/* * 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. */ #ifndef SCOPEDUTFCHARS_H_ #define SCOPEDUTFCHARS_H_ #include <string.h> #include <conscrypt/jniutil.h> // A smart pointer that provides read-only access to a Java string's UTF chars. // Unlike GetStringUTFChars, we throw NullPointerException rather than abort if // passed a null jstring, and c_str will return nullptr. // This makes the correct idiom very simple: // // ScopedUtfChars name(env, java_name); // if (name.c_str() == nullptr) { // return nullptr; // } class ScopedUtfChars { public: ScopedUtfChars(JNIEnv* env, jstring s) : env_(env), string_(s) { if (s == nullptr) { utf_chars_ = nullptr; conscrypt::jniutil::throwNullPointerException(env, nullptr); } else { utf_chars_ = env->GetStringUTFChars(s, nullptr); } } ~ScopedUtfChars() { if (utf_chars_) { env_->ReleaseStringUTFChars(string_, utf_chars_); } } const char* c_str() const { return utf_chars_; } size_t size() const { return strlen(utf_chars_); } const char& operator[](size_t n) const { return utf_chars_[n]; } private: JNIEnv* env_; jstring string_; const char* utf_chars_; // Disallow copy and assignment. ScopedUtfChars(const ScopedUtfChars&); void operator=(const ScopedUtfChars&); }; #endif // SCOPEDUTFCHARS_H_