typedef struct 
{
       int length;
       int pos;
       void *data;
} MEMFILE;


unsigned int memopen(char *name)
{
       MEMFILE *memfile;

       memfile = (MEMFILE *)calloc(sizeof(MEMFILE),1);
       {       
              HRSRC              rec;
              HGLOBAL              handle;

              rec = FindResource(NULL, name, "BGM");
              handle = LoadResource(NULL, rec);
              
              memfile->data = LockResource(handle);
              memfile->length = SizeofResource(NULL, rec);
              memfile->pos = 0;
       }
       return (unsigned int)memfile;
}

void memclose(unsigned int handle)
{
       MEMFILE *memfile = (MEMFILE *)handle;
       free(memfile);
}

int memread(void *buffer, int size, unsigned int handle)
{
       MEMFILE *memfile = (MEMFILE *)handle;

       if (memfile->pos + size >= memfile->length)
              size = memfile->length - memfile->pos;

       memcpy(buffer, (char *)memfile->data+memfile->pos, size);
       memfile->pos += size;
       
       return size;
}

void memseek(unsigned int handle, int pos, signed char mode)
{
       MEMFILE *memfile = (MEMFILE *)handle;

       if (mode == SEEK_SET) 
              memfile->pos = pos;
       else if (mode == SEEK_CUR) 
              memfile->pos += pos;
       else if (mode == SEEK_END)
              memfile->pos = memfile->length + pos;

       if (memfile->pos > memfile->length)
              memfile->pos = memfile->length;
}

int memtell(unsigned int handle)
{
       MEMFILE *memfile = (MEMFILE *)handle;

       return memfile->pos;
}

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