Use a vector with static storage for the backtrace

Avoid a dynamic memory allocation which may fail
Return-To-The-Roots · Jan 4, 2025 · a70e8d2 · a70e8d2
1 parent fd1d563
commit a70e8d2
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Showing 3 changed files with 20 additions and 18 deletions.
diff --git a/libs/s25client/s25client.cpp b/libs/s25client/s25client.cpp
@@ -1,4 +1,4 @@
-// Copyright (C) 2005 - 2021 Settlers Freaks (sf-team at siedler25.org)
+// Copyright (C) 2005 - 2025 Settlers Freaks (sf-team at siedler25.org)
 //
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -170,7 +170,7 @@ void showCrashMessage()
 
 void handleException(void* pCtx = nullptr) noexcept
 {
-    std::vector<void*> stacktrace = DebugInfo::GetStackTrace(pCtx);
+    const auto stacktrace = DebugInfo::GetStackTrace(pCtx);
     try
     {
         LogTarget target = (LOG.getFileWriter()) ? LogTarget::FileAndStderr : LogTarget::Stderr;

diff --git a/libs/s25main/Debug.cpp b/libs/s25main/Debug.cpp
@@ -11,12 +11,12 @@
 #include "backtrace_config.h"
 #include "network/GameClient.h"
 #include "s25util/Log.h"
+#include <boost/core/ignore_unused.hpp>
 #include <boost/endian/arithmetic.hpp>
 #include <boost/endian/conversion.hpp>
 #include <boost/nowide/iostream.hpp>
 #include <bzlib.h>
 #include <memory>
-#include <vector>
 
 #if RTTR_BACKTRACE_HAS_DBGHELP
 #    include <windows.h>
@@ -43,7 +43,7 @@ typedef WINBOOL(WINAPI* StackWalkType)(DWORD MachineType, HANDLE hProcess, HANDL
 namespace {
 #if RTTR_BACKTRACE_HAS_DBGHELP
 #    define RTTR_CONTEXT_PTR_TYPE LPCONTEXT
-bool captureBacktrace(std::vector<void*>& stacktrace, LPCONTEXT ctx = nullptr) noexcept
+bool captureBacktrace(DebugInfo::stacktrace_t& stacktrace, LPCONTEXT ctx) noexcept
 {
     CONTEXT context;
 #    ifndef _MSC_VER
@@ -131,17 +131,17 @@ bool captureBacktrace(std::vector<void*>& stacktrace, LPCONTEXT ctx = nullptr) n
     SymCleanup(process);
     return true;
 }
-#elif RTTR_BACKTRACE_HAS_FUNCTION
-bool captureBacktrace(std::vector<void*>& stacktrace, void* = nullptr) noexcept
+#else
+bool captureBacktrace(stacktrace_t& stacktrace, void*) noexcept
 {
-    unsigned num_frames = backtrace(&stacktrace[0], stacktrace.size());
+#    if RTTR_BACKTRACE_HAS_FUNCTION
+    const auto num_frames = backtrace(&stacktrace[0], stacktrace.size());
     stacktrace.resize(num_frames);
     return true;
-}
-#else
-bool captureBacktrace(std::vector<void*>&, void* = nullptr) noexcept
-{
+#    else
+    boost::ignore_unused(stacktrace);
     return false;
+#    endif
 }
 #endif
 } // namespace
@@ -182,12 +182,12 @@ DebugInfo::~DebugInfo()
     sock.Close();
 }
 
-std::vector<void*> DebugInfo::GetStackTrace(void* ctx) noexcept
+DebugInfo::stacktrace_t DebugInfo::GetStackTrace(void* ctx) noexcept
 {
 #ifndef RTTR_CONTEXT_PTR_TYPE
     using RTTR_CONTEXT_PTR_TYPE = void*;
 #endif
-    std::vector<void*> stacktrace(256);
+    stacktrace_t stacktrace(stacktrace_t::static_capacity);
     if(!captureBacktrace(stacktrace, static_cast<RTTR_CONTEXT_PTR_TYPE>(ctx)))
         stacktrace.clear();
     return stacktrace;
@@ -248,7 +248,7 @@ bool DebugInfo::SendString(const std::string& str)
     return SendString(str.c_str(), str.length() + 1); // +1 to include nullptr terminator
 }
 
-bool DebugInfo::SendStackTrace(const std::vector<void*>& stacktrace)
+bool DebugInfo::SendStackTrace(const stacktrace_t& stacktrace)
 {
     if(stacktrace.empty())
         return false;

diff --git a/libs/s25main/Debug.h b/libs/s25main/Debug.h
@@ -1,12 +1,12 @@
-// Copyright (C) 2005 - 2021 Settlers Freaks (sf-team at siedler25.org)
+// Copyright (C) 2005 - 2025 Settlers Freaks (sf-team at siedler25.org)
 //
 // SPDX-License-Identifier: GPL-2.0-or-later
 
 #pragma once
 
 #include "s25util/Socket.h"
+#include <boost/container/static_vector.hpp>
 #include <boost/filesystem/path.hpp>
-#include <vector>
 
 class BinaryFile;
 
@@ -16,18 +16,20 @@ class DebugInfo
     Socket sock;
 
 public:
+    using stacktrace_t = boost::container::static_vector<void*, 256>;
+
     DebugInfo();
     ~DebugInfo();
 
-    static std::vector<void*> GetStackTrace(void* ctx = nullptr) noexcept;
+    static stacktrace_t GetStackTrace(void* ctx = nullptr) noexcept;
 
     bool Send(const void* buffer, size_t length);
     bool SendSigned(int32_t i);
     bool SendUnsigned(uint32_t i);
     bool SendString(const char* str, size_t len = 0);
     bool SendString(const std::string& str);
 
-    bool SendStackTrace(const std::vector<void*>& stacktrace);
+    bool SendStackTrace(const stacktrace_t& stacktrace);
     bool SendReplay();
     bool SendAsyncLog(const boost::filesystem::path& asyncLogFilepath);
     bool SendFile(BinaryFile& file);