source: asp3_tinet_ecnl_rx/trunk/musl-1.1.18/src/mman/shm_open.c@ 337

#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);
}