2 * Mini grep implementation for busybox using libc regex.
4 * Copyright (C) 1999,2000,2001 by Lineo, inc.
5 * Written by Mark Whitley <markw@lineo.com>, <markw@codepoet.org>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
27 #include <string.h> /* for strerror() */
32 extern int optind; /* in unistd.h */
33 extern int errno; /* for use with strerror() */
34 extern void xregcomp(regex_t *preg, const char *regex, int cflags); /* in busybox.h */
37 static int ignore_case = 0;
38 static int print_filename = 0;
39 static int print_line_num = 0;
40 static int print_count_only = 0;
41 static int be_quiet = 0;
42 static int invert_search = 0;
43 static int suppress_err_msgs = 0;
45 #ifdef BB_FEATURE_GREP_CONTEXT
46 extern char *optarg; /* in getopt.h */
47 static int lines_before = 0;
48 static int lines_after = 0;
49 static char **before_buf = NULL;
50 static int last_line_printed = 0;
51 #endif /* BB_FEATURE_GREP_CONTEXT */
53 /* globals used internally */
54 static regex_t regex; /* storage space for compiled regular expression */
55 static int matched; /* keeps track of whether we ever matched */
56 static char *cur_file = NULL; /* the current file we are reading */
58 static void print_line(const char *line, int linenum, char decoration)
60 #ifdef BB_FEATURE_GREP_CONTEXT
61 /* possibly print the little '--' seperator */
62 if (last_line_printed && last_line_printed < linenum - 1) {
65 last_line_printed = linenum;
68 printf("%s%c", cur_file, decoration);
70 printf("%i%c", linenum, decoration);
74 static void grep_file(FILE *file)
80 #ifdef BB_FEATURE_GREP_CONTEXT
81 int print_n_lines_after = 0;
82 int curpos = 0; /* track where we are in the circular 'before' buffer */
83 int idx = 0; /* used for iteration through the circular buffer */
84 #endif /* BB_FEATURE_GREP_CONTEXT */
86 while ((line = get_line_from_file(file)) != NULL) {
91 * test for a postitive-assertion match (regexec returns success (0)
92 * and the user did not specify invert search), or a negative-assertion
93 * match (regexec returns failure (REG_NOMATCH) and the user specified
96 ret = regexec(®ex, line, 0, NULL, 0);
97 if ((ret == 0 && !invert_search) || (ret == REG_NOMATCH && invert_search)) {
99 /* if we found a match but were told to be quiet, stop here and
106 /* otherwise, keep track of matches and print the matched line */
108 if (!print_count_only) {
109 #ifdef BB_FEATURE_GREP_CONTEXT
110 int prevpos = (curpos == 0) ? lines_before - 1 : curpos - 1;
112 /* if we were told to print 'before' lines and there is at least
113 * one line in the circular buffer, print them */
114 if (lines_before && before_buf[prevpos] != NULL)
116 int first_buf_entry_line_num = linenum - lines_before;
118 /* advance to the first entry in the circular buffer, and
119 * figure out the line number is of the first line in the
122 while (before_buf[idx] == NULL) {
123 idx = (idx + 1) % lines_before;
124 first_buf_entry_line_num++;
127 /* now print each line in the buffer, clearing them as we go */
128 while (before_buf[idx] != NULL) {
129 print_line(before_buf[idx], first_buf_entry_line_num, '-');
130 free(before_buf[idx]);
131 before_buf[idx] = NULL;
132 idx = (idx + 1) % lines_before;
133 first_buf_entry_line_num++;
138 /* make a note that we need to print 'after' lines */
139 print_n_lines_after = lines_after;
140 #endif /* BB_FEATURE_GREP_CONTEXT */
141 print_line(line, linenum, ':');
144 #ifdef BB_FEATURE_GREP_CONTEXT
145 else { /* no match */
146 /* Add the line to the circular 'before' buffer */
149 if(before_buf[curpos])
150 free(before_buf[curpos]);
151 before_buf[curpos] = strdup(line);
152 curpos = (curpos + 1) % lines_before;
156 /* if we need to print some context lines after the last match, do so */
157 if (print_n_lines_after && (last_line_printed != linenum)) {
158 print_line(line, linenum, '-');
159 print_n_lines_after--;
161 #endif /* BB_FEATURE_GREP_CONTEXT */
165 /* special-case post processing */
166 if (print_count_only) {
168 printf("%s:", cur_file);
169 printf("%i\n", nmatches);
172 /* remember if we matched */
177 extern int grep_main(int argc, char **argv)
181 #ifdef BB_FEATURE_GREP_CONTEXT
185 /* do normal option parsing */
186 while ((opt = getopt(argc, argv, "iHhnqvsc"
187 #ifdef BB_FEATURE_GREP_CONTEXT
216 #ifdef BB_FEATURE_GREP_CONTEXT
218 lines_after = strtoul(optarg, &junk, 10);
220 error_msg_and_die("invalid context length argument");
223 lines_before = strtoul(optarg, &junk, 10);
225 error_msg_and_die("invalid context length argument");
226 before_buf = (char **)calloc(lines_before, sizeof(char *));
229 lines_after = lines_before = strtoul(optarg, &junk, 10);
231 error_msg_and_die("invalid context length argument");
232 before_buf = (char **)calloc(lines_before, sizeof(char *));
234 #endif /* BB_FEATURE_GREP_CONTEXT */
240 /* argv[optind] should be the regex pattern; no pattern, no worky */
241 if (argv[optind] == NULL)
245 if (print_count_only || be_quiet) {
247 #ifdef BB_FEATURE_GREP_CONTEXT
253 /* compile the regular expression
254 * we're not going to mess with sub-expressions, and we need to
255 * treat newlines right. */
258 reflags |= REG_ICASE;
259 xregcomp(®ex, argv[optind], reflags);
261 /* argv[(optind+1)..(argc-1)] should be names of file to grep through. If
262 * there is more than one file to grep, we will print the filenames */
263 if ((argc-1) - (optind+1) > 0)
266 /* If no files were specified, or '-' was specified, take input from
267 * stdin. Otherwise, we grep through all the files specified. */
268 if (argv[optind+1] == NULL || (strcmp(argv[optind+1], "-") == 0)) {
274 for (i = optind + 1; i < argc; i++) {
276 file = fopen(cur_file, "r");
278 if (!suppress_err_msgs)
279 perror_msg("%s", cur_file);
290 return !matched; /* invert return value 0 = success, 1 = failed */