pw_polyfill/c_test.c

// Copyright 2024 The Pigweed Authors
//
// 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
//
//     https://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.

#define ARRAY_LEN(array) (sizeof(array) / sizeof(*array))

// DOCSTAG: [static_assert-example]

#include "pw_polyfill/standard.h"
#include "pw_polyfill/static_assert.h"

extern int array[3];

static_assert(ARRAY_LEN(array) == 3, "The array must contain 3 elements");

static_assert(sizeof(array) == 3 * sizeof(int));  // The message is optional.

// DOCSTAG: [static_assert-example]

#if 0  // failing asserts

static_assert(0);  // no message
static_assert(0, "This static assert should FAIL");

#endif  // 0

// static_assert should continue to work even if <assert.h> is included, but,
// depending on the library, the <assert.h> version of static_assert may
// override pw_polyfill's, so the message argument may be required.

#include <assert.h>

static_assert(1, "This static assert should PASS");

// Tests for pw_polyfill/standard.h

// Test that the PW_C_STANDARD_IS_SUPPORTED() is true for C89 and C99 since
// support is required in Pigweed.
static_assert(PW_C_STANDARD_IS_SUPPORTED(89),
              "Macro must be true since Pigweed requires C99 or newer");
static_assert(PW_C_STANDARD_IS_SUPPORTED(99),
              "Macro must be true since Pigweed requires C99 or newer");

// Test that PW_C_STANDARD_IS_SUPPORTED() for C11, C17, and C23 is true or false
// depending on the value of __STDC_VERSION__.
static_assert(PW_C_STANDARD_IS_SUPPORTED(11) == (__STDC_VERSION__ >= 201112L),
              "Macro value should match __STDC_VERSION__");
static_assert(PW_C_STANDARD_IS_SUPPORTED(17) == (__STDC_VERSION__ >= 201710L),
              "Macro value should match __STDC_VERSION__");
static_assert(PW_C_STANDARD_IS_SUPPORTED(23) == (__STDC_VERSION__ >= 202311L),
              "Macro value should match __STDC_VERSION__");

// Test that PW_CXX_STANDARD_IS_SUPPORTED() is always false since this is a C
// file.
static_assert(!PW_CXX_STANDARD_IS_SUPPORTED(98),
              "PW_CXX_STANDARD_IS_SUPPORTED() must always be false in C");
static_assert(!PW_CXX_STANDARD_IS_SUPPORTED(11),
              "PW_CXX_STANDARD_IS_SUPPORTED() must always be false in C");
static_assert(!PW_CXX_STANDARD_IS_SUPPORTED(14),
              "PW_CXX_STANDARD_IS_SUPPORTED() must always be false in C");
static_assert(!PW_CXX_STANDARD_IS_SUPPORTED(17),
              "PW_CXX_STANDARD_IS_SUPPORTED() must always be false in C");
static_assert(!PW_CXX_STANDARD_IS_SUPPORTED(20),
              "PW_CXX_STANDARD_IS_SUPPORTED() must always be false in C");
static_assert(!PW_CXX_STANDARD_IS_SUPPORTED(23),
              "PW_CXX_STANDARD_IS_SUPPORTED() must always be false in C");