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