xref: /freebsd/lib/libc/include/block_abi.h (revision b3e7694832e81d7a904a10f525f8797b753bf0d3)
1 /*-
2  * Copyright (c) 2014 David T Chisnall
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #ifdef __BLOCKS__
28 /**
29  * Declares a block variable.  This macro is defined in the trivial way for
30  * compilers that support blocks and exposing the ABI in the source for other
31  * compilers.
32  */
33 #define	DECLARE_BLOCK(retTy, name, argTys, ...)\
34 	retTy(^name)(argTys, ## __VA_ARGS__)
35 /**
36  * Calls a block variable.  This macro is defined in the trivial way for
37  * compilers that support blocks and exposing the ABI in the source for other
38  * compilers.
39  */
40 #define CALL_BLOCK(name, ...) name(__VA_ARGS__)
41 #else // !__BLOCKS__
42 #define	DECLARE_BLOCK(retTy, name, argTys, ...)\
43 	struct {\
44 		void *isa;\
45 		int flags;\
46 		int reserved;\
47 		retTy (*invoke)(void *, ...);\
48 	} *name
49 #define CALL_BLOCK(name, ...) (name)->invoke(name, __VA_ARGS__)
50 #endif // __BLOCKS__
51 /**
52  * Returns the pointer to the block-invoke function.  This is used for passing
53  * blocks to functions that want a function pointer and a data pointer.
54  */
55 #define GET_BLOCK_FUNCTION(x) \
56 	(((struct {\
57 		void *isa;\
58 		int flags;\
59 		int reserved;\
60 		void (*invoke)(void *, ...);\
61 	}*)(void*)x)->invoke)
62