| #include <sys/mman.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <unistd.h> |
| #include <string.h> |
| #include <limits.h> |
| #include <pthread.h> |
| |
| char *__strchrnul(const char *, int); |
| |
| char *__shm_mapname(const char *name, char *buf) |
| { |
| char *p; |
| while (*name == '/') name++; |
| if (*(p = __strchrnul(name, '/')) || p==name || |
| (p-name <= 2 && name[0]=='.' && p[-1]=='.')) { |
| errno = EINVAL; |
| return 0; |
| } |
| if (p-name > NAME_MAX) { |
| errno = ENAMETOOLONG; |
| return 0; |
| } |
| memcpy(buf, "/dev/shm/", 9); |
| memcpy(buf+9, name, p-name+1); |
| return buf; |
| } |
| |
| int shm_open(const char *name, int flag, mode_t mode) |
| { |
| int cs; |
| char buf[NAME_MAX+10]; |
| if (!(name = __shm_mapname(name, buf))) return -1; |
| pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs); |
| int fd = open(name, flag|O_NOFOLLOW|O_CLOEXEC|O_NONBLOCK, mode); |
| pthread_setcancelstate(cs, 0); |
| return fd; |
| } |
| |
| int shm_unlink(const char *name) |
| { |
| char buf[NAME_MAX+10]; |
| if (!(name = __shm_mapname(name, buf))) return -1; |
| return unlink(name); |
| } |