CouchDB in-process changes

* CouchDB now runs in the same process as the Dalvik VM.
* JNI library/NIF added for direct communication from Erlang for:
  - Collation via java.text.Collator
  - Notification of CouchDB start, along with URL
  - Direct logging to logcat (as we no longer capture stdout)
* .beam and .app files are now loaded directly from the .APK
* Extra files layout has changed. .beam, .app, and .so files are now
  in overlay.zip, which is extracted over the target project by the
  couchbase.xml ant script.
* .so files now live in libs/armeabi, and get auto-extracted by android
Change-Id: I8ad5817a285ad831ca572683a35799ceb36c3ada
Reviewed-on: http://review.couchbase.org/9617
Reviewed-by: Aaron Miller <apage43@ninjawhale.com>
Tested-by: Aaron Miller <apage43@ninjawhale.com>

.classpath

@@ -4,5 +4,6 @@
 	<classpathentry kind="src" path="gen"/>
 	<classpathentry kind="con" path="com.android.ide.eclipse.adt.ANDROID_FRAMEWORK"/>
 	<classpathentry kind="lib" path="libs/commons-compress-1.0.jar"/>
+	<classpathentry kind="lib" path="libs/OtpErlang.jar"/>
 	<classpathentry kind="output" path="bin"/>
 </classpath>

build.xml

@@ -95,6 +95,10 @@
 	<target name="dist" depends="couchbase-jar">
 		<zip destfile="bin/Couchbase.zip">
 
+            <fileset dir="${basedir}">
+				<include name="overlay.zip"/>
+            </fileset>
+
 		    <mappedresources>
 		      <fileset dir="${basedir}">
 				<include name="assets/**/*"/>
@@ -124,7 +128,19 @@
 				<include name="README.txt"/>
 			</fileset>
 		</zip>
-	</target>
+    </target>
+
+    <target name="jni">
+        <unzip src="${basedir}/overlay.zip" dest="${basedir}/jni">
+            <patternset>
+                <include name="libs/armeabi/libbeam.so"/>
+            </patternset>
+            <mapper type="flatten"/>
+        </unzip>
+        <exec dir="${basedir}/jni" executable="sh">
+            <arg line="${ndk.dir}/ndk-build"/>
+        </exec>
+    </target>
 
 	<target name="javadoc">
 		 <javadoc

jni/Android.mk

@@ -2,8 +2,8 @@ LOCAL_PATH := $(call my-dir)
 
 include $(CLEAR_VARS)
 
-LOCAL_MODULE    := com_google_ase_Exec
-LOCAL_SRC_FILES := com_google_ase_Exec.cpp
-LOCAL_LDLIBS    := -llog
+LOCAL_MODULE    := com_couchbase_android_ErlangThread
+LOCAL_SRC_FILES := com_couchbase_android_ErlangThread.cpp android_jni_nif.cpp
+LOCAL_LDLIBS    := -llog -ldl -L$(LOCAL_PATH) -lbeam
 
 include $(BUILD_SHARED_LIBRARY)

jni/android_jni_nif.cpp

@@ -0,0 +1,78 @@
+#include "android/log.h"
+#include "erl_nif.h"
+#include <string.h>
+#include <jni.h>
+
+#include "com_couchbase_android_ErlangThread.h"
+
+#define LOG_TAG "JNINIF"
+#define LOGI(...) __android_log_print(ANDROID_LOG_INFO, LOG_TAG, __VA_ARGS__)
+#define LOGV(...) __android_log_print(ANDROID_LOG_VERBOSE, LOG_TAG, __VA_ARGS__)
+#define LOGE(...) __android_log_print(ANDROID_LOG_ERROR, LOG_TAG, __VA_ARGS__)
+
+extern JavaVM *jvm;
+extern jclass ErlangThread;
+extern jmethodID ErlMessageMethod;
+
+struct caller_info {
+    ErlNifPid pid;
+    ErlNifEnv *env;
+};
+
+JNIEXPORT void JNICALL Java_com_couchbase_android_ErlangThread_send_1bin
+  (JNIEnv *env, jclass cls, jbyteArray jbin, jlong cinfo)  {
+    struct caller_info* inf = (struct caller_info*) cinfo;
+    ErlNifEnv* msg = enif_alloc_env();
+    ERL_NIF_TERM bin_term;
+    jsize length = env->GetArrayLength(jbin);
+    jbyte* bindata = (jbyte*) enif_make_new_binary(msg, length, &bin_term);
+    env->GetByteArrayRegion(jbin, 0, length, bindata);
+    enif_send(inf->env, &(inf->pid), msg, bin_term);
+    enif_free_env(msg);
+}
+
+static ERL_NIF_TERM mkatom(ErlNifEnv* env, const char* name) {
+    ERL_NIF_TERM atom;
+    if(enif_make_existing_atom(env, name, &atom, ERL_NIF_LATIN1)) {
+        return atom;
+    } else {
+        return enif_make_atom(env, name);
+    }
+}
+
+static ERL_NIF_TERM jninif_send(ErlNifEnv* nif_env, int argc, const ERL_NIF_TERM argv[])
+{
+    struct caller_info cinf;
+    JNIEnv *env = NULL;
+    char namebuf[512];
+
+    cinf.env = nif_env;
+    enif_self(nif_env, &(cinf.pid));
+
+    if(!enif_get_atom(nif_env, argv[0], namebuf, 512, ERL_NIF_LATIN1)) {
+        return mkatom(nif_env, "name_too_long");
+    }
+
+    jvm->AttachCurrentThread(&env, NULL);
+    if(env == NULL) {
+        return mkatom(nif_env, "jni_error");
+    }
+
+    env->PushLocalFrame(2); //We use 2 local JNI refs per invoc.
+    ErlNifBinary ebin;
+    jbyteArray jbin;
+    jstring name = env->NewStringUTF(namebuf);
+    enif_inspect_binary(nif_env, argv[1], &ebin);
+    jbin = env->NewByteArray(ebin.size);
+    env->SetByteArrayRegion(jbin, 0, ebin.size, (jbyte*) ebin.data);
+    env->CallStaticVoidMethod(ErlangThread, ErlMessageMethod, name, jbin, (jlong) &cinf);
+    env->PopLocalFrame(NULL);
+    return mkatom(nif_env, "ok");
+}
+
+static ErlNifFunc jninif_funcs[] =
+{
+    {"send", 2, jninif_send}
+};
+
+ERL_NIF_INIT(jninif, jninif_funcs, NULL, NULL, NULL, NULL);

jni/com_couchbase_android_ErlangThread.cpp

@@ -0,0 +1,65 @@
+#include "com_couchbase_android_ErlangThread.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <dlfcn.h>
+
+#include "android/log.h"
+
+#define LOG_TAG "ErlangThread"
+#define LOGV(...) __android_log_print(ANDROID_LOG_VERBOSE, LOG_TAG, __VA_ARGS__)
+#define LOGE(...) __android_log_print(ANDROID_LOG_ERROR, LOG_TAG, __VA_ARGS__)
+
+JavaVM *jvm;
+jclass ErlangThread;
+jmethodID ErlMessageMethod;
+
+JNIEXPORT void JNICALL Java_com_couchbase_android_ErlangThread_start_1erlang
+            (JNIEnv *env, jclass cls, jstring j_bindir, jstring j_sopath, jobjectArray j_args) {
+    jboolean iscopy;
+    int i, argc;
+    char ** argv;
+    void (*erl_start)(int, char**) = NULL;
+
+    const char *sopath = env->GetStringUTFChars(j_sopath, &iscopy);
+    const char *bindir = env->GetStringUTFChars(j_bindir, &iscopy);
+
+    void* handle = dlopen(sopath, RTLD_LAZY);
+
+    if(!handle) {
+        LOGE("Failed to open beam .so: %s", dlerror());
+        goto cleanup;
+    }
+    *(void **)(&erl_start) = dlsym(handle, "erl_start");
+    if(!erl_start) {
+        LOGE("Failed to find erl_start: %s", dlerror());
+        goto cleanup;
+    }
+    argc = env->GetArrayLength(j_args);
+    argv = (char**) malloc(sizeof(char*) * argc);
+
+    for(i = 0; i < argc; i++)
+    {
+        argv[i] = (char*) env->GetStringUTFChars((jstring) env->GetObjectArrayElement(j_args, i), &iscopy);
+    }
+    setenv("BINDIR", bindir, 1);
+    env->GetJavaVM(&jvm);
+    ErlMessageMethod = env->GetStaticMethodID(cls, "erl_message", "(Ljava/lang/String;[BJ)V");
+    ErlangThread = (jclass) env->NewGlobalRef(cls);
+    erl_start(argc, argv);
+
+    cleanup:
+    env->DeleteGlobalRef(ErlangThread);
+    env->ReleaseStringUTFChars(j_sopath, sopath);
+    env->ReleaseStringUTFChars(j_bindir, bindir);
+    if(handle) dlclose(handle);
+    if(argv)
+    {
+        for(i = 0; i < argc; i++)
+        {
+            env->ReleaseStringUTFChars((jstring) env->GetObjectArrayElement(j_args, i), argv[i]);
+        }
+        free(argv);
+    }
+    return;
+}