// -*- Mode: C++; tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*- // vim:tabstop=4:shiftwidth=4:expandtab: /* * Copyright (C) 2004-2007 Wu Yongwei * * 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 4.12, 2007/12/31 * @author Wu Yongwei * */ #include #include #include #include #include #include #ifdef __unix__ #include #endif #ifdef _WIN32 #include #endif #include "fast_mutex.h" #include "static_assert.h" #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_CALLER_ADDRESS * * The expression to return the caller address. #print_position will * later on use this address to print the position information of memory * operation points. */ #ifndef _DEBUG_NEW_CALLER_ADDRESS #ifdef __GNUC__ #define _DEBUG_NEW_CALLER_ADDRESS __builtin_return_address(0) #else #define _DEBUG_NEW_CALLER_ADDRESS NULL #endif #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 -D_DEBUG_NEW_PROGNAME=\"a.out\" * in \e bash, or -D_DEBUG_NEW_PROGNAME=\"a.exe\" 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 * operator new 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 "debug_new.h" /** * Gets the aligned value of memory block size. */ #define align(s) \ (((s) + _DEBUG_NEW_ALIGNMENT - 1) & ~(_DEBUG_NEW_ALIGNMENT - 1)) /** * 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 operator new. */ 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 argv[0] 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: * `new_progname = getenv("_");'. */ const char* new_progname = _DEBUG_NEW_PROGNAME; #if _DEBUG_NEW_USE_ADDR2LINE /** * Tries printing the position information from an instruction address. * This is the version that uses \e addr2line. * * @param addr the instruction address to convert and print * @return \c true if the address is converted successfully (and * the result is printed); \c false if no useful * information is got (and nothing is printed) */ static bool print_position_from_addr(const void* addr) { static const void* last_addr = NULL; static char last_info[256] = ""; if (addr == last_addr) { if (last_info[0] == '\0') return false; fprintf(new_output_fp, "%s", last_info); return true; } if (new_progname) { const char addr2line_cmd[] = "addr2line -e "; #if defined(__CYGWIN__) || defined(_WIN32) const int exeext_len = 4; #else const int exeext_len = 0; #endif #if !defined(__CYGWIN__) && defined(__unix__) const char ignore_err[] = " 2>/dev/null"; #elif defined(__CYGWIN__) || \ (defined(_WIN32) && defined(WINVER) && WINVER >= 0x0500) const char ignore_err[] = " 2>nul"; #else const char ignore_err[] = ""; #endif char* cmd = (char*)alloca(strlen(new_progname) + exeext_len + sizeof addr2line_cmd - 1 + sizeof ignore_err - 1 + sizeof(void*) * 2 + 4 /* SP + "0x" + null */); strcpy(cmd, addr2line_cmd); strcpy(cmd + sizeof addr2line_cmd - 1, new_progname); size_t len = strlen(cmd); #if defined(__CYGWIN__) || defined(_WIN32) if (len <= 4 || (strcmp(cmd + len - 4, ".exe") != 0 && strcmp(cmd + len - 4, ".EXE") != 0)) { strcpy(cmd + len, ".exe"); len += 4; } #endif sprintf(cmd + len, " %p%s", addr, ignore_err); FILE* fp = popen(cmd, "r"); if (fp) { char buffer[sizeof last_info] = ""; len = 0; if (fgets(buffer, sizeof buffer, fp)) { len = strlen(buffer); if (buffer[len - 1] == '\n') buffer[--len] = '\0'; } int res = pclose(fp); // Display the file/line information only if the command // is executed successfully and the output points to a // valid position, but the result will be cached if only // the command is executed successfully. if (res == 0 && len > 0) { last_addr = addr; if (buffer[len - 1] == '0' && buffer[len - 2] == ':') last_info[0] = '\0'; else { fprintf(new_output_fp, "%s", buffer); strcpy(last_info, buffer); return true; } } } } return false; } #else /** * Tries printing the position information from an instruction address. * This is the stub version that does nothing at all. * * @return \c false always */ static bool print_position_from_addr(const void*) { return false; } #endif // _DEBUG_NEW_USE_ADDR2LINE /** * Prints the position information of a memory operation point. When \c * _DEBUG_NEW_USE_ADDR2LINE is defined to a non-zero value, this * function will try to convert a given caller address to file/line * information with \e addr2line. * * @param ptr source file name if \e line is non-zero; caller address * otherwise * @param line source line number if non-zero; indication that \e ptr * is the caller address otherwise */ static void print_position(const void* ptr, int line) { if (line != 0) // Is file/line information present? { fprintf(new_output_fp, "%s:%d", (const char*)ptr, line); } else if (ptr != NULL) // Is caller address present? { if (!print_position_from_addr(ptr)) // Fail to get source position? fprintf(new_output_fp, "%p", ptr); } else // No information is present { fprintf(new_output_fp, ""); } } /** * 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; } /** * 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); fprintf(new_output_fp, "Out of memory when allocating %u bytes\n", 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) strncpy(ptr->file, file, _DEBUG_NEW_FILENAME_LEN - 1) [_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); fprintf(new_output_fp, "new%s: allocated %p (size %u, ", is_array ? "[]" : "", pointer, size); if (line != 0) print_position(ptr->file, ptr->line); else print_position(ptr->addr, ptr->line); fprintf(new_output_fp, ")\n"); } 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 * delete[] call */ static void 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); fprintf(new_output_fp, "delete%s: invalid pointer %p (", is_array ? "[]" : "", pointer); print_position(_DEBUG_NEW_CALLER_ADDRESS, 0); fprintf(new_output_fp, ")\n"); } check_mem_corruption(); fflush(new_output_fp); _DEBUG_NEW_ERROR_ACTION; } if (is_array != ptr->is_array) { const char* msg; if (is_array) msg = "delete[] after new"; else msg = "delete after new[]"; fast_mutex_autolock lock(new_output_lock); fprintf(new_output_fp, "%s: pointer %p (size %u)\n\tat ", msg, (char*)ptr + ALIGNED_LIST_ITEM_SIZE, ptr->size); print_position(addr, 0); fprintf(new_output_fp, "\n\toriginally allocated at "); if (ptr->line != 0) print_position(ptr->file, ptr->line); else print_position(ptr->addr, ptr->line); fprintf(new_output_fp, "\n"); 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; } free(ptr); if (new_verbose_flag) { fast_mutex_autolock lock(new_output_lock); fprintf(new_output_fp, "delete%s: freed %p (size %u, %u bytes still allocated)\n", is_array ? "[]" : "", (char*)ptr + ALIGNED_LIST_ITEM_SIZE, ptr->size, total_mem_alloc); } 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) { fprintf(new_output_fp, "warning: heap data corrupt near %p\n", pointer); } #if _DEBUG_NEW_TAILCHECK if (!check_tail(ptr)) { fprintf(new_output_fp, "warning: overwritten past end of object at %p\n", pointer); } #endif fprintf(new_output_fp, "Leaked object at %p (size %u, ", pointer, ptr->size); if (ptr->line != 0) print_position(ptr->file, ptr->line); else print_position(ptr->addr, ptr->line); fprintf(new_output_fp, ")\n"); ptr = ptr->next; ++leak_cnt; } if (new_verbose_flag || leak_cnt) fprintf(new_output_fp, "*** %d leaks found\n", 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); fprintf(new_output_fp, "*** Checking for memory corruption: START\n"); 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 fprintf(new_output_fp, "Heap data corrupt near %p (size %u, ", pointer, ptr->size); #if _DEBUG_NEW_TAILCHECK } else { fprintf(new_output_fp, "Overwritten past end of object at %p (size %u, ", pointer, ptr->size); } #endif if (ptr->line != 0) print_position(ptr->file, ptr->line); else print_position(ptr->addr, ptr->line); fprintf(new_output_fp, ")\n"); ++corrupt_cnt; } fprintf(new_output_fp, "*** Checking for memory corruption: %d FOUND\n", 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); fprintf(new_output_fp, "warning: debug_new used with placement new (%s:%d)\n", _M_file, _M_line); return; } #if _DEBUG_NEW_FILENAME_LEN == 0 ptr->file = _M_file; #else strncpy(ptr->file, _M_file, _DEBUG_NEW_FILENAME_LEN - 1) [_DEBUG_NEW_FILENAME_LEN - 1] = '\0'; #endif ptr->line = _M_line; } void* operator new(size_t size, const char* file, int line) { void* ptr = 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 = 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 } void* operator new(size_t size) throw(std::bad_alloc) { return operator new(size, (char*)_DEBUG_NEW_CALLER_ADDRESS, 0); } void* operator new[](size_t size) throw(std::bad_alloc) { return operator new[](size, (char*)_DEBUG_NEW_CALLER_ADDRESS, 0); } #if !defined(__BORLANDC__) || __BORLANDC__ > 0x551 void* operator new(size_t size, const std::nothrow_t&) throw() { return alloc_mem(size, (char*)_DEBUG_NEW_CALLER_ADDRESS, 0, false); } void* operator new[](size_t size, const std::nothrow_t&) throw() { return alloc_mem(size, (char*)_DEBUG_NEW_CALLER_ADDRESS, 0, true); } #endif void operator delete(void* pointer) throw() { free_pointer(pointer, _DEBUG_NEW_CALLER_ADDRESS, false); } void operator delete[](void* pointer) throw() { free_pointer(pointer, _DEBUG_NEW_CALLER_ADDRESS, true); } #if HAVE_PLACEMENT_DELETE void operator delete(void* pointer, const char* file, int line) throw() { if (new_verbose_flag) { fast_mutex_autolock lock(new_output_lock); fprintf(new_output_fp, "info: exception thrown on initializing object at %p (", pointer); print_position(file, line); fprintf(new_output_fp, ")\n"); } operator delete(pointer); } void operator delete[](void* pointer, const char* file, int line) throw() { if (new_verbose_flag) { fast_mutex_autolock lock(new_output_lock); fprintf(new_output_fp, "info: exception thrown on initializing objects at %p (", pointer); print_position(file, line); fprintf(new_output_fp, ")\n"); } operator delete[](pointer); } void operator delete(void* pointer, const std::nothrow_t&) throw() { operator delete(pointer, (char*)_DEBUG_NEW_CALLER_ADDRESS, 0); } void operator delete[](void* pointer, const std::nothrow_t&) throw() { operator delete[](pointer, (char*)_DEBUG_NEW_CALLER_ADDRESS, 0); } #endif // HAVE_PLACEMENT_DELETE int __debug_new_counter::_S_count = 0; /** * Constructor to increment the count. */ __debug_new_counter::__debug_new_counter() { ++_S_count; } /** * Destructor to decrement the count. When the count is zero, * #check_leaks will be called. */ __debug_new_counter::~__debug_new_counter() { if (--_S_count == 0 && new_autocheck_flag) if (check_leaks()) { new_verbose_flag = true; #if defined(__GNUC__) && __GNUC__ >= 3 if (!getenv("GLIBCPP_FORCE_NEW") && !getenv("GLIBCXX_FORCE_NEW")) fprintf(new_output_fp, "*** WARNING: GCC 3 or later is detected, please make sure the\n" " environment variable GLIBCPP_FORCE_NEW (GCC 3.2 and 3.3) or\n" " GLIBCXX_FORCE_NEW (GCC 3.4 and later) is defined. Check the\n" " README file for details.\n"); #endif } }