// 
// __crt_mbstring::__c16rtomb_utf8 from 0x18013d8c4 to 0x18013d967 (163 bytes)
// 
// 3 xrefs:
// > __crt_mbstring::__wcsrtombs_utf8 @ 0x180137164
// > __crt_mbstring::__wcsrtombs_utf8 @ 0x1801371d8
// > <???> @ 0x180203ae8
// 
// 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
// 

unsigned __int64 __fastcall __crt_mbstring::__c16rtomb_utf8(
        __crt_mbstring *this,
        char *a2,
        _DWORD *a3,
        struct _Mbstatet *a4)
{
  struct _Mbstatet *v4; // r9
  _DWORD *v5; // rbx
  unsigned __int16 v6; // dx
  unsigned __int64 result; // rax
  char *v8; // rdx
  __int64 v9; // [rsp+40h] [rbp+18h] BYREF

  v4 = (struct _Mbstatet *)(unsigned __int16)a2;
  v5 = &unk_1801F5728;
  if ( a3 )
    v5 = a3;
  v6 = (_WORD)a2 + 9216;
  if ( *v5 )
  {
    if ( v6 > 0x3FFu )
      goto LABEL_5;
    v9 = 0;
    result = __crt_mbstring::__c32rtomb_utf8(this, (char *)(*v5 + ((unsigned int)v4 & 0xFFFF23FF)), (char32_t)&v9, v4);
    *(_QWORD *)v5 = 0;
  }
  else
  {
    if ( v6 <= 0x3FFu )
    {
LABEL_5:
      *(_QWORD *)v5 = 0;
      *errno() = 42;
      return -1;
    }
    v8 = (char *)(unsigned int)v4;
    LOWORD(v4) = (_WORD)v4 + 10240;
    if ( (unsigned __int16)v4 > 0x3FFu )
    {
      return __crt_mbstring::__c32rtomb_utf8(this, v8, (char32_t)v5, v4);
    }
    else
    {
      *v5 = (((_DWORD)v8 << 10) & 0xFC9FFC00) + 0x10000;
      return 0;
    }
  }
  return result;
}