summaryrefslogtreecommitdiffstats
path: root/src/include/assert.h
blob: 86a943e49b7fb7970da20b519971fd42e3faee22 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
/* IBM_PROLOG_BEGIN_TAG                                                   */
/* This is an automatically generated prolog.                             */
/*                                                                        */
/* $Source: src/include/assert.h $                                        */
/*                                                                        */
/* OpenPOWER HostBoot Project                                             */
/*                                                                        */
/* COPYRIGHT International Business Machines Corp. 2011,2014              */
/*                                                                        */
/* Licensed under the Apache License, Version 2.0 (the "License");        */
/* you may not use this file except in compliance with the License.       */
/* You may obtain a copy of the License at                                */
/*                                                                        */
/*     http://www.apache.org/licenses/LICENSE-2.0                         */
/*                                                                        */
/* Unless required by applicable law or agreed to in writing, software    */
/* distributed under the License is distributed on an "AS IS" BASIS,      */
/* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or        */
/* implied. See the License for the specific language governing           */
/* permissions and limitations under the License.                         */
/*                                                                        */
/* IBM_PROLOG_END_TAG                                                     */
/** @file assert.h
 *  @brief Define the interfaces for the standard 'assert' macros.
 *
 *  There are four different assert types provided now:
 *      Standard assert behavior:
 *              assert(foo)
 *
 *      Standard assert behavior with a custom trace message:
 *              assert(foo, "This is a trace %d", 1234)
 *
 *      Critical assert, which should only be used by system libraries or
 *      code paths which cannot use trace or error logging:
 *              crit_assert(foo)
 *
 *      Kernel assert:
 *              kassert(foo)
 *
 *  Most code should use the standard asserts.  Kernel code must use kassert
 *  exclusively.  Usage of the critical assert should be limited to system
 *  library code (/src/lib, /src/sys) or init service, trace and error log.
 */
#ifndef _ASSERT_H
#define _ASSERT_H

#include <builtins.h>

#ifdef __HOSTBOOT_MODULE // Only allow traced assert in module code.
#include <trace/interface.H>
namespace TRACE { extern trace_desc_t* g_assertTraceBuffer; };
#endif

#ifdef __cplusplus
extern "C"
{
#endif

/** @enum AssertBehavior
 *  @brief Types of assert behavior used by the internal __assert function.
 */
enum AssertBehavior
{
        /** Standard assert, custom trace already done. */
    ASSERT_TRACE_DONE,
        /** Standard assert, no custom trace. */
    ASSERT_TRACE_NOTDONE,
        /** Critical / System library assert. */
    ASSERT_CRITICAL,
        /** Kernel-level assert. */
    ASSERT_KERNEL,
};

/** @fn __assert
 *  @brief Internal function utilized by assert macros to commonize handling.
 *
 *  @param[in] i_assertb - Internal enumeration used by macros to communicate
 *                         desired behavior.
 *  @param[in] i_line - Line number at which the assert macro was called.
 *
 *  Current Behaviors:
 *      User-space application - A trace is created, either a custom one
 *                               provided by the caller or a common one
 *                               determined by the trace callback hook, and
 *                               the asserting task is ended.
 *
 *      Critical library - A printk is performed, similar in structure to the
 *                         traces, and the user task is ended.
 *
 *      Kernel - A printk is performed and a while(1) loop is entered to cease
 *               user-space dispatching.
 */
NO_RETURN
void __assert(AssertBehavior i_assertb, int i_line);

#ifdef __HOSTBOOT_MODULE // Only allow traced assert in module code.

// Macro tricks to determine if there is a custom string.
#define __ASSERT_HAS_TRACE_(_1, _2, ...) _2
#define __ASSERT_HAS_TRACE(...) __ASSERT_HAS_TRACE_(0, ##__VA_ARGS__, 0)

/**
 * @brief Macro to do the custom trace if one is provided.
 *
 * This results in larger code size of the caller to call the trace routines
 * but may provide additional debug information.
 *
 * The "code" here will be compiled down to nothing or a single trace call by
 * the optimizer.  Search for "Constant Folding" for compiler background.
 */
#define __ASSERT_DO_TRACE(expr, ...)  \
        { \
            if (__ASSERT_HAS_TRACE(__VA_ARGS__)) \
            { \
                TRACFCOMP(TRACE::g_assertTraceBuffer, \
                          "Assertion [ " #expr " ] failed; " __VA_ARGS__); \
            } \
        }

/**
 * @brief Standard assert macro.
 *
 * Verfies condition, calls custom trace if provided, and calls internal
 * __assert function for remainder of common assert behavior.
 */
#define assert(expr,...) \
{\
    if (unlikely(!(expr)))\
    {\
        __ASSERT_DO_TRACE(expr, __VA_ARGS__); \
        __assert((__ASSERT_HAS_TRACE(__VA_ARGS__) ? \
                 ASSERT_TRACE_DONE : ASSERT_TRACE_NOTDONE),\
                 __LINE__);\
    }\
}

#else   // Only allow kernel assert in non-module code.

/**
 * @brief Kernel assert macro.
 *
 * Verifies condition and calls __assert function for common behavior.
 */
#define kassert(expr) \
{\
    if (unlikely(!(expr)))\
    {\
        __assert(ASSERT_KERNEL, __LINE__);\
    }\
}

#endif  // ifdef __HOSTBOOT_MODULE

// Allow critical assert anywhere.
/**
 * @brief Critical assert macro.
 *
 * Verifies condition and calls __assert function for common behavior.
 */
#define crit_assert(expr) \
{\
    if (unlikely(!(expr)))\
    {\
        __assert(ASSERT_CRITICAL, __LINE__);\
    }\
}



#ifdef NDEBUG  // Empty macro definitions for when NDEBUG is defined.
#ifdef MODULE
#undef assert
#define assert(expr,...) { }
#else
#undef kassert
#define kassert(expr) { }
#endif
#undef crit_assert
#define crit_assert(expr,...) { }
#endif



/** @brief  Make an assertion at compile time. If Boolean expression exp
 *  is false, then the compile will stop with an error.  Example usage:
 *            CPPASSERT( 2 == sizeof(compId_t));
 *  which would be used in front of errl flattening code that assumes
 *  compId_t is 2 bytes in size.  Also with the use of -f short-enums
 *  compiler switch, one could assert
 *            CPPASSERT( 1 == sizeof(errlEventType_t));
 *  If the assertion fails, it will be a wakeup call that the errlEventType_t
 *  enum has grown larger than a byte in size.  The mechanism to abend the
 *  compile when the expression is false is to cause a typedef of a char array
 *  that is -1 bytes in size.
 *
 *  Similar:  #define CHECK_SIZE(DATA, EXPECTED_SIZE)\
 *       typedef char CHECKSIZEVAR[(EXPECTED_SIZE == sizeof(DATA)) -1]
 *
 */
#define CPPASSERT(exp) typedef char compile_time_assert_failed[2*((exp)?1:0)-1]


#ifdef __cplusplus
};
#endif

#endif
OpenPOWER on IntegriCloud