[build] Allow tests to run on Linux (#155)

In order to do so we need to configure everything so that the
native `libjvm` is found by the runtime. This patch adds detection
logic as well as modifies the dllmap to work on Linux in addition
to macOS.

Makefile

@@ -5,9 +5,11 @@ CONFIGURATION = Debug
 
 ifeq ($(OS),Darwin)
 NATIVE_EXT = .dylib
+DLLMAP_OS_NAME = osx
 endif
 ifeq ($(OS),Linux)
 NATIVE_EXT = .so
+DLLMAP_OS_NAME = linux
 endif
 
 XA_CONFIGURATION  = XAIntegrationDebug
@@ -70,7 +72,7 @@ $(PACKAGES) $(NUNIT_CONSOLE):
 
 src/Java.Runtime.Environment/Java.Runtime.Environment.dll.config: src/Java.Runtime.Environment/Java.Runtime.Environment.dll.config.in \
 		bin/Build$(CONFIGURATION)/JdkInfo.props
-	sed 's#@JI_JVM_PATH@#$(JI_JVM_PATH)#g' < $< > $@
+	sed -e 's#@JI_JVM_PATH@#$(JI_JVM_PATH)#g' -e 's#@OS_NAME@#$(DLLMAP_OS_NAME)#g' < $< > $@
 
 xa-fxcop: lib/gendarme-2.10/gendarme.exe bin/$(XA_CONFIGURATION)/Java.Interop.dll
 	$(RUNTIME) $< --html xa-gendarme.html $(if @(GENDARME_XML),--xml xa-gendarme.xml) --ignore gendarme-ignore.txt bin/$(XA_CONFIGURATION)/Java.Interop.dll

build-tools/scripts/jdk.mk

@@ -92,22 +92,39 @@ endif   # Darwin
 ifeq ($(OS),Linux)
 
 # This is for Ubuntu and derivatives (possibly Debian too)
-_DEFAULT_LINUX_JAVA_INCLUDE_DIRS  = /usr/lib/jvm/default-java/include/
+_DEFAULT_LINUX_JAVA_ROOT          = /usr/lib/jvm/default-java
+_DEFAULT_LINUX_JAVA_INCLUDE_DIRS  = $(_DEFAULT_LINUX_JAVA_ROOT)/include/
 _LINUX_JAVA_FALLBACK_DIRS         = /usr/lib/jvm/java*
 _LINUX_JAVA_JNI_INCLUDE_DIR       = include
+_LINUX_JAVA_ROOT                  = $(_DEFAULT_LINUX_JAVA_ROOT)
+_LINUX_JAVA_ARCH_64               = amd64
+_LINUX_JAVA_ARCH_32               = i386
 
 _DESKTOP_JAVA_INCLUDE_DIRS = $(_DEFAULT_LINUX_JAVA_INCLUDE_DIRS)
 
 ifeq ($(wildcard $(_DESKTOP_JAVA_INCLUDE_DIRS)),)
 _DESKTOP_JAVA_INCLUDE_DIRS  = $(wildcard $(JAVA_HOME)/include)
-endif
+_LINUX_JAVA_ROOT            = $(JAVA_HOME)
+endif # No default Java location, $JAVA_HOME check
+
 ifeq ($(wildcard $(_DESKTOP_JAVA_INCLUDE_DIRS)),)
 LATEST_JDK            := $(shell ls -dtr $(_LINUX_JAVA_FALLBACK_DIRS) | sort | tail -1)
 _DESKTOP_JAVA_INCLUDE_DIRS  = $(LATEST_JDK)/$(_LINUX_JAVA_JNI_INCLUDE_DIR)
-endif
+_LINUX_JAVA_ROOT            = $(LATEST_JDK)
+endif # No $JAVA_HOME, find the latest version
 
 JI_JDK_INCLUDE_PATHS = $(_DESKTOP_JAVA_INCLUDE_DIRS) $(_DESKTOP_JAVA_INCLUDE_DIRS)/linux
 
+ifneq ($(wildcard $(_LINUX_JAVA_ROOT)/jre/lib/$(_LINUX_JAVA_ARCH_64)/server/libjvm.so),)
+JI_JVM_PATH                 = $(_LINUX_JAVA_ROOT)/jre/lib/$(_LINUX_JAVA_ARCH_64)/server/libjvm.so
+endif # Find 64-bit libjvm
+
+ifeq ($(JI_JVM_PATH),) # (1) No 64-bit java arch
+ifneq ($(wildcard $(_LINUX_JAVA_ROOT)/jre/lib/$(_LINUX_JAVA_ARCH_32)/server/libjvm.so),) # (2) check 32-bit instead, even on a 64-bit system
+JI_JVM_PATH                 = $(_LINUX_JAVA_ROOT)/jre/lib/$(_LINUX_JAVA_ARCH_32)/server/libjvm.so
+endif # (2)
+endif # (1)
+
 endif   # Linux
 
 $(JI_JVM_PATH):

src/Java.Runtime.Environment/Java.Runtime.Environment.dll.config.in

@@ -1,3 +1,3 @@
 <configuration>
-  <dllmap dll="jvm.dll" os="osx" target="@JI_JVM_PATH@"/>
+  <dllmap dll="jvm.dll" os="@OS_NAME@" target="@JI_JVM_PATH@"/>
 </configuration>