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Diffstat (limited to 'sysdeps/unix/sysv/linux/xmknodat.c')
-rw-r--r--sysdeps/unix/sysv/linux/xmknodat.c95
1 files changed, 95 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/xmknodat.c b/sysdeps/unix/sysv/linux/xmknodat.c
new file mode 100644
index 0000000000..ef27b686cc
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/xmknodat.c
@@ -0,0 +1,95 @@
+/* Copyright (C) 2005, 2006 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
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/sysmacros.h>
+
+#include <sysdep.h>
+#include <kernel-features.h>
+#include <sys/syscall.h>
+#include <bp-checks.h>
+
+
+/* Create a device file named PATH relative to FD, with permission and
+   special bits MODE and device number DEV (which can be constructed
+   from major and minor device numbers with the `makedev' macro above).  */
+int
+__xmknodat (int vers, int fd, const char *file, mode_t mode, dev_t *dev)
+{
+  if (vers != _MKNOD_VER)
+    {
+      __set_errno (EINVAL);
+      return -1;
+    }
+
+  /* We must convert the value to dev_t type used by the kernel.  */
+  unsigned long long int k_dev =  (*dev) & ((1ULL << 32) - 1);
+  if (k_dev != *dev)
+    {
+      __set_errno (EINVAL);
+      return -1;
+    }
+
+#ifdef __NR_mknodat
+# ifndef __ASSUME_ATFCTS
+  if (__have_atfcts >= 0)
+# endif
+    {
+      int res = INLINE_SYSCALL (mknodat, 4, fd, file, mode,
+				(unsigned int) k_dev);
+# ifndef __ASSUME_ATFCTS
+      if (res == -1 && errno == ENOSYS)
+	__have_atfcts = -1;
+      else
+# endif
+	return res;
+    }
+#endif
+
+#ifndef __ASSUME_ATFCTS
+  char *buf = NULL;
+
+  if (fd != AT_FDCWD && file[0] != '/')
+    {
+      size_t filelen = strlen (file);
+      static const char procfd[] = "/proc/self/fd/%d/%s";
+      /* Buffer for the path name we are going to use.  It consists of
+	 - the string /proc/self/fd/
+	 - the file descriptor number
+	 - the file name provided.
+	 The final NUL is included in the sizeof.   A bit of overhead
+	 due to the format elements compensates for possible negative
+	 numbers.  */
+      size_t buflen = sizeof (procfd) + sizeof (int) * 3 + filelen;
+      buf = alloca (buflen);
+
+      __snprintf (buf, buflen, procfd, fd, file);
+      file = buf;
+    }
+
+  return INLINE_SYSCALL (mknod, 3, CHECK_STRING (file), mode,
+			 (unsigned int) k_dev);
+#endif
+}
+
+libc_hidden_def (__xmknodat)