[Qemu-devel] [PULL v2 09/20] configure: Default to enable module build

[Paolo Bonzini <pbonzini@redhat.com>]

From: 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>
Message-Id: <1423481144-20314-2-git-send-email-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 .travis.yml |   2 +-
 configure   | 123 +++++++++++++++++++++++++++++++++++++++++-------------------
 2 files changed, 86 insertions(+), 39 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index 0ac170b..12bf1db 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -99,5 +99,5 @@ matrix:
           EXTRA_CONFIG="--enable-trace-backends=ust"
       compiler: gcc
     - env: TARGETS=i386-softmmu,x86_64-softmmu
-           EXTRA_CONFIG="--enable-modules"
+           EXTRA_CONFIG="--disable-modules"
       compiler: gcc
diff --git a/configure b/configure
index 704b34c..6faeb00 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"
@@ -784,6 +784,9 @@ for opt do
   --enable-modules)
       modules="yes"
   ;;
+  --disable-modules)
+      modules="no"
+  ;;
   --cpu=*)
   ;;
   --target-list=*) target_list="$optarg"
@@ -1508,9 +1511,6 @@ 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 "$pie" = "yes" ; then
     error_exit "static and pie are mutually incompatible"
   else
@@ -1518,17 +1518,6 @@ if test "$static" = "yes" ; then
   fi
 fi
 
-# Unconditional check for compiler __thread support
-  cat > $TMPC << EOF
-static __thread int tls_var;
-int main(void) { return tls_var; }
-EOF
-
-if ! compile_prog "-Werror" "" ; then
-    error_exit "Your compiler does not support the __thread specifier for " \
-	"Thread-Local Storage (TLS). Please upgrade to a version that does."
-fi
-
 if test "$pie" = ""; then
   case "$cpu-$targetos" in
     i386-Linux|x86_64-Linux|x32-Linux|i386-OpenBSD|x86_64-OpenBSD)
@@ -1601,6 +1590,17 @@ EOF
   fi
 fi
 
+# Unconditional check for compiler __thread support
+  cat > $TMPC << EOF
+static __thread int tls_var;
+int main(void) { return tls_var; }
+EOF
+
+if ! compile_prog "-Werror" "" ; then
+    error_exit "Your compiler does not support the __thread specifier for " \
+	"Thread-Local Storage (TLS). Please upgrade to a version that does."
+fi
+
 ##########################################
 # __sync_fetch_and_and requires at least -march=i486. Many toolchains
 # use i686 as default anyway, but for those that don't, an explicit
@@ -2784,17 +2784,26 @@ if test "$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 $1; then
+    local probe_cflags
+    local probe_libs
+    probe_cflags=$($pkg_config --cflags $1)
+    probe_libs=$($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
@@ -2815,19 +2824,57 @@ if ! compile_prog "$glib_cflags -Werror" "$glib_libs" ; 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"
+# 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
+  fi
+  shacmd_probe="sha1sum sha1 shasum"
+  for c in $shacmd_probe; do
+    if has $c; then
+      shacmd="$c"
+      break
+    fi
+  done
+  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
-- 
2.4.3