Move modules to ccan/ tools to tools/

[ccan] / typesafe_cb / _info.c

diff --git a/typesafe_cb/_info.c b/typesafe_cb/_info.c
deleted file mode 100644 (file)
index 725b266..0000000
--- a/typesafe_cb/_info.c
+++ /dev/null
@@ -1,59 +0,0 @@
-#include <stdio.h>
-#include <string.h>
-#include "config.h"
-
-/**
- * typesafe_cb - macros for safe callbacks.
- *
- * The basis of the typesafe_cb header is cast_if_type(): a
- * conditional cast macro.   If an expression exactly matches a given
- * type, it is cast to the target type, otherwise it is left alone.
- *
- * This allows us to create functions which take a small number of
- * specific types, rather than being forced to use a void *.  In
- * particular, it is useful for creating typesafe callbacks as the
- * helpers typesafe_cb(), typesafe_cb_preargs() and
- * typesafe_cb_postargs() demonstrate.
- * 
- * The standard way of passing arguments to callback functions in C is
- * to use a void pointer, which the callback then casts back to the
- * expected type.  This unfortunately subverts the type checking the
- * compiler would perform if it were a direct call.  Here's an example:
- *
- *     static void my_callback(void *_obj)
- *     {
- *             struct obj *obj = _obj;
- *             ...
- *     }
- *     ...
- *             register_callback(my_callback, &my_obj);
- *
- * If we wanted to use the natural type for my_callback (ie. "void
- * my_callback(struct obj *obj)"), we could make register_callback()
- * take a void * as its first argument, but this would subvert all
- * type checking.  We really want register_callback() to accept only
- * the exactly correct function type to match the argument, or a
- * function which takes a void *.
- *
- * This is where typesafe_cb() comes in: it uses cast_if_type() to
- * cast the callback function if it matches the argument type:
- *
- *     void _register_callback(void (*cb)(void *arg), void *arg);
- *     #define register_callback(cb, arg)                              \
- *             _register_callback(typesafe_cb(void, (cb), (arg)), (arg))
- *
- * On compilers which don't support the extensions required
- * cast_if_type() and friend become an unconditional cast, so your
- * code will compile but you won't get type checking.
- */
-int main(int argc, char *argv[])
-{
-       if (argc != 2)
-               return 1;
-
-       if (strcmp(argv[1], "depends") == 0) {
-               return 0;
-       }
-
-       return 1;
-}