New JNI bindings

jni/Utils.h

 /*
  * This file is part of Adblock Plus <http://adblockplus.org/>,
  * Copyright (C) 2006-2013 Eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 #ifndef UTILS_H
 #define UTILS_H
 
 #include <string>
 #include <algorithm>
 #include <jni.h>
+#include <stdexcept>
+
+#include <AdblockPlus.h>
+#include <AdblockPlus/tr1_memory.h>
+
+#include "v8/v8stdint.h"
+
+#define PKG(x) "org/adblockplus/android/api/" x
+#define TYP(x) "L" PKG(x) ";"
+
+#define ABP_JNI_VERSION JNI_VERSION_1_6
+
+namespace AdblockPlus
+{
+namespace Android
+{
+
+void JniThrowException(JNIEnv* env, const std::string& message);
+
+void JniThrowException(JNIEnv* env, const std::exception& e);
+
+void JniThrowException(JNIEnv* env);
+
+class JNIEnvAcquire
+{
+public:
+  JNIEnvAcquire(JavaVM* javaVM) :
+      m_JavaVM(javaVM), m_JNIEnv(0), m_AttachStatus(0)
+  {
+    m_AttachStatus = javaVM->GetEnv((void **)&m_JNIEnv, ABP_JNI_VERSION);
+    if (m_AttachStatus == JNI_EDETACHED)
+    {
+      if (javaVM->AttachCurrentThread(&m_JNIEnv, 0))
+      {
+        // This one is FATAL, we can't recover from this (because without a JVM we're dead), so
+        // throwing a runtime_exception in a ctor can be tolerated here IMHO
+        throw std::runtime_error("Failed to get JNI environment");
+      }
+    }
+  }
+
+  ~JNIEnvAcquire()
+  {
+    if (m_AttachStatus == JNI_EDETACHED)
+    {
+      m_JavaVM->DetachCurrentThread();
+    }
+  }
+
+  inline JNIEnv* operator*()
+  {
+    return m_JNIEnv;
+  }
+
+  inline JNIEnv* operator->()
+  {
+    return m_JNIEnv;
+  }
+
+private:
+  JavaVM* m_JavaVM;
+  JNIEnv* m_JNIEnv;
+  int m_AttachStatus;
+};
+
+template<typename T>
+class JniGlobalReference
+{
+public:
+  JniGlobalReference(JNIEnv* env, T reference)
+  {
+    env->GetJavaVM(&m_JavaVM);
+    m_Reference = static_cast<T>(env->NewGlobalRef(static_cast<jobject>(reference)));
+  }
+
+  ~JniGlobalReference()
+  {
+    JNIEnvAcquire env(m_JavaVM);
+
+    env->DeleteGlobalRef(static_cast<jobject>(m_Reference));
+  }
+
+  JniGlobalReference(const JniGlobalReference& other);
+  JniGlobalReference& operator=(const JniGlobalReference& other);
+
+  inline T get()
+  {
+    return m_Reference;
+  }
+
+  typedef std::tr1::shared_ptr<JniGlobalReference<T> > PTR;
+
+private:
+  T m_Reference;
+  JavaVM* m_JavaVM;
+};
+
+inline void* JniLong2Ptr(jlong value)
+{
+  return reinterpret_cast<void*>((size_t)value);
+}
+
+inline jlong JniPtr2Long(void* ptr)
+{
+  return (jlong)reinterpret_cast<size_t>(ptr);
+}
+
+// TODO(rje): It's feeling a bit dirty casting to shared_ptr<T: JsValue> directly, so maybe
+// implement a special cast functions that first reinterpret_casts to shared_ptr<JsValue> and then
+// dynamic_casts to shared_ptr<T: JsValue> ... also as the same inheritance is mirrored on the Java
+// side (and Java will throw a class cast exception on error) this shouldn't be an issue (TM)
+template<typename T>
+inline T* JniLong2TypePtr(jlong value)
+{
+  return reinterpret_cast<T*>((size_t)value);
+}
+
+jobject NewJniArrayList(JNIEnv* env);
+
+std::string JniJava2StdString(JNIEnv* env, jstring str);
+
+void JniAddObjectToList(JNIEnv* env, jobject list, jobject value);
+
+inline std::string JniGetStringField(JNIEnv* env, jclass clazz, jobject jObj, const char* name)
+{
+  return AdblockPlus::Android::JniJava2StdString(env,
+      reinterpret_cast<jstring>(env->GetObjectField(jObj, env->GetFieldID(clazz, name, "Ljava/lang/String;"))));
+}
+
+inline bool JniGetBooleanField(JNIEnv* env, jclass clazz, jobject jObj, const char* name)
+{
+  return env->GetBooleanField(jObj, env->GetFieldID(clazz, name, "Z")) == JNI_TRUE;
+}
+
+inline int32_t JniGetIntField(JNIEnv* env, jclass clazz, jobject jObj, const char* name)
+{
+  return (int32_t)env->GetBooleanField(jObj, env->GetFieldID(clazz, name, "I"));
+}
+
+inline int64_t JniGetLongField(JNIEnv* env, jclass clazz, jobject jObj, const char* name)
+{
+  return (int64_t)env->GetBooleanField(jObj, env->GetFieldID(clazz, name, "J"));
+}
+
+inline jobject NewJniFilter(JNIEnv* env, const AdblockPlus::FilterPtr& filter)
+{
+  jclass clazz = env->FindClass(PKG("Filter"));
+  jmethodID method = env->GetMethodID(clazz, "<init>", "(J)V");
+  return env->NewObject(clazz, method, JniPtr2Long(new AdblockPlus::FilterPtr(filter)));
+}
+
+inline jobject NewJniSubscription(JNIEnv* env, const AdblockPlus::SubscriptionPtr& subscription)
+{
+  jclass clazz = env->FindClass(PKG("Subscription"));
+  jmethodID method = env->GetMethodID(clazz, "<init>", "(J)V");
+  return env->NewObject(clazz, method, JniPtr2Long(new AdblockPlus::SubscriptionPtr(subscription)));
+}
+
+} // namespace Android
+} // namespace AdblockPlus
+
+#define TRY try
+
+#define CATCH_AND_THROW(jEnv) \
+  catch (const std::exception& except) \
+  { \
+    AdblockPlus::Android::JniThrowException(jEnv, except); \
+  } \
+  catch (...) \
+  { \
+    AdblockPlus::Android::JniThrowException(jEnv); \
+  }
+
+#define CATCH_THROW_AND_RETURN(jEnv, retVal) \
+  catch (const std::exception& except) \
+  { \
+    AdblockPlus::Android::JniThrowException(jEnv, except); \
+    return retVal; \
+  } \
+  catch (...) \
+  { \
+    AdblockPlus::Android::JniThrowException(jEnv); \
+    return retVal; \
+  }
 
 const std::string GetString(JNIEnv *pEnv, jstring str);
 
 template<class T>
 T TrimString(T text)
 {
   // Via http://stackoverflow.com/questions/216823/whats-the-best-way-to-trim-stdstring
   T trimmed(text);
   trimmed.erase(trimmed.begin(), std::find_if(trimmed.begin(), trimmed.end(), std::not1(std::ptr_fun<int, int>(std::isspace))));
   trimmed.erase(std::find_if(trimmed.rbegin(), trimmed.rend(), std::not1(std::ptr_fun<int, int>(std::isspace))).base(), trimmed.end());
   return trimmed;
 }
 
 #endif