C++怎么实现一个简单的内存泄漏检测工具_C++重载new和delete操作符

#include <iostream>
#include <map>
#include <string>
<p>struct AllocInfo {
size_t size;
const char* file;
int line;
};</p><p>// 全局映射表，记录当前未释放的内存
extern std::map<void*, AllocInfo> g_allocations;</p><p>// 重载 new 操作符
void<em> operator new(size_t size, const char</em> file, int line);
void<em> operator new[](size_t size, const char</em> file, int line);</p><p>// 普通 new 的重载（无文件行号）
void<em> operator new(size_t size);
void</em> operator new[](size_t size);</p><p>// 重载 delete 操作符
void operator delete(void<em> ptr) noexcept;
void operator delete[](void</em> ptr) noexcept;</p><p>// 打印内存泄漏报告
void printMemoryLeaks();</p>

#include "MemoryTracker.h"
#include <iostream>
<p>std::map<void*, AllocInfo> g_allocations;</p><p>void<em> operator new(size_t size, const char</em> file, int line) {
void* ptr = malloc(size ? size : 1); // 防止 new(0)
if (ptr) {
g_allocations[ptr] = {size, file, line};
}
return ptr;
}</p><p>void<em> operator new[](size_t size, const char</em> file, int line) {
return operator new(size, file, line);
}</p><p>void* operator new(size_t size) {
return operator new(size, "unknown", 0);
}</p><p>void* operator new[](size_t size) {
return operator new[](size, "unknown", 0);
}</p><p>void operator delete(void* ptr) noexcept {
if (ptr == nullptr) return;
auto it = g_allocations.find(ptr);
if (it != g_allocations.end()) {
g_allocations.erase(it);
}
free(ptr);
}</p><p>void operator delete[](void* ptr) noexcept {
operator delete(ptr);
}</p><p>void printMemoryLeaks() {
if (g_allocations.empty()) {
std::cout << "No memory leaks detected.\n";
} else {
std::cout << "Memory leaks detected:\n";
for (const auto& pair : g_allocations) {
std::cout << "Address: " << pair.first
<< " Size: " << pair.second.size
<< " File: " << pair.second.file
<< " Line: " << pair.second.line << "\n";
}
}
}</p>

#define new new(__FILE__, __LINE__)

#include "MemoryTracker.h"
<p>// 启用带位置信息的 new</p><h1>define new new(<strong>FILE</strong>, <strong>LINE</strong>)</h1><p>int main() {
int<em> p1 = new int(42);
int</em> p2 = new int[10];</p><pre class='brush:php;toolbar:false;'>delete[] p2; // 正确释放
// delete p1; // 故意遗漏，制造泄漏

printMemoryLeaks(); // 程序退出前调用
return 0;

Memory leaks detected:
Address: 0x7fb1c8c00000 Size: 4 File: main.cpp Line: 7