AudioServer: Port to the new generated IPC mechanism

Fork the IPC Connection classes into Server:: and Client::ConnectionNG.
The new IPC messages are serialized very snugly instead of using the
same generic data structure for all messages.

Remove ASAPI.h since we now generate all of it from AudioServer.ipc :^)

5 files changed, 267 insertions, 265 deletions

diff --git a/Libraries/LibAudio/AClientConnection.cpp b/Libraries/LibAudio/AClientConnection.cpp
index 00f36d6387..3cd78c0aa8 100644
--- a/Libraries/LibAudio/AClientConnection.cpp
+++ b/Libraries/LibAudio/AClientConnection.cpp
@@ -3,23 +3,23 @@
 #include <SharedBuffer.h>
 
 AClientConnection::AClientConnection()
-    : Connection("/tmp/asportal")
+    : ConnectionNG("/tmp/asportal")
 {
 }
 
 void AClientConnection::handshake()
 {
-    auto response = send_sync<ASAPI_Client::Greeting>(getpid());
-    set_server_pid(response.server_pid());
-    set_my_client_id(response.your_client_id());
+    auto response = send_sync<AudioServer::Greet>(getpid());
+    set_server_pid(response->server_pid());
+    set_my_client_id(response->client_id());
 }
 
 void AClientConnection::enqueue(const ABuffer& buffer)
 {
     for (;;) {
         const_cast<ABuffer&>(buffer).shared_buffer().share_with(server_pid());
-        auto response = send_sync<ASAPI_Client::EnqueueBuffer>(buffer.shared_buffer_id());
-        if (response.success())
+        auto response = send_sync<AudioServer::EnqueueBuffer>(buffer.shared_buffer_id());
+        if (response->success())
             break;
         sleep(1);
     }
@@ -27,10 +27,10 @@ void AClientConnection::enqueue(const ABuffer& buffer)
 
 int AClientConnection::get_main_mix_volume()
 {
-    return send_sync<ASAPI_Client::GetMainMixVolume>().volume();
+    return send_sync<AudioServer::GetMainMixVolume>()->volume();
 }
 
 void AClientConnection::set_main_mix_volume(int volume)
 {
-    send_sync<ASAPI_Client::SetMainMixVolume>(volume);
+    send_sync<AudioServer::SetMainMixVolume>(volume);
 }
diff --git a/Libraries/LibAudio/AClientConnection.h b/Libraries/LibAudio/AClientConnection.h
index 3a40698dad..1978a7f00d 100644
--- a/Libraries/LibAudio/AClientConnection.h
+++ b/Libraries/LibAudio/AClientConnection.h
@@ -1,11 +1,11 @@
 #pragma once
 
-#include <LibAudio/ASAPI.h>
+#include <AudioServer/AudioServerEndpoint.h>
 #include <LibCore/CoreIPCClient.h>
 
 class ABuffer;
 
-class AClientConnection : public IPC::Client::Connection<ASAPI_ServerMessage, ASAPI_ClientMessage> {
+class AClientConnection : public IPC::Client::ConnectionNG<AudioServerEndpoint> {
     C_OBJECT(AClientConnection)
 public:
     AClientConnection();
@@ -13,8 +13,6 @@ public:
     virtual void handshake() override;
     void enqueue(const ABuffer&);
 
-    virtual void postprocess_bundles(Vector<IncomingMessageBundle>&) override {}
-
     int get_main_mix_volume();
     void set_main_mix_volume(int);
 };
diff --git a/Libraries/LibAudio/ASAPI.h b/Libraries/LibAudio/ASAPI.h
deleted file mode 100644
index 6d91f6bcef..0000000000
--- a/Libraries/LibAudio/ASAPI.h
+++ /dev/null
@@ -1,250 +0,0 @@
-#pragma once
-
-#include <AK/Assertions.h>
-
-struct ASAPI_ServerMessage {
-    enum class Type {
-        Invalid,
-        Greeting,
-        FinishedPlayingBuffer,
-        EnqueueBufferResponse,
-        DidGetMainMixVolume,
-        DidSetMainMixVolume,
-    };
-
-    Type type { Type::Invalid };
-    unsigned extra_size { 0 };
-    bool success { true };
-    int value { 0 };
-
-    union {
-        struct {
-            int server_pid;
-            int your_client_id;
-        } greeting;
-        struct {
-            int buffer_id;
-        } playing_buffer;
-    };
-};
-
-struct ASAPI_ClientMessage {
-    enum class Type {
-        Invalid,
-        Greeting,
-        EnqueueBuffer,
-        GetMainMixVolume,
-        SetMainMixVolume,
-    };
-
-    Type type { Type::Invalid };
-    unsigned extra_size { 0 };
-    int value { 0 };
-
-    union {
-        struct {
-            int client_pid;
-        } greeting;
-        struct {
-            int buffer_id;
-        } play_buffer;
-    };
-};
-
-// FIXME: Everything below this line should be generated from some kind of IPC protocol description.
-
-namespace ASAPI_Server {
-class Greeting;
-class FinishedPlayingBuffer;
-class EnqueueBufferResponse;
-class DidGetMainMixVolume;
-class DidSetMainMixVolume;
-}
-
-namespace ASAPI_Client {
-
-template<ASAPI_ClientMessage::Type type>
-class Message {
-public:
-    static ASAPI_ClientMessage::Type message_type() { return type; }
-    operator const ASAPI_ClientMessage&() const { return m_message; }
-
-protected:
-    Message()
-    {
-        m_message.type = type;
-    }
-
-    Message(const ASAPI_ClientMessage& message)
-        : m_message(message)
-    {
-        ASSERT(message.type == type);
-    }
-
-    ASAPI_ClientMessage m_message;
-};
-
-class Greeting : public Message<ASAPI_ClientMessage::Type::Greeting> {
-public:
-    typedef ASAPI_Server::Greeting ResponseType;
-    Greeting(const ASAPI_ClientMessage& message)
-        : Message(message)
-    {
-    }
-
-    Greeting(int client_pid)
-    {
-        m_message.greeting.client_pid = client_pid;
-    }
-
-    int client_pid() const { return m_message.greeting.client_pid; }
-};
-
-class EnqueueBuffer : public Message<ASAPI_ClientMessage::Type::EnqueueBuffer> {
-public:
-    typedef ASAPI_Server::EnqueueBufferResponse ResponseType;
-
-    EnqueueBuffer(const ASAPI_ClientMessage& message)
-        : Message(message)
-    {
-    }
-
-    EnqueueBuffer(int buffer_id)
-    {
-        m_message.play_buffer.buffer_id = buffer_id;
-    }
-
-    int buffer_id() const { return m_message.play_buffer.buffer_id; }
-};
-
-class GetMainMixVolume : public Message<ASAPI_ClientMessage::Type::GetMainMixVolume> {
-public:
-    typedef ASAPI_Server::DidGetMainMixVolume ResponseType;
-
-    GetMainMixVolume(const ASAPI_ClientMessage& message)
-        : Message(message)
-    {
-    }
-
-    GetMainMixVolume()
-    {
-    }
-};
-
-class SetMainMixVolume : public Message<ASAPI_ClientMessage::Type::SetMainMixVolume> {
-public:
-    typedef ASAPI_Server::DidSetMainMixVolume ResponseType;
-
-    SetMainMixVolume(const ASAPI_ClientMessage& message)
-        : Message(message)
-    {
-    }
-
-    SetMainMixVolume(int volume)
-    {
-        m_message.value = volume;
-    }
-};
-
-}
-
-namespace ASAPI_Server {
-
-template<ASAPI_ServerMessage::Type type>
-class Message {
-public:
-    static ASAPI_ServerMessage::Type message_type() { return type; }
-    operator const ASAPI_ServerMessage&() const { return m_message; }
-
-protected:
-    Message()
-    {
-        m_message.type = type;
-    }
-
-    Message(const ASAPI_ServerMessage& message)
-        : m_message(message)
-    {
-        ASSERT(message.type == type);
-    }
-
-    ASAPI_ServerMessage m_message;
-};
-
-class Greeting : public Message<ASAPI_ServerMessage::Type::Greeting> {
-public:
-    Greeting(const ASAPI_ServerMessage& message)
-        : Message(message)
-    {
-    }
-
-    Greeting(int server_pid, int your_client_id)
-    {
-        m_message.greeting.server_pid = server_pid;
-        m_message.greeting.your_client_id = your_client_id;
-    }
-
-    int server_pid() const { return m_message.greeting.server_pid; }
-    int your_client_id() const { return m_message.greeting.your_client_id; }
-};
-
-class FinishedPlayingBuffer : public Message<ASAPI_ServerMessage::Type::FinishedPlayingBuffer> {
-public:
-    FinishedPlayingBuffer(const ASAPI_ServerMessage& message)
-        : Message(message)
-    {
-    }
-
-    FinishedPlayingBuffer(int buffer_id)
-    {
-        m_message.playing_buffer.buffer_id = buffer_id;
-    }
-
-    int buffer_id() const { return m_message.playing_buffer.buffer_id; }
-};
-
-class EnqueueBufferResponse : public Message<ASAPI_ServerMessage::Type::EnqueueBufferResponse> {
-public:
-    EnqueueBufferResponse(const ASAPI_ServerMessage& message)
-        : Message(message)
-    {
-    }
-
-    EnqueueBufferResponse(bool success, int buffer_id)
-    {
-        m_message.success = success;
-        m_message.playing_buffer.buffer_id = buffer_id;
-    }
-
-    bool success() const { return m_message.success; }
-    int buffer_id() const { return m_message.playing_buffer.buffer_id; }
-};
-
-class DidGetMainMixVolume : public Message<ASAPI_ServerMessage::Type::DidGetMainMixVolume> {
-public:
-    DidGetMainMixVolume(const ASAPI_ServerMessage& message)
-        : Message(message)
-    {
-    }
-
-    DidGetMainMixVolume(int volume)
-    {
-        m_message.value = volume;
-    }
-
-    int volume() const { return m_message.value; }
-};
-
-class DidSetMainMixVolume : public Message<ASAPI_ServerMessage::Type::DidSetMainMixVolume> {
-public:
-    DidSetMainMixVolume(const ASAPI_ServerMessage& message)
-        : Message(message)
-    {
-    }
-
-    DidSetMainMixVolume()
-    {
-    }
-};
-
-}
diff --git a/Libraries/LibCore/CoreIPCClient.h b/Libraries/LibCore/CoreIPCClient.h
index c6169bf11c..f932014aca 100644
--- a/Libraries/LibCore/CoreIPCClient.h
+++ b/Libraries/LibCore/CoreIPCClient.h
@@ -1,12 +1,11 @@
 #pragma once
 
-#include <LibAudio/ASAPI.h>
 #include <LibCore/CEvent.h>
 #include <LibCore/CEventLoop.h>
 #include <LibCore/CLocalSocket.h>
 #include <LibCore/CNotifier.h>
 #include <LibCore/CSyscallUtils.h>
-
+#include <LibIPC/IMessage.h>
 #include <stdio.h>
 #include <sys/select.h>
 #include <sys/socket.h>
@@ -236,5 +235,148 @@ namespace Client {
         int m_my_client_id { -1 };
     };
 
+    template<typename Endpoint>
+    class ConnectionNG : public CObject {
+        C_OBJECT(Connection)
+    public:
+        ConnectionNG(const StringView& address)
+            : m_notifier(CNotifier(m_connection.fd(), CNotifier::Read))
+        {
+            // We want to rate-limit our clients
+            m_connection.set_blocking(true);
+            m_notifier.on_ready_to_read = [this] {
+                drain_messages_from_server();
+                CEventLoop::current().post_event(*this, make<PostProcessEvent>(m_connection.fd()));
+            };
+
+            int retries = 1000;
+            while (retries) {
+                if (m_connection.connect(CSocketAddress::local(address))) {
+                    break;
+                }
+
+                dbgprintf("Client::Connection: connect failed: %d, %s\n", errno, strerror(errno));
+                sleep(1);
+                --retries;
+            }
+            ASSERT(m_connection.is_connected());
+        }
+
+        virtual void handshake() = 0;
+
+        virtual void event(CEvent& event) override
+        {
+            if (event.type() == Event::PostProcess) {
+                postprocess_messages(m_unprocessed_messages);
+            } else {
+                CObject::event(event);
+            }
+        }
+
+        void set_server_pid(pid_t pid) { m_server_pid = pid; }
+        pid_t server_pid() const { return m_server_pid; }
+        void set_my_client_id(int id) { m_my_client_id = id; }
+        int my_client_id() const { return m_my_client_id; }
+
+        template<typename MessageType>
+        OwnPtr<MessageType> wait_for_specific_message()
+        {
+            // Double check we don't already have the event waiting for us.
+            // Otherwise we might end up blocked for a while for no reason.
+            for (ssize_t i = 0; i < m_unprocessed_messages.size(); ++i) {
+                if (m_unprocessed_messages[i]->id() == MessageType::static_message_id()) {
+                    auto message = move(m_unprocessed_messages[i]);
+                    m_unprocessed_messages.remove(i);
+                    CEventLoop::current().post_event(*this, make<PostProcessEvent>(m_connection.fd()));
+                    return message;
+                }
+            }
+            for (;;) {
+                fd_set rfds;
+                FD_ZERO(&rfds);
+                FD_SET(m_connection.fd(), &rfds);
+                int rc = CSyscallUtils::safe_syscall(select, m_connection.fd() + 1, &rfds, nullptr, nullptr, nullptr);
+                if (rc < 0) {
+                    perror("select");
+                }
+                ASSERT(rc > 0);
+                ASSERT(FD_ISSET(m_connection.fd(), &rfds));
+                bool success = drain_messages_from_server();
+                if (!success)
+                    return nullptr;
+                for (ssize_t i = 0; i < m_unprocessed_messages.size(); ++i) {
+                    if (m_unprocessed_messages[i]->id() == MessageType::static_message_id()) {
+                        auto message = move(m_unprocessed_messages[i]);
+                        m_unprocessed_messages.remove(i);
+                        CEventLoop::current().post_event(*this, make<PostProcessEvent>(m_connection.fd()));
+                        return message;
+                    }
+                }
+            }
+        }
+
+        bool post_message_to_server(const IMessage& message)
+        {
+            auto buffer = message.encode();
+            int nwritten = write(m_connection.fd(), buffer.data(), (size_t)buffer.size());
+            if (nwritten < 0) {
+                perror("write");
+                ASSERT_NOT_REACHED();
+                return false;
+            }
+            ASSERT(nwritten == buffer.size());
+            return true;
+        }
+
+        template<typename RequestType, typename... Args>
+        OwnPtr<typename RequestType::ResponseType> send_sync(Args&&... args)
+        {
+            bool success = post_message_to_server(RequestType(forward<Args>(args)...));
+            ASSERT(success);
+            auto response = wait_for_specific_message<typename RequestType::ResponseType>();
+            ASSERT(response);
+            return response;
+        }
+
+    protected:
+        virtual void postprocess_messages(Vector<OwnPtr<IMessage>>& new_bundles)
+        {
+            new_bundles.clear();
+        }
+
+    private:
+        bool drain_messages_from_server()
+        {
+            for (;;) {
+                u8 buffer[4096];
+                ssize_t nread = recv(m_connection.fd(), buffer, sizeof(buffer), MSG_DONTWAIT);
+                if (nread < 0) {
+                    if (errno == EAGAIN) {
+                        return true;
+                    }
+                    perror("read");
+                    exit(1);
+                    return false;
+                }
+                if (nread == 0) {
+                    dbg() << "EOF on IPC fd";
+                    exit(1);
+                    return false;
+                }
+
+                auto message = Endpoint::decode_message(ByteBuffer::wrap(buffer, sizeof(buffer)));
+                ASSERT(message);
+
+                m_unprocessed_messages.append(move(message));
+            }
+        }
+
+        CLocalSocket m_connection;
+        CNotifier m_notifier;
+        Vector<OwnPtr<IMessage>> m_unprocessed_messages;
+        int m_server_pid { -1 };
+        int m_my_client_id { -1 };
+    };
+
 } // Client
 } // IPC
diff --git a/Libraries/LibCore/CoreIPCServer.h b/Libraries/LibCore/CoreIPCServer.h
index 54054826c3..69a1681eb1 100644
--- a/Libraries/LibCore/CoreIPCServer.h
+++ b/Libraries/LibCore/CoreIPCServer.h
@@ -6,6 +6,8 @@
 #include <LibCore/CLocalSocket.h>
 #include <LibCore/CNotifier.h>
 #include <LibCore/CObject.h>
+#include <LibIPC/IEndpoint.h>
+#include <LibIPC/IMessage.h>
 
 #include <errno.h>
 #include <stdio.h>
@@ -52,7 +54,13 @@ namespace Server {
         auto conn = new T(AK::forward<Args>(args)...) /* arghs */;
         conn->send_greeting();
         return conn;
-    };
+    }
+
+    template<typename T, class... Args>
+    T* new_connection_ng_for_client(Args&&... args)
+    {
+        return new T(AK::forward<Args>(args)...) /* arghs */;
+    }
 
     template<typename ServerMessage, typename ClientMessage>
     class Connection : public CObject {
@@ -196,5 +204,109 @@ namespace Server {
         int m_client_pid { -1 };
     };
 
+    template<typename Endpoint>
+    class ConnectionNG : public CObject {
+        C_OBJECT(Connection)
+    public:
+        ConnectionNG(Endpoint& endpoint, CLocalSocket& socket, int client_id)
+            : m_endpoint(endpoint)
+            , m_socket(socket)
+            , m_client_id(client_id)
+        {
+            add_child(socket);
+            m_socket.on_ready_to_read = [this] { drain_client(); };
+        }
+
+        virtual ~ConnectionNG() override
+        {
+        }
+
+        void post_message(const IMessage& message)
+        {
+            auto buffer = message.encode();
+
+            int nwritten = write(m_socket.fd(), buffer.data(), (size_t)buffer.size());
+            if (nwritten < 0) {
+                switch (errno) {
+                case EPIPE:
+                    dbg() << "Connection::post_message: Disconnected from peer";
+                    delete_later();
+                    return;
+                case EAGAIN:
+                    dbg() << "Connection::post_message: Client buffer overflowed.";
+                    did_misbehave();
+                    return;
+                    break;
+                default:
+                    perror("Connection::post_message write");
+                    ASSERT_NOT_REACHED();
+                }
+            }
+
+            ASSERT(nwritten == buffer.size());
+        }
+
+        void drain_client()
+        {
+            unsigned messages_received = 0;
+            for (;;) {
+                u8 buffer[4096];
+                ssize_t nread = recv(m_socket.fd(), buffer, sizeof(buffer), MSG_DONTWAIT);
+                if (nread == 0 || (nread == -1 && errno == EAGAIN)) {
+                    if (!messages_received) {
+                        // TODO: is delete_later() sufficient?
+                        CEventLoop::current().post_event(*this, make<DisconnectedEvent>(client_id()));
+                    }
+                    break;
+                }
+                if (nread < 0) {
+                    perror("recv");
+                    ASSERT_NOT_REACHED();
+                }
+                auto message = m_endpoint.decode_message(ByteBuffer::wrap(buffer, nread));
+                if (!message) {
+                    dbg() << "drain_client: Endpoint didn't recognize message";
+                    did_misbehave();
+                    return;
+                }
+                ++messages_received;
+
+                auto response = m_endpoint.handle(*message);
+                if (response)
+                    post_message(*response);
+            }
+        }
+
+        void did_misbehave()
+        {
+            dbg() << "Connection{" << this << "} (id=" << m_client_id << ", pid=" << m_client_pid << ") misbehaved, disconnecting.";
+            m_socket.close();
+            delete_later();
+        }
+
+        int client_id() const { return m_client_id; }
+        pid_t client_pid() const { return m_client_pid; }
+        void set_client_pid(pid_t pid) { m_client_pid = pid; }
+
+    protected:
+        void event(CEvent& event) override
+        {
+            if (event.type() == Event::Disconnected) {
+                int client_id = static_cast<const DisconnectedEvent&>(event).client_id();
+                dbgprintf("Connection: Client disconnected: %d\n", client_id);
+                delete this;
+                return;
+            }
+
+            CObject::event(event);
+        }
+
+    private:
+        Endpoint& m_endpoint;
+        CLocalSocket& m_socket;
+        int m_client_id { -1 };
+        int m_client_pid { -1 };
+    };
+
 } // Server
 } // IPC