Refactored formatters and updated the the writers a bit.

- Formatters have been abstracted similarly to readers and writers now.
 - The Ascii writer has a new option for writing out logs as JSON.
 - The Ascii writer now has all options availble as per-filter
   options as well as global.

src/threading/formatters/Ascii.h

@@ -0,0 +1,62 @@
+// See the file "COPYING" in the main distribution directory for copyright.
+
+#ifndef THREADING_FORMATTERS_ASCII_H
+#define THREADING_FORMATTERS_ASCII_H
+
+#include "../Formatter.h"
+
+namespace threading { namespace formatter {
+
+class Ascii : public Formatter {
+public:
+	/**
+	 * A struct to pass the necessary configuration values to the
+	 * Ascii module on initialization.
+	 */
+	struct SeparatorInfo
+		{
+		string separator;		// Separator between columns
+		string set_separator;	// Separator between set elements.
+		string unset_field;	// String marking an unset field.
+		string empty_field;	// String marking an empty (but set) field.
+
+		/**
+		 * Constructor that leaves separators etc unset to dummy
+		 * values. Useful if you use only methods that don't need any
+		 * of them, like StringToAddr, etc.
+		 */
+		SeparatorInfo();
+
+		/**
+		 * Constructor that defines all the configuration options.
+		 * Use if you need either ValToODesc or EntryToVal.
+		 */
+		SeparatorInfo(const string& separator, const string& set_separator, const string& unset_field, const string& empty_field);
+		};
+
+	/**
+	 * Constructor.
+	 *
+	 * @param t The thread that uses this class instance. The class uses
+	 * some of the thread's methods, e.g., for error reporting and
+	 * internal formatting.
+	 *
+	 * @param info SeparatorInfo structure defining the necessary
+	 * separators.
+	 */
+	Ascii(threading::MsgThread* t, const SeparatorInfo info);
+	virtual ~Ascii();
+
+	virtual bool Describe(ODesc* desc, threading::Value* val) const;
+	virtual bool Describe(ODesc* desc, threading::Value* val, const string& name) const;
+	virtual bool Describe(ODesc* desc, int num_fields, const threading::Field* const * fields,
+	                      threading::Value** vals) const;
+	virtual threading::Value* ParseValue(string s, string name, TypeTag type, TypeTag subtype = TYPE_ERROR) const;
+
+private:
+	SeparatorInfo separators;
+};
+
+}}
+
+#endif /* THREADING_FORMATTERS_ASCII_H */