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 the state of the shared memory object, including all data 11 * associated with the shared memory object, persists until the shared memory 12 * object is unlinked even if all other references are gone. 13 * 14 * Steps: 15 * 1. Create a shared memory object, map it and write a string in it. 16 * 2. Unmap the memory and close the file descriptor. 17 * 3. Reopen the shared memory object and remap it. 18 * 4. Check that the previously written string is always in the memory. 19 */ 20 21 /* ftruncate was formerly an XOPEN extension. We define _XOPEN_SOURCE here to 22 avoid warning if the implementation does not program ftruncate as a base 23 interface */ 24 #define _XOPEN_SOURCE 600 25 26 #include <stdio.h> 27 #include <sys/mman.h> 28 #include <sys/stat.h> 29 #include <unistd.h> 30 #include <string.h> 31 #include <fcntl.h> 32 #include <errno.h> 33 #include "posixtest.h" 34 35 #define BUF_SIZE 8 36 #define SHM_NAME "posixtest_28-1" 37 38 int main(void) 39 { 40 int fd; 41 char str[BUF_SIZE] = "qwerty"; 42 char *buf; 43 44 fd = shm_open(SHM_NAME, O_RDWR | O_CREAT, S_IRUSR | S_IWUSR); 45 if (fd == -1) { 46 perror("An error occurs when calling shm_open()"); 47 return PTS_UNRESOLVED; 48 } 49 50 if (ftruncate(fd, BUF_SIZE) != 0) { 51 perror("An error occurs when calling ftruncate()"); 52 shm_unlink(SHM_NAME); 53 return PTS_UNRESOLVED; 54 } 55 56 buf = mmap(NULL, BUF_SIZE, PROT_WRITE, MAP_SHARED, fd, 0); 57 if (buf == MAP_FAILED) { 58 perror("An error occurs when calling mmap()"); 59 shm_unlink(SHM_NAME); 60 return PTS_UNRESOLVED; 61 } 62 63 strcpy(buf, str); 64 65 if (munmap(buf, BUF_SIZE) != 0) { 66 perror("An error occurs when calling munmap()"); 67 shm_unlink(SHM_NAME); 68 return PTS_UNRESOLVED; 69 } 70 71 if (close(fd) != 0) { 72 perror("An error occurs when calling close()"); 73 shm_unlink(SHM_NAME); 74 return PTS_UNRESOLVED; 75 } 76 77 /* Now, there are no more reference on SHM_NAME but it is not unlink */ 78 79 fd = shm_open(SHM_NAME, O_RDONLY, S_IRUSR | S_IWUSR); 80 if (fd == -1 && errno == ENOENT) { 81 printf("The name of the shared memory object was removed.\n"); 82 return PTS_FAIL; 83 } else if (fd == -1) { 84 perror("An error occurs when calling shm_open()"); 85 shm_unlink(SHM_NAME); 86 return PTS_UNRESOLVED; 87 } 88 89 buf = mmap(NULL, BUF_SIZE, PROT_READ, MAP_SHARED, fd, 0); 90 if (buf == MAP_FAILED) { 91 perror("An error occurs when calling mmap()"); 92 shm_unlink(SHM_NAME); 93 return PTS_UNRESOLVED; 94 } 95 96 if (strcmp(buf, str) == 0) { 97 printf("Test PASSED\n"); 98 shm_unlink(SHM_NAME); 99 return PTS_PASS; 100 } 101 printf("The content of the shared memory object was removed.\n"); 102 shm_unlink(SHM_NAME); 103 return PTS_FAIL; 104 } 105
