xref: /haiku/headers/private/shared/SettingsHandler.h (revision 02354704729d38c3b078c696adc1bbbd33cbcf72)
1 /*
2 Open Tracker License
3 
4 Terms and Conditions
5 
6 Copyright (c) 1991-2000, Be Incorporated. All rights reserved.
7 
8 Permission is hereby granted, free of charge, to any person obtaining a copy of
9 this software and associated documentation files (the "Software"), to deal in
10 the Software without restriction, including without limitation the rights to
11 use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
12 of the Software, and to permit persons to whom the Software is furnished to do
13 so, subject to the following conditions:
14 
15 The above copyright notice and this permission notice applies to all licensees
16 and shall be included in all copies or substantial portions of the Software.
17 
18 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF TITLE, MERCHANTABILITY,
20 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
21 BE INCORPORATED BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
22 AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF, OR IN CONNECTION
23 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
24 
25 Except as contained in this notice, the name of Be Incorporated shall not be
26 used in advertising or otherwise to promote the sale, use or other dealings in
27 this Software without prior written authorization from Be Incorporated.
28 
29 Tracker(TM), Be(R), BeOS(R), and BeIA(TM) are trademarks or registered trademarks
30 of Be Incorporated in the United States and other countries. Other brand product
31 names are registered trademarks or trademarks of their respective holders.
32 All rights reserved.
33 */
34 #ifndef _SETTINGS_FILE_H
35 #define _SETTINGS_FILE_H
36 
37 
38 #include <stdarg.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 
43 #include <SupportDefs.h>
44 
45 
46 class BFile;
47 class BDirectory;
48 class BRect;
49 
50 namespace BPrivate {
51 
52 class Settings;
53 
54 typedef const char* (*ArgvHandler)(int argc, const char* const *argv,
55 	void* params);
56 	// return 0 or error string if parsing failed
57 
58 const int32 kBufferSize = 1024;
59 
60 
61 class ArgvParser {
62 	// this class opens a text file and passes the context in argv
63 	// format to a specified handler
64 public:
65 	static status_t EachArgv(const char* name,
66 		ArgvHandler argvHandlerFunc, void* passThru);
67 
68 private:
69 	ArgvParser(const char* name);
70 	~ArgvParser();
71 
72 	status_t EachArgvPrivate(const char* name,
73 		ArgvHandler argvHandlerFunc, void* passThru);
74 	int GetCh();
75 
76 	status_t SendArgv(ArgvHandler argvHandlerFunc, void* passThru);
77 		// done with a whole line of argv, send it off and get ready
78 		// to build a new one
79 
80 	void NextArgv();
81 		// done with current string, get ready to start building next
82 	void NextArgvIfNotEmpty();
83 		// as above, don't commint current string if empty
84 
85 	void MakeArgvEmpty();
86 
87 	FILE* fFile;
88 	char* fBuffer;
89 	int32 fPos;
90 
91 	int fArgc;
92 	char** fCurrentArgv;
93 
94 	int32 fCurrentArgsPos;
95 	char fCurrentArgs[1024];
96 
97 	bool fSawBackslash;
98 	bool fEatComment;
99 	bool fInDoubleQuote;
100 	bool fInSingleQuote;
101 
102 	int32 fLineNo;
103 	const char* fFileName;
104 };
105 
106 
107 class SettingsArgvDispatcher {
108 	// base class for a single setting item
109 public:
110 	SettingsArgvDispatcher(const char* name);
111 	virtual ~SettingsArgvDispatcher() {};
112 
113 	void SaveSettings(Settings* settings, bool onlyIfNonDefault);
114 
115 	const char* Name() const { return fName; }
116 		// name as it appears in the settings file
117 
118 	virtual const char* Handle(const char* const *argv) = 0;
119 		// override this adding an argv parser that reads in the
120 		// values in argv format for this setting
121 		// return a pointer to an error message or null if parsed OK
122 
123 	// some handy reader/writer calls
124 	bool HandleRectValue(BRect&, const char* const *argv,
125 		bool printError = true);
126 	void WriteRectValue(Settings*, BRect);
127 
128 protected:
129 	virtual void SaveSettingValue(Settings* settings) = 0;
130 		// override this to save the current value of this setting in a
131 		// text format
132 
133 	virtual bool NeedsSaving() const { return true; }
134 		// override to return false if current value is equal to the default
135 		// and does not need saving
136 
137 private:
138 	const char* fName;
139 };
140 
141 
142 class Settings {
143 	// this class is a list of all the settings handlers, reads and
144 	// saves the settings file
145 public:
146 	Settings(const char* filename, const char* settingsDirName);
147 	~Settings();
148 	void TryReadingSettings();
149 	void SaveSettings(bool onlyIfNonDefault = true);
150 
151 	bool Add(SettingsArgvDispatcher*);
152 		// return false if argv dispatcher with the same name already
153 		// registered
154 
155 	void Write(const char* format, ...);
156 	void VSWrite(const char*, va_list);
157 
158 private:
159 	void MakeSettingsDirectory(BDirectory*);
160 
161 	SettingsArgvDispatcher* Find(const char*);
162 	static const char* ParseUserSettings(int, const char* const *argv, void*);
163 	void SaveCurrentSettings(bool onlyIfNonDefault);
164 
165 	const char* fFileName;
166 	const char* fSettingsDir;
167 		// currently unused
168 	SettingsArgvDispatcher** fList;
169 	int32 fCount;
170 	int32 fListSize;
171 	BFile* fCurrentSettings;
172 };
173 
174 }	// namespace BPrivate
175 
176 using namespace BPrivate;
177 
178 
179 #endif	// _SETTINGS_FILE_H
180