USB: add usb network redirection support

This patch adds support for a usb-redir device, which takes a chardev
as a communication channel to an actual usbdevice using the usbredir protocol.

Compiling the usb-redir device requires usbredir-0.3 to be installed for
the usbredir protocol parser, usbredir-0.3 also contains a server for
redirecting usb traffic from an actual usb device. You can get the 0.3
release of usbredir here:
http://people.fedoraproject.org/~jwrdegoede/usbredir-0.3.tar.bz2
(getting a more formal site for it is a WIP)

Example usage:
1) Start usbredirserver for a usb device:
sudo usbredirserver 045e:0772
2) Start qemu with usb2 support + a chardev talking to usbredirserver +
   a usb-redir device using this chardev:
qemu ... \
  -readconfig docs/ich9-ehci-uhci.cfg \
  -chardev socket,id=usbredirchardev,host=localhost,port=4000 \
  -device usb-redir,chardev=usbredirchardev,id=usbredirdev

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
diff --git a/configure b/configure
index e57efb1..3a76bb8 100755
--- a/configure
+++ b/configure
@@ -177,6 +177,7 @@
 rbd=""
 smartcard=""
 smartcard_nss=""
+usb_redir=""
 opengl=""
 
 # parse CC options first
@@ -743,6 +744,10 @@
   ;;
   --enable-smartcard-nss) smartcard_nss="yes"
   ;;
+  --disable-usb-redir) usb_redir="no"
+  ;;
+  --enable-usb-redir) usb_redir="yes"
+  ;;
   *) echo "ERROR: unknown option $opt"; show_help="yes"
   ;;
   esac
@@ -1018,6 +1023,8 @@
 echo "  --enable-smartcard       enable smartcard support"
 echo "  --disable-smartcard-nss  disable smartcard nss support"
 echo "  --enable-smartcard-nss   enable smartcard nss support"
+echo "  --disable-usb-redir      disable usb network redirection support"
+echo "  --enable-usb-redir       enable usb network redirection support"
 echo ""
 echo "NOTE: The object files are built at the place where configure is launched"
 exit 1
@@ -2371,6 +2378,22 @@
     smartcard_nss="no"
 fi
 
+# check for usbredirparser for usb network redirection support
+if test "$usb_redir" != "no" ; then
+    if $pkg_config libusbredirparser >/dev/null 2>&1 ; then
+        usb_redir="yes"
+        usb_redir_cflags=$($pkg_config --cflags libusbredirparser 2>/dev/null)
+        usb_redir_libs=$($pkg_config --libs libusbredirparser 2>/dev/null)
+        QEMU_CFLAGS="$QEMU_CFLAGS $usb_redir_cflags"
+        LIBS="$LIBS $usb_redir_libs"
+    else
+        if test "$usb_redir" = "yes"; then
+            feature_not_found "usb-redir"
+        fi
+        usb_redir="no"
+    fi
+fi
+
 ##########################################
 
 ##########################################
@@ -2617,6 +2640,7 @@
 echo "rbd support       $rbd"
 echo "xfsctl support    $xfs"
 echo "nss used          $smartcard_nss"
+echo "usb net redir     $usb_redir"
 echo "OpenGL support    $opengl"
 
 if test $sdl_too_old = "yes"; then
@@ -2910,6 +2934,10 @@
   echo "CONFIG_SMARTCARD_NSS=y" >> $config_host_mak
 fi
 
+if test "$usb_redir" = "yes" ; then
+  echo "CONFIG_USB_REDIR=y" >> $config_host_mak
+fi
+
 if test "$opengl" = "yes" ; then
   echo "CONFIG_OPENGL=y" >> $config_host_mak
 fi