Libguestfs - May 2018 - Re: [PATCH] java: support OpenJDK 10+

Starting OpenJDK 10, the 'javah' utility is no more provided [1], and
its functionality is provided by 'javac' itself.  Hence, do not error
out on missing 'javah', and store whether it was found; in case it is
not, then:
1) assume 'javac' has the -h parameter to generate the C header, and
   make use of it
2) tell the buildsystem that com_redhat_et_libguestfs_GuestFS.h depends
   on the JAR, since the the header is generated at the step (1)

[1] https://bugs.java.com/view_bug.do?bug_id=JDK-8182758
---
 java/Makefile.am   | 11 +++++++++++
 m4/guestfs-java.m4 |  5 ++---
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/java/Makefile.am b/java/Makefile.am
index 376d89d17..81c20f266 100644
--- a/java/Makefile.am
+++ b/java/Makefile.am
@@ -77,6 +77,9 @@ if HAVE_JAVA
 
 JAVAC_FLAGS = $(EXTRA_JAVAC_FLAGS) -encoding utf-8
 JAVADOC_FLAGS = -encoding utf-8
+if !HAVE_JAVAH
+JAVAC_FLAGS += -h .
+endif
 
 # Java source.
 
@@ -125,10 +128,18 @@ libguestfs_jni_la_LDFLAGS = -version-info
$(JNI_VERSION_INFO) -shared
 
 BUILT_SOURCES = com_redhat_et_libguestfs_GuestFS.h
 
+if HAVE_JAVAH
+
 com_redhat_et_libguestfs_GuestFS.h: $(java_prefix)/GuestFS.class
 	rm -f $@
 	$(JAVAH) -classpath $(srcdir):. com.redhat.et.libguestfs.GuestFS
 
+else
+
+com_redhat_et_libguestfs_GuestFS.h: libguestfs-${VERSION}.jar
+
+endif
+
 # Documentation.
 
 noinst_SCRIPTS = doc-stamp
diff --git a/m4/guestfs-java.m4 b/m4/guestfs-java.m4
index 9d0f948b6..2ab932ac4 100644
--- a/m4/guestfs-java.m4
+++ b/m4/guestfs-java.m4
@@ -73,9 +73,7 @@ if test "x$with_java" != "xno"; then
         else
             JAVAC="$JAVA/bin/javac"
         fi
-        if test ! -x "$JAVA/bin/javah"; then
-            AC_MSG_ERROR([missing $JAVA/bin/javah binary])
-        else
+        if test -x "$JAVA/bin/javah"; then
             JAVAH="$JAVA/bin/javah"
         fi
         if test ! -x "$JAVA/bin/javadoc"; then
@@ -163,6 +161,7 @@ if test "x$with_java" != "xno"; then
     AC_SUBST(JAR_INSTALL_DIR)
     AC_SUBST(JNI_INSTALL_DIR)
     AC_SUBST(JNI_VERSION_INFO)
+    AM_CONDITIONAL([HAVE_JAVAH],[test -n "$JAVAH"])
 fi
 
 AM_CONDITIONAL([HAVE_JAVA],[test "x$with_java" != "xno"
&& test -n "$JAVAC"])
-- 
2.14.3

On Fri, May 04, 2018 at 05:04:42PM +0200, Pino Toscano
wrote:
> Starting OpenJDK 10, the 'javah' utility is no more provided [1],
and
> its functionality is provided by 'javac' itself.  Hence, do not
error
> out on missing 'javah', and store whether it was found; in case it
is
> not, then:
> 1) assume 'javac' has the -h parameter to generate the C header,
and
>    make use of it
> 2) tell the buildsystem that com_redhat_et_libguestfs_GuestFS.h depends
>    on the JAR, since the the header is generated at the step (1)
> 
> [1] https://bugs.java.com/view_bug.do?bug_id=JDK-8182758
> ---
>  java/Makefile.am   | 11 +++++++++++
>  m4/guestfs-java.m4 |  5 ++---
>  2 files changed, 13 insertions(+), 3 deletions(-)
> 
> diff --git a/java/Makefile.am b/java/Makefile.am
> index 376d89d17..81c20f266 100644
> --- a/java/Makefile.am
> +++ b/java/Makefile.am
> @@ -77,6 +77,9 @@ if HAVE_JAVA
>  
>  JAVAC_FLAGS = $(EXTRA_JAVAC_FLAGS) -encoding utf-8
>  JAVADOC_FLAGS = -encoding utf-8
> +if !HAVE_JAVAH
> +JAVAC_FLAGS += -h .
> +endif
>  
>  # Java source.
>  
> @@ -125,10 +128,18 @@ libguestfs_jni_la_LDFLAGS = -version-info
$(JNI_VERSION_INFO) -shared
>  
>  BUILT_SOURCES = com_redhat_et_libguestfs_GuestFS.h
>  
> +if HAVE_JAVAH
> +
>  com_redhat_et_libguestfs_GuestFS.h: $(java_prefix)/GuestFS.class
>  	rm -f $@
>  	$(JAVAH) -classpath $(srcdir):. com.redhat.et.libguestfs.GuestFS
>  
> +else
> +
> +com_redhat_et_libguestfs_GuestFS.h: libguestfs-${VERSION}.jar
> +
> +endif
> +
>  # Documentation.
>  
>  noinst_SCRIPTS = doc-stamp
> diff --git a/m4/guestfs-java.m4 b/m4/guestfs-java.m4
> index 9d0f948b6..2ab932ac4 100644
> --- a/m4/guestfs-java.m4
> +++ b/m4/guestfs-java.m4
> @@ -73,9 +73,7 @@ if test "x$with_java" != "xno"; then
>          else
>              JAVAC="$JAVA/bin/javac"
>          fi
> -        if test ! -x "$JAVA/bin/javah"; then
> -            AC_MSG_ERROR([missing $JAVA/bin/javah binary])
> -        else
> +        if test -x "$JAVA/bin/javah"; then
>              JAVAH="$JAVA/bin/javah"
>          fi
>          if test ! -x "$JAVA/bin/javadoc"; then
> @@ -163,6 +161,7 @@ if test "x$with_java" != "xno";
then
>      AC_SUBST(JAR_INSTALL_DIR)
>      AC_SUBST(JNI_INSTALL_DIR)
>      AC_SUBST(JNI_VERSION_INFO)
> +    AM_CONDITIONAL([HAVE_JAVAH],[test -n "$JAVAH"])
>  fi
>  
>  AM_CONDITIONAL([HAVE_JAVA],[test "x$with_java" !=
"xno" && test -n "$JAVAC"])
> -- 
> 2.14.3
ACK, although perhaps another way to write this would be to have the
configure script define JAVAH as ‘javac -h’.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-p2v converts physical machines to virtual machines.  Boot with a
live CD or over the network (PXE) and turn machines into KVM guests.
http://libguestfs.org/virt-v2v

* Pino Toscano:
> @@ -163,6 +161,7 @@ if test "x$with_java" != "xno";
then
>      AC_SUBST(JAR_INSTALL_DIR)
>      AC_SUBST(JNI_INSTALL_DIR)
>      AC_SUBST(JNI_VERSION_INFO)
> +    AM_CONDITIONAL([HAVE_JAVAH],[test -n "$JAVAH"])
>  fi
>  
>  AM_CONDITIONAL([HAVE_JAVA],[test "x$with_java" !=
"xno" && test -n "$JAVAC"])
The AM_CONDITIONAL must be moved outside the if ... fi shell
conditional, otherwise configure will fail if invoked with
--without-java.

Cheers,
-Hilko

On Sun, May 06, 2018 at 04:11:36PM +0200, Hilko Bengen
wrote:
> * Pino Toscano:
> 
> > @@ -163,6 +161,7 @@ if test "x$with_java" !=
"xno"; then
> >      AC_SUBST(JAR_INSTALL_DIR)
> >      AC_SUBST(JNI_INSTALL_DIR)
> >      AC_SUBST(JNI_VERSION_INFO)
> > +    AM_CONDITIONAL([HAVE_JAVAH],[test -n "$JAVAH"])
> >  fi
> >  
> >  AM_CONDITIONAL([HAVE_JAVA],[test "x$with_java" !=
"xno" && test -n "$JAVAC"])
> 
> The AM_CONDITIONAL must be moved outside the if ... fi shell
> conditional, otherwise configure will fail if invoked with
> --without-java.
Thanks hillu, would you mind just pushing a quick fix?  Probably
easier than going through patch review for an obvious bug and I'm away
for the next week.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
libguestfs lets you edit virtual machines.  Supports shell scripting,
bindings from many languages.  http://libguestfs.org