[PATCH 01/32] Add an ERR_CAST() macro to complement ERR_PTR and co. [try #2]

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From: David Howells
Date: Thursday, October 4, 2007 - 8:56 am

Add an ERR_CAST() macro to complement ERR_PTR and co. for the purposes of
casting an error entyped as one pointer type to an error of another pointer
type whilst making it explicit as to what is going on.

This provides a replacement for the ERR_PTR(PTR_ERR(p)) construct.

Signed-off-by: David Howells <dhowells@redhat.com>
---

 include/linux/err.h |   12 ++++++++++++
 1 files changed, 12 insertions(+), 0 deletions(-)

diff --git a/include/linux/err.h b/include/linux/err.h
index 1ab1d44..e810ca4 100644
--- a/include/linux/err.h
+++ b/include/linux/err.h
@@ -34,6 +34,18 @@ 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)
+{
+	return (void *) ptr;
+}
+
 #endif
 
 #endif /* _LINUX_ERR_H */

-
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Messages in current thread:
[PATCH 00/32] Remove iget() and read_inode() [try #2], David Howells, (Thu Oct 4, 8:56 am)
[PATCH 01/32] Add an ERR_CAST() macro to complement ERR_PT ..., David Howells, (Thu Oct 4, 8:56 am)
[PATCH 04/32] IGET: Use iget_failed() in AFS [try #2], David Howells, (Thu Oct 4, 8:56 am)
[PATCH 05/32] IGET: Use iget_failed() in GFS2 [try #2], David Howells, (Thu Oct 4, 8:56 am)