Mark one-parameter constructors as explicit & use override where possible

This commit marks (hopefully) ever one-parameter constructor as explicit.

It also uses override in (hopefully) all circumstances where a virtual
method is overridden.

There are a very few other minor changes - most of them were necessary
to get everything to compile (like one additional constructor). In one
case I changed an implicit operation to an explicit string conversion -
I think the automatically chosen conversion was much more convoluted.

This took longer than I want to admit but not as long as I feared :)

src/iosource/Component.h

@@ -27,12 +27,12 @@ public:
 	 * @param name A descriptive name for the component.  This name must
 	 * be unique across all components of this type.
 	 */
-	Component(const std::string& name);
+	explicit Component(const std::string& name);
 
 	/**
 	 * Destructor.
 	 */
-	~Component();
+	~Component() override;
 
 protected:
 	/**
@@ -80,7 +80,7 @@ public:
 	/**
 	 * Destructor.
 	 */
-	virtual ~PktSrcComponent();
+	~PktSrcComponent() override;
 
 	/**
 	 * Returns the prefix(es) passed to the constructor.
@@ -113,7 +113,7 @@ public:
 	 * Generates a human-readable description of the component. This goes
 	 * into the output of \c "bro -NN".
 	 */
-	virtual void DoDescribe(ODesc* d) const;
+	void DoDescribe(ODesc* d) const override;
 
 private:
 	std::vector<std::string> prefixes;
@@ -139,7 +139,7 @@ public:
 	/**
 	 * Destructor.
 	 */
-	~PktDumperComponent();
+	~PktDumperComponent() override;
 
 	/**
 	 * Returns the prefix(es) passed to the constructor.
@@ -160,7 +160,7 @@ public:
 	 * Generates a human-readable description of the component. This goes
 	 * into the output of \c "bro -NN".
 	 */
-	virtual void DoDescribe(ODesc* d) const;
+	void DoDescribe(ODesc* d) const override;
 
 private:
 	std::vector<std::string> prefixes;

src/iosource/PktSrc.h

@@ -57,7 +57,7 @@ public:
 	/**
 	 * Destructor.
 	 */
-	virtual ~PktSrc();
+	~PktSrc() override;
 
 	/**
 	 * Returns the path associated with the source. This is the interface
@@ -345,13 +345,13 @@ private:
 	bool ExtractNextPacketInternal();
 
 	// IOSource interface implementation.
-	virtual void Init();
-	virtual void Done();
-	virtual void GetFds(iosource::FD_Set* read, iosource::FD_Set* write,
-	                    iosource::FD_Set* except);
-	virtual double NextTimestamp(double* local_network_time);
-	virtual void Process();
-	virtual const char* Tag();
+	void Init() override;
+	void Done() override;
+	void GetFds(iosource::FD_Set* read, iosource::FD_Set* write,
+	                    iosource::FD_Set* except) override;
+	double NextTimestamp(double* local_network_time) override;
+	void Process() override;
+	const char* Tag() override;
 
 	Properties props;
 

src/iosource/pcap/Dumper.h

@@ -15,15 +15,15 @@ namespace pcap {
 class PcapDumper : public PktDumper {
 public:
 	PcapDumper(const std::string& path, bool append);
-	virtual ~PcapDumper();
+	~PcapDumper() override;
 
 	static PktDumper* Instantiate(const std::string& path, bool appen);
 
 protected:
 	// PktDumper interface.
-	virtual void Open();
-	virtual void Close();
-	virtual bool Dump(const Packet* pkt);
+	void Open() override;
+	void Close() override;
+	bool Dump(const Packet* pkt) override;
 
 private:
 	Properties props;

src/iosource/pcap/Source.h

@@ -11,19 +11,19 @@ namespace pcap {
 class PcapSource : public iosource::PktSrc {
 public:
 	PcapSource(const std::string& path, bool is_live);
-	virtual ~PcapSource();
+	~PcapSource() override;
 
 	static PktSrc* Instantiate(const std::string& path, bool is_live);
 
 protected:
 	// PktSrc interface.
-	virtual void Open();
-	virtual void Close();
-	virtual bool ExtractNextPacket(Packet* pkt);
-	virtual void DoneWithPacket();
-	virtual bool PrecompileFilter(int index, const std::string& filter);
-	virtual bool SetFilter(int index);
-	virtual void Statistics(Stats* stats);
+	void Open() override;
+	void Close() override;
+	bool ExtractNextPacket(Packet* pkt) override;
+	void DoneWithPacket() override;
+	bool PrecompileFilter(int index, const std::string& filter) override;
+	bool SetFilter(int index) override;
+	void Statistics(Stats* stats) override;
 
 private:
 	void OpenLive();