haiku/headers/os/storage/Query.h

/*
 * Copyright 2002-2009, Haiku, Inc. All Rights Reserved.
 * Distributed under the terms of the MIT License.
 */
#ifndef _QUERY_H
#define _QUERY_H


#include <EntryList.h>
#include <Messenger.h>
#include <OS.h>

class BVolume;
struct entry_ref;


namespace BPrivate {
	namespace Storage {
		class QueryNode;
		class QueryStack;
		class QueryTree;
	};
};

typedef enum {
	B_INVALID_OP	= 0,
	B_EQ,
	B_GT,
	B_GE,
	B_LT,
	B_LE,
	B_NE,
	B_CONTAINS,
	B_BEGINS_WITH,
	B_ENDS_WITH,
	B_AND			= 0x101,
	B_OR,
	B_NOT,
	_B_RESERVED_OP_	= 0x100000
} query_op;


/*!
	\class BQuery
	\brief Represents a live or non-live file system query

	Provides an interface for creating file system queries. Implements
	the BEntryList for iterating through the found entries.

	\author <a href='mailto:bonefish@users.sf.net'>Ingo Weinhold</a>

	\version 0.0.0
*/
class BQuery : public BEntryList {
public:
							BQuery();
	virtual					~BQuery();

			status_t		Clear();

			status_t		PushAttr(const char* attrName);
			status_t		PushOp(query_op op);

			status_t		PushUInt32(uint32 value);
			status_t		PushInt32(int32 value);
			status_t		PushUInt64(uint64 value);
			status_t		PushInt64(int64 value);
			status_t		PushFloat(float value);
			status_t		PushDouble(double value);
			status_t		PushString(const char* value,
								bool caseInsensitive = false);
			status_t		PushDate(const char* date);

			status_t		SetVolume(const BVolume* volume);
			status_t		SetPredicate(const char* expression);
			status_t		SetTarget(BMessenger messenger);

			bool			IsLive() const;

			status_t		GetPredicate(char* buffer, size_t length);
			status_t		GetPredicate(BString* predicate);
			size_t			PredicateLength();

			dev_t			TargetDevice() const;

			status_t		Fetch();

	// BEntryList interface
	virtual	status_t		GetNextEntry(BEntry* entry, bool traverse = false);
	virtual	status_t		GetNextRef(entry_ref* ref);
	virtual	int32			GetNextDirents(struct dirent* buffer, size_t length,
								 int32 count = INT_MAX);
	virtual	status_t		Rewind();
	virtual	int32			CountEntries();

private:
			bool			_HasFetched() const;
			status_t		_PushNode(BPrivate::Storage::QueryNode* node,
								bool deleteOnError);
			status_t		_SetPredicate(const char* expression);
			status_t		_EvaluateStack();
			void			_ParseDates(BString& parsedPredicate);

	// FBC
	virtual	void			_QwertyQuery1();
	virtual	void			_QwertyQuery2();
	virtual	void			_QwertyQuery3();
	virtual	void			_QwertyQuery4();
	virtual	void			_QwertyQuery5();
	virtual	void			_QwertyQuery6();

private:
			BPrivate::Storage::QueryStack* fStack;
			char*			fPredicate;
			dev_t			fDevice;
			bool			fLive;
			port_id			fPort;
			long			fToken;
			int				fQueryFd;
			int32			_reservedData[4];
};

#endif	// _QUERY_H