Add an fd field to FileHandle in Kernel builds.

VirtualFileSystem/FileHandle.h

@@ -14,11 +14,20 @@ public:
 
     ByteBuffer readEntireFile();
 
+#ifdef SERENITY_KERNEL
+    int fd() const { return m_fd; }
+    void setFD(int fd) { m_fd = fd; }
+#endif
+
 private:
     friend class VirtualFileSystem;
 
     RetainPtr<VirtualFileSystem::Node> m_vnode;
 
     Unix::off_t m_currentOffset { 0 };
+
+#ifdef SERENITY_KERNEL
+    int m_fd { -1 };
+#endif
 };
 

VirtualFileSystem/VirtualFileSystem.cpp

@@ -12,8 +12,17 @@ static dword encodedDevice(unsigned major, unsigned minor)
     return (minor & 0xff) | (major << 8) | ((minor & ~0xff) << 12);
 }
 
+static VirtualFileSystem* s_the;
+
+VirtualFileSystem& VirtualFileSystem::the()
+{
+    ASSERT(s_the);
+    return *s_the;
+}
+
 VirtualFileSystem::VirtualFileSystem()
 {
+    s_the = this;
     m_maxNodeCount = 16;
     m_nodes = reinterpret_cast<Node*>(kmalloc(sizeof(Node) * maxNodeCount()));
     memset(m_nodes, 0, sizeof(Node) * maxNodeCount());

VirtualFileSystem/VirtualFileSystem.h

@@ -35,6 +35,8 @@ public:
         CharacterDevice* m_characterDevice { nullptr };
     };
 
+    static VirtualFileSystem& the();
+
     VirtualFileSystem();
     ~VirtualFileSystem();