xref: /freebsd/lib/libc/include/block_abi.h (revision 924226fba12cc9a228c73b956e1b7fa24c60b055)
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  * $FreeBSD$
27  */
28 
29 #ifdef __BLOCKS__
30 /**
31  * Declares a block variable.  This macro is defined in the trivial way for
32  * compilers that support blocks and exposing the ABI in the source for other
33  * compilers.
34  */
35 #define	DECLARE_BLOCK(retTy, name, argTys, ...)\
36 	retTy(^name)(argTys, ## __VA_ARGS__)
37 /**
38  * Calls a block variable.  This macro is defined in the trivial way for
39  * compilers that support blocks and exposing the ABI in the source for other
40  * compilers.
41  */
42 #define CALL_BLOCK(name, ...) name(__VA_ARGS__)
43 #else // !__BLOCKS__
44 #define	DECLARE_BLOCK(retTy, name, argTys, ...)\
45 	struct {\
46 		void *isa;\
47 		int flags;\
48 		int reserved;\
49 		retTy (*invoke)(void *, ...);\
50 	} *name
51 #define CALL_BLOCK(name, ...) (name)->invoke(name, __VA_ARGS__)
52 #endif // __BLOCKS__
53 /**
54  * Returns the pointer to the block-invoke function.  This is used for passing
55  * blocks to functions that want a function pointer and a data pointer.
56  */
57 #define GET_BLOCK_FUNCTION(x) \
58 	(((struct {\
59 		void *isa;\
60 		int flags;\
61 		int reserved;\
62 		void (*invoke)(void *, ...);\
63 	}*)(void*)x)->invoke)
64