From 8a6d48c0542876eb3acfc0970c0ab7872db08d5f Mon Sep 17 00:00:00 2001 From: Zheng Da Date: Sun, 6 Dec 2009 05:26:23 +0100 Subject: check in the original version of dde linux26. --- libdde_linux26/contrib/include/linux/err.h | 52 ++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) create mode 100644 libdde_linux26/contrib/include/linux/err.h (limited to 'libdde_linux26/contrib/include/linux/err.h') diff --git a/libdde_linux26/contrib/include/linux/err.h b/libdde_linux26/contrib/include/linux/err.h new file mode 100644 index 00000000..ec87f314 --- /dev/null +++ b/libdde_linux26/contrib/include/linux/err.h @@ -0,0 +1,52 @@ +#ifndef _LINUX_ERR_H +#define _LINUX_ERR_H + +#include + +#include + +/* + * Kernel pointers have redundant information, so we can use a + * scheme where we can return either an error code or a dentry + * pointer with the same return value. + * + * This should be a per-architecture thing, to allow different + * error and pointer decisions. + */ +#define MAX_ERRNO 4095 + +#ifndef __ASSEMBLY__ + +#define IS_ERR_VALUE(x) unlikely((x) >= (unsigned long)-MAX_ERRNO) + +static inline void *ERR_PTR(long error) +{ + return (void *) error; +} + +static inline long PTR_ERR(const void *ptr) +{ + return (long) ptr; +} + +static inline long IS_ERR(const void *ptr) +{ + return IS_ERR_VALUE((unsigned long)ptr); +} + +/** + * ERR_CAST - Explicitly cast an error-valued pointer to another pointer type + * @ptr: The pointer to cast. + * + * Explicitly cast an error-valued pointer to another pointer type in such a + * way as to make it clear that's what's going on. + */ +static inline void *ERR_CAST(const void *ptr) +{ + /* cast away the const */ + return (void *) ptr; +} + +#endif + +#endif /* _LINUX_ERR_H */ -- cgit v1.2.3