/*
* Mini grep implementation for busybox using libc regex.
*
- * Copyright (C) 1999,2000 by Lineo, inc.
- * Written by Mark Whitley <markw@lineo.com>, <markw@enol.com>
+ * 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
#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;
-
-/* globals */
-static regex_t regex; /* storage space for compiled regular expression */
+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_matched_line(char *line, int linenum)
+static void print_line(const char *line, int linenum, char decoration)
{
- if (print_count_only)
- return;
-
+#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:", cur_file);
+ printf("%s%c", cur_file, decoration);
if (print_line_num)
- printf("%i:", linenum);
-
+ 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) {
- if (line[strlen(line)-1] == '\n')
- line[strlen(line)-1] = '\0';
+ chomp(line);
linenum++;
- ret = regexec(®ex, line, 0, NULL, 0);
- if (ret == 0 && !invert_search) { /* match */
-
- /* if we found a match but were told to be quiet, stop here and
- * return success */
- if (be_quiet) {
- regfree(®ex);
- exit(0);
- }
- nmatches++;
- print_matched_line(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)) {
- }
- else if (ret == REG_NOMATCH && invert_search) {
- nmatches++;
- print_matched_line(line, linenum);
- }
+ /* 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 post processing */
- if (print_count_only) {
+
+ /* 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);
- printf("%i\n", nmatches);
+ 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);
}
- /* record if we matched */
+
+ /* 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;
- int reflags;
+#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, "iHhnqvsc")) > 0) {
+ while ((opt = getopt(argc, argv, "iHhlnqvsce:f:"
+#ifdef BB_FEATURE_GREP_CONTEXT
+"A:B:C:"
+#endif
+)) > 0) {
switch (opt) {
case 'i':
- ignore_case++;
+ reflags |= REG_ICASE;
+ break;
+ case 'l':
+ print_files_with_matches++;
break;
case 'H':
print_filename++;
suppress_err_msgs++;
break;
case 'c':
- print_count_only++;
+ 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();
}
}
- /* argv[optind] should be the regex pattern; no pattern, no worky */
- if (argv[optind] == NULL)
- usage(grep_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++;
+ }
+ }
- /* 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);
+ /* 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+1)..(argc-1)] should be names of file to grep through. If
+ /* 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+1) > 0)
+ 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+1] == NULL || (strcmp(argv[optind+1], "-") == 0)) {
+ if (argv[optind] == NULL || (strcmp(argv[optind], "-") == 0)) {
grep_file(stdin);
}
else {
int i;
FILE *file;
- for (i = optind + 1; i < argc; i++) {
+ for (i = optind; i < argc; i++) {
cur_file = argv[i];
file = fopen(cur_file, "r");
if (file == NULL) {
if (!suppress_err_msgs)
- errorMsg("%s: %s\n", cur_file, strerror(errno));
+ perror_msg("%s", cur_file);
}
else {
grep_file(file);
}
}
- regfree(®ex);
-
- if (!matched)
- return 1;
-
- return 0;
+ return !matched; /* invert return value 0 = success, 1 = failed */
}