1 /* 2 * This program is free software; you can redistribute it and/or modify 3 * it under the terms of the GNU General Public License version 2. 4 * 5 * This program is distributed in the hope that it will be useful, 6 * but WITHOUT ANY WARRANTY; without even the implied warranty of 7 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 8 * GNU General Public License for more details. 9 * 10 * Test that shm_open open the shared memory object for writing when calling 11 * shm_open with O_RDWR even if the mode don't set write permission. 12 * 13 * The test use ftruncate to check the object is open for writing. 14 */ 15 16 /* ftruncate was formerly an XOPEN extension. We define _XOPEN_SOURCE here to 17 avoid warning if the implementation does not program ftruncate as a base 18 interface */ 19 #define _XOPEN_SOURCE 600 20 21 #include <stdio.h> 22 #include <sys/mman.h> 23 #include <sys/stat.h> 24 #include <unistd.h> 25 #include <fcntl.h> 26 #include <errno.h> 27 #include "posixtest.h" 28 29 #define BUF_SIZE 8 30 #define SHM_NAME "posixtest_20-2" 31 main()32int main() { 33 int fd, result; 34 35 result = shm_unlink(SHM_NAME); 36 if(result != 0 && errno != ENOENT) { 37 /* The shared memory object exist and shm_unlink can not 38 remove it. */ 39 perror("An error occurs when calling shm_unlink()"); 40 return PTS_UNRESOLVED; 41 } 42 43 fd = shm_open(SHM_NAME, O_RDWR|O_CREAT, 0); 44 if(fd == -1) { 45 perror("An error occurs when calling shm_open()"); 46 return PTS_UNRESOLVED; 47 } 48 49 result = ftruncate(fd, BUF_SIZE); 50 if(result == 0){ 51 printf("Test PASSED\n"); 52 shm_unlink(SHM_NAME); 53 return PTS_PASS; 54 } else if(result == -1 && errno == EINVAL) { 55 printf("The shared memory object is not opened for writing.\n"); 56 shm_unlink(SHM_NAME); 57 return PTS_FAIL; 58 } 59 60 perror("ftruncate"); 61 shm_unlink(SHM_NAME); 62 return PTS_FAIL; 63 } 64