/*
* 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 <stdio.h>
#include <stdlib.h>
-#include <unistd.h> /* for getopt() */
+#include <getopt.h>
#include <regex.h>
#include <string.h> /* for strerror() */
#include <errno.h>
-#include "internal.h"
+#include "busybox.h"
+
extern int optind; /* in unistd.h */
extern int errno; /* for use with strerror() */
-
-static const char grep_usage[] =
- "grep [-ihHnqvs] pattern [files...]\n"
-#ifndef BB_FEATURE_TRIVIAL_HELP
- "\nSearch for PATTERN in each FILE or standard input.\n\n"
- "OPTIONS:\n"
- "\t-H\tprefix output lines with filename where match was found\n"
- "\t-h\tsuppress the prefixing filename on output\n"
- "\t-i\tignore case distinctions\n"
- "\t-n\tprint line number with output lines\n"
- "\t-q\tbe quiet. Returns 0 if result was found, 1 otherwise\n"
- "\t-v\tselect non-matching lines\n"
- "\t-s\tsuppress file open/read error messages\n\n"
-#endif
- ;
-
-static const int GROWBY = 80; /* how large we will grow strings by */
+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;
+static int files_that_match = 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 */
+/* globals used internally */
static regex_t regex; /* storage space for compiled regular expression */
-static int nmatches = 0; /* keeps track of the number of matches */
+static int matched; /* keeps track of whether we ever matched */
static char *cur_file = NULL; /* the current file we are reading */
-
-/* This returns a malloc'ed char * which must be stored and free'ed */
-/* XXX: This function should probably go in a 'common'/'util'/'misc' file
- * somewhere so it can be used by other folks. */
-static char *get_line_from_file(FILE *file)
+static void print_line(const char *line, int linenum, char decoration)
{
- int ch;
- int idx = 0;
- char *linebuf = NULL;
- int linebufsz = 0;
-
- while (1) {
- ch = fgetc(file);
- if (ch == EOF)
- break;
- /* grow the line buffer as necessary */
- if (idx > linebufsz-1)
- linebuf = realloc(linebuf, linebufsz += GROWBY);
- linebuf[idx++] = (char)ch;
- if ((char)ch == '\n')
- break;
+#ifdef BB_FEATURE_GREP_CONTEXT
+ /* possibly print the little '--' seperator */
+ if (last_line_printed && last_line_printed < linenum - 1) {
+ puts("--");
}
-
- if (idx == 0)
- return NULL;
-
- linebuf[idx] = 0;
- return linebuf;
-}
-
-static void print_matched_line(char *line, int linenum)
-{
+ 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("%s", line);
+ 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) { /* match */
+ 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 */
exit(0);
}
+ /* otherwise, keep track of matches and print the matched line */
nmatches++;
+ if (print_count_only==0 && files_that_match==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;
- print_matched_line(line, linenum);
+ /* 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++;
+ }
- } else if (ret == REG_NOMATCH && invert_search) {
- print_matched_line(line, linenum);
+ /* 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 (files_that_match) {
+ if (nmatches > 0) {
+ printf("%s", cur_file);
+ if (nmatches)
+ printf(":%d", nmatches);
+ printf("\n");
+ }
+ } else 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;
- int ret;
-
- /* do special-case option parsing */
- if (argv[1] && (strcmp(argv[1], "--help") == 0))
- usage(grep_usage);
+#ifdef BB_FEATURE_GREP_CONTEXT
+ char *junk;
+#endif
/* do normal option parsing */
- while ((opt = getopt(argc, argv, "iHhnqvs")) > 0) {
+ while ((opt = getopt(argc, argv, "iHhlnqvsc"
+#ifdef BB_FEATURE_GREP_CONTEXT
+"A:B:C:"
+#endif
+)) > 0) {
switch (opt) {
case 'i':
ignore_case++;
break;
+ case 'l':
+ files_that_match++;
+ break;
case 'H':
print_filename++;
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 */
+ default:
+ show_usage();
}
}
/* argv[optind] should be the regex pattern; no pattern, no worky */
if (argv[optind] == NULL)
- usage(grep_usage);
+ show_usage();
+
+ /* sanity check */
+ if (print_count_only || be_quiet || files_that_match) {
+ print_line_num = 0;
+#ifdef BB_FEATURE_GREP_CONTEXT
+ lines_before = 0;
+ lines_after = 0;
+#endif
+ }
- /* compile the regular expression */
- reflags = REG_NOSUB; /* we're not going to mess with sub-expressions */
+ /* 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;
- if ((ret = regcomp(®ex, argv[optind], reflags)) != 0) {
- int errmsgsz = regerror(ret, ®ex, NULL, 0);
- char *errmsg = malloc(errmsgsz);
- if (errmsg == NULL) {
- fprintf(stderr, "grep: memory error\n");
- regfree(®ex);
- exit(1);
- }
- regerror(ret, ®ex, errmsg, errmsgsz);
- fprintf(stderr, "grep: %s\n", errmsg);
- free(errmsg);
- regfree(®ex);
- exit(1);
- }
+ 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, take input from stdin. Otherwise, we grep
- * through all the files specified. */
- if (argv[optind+1] == NULL) {
+ /* 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 {
+ }
+ else {
int i;
FILE *file;
for (i = optind + 1; i < argc; i++) {
file = fopen(cur_file, "r");
if (file == NULL) {
if (!suppress_err_msgs)
- fprintf(stderr, "grep: %s: %s\n", cur_file, strerror(errno));
- } else {
+ perror_msg("%s", cur_file);
+ }
+ else {
grep_file(file);
fclose(file);
}
regfree(®ex);
- if (nmatches == 0)
- return 1;
-
- return 0;
+ return !matched; /* invert return value 0 = success, 1 = failed */
}