[Qemu-devel] [PATCH v4 1/2] configure: Default to enable module build

[Fam Zheng <famz@redhat.com>]

We have module build support around for a while, but also had it bitrot
several times. It probably makes sense to enable it by default so that
people can notice and use it.

Add --disable-modules as a counterpart to --enable-modules, which is
now turned on by default.  If both are omitted, support is guessed as
usual.

pie is now checked for all platforms, because it's depended on by module
build.

Signed-off-by: Fam Zheng <famz@redhat.com>
---
 configure | 126 +++++++++++++++++++++++++++++++++++++++++---------------------
 1 file changed, 83 insertions(+), 43 deletions(-)

diff --git a/configure b/configure
index f185dd0..803bb2e 100755
--- a/configure
+++ b/configure
@@ -271,7 +271,7 @@ gcov_tool="gcov"
 EXESUF=""
 DSOSUF=".so"
 LDFLAGS_SHARED="-shared"
-modules="no"
+modules=""
 prefix="/usr/local"
 mandir="\${prefix}/share/man"
 datadir="\${prefix}/share"
@@ -768,6 +768,9 @@ for opt do
   --enable-modules)
       modules="yes"
   ;;
+  --disable-modules)
+      modules="no"
+  ;;
   --cpu=*)
   ;;
   --target-list=*) target_list="$optarg"
@@ -1259,7 +1262,8 @@ Advanced options (experts only):
   --sysconfdir=PATH        install config in PATH$confsuffix
   --localstatedir=PATH     install local state in PATH (set at runtime on win32)
   --with-confsuffix=SUFFIX suffix for QEMU data inside datadir/libdir/sysconfdir [$confsuffix]
-  --enable-modules         enable modules support
+  --enable-modules         enable modules support (default)
+  --disable-modules        enable modules support
   --enable-debug-tcg       enable TCG debugging
   --disable-debug-tcg      disable TCG debugging (default)
   --enable-debug-info      enable debugging information (default)
@@ -1532,9 +1536,6 @@ if compile_prog "-Werror -fno-gcse" "" ; then
 fi
 
 if test "$static" = "yes" ; then
-  if test "$modules" = "yes" ; then
-    error_exit "static and modules are mutually incompatible"
-  fi
   if test "$pie" = "yes" ; then
     error_exit "static and pie are mutually incompatible"
   else
@@ -1542,16 +1543,6 @@ if test "$static" = "yes" ; then
   fi
 fi
 
-if test "$pie" = ""; then
-  case "$cpu-$targetos" in
-    i386-Linux|x86_64-Linux|x32-Linux|i386-OpenBSD|x86_64-OpenBSD)
-      ;;
-    *)
-      pie="no"
-      ;;
-  esac
-fi
-
 if test "$pie" != "no" ; then
   cat > $TMPC << EOF
 
@@ -2725,22 +2716,25 @@ if test "$mingw32" = yes; then
 else
     glib_req_ver=2.12
 fi
-glib_modules=gthread-2.0
-if test "$modules" = yes; then
-    glib_modules="$glib_modules gmodule-2.0"
-fi
 
-for i in $glib_modules; do
-    if $pkg_config --atleast-version=$glib_req_ver $i; then
-        glib_cflags=`$pkg_config --cflags $i`
-        glib_libs=`$pkg_config --libs $i`
-        CFLAGS="$glib_cflags $CFLAGS"
-        LIBS="$glib_libs $LIBS"
-        libs_qga="$glib_libs $libs_qga"
-    else
-        error_exit "glib-$glib_req_ver $i is required to compile QEMU"
-    fi
-done
+glib_pkg_config()
+{
+  if $pkg_config --atleast-version=$glib_req_ver $1; then
+    local probe_cflags=$($pkg_config --cflags $1)
+    local probe_libs=$($pkg_config --libs $1)
+    CFLAGS="$probe_cflags $CFLAGS"
+    LIBS="$probe_libs $LIBS"
+    libs_qga="$probe_libs $libs_qga"
+    glib_cflags="$probe_cflags $glib_cflags"
+    glib_libs="$probe_libs $glib_libs"
+    return 0
+  else
+    return 1
+  fi
+}
+
+glib_pkg_config gthread-2.0 || \
+  error_exit "glib-$glib_req_ver gthread-2.0 is required to compile QEMU"
 
 # g_test_trap_subprocess added in 2.38. Used by some tests.
 glib_subprocess=yes
@@ -2749,19 +2743,65 @@ if ! $pkg_config --atleast-version=2.38 glib-2.0; then
 fi
 
 ##########################################
-# SHA command probe for modules
-if test "$modules" = yes; then
-    shacmd_probe="sha1sum sha1 shasum"
-    for c in $shacmd_probe; do
-        if has $c; then
-            shacmd="$c"
-            break
-        fi
-    done
-    if test "$shacmd" = ""; then
-        error_exit "one of the checksum commands is required to enable modules: $shacmd_probe"
-    fi
-fi
+# SHA command and gmodule-2.0 probe for modules
+# return 0 if probe succeeds
+# $1: true - force mode, exit if probe fail
+#     false - optoinal mode, return 1 if probe fail
+module_try_enable()
+{
+  force=$1
+  if test "$static" = "yes"; then
+    if $force; then
+      error_exit "static and modules are mutually incompatible"
+    else
+      modules="no"
+      return
+    fi
+  fi
+  shacmd_probe="sha1sum sha1 shasum"
+  for c in $shacmd_probe; do
+    if has $c; then
+      shacmd="$c"
+      break
+    fi
+  done
+  if test "$pie" = "no"; then
+    if $force; then
+      error_exit "PIE support is required to enable modules"
+    else
+      modules="no"
+      return
+    fi
+  fi
+  if test "$shacmd" = ""; then
+    if $force; then
+      error_exit "one of the checksum commands is required to enable modules: $shacmd_probe"
+    else
+      modules="no"
+      return
+    fi
+  fi
+  if ! glib_pkg_config gmodule-2.0; then
+    if $force; then
+      error_exit "glib-$glib_req_ver gmodule-2.0 is required to compile QEMU"
+    else
+      modules="no"
+      return
+    fi
+  fi
+  modules="yes"
+}
+
+case "$modules" in
+  yes)
+    module_try_enable true
+    ;;
+  "")
+    module_try_enable false
+    ;;
+  no)
+    ;;
+esac
 
 ##########################################
 # pixman support probe
-- 
1.9.3