/*
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): Brecht Van Lommel
 *                 Campbell Barton
 *
 * ***** END GPL LICENSE BLOCK *****
 */

/**
 * \file MEM_guardedalloc.h
 * \ingroup MEM
 *
 * \author Copyright (C) 2001 NaN Technologies B.V.
 * \brief Read \ref MEMPage
 *
 * \page MEMPage Guarded memory(de)allocation
 *
 * \section aboutmem c-style guarded memory allocation
 *
 * \subsection memabout About the MEM module
 *
 * MEM provides guarded malloc/calloc calls. All memory is enclosed by
 * pads, to detect out-of-bound writes. All blocks are placed in a
 * linked list, so they remain reachable at all times. There is no
 * back-up in case the linked-list related data is lost.
 *
 * \subsection memissues Known issues with MEM
 *
 * There are currently no known issues with MEM. Note that there is a
 * second intern/ module with MEM_ prefix, for use in c++.
 * 
 * \subsection memdependencies Dependencies
 * - stdlib
 * - stdio
 * 
 * \subsection memdocs API Documentation
 * See \ref MEM_guardedalloc.h
 */

#ifndef __MEM_GUARDEDALLOC_H__
#define __MEM_GUARDEDALLOC_H__

#include <stdio.h>          /* needed for FILE* */

/* needed for uintptr_t and attributes, exception, dont use BLI anywhere else in MEM_* */
#include "../../source/blender/blenlib/BLI_sys_types.h"
#include "../../source/blender/blenlib/BLI_compiler_attrs.h"

#ifdef __cplusplus
extern "C" {
#endif

	/** Returns the length of the allocated memory segment pointed at
	 * by vmemh. If the pointer was not previously allocated by this
	 * module, the result is undefined.*/
	extern size_t (*MEM_allocN_len)(const void *vmemh) ATTR_WARN_UNUSED_RESULT;

	/**
	 * Release memory previously allocated by this module.
	 */
	extern void (*MEM_freeN)(void *vmemh);

#if 0  /* UNUSED */
	/**
	 * Return zero if memory is not in allocated list
	 */
	extern short (*MEM_testN)(void *vmemh);
#endif

	/**
	 * Duplicates a block of memory, and returns a pointer to the
	 * newly allocated block.  */
	extern void *(*MEM_dupallocN)(const void *vmemh) /* ATTR_MALLOC */ ATTR_WARN_UNUSED_RESULT;

	/**
	 * Reallocates a block of memory, and returns pointer to the newly
	 * allocated block, the old one is freed. this is not as optimized
	 * as a system realloc but just makes a new allocation and copies
	 * over from existing memory. */
	extern void *(*MEM_reallocN_id)(void *vmemh, size_t len, const char *str) /* ATTR_MALLOC */ ATTR_WARN_UNUSED_RESULT ATTR_ALLOC_SIZE(2);

	/**
	 * A variant of realloc which zeros new bytes
	 */
	extern void *(*MEM_recallocN_id)(void *vmemh, size_t len, const char *str) /* ATTR_MALLOC */ ATTR_WARN_UNUSED_RESULT ATTR_ALLOC_SIZE(2);

#define MEM_reallocN(vmemh, len) MEM_reallocN_id(vmemh, len, __func__)
#define MEM_recallocN(vmemh, len) MEM_recallocN_id(vmemh, len, __func__)

	/**
	 * Allocate a block of memory of size len, with tag name str. The
	 * memory is cleared. The name must be static, because only a
	 * pointer to it is stored ! */
	extern void *(*MEM_callocN)(size_t len, const char *str) /* ATTR_MALLOC */ ATTR_WARN_UNUSED_RESULT ATTR_ALLOC_SIZE(1) ATTR_NONNULL(2);

	/**
	 * Allocate a block of memory of size (len * size), with tag name
	 * str, aborting in case of integer overflows to prevent vulnerabilities.
	 * The memory is cleared. The name must be static, because only a
	 * pointer to it is stored ! */
	extern void *(*MEM_calloc_arrayN)(size_t len, size_t size, const char *str) /* ATTR_MALLOC */ ATTR_WARN_UNUSED_RESULT ATTR_ALLOC_SIZE(1,2) ATTR_NONNULL(3);

	/**
	 * Allocate a block of memory of size len, with tag name str. The
	 * name must be a static, because only a pointer to it is stored !
	 * */
	extern void *(*MEM_mallocN)(size_t len, const char *str) /* ATTR_MALLOC */ ATTR_WARN_UNUSED_RESULT ATTR_ALLOC_SIZE(1) ATTR_NONNULL(2);

	/**
	 * Allocate a block of memory of size (len * size), with tag name str,
	 * aborting in case of integer overflow to prevent vulnerabilities. The
	 * name must be a static, because only a pointer to it is stored !
	 * */
	extern void *(*MEM_malloc_arrayN)(size_t len, size_t size, const char *str) /* ATTR_MALLOC */ ATTR_WARN_UNUSED_RESULT ATTR_ALLOC_SIZE(1,2) ATTR_NONNULL(3);

	/**
	 * Allocate an aligned block of memory of size len, with tag name str. The
	 * name must be a static, because only a pointer to it is stored !
	 * */
	extern void *(*MEM_mallocN_aligned)(size_t len, size_t alignment, const char *str) /* ATTR_MALLOC */ ATTR_WARN_UNUSED_RESULT ATTR_ALLOC_SIZE(1) ATTR_NONNULL(3);

	/**
	 * Same as callocN, clears memory and uses mmap (disk cached) if supported.
	 * Can be free'd with MEM_freeN as usual.
	 * */
	extern void *(*MEM_mapallocN)(size_t len, const char *str) /* ATTR_MALLOC */ ATTR_WARN_UNUSED_RESULT ATTR_ALLOC_SIZE(1) ATTR_NONNULL(2);

	/** Print a list of the names and sizes of all allocated memory
	 * blocks. as a python dict for easy investigation */ 
	extern void (*MEM_printmemlist_pydict)(void);

	/** Print a list of the names and sizes of all allocated memory
	 * blocks. */ 
	extern void (*MEM_printmemlist)(void);

	/** calls the function on all allocated memory blocks. */
	extern void (*MEM_callbackmemlist)(void (*func)(void *));

	/** Print statistics about memory usage */
	extern void (*MEM_printmemlist_stats)(void);
	
	/** Set the callback function for error output. */
	extern void (*MEM_set_error_callback)(void (*func)(const char *));

	/**
	 * Are the start/end block markers still correct ?
	 *
	 * @retval 0 for correct memory, 1 for corrupted memory. */
	extern bool (*MEM_check_memory_integrity)(void);

	/** Set thread locking functions for safe memory allocation from multiple
	 * threads, pass NULL pointers to disable thread locking again. */
	extern void (*MEM_set_lock_callback)(void (*lock)(void), void (*unlock)(void));
	
	/** Attempt to enforce OSX (or other OS's) to have malloc and stack nonzero */
	extern void (*MEM_set_memory_debug)(void);

	/**
	 * Memory usage stats
	 * - MEM_get_memory_in_use is all memory
	 * - MEM_get_mapped_memory_in_use is a subset of all memory */
	extern size_t (*MEM_get_memory_in_use)(void);
	/** Get mapped memory usage. */
	extern size_t (*MEM_get_mapped_memory_in_use)(void);
	/** Get amount of memory blocks in use. */
	extern unsigned int (*MEM_get_memory_blocks_in_use)(void);

	/** Reset the peak memory statistic to zero. */
	extern void (*MEM_reset_peak_memory)(void);

	/** Get the peak memory usage in bytes, including mmap allocations. */
	extern size_t (*MEM_get_peak_memory)(void) ATTR_WARN_UNUSED_RESULT;

#ifdef __GNUC__
#define MEM_SAFE_FREE(v) do { \
	typeof(&(v)) _v = &(v); \
	if (*_v) { \
		MEM_freeN(*_v); \
		*_v = NULL; \
	} \
} while (0)
#else
#define MEM_SAFE_FREE(v) do { \
	void ** _v = (void **)&(v); \
	if (*_v) { \
		MEM_freeN(*_v); \
		*_v = NULL; \
	} \
} while (0)
#endif

/* overhead for lockfree allocator (use to avoid slop-space) */
#define MEM_SIZE_OVERHEAD sizeof(size_t)
#define MEM_SIZE_OPTIMAL(size) ((size) - MEM_SIZE_OVERHEAD)

#ifndef NDEBUG
extern const char *(*MEM_name_ptr)(void *vmemh);
#endif

/* Switch allocator to slower but fully guarded mode. */
void MEM_use_guarded_allocator(void);

#ifdef __cplusplus
/* alloc funcs for C++ only */
#define MEM_CXX_CLASS_ALLOC_FUNCS(_id)                                        \
public:                                                                       \
	void *operator new(size_t num_bytes) {                                    \
		return MEM_mallocN(num_bytes, _id);                                   \
	}                                                                         \
	void operator delete(void *mem) {                                         \
		if (mem)                                                              \
			MEM_freeN(mem);                                                   \
	}                                                                         \
	void *operator new[](size_t num_bytes) {                                  \
		return MEM_mallocN(num_bytes, _id "[]");                              \
	}                                                                         \
	void operator delete[](void *mem) {                                       \
		if (mem)                                                              \
			MEM_freeN(mem);                                                   \
	}                                                                         \

#if defined __GNUC__ || defined __sun
#  define OBJECT_GUARDED_NEW(type, args ...) \
	new(MEM_mallocN(sizeof(type), __func__)) type(args)
#else
#  define OBJECT_GUARDED_NEW(type, ...) \
	new(MEM_mallocN(sizeof(type), __FUNCTION__)) type(__VA_ARGS__)
#endif
#define OBJECT_GUARDED_DELETE(what, type) \
	{ if(what) { \
			((type*)(what))->~type(); \
			MEM_freeN(what); \
	} } (void)0
#endif  /* __cplusplus */

#ifdef __cplusplus
}
#endif  /* __cplusplus */

#endif  /* __MEM_GUARDEDALLOC_H__ */
