// 
// sub_180003810 from 0x180003810 to 0x18000399b (395 bytes)
// 
// 8 xrefs:
// > sub_180001880 @ 0x1800018eb
// > sub_1800039A0 @ 0x180003a10
// > sub_180003A20 @ 0x180003a9d
// > cocos2d::extension::WebSocket::init @ 0x180019f15
// > <???> @ 0x18002d2b4
// > <???> @ 0x18002d2c4
// > <???> @ 0x18002d2e4
// > <???> @ 0x180049258
// 
// This function is hookable on this platform!
// 
// Using BromaIDA 8.0.0 @ https://github.com/Stazzical/BromaIDA
// Using bindings at commit ba9f177b at Thu Jul 16 22:52:06 2026 from https://github.com/geode-sdk/bindings
// 

_QWORD *__fastcall sub_180003810(_QWORD *Src, unsigned __int64 a2, __int64 a3, const void *a4, size_t Size)
{
  size_t v5; // r14
  __int64 v6; // rbx
  size_t v9; // rbp
  unsigned __int64 v10; // rdx
  unsigned __int64 v11; // r13
  __int64 v12; // rcx
  size_t v13; // rcx
  void *v14; // rax
  _QWORD *v15; // rdi
  char *v16; // r15
  _QWORD *v17; // rbx

  v5 = Src[2];
  v6 = 0x7FFFFFFFFFFFFFFFLL;
  if ( 0x7FFFFFFFFFFFFFFFLL - v5 < a2 )
    sub_180003D90();
  v9 = v5 + a2;
  v10 = (v5 + a2) | 0xF;
  v11 = Src[3];
  if ( v10 > 0x7FFFFFFFFFFFFFFFLL || (v12 = v11 >> 1, v11 > 0x7FFFFFFFFFFFFFFFLL - (v11 >> 1)) )
  {
    v13 = 0x8000000000000027uLL;
  }
  else
  {
    v6 = v10;
    if ( v10 < v12 + v11 )
      v6 = v12 + v11;
    if ( (unsigned __int64)(v6 + 1) < 0x1000 )
    {
      if ( v6 == -1 )
        v15 = nullptr;
      else
        v15 = operator new(v6 + 1);
      goto LABEL_15;
    }
    v13 = v6 + 40;
    if ( v6 + 40 < (unsigned __int64)(v6 + 1) )
      Concurrency::cancel_current_task();
  }
  v14 = operator new(v13);
  if ( !v14 )
    goto LABEL_20;
  v15 = (_QWORD *)(((unsigned __int64)v14 + 39) & 0xFFFFFFFFFFFFFFE0uLL);
  *(v15 - 1) = v14;
LABEL_15:
  Src[2] = v9;
  v16 = (char *)v15 + v5;
  Src[3] = v6;
  if ( v11 <= 0xF )
  {
    memcpy(v15, Src, v5);
    memcpy((char *)v15 + v5, a4, Size);
    v16[Size] = 0;
    goto LABEL_22;
  }
  v17 = (_QWORD *)*Src;
  memcpy(v15, (const void *)*Src, v5);
  memcpy((char *)v15 + v5, a4, Size);
  v16[Size] = 0;
  if ( v11 + 1 >= 0x1000 )
  {
    if ( (unsigned __int64)v17 - *(v17 - 1) - 8 <= 0x1F )
    {
      v17 = (_QWORD *)*(v17 - 1);
      goto LABEL_19;
    }
LABEL_20:
    invalid_parameter_noinfo_noreturn();
  }
LABEL_19:
  j_j_free(v17);
LABEL_22:
  *Src = v15;
  return Src;
}