From 46adf653a1d01b8e87baa30cc9b92616eee1a788 Mon Sep 17 00:00:00 2001
From: Alexandre Montplaisir <alexandre.montplaisir@polymtl.ca>
Date: Thu, 5 Apr 2012 17:15:57 -0400
Subject: [PATCH] Fix: Make the JNI interface actually work

Now a user can import LTTngUst.java (which is now in a proper
package) and then define tracepoints in his application with:

LTTngUst.tracepointString(name, args);

We could eventually ship it in a .jar when the JNI interface is
enabled. It's still very basic, only string payloads are
implemented, and there is no mechanism to enable/disable trace
points call sites at runtime (they are always enabled). The event under
which these events appear is "lttng_ust_java:string".

Signed-off-by: Alexandre Montplaisir <alexandre.montplaisir@polymtl.ca>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---
 liblttng-ust-java/.gitignore                    |  4 ++--
 liblttng-ust-java/{LTTNG_UST.c => LTTngUst.c}   |  5 ++++-
 .../{LTTNG_UST.java => LTTngUst.java}           |  6 ++++--
 liblttng-ust-java/Makefile.am                   | 17 +++++++++--------
 4 files changed, 19 insertions(+), 13 deletions(-)
 rename liblttng-ust-java/{LTTNG_UST.c => LTTngUst.c} (85%)
 rename liblttng-ust-java/{LTTNG_UST.java => LTTngUst.java} (88%)

diff --git a/liblttng-ust-java/.gitignore b/liblttng-ust-java/.gitignore
index ab97d041..677373ea 100644
--- a/liblttng-ust-java/.gitignore
+++ b/liblttng-ust-java/.gitignore
@@ -1,2 +1,2 @@
-UST.class
-UST.h
+org_lttng_ust_LTTngUst.h
+org/
diff --git a/liblttng-ust-java/LTTNG_UST.c b/liblttng-ust-java/LTTngUst.c
similarity index 85%
rename from liblttng-ust-java/LTTNG_UST.c
rename to liblttng-ust-java/LTTngUst.c
index af29c1e9..3d23d6a1 100644
--- a/liblttng-ust-java/LTTNG_UST.c
+++ b/liblttng-ust-java/LTTngUst.c
@@ -22,7 +22,7 @@
 #define TRACEPOINT_CREATE_PROBES
 #include "lttng_ust_java.h"
 
-JNIEXPORT void JNICALL Java_LTTNG_UST_ust_1java_1event (JNIEnv *env,
+JNIEXPORT void JNICALL Java_org_lttng_ust_LTTngUst_tracepointString(JNIEnv *env,
 						jobject jobj,
 						jstring ev_name,
 						jstring args)
@@ -33,4 +33,7 @@ JNIEXPORT void JNICALL Java_LTTNG_UST_ust_1java_1event (JNIEnv *env,
 	const char *args_cstr = (*env)->GetStringUTFChars(env, args, &iscopy);
 
 	tracepoint(lttng_ust_java, string, ev_name_cstr, args_cstr);
+
+	(*env)->ReleaseStringUTFChars(env, ev_name, ev_name_cstr);
+	(*env)->ReleaseStringUTFChars(env, args, args_cstr);
 }
diff --git a/liblttng-ust-java/LTTNG_UST.java b/liblttng-ust-java/LTTngUst.java
similarity index 88%
rename from liblttng-ust-java/LTTNG_UST.java
rename to liblttng-ust-java/LTTngUst.java
index 7ec61103..d3f1edaf 100644
--- a/liblttng-ust-java/LTTNG_UST.java
+++ b/liblttng-ust-java/LTTngUst.java
@@ -16,8 +16,10 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-class LTTNG_UST {
-	public static native void lttng_ust_java_string(String name, String arg);
+package org.lttng.ust;
+
+class LTTngUst {
+	public static native void tracepointString(String name, String arg);
 	static {
 		System.loadLibrary("lttng-ust-java");
 	}
diff --git a/liblttng-ust-java/Makefile.am b/liblttng-ust-java/Makefile.am
index 31915d0d..9e01e045 100644
--- a/liblttng-ust-java/Makefile.am
+++ b/liblttng-ust-java/Makefile.am
@@ -3,19 +3,20 @@ if BUILD_JNI_INTERFACE
 AM_CPPFLAGS = -I$(top_srcdir)/include
 
 lib_LTLIBRARIES = liblttng-ust-java.la
-liblttng_ust_java_la_SOURCES = LTTNG_UST.c LTTNG_UST.h lttng_ust_java.h
-dist_noinst_DATA = LTTNG_UST.java
+liblttng_ust_java_la_SOURCES = LTTngUst.c org_lttng_ust_LTTngUst.h lttng_ust_java.h
+dist_noinst_DATA = LTTngUst.java
 liblttng_ust_java_la_LIBADD = -lc -L$(top_builddir)/liblttng-ust/.libs -llttng-ust
 
-all: LTTNG_UST.class LTTNG_UST.h
+all: LTTngUst.class org_lttng_ust_LTTngUst.h
 
 clean-local:
-	rm -rf LTTNG_UST.h LTTNG_UST.class
+	rm  org_lttng_ust_LTTngUst.h
+	rm -rf org/
 
-LTTNG_UST.class: LTTNG_UST.java
-	javac -d "$(builddir)" "$(srcdir)/LTTNG_UST.java"
+LTTngUst.class: LTTngUst.java
+	javac -d "$(builddir)" "$(srcdir)/LTTngUst.java"
 
-LTTNG_UST.h: LTTNG_UST.class
-	javah -classpath ./ -jni LTTNG_UST
+org_lttng_ust_LTTngUst.h: LTTngUst.class
+	javah org.lttng.ust.LTTngUst
 
 endif
-- 
2.34.1