1  /* SPDX-License-Identifier: GPL-2.0 */
2  /*
3   * Support for Intel Camera Imaging ISP subsystem.
4   * Copyright (c) 2015, Intel Corporation.
5   *
6   * This program is free software; you can redistribute it and/or modify it
7   * under the terms and conditions of the GNU General Public License,
8   * version 2, as published by the Free Software Foundation.
9   *
10   * This program is distributed in the hope it will be useful, but WITHOUT
11   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13   * more details.
14   */
15  
16  #ifndef __ASSERT_SUPPORT_H_INCLUDED__
17  #define __ASSERT_SUPPORT_H_INCLUDED__
18  
19  /**
20   * The following macro can help to test the size of a struct at compile
21   * time rather than at run-time. It does not work for all compilers; see
22   * below.
23   *
24   * Depending on the value of 'condition', the following macro is expanded to:
25   * - condition==true:
26   *     an expression containing an array declaration with negative size,
27   *     usually resulting in a compilation error
28   * - condition==false:
29   *     (void) 1; // C statement with no effect
30   *
31   * example:
32   *  COMPILATION_ERROR_IF( sizeof(struct host_sp_queues) != SIZE_OF_HOST_SP_QUEUES_STRUCT);
33   *
34   * verify that the macro indeed triggers a compilation error with your compiler:
35   *  COMPILATION_ERROR_IF( sizeof(struct host_sp_queues) != (sizeof(struct host_sp_queues)+1) );
36   *
37   * Not all compilers will trigger an error with this macro; use a search engine to search for
38   * BUILD_BUG_ON to find other methods.
39   */
40  #define COMPILATION_ERROR_IF(condition) ((void)sizeof(char[1 - 2 * !!(condition)]))
41  
42  /* Compile time assertion */
43  #ifndef CT_ASSERT
44  #define CT_ASSERT(cnd) ((void)sizeof(char[(cnd) ? 1 :  -1]))
45  #endif /* CT_ASSERT */
46  
47  #include <linux/bug.h>
48  
49  /* TODO: it would be cleaner to use this:
50   * #define assert(cnd) BUG_ON(cnd)
51   * but that causes many compiler warnings (==errors) under Android
52   * because it seems that the BUG_ON() macro is not seen as a check by
53   * gcc like the BUG() macro is. */
54  #define assert(cnd) \
55  	do { \
56  		if (!(cnd)) \
57  			BUG(); \
58  	} while (0)
59  
60  #ifndef PIPE_GENERATION
61  /* Deprecated OP___assert, this is still used in ~1000 places
62   * in the code. This will be removed over time.
63   * The implementation for the pipe generation tool is in see support.isp.h */
64  #define OP___assert(cnd) assert(cnd)
65  
compile_time_assert(unsigned int cond)66  static inline void compile_time_assert(unsigned int cond)
67  {
68  	/* Call undefined function if cond is false */
69  	void _compile_time_assert(void);
70  	if (!cond) _compile_time_assert();
71  }
72  #endif /* PIPE_GENERATION */
73  
74  #endif /* __ASSERT_SUPPORT_H_INCLUDED__ */
75