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ws_assert.h
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1
10#ifndef __WS_ASSERT_H__
11#define __WS_ASSERT_H__
12
13#include <ws_symbol_export.h>
14#include <ws_attributes.h>
15#include <stdbool.h>
16#include <string.h>
17#include <wsutil/wslog.h>
18#include <wsutil/wmem/wmem.h>
19
20/*
21 * XXX - WS_ASSERT_ENABLED is tested in various if statements
22 * below, so that we don't test various assertions unless
23 * assertions are enabled. Compilers will often partially
24 * evaluate (CONSTANT && (expression)) at compile time, so
25 * that if CONSTANT is 0 the rest of the test isn't evaluated
26 * and assumed to result in a false result, with the code in
27 * the if branch being removed, and if CONSTANT is 1, the
28 * code is treated as an if that tests the expression.
29 *
30 * This could mean that, if "defined but not used" tests are
31 * being done, any variable tested in the expression may be warned
32 * as "defined but not used" if WS_ASSERT_ENABLED is 0, causing
33 * a pile of warnings if the variable isn't marked as unused
34 * (especially true of parametre variables).
35 *
36 * However, some compilers - Clang, in my tests, and probably GCC,
37 * due to tests in builds not failing - treat "if (0 && (expression))"
38 * specially, pretending hat all variables in the expression are used,
39 * even if they aren't used in the generated code. (At least in
40 * Apple clang version 15.0.0 (clang-1500.1.0.2.5), it must be
41 * exactly 0 - (0) doesn't have the same effect.)
42 *
43 * That's all very well, but, unfortunately Microsoft Visual Studio's
44 * C compiler doesn't do that, so the variables have to be marked as
45 * unused, which may cause warnings "used, but marked as unused"
46 * warnings if the code is compiled with assertions enabled.
47 */
48#if defined(ENABLE_ASSERT)
49#define WS_ASSERT_ENABLED 1
50#elif defined(NDEBUG)
51#define WS_ASSERT_ENABLED 0
52#else
53#define WS_ASSERT_ENABLED 1
54#endif
55
56#ifdef __cplusplus
57extern "C" {
58#endif /* __cplusplus */
59
73#define ws_assert_if_active(active, expr) \
74 do { \
75 if ((active) && !(expr)) \
76 ws_error("assertion failed: %s", #expr); \
77 } while (0)
78
89#define ws_abort_if_fail(expr) \
90 ws_assert_if_active(true, expr)
91
102#define ws_assert(expr) \
103 ws_assert_if_active(WS_ASSERT_ENABLED, expr)
104
105
116#define ws_assert_streq(s1, s2) \
117 ws_assert((s1) && (s2) && strcmp((s1), (s2)) == 0)
118
130#define ws_assert_utf8(str, len) \
131 do { \
132 const char *__assert_endptr; \
133 if (WS_ASSERT_ENABLED && \
134 !g_utf8_validate(str, len, &__assert_endptr)) { \
135 ws_log_utf8_full(LOG_DOMAIN_UTF_8, LOG_LEVEL_ERROR, \
136 __FILE__, __LINE__, __func__, \
137 str, len, __assert_endptr); \
138 } \
139 } while (0)
140
141/*
142 * We don't want to disable ws_assert_not_reached() with (optional) assertions
143 * disabled.
144 * That would blast compiler warnings everywhere for no benefit, not
145 * even a miniscule performance gain. Reaching this function is always
146 * a programming error and will unconditionally abort execution.
147 *
148 * Note: With g_assert_not_reached() if the compiler supports unreachable
149 * built-ins (which recent versions of GCC and MSVC do) there is no warning
150 * blast with g_assert_not_reached() and G_DISABLE_ASSERT. However if that
151 * is not the case then g_assert_not_reached() is simply (void)0 and that
152 * causes the spurious warnings, because the compiler can't tell anymore
153 * that a certain code path is not used. We avoid that with
154 * ws_assert_not_reached(). There is no reason to ever use a no-op here.
155 */
156
166#define ws_assert_not_reached() \
167 ws_error("assertion \"not reached\" failed")
168
169/*
170 * These macros can be used as an alternative to ws_assert() to
171 * assert some condition on function arguments. This must only be used
172 * to catch programming errors, in situations where an assertion is
173 * appropriate. And it should only be used if failing the condition
174 * doesn't necessarily lead to an inconsistent state for the program.
175 *
176 * It is possible to set the fatal log domain to "InvalidArg" to abort
177 * execution for debugging purposes, if one of these checks fail.
178 */
179
191#define ws_warn_badarg(str) \
192 ws_log_full(LOG_DOMAIN_EINVAL, LOG_LEVEL_WARNING, \
193 __FILE__, __LINE__, __func__, \
194 "invalid argument: %s", str)
195
207#define ws_return_str_if(expr, scope) \
208 do { \
209 if (WS_ASSERT_ENABLED && (expr)) { \
210 ws_warn_badarg(#expr); \
211 return wmem_strdup_printf(scope, "(invalid argument: %s)", #expr); \
212 } \
213 } while (0)
214
225#define ws_return_val_if(expr, val) \
226 do { \
227 if (WS_ASSERT_ENABLED && (expr)) { \
228 ws_warn_badarg(#expr); \
229 return (val); \
230 } \
231 } while (0)
232
233#ifdef __cplusplus
234}
235#endif /* __cplusplus */
236
237#endif /* __WS_ASSERT_H__ */
wmem.h
wslog.h