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 does not open the shared memory object for writing when 11 * calling shm_open with O_RDONLY even if the mode set write permission. 12 * 13 * The test use ftruncate to check the object is not 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_20-1" 31 32 int main(void) 33 { 34 int fd, result; 35 36 result = shm_unlink(SHM_NAME); 37 if (result != 0 && errno != ENOENT) { 38 /* The shared memory object exist and shm_unlink can not 39 remove it. */ 40 perror("An error occurs when calling shm_unlink()"); 41 return PTS_UNRESOLVED; 42 } 43 44 fd = shm_open(SHM_NAME, O_RDONLY | O_CREAT, S_IRUSR); 45 if (fd == -1) { 46 perror("An error occurs when calling shm_open()"); 47 return PTS_UNRESOLVED; 48 } 49 50 result = ftruncate(fd, BUF_SIZE); 51 52 if (result == -1 && errno == EINVAL) { 53 printf("Test PASSED\n"); 54 shm_unlink(SHM_NAME); 55 return PTS_PASS; 56 } else if (result == 0) { 57 printf("The shared memory object is opened for writing.\n"); 58 shm_unlink(SHM_NAME); 59 return PTS_FAIL; 60 } 61 62 perror("ftruncate"); 63 shm_unlink(SHM_NAME); 64 return PTS_FAIL; 65 } 66
