diff options
Diffstat (limited to 'grep.c')
| -rw-r--r-- | grep.c | 358 |
1 files changed, 0 insertions, 358 deletions
@@ -1,358 +0,0 @@ -/* - * Mini grep implementation for busybox using libc regex. - * - * Copyright (C) 1999,2000,2001 by Lineo, inc. - * Written by Mark Whitley <markw@lineo.com>, <markw@codepoet.org> - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA - * - */ - -#include <stdio.h> -#include <stdlib.h> -#include <getopt.h> -#include <regex.h> -#include <string.h> /* for strerror() */ -#include <errno.h> -#include "busybox.h" - - -extern int optind; /* in unistd.h */ -extern void xregcomp(regex_t *preg, const char *regex, int cflags); /* in busybox.h */ - -/* options */ -static int reflags = REG_NOSUB; -static int print_filename = 0; -static int print_line_num = 0; -static int print_match_counts = 0; -static int be_quiet = 0; -static int invert_search = 0; -static int suppress_err_msgs = 0; -static int print_files_with_matches = 0; - -#ifdef BB_FEATURE_GREP_CONTEXT -extern char *optarg; /* in getopt.h */ -static int lines_before = 0; -static int lines_after = 0; -static char **before_buf = NULL; -static int last_line_printed = 0; -#endif /* BB_FEATURE_GREP_CONTEXT */ - -/* globals used internally */ -static regex_t *regexes = NULL; /* growable array of compiled regular expressions */ -static int nregexes = 0; /* number of elements in above arrary */ -static int matched; /* keeps track of whether we ever matched */ -static char *cur_file = NULL; /* the current file we are reading */ - - -static void print_line(const char *line, int linenum, char decoration) -{ -#ifdef BB_FEATURE_GREP_CONTEXT - /* possibly print the little '--' seperator */ - if ((lines_before || lines_after) && last_line_printed && - last_line_printed < linenum - 1) { - puts("--"); - } - last_line_printed = linenum; -#endif - if (print_filename) - printf("%s%c", cur_file, decoration); - if (print_line_num) - printf("%i%c", linenum, decoration); - puts(line); -} - - -static void grep_file(FILE *file) -{ - char *line = NULL; - int ret; - int linenum = 0; - int nmatches = 0; - int i; -#ifdef BB_FEATURE_GREP_CONTEXT - int print_n_lines_after = 0; - int curpos = 0; /* track where we are in the circular 'before' buffer */ - int idx = 0; /* used for iteration through the circular buffer */ -#endif /* BB_FEATURE_GREP_CONTEXT */ - - while ((line = get_line_from_file(file)) != NULL) { - chomp(line); - linenum++; - - for (i = 0; i < nregexes; i++) { - /* - * test for a postitive-assertion match (regexec returns success (0) - * and the user did not specify invert search), or a negative-assertion - * match (regexec returns failure (REG_NOMATCH) and the user specified - * invert search) - */ - ret = regexec(®exes[i], line, 0, NULL, 0); - if ((ret == 0 && !invert_search) || (ret == REG_NOMATCH && invert_search)) { - - /* if we found a match but were told to be quiet, stop here and - * return success */ - if (be_quiet) - exit(0); - - /* keep track of matches */ - nmatches++; - - /* if we're just printing filenames, we stop after the first match */ - if (print_files_with_matches) - break; - - /* print the matched line */ - if (print_match_counts == 0) { -#ifdef BB_FEATURE_GREP_CONTEXT - int prevpos = (curpos == 0) ? lines_before - 1 : curpos - 1; - - /* if we were told to print 'before' lines and there is at least - * one line in the circular buffer, print them */ - if (lines_before && before_buf[prevpos] != NULL) { - int first_buf_entry_line_num = linenum - lines_before; - - /* advance to the first entry in the circular buffer, and - * figure out the line number is of the first line in the - * buffer */ - idx = curpos; - while (before_buf[idx] == NULL) { - idx = (idx + 1) % lines_before; - first_buf_entry_line_num++; - } - - /* now print each line in the buffer, clearing them as we go */ - while (before_buf[idx] != NULL) { - print_line(before_buf[idx], first_buf_entry_line_num, '-'); - free(before_buf[idx]); - before_buf[idx] = NULL; - idx = (idx + 1) % lines_before; - first_buf_entry_line_num++; - } - } - - /* make a note that we need to print 'after' lines */ - print_n_lines_after = lines_after; -#endif /* BB_FEATURE_GREP_CONTEXT */ - print_line(line, linenum, ':'); - } - } -#ifdef BB_FEATURE_GREP_CONTEXT - else { /* no match */ - /* Add the line to the circular 'before' buffer */ - if(lines_before) { - if(before_buf[curpos]) - free(before_buf[curpos]); - before_buf[curpos] = strdup(line); - curpos = (curpos + 1) % lines_before; - } - } - - /* if we need to print some context lines after the last match, do so */ - if (print_n_lines_after && (last_line_printed != linenum)) { - print_line(line, linenum, '-'); - print_n_lines_after--; - } -#endif /* BB_FEATURE_GREP_CONTEXT */ - } /* for */ - free(line); - } - - - /* special-case file post-processing for options where we don't print line - * matches, just filenames and possibly match counts */ - - /* grep -c: print [filename:]count, even if count is zero */ - if (print_match_counts) { - if (print_filename) - printf("%s:", cur_file); - if (print_files_with_matches && nmatches > 0) - printf("1\n"); - else - printf("%d\n", nmatches); - } - - /* grep -l: print just the filename, but only if we grepped the line in the file */ - if (print_files_with_matches && nmatches > 0) { - puts(cur_file); - } - - - /* remember if we matched */ - if (nmatches != 0) - matched = 1; -} - - -static void add_regex(const char *restr) -{ - regexes = xrealloc(regexes, sizeof(regex_t) * (++nregexes)); - xregcomp(®exes[nregexes-1], restr, reflags); -} - - -static void load_regexes_from_file(const char *filename) -{ - char *line; - FILE *f = xfopen(filename, "r"); - while ((line = get_line_from_file(f)) != NULL) { - chomp(line); - add_regex(line); - free(line); - } -} - - -#ifdef BB_FEATURE_CLEAN_UP -static void destroy_regexes() -{ - if (regexes == NULL) - return; - - /* destroy all the elments in the array */ - while (--nregexes >= 0) { - regfree(®exes[nregexes]); - free(®exes[nregexes]); - } -} -#endif - - -extern int grep_main(int argc, char **argv) -{ - int opt; -#ifdef BB_FEATURE_GREP_CONTEXT - char *junk; -#endif - -#ifdef BB_FEATURE_CLEAN_UP - /* destroy command strings on exit */ - if (atexit(destroy_regexes) == -1) - perror_msg_and_die("atexit"); -#endif - - /* do normal option parsing */ - while ((opt = getopt(argc, argv, "iHhlnqvsce:f:" -#ifdef BB_FEATURE_GREP_CONTEXT -"A:B:C:" -#endif -)) > 0) { - switch (opt) { - case 'i': - reflags |= REG_ICASE; - break; - case 'l': - print_files_with_matches++; - break; - case 'H': - print_filename++; - break; - case 'h': - print_filename--; - break; - case 'n': - print_line_num++; - break; - case 'q': - be_quiet++; - break; - case 'v': - invert_search++; - break; - case 's': - suppress_err_msgs++; - break; - case 'c': - print_match_counts++; - break; - case 'e': - add_regex(optarg); - break; - case 'f': - load_regexes_from_file(optarg); - break; -#ifdef BB_FEATURE_GREP_CONTEXT - case 'A': - lines_after = strtoul(optarg, &junk, 10); - if(*junk != '\0') - error_msg_and_die("invalid context length argument"); - break; - case 'B': - lines_before = strtoul(optarg, &junk, 10); - if(*junk != '\0') - error_msg_and_die("invalid context length argument"); - before_buf = (char **)calloc(lines_before, sizeof(char *)); - break; - case 'C': - lines_after = lines_before = strtoul(optarg, &junk, 10); - if(*junk != '\0') - error_msg_and_die("invalid context length argument"); - before_buf = (char **)calloc(lines_before, sizeof(char *)); - break; -#endif /* BB_FEATURE_GREP_CONTEXT */ - default: - show_usage(); - } - } - - /* if we didn't get a pattern from a -e and no command file was specified, - * argv[optind] should be the pattern. no pattern, no worky */ - if (nregexes == 0) { - if (argv[optind] == NULL) - show_usage(); - else { - add_regex(argv[optind]); - optind++; - } - } - - /* sanity checks */ - if (print_match_counts || be_quiet || print_files_with_matches) { - print_line_num = 0; -#ifdef BB_FEATURE_GREP_CONTEXT - lines_before = 0; - lines_after = 0; -#endif - } - - /* argv[(optind)..(argc-1)] should be names of file to grep through. If - * there is more than one file to grep, we will print the filenames */ - if ((argc-1) - (optind) > 0) - print_filename++; - - /* If no files were specified, or '-' was specified, take input from - * stdin. Otherwise, we grep through all the files specified. */ - if (argv[optind] == NULL || (strcmp(argv[optind], "-") == 0)) { - grep_file(stdin); - } - else { - int i; - FILE *file; - for (i = optind; i < argc; i++) { - cur_file = argv[i]; - file = fopen(cur_file, "r"); - if (file == NULL) { - if (!suppress_err_msgs) - perror_msg("%s", cur_file); - } - else { - grep_file(file); - fclose(file); - } - } - } - - return !matched; /* invert return value 0 = success, 1 = failed */ -} |