Kernel: Make Socket inherit from File.

Kernel/Devices/Device.cpp

@@ -14,7 +14,7 @@ Device::~Device()
     VFS::the().unregister_device(*this);
 }
 
-String Device::absolute_path() const
+String Device::absolute_path(FileDescriptor&) const
 {
     return String::format("device:%u,%u (%s)", m_major, m_minor, class_name());
 }

Kernel/Devices/Device.h

@@ -43,7 +43,7 @@ public:
     unsigned major() const { return m_major; }
     unsigned minor() const { return m_minor; }
 
-    virtual String absolute_path() const override;
+    virtual String absolute_path(FileDescriptor&) const override;
 
     uid_t uid() const { return m_uid; }
     uid_t gid() const { return m_gid; }

Kernel/File.h

@@ -26,7 +26,7 @@ public:
     virtual int ioctl(FileDescriptor&, unsigned request, unsigned arg);
     virtual KResultOr<Region*> mmap(Process&, LinearAddress preferred_laddr, size_t offset, size_t size);
 
-    virtual String absolute_path() const = 0;
+    virtual String absolute_path(FileDescriptor&) const = 0;
 
     virtual const char* class_name() const = 0;
 
@@ -39,6 +39,7 @@ public:
     virtual bool is_master_pty() const { return false; }
     virtual bool is_block_device() const { return false; }
     virtual bool is_character_device() const { return false; }
+    virtual bool is_socket() const { return false; }
 
 protected:
     File();

Kernel/FileSystem/FIFO.cpp

@@ -115,7 +115,7 @@ ssize_t FIFO::write(FileDescriptor&, const byte* buffer, ssize_t size)
     return m_buffer.write(buffer, size);
 }
 
-String FIFO::absolute_path() const
+String FIFO::absolute_path(FileDescriptor&) const
 {
     return String::format("fifo:%u", this);
 }

Kernel/FileSystem/FIFO.h

@@ -30,7 +30,7 @@ private:
     virtual ssize_t read(FileDescriptor&, byte*, ssize_t) override;
     virtual bool can_read(FileDescriptor&) const override;
     virtual bool can_write(FileDescriptor&) const override;
-    virtual String absolute_path() const override;
+    virtual String absolute_path(FileDescriptor&) const override;
     virtual const char* class_name() const override { return "FIFO"; }
     virtual bool is_fifo() const override { return true; }
 

Kernel/FileSystem/FileDescriptor.cpp

@@ -18,14 +18,9 @@ Retained<FileDescriptor> FileDescriptor::create(RetainPtr<Inode>&& inode)
     return adopt(*new FileDescriptor(move(inode)));
 }
 
-Retained<FileDescriptor> FileDescriptor::create(RetainPtr<File>&& file)
+Retained<FileDescriptor> FileDescriptor::create(RetainPtr<File>&& file, SocketRole role)
 {
-    return adopt(*new FileDescriptor(move(file)));
-}
-
-Retained<FileDescriptor> FileDescriptor::create(RetainPtr<Socket>&& socket, SocketRole role)
-{
-    return adopt(*new FileDescriptor(move(socket), role));
+    return adopt(*new FileDescriptor(move(file), role));
 }
 
 FileDescriptor::FileDescriptor(RetainPtr<Inode>&& inode)
@@ -33,23 +28,16 @@ FileDescriptor::FileDescriptor(RetainPtr<Inode>&& inode)
 {
 }
 
-FileDescriptor::FileDescriptor(RetainPtr<File>&& file)
+FileDescriptor::FileDescriptor(RetainPtr<File>&& file, SocketRole role)
     : m_file(move(file))
-{
-}
-
-FileDescriptor::FileDescriptor(RetainPtr<Socket>&& socket, SocketRole role)
-    : m_socket(move(socket))
 {
     set_socket_role(role);
 }
 
 FileDescriptor::~FileDescriptor()
 {
-    if (m_socket) {
-        m_socket->detach(*this);
-        m_socket = nullptr;
-    }
+    if (is_socket())
+        socket()->detach(*this);
     if (is_fifo())
         static_cast<FIFO*>(m_file.ptr())->detach(m_fifo_direction);
     if (m_file) {
@@ -64,11 +52,11 @@ void FileDescriptor::set_socket_role(SocketRole role)
     if (role == m_socket_role)
         return;
 
-    ASSERT(m_socket);
+    ASSERT(is_socket());
     if (m_socket_role != SocketRole::None)
-        m_socket->detach(*this);
+        socket()->detach(*this);
     m_socket_role = role;
-    m_socket->attach(*this);
+    socket()->attach(*this);
 }
 
 Retained<FileDescriptor> FileDescriptor::clone()
@@ -78,10 +66,7 @@ Retained<FileDescriptor> FileDescriptor::clone()
         descriptor = fifo()->open_direction(m_fifo_direction);
     } else {
         if (m_file) {
-            descriptor = FileDescriptor::create(m_file.copy_ref());
-            descriptor->m_inode = m_inode.copy_ref();
-        } else if (m_socket) {
-            descriptor = FileDescriptor::create(m_socket.copy_ref(), m_socket_role);
+            descriptor = FileDescriptor::create(m_file.copy_ref(), m_socket_role);
             descriptor->m_inode = m_inode.copy_ref();
         } else {
             descriptor = FileDescriptor::create(m_inode.copy_ref());
@@ -180,8 +165,6 @@ ssize_t FileDescriptor::read(byte* buffer, ssize_t count)
             m_current_offset += nread;
         return nread;
     }
-    if (m_socket)
-        return m_socket->read(*this, buffer, count);
     ASSERT(inode());
     ssize_t nread = inode()->read_bytes(m_current_offset, count, buffer, this);
     m_current_offset += nread;
@@ -196,8 +179,6 @@ ssize_t FileDescriptor::write(const byte* data, ssize_t size)
             m_current_offset += nwritten;
         return nwritten;
     }
-    if (m_socket)
-        return m_socket->write(*this, data, size);
     ASSERT(m_inode);
     ssize_t nwritten = m_inode->write_bytes(m_current_offset, size, data, this);
     m_current_offset += nwritten;
@@ -208,8 +189,6 @@ bool FileDescriptor::can_write()
 {
     if (m_file)
         return m_file->can_write(*this);
-    if (m_socket)
-        return m_socket->can_write(*this);
     return true;
 }
 
@@ -217,8 +196,6 @@ bool FileDescriptor::can_read()
 {
     if (m_file)
         return m_file->can_read(*this);
-    if (m_socket)
-        return m_socket->can_read(*this);
     return true;
 }
 
@@ -322,20 +299,6 @@ int FileDescriptor::close()
     return 0;
 }
 
-const char* to_string(SocketRole role)
-{
-    switch (role) {
-    case SocketRole::Listener:
-        return "Listener";
-    case SocketRole::Accepted:
-        return "Accepted";
-    case SocketRole::Connected:
-        return "Connected";
-    default:
-        return "None";
-    }
-}
-
 bool FileDescriptor::is_fsfile() const
 {
     return !is_tty() && !is_fifo() && !is_device() && !is_socket() && !is_shared_memory();
@@ -344,9 +307,7 @@ bool FileDescriptor::is_fsfile() const
 KResultOr<String> FileDescriptor::absolute_path()
 {
     if (m_file)
-        return m_file->absolute_path();
-    if (is_socket())
-        return String::format("socket:%x (role: %s)", m_socket.ptr(), to_string(m_socket_role));
+        return m_file->absolute_path(*this);
     ASSERT(m_inode);
     return VFS::the().absolute_path(*m_inode);
 }
@@ -428,3 +389,22 @@ FIFO* FileDescriptor::fifo()
         return nullptr;
     return static_cast<FIFO*>(m_file.ptr());
 }
+
+bool FileDescriptor::is_socket() const
+{
+    return m_file && m_file->is_socket();
+}
+
+Socket* FileDescriptor::socket()
+{
+    if (!is_socket())
+        return nullptr;
+    return static_cast<Socket*>(m_file.ptr());
+}
+
+const Socket* FileDescriptor::socket() const
+{
+    if (!is_socket())
+        return nullptr;
+    return static_cast<const Socket*>(m_file.ptr());
+}

Kernel/FileSystem/FileDescriptor.h

@@ -20,9 +20,8 @@ class SharedMemory;
 
 class FileDescriptor : public Retainable<FileDescriptor> {
 public:
-    static Retained<FileDescriptor> create(RetainPtr<Socket>&&, SocketRole = SocketRole::None);
     static Retained<FileDescriptor> create(RetainPtr<Inode>&&);
-    static Retained<FileDescriptor> create(RetainPtr<File>&&);
+    static Retained<FileDescriptor> create(RetainPtr<File>&&, SocketRole = SocketRole::None);
     ~FileDescriptor();
 
     Retained<FileDescriptor> clone();
@@ -74,9 +73,9 @@ public:
     dword file_flags() const { return m_file_flags; }
     void set_file_flags(dword flags) { m_file_flags = flags; }
 
-    bool is_socket() const { return m_socket; }
-    Socket* socket() { return m_socket.ptr(); }
-    const Socket* socket() const { return m_socket.ptr(); }
+    bool is_socket() const;
+    Socket* socket();
+    const Socket* socket() const;
 
     bool is_fifo() const;
     FIFO* fifo();
@@ -99,9 +98,8 @@ public:
 
 private:
     friend class VFS;
-    FileDescriptor(RetainPtr<Socket>&&, SocketRole);
+    FileDescriptor(RetainPtr<File>&&, SocketRole);
     explicit FileDescriptor(RetainPtr<Inode>&&);
-    explicit FileDescriptor(RetainPtr<File>&&);
     FileDescriptor(FIFO&, FIFO::Direction);
 
     RetainPtr<Inode> m_inode;
@@ -114,7 +112,6 @@ private:
     bool m_is_blocking { true };
     dword m_file_flags { 0 };
 
-    RetainPtr<Socket> m_socket;
     SocketRole m_socket_role { SocketRole::None };
 
     FIFO::Direction m_fifo_direction { FIFO::Neither };

Kernel/Net/IPv4Socket.h

@@ -44,6 +44,7 @@ public:
 
 protected:
     IPv4Socket(int type, int protocol);
+    virtual const char* class_name() const override { return "IPv4Socket"; }
 
     int allocate_source_port_if_needed();
 

Kernel/Net/LocalSocket.cpp

@@ -113,6 +113,8 @@ void LocalSocket::attach(FileDescriptor& descriptor)
     case SocketRole::Connecting:
         ++m_connecting_fds_open;
         break;
+    default:
+        break;
     }
 }
 
@@ -131,6 +133,8 @@ void LocalSocket::detach(FileDescriptor& descriptor)
         ASSERT(m_connecting_fds_open);
         --m_connecting_fds_open;
         break;
+    default:
+        break;
     }
 }
 

Kernel/Net/Socket.cpp

@@ -1,3 +1,4 @@
+#include <Kernel/FileSystem/FileDescriptor.h>
 #include <Kernel/Net/Socket.h>
 #include <Kernel/Net/LocalSocket.h>
 #include <Kernel/Net/IPv4Socket.h>
@@ -119,3 +120,22 @@ void Socket::load_send_deadline()
     m_send_deadline.tv_sec += (m_send_timeout.tv_usec / 1000000) * 1;
     m_send_deadline.tv_usec %= 1000000;
 }
+
+static const char* to_string(SocketRole role)
+{
+    switch (role) {
+    case SocketRole::Listener:
+        return "Listener";
+    case SocketRole::Accepted:
+        return "Accepted";
+    case SocketRole::Connected:
+        return "Connected";
+    default:
+        return "None";
+    }
+}
+
+String Socket::absolute_path(FileDescriptor& descriptor) const
+{
+    return String::format("socket:%x (role: %s)", this, to_string(descriptor.socket_role()));
+}

Kernel/Net/Socket.h

@@ -5,6 +5,7 @@
 #include <AK/RetainPtr.h>
 #include <AK/HashTable.h>
 #include <AK/Vector.h>
+#include <Kernel/File.h>
 #include <Kernel/UnixTypes.h>
 #include <Kernel/KResult.h>
 
@@ -13,10 +14,10 @@ enum class ShouldBlock { No = 0, Yes = 1 };
 
 class FileDescriptor;
 
-class Socket : public Retainable<Socket> {
+class Socket : public File {
 public:
     static KResultOr<Retained<Socket>> create(int domain, int type, int protocol);
-    virtual ~Socket();
+    virtual ~Socket() override;
 
     int domain() const { return m_domain; }
     int type() const { return m_type; }
@@ -34,10 +35,6 @@ public:
     virtual bool is_ipv4() const { return false; }
     virtual void attach(FileDescriptor&) = 0;
     virtual void detach(FileDescriptor&) = 0;
-    virtual bool can_read(FileDescriptor&) const = 0;
-    virtual ssize_t read(FileDescriptor&, byte*, ssize_t) = 0;
-    virtual ssize_t write(FileDescriptor&, const byte*, ssize_t) = 0;
-    virtual bool can_write(FileDescriptor&) const = 0;
     virtual ssize_t sendto(FileDescriptor&, const void*, size_t, int flags, const sockaddr*, socklen_t) = 0;
     virtual ssize_t recvfrom(FileDescriptor&, void*, size_t, int flags, sockaddr*, socklen_t*) = 0;
 
@@ -53,6 +50,8 @@ public:
 
     Lock& lock() { return m_lock; }
 
+    virtual String absolute_path(FileDescriptor&) const override;
+
 protected:
     Socket(int domain, int type, int protocol);
 
@@ -61,7 +60,11 @@ protected:
     void load_receive_deadline();
     void load_send_deadline();
 
+    virtual const char* class_name() const override { return "Socket"; }
+
 private:
+    virtual bool is_socket() const final { return true; }
+
     Lock m_lock { "Socket" };
     pid_t m_origin_pid { 0 };
     int m_domain { 0 };

Kernel/Net/TCPSocket.h

@@ -29,6 +29,7 @@ public:
 
 private:
     explicit TCPSocket(int protocol);
+    virtual const char* class_name() const override { return "TCPSocket"; }
 
     NetworkOrdered<word> compute_tcp_checksum(const IPv4Address& source, const IPv4Address& destination, const TCPPacket&, word payload_size);
 

Kernel/Net/UDPSocket.h

@@ -14,6 +14,7 @@ public:
 
 private:
     explicit UDPSocket(int protocol);
+    virtual const char* class_name() const override { return "UDPSocket"; }
 
     virtual int protocol_receive(const ByteBuffer&, void* buffer, size_t buffer_size, int flags, sockaddr* addr, socklen_t* addr_length) override;
     virtual int protocol_send(const void*, int) override;

Kernel/ProcessTracer.cpp

@@ -29,7 +29,7 @@ int ProcessTracer::read(FileDescriptor&, byte* buffer, int buffer_size)
     return sizeof(data);
 }
 
-String ProcessTracer::absolute_path() const
+String ProcessTracer::absolute_path(FileDescriptor&) const
 {
     return String::format("tracer:%d", m_pid);
 }

Kernel/ProcessTracer.h

@@ -18,7 +18,7 @@ public:
     virtual bool can_write(FileDescriptor&) const override { return true; }
     virtual int write(FileDescriptor&, const byte*, int) override { return -EIO; }
 
-    virtual String absolute_path() const override;
+    virtual String absolute_path(FileDescriptor&) const override;
 
     void did_syscall(dword function, dword arg1, dword arg2, dword arg3, dword result);
     pid_t pid() const { return m_pid; }

Kernel/SharedMemory.cpp

@@ -68,7 +68,7 @@ KResult SharedMemory::truncate(int length)
     return KResult(-ENOTIMPL);
 }
 
-String SharedMemory::absolute_path() const
+String SharedMemory::absolute_path(FileDescriptor&) const
 {
     return String::format("shm:%u", this);
 }

Kernel/SharedMemory.h

@@ -28,7 +28,7 @@ private:
     virtual bool can_write(FileDescriptor&) const override { return true; }
     virtual int read(FileDescriptor&, byte*, int) override;
     virtual int write(FileDescriptor&, const byte*, int) override;
-    virtual String absolute_path() const override;
+    virtual String absolute_path(FileDescriptor&) const override;
     virtual const char* class_name() const override { return "SharedMemory"; }
     virtual bool is_shared_memory() const override { return true; }
 

Kernel/TTY/TTY.h

@@ -15,7 +15,7 @@ public:
     virtual bool can_read(FileDescriptor&) const override;
     virtual bool can_write(FileDescriptor&) const override;
     virtual int ioctl(FileDescriptor&, unsigned request, unsigned arg) override final;
-    virtual String absolute_path() const override { return tty_name(); }
+    virtual String absolute_path(FileDescriptor&) const override { return tty_name(); }
 
     virtual String tty_name() const = 0;