    /*
     * There are two expected ways of including this header.
     *
     * 1) The "default" case (expected from tools etc).
     *
     * Simply #include <public/errno.h>
     *
     * In this circumstance, normal header guards apply and the includer shall get
     * an enumeration in the XEN_xxx namespace, appropriate for C or assembly.
     *
     * 2) The special case where the includer provides a XEN_ERRNO() in scope.
     *
     * In this case, no inclusion guards apply and the caller is responsible for
     * their XEN_ERRNO() being appropriate in the included context.  The header
     * will unilaterally #undef XEN_ERRNO().
     */

    #ifndef XEN_ERRNO

    /*
     * Includer has not provided a custom XEN_ERRNO().  Arrange for normal header
     * guards, an automatic enum (for C code) and constants in the XEN_xxx
     * namespace.
     */
    #ifndef __XEN_PUBLIC_ERRNO_H__
    #define __XEN_PUBLIC_ERRNO_H__

    #define XEN_ERRNO_DEFAULT_INCLUDE

    #ifndef __ASSEMBLY__

    #define XEN_ERRNO(name, value) XEN_##name = value,
    enum xen_errno {

    #elif __XEN_INTERFACE_VERSION__ < 0x00040700

    #define XEN_ERRNO(name, value) .equ XEN_##name, value

    #endif /* __ASSEMBLY__ */

    #endif /* __XEN_PUBLIC_ERRNO_H__ */
    #endif /* !XEN_ERRNO */

    /* ` enum neg_errnoval {  [ -Efoo for each Efoo in the list below ]  } */
    /* ` enum errnoval { */

    #ifdef XEN_ERRNO

    /*
     * Values originating from x86 Linux. Please consider using respective
     * values when adding new definitions here.
     *
     * The set of identifiers to be added here shouldn't extend beyond what
     * POSIX mandates (see e.g.
     * http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/errno.h.html)
     * with the exception that we support some optional (XSR) values
     * specified there (but no new ones should be added).
     */

    XEN_ERRNO(EPERM,	 1)	/* Operation not permitted */
    XEN_ERRNO(ENOENT,	 2)	/* No such file or directory */
    XEN_ERRNO(ESRCH,	 3)	/* No such process */
    #ifdef __XEN__ /* Internal only, should never be exposed to the guest. */
    XEN_ERRNO(EINTR,	 4)	/* Interrupted system call */
    #endif
    XEN_ERRNO(EIO,		 5)	/* I/O error */
    XEN_ERRNO(ENXIO,	 6)	/* No such device or address */
    XEN_ERRNO(E2BIG,	 7)	/* Arg list too long */
    XEN_ERRNO(ENOEXEC,	 8)	/* Exec format error */
    XEN_ERRNO(EBADF,	 9)	/* Bad file number */
    XEN_ERRNO(ECHILD,	10)	/* No child processes */
    XEN_ERRNO(EAGAIN,	11)	/* Try again */
    XEN_ERRNO(EWOULDBLOCK,	11)	/* Operation would block.  Aliases EAGAIN */
    XEN_ERRNO(ENOMEM,	12)	/* Out of memory */
    XEN_ERRNO(EACCES,	13)	/* Permission denied */
    XEN_ERRNO(EFAULT,	14)	/* Bad address */
    XEN_ERRNO(EBUSY,	16)	/* Device or resource busy */
    XEN_ERRNO(EEXIST,	17)	/* File exists */
    XEN_ERRNO(EXDEV,	18)	/* Cross-device link */
    XEN_ERRNO(ENODEV,	19)	/* No such device */
    XEN_ERRNO(EISDIR,	21)	/* Is a directory */
    XEN_ERRNO(EINVAL,	22)	/* Invalid argument */
    XEN_ERRNO(ENFILE,	23)	/* File table overflow */
    XEN_ERRNO(EMFILE,	24)	/* Too many open files */
    XEN_ERRNO(ENOSPC,	28)	/* No space left on device */
    XEN_ERRNO(EROFS,	30)	/* Read-only file system */
    XEN_ERRNO(EMLINK,	31)	/* Too many links */
    XEN_ERRNO(EDOM,		33)	/* Math argument out of domain of func */
    XEN_ERRNO(ERANGE,	34)	/* Math result not representable */
    XEN_ERRNO(EDEADLK,	35)	/* Resource deadlock would occur */
    XEN_ERRNO(EDEADLOCK,	35)	/* Resource deadlock would occur. Aliases EDEADLK */
    XEN_ERRNO(ENAMETOOLONG,	36)	/* File name too long */
    XEN_ERRNO(ENOLCK,	37)	/* No record locks available */
    XEN_ERRNO(ENOSYS,	38)	/* Function not implemented */
    XEN_ERRNO(ENOTEMPTY,	39)	/* Directory not empty */
    XEN_ERRNO(ENODATA,	61)	/* No data available */
    XEN_ERRNO(ETIME,	62)	/* Timer expired */
    XEN_ERRNO(EBADMSG,	74)	/* Not a data message */
    XEN_ERRNO(EOVERFLOW,	75)	/* Value too large for defined data type */
    XEN_ERRNO(EILSEQ,	84)	/* Illegal byte sequence */
    #ifdef __XEN__ /* Internal only, should never be exposed to the guest. */
    XEN_ERRNO(ERESTART,	85)	/* Interrupted system call should be restarted */
    #endif
    XEN_ERRNO(ENOTSOCK,	88)	/* Socket operation on non-socket */
    XEN_ERRNO(EOPNOTSUPP,	95)	/* Operation not supported on transport endpoint */
    XEN_ERRNO(EADDRINUSE,	98)	/* Address already in use */
    XEN_ERRNO(EADDRNOTAVAIL, 99)	/* Cannot assign requested address */
    XEN_ERRNO(ENOBUFS,	105)	/* No buffer space available */
    XEN_ERRNO(EISCONN,	106)	/* Transport endpoint is already connected */
    XEN_ERRNO(ENOTCONN,	107)	/* Transport endpoint is not connected */
    XEN_ERRNO(ETIMEDOUT,	110)	/* Connection timed out */

    #undef XEN_ERRNO
    #endif /* XEN_ERRNO */
    /* ` } */

    /* Clean up from a default include.  Close the enum (for C). */
    #ifdef XEN_ERRNO_DEFAULT_INCLUDE
    #undef XEN_ERRNO_DEFAULT_INCLUDE
    #ifndef __ASSEMBLY__
    };
    #endif

    #endif /* XEN_ERRNO_DEFAULT_INCLUDE */