/* * 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 int errno; /* for use with strerror() */ extern void xregcomp(regex_t *preg, const char *regex, int cflags); /* in busybox.h */ /* options */ static int ignore_case = 0; static int print_filename = 0; static int print_line_num = 0; static int print_count_only = 0; static int be_quiet = 0; static int invert_search = 0; static int suppress_err_msgs = 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 regex; /* storage space for compiled regular expression */ 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 (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; #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++; /* * 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(®ex, 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) { regfree(®ex); exit(0); } /* otherwise, keep track of matches and print the matched line */ nmatches++; if (!print_count_only) { #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 */ free(line); } /* special-case post processing */ if (print_count_only) { if (print_filename) printf("%s:", cur_file); printf("%i\n", nmatches); } /* remember if we matched */ if (nmatches != 0) matched = 1; } extern int grep_main(int argc, char **argv) { int opt; int reflags; #ifdef BB_FEATURE_GREP_CONTEXT char *junk; #endif /* do normal option parsing */ while ((opt = getopt(argc, argv, "iHhnqvsc" #ifdef BB_FEATURE_GREP_CONTEXT "A:B:C:" #endif )) > 0) { switch (opt) { case 'i': ignore_case++; 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_count_only++; 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 */ } } /* argv[optind] should be the regex pattern; no pattern, no worky */ if (argv[optind] == NULL) show_usage(); /* sanity check */ if (print_count_only || be_quiet) { print_line_num = 0; #ifdef BB_FEATURE_GREP_CONTEXT lines_before = 0; lines_after = 0; #endif } /* compile the regular expression * we're not going to mess with sub-expressions, and we need to * treat newlines right. */ reflags = REG_NOSUB; if (ignore_case) reflags |= REG_ICASE; xregcomp(®ex, argv[optind], reflags); /* argv[(optind+1)..(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+1) > 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+1] == NULL || (strcmp(argv[optind+1], "-") == 0)) { grep_file(stdin); } else { int i; FILE *file; for (i = optind + 1; 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); } } } regfree(®ex); return !matched; /* invert return value 0 = success, 1 = failed */ }