utils/src/strings.c

131 lines
2.6 KiB
C

/* $Id$ */
/* Copyright (c) 2004-2014 Pierre Pronchery <khorben@defora.org> */
/* This file is part of DeforaOS Unix utils */
/* 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, version 3 of the License.
*
* 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, see <http://www.gnu.org/licenses/>. */
#include <unistd.h>
#include <ctype.h>
#include <stdlib.h>
#include <stdio.h>
/* strings */
static int _strings_error(char const * message, int ret);
static void _strings_do(int flgn, FILE * fp);
static int _strings(int flgn, int argc, char * argv[])
{
FILE * fp;
int i;
if(argc == 0)
{
_strings_do(flgn, stdin);
return 0;
}
for(i = 0; i < argc; i++)
{
if((fp = fopen(argv[i], "r")) == NULL)
return _strings_error(argv[i], 1);
_strings_do(flgn, fp);
if(fclose(fp) != 0)
return _strings_error(argv[i], 1);
}
return 0;
}
static int _strings_error(char const * message, int ret)
{
fputs("strings: ", stderr);
perror(message);
return ret;
}
static void _strings_do(int flgn, FILE * fp)
{
int c;
char * str;
char * p;
int i = 0;
int n;
str = malloc(flgn * sizeof(char));
n = flgn;
while((c = fgetc(fp)) != EOF)
{
if(isprint(c))
{
if(i + 1 >= n)
{
if((p = realloc(str, (i + 2) * sizeof(char)))
== NULL)
{
_strings_error("malloc", 0);
return;
}
str = p;
n = i + 2;
}
str[i++] = c;
}
else if(i >= flgn && (c == '\n' || c == '\0'))
{
str[i] = '\0';
printf("%s\n", str);
i = 0;
}
else
i = 0;
}
free(str);
}
/* usage */
static int _usage(void)
{
fputs("Usage: strings [-a][-t format][-n number][file...]\n"
" -a Scan files in their entirety\n"
" -t Precede each string with its byte offset (\"d\", \"o\" or \"h\")\n"
" -n Minimum string length\n", stderr);
return 1;
}
/* main */
int main(int argc, char * argv[])
{
int o;
int flgn = 4;
char * p;
while((o = getopt(argc, argv, "at:n:")) != -1)
switch(o)
{
case 'a':
break;
case 't':
break;
case 'n':
flgn = strtol(optarg, &p, 10);
if(*(optarg) == '\0' || *p != '\0')
return _usage();
break;
default:
return _usage();
}
return _strings(flgn, argc - optind, &argv[optind]) == 0 ? 0 : 2;
}