Fixes for Linux.

`cbinding/refimpl2-config` now puts `libmurefimpl2start.so` on the
"rpath" of the binary.

cbinding/Makefile

@@ -21,13 +21,14 @@ endif
 
 ifeq ($(OS),OSX)
     CFLAGS += -I $(JAVA_HOME)/include/darwin
+    LDFLAGS += -L $(JAVA_HOME)/jre/lib/server -l jvm -rpath $(JAVA_HOME)/jre/lib/server
 endif
 
 ifeq ($(OS),LINUX)
     CFLAGS += -I $(JAVA_HOME)/include/linux
+    LDFLAGS += -L $(JAVA_HOME)/jre/lib/amd64/server -l jvm -Wl,-rpath,$(JAVA_HOME)/jre/lib/amd64/server
 endif
 
-LDFLAGS += -L $(JAVA_HOME)/jre/lib/server -l jvm -rpath $(JAVA_HOME)/jre/lib/server
 
 .PHONY: all
 all: libs tests
@@ -48,7 +49,7 @@ classpath.h: classpath.txt
 tests: test_client
 
 test_client: test_client.c libmurefimpl2start.so
-	$(CC) $(CFLAGS) `./refimpl2-config --istart --cflags --libs` -o $@ $<
+	$(CC) `./refimpl2-config --istart --cflags --libs` -o $@ $<
 
 .PHONY: clean veryclean
 

cbinding/README.md

@@ -11,9 +11,13 @@ compile`. Then come here and type `make JAVA_HOME=/path/to/the/java/home`.
 
 This will produce the `libmurefimpl2start.so` dynamic library that contains code
 that starts the JVM and creates the MuVM instance for your client written in C.
-This library will **hard code the classpath and the JVM path** into the shared
-object, so it only works for this particular `microvm-refimpl2` repository you
-cloned.
+This library will **hard code the classpath and the JVM library path** into the
+shared object, so it only works for this particular `microvm-refimpl2`
+repository you cloned. This is because as this reference implementation is a
+research project, it is unlikely to install it into any well-known places such
+as `/usr`. Hard-coding the JVM's `libjvm.so` path using "rpath" eliminates the
+need to put the JVM library path to `LD_LIBRARY_PATH`, since JVM is seldom
+installed into `/usr/lib`.
 
 ## Usage
 
@@ -36,7 +40,10 @@ function provides more options.
 
 Use the `refimpl2-config` script with the `--istart` flag to indicate your
 program will create the Mu reference implementation instance. Such clients need
-to link against `libmurefimpl2start.so`.
+to link against `libmurefimpl2start.so`, and it will **hard-code its location
+using rpath** for the same reason why it hard-codes the classpath and JVM
+locations, otherwise your executable file will require `libmurefimpl2start.so`
+to be on the `LD_LIBRARY_PATH` to execute.
 
 For example:
 

cbinding/refimpl2-config

@@ -27,7 +27,8 @@ if '--istart' in args:
     if '--cflags' in args:
         print("-I {} ".format(whereami), end="")
     if '--libs' in args:
-        print("-L {} -l murefimpl2start ".format(whereami), end="")
+        print("-L {} -l murefimpl2start -Wl,-rpath,{}".format(
+            whereami, whereami), end="")
 else:
     if '--cflags' in args:
         print("-I {} ".format(whereami), end="")