r4790: added type checking helper macros in talloc. These take advantage of

the type names that talloc already keeps around for pointers, and
allows the user to type check void* private pointers. It can also be
used to implement polymorphism in C, as I'm sure someone would have
pointed out to me sooner or later :-)
(This used to be commit c283e1a3efac3a92e29a35856e20eb61ef4c221e)

1 files changed, 32 insertions, 0 deletions

diff --git a/source4/lib/talloc/talloc_guide.txt b/source4/lib/talloc/talloc_guide.txt
index 30b7f64d67..927bd366fd 100644
--- a/source4/lib/talloc/talloc_guide.txt
+++ b/source4/lib/talloc/talloc_guide.txt
@@ -512,3 +512,35 @@ void *talloc_autofree_context(void);
 This is a handy utility function that returns a talloc context
 which will be automatically freed on program exit. This can be used
 to reduce the noise in memory leak reports.
+
+
+=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
+void *talloc_check_name(const void *ptr, const char *name);
+
+This function checks if a pointer has the specified name. If it does
+then the pointer is returned. It it doesn't then NULL is returned.
+
+
+=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
+(type *)talloc_get_type(const void *ptr, type);
+
+This macro allows you to do type checking on talloc pointers. It is
+particularly useful for void* private pointers. It is equivalent to
+this:
+
+   (type *)talloc_check_name(ptr, #type)
+
+
+=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
+talloc_set_type(const void *ptr, type);
+
+This macro allows you to force the name of a pointer to be a
+particular type. This can be used in conjunction with
+talloc_get_type() to do type checking on void* pointers.
+
+It is equivalent to this:
+   talloc_set_name_const(ptr, #type)
+
+
+
+