Back to index

glibc  2.9
Functions
xmknodat.c File Reference
#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>

Go to the source code of this file.

Functions

int __xmknodat (int vers, int fd, const char *file, mode_t mode, dev_t *dev)

Function Documentation

int __xmknodat ( int  vers,
int  fd,
const char *  file,
mode_t  mode,
dev_t dev 
)

Definition at line 37 of file xmknodat.c.

{
  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
}

Here is the call graph for this function: