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authorMark Whitley2000-06-28 22:00:26 +0000
committerMark Whitley2000-06-28 22:00:26 +0000
commitd37218941c37795cc8e96ddb3312d83fb2269d5a (patch)
treef0b2aa0f49da8e0d4fb76a81a491e1d1ee5c4a05 /findutils/grep.c
parent268b8c4f387b9019bbb3591fb07403925d55d0c5 (diff)
downloadbusybox-d37218941c37795cc8e96ddb3312d83fb2269d5a.zip
busybox-d37218941c37795cc8e96ddb3312d83fb2269d5a.tar.gz
Brand, spankin', new grep that uses libc regex routines instead of the
hand-rolled ones. Sed still needs to be replaced and then the regexp stuff can be axed.
Diffstat (limited to 'findutils/grep.c')
-rw-r--r--findutils/grep.c255
1 files changed, 155 insertions, 100 deletions
diff --git a/findutils/grep.c b/findutils/grep.c
index 0e495ff..aca469e 100644
--- a/findutils/grep.c
+++ b/findutils/grep.c
@@ -1,10 +1,8 @@
-/* vi: set sw=4 ts=4: */
/*
- * Mini grep implementation for busybox
- *
+ * Mini grep implementation for busybox using libc regex.
*
* Copyright (C) 1999,2000 by Lineo, inc.
- * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>
+ * Written by Mark Whitley <markw@lineo.com>, <markw@enol.com>
*
* 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
@@ -22,149 +20,206 @@
*
*/
-/*
- 18-Dec-1999 Konstantin Boldyshev <konst@voshod.com>
-
- + -q option (be quiet)
- + exit code depending on grep result (TRUE or FALSE)
- (useful for scripts)
-*/
-
-#include "internal.h"
-#include "regexp.h"
#include <stdio.h>
-#include <dirent.h>
+#include <stdlib.h>
+#include <unistd.h> /* for getopt() */
+#include <regex.h>
+#include <string.h> /* for strerror() */
#include <errno.h>
-#include <fcntl.h>
-#include <signal.h>
-#include <time.h>
-#include <ctype.h>
-#define BB_DECLARE_EXTERN
-#define bb_need_too_few_args
-#include "messages.c"
+#include "internal.h"
+
+extern int optind; /* in unistd.h */
+extern int errno; /* for use with strerror() */
static const char grep_usage[] =
- "grep [OPTIONS]... PATTERN [FILE]...\n"
+ "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\n"
-#if defined BB_REGEXP
- "This version of grep matches full regular expressions.\n";
-#else
- "This version of grep matches strings (not regular expressions).\n"
-#endif
+ "\t-v\tselect non-matching lines\n"
+ "\t-s\tsuppress file open/read error messages\n\n"
#endif
;
-static int match = FALSE, beQuiet = FALSE;
+static const int GROWBY = 80; /* how large we will grow strings by */
+
+/* options */
+static int ignore_case = 0;
+static int print_filename = 0;
+static int print_line_num = 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 nmatches = 0; /* keeps track of the number of matches */
+static char *cur_file = NULL; /* the current file we are reading */
+
-static void do_grep(FILE * fp, char *needle, char *fileName, int tellName,
- int ignoreCase, int tellLine, int invertSearch)
+/* 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)
{
- long line = 0;
- char *haystack;
- int truth = !invertSearch;
+ 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;
+ }
+
+ if (idx == 0)
+ return NULL;
+
+ linebuf[idx] = 0;
+ return linebuf;
+}
+
+static void print_matched_line(char *line, int linenum)
+{
+ if (print_filename)
+ printf("%s:", cur_file);
+ if (print_line_num)
+ printf("%i:", linenum);
+
+ printf("%s", line);
+}
- while ((haystack = cstring_lineFromFile(fp))) {
- line++;
- if (find_match(haystack, needle, ignoreCase) == truth) {
- if (tellName == TRUE)
- printf("%s:", fileName);
+static void grep_file(FILE *file)
+{
+ char *line = NULL;
+ int ret;
+ int linenum = 0;
+
+ while ((line = get_line_from_file(file)) != NULL) {
+ linenum++;
+ ret = regexec(&regex, 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(&regex);
+ exit(0);
+ }
- if (tellLine == TRUE)
- printf("%ld:", line);
+ nmatches++;
- if (beQuiet == FALSE)
- fputs(haystack, stdout);
+ print_matched_line(line, linenum);
- match = TRUE;
+ } else if (ret == REG_NOMATCH && invert_search) {
+ print_matched_line(line, linenum);
}
- free(haystack);
+
+ free(line);
}
}
-
extern int grep_main(int argc, char **argv)
{
- FILE *fp;
- char *needle;
- char *fileName;
- int tellName = TRUE;
- int ignoreCase = FALSE;
- int tellLine = FALSE;
- int invertSearch = FALSE;
-
- if (argc < 1) {
+ int opt;
+ int reflags;
+ int ret;
+
+ /* do special-case option parsing */
+ if (argv[1] && (strcmp(argv[1], "--help") == 0))
usage(grep_usage);
- }
- argv++;
- while (--argc >= 0 && *argv && (**argv == '-')) {
- while (*++(*argv)) {
- switch (**argv) {
+ /* do normal option parsing */
+ while ((opt = getopt(argc, argv, "iHhnqvs")) > 0) {
+ switch (opt) {
case 'i':
- ignoreCase = TRUE;
+ ignore_case++;
+ break;
+ case 'H':
+ print_filename++;
break;
-
case 'h':
- tellName = FALSE;
+ print_filename--;
break;
-
case 'n':
- tellLine = TRUE;
+ print_line_num++;
break;
-
case 'q':
- beQuiet = TRUE;
+ be_quiet++;
break;
-
case 'v':
- invertSearch = TRUE;
+ invert_search++;
+ break;
+ case 's':
+ suppress_err_msgs++;
break;
-
- default:
- usage(grep_usage);
- }
}
- argv++;
}
- if (argc == 0 || *argv == NULL) {
- fatalError(too_few_args, "grep");
+ /* argv[optind] should be the regex pattern; no pattern, no worky */
+ if (argv[optind] == NULL)
+ usage(grep_usage);
+
+ /* compile the regular expression */
+ reflags = REG_NOSUB; /* we're not going to mess with sub-expressions */
+ if (ignore_case)
+ reflags |= REG_ICASE;
+ if ((ret = regcomp(&regex, argv[optind], reflags)) != 0) {
+ int errmsgsz = regerror(ret, &regex, NULL, 0);
+ char *errmsg = malloc(errmsgsz);
+ if (errmsg == NULL) {
+ fprintf(stderr, "grep: memory error\n");
+ regfree(&regex);
+ exit(1);
+ }
+ regerror(ret, &regex, errmsg, errmsgsz);
+ fprintf(stderr, "grep: %s\n", errmsg);
+ free(errmsg);
+ regfree(&regex);
+ exit(1);
}
- needle = *argv++;
- argc--;
+ /* 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 (argc == 0) {
- do_grep(stdin, needle, "stdin", FALSE, ignoreCase, tellLine, invertSearch);
+ /* If no files were specified, take input from stdin. Otherwise, we grep
+ * through all the files specified. */
+ if (argv[optind+1] == NULL) {
+ grep_file(stdin);
} else {
- /* Never print the filename for just one file */
- if (argc == 1)
- tellName = FALSE;
- while (argc-- > 0) {
- fileName = *argv++;
-
- fp = fopen(fileName, "r");
- if (fp == NULL) {
- perror(fileName);
- continue;
+ 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)
+ fprintf(stderr, "grep: %s: %s\n", cur_file, strerror(errno));
+ } else {
+ grep_file(file);
+ fclose(file);
}
-
- do_grep(fp, needle, fileName, tellName, ignoreCase, tellLine, invertSearch);
-
- if (ferror(fp))
- perror(fileName);
- fclose(fp);
}
}
- return(match);
-}
+ regfree(&regex);
-/* END CODE */
+ if (nmatches == 0)
+ return 1;
+
+ return 0;
+}