fixup! Implement Socket for Windows (WIP)

src/lib_c/x86_64-windows-msvc/c/netdb.cr

@@ -3,8 +3,6 @@
 # require "./stdint"
 require "./sys/socket"
 
-#@[Link(ldflags: "WS2tcpip.obj")]
-@[Link("Kernel32")]
 lib LibC
   AI_PASSIVE     = 0x0001
   AI_CANONNAME   = 0x0002
@@ -89,6 +87,7 @@ lib LibC
   fun freeaddrinfo(pAddrInfo : PADDRINFOA) : VOID
   fun getaddrinfo(pNodeName : PCSTR, pServiceName : PCSTR, pHints : ADDRINFOA*, ppResult : PADDRINFOA*) : INT
   fun getnameinfo(pSockaddr : SOCKADDR*, sockaddrLength : SocklenT, pNodeBuffer : PCHAR, nodeBufferSize : DWORD, pServiceBuffer : PCHAR, serviceBufferSize : DWORD, flags : INT) : INT
-  #fun gai_strerror = gai_strerrorA(ecode : Int) : UInt8*
-  fun formatMessageA = FormatMessageA(dwFlags : DWORD, lpSource : LPCVOID, dwMessageId : DWORD, dwLanguageId : DWORD, lpBuffer : LPSTR, nSize : DWORD, ...) : DWORD
+
+  # fun gai_strerror = gai_strerrorA(ecode : Int) : UInt8*
+  # See src/socket/addrinfo.cr for `gai_strerrorA` function definition
 end

src/lib_c/x86_64-windows-msvc/c/sys/socket.cr

@@ -2,23 +2,24 @@ require "./types"
 
 @[Link("WS2_32")]
 lib LibC
-  alias SocklenT = UInt
+  alias SocklenT = Int
   alias SaFamilyT = UShort
+  alias SOCKET = UInt
 
   SO_REUSEADDR = 0x0004
   SO_BROADCAST = 0x0020
   SOL_SOCKET = 0xFFFF
 
+  # -2147195266 is the value after convertion to long, actual value 2147772030 with type unsigned
+  FIONBIO = -2147195266
+
   struct Sockaddr
     sa_family : SaFamilyT
-    sa_data : StaticArray(Char, 14)
+    sa_data : StaticArray(UInt8, 14)
   end
 
   alias SOCKADDR = Sockaddr
 
-  FIONBIO = -2147195266 # -2147195266 is the value after convertion to long, actual value 2147772030 with type unsigned
-
-  alias SOCKET = UInt
   fun socket(af : Int, type : Int, protocol : Int) : SOCKET
   fun bind(s : SOCKET, addr : Sockaddr*, namelen : Int) : Int
   fun closesocket(s : SOCKET) : Int
@@ -33,4 +34,4 @@ lib LibC
   fun connect(s : SOCKET, name : Sockaddr*, namelen : Int) : Int
   fun getsockname(s : SOCKET, name : Sockaddr*, namelen : Int*) : Int
   fun htons(hostshort : UShort) : UShort
-end
+end

src/lib_c/x86_64-windows-msvc/c/winbase.cr

@@ -2,6 +2,7 @@ require "c/winnt"
 require "c/win_def"
 require "c/int_safe"
 
+@[Link("Kernel32")]
 lib LibC
   fun GetLastError : DWORD
   fun SetLastError(dwErrCode : DWORD)
@@ -110,4 +111,5 @@ lib LibC
   MOVEFILE_FAIL_IF_NOT_TRACKABLE = 0x20_u32
 
   fun MoveFileExW(lpExistingFileName : LPWSTR, lpNewFileName : LPWSTR, dwFlags : DWORD) : BOOL
+  fun FormatMessageA(dwFlags : DWORD, lpSource : LPCVOID, dwMessageId : DWORD, dwLanguageId : DWORD, lpBuffer : LPSTR, nSize : DWORD, ...) : DWORD
 end

src/socket.cr

@@ -5,20 +5,6 @@ require "c/netinet/tcp"
 require "c/sys/socket"
 require "c/sys/un"
 require "io/evented"
-{% if flag?(:win32) %}
-  require "c/sys/socket"
-
-  GAI_STRERROR_BUFFER_SIZE = 1024
-
-  def gai_strerror(ecode : Int) : Bytes
-    buf = uninitialized StaticArray(UInt8, 1025)
-    lang = (0x01_u16 << 10) | 0x00_u16
-
-    LibC.formatMessageA(LibC::FORMAT_MESSAGE_FROM_SYSTEM | LibC::FORMAT_MESSAGE_IGNORE_INSERTS | LibC::FORMAT_MESSAGE_MAX_WIDTH_MASK, Pointer(LibC::DWORD).null, ecode, lang, buf, GAI_STRERROR_BUFFER_SIZE, Pointer(UInt32).null)
-
-    buf.to_slice
-  end
-{% end %}
 
 class Socket < IO
   include IO::Buffered

src/socket/addrinfo.cr

@@ -1,4 +1,5 @@
 require "uri/punycode"
+require "c/sys/socket"
 
 class Socket
   # Domain name resolver.
@@ -83,10 +84,33 @@ class Socket
       getter error_code : Int32
 
       def self.new(error_code, domain)
-        # TODO
-        # Care
-        new error_code, String.new(gai_strerror(error_code)), domain
+        new error_code, String.new(self.gai_strerror(error_code)), domain
       end
+
+      {% if flag?(:win32) %}
+        # This is the recreation of gai_strerrorA in Windows, as they
+        # define their gai_strerrorA in a C-header
+        # 
+        # See https://gist.github.com/andraantariksa/0dacbe0999427d8554286e568ee5f220#file-ws2tcpip-h-L682
+        def self.gai_strerror(ecode : Int)
+          # The buffer size defined in WS2tcpip.h is 1024 char
+          # 1024 + 1 (for null at the end of C-string) = 1025
+          buf = uninitialized StaticArray(UInt8, 1025)
+          lang = (0x01_u16 << 10) | 0x00_u16
+
+          LibC.FormatMessageA(LibC::FORMAT_MESSAGE_FROM_SYSTEM |
+            LibC::FORMAT_MESSAGE_IGNORE_INSERTS |
+            LibC::FORMAT_MESSAGE_MAX_WIDTH_MASK,
+            Pointer(LibC::DWORD).null, ecode, lang, buf, 1024, Pointer(UInt32).null)
+
+          buf.to_slice
+        end
+      {% else %}
+        @[AlwaysInline]
+        def self.gai_strerror(ecode : Int)
+          LibC::gai_strerror(ecode)
+        end
+      {% end %}
 
       def initialize(@error_code, message, domain)
         super("Hostname lookup for #{domain} failed: #{message}")