AK: Add SourceLocation support

C++20 added std::source_location, which lets you capture the
callers __FILE__ / __LINE__ / __FUNCTION__ etc as a default
argument to functions.
See: https://en.cppreference.com/w/cpp/utility/source_location

During a bug investigation @ADKaster suggested we could use this
to make the LOCK_DEBUG feature of the kernel more user friendly
and allow it to automatically instrument all call sites.

We then implemented / tested it over discord. :^)

Co-Authored-by: Andrew Kaster <andrewdkaster@gmail.com>
This commit is contained in:
Brian Gianforcaro 2021-04-23 22:26:53 -07:00 committed by Linus Groh
parent b0faf2287a
commit 0ad29bc3c9
Notes: sideshowbarker 2024-07-18 19:09:06 +09:00
3 changed files with 75 additions and 0 deletions

41
AK/SourceLocation.h Normal file
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@ -0,0 +1,41 @@
/*
* Copyright (c) 2021, Andrew Kaster <andrewdkaster@gmail.com>
* Copyright (c) 2021, Brian Gianforcaro <bgianf@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/StringView.h>
#include <AK/Types.h>
namespace AK {
class SourceLocation {
public:
[[nodiscard]] constexpr StringView function_name() const { return StringView(m_function); }
[[nodiscard]] constexpr StringView file_name() const { return StringView(m_file); }
[[nodiscard]] constexpr u32 line_number() const { return m_line; }
[[nodiscard]] static constexpr SourceLocation current(const char* const file = __builtin_FILE(), u32 line = __builtin_LINE(), const char* const function = __builtin_FUNCTION())
{
return SourceLocation(file, line, function);
}
private:
constexpr SourceLocation(const char* const file, u32 line, const char* const function)
: m_function(function)
, m_file(file)
, m_line(line)
{
}
const char* const m_function { nullptr };
const char* const m_file { nullptr };
const u32 m_line { 0 };
};
}
using AK::SourceLocation;

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@ -45,6 +45,7 @@ set(AK_TEST_SOURCES
TestRefPtr.cpp TestRefPtr.cpp
TestSinglyLinkedList.cpp TestSinglyLinkedList.cpp
TestSourceGenerator.cpp TestSourceGenerator.cpp
TestSourceLocation.cpp
TestSpan.cpp TestSpan.cpp
TestString.cpp TestString.cpp
TestStringUtils.cpp TestStringUtils.cpp

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@ -0,0 +1,33 @@
/*
* Copyright (c) 2021, Andrew Kaster <andrewdkaster@gmail.com>
* Copyright (c) 2021, Brian Gianforcaro <bgianf@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/SourceLocation.h>
#include <AK/StringView.h>
#include <AK/TestSuite.h>
TEST_CASE(basic_scenario)
{
auto location = SourceLocation::current();
EXPECT_EQ(StringView(__FILE__), location.file_name());
EXPECT_EQ(StringView(__FUNCTION__), location.function_name());
EXPECT_EQ(__LINE__ - 3u, location.line_number());
}
static StringView test_default_arg(const SourceLocation& loc = SourceLocation::current())
{
return loc.function_name();
}
TEST_CASE(default_arg_scenario)
{
auto actual_calling_function = test_default_arg();
auto expected_calling_function = StringView(__FUNCTION__);
EXPECT_EQ(expected_calling_function, actual_calling_function);
}
TEST_MAIN(SourceLocation)