1 /* 2 * Copyright (c) 2015 The Chromium OS Authors. All rights reserved. 3 * Use of this source code is governed by a BSD-style license that can be 4 * found in the LICENSE file. 5 */ 6 7 #include <fcntl.h> 8 #include <stdlib.h> 9 #include <unistd.h> 10 11 #include <sys/mman.h> 12 #include <sys/stat.h> 13 #include <sys/types.h> 14 main(void)15int main(void) 16 { 17 char *buf; 18 int fd, ret; 19 unsigned int i; 20 21 fd = open("/dev/zero", O_RDONLY); 22 if (fd < 0) 23 return 1; 24 25 buf = mmap(NULL, 4096, PROT_READ, MAP_PRIVATE, fd, 0); 26 if (buf == (char *)-1) 27 return 2; 28 29 for (i = 0; i < 4096; i++) { 30 if (buf[i] != 0) 31 return 3; 32 } 33 34 ret = munmap(buf, 4096); 35 if (ret < 0) 36 return 4; 37 38 ret = close(fd); 39 if (ret < 0) 40 return 5; 41 42 return 0; 43 } 44