Reworking log writer API to make it easier to pass additional

information to a writer's initialization method.

However, for now the information provided is still the same.

src/RemoteSerializer.cc

@@ -2503,17 +2503,17 @@ bool RemoteSerializer::ProcessRemotePrint()
 	return true;
 	}
 
-bool RemoteSerializer::SendLogCreateWriter(EnumVal* id, EnumVal* writer, string path, int num_fields, const threading::Field* const * fields)
+bool RemoteSerializer::SendLogCreateWriter(EnumVal* id, EnumVal* writer, const logging::WriterBackend::WriterInfo& info, int num_fields, const threading::Field* const * fields)
 	{
 	loop_over_list(peers, i)
 		{
-		SendLogCreateWriter(peers[i]->id, id, writer, path, num_fields, fields);
+		SendLogCreateWriter(peers[i]->id, id, writer, info, num_fields, fields);
 		}
 
 	return true;
 	}
 
-bool RemoteSerializer::SendLogCreateWriter(PeerID peer_id, EnumVal* id, EnumVal* writer, string path, int num_fields, const threading::Field* const * fields)
+bool RemoteSerializer::SendLogCreateWriter(PeerID peer_id, EnumVal* id, EnumVal* writer, const logging::WriterBackend::WriterInfo& info, int num_fields, const threading::Field* const * fields)
 	{
 	SetErrorDescr("logging");
 
@@ -2535,8 +2535,8 @@ bool RemoteSerializer::SendLogCreateWriter(PeerID peer_id, EnumVal* id, EnumVal*
 
 	bool success = fmt.Write(id->AsEnum(), "id") &&
 		fmt.Write(writer->AsEnum(), "writer") &&
-		fmt.Write(path, "path") &&
+		fmt.Write(num_fields, "num_fields") &&
-		fmt.Write(num_fields, "num_fields");
+		info.Write(&fmt);
 
 	if ( ! success )
 		goto error;
@@ -2691,13 +2691,13 @@ bool RemoteSerializer::ProcessLogCreateWriter()
 	fmt.StartRead(current_args->data, current_args->len);
 
 	int id, writer;
-	string path;
 	int num_fields;
+	logging::WriterBackend::WriterInfo info;
 
 	bool success = fmt.Read(&id, "id") &&
 		fmt.Read(&writer, "writer") &&
-		fmt.Read(&path, "path") &&
+		fmt.Read(&num_fields, "num_fields") &&
-		fmt.Read(&num_fields, "num_fields");
+		info.Read(&fmt);
 
 	if ( ! success )
 		goto error;
@@ -2716,7 +2716,7 @@ bool RemoteSerializer::ProcessLogCreateWriter()
 	id_val = new EnumVal(id, BifType::Enum::Log::ID);
 	writer_val = new EnumVal(writer, BifType::Enum::Log::Writer);
 
-	if ( ! log_mgr->CreateWriter(id_val, writer_val, path, num_fields, fields, true, false) )
+	if ( ! log_mgr->CreateWriter(id_val, writer_val, info, num_fields, fields, true, false) )
 		goto error;
 
 	Unref(id_val);

src/RemoteSerializer.h

@@ -9,6 +9,7 @@
 #include "IOSource.h"
 #include "Stats.h"
 #include "File.h"
+#include "logging/WriterBackend.h"
 
 #include <vector>
 #include <string>
@@ -104,10 +105,10 @@ public:
 	bool SendPrintHookEvent(BroFile* f, const char* txt, size_t len);
 
 	// Send a request to create a writer on a remote side.
-	bool SendLogCreateWriter(PeerID peer, EnumVal* id, EnumVal* writer, string path, int num_fields, const threading::Field* const * fields);
+	bool SendLogCreateWriter(PeerID peer, EnumVal* id, EnumVal* writer, const logging::WriterBackend::WriterInfo& info, int num_fields, const threading::Field* const * fields);
 
 	// Broadcasts a request to create a writer.
-	bool SendLogCreateWriter(EnumVal* id, EnumVal* writer, string path, int num_fields, const threading::Field* const * fields);
+	bool SendLogCreateWriter(EnumVal* id, EnumVal* writer, const logging::WriterBackend::WriterInfo& info, int num_fields, const threading::Field* const * fields);
 
 	// Broadcast a log entry to everybody interested.
 	bool SendLogWrite(EnumVal* id, EnumVal* writer, string path, int num_fields, const threading::Value* const * vals);

src/logging/Manager.cc

@@ -74,6 +74,7 @@ struct Manager::WriterInfo {
 	double interval;
 	Func* postprocessor;
 	WriterFrontend* writer;
+	WriterBackend::WriterInfo info;
 	};
 
 struct Manager::Stream {
@@ -764,8 +765,11 @@ bool Manager::Write(EnumVal* id, RecordVal* columns)
 			for ( int j = 0; j < filter->num_fields; ++j )
 				arg_fields[j] = new threading::Field(*filter->fields[j]);
 
+			WriterBackend::WriterInfo info;
+			info.path = path;
+
 			writer = CreateWriter(stream->id, filter->writer,
-					      path, filter->num_fields,
+					      info, filter->num_fields,
 					      arg_fields, filter->local, filter->remote);
 
 			if ( ! writer )
@@ -953,7 +957,7 @@ threading::Value** Manager::RecordToFilterVals(Stream* stream, Filter* filter,
 	return vals;
 	}
 
-WriterFrontend* Manager::CreateWriter(EnumVal* id, EnumVal* writer, string path,
+WriterFrontend* Manager::CreateWriter(EnumVal* id, EnumVal* writer, const WriterBackend::WriterInfo& info,
 				int num_fields, const threading::Field* const*  fields, bool local, bool remote)
 	{
 	Stream* stream = FindStream(id);
@@ -963,7 +967,7 @@ WriterFrontend* Manager::CreateWriter(EnumVal* id, EnumVal* writer, string path,
 		return false;
 
 	Stream::WriterMap::iterator w =
-		stream->writers.find(Stream::WriterPathPair(writer->AsEnum(), path));
+		stream->writers.find(Stream::WriterPathPair(writer->AsEnum(), info.path));
 
 	if ( w != stream->writers.end() )
 		// If we already have a writer for this. That's fine, we just
@@ -973,7 +977,7 @@ WriterFrontend* Manager::CreateWriter(EnumVal* id, EnumVal* writer, string path,
 	WriterFrontend* writer_obj = new WriterFrontend(id, writer, local, remote);
 	assert(writer_obj);
 
-	writer_obj->Init(path, num_fields, fields);
+	writer_obj->Init(info, num_fields, fields);
 
 	WriterInfo* winfo = new WriterInfo;
 	winfo->type = writer->Ref()->AsEnumVal();
@@ -982,6 +986,7 @@ WriterFrontend* Manager::CreateWriter(EnumVal* id, EnumVal* writer, string path,
 	winfo->rotation_timer = 0;
 	winfo->interval = 0;
 	winfo->postprocessor = 0;
+	winfo->info = info;
 
 	// Search for a corresponding filter for the writer/path pair and use its
 	// rotation settings.  If no matching filter is found, fall back on
@@ -993,7 +998,7 @@ WriterFrontend* Manager::CreateWriter(EnumVal* id, EnumVal* writer, string path,
 		{
 		Filter* f = *it;
 		if ( f->writer->AsEnum() == writer->AsEnum() &&
-		     f->path == winfo->writer->Path() )
+		     f->path == winfo->writer->info.path )
 			{
 			found_filter_match = true;
 			winfo->interval = f->interval;
@@ -1012,7 +1017,7 @@ WriterFrontend* Manager::CreateWriter(EnumVal* id, EnumVal* writer, string path,
 	InstallRotationTimer(winfo);
 
 	stream->writers.insert(
-		Stream::WriterMap::value_type(Stream::WriterPathPair(writer->AsEnum(), path),
+		Stream::WriterMap::value_type(Stream::WriterPathPair(writer->AsEnum(), info.path),
 		winfo));
 
 	return writer_obj;
@@ -1093,7 +1098,7 @@ void Manager::SendAllWritersTo(RemoteSerializer::PeerID peer)
 			EnumVal writer_val(i->first.first, BifType::Enum::Log::Writer);
 			remote_serializer->SendLogCreateWriter(peer, (*s)->id,
 							       &writer_val,
-							       i->first.second,
+							       i->second->info,
 							       writer->NumFields(),
 							       writer->Fields());
 			}
@@ -1246,7 +1251,7 @@ void Manager::Rotate(WriterInfo* winfo)
 	localtime_r(&teatime, &tm);
 	strftime(buf, sizeof(buf), date_fmt, &tm);
 
-	string tmp = string(fmt("%s-%s", winfo->writer->Path().c_str(), buf));
+	string tmp = string(fmt("%s-%s", winfo->writer->Info().path.c_str(), buf));
 
 	// Trigger the rotation.
 	winfo->writer->Rotate(tmp, winfo->open_time, network_time, terminating);
@@ -1274,7 +1279,7 @@ bool Manager::FinishedRotation(WriterFrontend* writer, string new_name, string o
 	RecordVal* info = new RecordVal(BifType::Record::Log::RotationInfo);
 	info->Assign(0, winfo->type->Ref());
 	info->Assign(1, new StringVal(new_name.c_str()));
-	info->Assign(2, new StringVal(winfo->writer->Path().c_str()));
+	info->Assign(2, new StringVal(winfo->writer->Info().path.c_str()));
 	info->Assign(3, new Val(open, TYPE_TIME));
 	info->Assign(4, new Val(close, TYPE_TIME));
 	info->Assign(5, new Val(terminating, TYPE_BOOL));

src/logging/Manager.h

@@ -9,13 +9,14 @@
 #include "../EventHandler.h"
 #include "../RemoteSerializer.h"
 
+#include "WriterBackend.h"
+
 class SerializationFormat;
 class RemoteSerializer;
 class RotationTimer;
 
 namespace logging {
 
-class WriterBackend;
 class WriterFrontend;
 class RotationFinishedMessage;
 
@@ -162,7 +163,7 @@ protected:
 	//// Function also used by the RemoteSerializer.
 
 	// Takes ownership of fields.
-	WriterFrontend* CreateWriter(EnumVal* id, EnumVal* writer, string path,
+	WriterFrontend* CreateWriter(EnumVal* id, EnumVal* writer, const WriterBackend::WriterInfo& info,
 				int num_fields, const threading::Field* const* fields,
 				bool local, bool remote);
 

src/logging/WriterBackend.cc

@@ -4,6 +4,7 @@
 #include "bro_inet_ntop.h"
 #include "threading/SerialTypes.h"
 
+#include "Manager.h"
 #include "WriterBackend.h"
 #include "WriterFrontend.h"
 
@@ -60,14 +61,25 @@ public:
 
 using namespace logging;
 
+bool WriterBackend::WriterInfo::Read(SerializationFormat* fmt)
+	{
+	return fmt->Read(&path, "path");
+	}
+
+bool WriterBackend::WriterInfo::Write(SerializationFormat* fmt) const
+	{
+	return fmt->Write(path, "path");
+	}
+
 WriterBackend::WriterBackend(WriterFrontend* arg_frontend) : MsgThread()
 	{
-	path = "<path not yet set>";
 	num_fields = 0;
 	fields = 0;
 	buffering = true;
 	frontend = arg_frontend;
 
+	info.path = "<path not yet set>";
+
 	SetName(frontend->Name());
 	}
 
@@ -108,17 +120,17 @@ void WriterBackend::DisableFrontend()
 	SendOut(new DisableMessage(frontend));
 	}
 
-bool WriterBackend::Init(string arg_path, int arg_num_fields, const Field* const*  arg_fields)
+bool WriterBackend::Init(const WriterInfo& arg_info, int arg_num_fields, const Field* const*  arg_fields)
 	{
-	path = arg_path;
+	info = arg_info;
 	num_fields = arg_num_fields;
 	fields = arg_fields;
 
-	string name = Fmt("%s/%s", path.c_str(), frontend->Name().c_str());
+	string name = Fmt("%s/%s", info.path.c_str(), frontend->Name().c_str());
 
 	SetName(name);
 
-	if ( ! DoInit(arg_path, arg_num_fields, arg_fields) )
+	if ( ! DoInit(arg_info, arg_num_fields, arg_fields) )
 		{
 		DisableFrontend();
 		return false;

src/logging/WriterBackend.h

@@ -5,12 +5,14 @@
 #ifndef LOGGING_WRITERBACKEND_H
 #define LOGGING_WRITERBACKEND_H
 
-#include "Manager.h"
-
 #include "threading/MsgThread.h"
 
+class RemoteSerializer;
+
 namespace logging  {
 
+class WriterFrontend;
+
 /**
  * Base class for writer implementation. When the logging::Manager creates a
  * new logging filter, it instantiates a WriterFrontend. That then in turn
@@ -41,21 +43,39 @@ public:
 	 */
 	virtual ~WriterBackend();
 
+	/**
+	 * A struct passing information to the writer at initialization time.
+	 */
+	struct WriterInfo
+		{
+		/**
+		 * A string left to the interpretation of the writer
+		 * implementation; it corresponds to the value configured on
+		 * the script-level for the logging filter.
+		 */
+		string path;
+
+		private:
+		friend class ::RemoteSerializer;
+
+		// Note, these need to be adapted when changing the struct's
+		// fields. They serialize/deserialize the struct.
+		bool Read(SerializationFormat* fmt);
+		bool Write(SerializationFormat* fmt) const;
+		};
+
 	/**
 	 * One-time initialization of the writer to define the logged fields.
 	 *
-	 * @param path A string left to the interpretation of the writer
+	 * @param info Meta information for the writer. 
-	 * implementation; it corresponds to the value configured on the
+	 * @param num_fields 
-	 * script-level for the logging filter.
-	 *
-	 * @param num_fields The number of log fields for the stream.
 	 *
 	 * @param fields An array of size \a num_fields with the log fields.
 	 * The methods takes ownership of the array.
 	 *
 	 * @return False if an error occured.
 	 */
-	bool Init(string path, int num_fields, const threading::Field* const*  fields);
+	bool Init(const WriterInfo& info, int num_fields, const threading::Field* const* fields);
 
 	/**
 	 * Writes one log entry.
@@ -108,9 +128,9 @@ public:
 	void DisableFrontend();
 
 	/**
-	 * Returns the log path as passed into the constructor.
+	 * Returns the additional writer information into the constructor.
 	 */
-	const string Path() const	{ return path; }
+	const WriterInfo& Info() const	{ return info; }
 
 	/**
 	 * Returns the number of log fields as passed into the constructor.
@@ -185,7 +205,7 @@ protected:
 	 * disabled and eventually deleted. When returning false, an
 	 * implementation should also call Error() to indicate what happened.
 	 */
-	virtual bool DoInit(string path, int num_fields,
+	virtual bool DoInit(const WriterInfo& info, int num_fields,
 			    const threading::Field* const*  fields) = 0;
 
 	/**
@@ -299,7 +319,7 @@ private:
 	// this class, it's running in a different thread!
 	WriterFrontend* frontend;
 
-	string path;	// Log path.
+	WriterInfo info;	// Meta information as passed to Init().
 	int num_fields;	// Number of log fields.
 	const threading::Field* const*  fields;	// Log fields.
 	bool buffering;	// True if buffering is enabled.

src/logging/WriterFrontend.cc

@@ -2,6 +2,7 @@
 #include "Net.h"
 #include "threading/SerialTypes.h"
 
+#include "Manager.h"
 #include "WriterFrontend.h"
 #include "WriterBackend.h"
 
@@ -15,14 +16,14 @@ namespace logging  {
 class InitMessage : public threading::InputMessage<WriterBackend>
 {
 public:
-	InitMessage(WriterBackend* backend, const string path, const int num_fields, const Field* const* fields)
+	InitMessage(WriterBackend* backend, const WriterBackend::WriterInfo& info, const int num_fields, const Field* const* fields)
 		: threading::InputMessage<WriterBackend>("Init", backend),
-		path(path), num_fields(num_fields), fields(fields) { }
+		info(info), num_fields(num_fields), fields(fields) { }
 
-	virtual bool Process() { return Object()->Init(path, num_fields, fields); }
+	virtual bool Process() { return Object()->Init(info, num_fields, fields); }
 
 private:
-	const string path;
+	WriterBackend::WriterInfo info;
 	const int num_fields;
 	const Field * const* fields;
 };
@@ -134,10 +135,10 @@ WriterFrontend::~WriterFrontend()
 
 string WriterFrontend::Name() const
 	{
-	if ( path.size() )
+	if ( info.path.size() )
 		return ty_name;
 
-	return ty_name + "/" + path;
+	return ty_name + "/" + info.path;
 	}
 
 void WriterFrontend::Stop()
@@ -149,7 +150,7 @@ void WriterFrontend::Stop()
 		backend->Stop();
 	}
 
-void WriterFrontend::Init(string arg_path, int arg_num_fields, const Field* const * arg_fields)
+void WriterFrontend::Init(const WriterBackend::WriterInfo& arg_info, int arg_num_fields, const Field* const * arg_fields)
 	{
 	if ( disabled )
 		return;
@@ -157,19 +158,19 @@ void WriterFrontend::Init(string arg_path, int arg_num_fields, const Field* cons
 	if ( initialized )
 		reporter->InternalError("writer initialize twice");
 
-	path = arg_path;
+	info = arg_info;
 	num_fields = arg_num_fields;
 	fields = arg_fields;
 
 	initialized = true;
 
 	if ( backend )
-		backend->SendIn(new InitMessage(backend, arg_path, arg_num_fields, arg_fields));
+		backend->SendIn(new InitMessage(backend, arg_info, arg_num_fields, arg_fields));
 
 	if ( remote )
 		remote_serializer->SendLogCreateWriter(stream,
 						       writer,
-						       arg_path,
+						       arg_info,
 						       arg_num_fields,
 						       arg_fields);
 
@@ -183,7 +184,7 @@ void WriterFrontend::Write(int num_fields, Value** vals)
 	if ( remote )
 		remote_serializer->SendLogWrite(stream,
 						writer,
-						path,
+						info.path,
 						num_fields,
 						vals);
 

src/logging/WriterFrontend.h

@@ -3,13 +3,13 @@
 #ifndef LOGGING_WRITERFRONTEND_H
 #define LOGGING_WRITERFRONTEND_H
 
-#include "Manager.h"
+#include "WriterBackend.h"
 
 #include "threading/MsgThread.h"
 
 namespace logging  {
 
-class WriterBackend;
+class Manager;
 
 /**
  * Bridge class between the logging::Manager and backend writer threads. The
@@ -68,7 +68,7 @@ public:
 	 *
 	 * This method must only be called from the main thread.
 	 */
-	void Init(string path, int num_fields, const threading::Field* const*  fields);
+	void Init(const WriterBackend::WriterInfo& info, int num_fields, const threading::Field* const*  fields);
 
 	/**
 	 * Write out a record.
@@ -169,9 +169,9 @@ public:
 	bool Disabled()	{ return disabled; }
 
 	/**
-	 * Returns the log path as passed into the constructor.
+	 * Returns the additional writer information as passed into the constructor.
 	 */
-	const string Path() const	{ return path; }
+	const WriterBackend::WriterInfo& Info() const	{ return info; }
 
 	/**
 	 * Returns the number of log fields as passed into the constructor.
@@ -207,7 +207,7 @@ protected:
 	bool remote;	// True if loggin remotely.
 
 	string ty_name;	// Name of the backend type. Set by the manager.
-	string path;	// The log path.
+	WriterBackend::WriterInfo info;	// The writer information.
 	int num_fields;	// The number of log fields.
 	const threading::Field* const*  fields;	// The log fields.
 

src/logging/writers/Ascii.cc

@@ -69,8 +69,10 @@ bool Ascii::WriteHeaderField(const string& key, const string& val)
 	return (fwrite(str.c_str(), str.length(), 1, file) == 1);
 	}
 
-bool Ascii::DoInit(string path, int num_fields, const Field* const * fields)
+bool Ascii::DoInit(const WriterInfo& info, int num_fields, const Field* const * fields)
 	{
+	string path = info.path;
+
 	if ( output_to_stdout )
 		path = "/dev/stdout";
 
@@ -290,7 +292,7 @@ bool Ascii::DoWrite(int num_fields, const Field* const * fields,
 			     Value** vals)
 	{
 	if ( ! file )
-		DoInit(Path(), NumFields(), Fields());
+		DoInit(Info(), NumFields(), Fields());
 
 	desc.Clear();
 
@@ -320,7 +322,7 @@ bool Ascii::DoWrite(int num_fields, const Field* const * fields,
 bool Ascii::DoRotate(string rotated_path, double open, double close, bool terminating)
 	{
 	// Don't rotate special files or if there's not one currently open.
-	if ( ! file || IsSpecial(Path()) )
+	if ( ! file || IsSpecial(Info().path) )
 		return true;
 
 	fclose(file);

src/logging/writers/Ascii.h

@@ -19,7 +19,7 @@ public:
 	static string LogExt();
 
 protected:
-	virtual bool DoInit(string path, int num_fields,
+	virtual bool DoInit(const WriterInfo& info, int num_fields,
 			    const threading::Field* const* fields);
 	virtual bool DoWrite(int num_fields, const threading::Field* const* fields,
 			     threading::Value** vals);

src/logging/writers/DataSeries.cc

@@ -263,7 +263,7 @@ bool DataSeries::OpenLog(string path)
 	return true;
 	}
 
-bool DataSeries::DoInit(string path, int num_fields, const threading::Field* const * fields)
+bool DataSeries::DoInit(const WriterInfo& info, int num_fields, const threading::Field* const * fields)
 	{
 	// We first construct an XML schema thing (and, if ds_dump_schema is
 	// set, dump it to path + ".ds.xml").  Assuming that goes well, we
@@ -298,11 +298,11 @@ bool DataSeries::DoInit(string path, int num_fields, const threading::Field* con
 		schema_list.push_back(val);
 		}
 
-	string schema = BuildDSSchemaFromFieldTypes(schema_list, path);
+	string schema = BuildDSSchemaFromFieldTypes(schema_list, info.path);
 
 	if( ds_dump_schema )
 		{
-		FILE* pFile = fopen ( string(path + ".ds.xml").c_str() , "wb" );
+		FILE* pFile = fopen ( string(info.path + ".ds.xml").c_str() , "wb" );
 
 		if( pFile )
 			{
@@ -340,7 +340,7 @@ bool DataSeries::DoInit(string path, int num_fields, const threading::Field* con
         log_type = log_types.registerTypePtr(schema);
 	log_series.setType(log_type);
 
-	return OpenLog(path);
+	return OpenLog(info.path);
 	}
 
 bool DataSeries::DoFlush()
@@ -401,7 +401,7 @@ bool DataSeries::DoRotate(string rotated_path, double open, double close, bool t
 	// size will be (much) larger.
 	CloseLog();
 
-	string dsname = Path() + ".ds";
+	string dsname = Info().path + ".ds";
 	string nname = rotated_path + ".ds";
 	rename(dsname.c_str(), nname.c_str());
 
@@ -411,7 +411,7 @@ bool DataSeries::DoRotate(string rotated_path, double open, double close, bool t
 		return false;
 		}
 
-	return OpenLog(Path());
+	return OpenLog(Info().path);
 }
 
 bool DataSeries::DoSetBuf(bool enabled)

src/logging/writers/DataSeries.h

@@ -26,7 +26,7 @@ public:
 protected:
 	// Overidden from WriterBackend.
 
-	virtual bool DoInit(string path, int num_fields,
+	virtual bool DoInit(const WriterInfo& info, int num_fields,
 			    const threading::Field* const * fields);
 
 	virtual bool DoWrite(int num_fields, const threading::Field* const* fields,

src/logging/writers/None.cc

@@ -6,9 +6,9 @@ using namespace writer;
 
 bool None::DoRotate(string rotated_path, double open, double close, bool terminating)
 	{
-	if ( ! FinishedRotation(string("/dev/null"), Path(), open, close, terminating))
+	if ( ! FinishedRotation(string("/dev/null"), Info().path, open, close, terminating))
 		{
-		Error(Fmt("error rotating %s", Path().c_str()));
+		Error(Fmt("error rotating %s", Info().path.c_str()));
 		return false;
 		}
 

src/logging/writers/None.h

@@ -18,7 +18,7 @@ public:
 		{ return new None(frontend); }
 
 protected:
-	virtual bool DoInit(string path, int num_fields,
+	virtual bool DoInit(const WriterInfo& info, int num_fields,
 			    const threading::Field* const * fields)	{ return true; }
 
 	virtual bool DoWrite(int num_fields, const threading::Field* const* fields,