source: vbox/trunk/src/libs/xpcom18a4/xpcom/glue/nsMemory.cpp@ 6542

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#include "nsXPCOM.h"
#include "nsMemory.h"
#include "nsXPCOMPrivate.h"

static nsIMemory* gMemory = nsnull;

static NS_METHOD FreeGlobalMemory(void)
{
    NS_ASSERTION(gMemory, "must be not null after SetupGlobalMemory");
    NS_IF_RELEASE(gMemory);
    return NS_OK;
}

#define ENSURE_ALLOCATOR \
  (gMemory ? PR_TRUE : (PRBool)(SetupGlobalMemory() != nsnull))

static nsIMemory*
SetupGlobalMemory()
{
    NS_ASSERTION(!gMemory, "must be called once");
    if (!gMemory)
    {
        NS_GetMemoryManager(&gMemory);
        NS_ASSERTION(gMemory, "can't get memory manager!");
        if (gMemory)
            NS_RegisterXPCOMExitRoutine(FreeGlobalMemory, 0);
    }
    return gMemory;
}

#ifdef XPCOM_GLUE
nsresult GlueStartupMemory() 
{
    NS_ASSERTION(!gMemory, "must be called once");
    if (!gMemory)
    {
        NS_GetMemoryManager(&gMemory);
        NS_ASSERTION(gMemory, "can't get memory manager!");
        if (!gMemory)
            return NS_ERROR_FAILURE;
    }
    return NS_OK;
}

void GlueShutdownMemory()
{
    NS_IF_RELEASE(gMemory);
}
#endif

////////////////////////////////////////////////////////////////////////////////
// nsMemory static helper routines

NS_COM void*
nsMemory::Alloc(PRSize size)
{
    if (!ENSURE_ALLOCATOR)
        return nsnull;
 
   return gMemory->Alloc(size);
}

NS_COM void*
nsMemory::Realloc(void* ptr, PRSize size)
{
    if (!ENSURE_ALLOCATOR)
        return nsnull;    

    return gMemory->Realloc(ptr, size);
}

NS_COM void
nsMemory::Free(void* ptr)
{
    if (!ENSURE_ALLOCATOR)
        return;    

    gMemory->Free(ptr);
}

NS_COM nsresult
nsMemory::HeapMinimize(PRBool aImmediate)
{
    if (!ENSURE_ALLOCATOR)
        return NS_ERROR_FAILURE;    

    return gMemory->HeapMinimize(aImmediate);
}

NS_COM void*
nsMemory::Clone(const void* ptr, PRSize size)
{
    if (!ENSURE_ALLOCATOR)
        return nsnull;    

    void* newPtr = gMemory->Alloc(size);
    if (newPtr)
        memcpy(newPtr, ptr, size);
    return newPtr;
}

NS_COM nsIMemory*
nsMemory::GetGlobalMemoryService()
{
    if (!ENSURE_ALLOCATOR)
        return nsnull;    
   
    nsIMemory* result = gMemory;
    NS_IF_ADDREF(result);
    return result;
}

//----------------------------------------------------------------------