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int __thiscall sub_4056A0(int this, void *Src, rsize_t Dst){  unsigned int v3; // ecx@1  int v4; // ebx@1  int v5; // esi@1  int v6; // eax@2  void *v7; // ebp@4  int v8; // eax@6  int result; // eax@11  rsize_t v10; // edi@12  unsigned int v11; // eax@14  char v12; // cf@15  unsigned __int8 v13; // zf@15  void *v14; // eax@18  char v15; // cf@24  v5 = this;  v3 = *(_DWORD *)(this + 24);  v4 = v5 + 4;  if ( v3 < 0x10 )    v6 = v5 + 4;  else    v6 = *(_DWORD *)v4;  v7 = Src;  if ( (unsigned int)Src >= v6 )  {    if ( v3 < 0x10 )      v8 = v5 + 4;    else      v8 = *(_DWORD *)v4;    if ( v8 + *(_DWORD *)(v5 + 20) > (unsigned int)Src )    {      if ( v3 >= 0x10 )        v4 = *(_DWORD *)v4;      return sub_4055C0(v5, (char *)Src - v4, Dst);    }  }  v10 = Dst;  if ( Dst > 0xFFFFFFFE )    sub_55D4AF();  v11 = *(_DWORD *)(v5 + 24);  if ( v11 < v10 )  {    sub_403BD0((void *)v10, *(_DWORD *)(v5 + 20));    v12 = 0;    v13 = v10 == 0;LABEL_16:    if ( !(v12 | v13) )    {      if ( *(_DWORD *)(v5 + 24) < 0x10u )        v14 = (void *)(v5 + 4);      else        v14 = *(void **)v4;      memcpy_s(v14, *(_DWORD *)(v5 + 24), v7, v10);      v15 = *(_DWORD *)(v5 + 24) < 0x10u;      *(_DWORD *)(v5 + 20) = v10;      if ( !v15 )        v4 = *(_DWORD *)v4;      *(_BYTE *)(v4 + v10) = 0;    }    return v5;  }  v12 = 0;  v13 = v10 == 0;  if ( v10 )    goto LABEL_16;  *(_DWORD *)(v5 + 20) = v10;  if ( v11 >= 0x10 )    v4 = *(_DWORD *)v4;  result = v5;  *(_BYTE *)v4 = 0;  return result;}