Java API for mojo system.

mojo/android/system/core_impl.cc

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "mojo/android/system/core_impl.h"
+
+#include "base/android/base_jni_registrar.h"
+#include "base/android/jni_android.h"
+#include "base/android/jni_registrar.h"
+#include "base/android/library_loader/library_loader_hooks.h"
+#include "base/logging.h"
+#include "jni/CoreImpl_jni.h"
+#include "mojo/embedder/embedder.h"
+#include "mojo/public/c/system/core.h"
+
+namespace mojo {
+namespace android {
+
+static void Constructor(JNIEnv* env, jobject jcaller) {
+  mojo::embedder::Init();
+}
+
+static jlong GetTimeTicksNow(JNIEnv* env, jobject jcaller) {
+  return MojoGetTimeTicksNow();
+}
+
+static jint WaitMany(JNIEnv* env,
+                     jobject jcaller,
+                     jobject buffer,
+                     jlong deadline) {
+  // Buffer contains first the list of handles, then the list of flags.
+  const void* buffer_start = env->GetDirectBufferAddress(buffer);
+  DCHECK(buffer_start);
+  const size_t record_size = 8;
+  const size_t buffer_size = env->GetDirectBufferCapacity(buffer);
+  DCHECK_EQ(buffer_size % record_size, 0u);
+
+  const size_t nb_handles = buffer_size / record_size;
+  const MojoHandle* handle_start = static_cast<const MojoHandle*>(buffer_start);
+  const MojoWaitFlags* flags_start =
+      static_cast<const MojoWaitFlags*>(handle_start + nb_handles);
+  return MojoWaitMany(handle_start, flags_start, nb_handles, deadline);
+}
+
+static jobject CreateMessagePipe(JNIEnv* env, jobject jcaller) {
+  MojoHandle handle1;
+  MojoHandle handle2;
+  MojoResult result = MojoCreateMessagePipe(&handle1, &handle2);
+  return Java_CoreImpl_newNativeCreationResult(env, result, handle1, handle2)
+      .Release();
+}
+
+static jobject CreateDataPipe(JNIEnv* env,
+                              jobject jcaller,
+                              jobject options_buffer) {
+  const MojoCreateDataPipeOptions* options = NULL;
+  if (options_buffer) {
+    const void* buffer_start = env->GetDirectBufferAddress(options_buffer);
+    DCHECK(buffer_start);
+    const size_t buffer_size = env->GetDirectBufferCapacity(options_buffer);
+    DCHECK_EQ(buffer_size, sizeof(MojoCreateDataPipeOptions));
+    options = static_cast<const MojoCreateDataPipeOptions*>(buffer_start);
+    DCHECK_EQ(options->struct_size, buffer_size);
+  }
+  MojoHandle handle1;
+  MojoHandle handle2;
+  MojoResult result = MojoCreateDataPipe(options, &handle1, &handle2);
+  return Java_CoreImpl_newNativeCreationResult(env, result, handle1, handle2)
+      .Release();
+}
+
+static jobject CreateSharedBuffer(JNIEnv* env,
+                                  jobject jcaller,
+                                  jobject options_buffer,
+                                  jlong num_bytes) {
+  const MojoCreateSharedBufferOptions* options = 0;
+  if (options_buffer) {
+    const void* buffer_start = env->GetDirectBufferAddress(options_buffer);
+    DCHECK(buffer_start);
+    const size_t buffer_size = env->GetDirectBufferCapacity(options_buffer);
+    DCHECK_EQ(buffer_size, sizeof(MojoCreateSharedBufferOptions));
+    options = static_cast<const MojoCreateSharedBufferOptions*>(buffer_start);
+    DCHECK_EQ(options->struct_size, buffer_size);
+  }
+  MojoHandle handle;
+  MojoResult result = MojoCreateSharedBuffer(options, num_bytes, &handle);
+  return Java_CoreImpl_newNativeCreationResult(env, result, handle, 0)
+      .Release();
+}
+
+static jint Close(JNIEnv* env, jobject jcaller, jint mojo_handle) {
+  return MojoClose(mojo_handle);
+}
+
+static jint Wait(JNIEnv* env,
+                 jobject jcaller,
+                 jint mojo_handle,
+                 jint flags,
+                 jlong deadline) {
+  return MojoWait(mojo_handle, flags, deadline);
+}
+
+static jint WriteMessage(JNIEnv* env,
+                         jobject jcaller,
+                         jint mojo_handle,
+                         jobject bytes,
+                         jint num_bytes,
+                         jobject handles_buffer,
+                         jint flags) {
+  const void* buffer_start = 0;
+  uint32_t buffer_size = 0;
+  if (bytes) {
+    buffer_start = env->GetDirectBufferAddress(bytes);
+    DCHECK(buffer_start);
+    DCHECK(env->GetDirectBufferCapacity(bytes) >= num_bytes);
+    buffer_size = num_bytes;
+  }
+  const MojoHandle* handles = 0;
+  uint32_t num_handles = 0;
+  if (handles_buffer) {
+    handles =
+        static_cast<MojoHandle*>(env->GetDirectBufferAddress(handles_buffer));
+    num_handles = env->GetDirectBufferCapacity(handles_buffer) / 4;
+  }
+  // Java code will handle invalidating handles if the write succeeded.
+  return MojoWriteMessage(
+      mojo_handle, buffer_start, buffer_size, handles, num_handles, flags);
+}
+
+static jobject ReadMessage(JNIEnv* env,
+                           jobject jcaller,
+                           jint mojo_handle,
+                           jobject bytes,
+                           jobject handles_buffer,
+                           jint flags) {
+  void* buffer_start = 0;
+  uint32_t buffer_size = 0;
+  if (bytes) {
+    buffer_start = env->GetDirectBufferAddress(bytes);
+    DCHECK(buffer_start);
+    buffer_size = env->GetDirectBufferCapacity(bytes);
+  }
+  MojoHandle* handles = 0;
+  uint32_t num_handles = 0;
+  if (handles_buffer) {
+    handles =
+        static_cast<MojoHandle*>(env->GetDirectBufferAddress(handles_buffer));
+    num_handles = env->GetDirectBufferCapacity(handles_buffer) / 4;
+  }
+  MojoResult result = MojoReadMessage(
+      mojo_handle, buffer_start, &buffer_size, handles, &num_handles, flags);
+  // Jave code will handle taking ownership of any received handle.
+  return Java_CoreImpl_newNativeReadMessageResult(
+             env, result, buffer_size, num_handles).Release();
+}
+
+static jint ReadData(JNIEnv* env,
+                     jobject jcaller,
+                     jint mojo_handle,
+                     jobject elements,
+                     jint elements_capacity,
+                     jint flags) {
+  void* buffer_start = 0;
+  uint32_t buffer_size = elements_capacity;
+  if (elements) {
+    buffer_start = env->GetDirectBufferAddress(elements);
+    DCHECK(buffer_start);
+    DCHECK(elements_capacity <= env->GetDirectBufferCapacity(elements));
+  }
+  MojoResult result =
+      MojoReadData(mojo_handle, buffer_start, &buffer_size, flags);
+  if (result < 0) {
+    return result;
+  }
+  return buffer_size;
+}
+
+static jobject BeginReadData(JNIEnv* env,
+                             jobject jcaller,
+                             jint mojo_handle,
+                             jint num_bytes,
+                             jint flags) {
+  void const* buffer = 0;
+  uint32_t buffer_size = num_bytes;
+  MojoResult result =
+      MojoBeginReadData(mojo_handle, &buffer, &buffer_size, flags);
+  jobject byte_buffer = 0;
+  if (result == MOJO_RESULT_OK) {
+    byte_buffer =
+        env->NewDirectByteBuffer(const_cast<void*>(buffer), buffer_size);
+  }
+  return Java_CoreImpl_newNativeCodeAndBufferResult(env, result, byte_buffer)
+      .Release();
+}
+
+static jint EndReadData(JNIEnv* env,
+                        jobject jcaller,
+                        jint mojo_handle,
+                        jint num_bytes_read) {
+  return MojoEndReadData(mojo_handle, num_bytes_read);
+}
+
+static jint WriteData(JNIEnv* env,
+                      jobject jcaller,
+                      jint mojo_handle,
+                      jobject elements,
+                      jint limit,
+                      jint flags) {
+  void* buffer_start = env->GetDirectBufferAddress(elements);
+  DCHECK(buffer_start);
+  DCHECK(limit <= env->GetDirectBufferCapacity(elements));
+  uint32_t buffer_size = limit;
+  MojoResult result =
+      MojoWriteData(mojo_handle, buffer_start, &buffer_size, flags);
+  if (result < 0) {
+    return result;
+  }
+  return buffer_size;
+}
+
+static jobject BeginWriteData(JNIEnv* env,
+                              jobject jcaller,
+                              jint mojo_handle,
+                              jint num_bytes,
+                              jint flags) {
+  void* buffer = 0;
+  uint32_t buffer_size = num_bytes;
+  MojoResult result =
+      MojoBeginWriteData(mojo_handle, &buffer, &buffer_size, flags);
+  jobject byte_buffer = 0;
+  if (result == MOJO_RESULT_OK) {
+    byte_buffer = env->NewDirectByteBuffer(buffer, buffer_size);
+  }
+  return Java_CoreImpl_newNativeCodeAndBufferResult(env, result, byte_buffer)
+      .Release();
+}
+
+static jint EndWriteData(JNIEnv* env,
+                         jobject jcaller,
+                         jint mojo_handle,
+                         jint num_bytes_written) {
+  return MojoEndWriteData(mojo_handle, num_bytes_written);
+}
+
+static jobject Duplicate(JNIEnv* env,
+                         jobject jcaller,
+                         jint mojo_handle,
+                         jobject options_buffer) {
+  const MojoDuplicateBufferHandleOptions* options = 0;
+  if (options_buffer) {
+    const void* buffer_start = env->GetDirectBufferAddress(options_buffer);
+    DCHECK(buffer_start);
+    const size_t buffer_size = env->GetDirectBufferCapacity(options_buffer);
+    DCHECK_EQ(buffer_size, sizeof(MojoDuplicateBufferHandleOptions));
+    options =
+        static_cast<const MojoDuplicateBufferHandleOptions*>(buffer_start);
+    DCHECK_EQ(options->struct_size, buffer_size);
+  }
+  MojoHandle handle;
+  MojoResult result = MojoDuplicateBufferHandle(mojo_handle, options, &handle);
+  return Java_CoreImpl_newNativeCreationResult(env, result, handle, 0)
+      .Release();
+}
+
+static jobject Map(JNIEnv* env,
+                   jobject jcaller,
+                   jint mojo_handle,
+                   jlong offset,
+                   jlong num_bytes,
+                   jint flags) {
+  void* buffer = 0;
+  MojoResult result =
+      MojoMapBuffer(mojo_handle, offset, num_bytes, &buffer, flags);
+  jobject byte_buffer = 0;
+  if (result == MOJO_RESULT_OK) {
+    byte_buffer = env->NewDirectByteBuffer(buffer, num_bytes);
+  }
+  return Java_CoreImpl_newNativeCodeAndBufferResult(env, result, byte_buffer)
+      .Release();
+}
+
+static int Unmap(JNIEnv* env, jobject jcaller, jobject buffer) {
+  void* buffer_start = env->GetDirectBufferAddress(buffer);
+  DCHECK(buffer_start);
+  return MojoUnmapBuffer(buffer_start);
+}
+
+bool RegisterCoreImpl(JNIEnv* env) {
+  return RegisterNativesImpl(env);
+}
+
+}  // namespace android
+}  // namespace mojo