MTP: Add MtpServer Java class to wrap MTP device support.

Change-Id: I818c2d3b3f52ad5bb515acc4d3288b2b43e11908
Signed-off-by: Mike Lockwood <lockwood@android.com>
diff --git a/core/jni/android_media_MtpServer.cpp b/core/jni/android_media_MtpServer.cpp
new file mode 100644
index 0000000..9f961a2
--- /dev/null
+++ b/core/jni/android_media_MtpServer.cpp
@@ -0,0 +1,162 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "MtpServerJNI"
+#include "utils/Log.h"
+
+#include <stdio.h>
+#include <assert.h>
+#include <limits.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <utils/threads.h>
+
+#include "jni.h"
+#include "JNIHelp.h"
+#include "android_runtime/AndroidRuntime.h"
+
+#include "MtpServer.h"
+
+namespace android {
+
+// ----------------------------------------------------------------------------
+
+static jfieldID field_context;
+
+
+// ----------------------------------------------------------------------------
+
+static bool ExceptionCheck(void* env)
+{
+    return ((JNIEnv *)env)->ExceptionCheck();
+}
+
+class MtpThread : public Thread {
+private:
+    String8 mStoragePath;
+    String8 mDatabasePath;
+    bool mDone;
+    bool mScannedOnce;
+
+public:
+    MtpThread(const char* storagePath, const char* databasePath)
+        : mStoragePath(storagePath), mDatabasePath(databasePath), mDone(false), mScannedOnce(false)
+    {
+    }
+
+    virtual bool threadLoop() {
+        int fd = open("/dev/mtp_usb", O_RDWR);
+        printf("open returned %d\n", fd);
+        if (fd < 0) {
+            LOGE("could not open MTP driver\n");
+            return false;
+        }
+
+        MtpServer* server = new MtpServer(fd, mDatabasePath);
+        server->addStorage(mStoragePath);
+
+        // temporary
+        LOGD("MtpThread server->scanStorage");
+        server->scanStorage();
+        LOGD("MtpThread server->run");
+        server->run();
+        close(fd);
+        delete server;
+
+        bool done = mDone;
+        if (done)
+            delete this;
+        LOGD("threadLoop returning %s", (done ? "false" : "true"));
+        return !done;
+    }
+
+    void setDone() { mDone = true; }
+};
+
+static void
+android_media_MtpServer_setup(JNIEnv *env, jobject thiz, jstring storagePath, jstring databasePath)
+{
+    LOGD("setup\n");
+
+    const char *storagePathStr = env->GetStringUTFChars(storagePath, NULL);
+    const char *databasePathStr = env->GetStringUTFChars(databasePath, NULL);
+
+    MtpThread* thread = new MtpThread(storagePathStr, databasePathStr);
+    env->SetIntField(thiz, field_context, (int)thread);
+
+    env->ReleaseStringUTFChars(storagePath, storagePathStr);
+    env->ReleaseStringUTFChars(databasePath, databasePathStr);
+}
+
+static void
+android_media_MtpServer_finalize(JNIEnv *env, jobject thiz)
+{
+    LOGD("finalize\n");
+}
+
+
+static void
+android_media_MtpServer_start(JNIEnv *env, jobject thiz)
+{
+    LOGD("start\n");
+    MtpThread *thread = (MtpThread *)env->GetIntField(thiz, field_context);
+    thread->run("MtpThread");
+}
+
+static void
+android_media_MtpServer_stop(JNIEnv *env, jobject thiz)
+{
+    LOGD("stop\n");
+    MtpThread *thread = (MtpThread *)env->GetIntField(thiz, field_context);
+    if (thread) {
+        thread->setDone();
+        env->SetIntField(thiz, field_context, 0);
+    }
+}
+
+// ----------------------------------------------------------------------------
+
+static JNINativeMethod gMethods[] = {
+    {"native_setup",            "(Ljava/lang/String;Ljava/lang/String;)V",  (void *)android_media_MtpServer_setup},
+    {"native_finalize",         "()V",  (void *)android_media_MtpServer_finalize},
+    {"native_start",            "()V",  (void *)android_media_MtpServer_start},
+    {"native_stop",             "()V",  (void *)android_media_MtpServer_stop},
+};
+
+static const char* const kClassPathName = "android/media/MtpServer";
+
+int register_android_media_MtpServer(JNIEnv *env)
+{
+    jclass clazz;
+
+    LOGD("register_android_media_MtpServer\n");
+
+    clazz = env->FindClass("android/media/MtpServer");
+    if (clazz == NULL) {
+        LOGE("Can't find android/media/MtpServer");
+        return -1;
+    }
+    field_context = env->GetFieldID(clazz, "mNativeContext", "I");
+    if (field_context == NULL) {
+        LOGE("Can't find MtpServer.mNativeContext");
+        return -1;
+    }
+
+    return AndroidRuntime::registerNativeMethods(env,
+                "android/media/MtpServer", gMethods, NELEM(gMethods));
+}
+
+} // namespace android