Start working on a Downloader app and backing classes in LibGUI.

LibGUI is slowly becoming LibKitchensink but I'm okay with this for now.

Applications/Downloader/.gitignore

@@ -0,0 +1,3 @@
+*.o
+*.d
+Downloader

Applications/Downloader/Makefile

@@ -0,0 +1,32 @@
+OBJS = \
+    main.o
+
+APP = Downloader
+
+STANDARD_FLAGS = -std=c++17 -Wno-sized-deallocation
+WARNING_FLAGS = -Wextra -Wall -Wundef -Wcast-qual -Wwrite-strings -Wimplicit-fallthrough
+FLAVOR_FLAGS = -fno-exceptions -fno-rtti
+OPTIMIZATION_FLAGS = -Os
+INCLUDE_FLAGS = -I../../Servers -I../.. -I. -I../../LibC
+
+DEFINES = -DSERENITY -DSANITIZE_PTRS -DUSERLAND
+
+CXXFLAGS = -MMD -MP $(WARNING_FLAGS) $(OPTIMIZATION_FLAGS) $(FLAVOR_FLAGS) $(STANDARD_FLAGS) $(INCLUDE_FLAGS) $(DEFINES)
+CXX = i686-pc-serenity-g++
+LD = i686-pc-serenity-g++
+AR = i686-pc-serenity-ar
+LDFLAGS = -L../../LibC -L../../LibGUI
+
+all: $(APP)
+
+$(APP): $(OBJS)
+	$(LD) -o $(APP) $(LDFLAGS) $(OBJS) -lgui -lc
+
+.cpp.o:
+	@echo "CXX $<"; $(CXX) $(CXXFLAGS) -o $@ -c $<
+
+-include $(OBJS:%.o=%.d)
+
+clean:
+	@echo "CLEAN"; rm -f $(APPS) $(OBJS) *.d
+

Applications/Downloader/main.cpp

@@ -0,0 +1,30 @@
+#include <LibGUI/GApplication.h>
+#include <LibGUI/GHttpRequest.h>
+#include <LibGUI/GHttpResponse.h>
+#include <LibGUI/GNetworkJob.h>
+#include <stdio.h>
+
+int main(int argc, char** argv)
+{
+    GApplication app(argc, argv);
+
+    GHttpRequest request;
+    request.set_hostname("www.google.com");
+    request.set_path("/");
+
+    auto job = request.schedule();
+    job->on_finish = [&job] (bool success) {
+        if (!success) {
+            dbgprintf("on_finish: request failed :(\n");
+            return;
+        }
+        auto& response = static_cast<const GHttpResponse&>(*job->response());
+        printf("on_receive: code=%d\n", response.code());
+        printf("payload:\n");
+        printf("%s", response.payload().pointer());
+        printf("payload was %d bytes\n", response.payload().size());
+    };
+
+    printf("Entering main loop...\n");
+    return app.exec();
+}

Kernel/makeall.sh

@@ -36,6 +36,8 @@ $make_cmd -C ../Applications/IRCClient clean && \
 $make_cmd -C ../Applications/IRCClient && \
 $make_cmd -C ../Applications/Taskbar clean && \
 $make_cmd -C ../Applications/Taskbar && \
+$make_cmd -C ../Applications/Downloader clean && \
+$make_cmd -C ../Applications/Downloader && \
 $make_cmd clean &&\
 $make_cmd && \
 sudo ./sync.sh

Kernel/sync.sh

@@ -94,6 +94,8 @@ cp -v ../Servers/LookupServer/LookupServer mnt/bin/LookupServer
 cp -v ../Servers/WindowServer/WindowServer mnt/bin/WindowServer
 cp -v ../Applications/Taskbar/Taskbar mnt/bin/Taskbar
 ln -s Taskbar mnt/bin/tb
+cp -v ../Applications/Downloader/Downloader mnt/bin/Downloader
+ln -s Downloader mnt/bin/dl
 cp -v kernel.map mnt/
 sh sync-local.sh
 umount mnt || ( sleep 0.5 && sync && umount mnt )

LibGUI/GEvent.h

@@ -5,6 +5,7 @@
 #include <AK/AKString.h>
 #include <AK/Types.h>
 #include <AK/WeakPtr.h>
+#include <AK/Function.h>
 #include <Kernel/KeyCode.h>
 #include <LibGUI/GWindowType.h>
 
@@ -28,6 +29,7 @@ public:
         KeyUp,
         Timer,
         DeferredDestroy,
+        DeferredInvoke,
         WindowEntered,
         WindowLeft,
         WindowBecameInactive,
@@ -55,6 +57,19 @@ private:
     Type m_type { Invalid };
 };
 
+class GDeferredInvocationEvent : public GEvent {
+    friend class GEventLoop;
+public:
+    GDeferredInvocationEvent(Function<void(GObject&)> invokee)
+        : GEvent(GEvent::Type::DeferredInvoke)
+        , m_invokee(move(invokee))
+    {
+    }
+
+private:
+    Function<void(GObject&)> m_invokee;
+};
+
 class GWMEvent : public GEvent {
 public:
     GWMEvent(Type type, int client_id, int window_id)

LibGUI/GEventLoop.cpp

@@ -158,6 +158,9 @@ int GEventLoop::exec()
                 default:
                     dbgprintf("Event type %u with no receiver :(\n", event.type());
                 }
+            } else if (event.type() == GEvent::Type::DeferredInvoke) {
+                printf("DeferredInvoke: receiver=%s{%p}\n", receiver->class_name(), receiver);
+                static_cast<GDeferredInvocationEvent&>(event).m_invokee(*receiver);
             } else {
                 receiver->event(event);
             }

LibGUI/GHttpNetworkJob.cpp

@@ -0,0 +1,47 @@
+#include <LibGUI/GHttpNetworkJob.h>
+#include <LibGUI/GHttpResponse.h>
+#include <LibGUI/GTCPSocket.h>
+#include <stdio.h>
+
+GHttpNetworkJob::GHttpNetworkJob(const GHttpRequest& request)
+    : m_request(request)
+{
+}
+
+GHttpNetworkJob::~GHttpNetworkJob()
+{
+}
+
+void GHttpNetworkJob::start()
+{
+    ASSERT(!m_socket);
+    m_socket = new GTCPSocket(this);
+    int success = m_socket->connect(m_request.hostname(), m_request.port());
+    if (!success)
+        return did_fail(GNetworkJob::Error::ConnectionFailed);
+
+    auto raw_request = m_request.to_raw_request();
+
+    printf("raw_request:\n%s\n", raw_request.pointer());
+
+    success = m_socket->send(raw_request);
+    if (!success)
+        return did_fail(GNetworkJob::Error::TransmissionFailed);
+
+    Vector<byte> buffer;
+    while (m_socket->is_connected()) {
+        auto payload = m_socket->receive(100000);
+        if (!payload) {
+            if (m_socket->eof())
+                break;
+            return did_fail(GNetworkJob::Error::TransmissionFailed);
+        }
+        buffer.append(payload.pointer(), payload.size());
+    }
+
+    auto response = GHttpResponse::create(1, ByteBuffer::copy(buffer.data(), buffer.size()));
+    deferred_invoke([this, response] (GObject&) {
+        printf("in the deferred invoke lambda\n");
+        did_finish(move(response));
+    });
+}

LibGUI/GHttpNetworkJob.h

@@ -0,0 +1,20 @@
+#pragma once
+
+#include <LibGUI/GNetworkJob.h>
+#include <LibGUI/GHttpRequest.h>
+
+class GTCPSocket;
+
+class GHttpNetworkJob final : public GNetworkJob {
+public:
+    explicit GHttpNetworkJob(const GHttpRequest&);
+    virtual ~GHttpNetworkJob() override;
+
+    virtual void start() override;
+
+    virtual const char* class_name() const override { return "GHttpNetworkJob"; }
+
+private:
+    GHttpRequest m_request;
+    GTCPSocket* m_socket { nullptr };
+};

LibGUI/GHttpRequest.cpp

@@ -0,0 +1,45 @@
+#include <LibGUI/GHttpRequest.h>
+#include <LibGUI/GHttpNetworkJob.h>
+#include <LibGUI/GEventLoop.h>
+#include <AK/StringBuilder.h>
+
+GHttpRequest::GHttpRequest()
+{
+}
+
+GHttpRequest::~GHttpRequest()
+{
+}
+
+GNetworkJob* GHttpRequest::schedule()
+{
+    auto* job = new GHttpNetworkJob(*this);
+    job->start();
+    return job;
+}
+
+String GHttpRequest::method_name() const
+{
+    switch (m_method) {
+    case Method::GET:
+        return "GET";
+    case Method::HEAD:
+        return "HEAD";
+    case Method::POST:
+        return "POST";
+    default:
+        ASSERT_NOT_REACHED();
+    }
+}
+
+ByteBuffer GHttpRequest::to_raw_request() const
+{
+    StringBuilder builder;
+    builder.append(method_name());
+    builder.append(' ');
+    builder.append(m_path);
+    builder.append(" HTTP/1.0\nHost: ");
+    builder.append(m_hostname);
+    builder.append("\n\n");
+    return builder.to_byte_buffer();
+}

LibGUI/GHttpRequest.h

@@ -0,0 +1,34 @@
+#pragma once
+
+#include <AK/AKString.h>
+
+class GNetworkJob;
+
+class GHttpRequest {
+public:
+    enum Method { Invalid, HEAD, GET, POST };
+
+    GHttpRequest();
+    ~GHttpRequest();
+
+    String hostname() const { return m_hostname; }
+    int port() const { return m_port; }
+    String path() const { return m_path; }
+    Method method() const { return m_method; }
+
+    void set_hostname(const String& hostname) { m_hostname = hostname; }
+    void set_port(int port) { m_port = port; }
+    void set_path(const String& path) { m_path = path; }
+    void set_method(Method method) { m_method = method; }
+
+    String method_name() const;
+    ByteBuffer to_raw_request() const;
+
+    GNetworkJob* schedule();
+
+private:
+    String m_hostname;
+    String m_path;
+    int m_port { 80 };
+    Method m_method { GET };
+};

LibGUI/GHttpResponse.cpp

@@ -0,0 +1,11 @@
+#include <LibGUI/GHttpResponse.h>
+
+GHttpResponse::GHttpResponse(int code, ByteBuffer&& payload)
+    : GNetworkResponse(move(payload))
+    , m_code(code)
+{
+}
+
+GHttpResponse::~GHttpResponse()
+{
+}

LibGUI/GHttpResponse.h

@@ -0,0 +1,23 @@
+#pragma once
+
+#include <LibGUI/GNetworkResponse.h>
+#include <AK/AKString.h>
+#include <AK/HashMap.h>
+
+class GHttpResponse : public GNetworkResponse {
+public:
+    virtual ~GHttpResponse() override;
+    static Retained<GHttpResponse> create(int code, ByteBuffer&& payload)
+    {
+        return adopt(*new GHttpResponse(code, move(payload)));
+    }
+
+    int code() const { return m_code; }
+    const HashMap<String, String>& headers() const { return m_headers; }
+
+private:
+    GHttpResponse(int code, ByteBuffer&&);
+
+    int m_code { 0 };
+    HashMap<String, String> m_headers;
+};

LibGUI/GIODevice.cpp

@@ -42,6 +42,10 @@ ByteBuffer GIODevice::read(int max_size)
         set_error(errno);
         return { };
     }
+    if (nread == 0) {
+        set_eof(true);
+        return { };
+    }
     buffer.trim(nread);
     return buffer;
 }

LibGUI/GNetworkJob.cpp

@@ -0,0 +1,27 @@
+#include <LibGUI/GNetworkJob.h>
+#include <LibGUI/GNetworkResponse.h>
+#include <stdio.h>
+
+GNetworkJob::GNetworkJob()
+{
+}
+
+GNetworkJob::~GNetworkJob()
+{
+}
+
+void GNetworkJob::did_finish(Retained<GNetworkResponse>&& response)
+{
+    m_response = move(response);
+    printf("%s{%p} job did_finish!\n", class_name(), this);
+    ASSERT(on_finish);
+    on_finish(true);
+}
+
+void GNetworkJob::did_fail(Error error)
+{
+    m_error = error;
+    dbgprintf("%s{%} job did_fail! error=%u\n", class_name(), this, (unsigned)error);
+    ASSERT(on_finish);
+    on_finish(false);
+}

LibGUI/GNetworkJob.h

@@ -0,0 +1,36 @@
+#pragma once
+
+#include <LibGUI/GObject.h>
+#include <AK/Function.h>
+
+class GNetworkResponse;
+
+class GNetworkJob : public GObject {
+public:
+    enum class Error {
+        None,
+        ConnectionFailed,
+        TransmissionFailed,
+    };
+    virtual ~GNetworkJob() override;
+
+    Function<void(bool success)> on_finish;
+
+    bool has_error() const { return m_error != Error::None; }
+    Error error() const { return m_error; }
+    GNetworkResponse* response() { return m_response.ptr(); }
+    const GNetworkResponse* response() const { return m_response.ptr(); }
+
+    virtual void start() = 0;
+
+    virtual const char* class_name() const override { return "GNetworkJob"; }
+
+protected:
+    GNetworkJob();
+    void did_finish(Retained<GNetworkResponse>&&);
+    void did_fail(Error);
+
+private:
+    RetainPtr<GNetworkResponse> m_response;
+    Error m_error { Error::None };
+};

LibGUI/GNetworkResponse.cpp

@@ -0,0 +1,10 @@
+#include <LibGUI/GNetworkResponse.h>
+
+GNetworkResponse::GNetworkResponse(ByteBuffer&& payload)
+    : m_payload(payload)
+{
+}
+
+GNetworkResponse::~GNetworkResponse()
+{
+}

LibGUI/GNetworkResponse.h

@@ -0,0 +1,18 @@
+#pragma once
+
+#include <AK/Retainable.h>
+#include <AK/ByteBuffer.h>
+
+class GNetworkResponse : public Retainable<GNetworkResponse> {
+public:
+    virtual ~GNetworkResponse();
+
+    bool is_error() const { return m_error; }
+    const ByteBuffer& payload() const { return m_payload; }
+
+protected:
+    explicit GNetworkResponse(ByteBuffer&&);
+
+    bool m_error { false };
+    ByteBuffer m_payload;
+};

LibGUI/GObject.cpp

@@ -99,5 +99,9 @@ void GObject::dump_tree(int indent)
     for (auto* child : children()) {
         child->dump_tree(indent + 2);
     }
-
+}
+
+void GObject::deferred_invoke(Function<void(GObject&)> invokee)
+{
+    GEventLoop::current().post_event(*this, make<GDeferredInvocationEvent>(move(invokee)));
 }

LibGUI/GObject.h

@@ -1,5 +1,6 @@
 #pragma once
 
+#include <AK/Function.h>
 #include <AK/Vector.h>
 #include <AK/Weakable.h>
 
@@ -32,6 +33,8 @@ public:
 
     void dump_tree(int indent = 0);
 
+    void deferred_invoke(Function<void(GObject&)>);
+
     virtual bool is_widget() const { return false; }
     virtual bool is_window() const { return false; }
 

LibGUI/Makefile

@@ -58,6 +58,11 @@ LIBGUI_OBJS = \
     GFileSystemModel.o \
     GSplitter.o \
     GTimer.o \
+    GNetworkJob.o \
+    GNetworkResponse.o \
+    GHttpRequest.o \
+    GHttpResponse.o \
+    GHttpNetworkJob.o \
     GWindow.o
 
 OBJS = $(SHAREDGRAPHICS_OBJS) $(LIBGUI_OBJS)