winamp/Src/ns-eel/megabuf.c

#include <windows.h>
#include "../ns-eel/ns-eel.h"
#include "../ns-eel/ns-eel-int.h"
#include "megabuf.h"

void megabuf_ppproc(void *data, int data_size, void **userfunc_data)
{
  if (data_size > 5 && *(int*)((char *)data+1) == 0xFFFFFFFF)
  {
    *(int*)((char *)data+1) = (int) (userfunc_data+0);
  }
}

void megabuf_cleanup(NSEEL_VMCTX ctx)
{
  if (ctx)
  {
    compileContext *c=(compileContext*)ctx;
    if (c->userfunc_data[0])
    {
      double **blocks = (double **)c->userfunc_data[0];
      int x;
      for (x = 0; x < MEGABUF_BLOCKS; x ++)
      {
        if (blocks[x]) VirtualFree(blocks[x], 0/*sizeof(double)*MEGABUF_ITEMSPERBLOCK*/, MEM_RELEASE);
					//GlobalFree(blocks[x]);
        blocks[x]=0;
      }
			VirtualFree(blocks, 0/*sizeof(double *)*MEGABUF_BLOCKS*/, MEM_RELEASE);
      //GlobalFree((HGLOBAL)blocks);
      c->userfunc_data[0]=0;
    }
  }
}

static double * NSEEL_CGEN_CALL megabuf_(double ***blocks, double *which)
{
  static double error;
  int w=(int)(*which + 0.0001);
  int whichblock = w/MEGABUF_ITEMSPERBLOCK;

  if (!*blocks)
  {
    *blocks = (double **)VirtualAlloc(NULL, sizeof(double *)*MEGABUF_BLOCKS, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
			//GlobalAlloc(GPTR,sizeof(double *)*MEGABUF_BLOCKS);
  }
  if (!*blocks) return &error;

  if (w >= 0 && whichblock >= 0 && whichblock < MEGABUF_BLOCKS)
  {
    int whichentry = w%MEGABUF_ITEMSPERBLOCK;
    if (!(*blocks)[whichblock])
    {
      (*blocks)[whichblock]=(double *)VirtualAlloc(NULL, sizeof(double)*MEGABUF_ITEMSPERBLOCK, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
				//GlobalAlloc(GPTR,sizeof(double)*MEGABUF_ITEMSPERBLOCK);
    }
    if ((*blocks)[whichblock])
      return &(*blocks)[whichblock][whichentry];
  }

  return &error;
}

static double * (NSEEL_CGEN_CALL *__megabuf)(double ***,double *) = &megabuf_;
__declspec ( naked ) void _asm_megabuf(void)
{
  double ***my_ctx;
  double *parm_a, *__nextBlock;
  __asm { mov edx, 0xFFFFFFFF }
  __asm { mov ebp, esp }
  __asm { sub esp, __LOCAL_SIZE }
  __asm { mov dword ptr my_ctx, edx }
  __asm { mov dword ptr parm_a, eax }
  
  __nextBlock = __megabuf(my_ctx,parm_a);

  __asm { mov eax, __nextBlock } // this is custom, returning pointer
  __asm { mov esp, ebp }
}
__declspec ( naked ) void _asm_megabuf_end(void) {}