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/* -*- 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);
}
}
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