1 files changed, 65 insertions, 0 deletions
diff --git a/mozglue/android/SharedMemNatives.cpp b/mozglue/android/SharedMemNatives.cpp
new file mode 100644
index 000000000..d186d6e21
--- /dev/null
+++ b/mozglue/android/SharedMemNatives.cpp
@@ -0,0 +1,65 @@
+/* -*- 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);
+}
+
+}
+\ No newline at end of file