-/* Copyright (C) 2000-2021 Free Software Foundation, Inc.
+/* shm_open -- open a POSIX shared memory object. Generic POSIX file version.
+ Copyright (C) 2001-2021 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
<https://www.gnu.org/licenses/>. */
#include <errno.h>
-#include <sys/mman.h>
+#include <fcntl.h>
+#include <pthread.h>
+#include <shm-directory.h>
+#include <unistd.h>
/* Open shared memory object. */
int
shm_open (const char *name, int oflag, mode_t mode)
{
- __set_errno (ENOSYS);
- return -1;
+ struct shmdir_name dirname;
+ if (__shm_get_name (&dirname, name, false) != 0)
+ {
+ __set_errno (EINVAL);
+ return -1;
+ }
+
+ oflag |= O_NOFOLLOW | O_CLOEXEC;
+
+ /* Disable asynchronous cancellation. */
+ int state;
+ pthread_setcancelstate (PTHREAD_CANCEL_DISABLE, &state);
+
+ int fd = open (dirname.name, oflag, mode);
+ if (fd == -1 && __glibc_unlikely (errno == EISDIR))
+ /* It might be better to fold this error with EINVAL since
+ directory names are just another example for unsuitable shared
+ object names and the standard does not mention EISDIR. */
+ __set_errno (EINVAL);
+
+ pthread_setcancelstate (state, NULL);
+
+ return fd;
}
-stub_warning (shm_open)