44 lines
953 B
C
44 lines
953 B
C
#include <sys/mman.h>
|
|
#include <errno.h>
|
|
#include <fcntl.h>
|
|
#include <unistd.h>
|
|
#include <string.h>
|
|
#include <limits.h>
|
|
#include <pthread.h>
|
|
|
|
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);
|
|
}
|