| // Copyright 2012 The Chromium Authors |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include"base/location.h" |
| |
| #include<string_view> |
| |
| #include"base/compiler_specific.h" |
| #include"base/strings/string_number_conversions.h" |
| #include"base/strings/stringprintf.h" |
| #include"base/trace_event/trace_event.h" |
| |
| #if defined(COMPILER_MSVC) |
| #include<intrin.h> |
| #endif |
| |
| namespace base{ |
| |
| namespace{ |
| |
| #if defined(__clang__) && defined(_MSC_VER) |
| constexpr std::string_view kThisFilePath="base\\location.cc"; |
| #else |
| constexpr std::string_view kThisFilePath="base/location.cc"; |
| #endif |
| |
| // Finds the length of the build folder prefix from the file path. |
| // TODO(ssid): Strip prefixes from stored strings in the binary. This code only |
| // skips the prefix while reading the file name strings at runtime. |
| constexprsize_tStrippedFilePathPrefixLength(){ |
| constexpr std::string_view kPath= __FILE__; |
| // Only keep the file path starting from the src directory. |
| |
| constexprsize_t kPathLen= kPath.size(); |
| constexprsize_t kStrippedLen= kThisFilePath.size(); |
| static_assert(kPathLen>= kStrippedLen, |
| "Invalid file path for base/location.cc."); |
| return kPathLen- kStrippedLen; |
| } |
| |
| constexprsize_t kStrippedPrefixLength=StrippedFilePathPrefixLength(); |
| |
| // Returns true if the |name| string has |prefix_len| characters in the prefix |
| // and the suffix matches the |expected| string. |
| // TODO(ssid): With C++20 we can make base::EndsWith() constexpr and use it |
| // instead. |
| constexprboolStrEndsWith(std::string_view name, |
| size_t prefix_len, |
| std::string_view expected){ |
| return name.substr(prefix_len)== expected; |
| } |
| |
| static_assert(StrEndsWith(__FILE__, kStrippedPrefixLength, kThisFilePath), |
| "The file name does not match the expected prefix format."); |
| |
| }// namespace |
| |
| Location::Location()=default; |
| Location::Location(constLocation& other)=default; |
| Location::Location(Location&& other) noexcept=default; |
| Location&Location::operator=(constLocation& other)=default; |
| |
| Location::Location(constchar* file_name,constvoid* program_counter) |
| : file_name_(file_name), program_counter_(program_counter){} |
| |
| Location::Location(constchar* function_name, |
| constchar* file_name, |
| int line_number, |
| constvoid* program_counter) |
| : function_name_(function_name), |
| file_name_(file_name), |
| line_number_(line_number), |
| program_counter_(program_counter){ |
| // The program counter should not be null except in a default constructed |
| // (empty) Location object. This value is used for identity, so if it doesn't |
| // uniquely identify a location, things will break. |
| DCHECK(program_counter); |
| } |
| |
| std::stringLocation::ToString()const{ |
| if(has_source_info()){ |
| return std::string(function_name_)+"@"+ file_name_+":"+ |
| NumberToString(line_number_); |
| } |
| returnStringPrintf("pc:%p", program_counter_); |
| } |
| |
| voidLocation::WriteIntoTrace(perfetto::TracedValue context)const{ |
| auto dict= std::move(context).WriteDictionary(); |
| dict.Add("function_name", function_name_); |
| dict.Add("file_name", file_name_); |
| dict.Add("line_number", line_number_); |
| } |
| |
| #if defined(COMPILER_MSVC) |
| #define RETURN_ADDRESS()_ReturnAddress() |
| #elif defined(COMPILER_GCC) |
| #define RETURN_ADDRESS() \ |
| __builtin_extract_return_addr(__builtin_return_address(0)) |
| #else |
| #define RETURN_ADDRESS()nullptr |
| #endif |
| |
| // static |
| NOINLINELocationLocation::Current(constchar* function_name, |
| constchar* file_name, |
| int line_number){ |
| returnLocation(function_name, UNSAFE_TODO(file_name+ kStrippedPrefixLength), |
| line_number, RETURN_ADDRESS()); |
| } |
| |
| // static |
| NOINLINELocationLocation::CurrentWithoutFunctionName(constchar* file_name, |
| int line_number){ |
| returnLocation(nullptr, UNSAFE_TODO(file_name+ kStrippedPrefixLength), |
| line_number, RETURN_ADDRESS()); |
| } |
| |
| //------------------------------------------------------------------------------ |
| NOINLINEconstvoid*GetProgramCounter(){ |
| return RETURN_ADDRESS(); |
| } |
| |
| }// namespace base |
