// -*- Mode: C++; tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*-
// vim:tabstop=4:shiftwidth=4:expandtab:
/*
* Copyright (C) 2004-2008 Wu Yongwei <adah at users dot sourceforge dot net>
*
* This software is provided 'as-is', without any express or implied
* warranty. In no event will the authors be held liable for any
* damages arising from the use of this software.
*
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute
* it freely, subject to the following restrictions:
*
* 1. The origin of this software must not be misrepresented; you must
* not claim that you wrote the original software. If you use this
* software in a product, an acknowledgement in the product
* documentation would be appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must
* not be misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source
* distribution.
*
* This file is part of Stones of Nvwa:
* http://sourceforge.net/projects/nvwa
*
*/
/**
* @file debug_new.cpp
*
* Implementation of debug versions of new and delete to check leakage.
*
* @version 4.14, 2008/10/20
* @author Wu Yongwei
*
*/
#include <QxCommon/QxConfig.h>
#include <QxCommon/QxMacro.h>
#ifndef NDEBUG
#ifndef QT_NO_DEBUG
#if _QX_USE_MEM_LEAK_DETECTION
#include <new>
#include <assert.h>
#include <limits.h>
#include <stdio.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#ifdef __unix__
#include <alloca.h>
#endif
#ifdef _WIN32
#include <windows.h>
#include <malloc.h>
#endif
#include <QtCore/qglobal.h>
#include <QxMemLeak/fast_mutex.h>
#include <QxMemLeak/static_assert.h>
#ifndef _QX_MEM_LEAK_ONLY_KNOWN_SRC_FILE
#define _QX_MEM_LEAK_ONLY_KNOWN_SRC_FILE 0
#endif // _QX_MEM_LEAK_ONLY_KNOWN_SRC_FILE
#if !_FAST_MUTEX_CHECK_INITIALIZATION && !defined(_NOTHREADS)
#error "_FAST_MUTEX_CHECK_INITIALIZATION not set: check_leaks may not work"
#endif
/**
* @def _DEBUG_NEW_ALIGNMENT
*
* The alignment requirement of allocated memory blocks. It must be a
* power of two.
*/
#ifndef _DEBUG_NEW_ALIGNMENT
#define _DEBUG_NEW_ALIGNMENT 16
#endif
/**
* @def _DEBUG_NEW_ERROR_ACTION
*
* The action to take when an error occurs. The default behaviour is to
* call \e abort, unless \c _DEBUG_NEW_ERROR_CRASH is defined, in which
* case a segmentation fault will be triggered instead (which can be
* useful on platforms like Windows that do not generate a core dump
* when \e abort is called).
*/
#ifndef _DEBUG_NEW_ERROR_ACTION
#ifndef _DEBUG_NEW_ERROR_CRASH
#define _DEBUG_NEW_ERROR_ACTION abort()
#else
#define _DEBUG_NEW_ERROR_ACTION do { *((char*)0) = 0; abort(); } while (0)
#endif
#endif
/**
* @def _DEBUG_NEW_FILENAME_LEN
*
* The length of file name stored if greater than zero. If it is zero,
* only a const char pointer will be stored. Currently the default
* behaviour is to copy the file name, because I found that the exit
* leakage check cannot access the address of the file name sometimes
* (in my case, a core dump will occur when trying to access the file
* name in a shared library after a \c SIGINT). The current default
* value makes the size of new_ptr_list_t 64 on 32-bit platforms.
*/
#ifndef _DEBUG_NEW_FILENAME_LEN
#define _DEBUG_NEW_FILENAME_LEN 44
#endif
/**
* @def _DEBUG_NEW_PROGNAME
*
* The program (executable) name to be set at compile time. It is
* better to assign the full program path to #new_progname in \e main
* (at run time) than to use this (compile-time) macro, but this macro
* serves well as a quick hack. Note also that double quotation marks
* need to be used around the program name, i.e., one should specify a
* command-line option like <code>-D_DEBUG_NEW_PROGNAME=\"a.out\"</code>
* in \e bash, or <code>-D_DEBUG_NEW_PROGNAME=\"a.exe\"</code> in the
* Windows command prompt.
*/
#ifndef _DEBUG_NEW_PROGNAME
#define _DEBUG_NEW_PROGNAME NULL
#endif
/**
* @def _DEBUG_NEW_STD_OPER_NEW
*
* Macro to indicate whether the standard-conformant behaviour of
* <code>operator new</code> is wanted. It is on by default now, but
* the user may set it to \c 0 to revert to the old behaviour.
*/
#ifndef _DEBUG_NEW_STD_OPER_NEW
#define _DEBUG_NEW_STD_OPER_NEW 1
#endif
/**
* @def _DEBUG_NEW_TAILCHECK
*
* Macro to indicate whether a writing-past-end check will be performed.
* Define it to a positive integer as the number of padding bytes at the
* end of a memory block for checking.
*/
#ifndef _DEBUG_NEW_TAILCHECK
#define _DEBUG_NEW_TAILCHECK 0
#endif
/**
* @def _DEBUG_NEW_TAILCHECK_CHAR
*
* Value of the padding bytes at the end of a memory block.
*/
#ifndef _DEBUG_NEW_TAILCHECK_CHAR
#define _DEBUG_NEW_TAILCHECK_CHAR 0xCC
#endif
/**
* @def _DEBUG_NEW_USE_ADDR2LINE
*
* Whether to use \e addr2line to convert a caller address to file/line
* information. Defining it to a non-zero value will enable the
* conversion (automatically done if GCC is detected). Defining it to
* zero will disable the conversion.
*/
#ifndef _DEBUG_NEW_USE_ADDR2LINE
#ifdef __GNUC__
#define _DEBUG_NEW_USE_ADDR2LINE 1
#else
#define _DEBUG_NEW_USE_ADDR2LINE 0
#endif
#endif
#ifdef _MSC_VER
#pragma warning(disable: 4073) // #pragma init_seg(lib) used
#pragma warning(disable: 4290) // C++ exception specification ignored
#pragma init_seg(lib)
#endif
#undef _DEBUG_NEW_EMULATE_MALLOC
#undef _DEBUG_NEW_REDEFINE_NEW
/**
* Macro to indicate whether redefinition of \c new is wanted. Here it
* is defined to \c 0 to disable the redefinition of \c new.
*/
#define _DEBUG_NEW_REDEFINE_NEW 0
#include <QxMemLeak/debug_new.h>
/**
* Gets the aligned value of memory block size.
*/
#define align(s) \
(((s) + _DEBUG_NEW_ALIGNMENT - 1) & ~(_DEBUG_NEW_ALIGNMENT - 1))
namespace qx {
namespace memory {
/**
* Structure to store the position information where \c new occurs.
*/
struct new_ptr_list_t
{
new_ptr_list_t* next;
new_ptr_list_t* prev;
size_t size;
union
{
#if _DEBUG_NEW_FILENAME_LEN == 0
const char* file;
#else
char file[_DEBUG_NEW_FILENAME_LEN];
#endif
void* addr;
};
unsigned line :31;
unsigned is_array :1;
unsigned magic;
};
/**
* Magic number for error detection.
*/
const unsigned MAGIC = 0x4442474E;
/**
* The extra memory allocated by <code>operator new</code>.
*/
const int ALIGNED_LIST_ITEM_SIZE = align(sizeof(new_ptr_list_t));
/**
* List of all new'd pointers.
*/
static new_ptr_list_t new_ptr_list = {
&new_ptr_list,
&new_ptr_list,
0,
{
#if _DEBUG_NEW_FILENAME_LEN == 0
NULL
#else
""
#endif
},
0,
0,
MAGIC
};
/**
* The mutex guard to protect simultaneous access to the pointer list.
*/
static fast_mutex new_ptr_lock;
/**
* The mutex guard to protect simultaneous output to #new_output_fp.
*/
static fast_mutex new_output_lock;
/**
* Total memory allocated in bytes.
*/
static size_t total_mem_alloc = 0;
/**
* Flag to control whether #check_leaks will be automatically called on
* program exit.
*/
bool new_autocheck_flag = true;
/**
* Flag to control whether verbose messages are output.
*/
bool new_verbose_flag = false;
/**
* Pointer to the output stream. The default output is \e stderr, and
* one may change it to a user stream if needed (say, #new_verbose_flag
* is \c true and there are a lot of (de)allocations).
*/
FILE* new_output_fp = stderr;
/**
* Pointer to the program name. Its initial value is the macro
* #_DEBUG_NEW_PROGNAME. You should try to assign the program path to
* it early in your application. Assigning <code>argv[0]</code> to it
* in \e main is one way. If you use \e bash or \e ksh (or similar),
* the following statement is probably what you want:
* `<code>new_progname = getenv("_");</code>'.
*/
const char* new_progname = _DEBUG_NEW_PROGNAME;
#if _DEBUG_NEW_TAILCHECK
/**
* Checks whether the padding bytes at the end of a memory block is
* tampered with.
*
* @param ptr pointer to a new_ptr_list_t struct
* @return \c true if the padding bytes are untouched; \c false
* otherwise
*/
static bool check_tail(new_ptr_list_t* ptr)
{
const unsigned char* const pointer = (unsigned char*)ptr +
ALIGNED_LIST_ITEM_SIZE + ptr->size;
for (int i = 0; i < _DEBUG_NEW_TAILCHECK; ++i)
if (pointer[i] != _DEBUG_NEW_TAILCHECK_CHAR)
return false;
return true;
}
#endif
/**
* Allocates memory and initializes control data.
*
* @param size size of the required memory block
* @param file null-terminated string of the file name
* @param line line number
* @param is_array boolean value whether this is an array operation
* @return pointer to the user-requested memory area; \c NULL
* if memory allocation is not successful
*/
static void* alloc_mem(size_t size, const char* file, int line, bool is_array)
{
assert(line >= 0);
STATIC_ASSERT((_DEBUG_NEW_ALIGNMENT & (_DEBUG_NEW_ALIGNMENT - 1)) == 0, Alignment_must_be_power_of_two);
STATIC_ASSERT(_DEBUG_NEW_TAILCHECK >= 0, Invalid_tail_check_length);
size_t s = size + ALIGNED_LIST_ITEM_SIZE + _DEBUG_NEW_TAILCHECK;
new_ptr_list_t* ptr = (new_ptr_list_t*)malloc(s);
if (ptr == NULL)
{
#if _DEBUG_NEW_STD_OPER_NEW
return NULL;
#else
fast_mutex_autolock lock(new_output_lock);
qDebug("[QxOrm] Out of memory when allocating %u bytes", size);
fflush(new_output_fp);
_DEBUG_NEW_ERROR_ACTION;
#endif
}
void* pointer = (char*)ptr + ALIGNED_LIST_ITEM_SIZE;
#if _DEBUG_NEW_FILENAME_LEN == 0
ptr->file = file;
#else
if (line)
{
QX_STRNCPY(ptr->file, file, _DEBUG_NEW_FILENAME_LEN - 1);
ptr->file[_DEBUG_NEW_FILENAME_LEN - 1] = '\0';
}
else
ptr->addr = (void*)file;
#endif
ptr->line = line;
ptr->is_array = is_array;
ptr->size = size;
ptr->magic = MAGIC;
{
fast_mutex_autolock lock(new_ptr_lock);
ptr->prev = new_ptr_list.prev;
ptr->next = &new_ptr_list;
new_ptr_list.prev->next = ptr;
new_ptr_list.prev = ptr;
}
#if _DEBUG_NEW_TAILCHECK
memset((char*)pointer + size, _DEBUG_NEW_TAILCHECK_CHAR,
_DEBUG_NEW_TAILCHECK);
#endif
if (new_verbose_flag)
{
fast_mutex_autolock lock(new_output_lock);
const char * msg_out_file = "[QxOrm] new%s: allocated %p (size %u, %s:%d)"; Q_UNUSED(msg_out_file);
const char * msg_out_no_file = "[QxOrm] new%s: allocated %p (size %u, <Unknown>)"; Q_UNUSED(msg_out_no_file);
if (line != 0) { qDebug(msg_out_file, (is_array ? "[]" : ""), pointer, size, ptr->file, ptr->line); }
#if (! _QX_MEM_LEAK_ONLY_KNOWN_SRC_FILE)
else { qDebug(msg_out_no_file, (is_array ? "[]" : ""), pointer, size); }
#endif // (! _QX_MEM_LEAK_ONLY_KNOWN_SRC_FILE)
}
total_mem_alloc += size;
return pointer;
}
/**
* Frees memory and adjusts pointers.
*
* @param pointer pointer to delete
* @param addr pointer to the caller
* @param is_array flag indicating whether it is invoked by a
* <code>delete[]</code> call
*/
void __debug_new_recorder::free_pointer(void* pointer, void* addr, bool is_array)
{
if (pointer == NULL) { return; }
new_ptr_list_t* ptr = (new_ptr_list_t*)((char*)pointer - ALIGNED_LIST_ITEM_SIZE);
if (ptr->magic != MAGIC)
{
{
fast_mutex_autolock lock(new_output_lock);
const char * msg_out = "[QxOrm] delete%s: invalid pointer %p"; Q_UNUSED(msg_out);
qDebug(msg_out, (is_array ? "[]" : ""), pointer);
}
check_mem_corruption();
fflush(new_output_fp);
_DEBUG_NEW_ERROR_ACTION;
}
if (is_array != ptr->is_array)
{
const char * msg;
if (is_array) { msg = "[QxOrm] delete[] after new"; }
else { msg = "[QxOrm] delete after new[]"; }
fast_mutex_autolock lock(new_output_lock);
const char * msg_out_file = "[QxOrm] %s: pointer %p (size %u)\n\tat %p\n\toriginally allocated at %s:%d"; Q_UNUSED(msg_out_file);
const char * msg_out_no_file = "[QxOrm] %s: pointer %p (size %u)\n\tat %p\n\toriginally allocated at <Unknown>"; Q_UNUSED(msg_out_no_file);
if (ptr->line != 0) { qDebug(msg_out_file, msg, ((char*)ptr + ALIGNED_LIST_ITEM_SIZE), ptr->size, addr, ptr->file, ptr->line); }
#if (! _QX_MEM_LEAK_ONLY_KNOWN_SRC_FILE)
else { qDebug(msg_out_no_file, msg, ((char*)ptr + ALIGNED_LIST_ITEM_SIZE), ptr->size, addr); }
#endif // (! _QX_MEM_LEAK_ONLY_KNOWN_SRC_FILE)
fflush(new_output_fp);
_DEBUG_NEW_ERROR_ACTION;
}
#if _DEBUG_NEW_TAILCHECK
if (!check_tail(ptr))
{
check_mem_corruption();
fflush(new_output_fp);
_DEBUG_NEW_ERROR_ACTION;
}
#endif
{
fast_mutex_autolock lock(new_ptr_lock);
total_mem_alloc -= ptr->size;
ptr->magic = 0;
ptr->prev->next = ptr->next;
ptr->next->prev = ptr->prev;
}
if (new_verbose_flag)
{
fast_mutex_autolock lock(new_output_lock);
const char * msg_out = "[QxOrm] delete%s: freed %p (size %u, %u bytes still allocated)"; Q_UNUSED(msg_out);
qDebug(msg_out, (is_array ? "[]" : ""), ((char*)ptr + ALIGNED_LIST_ITEM_SIZE), ptr->size, total_mem_alloc);
}
free(ptr);
return;
}
/**
* Checks for memory leaks.
*
* @return zero if no leakage is found; the number of leaks otherwise
*/
int check_leaks()
{
int leak_cnt = 0;
fast_mutex_autolock lock_ptr(new_ptr_lock);
fast_mutex_autolock lock_output(new_output_lock);
new_ptr_list_t* ptr = new_ptr_list.next;
while (ptr != &new_ptr_list)
{
const char* const pointer = (char*)ptr + ALIGNED_LIST_ITEM_SIZE;
if (ptr->magic != MAGIC)
{
const char * msg_out = "[QxOrm] warning: heap data corrupt near %p"; Q_UNUSED(msg_out);
qDebug(msg_out, pointer);
}
#if _DEBUG_NEW_TAILCHECK
if (!check_tail(ptr))
{
const char * msg_out = "[QxOrm] warning: overwritten past end of object at %p"; Q_UNUSED(msg_out);
qDebug(msg_out, pointer);
}
#endif
const char * msg_out_file = "[QxOrm] Leaked object at %p (size %u, %s:%d)"; Q_UNUSED(msg_out_file);
const char * msg_out_no_file = "[QxOrm] Leaked object at %p (size %u, <Unknown>)"; Q_UNUSED(msg_out_no_file);
if (ptr->line != 0) { qDebug(msg_out_file, pointer, ptr->size, ptr->file, ptr->line); ++leak_cnt; }
#if (! _QX_MEM_LEAK_ONLY_KNOWN_SRC_FILE)
else { qDebug(msg_out_no_file, pointer, ptr->size); ++leak_cnt; }
#endif // (! _QX_MEM_LEAK_ONLY_KNOWN_SRC_FILE)
ptr = ptr->next;
}
if (new_verbose_flag || leak_cnt)
{
const char * msg_out_leak_cnt = "[QxOrm] **** %d memory leaks found ****"; Q_UNUSED(msg_out_leak_cnt);
qDebug(msg_out_leak_cnt, leak_cnt);
}
return leak_cnt;
}
/**
* Checks for heap corruption.
*
* @return zero if no problem is found; the number of found memory
* corruptions otherwise
*/
int check_mem_corruption()
{
int corrupt_cnt = 0;
fast_mutex_autolock lock_ptr(new_ptr_lock);
fast_mutex_autolock lock_output(new_output_lock);
const char * msg_out_check_mem_start = "[QxOrm] **** Checking for memory corruption: START ****"; Q_UNUSED(msg_out_check_mem_start);
qDebug("%s", msg_out_check_mem_start);
for (new_ptr_list_t* ptr = new_ptr_list.next; ptr != &new_ptr_list; ptr = ptr->next)
{
const char* const pointer = (char*)ptr + ALIGNED_LIST_ITEM_SIZE;
if (ptr->magic == MAGIC
#if _DEBUG_NEW_TAILCHECK
&& check_tail(ptr)
#endif
)
continue;
#if _DEBUG_NEW_TAILCHECK
if (ptr->magic != MAGIC)
{
#endif
const char * msg_out_file = "[QxOrm] Heap data corrupt near %p (size %u, %s:%d)"; Q_UNUSED(msg_out_file);
const char * msg_out_no_file = "[QxOrm] Heap data corrupt near %p (size %u, <Unknown>)"; Q_UNUSED(msg_out_no_file);
if (ptr->line != 0) { qDebug(msg_out_file, pointer, ptr->size, ptr->file, ptr->line); ++corrupt_cnt; }
#if (! _QX_MEM_LEAK_ONLY_KNOWN_SRC_FILE)
else { qDebug(msg_out_no_file, pointer, ptr->size); ++corrupt_cnt; }
#endif // (! _QX_MEM_LEAK_ONLY_KNOWN_SRC_FILE)
#if _DEBUG_NEW_TAILCHECK
}
else
{
const char * msg_out_file = "[QxOrm] Overwritten past end of object at %p (size %u, %s:%d)"; Q_UNUSED(msg_out_file);
const char * msg_out_no_file = "[QxOrm] Overwritten past end of object at %p (size %u, <Unknown>)"; Q_UNUSED(msg_out_no_file);
if (ptr->line != 0) { qDebug(msg_out_file, pointer, ptr->size, ptr->file, ptr->line); ++corrupt_cnt; }
#if (! _QX_MEM_LEAK_ONLY_KNOWN_SRC_FILE)
else { qDebug(msg_out_no_file, pointer, ptr->size); ++corrupt_cnt; }
#endif // (! _QX_MEM_LEAK_ONLY_KNOWN_SRC_FILE)
}
#endif
}
const char * msg_out_check_mem_end = "[QxOrm] **** Checking for memory corruption: %d FOUND ****"; Q_UNUSED(msg_out_check_mem_end);
qDebug(msg_out_check_mem_end, corrupt_cnt);
return corrupt_cnt;
}
void __debug_new_recorder::_M_process(void* pointer)
{
if (pointer == NULL) { return; }
new_ptr_list_t* ptr = (new_ptr_list_t*)((char*)pointer - ALIGNED_LIST_ITEM_SIZE);
if (ptr->magic != MAGIC || ptr->line != 0)
{
fast_mutex_autolock lock(new_output_lock);
const char * msg_out = "[QxOrm] warning: debug_new used with placement new (%s:%d)"; Q_UNUSED(msg_out);
qDebug(msg_out, _M_file, _M_line);
return;
}
#if _DEBUG_NEW_FILENAME_LEN == 0
ptr->file = _M_file;
#else
QX_STRNCPY(ptr->file, _M_file, _DEBUG_NEW_FILENAME_LEN - 1);
ptr->file[_DEBUG_NEW_FILENAME_LEN - 1] = '\0';
#endif
ptr->line = _M_line;
}
int __debug_new_counter::_S_count = 0;
__debug_new_counter::__debug_new_counter() { ++_S_count; }
__debug_new_counter::~__debug_new_counter() { if ((--_S_count == 0) && new_autocheck_flag) { check_leaks(); } }
} // namespace memory
} // namespace qx
void* operator new(size_t size, const char* file, int line)
{
void* ptr = qx::memory::alloc_mem(size, file, line, false);
#if _DEBUG_NEW_STD_OPER_NEW
if (ptr) { return ptr; }
else { throw std::bad_alloc(); }
#else
return ptr;
#endif
}
void* operator new[](size_t size, const char* file, int line)
{
void* ptr = qx::memory::alloc_mem(size, file, line, true);
#if _DEBUG_NEW_STD_OPER_NEW
if (ptr) { return ptr; }
else { throw std::bad_alloc(); }
#else
return ptr;
#endif
}
#if HAVE_PLACEMENT_DELETE
void operator delete(void* pointer, const char* file, int line) throw()
{
if (qx::memory::new_verbose_flag)
{
qx::memory::fast_mutex_autolock lock(qx::memory::new_output_lock);
const char * msg_out = "[QxOrm] info: exception thrown on initializing object at %p (%s:%d)"; Q_UNUSED(msg_out);
qDebug(msg_out, pointer, file, line);
}
operator delete(pointer);
}
void operator delete[](void* pointer, const char* file, int line) throw()
{
if (qx::memory::new_verbose_flag)
{
qx::memory::fast_mutex_autolock lock(qx::memory::new_output_lock);
const char * msg_out = "[QxOrm] info: exception thrown on initializing objects at %p (%s:%d)"; Q_UNUSED(msg_out);
qDebug(msg_out, pointer, file, line);
}
operator delete[](pointer);
}
#endif // HAVE_PLACEMENT_DELETE
#endif // _QX_USE_MEM_LEAK_DETECTION
#endif // QT_NO_DEBUG
#endif // NDEBUG
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