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#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <magic.h>
/* magic_ofs - check for 'file' magic at any possible offset within a file
*
* (C) 2003 by Harald Welte <laforge@gnumonks.org>
*
* This code is subject to the GNU GPL v2
*/
int main(int argc, char **argv)
{
struct stat st;
magic_t cookie;
int fd;
off_t i;
void *mem;
if (argc < 2) {
fprintf(stderr, "you have to name a file\n");
exit(2);
}
if (!strlen(argv[1])) {
fprintf(stderr, "empty argument\n");
exit(2);
}
fd = open(argv[1], 0);
if (fd < 0) {
fprintf(stderr, "unable to open file\n");
exit(1);
}
if (fstat(fd, &st)) {
fprintf(stderr, "unable to stat file\n");
exit(1);
}
mem = mmap(0, st.st_size, PROT_READ, MAP_SHARED, fd, (off_t ) 0);
if (!mem) {
fprintf(stderr, "unable to mmap file\n");
exit(1);
}
cookie = magic_open(MAGIC_CONTINUE);
if (!cookie) {
fprintf(stderr, "error opening libmagic\n");
exit(1);
}
if (magic_load(cookie, NULL)) {
fprintf(stderr, "error during magic_load\n");
magic_close(cookie);
exit(1);
}
for (i = 0; i < st.st_size; i++) {
const char *desc;
desc = magic_buffer(cookie, mem+i, st.st_size - i);
if (!desc) {
break;
}
if (!strcmp(desc, "data")) {
continue;
}
printf("%8.8u: %s\n", i, desc);
}
magic_close(cookie);
exit(0);
}
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