Fix #39: getaddrinfo numeric error codes are now translated

core/src/main/scala/epollcat/internal/ch/EpollAsyncServerSocketChannel.scala

@@ -29,6 +29,7 @@ import java.net.StandardSocketOptions
 import java.nio.channels.AsynchronousServerSocketChannel
 import java.nio.channels.AsynchronousSocketChannel
 import java.nio.channels.CompletionHandler
+import java.nio.channels.UnsupportedAddressTypeException
 import java.util.concurrent.Future
 import scala.scalanative.annotation.stub
 import scala.scalanative.libc.errno
@@ -85,15 +86,37 @@ final class EpollAsyncServerSocketChannel private (fd: Int)
           hints,
           addrinfo
         )
-      if (rtn != 0)
-        throw new IOException(s"getaddrinfo: ${rtn}")
+
+      if (rtn != 0) {
+        val ex = if (rtn == posix.netdb.EAI_FAMILY) {
+          new UnsupportedAddressTypeException()
+        } else {
+          val msg = s"getaddrinfo: ${SocketHelpers.getGaiErrorMessage(rtn)}"
+          new IOException(msg)
+        }
+
+        throw ex
+      }
     }
 
     val bindRet = posix.sys.socket.bind(fd, (!addrinfo).ai_addr, (!addrinfo).ai_addrlen)
     posix.netdb.freeaddrinfo(!addrinfo)
+
+    // posix.errno.EADDRNOTAVAIL becomes available in Scala Native 0.5.0
+    val EADDRNOTAVAIL =
+      if (LinktimeInfo.isLinux) 99
+      else if (LinktimeInfo.isMac) 49
+      else Int.MaxValue // punt, will never match an errno.
+
     if (bindRet == -1) errno.errno match {
       case e if e == posix.errno.EADDRINUSE =>
         throw new BindException("Address already in use")
+      case e if e == EADDRNOTAVAIL =>
+        // Whis code may have to change when support for a new OS is added.
+        if (LinktimeInfo.isMac)
+          throw new BindException("Can't assign requested address")
+        else // Linux & a bet that an unknownd OS uses good grammer.
+          throw new BindException("Cannot assign requested address")
       case other => throw new IOException(s"bind: $other")
     }
 

core/src/main/scala/epollcat/internal/ch/EpollAsyncSocketChannel.scala

@@ -31,6 +31,7 @@ import java.nio.ByteBuffer
 import java.nio.channels.AsynchronousSocketChannel
 import java.nio.channels.ClosedChannelException
 import java.nio.channels.CompletionHandler
+import java.nio.channels.UnsupportedAddressTypeException
 import java.util.concurrent.Future
 import java.util.concurrent.TimeUnit
 import scala.annotation.tailrec
@@ -195,10 +196,18 @@ final class EpollAsyncSocketChannel private (fd: Int)
           hints,
           addrinfo
         )
-      if (rtn != 0) {
-        handler.failed(new IOException(s"getaddrinfo: $rtn"), attachment)
+      if (rtn == 0) {
+        true
+      } else {
+        val ex = if (rtn == posix.netdb.EAI_FAMILY) {
+          new UnsupportedAddressTypeException()
+        } else {
+          val msg = s"getaddrinfo: ${SocketHelpers.getGaiErrorMessage(rtn)}"
+          new IOException(msg)
+        }
+        handler.failed(ex, attachment)
         false
-      } else true
+      }
     }
 
     if (!continue)

core/src/main/scala/epollcat/internal/ch/SocketHelpers.scala

@@ -114,4 +114,9 @@ private[ch] object SocketHelpers {
     new InetSocketAddress(inetAddr, port)
   }
 
+  // Return text translation of getaddrinfo (gai) error code.
+  def getGaiErrorMessage(gaiErrorCode: CInt): String = {
+    fromCString(posix.netdb.gai_strerror(gaiErrorCode))
+  }
+
 }

core/src/main/scala/java/nio/channels/UnsupportedAddressTypeException.scala

@@ -0,0 +1,19 @@
+/*
+ * Copyright 2022 Arman Bilge
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package java.nio.channels
+
+class UnsupportedAddressTypeException extends IllegalArgumentException

tests/shared/src/test/scala/epollcat/TcpSuite.scala

@@ -164,7 +164,7 @@ class TcpSuite extends EpollcatSuite {
       .interceptMessage[ConnectException]("Connection refused")
   }
 
-  test("BindException") {
+  test("BindException - EADDRINUSE") {
     IOServerSocketChannel
       .open
       .evalTap(_.bind(new InetSocketAddress(0)))
@@ -173,6 +173,26 @@ class TcpSuite extends EpollcatSuite {
       .interceptMessage[BindException]("Address already in use")
   }
 
+  test("BindException - EADDRNOTAVAIL") {
+    // 240.0.0.1 is in reserved range 240.0.0.0/24.  Used to elicit Exception.
+    IOServerSocketChannel
+      .open
+      .use { ch =>
+        for {
+          _ <- ch.bind(new InetSocketAddress("240.0.0.1", 0))
+        } yield ()
+      }
+      .interceptMessage[BindException] {
+        val osName = System.getProperty("os.name", "unknown").toLowerCase
+        if (osName.startsWith("linux"))
+          "Cannot assign requested address"
+        else if (osName.startsWith("mac"))
+          "Can't assign requested address"
+        else
+          "unknown operating system"
+      }
+  }
+
   test("ClosedChannelException") {
     IOServerSocketChannel
       .open