Convert yajl check to use LIBVIRT_CHECK_LIB_ALT

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>

m4/virt-yajl.m4

@@ -0,0 +1,51 @@
+dnl The libyajl.so library
+dnl
+dnl Copyright (C) 2012-2013 Red Hat, Inc.
+dnl
+dnl This library is free software; you can redistribute it and/or
+dnl modify it under the terms of the GNU Lesser General Public
+dnl License as published by the Free Software Foundation; either
+dnl version 2.1 of the License, or (at your option) any later version.
+dnl
+dnl This library is distributed in the hope that it will be useful,
+dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
+dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+dnl Lesser General Public License for more details.
+dnl
+dnl You should have received a copy of the GNU Lesser General Public
+dnl License along with this library.  If not, see
+dnl <http://www.gnu.org/licenses/>.
+dnl
+
+AC_DEFUN([LIBVIRT_CHECK_YAJL],[
+  dnl YAJL JSON library http://lloyd.github.com/yajl/
+  if test "$with_qemu:$with_yajl" = yes:check; then
+    dnl Some versions of qemu require the use of yajl; try to detect them
+    dnl here, although we do not require qemu to exist in order to compile.
+    dnl This check mirrors src/qemu/qemu_capabilities.c
+    AC_PATH_PROGS([QEMU], [qemu-kvm qemu kvm qemu-system-x86_64],
+                  [], [$PATH:/usr/bin:/usr/libexec])
+    if test -x "$QEMU"; then
+      if `$QEMU -help | grep libvirt` >/dev/null; then
+        with_yajl=yes
+      else
+        [qemu_version_sed='s/.*ersion \([0-9.,]*\).*/\1/']
+        qemu_version=`$QEMU -version | sed "$qemu_version_sed"`
+        case $qemu_version in
+          [[1-9]].* | 0.15.* ) with_yajl=yes ;;
+          0.* | '' ) ;;
+          *) AC_MSG_ERROR([Unexpected qemu version string]) ;;
+        esac
+      fi
+    fi
+  fi
+
+  LIBVIRT_CHECK_LIB_ALT([YAJL], [yajl],
+                        [yajl_parse_complete], [yajl/yajl_common.h],
+                        [YAJL2], [yajl],
+                        [yajl_tree_parse], [yajl/yajl_common.h])
+])
+
+AC_DEFUN([LIBVIRT_RESULT_YAJL],[
+  LIBVIRT_RESULT_LIB([YAJL])
+])