dlmalloc.c

#include <common.h>

#if defined(CONFIG_UNIT_TEST)
#define DEBUG
#endif

#include <malloc.h>
#include <asm/io.h>

#ifdef DEBUG
#if __STD_C
static void malloc_update_mallinfo (void);
void malloc_stats (void);
#else
static void malloc_update_mallinfo ();
void malloc_stats();
#endif
#endif	/* DEBUG */

DECLARE_GLOBAL_DATA_PTR;

/*
  Emulation of sbrk for WIN32
  All code within the ifdef WIN32 is untested by me.

  Thanks to Martin Fong and others for supplying this.
*/


#ifdef WIN32

#define AlignPage(add) (((add) + (malloc_getpagesize-1)) & \
~(malloc_getpagesize-1))
#define AlignPage64K(add) (((add) + (0x10000 - 1)) & ~(0x10000 - 1))

/* resrve 64MB to insure large contiguous space */
#define RESERVED_SIZE (1024*1024*64)
#define NEXT_SIZE (2048*1024)
#define TOP_MEMORY ((unsigned long)2*1024*1024*1024)

struct GmListElement;
typedef struct GmListElement GmListElement;

struct GmListElement
{
	GmListElement* next;
	void* base;
};

static GmListElement* head = 0;
static unsigned int gNextAddress = 0;
static unsigned int gAddressBase = 0;
static unsigned int gAllocatedSize = 0;

static
GmListElement* makeGmListElement (void* bas)
{
	GmListElement* this;
	this = (GmListElement*)(void*)LocalAlloc (0, sizeof (GmListElement));
	assert (this);
	if (this)
	{
		this->base = bas;
		this->next = head;
		head = this;
	}
	return this;
}

void gcleanup ()
{
	BOOL rval;
	assert ( (head == NULL) || (head->base == (void*)gAddressBase));
	if (gAddressBase && (gNextAddress - gAddressBase))
	{
		rval = VirtualFree ((void*)gAddressBase,
							gNextAddress - gAddressBase,
							MEM_DECOMMIT);
	assert (rval);
	}
	while (head)
	{
		GmListElement* next = head->next;
		rval = VirtualFree (head->base, 0, MEM_RELEASE);
		assert (rval);
		LocalFree (head);
		head = next;
	}
}

static
void* findRegion (void* start_address, unsigned long size)
{
	MEMORY_BASIC_INFORMATION info;
	if (size >= TOP_MEMORY) return NULL;

	while ((unsigned long)start_address + size < TOP_MEMORY)
	{
		VirtualQuery (start_address, &info, sizeof (info));
		if ((info.State == MEM_FREE) && (info.RegionSize >= size))
			return start_address;
		else
		{
			/* Requested region is not available so see if the */
			/* next region is available.  Set 'start_address' */
			/* to the next region and call 'VirtualQuery()' */
			/* again. */

			start_address = (char*)info.BaseAddress + info.RegionSize;

			/* Make sure we start looking for the next region */
			/* on the *next* 64K boundary.  Otherwise, even if */
			/* the new region is free according to */
			/* 'VirtualQuery()', the subsequent call to */
			/* 'VirtualAlloc()' (which follows the call to */
			/* this routine in 'wsbrk()') will round *down* */
			/* the requested address to a 64K boundary which */
			/* we already know is an address in the */
			/* unavailable region.  Thus, the subsequent call */
			/* to 'VirtualAlloc()' will fail and bring us back */
			/* here, causing us to go into an infinite loop. */

			start_address =
				(void *) AlignPage64K((unsigned long) start_address);
		}
	}
	return NULL;

}


void* wsbrk (long size)
{
	void* tmp;
	if (size > 0)
	{
		if (gAddressBase == 0)
		{
			gAllocatedSize = max (RESERVED_SIZE, AlignPage (size));
			gNextAddress = gAddressBase =
				(unsigned int)VirtualAlloc (NULL, gAllocatedSize,
											MEM_RESERVE, PAGE_NOACCESS);
		} else if (AlignPage (gNextAddress + size) > (gAddressBase +
gAllocatedSize))
		{
			long new_size = max (NEXT_SIZE, AlignPage (size));
			void* new_address = (void*)(gAddressBase+gAllocatedSize);
			do
			{
				new_address = findRegion (new_address, new_size);

				if (new_address == 0)
					return (void*)-1;

				gAddressBase = gNextAddress =
					(unsigned int)VirtualAlloc (new_address, new_size,
												MEM_RESERVE, PAGE_NOACCESS);
				/* repeat in case of race condition */
				/* The region that we found has been snagged */
				/* by another thread */
			}
			while (gAddressBase == 0);

			assert (new_address == (void*)gAddressBase);

			gAllocatedSize = new_size;

			if (!makeGmListElement ((void*)gAddressBase))
				return (void*)-1;
		}
		if ((size + gNextAddress) > AlignPage (gNextAddress))
		{
			void* res;
			res = VirtualAlloc ((void*)AlignPage (gNextAddress),
								(size + gNextAddress -
								 AlignPage (gNextAddress)),
								MEM_COMMIT, PAGE_READWRITE);
			if (res == 0)
				return (void*)-1;
		}
		tmp = (void*)gNextAddress;
		gNextAddress = (unsigned int)tmp + size;
		return tmp;
	}
	else if (size < 0)
	{
		unsigned int alignedGoal = AlignPage (gNextAddress + size);
		/* Trim by releasing the virtual memory */
		if (alignedGoal >= gAddressBase)
		{
			VirtualFree ((void*)alignedGoal, gNextAddress - alignedGoal,
						 MEM_DECOMMIT);
			gNextAddress = gNextAddress + size;
			return (void*)gNextAddress;
		}
		else
		{
			VirtualFree ((void*)gAddressBase, gNextAddress - gAddressBase,
						 MEM_DECOMMIT);
			gNextAddress = gAddressBase;