Issue 4231 - Fix unstable FilterEngineTest.testSetRemoveFilterChangeCallback

libadblockplus-android/jni/JniFileSystem.cpp

+/*
+ * This file is part of Adblock Plus <https://adblockplus.org/>,
+ * Copyright (C) 2006-2016 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/>.
+ */
+
+#include "JniCallbacks.h"
+#include "AdblockPlus/FileSystem.h"
+#include "Utils.h"
+#include <sstream>
+
+static jlong JNICALL JniCtor(JNIEnv* env, jclass clazz, jobject callbackObject)
+{
+  try
+  {
+    return JniPtrToLong(new JniFileSystemCallback(env, callbackObject));
+  }
+  CATCH_THROW_AND_RETURN(env, 0)
+}
+
+static void JNICALL JniDtor(JNIEnv* env, jclass clazz, jlong ptr)
+{
+  delete JniLongToTypePtr<JniFileSystemCallback>(ptr);
+}
+
+JniFileSystemCallback::JniFileSystemCallback(JNIEnv* env, jobject callbackObject)
+  : JniCallbackBase(env, callbackObject),
+  AdblockPlus::FileSystem(),
+  statResultClass(new JniGlobalReference<jclass>(env, env->FindClass(PKG("FileSystem$StatResult"))))
+{
+}
+
+std::shared_ptr<std::istream> JniFileSystemCallback::Read(const std::string& path) const
+{
+  JNIEnvAcquire env(GetJavaVM());
+
+  jmethodID method = env->GetMethodID(
+    *JniLocalReference<jclass>(*env, env->GetObjectClass(GetCallbackObject())),
+    "read",
+    "(Ljava/lang/String;)Ljava/lang/String;");
+
+  JniLocalReference<jstring> jPath(*env, env->NewStringUTF(path.c_str()));
+  jstring jData = (jstring)env->CallObjectMethod(GetCallbackObject(), method, *jPath);
+  CheckAndLogJavaException(*env);
+
+  if (!jData)
+    return NULL;
+
+  std::string cData = JniJavaToStdString(*env, jData);

[anton, 2016/07/10 10:53:11]

some concern here - since it's extremely difficult (is it possible at all?) to
transfer stream over jni (map std::istream to java streams) we're returning
string in java, create std stream for it and return it in c++ side

+  std::shared_ptr<std::istream> cSharedStream(new std::istringstream(cData));
+  return cSharedStream;
+}
+
+void JniFileSystemCallback::Write(const std::string& path, std::shared_ptr<std::istream> data)
+{
+  JNIEnvAcquire env(GetJavaVM());
+
+  jmethodID method = env->GetMethodID(
+    *JniLocalReference<jclass>(*env, env->GetObjectClass(GetCallbackObject())),
+    "write",
+    "(Ljava/lang/String;Ljava/lang/String;)V");
+
+  JniLocalReference<jstring> jPath(*env, env->NewStringUTF(path.c_str()));
+
+  // read all the data from the stream into buffer (no appropriate way to pass streams over JNI)
+  std::string cData = JniStdStreamToStdString(data.get());

[anton, 2016/07/10 10:53:11]

some concern here too - since it's extremely difficult (is it possible at all?)
to transfer stream over jni (map std::istream to java streams) we're reading all
the buffer from c++ stream into std::string and pass java string to java.

+  JniLocalReference<jstring> jData(*env, env->NewStringUTF(cData.c_str()));
+
+  env->CallVoidMethod(GetCallbackObject(), method, *jPath, *jData);
+  CheckAndLogJavaException(*env);
+}
+
+void JniFileSystemCallback::Move(const std::string& fromPath, const std::string& toPath)
+{
+  JNIEnvAcquire env(GetJavaVM());
+
+  jmethodID method = env->GetMethodID(
+    *JniLocalReference<jclass>(*env, env->GetObjectClass(GetCallbackObject())),
+    "move",
+    "(Ljava/lang/String;Ljava/lang/String;)V");
+
+  JniLocalReference<jstring> jFromPath(*env, env->NewStringUTF(fromPath.c_str()));
+  JniLocalReference<jstring> jToPath(*env, env->NewStringUTF(toPath.c_str()));
+
+  env->CallVoidMethod(GetCallbackObject(), method, *jFromPath, *jToPath);
+  CheckAndLogJavaException(*env);
+}
+
+void JniFileSystemCallback::Remove(const std::string& path)
+{
+  JNIEnvAcquire env(GetJavaVM());
+
+  jmethodID method = env->GetMethodID(
+    *JniLocalReference<jclass>(*env, env->GetObjectClass(GetCallbackObject())),
+    "move",
+    "(Ljava/lang/String;Ljava/lang/String;)V");
+
+  JniLocalReference<jstring> jPath(*env, env->NewStringUTF(path.c_str()));
+
+  env->CallVoidMethod(GetCallbackObject(), method, *jPath);
+  CheckAndLogJavaException(*env);
+}
+
+AdblockPlus::FileSystem::StatResult JniFileSystemCallback::Stat(const std::string& path) const
+{
+  JNIEnvAcquire env(GetJavaVM());
+
+  jmethodID method = env->GetMethodID(
+    *JniLocalReference<jclass>(*env, env->GetObjectClass(GetCallbackObject())),
+    "stat",
+    "(Ljava/lang/String;)" TYP("FileSystem$StatResult"));
+
+  JniLocalReference<jstring> jPath(*env, env->NewStringUTF(path.c_str()));
+
+  jobject jStatResult = env->CallObjectMethod(GetCallbackObject(), method, *jPath);
+  CheckAndLogJavaException(*env);
+
+  AdblockPlus::FileSystem::StatResult statResult;
+  method = env->GetMethodID(
+     *JniLocalReference<jclass>(*env, env->GetObjectClass(jStatResult)),
+     "exists",
+     "()Z");
+  statResult.exists = env->CallBooleanMethod(jStatResult, method) ? JNI_TRUE : JNI_FALSE;
+
+  method = env->GetMethodID(
+     *JniLocalReference<jclass>(*env, env->GetObjectClass(jStatResult)),
+     "isDirectory",
+     "()Z");
+  statResult.isDirectory = env->CallBooleanMethod(jStatResult, method) ? JNI_TRUE : JNI_FALSE;
+
+  method = env->GetMethodID(
+     *JniLocalReference<jclass>(*env, env->GetObjectClass(jStatResult)),
+     "isFile",
+     "()Z");
+  statResult.isFile = env->CallBooleanMethod(jStatResult, method) ? JNI_TRUE : JNI_FALSE;
+
+  method = env->GetMethodID(
+     *JniLocalReference<jclass>(*env, env->GetObjectClass(jStatResult)),
+     "getLastModified",
+     "()J");
+  statResult.lastModified = env->CallLongMethod(jStatResult, method);
+
+  return statResult;
+}
+
+std::string JniFileSystemCallback::Resolve(const std::string& path) const
+{
+  JNIEnvAcquire env(GetJavaVM());
+
+  jmethodID method = env->GetMethodID(
+    *JniLocalReference<jclass>(*env, env->GetObjectClass(GetCallbackObject())),
+    "resolve",
+    "(Ljava/lang/String;)Ljava/lang/String;");
+
+  JniLocalReference<jstring> jPath(*env, env->NewStringUTF(path.c_str()));
+
+  jstring jRet = (jstring)env->CallObjectMethod(GetCallbackObject(), method, *jPath);
+  CheckAndLogJavaException(*env);
+
+  return JniJavaToStdString(*env, jRet);
+}
+
+static JNINativeMethod methods[] =
+{
+  { (char*)"ctor", (char*)"(Ljava/lang/Object;)J", (void*)JniCtor },
+  { (char*)"dtor", (char*)"(J)V", (void*)JniDtor }
+};
+
+extern "C" JNIEXPORT void JNICALL Java_org_adblockplus_libadblockplus_FileSystem_registerNatives(JNIEnv *env, jclass clazz)
+{
+  env->RegisterNatives(clazz, methods, sizeof(methods) / sizeof(methods[0]));
+}