/*
* Copyright (C) 2013 Red Hat, Inc.
*
* All rights reserved.
*
* Author: Jan Friesse <jfriesse@redhat.com>
*
* libqb is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 2.1 of the License, or
* (at your option) any later version.
*
* libqb 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with libqb. If not, see <http://www.gnu.org/licenses/>.
*/
#include <sys/types.h>
#include <assert.h>
#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
static void usage(void)
{
printf("Usage: [ -i input_file] [ -o output_file ] [ -n no_bytes]\n");
printf("Changes no_bytes (default 1024) in input_file (default = - = stdin) and store\n");
printf("result to output_file (default = - = stdout). It's possible to use same file\n");
printf("as both input and output\n");
exit(1);
}
static void init_rand(void) {
unsigned int init_v;
init_v = time(NULL) + getpid();
srand(init_v);
}
int main(int argc, char *argv[])
{
FILE *fi, *fo;
int i;
const char *input_file_name;
const char *output_file_name;
int no_bytes;
char *ep;
int ch;
unsigned char *data;
size_t data_size;
size_t data_pos;
size_t input_data_size;
unsigned char buf[1024];
input_file_name = "-";
output_file_name = "-";
no_bytes = 1024;
while ((ch = getopt(argc, argv, "hi:o:n:")) != -1) {
switch (ch) {
case 'i':
input_file_name = optarg;
break;
case 'n':
no_bytes = strtol(optarg, &ep, 10);
if (no_bytes < 0 || *ep != '\0') {
warnx("illegal number -- %s", argv[2]);
usage();
}
break;
case 'o':
output_file_name = optarg;
break;
case 'h':
case '?':
default:
usage();
/* NOTREACHED */
}
}
if (strcmp(input_file_name, "-") == 0) {
fi = stdin;
} else {
fi = fopen(input_file_name, "rb");
if (fi == NULL) {
err(1, "%s", input_file_name);
}
}
/*
* Open and fully read input file
*/
data = NULL;
data_size = 0;
data_pos = 0;
while ((input_data_size = fread(buf, 1, sizeof(buf), fi)) != 0) {
if (data_pos + input_data_size >= data_size) {
data_size = (data_size + input_data_size) * 2;
assert((data = realloc(data, data_size)) != NULL);
}
memcpy(data + data_pos, buf, input_data_size);
data_pos += input_data_size;
}
fclose(fi);
/*
* Change bytes
*/
init_rand();
for (i = 0; i < no_bytes; i++) {
data[rand() % data_pos] = rand();
}
/*
* Fully write ouput file
*/
if (strcmp(output_file_name, "-") == 0) {
fo = stdout;
} else {
fo = fopen(output_file_name, "wb");
if (fo == NULL) {
err(1, "%s", output_file_name);
}
}
assert(fwrite(data, 1, data_pos, fo) == data_pos);
fclose(fo);
free(data);
return (0);
}