From 2adba7d3ab073b206e64f4a5897caeddd0272c3e Mon Sep 17 00:00:00 2001
From: Jim Fehlig <jfehlig@suse.com>
Date: Tue, 17 Mar 2015 14:10:28 -0600
Subject: [PATCH] libxl: use xenlight pkgconfig file if present

xen.git commit babeca32 added a pkgconfig file for libxenlight,
allowing libxl apps to determine the location of Xen binaries
such as firmware blobs, device emulator, etc.

This patch adds support for xenlight.pc in the libxl driver, falling
back to the previous configure logic if not found.  It introduces
LIBXL_FIRMWARE_DIR and LIBXL_EXECBIN_DIR to define the firmware and
libexec_bin locations.  If xenlight.pc does not exist, the defines
are set to the current hardcoded paths.  The capabilities'
<emulator> and <loader> elements are updated to use the paths.

Signed-off-by: Jim Fehlig <jfehlig@suse.com>
---
 configure.ac           | 47 +++++++++++++++++++++++++++++-------------
 src/libxl/libxl_conf.c |  7 ++-----
 src/libxl/libxl_conf.h |  8 +++++++
 3 files changed, 43 insertions(+), 19 deletions(-)

diff --git a/configure.ac b/configure.ac
index 412a23d05f..b1193a67f3 100644
--- a/configure.ac
+++ b/configure.ac
@@ -873,24 +873,37 @@ old_LIBS="$LIBS"
 old_CFLAGS="$CFLAGS"
 LIBXL_LIBS=""
 LIBXL_CFLAGS=""
+LIBXL_FIRMWARE_DIR=""
+LIBXL_EXECBIN_DIR=""
+
 dnl search for libxl, aka libxenlight
+dnl Xen > 4.5 introduced a pkgconfig file, check for it first
 fail=0
 if test "$with_libxl" != "no" ; then
-    if test "$with_libxl" != "yes" && test "$with_libxl" != "check" ; then
-        LIBXL_CFLAGS="-I$with_libxl/include"
-        LIBXL_LIBS="-L$with_libxl"
-    fi
-    CFLAGS="$CFLAGS $LIBXL_CFLAGS"
-    LIBS="$LIBS $LIBXL_LIBS"
-    AC_CHECK_LIB([xenlight], [libxl_ctx_alloc], [
-        with_libxl=yes
-        LIBXL_LIBS="$LIBXL_LIBS -lxenlight -lxenctrl"
-    ],[
-        if test "$with_libxl" = "yes"; then
-            fail=1
+    PKG_CHECK_MODULES([LIBXL], [xenlight], [
+     LIBXL_FIRMWARE_DIR=`$PKG_CONFIG --variable xenfirmwaredir xenlight`
+     LIBXL_EXECBIN_DIR=`$PKG_CONFIG --variable libexec_bin xenlight`
+     LIBXL_LIBS="$LIBXL_LIBS -lxenctrl"
+     with_libxl=yes
+    ], [LIBXL_FOUND=no])
+    if test "$LIBXL_FOUND" = "no"; then
+        dnl No xenlight pkg-config file
+        if test "$with_libxl" != "yes" && test "$with_libxl" != "check" ; then
+            LIBXL_CFLAGS="-I$with_libxl/include"
+            LIBXL_LIBS="-L$with_libxl"
         fi
-        with_libxl=no
-    ])
+        CFLAGS="$CFLAGS $LIBXL_CFLAGS"
+        LIBS="$LIBS $LIBXL_LIBS"
+        AC_CHECK_LIB([xenlight], [libxl_ctx_alloc], [
+            with_libxl=yes
+            LIBXL_LIBS="$LIBXL_LIBS -lxenlight -lxenctrl"
+        ],[
+            if test "$with_libxl" = "yes"; then
+                fail=1
+            fi
+            with_libxl=no
+        ])
+    fi
 fi
 
 LIBS="$old_LIBS"
@@ -905,6 +918,12 @@ if test "$with_libxl" = "yes"; then
     AC_CHECK_HEADERS([libxlutil.h])
     LIBXL_LIBS="$LIBXL_LIBS -lxlutil"
     AC_DEFINE_UNQUOTED([WITH_LIBXL], 1, [whether libxenlight driver is enabled])
+    if test "x$LIBXL_FIRMWARE_DIR" != "x"; then
+        AC_DEFINE_UNQUOTED([LIBXL_FIRMWARE_DIR], ["$LIBXL_FIRMWARE_DIR"], [directory containing Xen firmware blobs])
+    fi
+    if test "x$LIBXL_EXECBIN_DIR" != "x"; then
+        AC_DEFINE_UNQUOTED([LIBXL_EXECBIN_DIR], ["$LIBXL_EXECBIN_DIR"], [directory containing Xen libexec binaries])
+    fi
 fi
 AM_CONDITIONAL([WITH_LIBXL], [test "$with_libxl" = "yes"])
 
diff --git a/src/libxl/libxl_conf.c b/src/libxl/libxl_conf.c
index 80dd5a884f..9b3c949f4c 100644
--- a/src/libxl/libxl_conf.c
+++ b/src/libxl/libxl_conf.c
@@ -305,7 +305,6 @@ libxlCapsInitGuests(libxl_ctx *ctx, virCapsPtr caps)
     regmatch_t subs[4];
     char *saveptr = NULL;
     size_t i;
-    virArch hostarch = caps->host.arch;
 
     struct guest_arch guest_archs[32];
     int nr_guest_archs = 0;
@@ -428,11 +427,9 @@ libxlCapsInitGuests(libxl_ctx *ctx, virCapsPtr caps)
         if ((guest = virCapabilitiesAddGuest(caps,
                                              guest_archs[i].hvm ? "hvm" : "xen",
                                              guest_archs[i].arch,
-                                             ((hostarch == VIR_ARCH_X86_64) ?
-                                              "/usr/lib64/xen/bin/qemu-dm" :
-                                              "/usr/lib/xen/bin/qemu-dm"),
+                                             LIBXL_EXECBIN_DIR "/qemu-system-i386",
                                              (guest_archs[i].hvm ?
-                                              "/usr/lib/xen/boot/hvmloader" :
+                                              LIBXL_FIRMWARE_DIR "/hvmloader" :
                                               NULL),
                                              1,
                                              machines)) == NULL) {
diff --git a/src/libxl/libxl_conf.h b/src/libxl/libxl_conf.h
index 5d6f87d461..59389d1296 100644
--- a/src/libxl/libxl_conf.h
+++ b/src/libxl/libxl_conf.h
@@ -55,6 +55,14 @@
 # define LIBXL_DUMP_DIR LIBXL_LIB_DIR "/dump"
 # define LIBXL_BOOTLOADER_PATH "pygrub"
 
+# ifndef LIBXL_FIRMWARE_DIR
+#  define LIBXL_FIRMWARE_DIR "/usr/lib/xen/boot"
+# endif
+# ifndef LIBXL_EXECBIN_DIR
+#  define LIBXL_EXECBIN_DIR "/usr/lib/xen/bin"
+# endif
+
+
 /* libxl interface for setting VCPU affinity changed in 4.5. In fact, a new
  * parameter has been added, representative of 'VCPU soft affinity'. If one
  * does not care about it (and that's libvirt case), passing NULL is the