT_c, /* count matches per file (suppresses normal output) */
 124         OPTBIT_F, /* literal match */
 125         OPTBIT_i, /* case-insensitive */
 126         OPTBIT_H, /* force filename display */
 127         OPTBIT_h, /* inhibit filename display */
 128         OPTBIT_e, /* -e PATTERN */
 129         OPTBIT_f, /* -f FILE_WITH_PATTERNS */
 130         OPTBIT_L, /* list unmatched file names only */
 131         OPTBIT_o, /* show only matching parts of lines */
 132         OPTBIT_r, /* recurse dirs */
 133         OPTBIT_m, /* -m MAX_MATCHES */
 134         OPTBIT_w, /* -w whole word match */
 135         OPTBIT_x, /* -x whole line match */
 136         IF_FEATURE_GREP_CONTEXT(    OPTBIT_A ,) /* -A NUM: after-match context */
 137         IF_FEATURE_GREP_CONTEXT(    OPTBIT_B ,) /* -B NUM: before-match context */
 138         IF_FEATURE_GREP_CONTEXT(    OPTBIT_C ,) /* -C NUM: -A and -B combined */
 139         OPTBIT_E, /* extended regexp */
 140         IF_EXTRA_COMPAT(            OPTBIT_z ,) /* input is NUL terminated */
 141         OPT_l = 1 << OPTBIT_l,
 142         OPT_n = 1 << OPTBIT_n,
 143         OPT_q = 1 << OPTBIT_q,
 144         OPT_v = 1 << OPTBIT_v,
 145         OPT_s = 1 << OPTBIT_s,
 146         OPT_c = 1 << OPTBIT_c,
 147         OPT_F = 1 << OPTBIT_F,
 148         OPT_i = 1 << OPTBIT_i,
 149         OPT_H = 1 << OPTBIT_H,
 150         OPT_h = 1 << OPTBIT_h,
 151         OPT_e = 1 << OPTBIT_e,
 152         OPT_f = 1 << OPTBIT_f,
 153         OPT_L = 1 << OPTBIT_L,
 154         OPT_o = 1 << OPTBIT_o,
 155         OPT_r = 1 << OPTBIT_r,
 156         OPT_m = 1 << OPTBIT_m,
 157         OPT_w = 1 << OPTBIT_w,
 158         OPT_x = 1 << OPTBIT_x,
 159         OPT_A = IF_FEATURE_GREP_CONTEXT(    (1 << OPTBIT_A)) + 0,
 160         OPT_B = IF_FEATURE_GREP_CONTEXT(    (1 << OPTBIT_B)) + 0,
 161         OPT_C = IF_FEATURE_GREP_CONTEXT(    (1 << OPTBIT_C)) + 0,
 162         OPT_E = 1 << OPTBIT_E,
 163         OPT_z = IF_EXTRA_COMPAT(            (1 << OPTBIT_z)) + 0,
 164 };
 165
 166 #define PRINT_FILES_WITH_MATCHES    (option_mask32 & OPT_l)
 167 #define PRINT_LINE_NUM              (option_mask32 & OPT_n)
 168 #define BE_QUIET                    (option_mask32 & OPT_q)
 169 #define SUPPRESS_ERR_MSGS           (option_mask32 & OPT_s)
 170 #define PRINT_MATCH_COUNTS          (option_mask32 & OPT_c)
 171 #define FGREP_FLAG                  (option_mask32 & OPT_F)
 172 #define PRINT_FILES_WITHOUT_MATCHES (option_mask32 & OPT_L)
 173 #define NUL_DELIMITED               (option_mask32 & OPT_z)
 174
 175 struct globals {
 176         int max_matches;
 177 #if !ENABLE_EXTRA_COMPAT
 178         int reflags;
 179 #else
 180         RE_TRANSLATE_TYPE case_fold; /* RE_TRANSLATE_TYPE is [[un]signed] char* */
 181 #endif
 182         smalluint invert_search;
 183         smalluint print_filename;
 184         smalluint open_errors;
 185 #if ENABLE_FEATURE_GREP_CONTEXT
 186         smalluint did_print_line;
 187         int lines_before;
 188         int lines_after;
 189         char **before_buf;
 190         IF_EXTRA_COMPAT(size_t *before_buf_size;)
 191         int last_line_printed;
 192 #endif
 193         /* globals used internally */
 194         llist_t *pattern_head;   /* growable list of patterns to match */
 195         const char *cur_file;    /* the current file we are reading */
 196 } FIX_ALIASING;
 197 #define G (*(struct globals*)bb_common_bufsiz1)
 198 #define INIT_G() do { \
 199         setup_common_bufsiz(); \
 200         BUILD_BUG_ON(sizeof(G) > COMMON_BUFSIZE); \
 201 } while (0)
 202 #define max_matches       (G.max_matches         )
 203 #if !ENABLE_EXTRA_COMPAT
 204 # define reflags          (G.reflags             )
 205 #else
 206 # define case_fold        (G.case_fold           )
 207 /* http://www.delorie.com/gnu/docs/regex/regex_46.html */
 208 # define reflags           re_syntax_options
 209 # undef REG_NOSUB
 210 # undef REG_EXTENDED
 211 # undef REG_ICASE
 212 # define REG_NOSUB    bug:is:here /* should not be used */
 213 /* Just RE_SYNTAX_EGREP is not enough, need to enable {n[,[m]]} too */
 214 # define REG_EXTENDED (RE_SYNTAX_EGREP | RE_INTERVALS | RE_NO_BK_BRACES)
 215 # define REG_ICASE    bug:is:here /* should not be used */
 216 #endif
 217 #define invert_search     (G.invert_search       )
 218 #define print_filename    (G.print_filename      )
 219 #define open_errors       (G.open_errors         )
 220 #define did_print_line    (G.did_print_line      )
 221 #define lines_before      (G.lines_before        )
 222 #define lines_after       (G.lines_after         )
 223 #define before_buf        (G.before_buf          )
 224 #define before_buf_size   (G.before_buf_size     )
 225 #define last_line_printed (G.last_line_printed   )
 226 #define pattern_head      (G.pattern_head        )
 227 #define cur_file          (G.cur_file            )
 228
 229
 230 typedef struct grep_list_data_t {
 231         char *pattern;
 232 /* for GNU regex, matched_range must be persistent across grep_file() calls */
 233 #if !ENABLE_EXTRA_COMPAT
 234         regex_t compiled_regex;
 235         regmatch_t matched_range;
 236 #else
 237         struct re_pattern_buffer compiled_regex;
 238         struct re_registers matched_range;
 239 #endif
 240 #define ALLOCATED 1
 241 #define COMPILED 2
 242         int flg_mem_allocated_compiled;
 243 } grep_list_data_t;
 244
 245 #if !ENABLE_EXTRA_COMPAT
 246 #define print_line(line, line_len, linenum, decoration) \
 247         print_line(line, linenum, decoration)
 248 #endif
 249 static void print_line(const char *line, size_t line_len, int linenum, char decoration)
 250 {
 251 #if ENABLE_FEATURE_GREP_CONTEXT
 252         /* Happens when we go to next file, immediately hit match
 253          * and try to print prev context... from prev file! Don't do it */
 254         if (linenum < 1)
 255                 return;
 256         /* possibly print the little '--' separator */
 257         if ((lines_before || lines_after) && did_print_line
 258          && last_line_printed != linenum - 1
 259         ) {
 260                 puts("--");
 261         }
 262         /* guard against printing "--" before first line of first file */
 263         did_print_line = 1;
 264         last_line_printed = linenum;
 265 #endif
 266         if (print_filename)
 267                 printf("%s%c", cur_file, decoration);
 268         if (PRINT_LINE_NUM)
 269                 printf("%i%c", linenum, decoration);
 270         /* Emulate weird GNU grep behavior with -ov */
 271         if ((option_mask32 & (OPT_v|OPT_o)) != (OPT_v|OPT_o)) {
 272 #if !ENABLE_EXTRA_COMPAT
 273                 puts(line);
 274 #else
 275                 fwrite(line, 1, line_len, stdout);
 276                 putchar(NUL_DELIMITED ? '\0' : '\n');
 277 #endif
 278         }
 279 }
 280
 281 #if ENABLE_EXTRA_COMPAT
 282 /* Unlike getline, this one removes trailing '\n' */
 283 static ssize_t FAST_FUNC bb_getline(char **line_ptr, size_t *line_alloc_len, FILE *file)
 284 {
 285         ssize_t res_sz;
 286         char *line;
 287         int delim = (NUL_DELIMITED ? '\0' : '\n');
 288
 289         res_sz = getdelim(line_ptr, line_alloc_len, delim, file);
 290         line = *line_ptr;
 291
 292         if (res_sz > 0) {
 293                 if (line[res_sz - 1] == delim)
 294                         line[--res_sz] = '\0';
 295         } else {
 296                 free(line); /* uclibc allocates a buffer even on EOF. WTF? */
 297         }
 298         return res_sz;
 299 }
 300 #endif
 301
 302 static int grep_file(FILE *file)
 303 {
 304         smalluint found;
 305         int linenum = 0;
 306         int nmatches = 0;
 307 #if !ENABLE_EXTRA_COMPAT
 308         char *line;
 309 #else
 310         char *line = NULL;
 311         ssize_t line_len;
 312         size_t line_alloc_len;
 313 # define rm_so start[0]
 314 # define rm_eo end[0]
 315 #endif
 316 #if ENABLE_FEATURE_GREP_CONTEXT
 317         int print_n_lines_after = 0;
 318         int curpos = 0; /* track where we are in the circular 'before' buffer */
 319         int idx = 0; /* used for iteration through the circular buffer */
 320 #else
 321         enum { print_n_lines_after = 0 };
 322 #endif
 323
 324         while (
 325 #if !ENABLE_EXTRA_COMPAT
 326                 (line = xmalloc_fgetline(file)) != NULL
 327 #else
 328                 (line_len = bb_getline(&line, &line_alloc_len, file)) >= 0
 329 #endif
 330         ) {
 331                 llist_t *pattern_ptr = pattern_head;
 332                 grep_list_data_t *gl = gl; /* for gcc */
 333
 334                 linenum++;
 335                 found = 0;
 336                 while (pattern_ptr) {
 337                         gl = (grep_list_data_t *)pattern_ptr->data;
 338                         if (FGREP_FLAG) {
 339                                 char *match;
 340                                 char *str = line;
 341  opt_f_again:
 342                                 match = ((option_mask32 & OPT_i)
 343                                         ? strcasestr(str, gl->pattern)
 344                                         : strstr(str, gl->pattern)
 345                                         );
 346                                 if (match) {
 347                                         if (option_mask32 & OPT_x) {
 348                                                 if (match != str)
 349                                                         goto opt_f_not_found;
 350                                                 if (str[strlen(gl->pattern)] != '\0')
 351                                                         goto opt_f_not_found;
 352                                         } else
 353                                         if (option_mask32 & OPT_w) {
 354                                                 char c = (match != str) ? match[-1] : ' ';
 355                                                 if (!isalnum(c) && c != '_') {
 356                                                         c = match[strlen(gl->pattern)];
 357                                                         if (!c || (!isalnum(c) && c != '_'))
 358                                                                 goto opt_f_found;
 359                                                 }
 360                                                 str = match + 1;
 361                                                 goto opt_f_again;
 362                                         }
 363  opt_f_found:
 364                                         found = 1;
 365  opt_f_not_found: ;
 366                                 }
 367                         } else {
 368 #if ENABLE_EXTRA_COMPAT
 369                                 unsigned start_pos;
 370 #else
 371                                 int match_flg;
 372 #endif
 373                                 char *match_at;
 374
 375                                 if (!(gl->flg_mem_allocated_compiled & COMPILED)) {
 376                                         gl->flg_mem_allocated_compiled |= COMPILED;
 377 #if !ENABLE_EXTRA_COMPAT
 378                                         xregcomp(&gl->compiled_regex, gl->pattern, reflags);
 379 #else
 380                                         memset(&gl->compiled_regex, 0, sizeof(gl->compiled_regex));
 381                                         gl->compiled_regex.translate = case_fold; /* for -i */
 382                                         if (re_compile_pattern(gl->pattern, strlen(gl->pattern), &gl->compiled_regex))
 383                                                 bb_error_msg_and_die("bad regex '%s'", gl->pattern);
 384 #endif
 385                                 }
 386 #if !ENABLE_EXTRA_COMPAT
 387                                 gl->matched_range.rm_so = 0;
 388                                 gl->matched_range.rm_eo = 0;
 389                                 match_flg = 0;
 390 #else
 391                                 start_pos = 0;
 392 #endif
 393                                 match_at = line;
 394  opt_w_again:
 395 //bb_error_msg("'%s' start_pos:%d line_len:%d", match_at, start_pos, line_len);
 396                                 if (
 397 #if !ENABLE_EXTRA_COMPAT
 398                                         regexec(&gl->compiled_regex, match_at, 1, &gl->matched_range, match_flg) == 0
 399 #else
 400                                         re_search(&gl->compiled_regex, match_at, line_len,
 401                                                         start_pos, /*range:*/ line_len,
 402                                                         &gl->matched_range) >= 0
 403 #endif
 404                                 ) {
 405                                         if (option_mask32 & OPT_x) {
 406                                                 found = (gl->matched_range.rm_so == 0
 407                                                          && match_at[gl->matched_range.rm_eo] == '\0');
 408                                         } else
 409                                         if (!(option_mask32 & OPT_w)) {
 410                                                 found = 1;
 411                                         } else {
 412                                                 char c = ' ';
 413                                                 if (match_at > line || gl->matched_range.rm_so != 0) {
 414                                                         c = match_at[gl->matched_range.rm_so - 1];
 415                                                 }
 416                                                 if (!isalnum(c) && c != '_') {
 417                                                         c = match_at[gl->matched_range.rm_eo];
 418                                                 }
 419                                                 if (!isalnum(c) && c != '_') {
 420                                                         found = 1;
 421                                                 } else {
 422                         /*
 423                          * Why check gl->matched_range.rm_eo?
 424                          * Zero-length match makes -w skip the line:
 425                          * "echo foo | grep ^" prints "foo",
 426                          * "echo foo | grep -w ^" prints nothing.
 427                          * Without such check, we can loop forever.
 428                          */
 429 #if !ENABLE_EXTRA_COMPAT
 430                                                         if (gl->matched_range.rm_eo != 0) {
 431                                                                 match_at += gl->matched_range.rm_eo;
 432                                                                 match_flg |= REG_NOTBOL;
 433                                                                 goto opt_w_again;
 434                                                         }
 435 #else
 436                                                         if (gl->matched_range.rm_eo > start_pos) {
 437                                                                 start_pos = gl->matched_range.rm_eo;
 438                                                                 goto opt_w_again;
 439                                                         }
 440 #endif
 441                                                 }
 442                                         }
 443                                 }
 444                         }
 445                         /* If it's non-inverted search, we can stop
 446                          * at first match */
 447                         if (found && !invert_search)
 448                                 goto do_found;
 449                         pattern_ptr = pattern_ptr->link;
 450                 } /* while (pattern_ptr) */
 451
 452                 if (found ^ invert_search) {
 453  do_found:
 454                         /* keep track of matches */
 455                         nmatches++;
 456
 457                         /* quiet/print (non)matching file names only? */
 458                         if (option_mask32 & (OPT_q|OPT_l|OPT_L)) {
 459                                 free(line); /* we don't need line anymore */
 460                                 if (BE_QUIET) {
 461                                         /* manpage says about -q:
 462                                          * "exit immediately with zero status
 463                                          * if any match is found,
 464                                          * even if errors were detected" */
 465                                         exit(EXIT_SUCCESS);
 466                                 }
 467                                 /* if we're just printing filenames, we stop after the first match */
 468                                 if (PRINT_FILES_WITH_MATCHES) {
 469                                         puts(cur_file);
 470                                         /* fall through to "return 1" */
 471                                 }
 472                                 /* OPT_L aka PRINT_FILES_WITHOUT_MATCHES: return early */
 473                                 return 1; /* one match */
 474                         }
 475
 476 #if ENABLE_FEATURE_GREP_CONTEXT
 477                         /* Were we printing context and saw next (unwanted) match? */
 478                         if ((option_mask32 & OPT_m) && nmatches > max_matches)
 479                                 break;
 480 #endif
 481
 482                         /* print the matched line */
 483                         if (PRINT_MATCH_COUNTS == 0) {
 484 #if ENABLE_FEATURE_GREP_CONTEXT
 485                                 int prevpos = (curpos == 0) ? lines_before - 1 : curpos - 1;
 486
 487                                 /* if we were told to print 'before' lines and there is at least
 488                                  * one line in the circular buffer, print them */
 489                                 if (lines_before && before_buf[prevpos] != NULL) {
 490                                         int first_buf_entry_line_num = linenum - lines_before;
 491
 492                                         /* advance to the first entry in the circular buffer, and
 493                                          * figure out the line number is of the first line in the
 494                                          * buffer */
 495                                         idx = curpos;
 496                                         while (before_buf[idx] == NULL) {
 497                                                 idx = (idx + 1) % lines_before;
 498                                                 first_buf_entry_line_num++;
 499                                         }
 500
 501                                         /* now print each line in the buffer, clearing them as we go */
 502                                         while (before_buf[idx] != NULL) {
 503                                                 print_line(before_buf[idx], before_buf_size[idx], first_buf_entry_line_num, '-');
 504                                                 free(before_buf[idx]);
 505                                                 before_buf[idx] = NULL;
 506                                                 idx = (idx + 1) % lines_before;
 507                                                 first_buf_entry_line_num++;
 508                                         }
 509                                 }
 510
 511                                 /* make a note that we need to print 'after' lines */
 512                                 print_n_lines_after = lines_after;
 513 #endif
 514                                 if (option_mask32 & OPT_o) {
 515                                         if (FGREP_FLAG) {
 516                                                 /* -Fo just prints the pattern
 517                                                  * (unless -v: -Fov doesnt print anything at all) */
 518                                                 if (found)
 519                                                         print_line(gl->pattern, strlen(gl->pattern), linenum, ':');
 520                                         } else while (1) {
 521                                                 unsigned start = gl->matched_range.rm_so;
 522                                                 unsigned end = gl->matched_range.rm_eo;
 523                                                 unsigned len = end - start;
 524                                                 char old = line[end];
 525                                                 line[end] = '\0';
 526                                                 /* Empty match is not printed: try "echo test | grep -o ''" */
 527                                                 if (len != 0)
 528                                                         print_line(line + start, len, linenum, ':');
 529                                                 if (old == '\0')
 530                                                         break;
 531                                                 line[end] = old;
 532                                                 if (len == 0)
 533                                                         end++;
 534 #if !ENABLE_EXTRA_COMPAT
 535                                                 if (regexec(&gl->compiled_regex, line + end,
 536                                                                 1, &gl->matched_range, REG_NOTBOL) != 0)
 537                                                         break;
 538                                                 gl->matched_range.rm_so += end;
 539                                                 gl->matched_range.rm_eo += end;
 540 #else
 541                                                 if (re_search(&gl->compiled_regex, line, line_len,
 542                                                                 end, line_len - end,
 543                                                                 &gl->matched_range) < 0)
 544                                                         break;
 545 #endif
 546                                         }
 547                                 } else {
 548                                         print_line(line, line_len, linenum, ':');
 549                                 }
 550                         }
 551                 }
 552 #if ENABLE_FEATURE_GREP_CONTEXT
 553                 else { /* no match */
 554                         /* if we need to print some context lines after the last match, do so */
 555                         if (print_n_lines_after) {
 556                                 print_line(line, strlen(line), linenum, '-');
 557                                 print_n_lines_after--;
 558                         } else if (lines_before) {
 559                                 /* Add the line to the circular 'before' buffer */
 560                                 free(before_buf[curpos]);
 561                                 before_buf[curpos] = line;
 562                                 IF_EXTRA_COMPAT(before_buf_size[curpos] = line_len;)
 563                                 curpos = (curpos + 1) % lines_before;
 564                                 /* avoid free(line) - we took the line */
 565                                 line = NULL;
 566                         }
 567                 }
 568
 569 #endif /* ENABLE_FEATURE_GREP_CONTEXT */
 570 #if !ENABLE_EXTRA_COMPAT
 571                 free(line);
 572 #endif
 573                 /* Did we print all context after last requested match? */
 574                 if ((option_mask32 & OPT_m)
 575                  && !print_n_lines_after
 576                  && nmatches == max_matches
 577                 ) {
 578                         break;
 579                 }
 580         } /* while (read line) */
 581
 582         /* special-case file post-processing for options where we don't print line
 583          * matches, just filenames and possibly match counts */
 584
 585         /* grep -c: print [filename:]count, even if count is zero */
 586         if (PRINT_MATCH_COUNTS) {
 587                 if (print_filename)
 588                         printf("%s:", cur_file);
 589                 printf("%d\n", nmatches);
 590         }
 591
 592         /* grep -L: print just the filename */
 593         if (PRINT_FILES_WITHOUT_MATCHES) {
 594                 /* nmatches is zero, no need to check it:
 595                  * we return 1 early if we detected a match
 596                  * and PRINT_FILES_WITHOUT_MATCHES is set */
 597                 puts(cur_file);
 598         }
 599
 600         return nmatches;
 601 }
 602
 603 #if ENABLE_FEATURE_CLEAN_UP
 604 #define new_grep_list_data(p, m) add_grep_list_data(p, m)
 605 static char *add_grep_list_data(char *pattern, int flg_used_mem)
 606 #else
 607 #define new_grep_list_data(p, m) add_grep_list_data(p)
 608 static char *add_grep_list_data(char *pattern)
 609 #endif
 610 {
 611         grep_list_data_t *gl = xzalloc(sizeof(*gl));
 612         gl->pattern = pattern;
 613 #if ENABLE_FEATURE_CLEAN_UP
 614         gl->flg_mem_allocated_compiled = flg_used_mem;
 615 #else
 616         /*gl->flg_mem_allocated_compiled = 0;*/
 617 #endif
 618         return (char *)gl;
 619 }
 620
 621 static void load_regexes_from_file(llist_t *fopt)
 622 {
 623         while (fopt) {
 624                 char *line;
 625                 FILE *fp;
 626                 llist_t *cur = fopt;
 627                 char *ffile = cur->data;
 628
 629                 fopt = cur->link;
 630                 free(cur);
 631                 fp = xfopen_stdin(ffile);
 632                 while ((line = xmalloc_fgetline(fp)) != NULL) {
 633                         llist_add_to(&pattern_head,
 634                                 new_grep_list_data(line, ALLOCATED));
 635                 }
 636                 fclose_if_not_stdin(fp);
 637         }
 638 }
 639
 640 static int FAST_FUNC file_action_grep(const char *filename,
 641                         struct stat *statbuf UNUSED_PARAM,
 642                         void* matched,
 643                         int depth UNUSED_PARAM)
 644 {
 645         FILE *file = fopen_for_read(filename);
 646         if (file == NULL) {
 647                 if (!SUPPRESS_ERR_MSGS)
 648                         bb_simple_perror_msg(filename);
 649                 open_errors = 1;
 650                 return 0;
 651         }
 652         cur_file = filename;
 653         *(int*)matched += grep_file(file);
 654         fclose(file);
 655         return 1;
 656 }
 657
 658 static int grep_dir(const char *dir)
 659 {
 660         int matched = 0;
 661         recursive_action(dir,
 662                 /* recurse=yes */ ACTION_RECURSE |
 663                 /* followLinks=command line only */ ACTION_FOLLOWLINKS_L0 |
 664                 /* depthFirst=yes */ ACTION_DEPTHFIRST,
 665                 /* fileAction= */ file_action_grep,
 666                 /* dirAction= */ NULL,
 667                 /* userData= */ &matched,
 668                 /* depth= */ 0);
 669         return matched;
 670 }
 671
 672 int grep_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 673 int grep_main(int argc UNUSED_PARAM, char **argv)
 674 {
 675         FILE *file;
 676         int matched;
 677         llist_t *fopt = NULL;
 678 #if ENABLE_FEATURE_GREP_CONTEXT
 679         int Copt, opts;
 680 #endif
 681         INIT_G();
 682
 683         /* For grep, exitcode of 1 is "not found". Other errors are 2: */
 684         xfunc_error_retval = 2;
 685
 686         /* do normal option parsing */
 687 #if ENABLE_FEATURE_GREP_CONTEXT
 688         /* -H unsets -h; -C unsets -A,-B; -e,-f are lists;
 689          * -m,-A,-B,-C have numeric param */
 690         opt_complementary = "H-h:C-AB";
 691         opts = getopt32(argv,
 692                 OPTSTR_GREP,
 693                 &pattern_head, &fopt, &max_matches,
 694                 &lines_after, &lines_before, &Copt);
 695
 696         if (opts & OPT_C) {
 697                 /* -C unsets prev -A and -B, but following -A or -B
 698                  * may override it */
 699                 if (!(opts & OPT_A)) /* not overridden */
 700                         lines_after = Copt;
 701                 if (!(opts & OPT_B)) /* not overridden */
 702                         lines_before = Copt;
 703         }
 704         /* sanity checks */
 705         if (opts & (OPT_c|OPT_q|OPT_l|OPT_L)) {
 706                 option_mask32 &= ~OPT_n;
 707                 lines_before = 0;
 708                 lines_after = 0;
 709         } else if (lines_before > 0) {
 710                 if (lines_before > INT_MAX / sizeof(long long))
 711                         lines_before = INT_MAX / sizeof(long long);
 712                 /* overflow in (lines_before * sizeof(x)) is prevented (above) */
 713                 before_buf = xzalloc(lines_before * sizeof(before_buf[0]));
 714                 IF_EXTRA_COMPAT(before_buf_size = xzalloc(lines_before * sizeof(before_buf_size[0]));)
 715         }
 716 #else
 717         /* with auto sanity checks */
 718         /* -H unsets -h; -c,-q or -l unset -n; -e,-f are lists; -m N */
 719         opt_complementary = "H-h:c-n:q-n:l-n:";
 720         getopt32(argv, OPTSTR_GREP,
 721                 &pattern_head, &fopt, &max_matches);
 722 #endif
 723         invert_search = ((option_mask32 & OPT_v) != 0); /* 0 | 1 */
 724
 725         {       /* convert char **argv to grep_list_data_t */
 726                 llist_t *cur;
 727                 for (cur = pattern_head; cur; cur = cur->link)
 728                         cur->data = new_grep_list_data(cur->data, 0);
 729         }
 730         if (option_mask32 & OPT_f) {
 731                 load_regexes_from_file(fopt);
 732                 if (!pattern_head) { /* -f EMPTY_FILE? */
 733                         /* GNU grep treats it as "nothing matches" */
 734                         llist_add_to(&pattern_head, new_grep_list_data((char*) "", 0));
 735                         invert_search ^= 1;
 736                 }
 737         }
 738
 739         if (ENABLE_FGREP && applet_name[0] == 'f')
 740                 option_mask32 |= OPT_F;
 741
 742 #if !ENABLE_EXTRA_COMPAT
 743         if (!(option_mask32 & (OPT_o | OPT_w | OPT_x)))
 744                 reflags = REG_NOSUB;
 745 #endif
 746
 747         if ((ENABLE_EGREP && applet_name[0] == 'e')
 748          || (option_mask32 & OPT_E)
 749         ) {
 750                 reflags |= REG_EXTENDED;
 751         }
 752 #if ENABLE_EXTRA_COMPAT
 753         else {
 754                 reflags = RE_SYNTAX_GREP;
 755         }
 756 #endif
 757
 758         if (option_mask32 & OPT_i) {
 759 #if !ENABLE_EXTRA_COMPAT
 760                 reflags |= REG_ICASE;
 761 #else
 762                 int i;
 763                 case_fold = xmalloc(256);
 764                 for (i = 0; i < 256; i++)
 765                         case_fold[i] = (unsigned char)i;
 766                 for (i = 'a'; i <= 'z'; i++)
 767                         case_fold[i] = (unsigned char)(i - ('a' - 'A'));
 768 #endif
 769         }
 770
 771         argv += optind;
 772
 773         /* if we didn't get a pattern from -e and no command file was specified,
 774          * first parameter should be the pattern. no pattern, no worky */
 775         if (pattern_head == NULL) {
 776                 char *pattern;
 777                 if (*argv == NULL)
 778                         bb_show_usage();
 779                 pattern = new_grep_list_data(*argv++, 0);
 780                 llist_add_to(&pattern_head, pattern);
 781         }
 782
 783         /* argv[0..(argc-1)] should be names of file to grep through. If
 784          * there is more than one file to grep, we will print the filenames. */
 785         if (argv[0] && argv[1])
 786                 print_filename = 1;
 787         /* -H / -h of course override */
 788         if (option_mask32 & OPT_H)
 789                 print_filename = 1;
 790         if (option_mask32 & OPT_h)
 791                 print_filename = 0;
 792
 793         /* If no files were specified, or '-' was specified, take input from
 794          * stdin. Otherwise, we grep through all the files specified. */
 795         matched = 0;
 796         do {
 797                 cur_file = *argv;
 798                 file = stdin;
 799                 if (!cur_file || LONE_DASH(cur_file)) {
 800                         cur_file = "(standard input)";
 801                 } else {
 802                         if (option_mask32 & OPT_r) {
 803                                 struct stat st;
 804                                 if (stat(cur_file, &st) == 0 && S_ISDIR(st.st_mode)) {
 805                                         if (!(option_mask32 & OPT_h))
 806                                                 print_filename = 1;
 807                                         matched += grep_dir(cur_file);
 808                                         goto grep_done;
 809                                 }
 810                         }
 811                         /* else: fopen(dir) will succeed, but reading won't */
 812                         file = fopen_for_read(cur_file);
 813                         if (file == NULL) {
 814                                 if (!SUPPRESS_ERR_MSGS)
 815                                         bb_simple_perror_msg(cur_file);
 816                                 open_errors = 1;
 817                                 continue;
 818                         }
 819                 }
 820                 matched += grep_file(file);
 821                 fclose_if_not_stdin(file);
 822  grep_done: ;
 823         } while (*argv && *++argv);
 824
 825         /* destroy all the elments in the pattern list */
 826         if (ENABLE_FEATURE_CLEAN_UP) {
 827                 while (pattern_head) {
 828                         llist_t *pattern_head_ptr = pattern_head;
 829                         grep_list_data_t *gl = (grep_list_data_t *)pattern_head_ptr->data;
 830
 831                         pattern_head = pattern_head->link;
 832                         if (gl->flg_mem_allocated_compiled & ALLOCATED)
 833                                 free(gl->pattern);
 834                         if (gl->flg_mem_allocated_compiled & COMPILED)
 835                                 regfree(&gl->compiled_regex);
 836                         free(gl);
 837                         free(pattern_head_ptr);
 838                 }
 839         }
 840         /* 0 = success, 1 = failed, 2 = error */
 841         if (open_errors)
 842                 return 2;
 843         return !matched; /* invert return value: 0 = success, 1 = failed */
 844 }