/* -*- Mode: c++; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*- * This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ #include <jni.h> #include <string.h> #include <sys/mman.h> extern "C" { JNIEXPORT void JNICALL Java_org_mozilla_gecko_mozglue_SharedMemBuffer_nativeReadFromDirectBuffer(JNIEnv* jenv, jclass, jobject src, jlong dest, jint offset, jint size) { uint8_t* from = static_cast<uint8_t*>(jenv->GetDirectBufferAddress(src)); if (from == nullptr) { jenv->ThrowNew(jenv->FindClass("java/lang/NullPointerException"), "Null direct buffer"); return; } void* to = reinterpret_cast<void*>(dest); if (to == nullptr) { jenv->ThrowNew(jenv->FindClass("java/lang/NullPointerException"), "Null shared memory buffer"); return; } memcpy(to, from + offset, size); } JNIEXPORT void JNICALL Java_org_mozilla_gecko_mozglue_SharedMemBuffer_nativeWriteToDirectBuffer(JNIEnv* jenv, jclass, jlong src, jobject dest, jint offset, jint size) { uint8_t* from = reinterpret_cast<uint8_t*>(src); if (from == nullptr) { jenv->ThrowNew(jenv->FindClass("java/lang/NullPointerException"), "Null shared memory buffer"); return; } void* to = jenv->GetDirectBufferAddress(dest); if (to == nullptr) { jenv->ThrowNew(jenv->FindClass("java/lang/NullPointerException"), "Null direct buffer"); return; } memcpy(to, from + offset, size); } JNIEXPORT jlong JNICALL Java_org_mozilla_gecko_mozglue_SharedMemory_map(JNIEnv *env, jobject jobj, jint fd, jint length) { void* address = mmap(NULL, length, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); return jlong(address); } JNIEXPORT void JNICALL Java_org_mozilla_gecko_mozglue_SharedMemory_unmap(JNIEnv *env, jobject jobj, jlong address, jint size) { munmap((void*)address, (size_t)size); } }