hush: add leak detector helper; fix/add tests for it
[oweals/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 /*
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         USE_FEATURE_GREP_CONTEXT("A:B:C:") \
29         USE_FEATURE_GREP_EGREP_ALIAS("E") \
30         USE_DESKTOP("w") \
31         USE_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         USE_FEATURE_GREP_CONTEXT(    OPTBIT_A ,) /* -A NUM: after-match context */
55         USE_FEATURE_GREP_CONTEXT(    OPTBIT_B ,) /* -B NUM: before-match context */
56         USE_FEATURE_GREP_CONTEXT(    OPTBIT_C ,) /* -C NUM: -A and -B combined */
57         USE_FEATURE_GREP_EGREP_ALIAS(OPTBIT_E ,) /* extended regexp */
58         USE_DESKTOP(                 OPTBIT_w ,) /* whole word match */
59         USE_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 = USE_FEATURE_GREP_CONTEXT(    (1 << OPTBIT_A)) + 0,
77         OPT_B = USE_FEATURE_GREP_CONTEXT(    (1 << OPTBIT_B)) + 0,
78         OPT_C = USE_FEATURE_GREP_CONTEXT(    (1 << OPTBIT_C)) + 0,
79         OPT_E = USE_FEATURE_GREP_EGREP_ALIAS((1 << OPTBIT_E)) + 0,
80         OPT_w = USE_DESKTOP(                 (1 << OPTBIT_w)) + 0,
81         OPT_z = USE_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         USE_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 #define REG_EXTENDED RE_SYNTAX_EGREP
133 #define REG_ICASE    bug:is:here /* should not be used */
134 #endif
135 #define invert_search     (G.invert_search       )
136 #define print_filename    (G.print_filename      )
137 #define open_errors       (G.open_errors         )
138 #define did_print_line    (G.did_print_line      )
139 #define lines_before      (G.lines_before        )
140 #define lines_after       (G.lines_after         )
141 #define before_buf        (G.before_buf          )
142 #define before_buf_size   (G.before_buf_size     )
143 #define last_line_printed (G.last_line_printed   )
144 #define pattern_head      (G.pattern_head        )
145 #define cur_file          (G.cur_file            )
146
147
148 typedef struct grep_list_data_t {
149         char *pattern;
150 /* for GNU regex, matched_range must be persistent across grep_file() calls */
151 #if !ENABLE_EXTRA_COMPAT
152         regex_t compiled_regex;
153         regmatch_t matched_range;
154 #else
155         struct re_pattern_buffer compiled_regex;
156         struct re_registers matched_range;
157 #endif
158 #define ALLOCATED 1
159 #define COMPILED 2
160         int flg_mem_alocated_compiled;
161 } grep_list_data_t;
162
163 #if !ENABLE_EXTRA_COMPAT
164 #define print_line(line, line_len, linenum, decoration) \
165         print_line(line, linenum, decoration)
166 #endif
167 static void print_line(const char *line, size_t line_len, int linenum, char decoration)
168 {
169 #if ENABLE_FEATURE_GREP_CONTEXT
170         /* Happens when we go to next file, immediately hit match
171          * and try to print prev context... from prev file! Don't do it */
172         if (linenum < 1)
173                 return;
174         /* possibly print the little '--' separator */
175         if ((lines_before || lines_after) && did_print_line
176          && last_line_printed != linenum - 1
177         ) {
178                 puts("--");
179         }
180         /* guard against printing "--" before first line of first file */
181         did_print_line = 1;
182         last_line_printed = linenum;
183 #endif
184         if (print_filename)
185                 printf("%s%c", cur_file, decoration);
186         if (PRINT_LINE_NUM)
187                 printf("%i%c", linenum, decoration);
188         /* Emulate weird GNU grep behavior with -ov */
189         if ((option_mask32 & (OPT_v|OPT_o)) != (OPT_v|OPT_o)) {
190 #if !ENABLE_EXTRA_COMPAT
191                 puts(line);
192 #else
193                 fwrite(line, 1, line_len, stdout);
194                 putchar(NUL_DELIMITED ? '\0' : '\n');
195 #endif
196         }
197 }
198
199 #if ENABLE_EXTRA_COMPAT
200 /* Unlike getline, this one removes trailing '\n' */
201 static ssize_t FAST_FUNC bb_getline(char **line_ptr, size_t *line_alloc_len, FILE *file)
202 {
203         ssize_t res_sz;
204         char *line;
205         int delim = (NUL_DELIMITED ? '\0' : '\n');
206
207         res_sz = getdelim(line_ptr, line_alloc_len, delim, file);
208         line = *line_ptr;
209
210         if (res_sz > 0) {
211                 if (line[res_sz - 1] == delim)
212                         line[--res_sz] = '\0';
213         } else {
214                 free(line); /* uclibc allocates a buffer even on EOF. WTF? */
215         }
216         return res_sz;
217 }
218 #endif
219
220 static int grep_file(FILE *file)
221 {
222         smalluint found;
223         int linenum = 0;
224         int nmatches = 0;
225 #if !ENABLE_EXTRA_COMPAT
226         char *line;
227 #else
228         char *line = NULL;
229         ssize_t line_len;
230         size_t line_alloc_len;
231 #define rm_so start[0]
232 #define rm_eo end[0]
233 #endif
234 #if ENABLE_FEATURE_GREP_CONTEXT
235         int print_n_lines_after = 0;
236         int curpos = 0; /* track where we are in the circular 'before' buffer */
237         int idx = 0; /* used for iteration through the circular buffer */
238 #else
239         enum { print_n_lines_after = 0 };
240 #endif /* ENABLE_FEATURE_GREP_CONTEXT */
241
242         while (
243 #if !ENABLE_EXTRA_COMPAT
244                 (line = xmalloc_fgetline(file)) != NULL
245 #else
246                 (line_len = bb_getline(&line, &line_alloc_len, file)) >= 0
247 #endif
248         ) {
249                 llist_t *pattern_ptr = pattern_head;
250                 grep_list_data_t *gl = gl; /* for gcc */
251
252                 linenum++;
253                 found = 0;
254                 while (pattern_ptr) {
255                         gl = (grep_list_data_t *)pattern_ptr->data;
256                         if (FGREP_FLAG) {
257                                 found |= (strstr(line, gl->pattern) != NULL);
258                         } else {
259                                 if (!(gl->flg_mem_alocated_compiled & COMPILED)) {
260                                         gl->flg_mem_alocated_compiled |= COMPILED;
261 #if !ENABLE_EXTRA_COMPAT
262                                         xregcomp(&gl->compiled_regex, gl->pattern, reflags);
263 #else
264                                         memset(&gl->compiled_regex, 0, sizeof(gl->compiled_regex));
265                                         gl->compiled_regex.translate = case_fold; /* for -i */
266                                         if (re_compile_pattern(gl->pattern, strlen(gl->pattern), &gl->compiled_regex))
267                                                 bb_error_msg_and_die("bad regex '%s'", gl->pattern);
268 #endif
269                                 }
270 #if !ENABLE_EXTRA_COMPAT
271                                 gl->matched_range.rm_so = 0;
272                                 gl->matched_range.rm_eo = 0;
273 #endif
274                                 if (
275 #if !ENABLE_EXTRA_COMPAT
276                                         regexec(&gl->compiled_regex, line, 1, &gl->matched_range, 0) == 0
277 #else
278                                         re_search(&gl->compiled_regex, line, line_len,
279                                                         /*start:*/ 0, /*range:*/ line_len,
280                                                         &gl->matched_range) >= 0
281 #endif
282                                 ) {
283                                         if (!(option_mask32 & OPT_w))
284                                                 found = 1;
285                                         else {
286                                                 char c = ' ';
287                                                 if (gl->matched_range.rm_so)
288                                                         c = line[gl->matched_range.rm_so - 1];
289                                                 if (!isalnum(c) && c != '_') {
290                                                         c = line[gl->matched_range.rm_eo];
291                                                         if (!c || (!isalnum(c) && c != '_'))
292                                                                 found = 1;
293                                                 }
294                                         }
295                                 }
296                         }
297                         /* If it's non-inverted search, we can stop
298                          * at first match */
299                         if (found && !invert_search)
300                                 goto do_found;
301                         pattern_ptr = pattern_ptr->link;
302                 } /* while (pattern_ptr) */
303
304                 if (found ^ invert_search) {
305  do_found:
306                         /* keep track of matches */
307                         nmatches++;
308
309                         /* quiet/print (non)matching file names only? */
310                         if (option_mask32 & (OPT_q|OPT_l|OPT_L)) {
311                                 free(line); /* we don't need line anymore */
312                                 if (BE_QUIET) {
313                                         /* manpage says about -q:
314                                          * "exit immediately with zero status
315                                          * if any match is found,
316                                          * even if errors were detected" */
317                                         exit(EXIT_SUCCESS);
318                                 }
319                                 /* if we're just printing filenames, we stop after the first match */
320                                 if (PRINT_FILES_WITH_MATCHES) {
321                                         puts(cur_file);
322                                         /* fall through to "return 1" */
323                                 }
324                                 /* OPT_L aka PRINT_FILES_WITHOUT_MATCHES: return early */
325                                 return 1; /* one match */
326                         }
327
328 #if ENABLE_FEATURE_GREP_CONTEXT
329                         /* Were we printing context and saw next (unwanted) match? */
330                         if ((option_mask32 & OPT_m) && nmatches > max_matches)
331                                 break;
332 #endif
333
334                         /* print the matched line */
335                         if (PRINT_MATCH_COUNTS == 0) {
336 #if ENABLE_FEATURE_GREP_CONTEXT
337                                 int prevpos = (curpos == 0) ? lines_before - 1 : curpos - 1;
338
339                                 /* if we were told to print 'before' lines and there is at least
340                                  * one line in the circular buffer, print them */
341                                 if (lines_before && before_buf[prevpos] != NULL) {
342                                         int first_buf_entry_line_num = linenum - lines_before;
343
344                                         /* advance to the first entry in the circular buffer, and
345                                          * figure out the line number is of the first line in the
346                                          * buffer */
347                                         idx = curpos;
348                                         while (before_buf[idx] == NULL) {
349                                                 idx = (idx + 1) % lines_before;
350                                                 first_buf_entry_line_num++;
351                                         }
352
353                                         /* now print each line in the buffer, clearing them as we go */
354                                         while (before_buf[idx] != NULL) {
355                                                 print_line(before_buf[idx], before_buf_size[idx], first_buf_entry_line_num, '-');
356                                                 free(before_buf[idx]);
357                                                 before_buf[idx] = NULL;
358                                                 idx = (idx + 1) % lines_before;
359                                                 first_buf_entry_line_num++;
360                                         }
361                                 }
362
363                                 /* make a note that we need to print 'after' lines */
364                                 print_n_lines_after = lines_after;
365 #endif
366                                 if (option_mask32 & OPT_o) {
367                                         if (FGREP_FLAG) {
368                                                 /* -Fo just prints the pattern
369                                                  * (unless -v: -Fov doesnt print anything at all) */
370                                                 if (found)
371                                                         print_line(gl->pattern, strlen(gl->pattern), linenum, ':');
372                                         } else while (1) {
373                                                 char old = line[gl->matched_range.rm_eo];
374                                                 line[gl->matched_range.rm_eo] = '\0';
375                                                 print_line(line + gl->matched_range.rm_so,
376                                                                 gl->matched_range.rm_eo - gl->matched_range.rm_so,
377                                                                 linenum, ':');
378                                                 line[gl->matched_range.rm_eo] = old;
379 #if !ENABLE_EXTRA_COMPAT
380                                                 break;
381 #else
382                                                 if (re_search(&gl->compiled_regex, line, line_len,
383                                                                 gl->matched_range.rm_eo, line_len - gl->matched_range.rm_eo,
384                                                                 &gl->matched_range) < 0)
385                                                         break;
386 #endif
387                                         }
388                                 } else {
389                                         print_line(line, line_len, linenum, ':');
390                                 }
391                         }
392                 }
393 #if ENABLE_FEATURE_GREP_CONTEXT
394                 else { /* no match */
395                         /* if we need to print some context lines after the last match, do so */
396                         if (print_n_lines_after) {
397                                 print_line(line, strlen(line), linenum, '-');
398                                 print_n_lines_after--;
399                         } else if (lines_before) {
400                                 /* Add the line to the circular 'before' buffer */
401                                 free(before_buf[curpos]);
402                                 before_buf[curpos] = line;
403                                 USE_EXTRA_COMPAT(before_buf_size[curpos] = line_len;)
404                                 curpos = (curpos + 1) % lines_before;
405                                 /* avoid free(line) - we took the line */
406                                 line = NULL;
407                         }
408                 }
409
410 #endif /* ENABLE_FEATURE_GREP_CONTEXT */
411 #if !ENABLE_EXTRA_COMPAT
412                 free(line);
413 #endif
414                 /* Did we print all context after last requested match? */
415                 if ((option_mask32 & OPT_m)
416                  && !print_n_lines_after
417                  && nmatches == max_matches
418                 ) {
419                         break;
420                 }
421         } /* while (read line) */
422
423         /* special-case file post-processing for options where we don't print line
424          * matches, just filenames and possibly match counts */
425
426         /* grep -c: print [filename:]count, even if count is zero */
427         if (PRINT_MATCH_COUNTS) {
428                 if (print_filename)
429                         printf("%s:", cur_file);
430                 printf("%d\n", nmatches);
431         }
432
433         /* grep -L: print just the filename */
434         if (PRINT_FILES_WITHOUT_MATCHES) {
435                 /* nmatches is zero, no need to check it:
436                  * we return 1 early if we detected a match
437                  * and PRINT_FILES_WITHOUT_MATCHES is set */
438                 puts(cur_file);
439         }
440
441         return nmatches;
442 }
443
444 #if ENABLE_FEATURE_CLEAN_UP
445 #define new_grep_list_data(p, m) add_grep_list_data(p, m)
446 static char *add_grep_list_data(char *pattern, int flg_used_mem)
447 #else
448 #define new_grep_list_data(p, m) add_grep_list_data(p)
449 static char *add_grep_list_data(char *pattern)
450 #endif
451 {
452         grep_list_data_t *gl = xzalloc(sizeof(*gl));
453         gl->pattern = pattern;
454 #if ENABLE_FEATURE_CLEAN_UP
455         gl->flg_mem_alocated_compiled = flg_used_mem;
456 #else
457         /*gl->flg_mem_alocated_compiled = 0;*/
458 #endif
459         return (char *)gl;
460 }
461
462 static void load_regexes_from_file(llist_t *fopt)
463 {
464         char *line;
465         FILE *f;
466
467         while (fopt) {
468                 llist_t *cur = fopt;
469                 char *ffile = cur->data;
470
471                 fopt = cur->link;
472                 free(cur);
473                 f = xfopen_stdin(ffile);
474                 while ((line = xmalloc_fgetline(f)) != NULL) {
475                         llist_add_to(&pattern_head,
476                                 new_grep_list_data(line, ALLOCATED));
477                 }
478         }
479 }
480
481 static int FAST_FUNC file_action_grep(const char *filename,
482                         struct stat *statbuf UNUSED_PARAM,
483                         void* matched,
484                         int depth UNUSED_PARAM)
485 {
486         FILE *file = fopen_for_read(filename);
487         if (file == NULL) {
488                 if (!SUPPRESS_ERR_MSGS)
489                         bb_simple_perror_msg(filename);
490                 open_errors = 1;
491                 return 0;
492         }
493         cur_file = filename;
494         *(int*)matched += grep_file(file);
495         fclose(file);
496         return 1;
497 }
498
499 static int grep_dir(const char *dir)
500 {
501         int matched = 0;
502         recursive_action(dir,
503                 /* recurse=yes */ ACTION_RECURSE |
504                 /* followLinks=no */
505                 /* depthFirst=yes */ ACTION_DEPTHFIRST,
506                 /* fileAction= */ file_action_grep,
507                 /* dirAction= */ NULL,
508                 /* userData= */ &matched,
509                 /* depth= */ 0);
510         return matched;
511 }
512
513 int grep_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
514 int grep_main(int argc, char **argv)
515 {
516         FILE *file;
517         int matched;
518         llist_t *fopt = NULL;
519
520         /* do normal option parsing */
521 #if ENABLE_FEATURE_GREP_CONTEXT
522         int Copt;
523
524         /* -H unsets -h; -C unsets -A,-B; -e,-f are lists;
525          * -m,-A,-B,-C have numeric param */
526         opt_complementary = "H-h:C-AB:e::f::m+:A+:B+:C+";
527         getopt32(argv,
528                 OPTSTR_GREP,
529                 &pattern_head, &fopt, &max_matches,
530                 &lines_after, &lines_before, &Copt);
531
532         if (option_mask32 & OPT_C) {
533                 /* -C unsets prev -A and -B, but following -A or -B
534                    may override it */
535                 if (!(option_mask32 & OPT_A)) /* not overridden */
536                         lines_after = Copt;
537                 if (!(option_mask32 & OPT_B)) /* not overridden */
538                         lines_before = Copt;
539         }
540         /* sanity checks */
541         if (option_mask32 & (OPT_c|OPT_q|OPT_l|OPT_L)) {
542                 option_mask32 &= ~OPT_n;
543                 lines_before = 0;
544                 lines_after = 0;
545         } else if (lines_before > 0) {
546                 before_buf = xzalloc(lines_before * sizeof(before_buf[0]));
547                 USE_EXTRA_COMPAT(before_buf_size = xzalloc(lines_before * sizeof(before_buf_size[0]));)
548         }
549 #else
550         /* with auto sanity checks */
551         /* -H unsets -h; -c,-q or -l unset -n; -e,-f are lists; -m N */
552         opt_complementary = "H-h:c-n:q-n:l-n:e::f::m+";
553         getopt32(argv, OPTSTR_GREP,
554                 &pattern_head, &fopt, &max_matches);
555 #endif
556         invert_search = ((option_mask32 & OPT_v) != 0); /* 0 | 1 */
557
558         if (pattern_head != NULL) {
559                 /* convert char **argv to grep_list_data_t */
560                 llist_t *cur;
561
562                 for (cur = pattern_head; cur; cur = cur->link)
563                         cur->data = new_grep_list_data(cur->data, 0);
564         }
565         if (option_mask32 & OPT_f)
566                 load_regexes_from_file(fopt);
567
568         if (ENABLE_FEATURE_GREP_FGREP_ALIAS && applet_name[0] == 'f')
569                 option_mask32 |= OPT_F;
570
571 #if !ENABLE_EXTRA_COMPAT
572         if (!(option_mask32 & (OPT_o | OPT_w)))
573                 reflags = REG_NOSUB;
574 #endif
575
576         if (ENABLE_FEATURE_GREP_EGREP_ALIAS
577          && (applet_name[0] == 'e' || (option_mask32 & OPT_E))
578         ) {
579                 reflags |= REG_EXTENDED;
580         }
581 #if ENABLE_EXTRA_COMPAT
582         else {
583                 reflags = RE_SYNTAX_GREP;
584         }
585 #endif
586
587         if (option_mask32 & OPT_i) {
588 #if !ENABLE_EXTRA_COMPAT
589                 reflags |= REG_ICASE;
590 #else
591                 int i;
592                 case_fold = xmalloc(256);
593                 for (i = 0; i < 256; i++)
594                         case_fold[i] = (unsigned char)i;
595                 for (i = 'a'; i <= 'z'; i++)
596                         case_fold[i] = (unsigned char)(i - ('a' - 'A'));
597 #endif
598         }
599
600         argv += optind;
601         argc -= optind;
602
603         /* if we didn't get a pattern from -e and no command file was specified,
604          * first parameter should be the pattern. no pattern, no worky */
605         if (pattern_head == NULL) {
606                 char *pattern;
607                 if (*argv == NULL)
608                         bb_show_usage();
609                 pattern = new_grep_list_data(*argv++, 0);
610                 llist_add_to(&pattern_head, pattern);
611                 argc--;
612         }
613
614         /* argv[0..(argc-1)] should be names of file to grep through. If
615          * there is more than one file to grep, we will print the filenames. */
616         if (argc > 1)
617                 print_filename = 1;
618         /* -H / -h of course override */
619         if (option_mask32 & OPT_H)
620                 print_filename = 1;
621         if (option_mask32 & OPT_h)
622                 print_filename = 0;
623
624         /* If no files were specified, or '-' was specified, take input from
625          * stdin. Otherwise, we grep through all the files specified. */
626         matched = 0;
627         do {
628                 cur_file = *argv++;
629                 file = stdin;
630                 if (!cur_file || LONE_DASH(cur_file)) {
631                         cur_file = "(standard input)";
632                 } else {
633                         if (option_mask32 & OPT_r) {
634                                 struct stat st;
635                                 if (stat(cur_file, &st) == 0 && S_ISDIR(st.st_mode)) {
636                                         if (!(option_mask32 & OPT_h))
637                                                 print_filename = 1;
638                                         matched += grep_dir(cur_file);
639                                         goto grep_done;
640                                 }
641                         }
642                         /* else: fopen(dir) will succeed, but reading won't */
643                         file = fopen_for_read(cur_file);
644                         if (file == NULL) {
645                                 if (!SUPPRESS_ERR_MSGS)
646                                         bb_simple_perror_msg(cur_file);
647                                 open_errors = 1;
648                                 continue;
649                         }
650                 }
651                 matched += grep_file(file);
652                 fclose_if_not_stdin(file);
653  grep_done: ;
654         } while (--argc > 0);
655
656         /* destroy all the elments in the pattern list */
657         if (ENABLE_FEATURE_CLEAN_UP) {
658                 while (pattern_head) {
659                         llist_t *pattern_head_ptr = pattern_head;
660                         grep_list_data_t *gl = (grep_list_data_t *)pattern_head_ptr->data;
661
662                         pattern_head = pattern_head->link;
663                         if (gl->flg_mem_alocated_compiled & ALLOCATED)
664                                 free(gl->pattern);
665                         if (gl->flg_mem_alocated_compiled & COMPILED)
666                                 regfree(&gl->compiled_regex);
667                         free(gl);
668                         free(pattern_head_ptr);
669                 }
670         }
671         /* 0 = success, 1 = failed, 2 = error */
672         if (open_errors)
673                 return 2;
674         return !matched; /* invert return value: 0 = success, 1 = failed */
675 }