include/wx/config.h

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        config.h
   3 // Purpose:     declaration of the base class of all config implementations
   4 //              (see also: fileconf.h and msw/regconf.h)
   5 // Author:      Karsten Ballüder & Vadim Zeitlin
   6 // Modified by:
   7 // Created:     07.04.98 (adapted from appconf.h)
   8 // RCS-ID:      $Id$
   9 // Copyright:   (c) 1997 Karsten Ballüder   Ballueder@usa.net
  10 //                       Vadim Zeitlin      <zeitlin@dptmaths.ens-cachan.fr>
  11 // Licence:     wxWindows license
  12 ///////////////////////////////////////////////////////////////////////////////
  13
  14 #ifndef   _wxCONFIG_H
  15 #define   _wxCONFIG_H
  16
  17 #ifdef __GNUG__
  18 #pragma interface "config.h"
  19 #endif
  20
  21 // ----------------------------------------------------------------------------
  22 // compile options
  23 // ----------------------------------------------------------------------------
  24
  25 // it won't compile without it anyhow
  26 #ifndef USE_WXCONFIG
  27   #error "Please define USE_WXCONFIG or remove config.cpp from your makefile"
  28 #endif // USE_WXCONFIG
  29
  30 // ----------------------------------------------------------------------------
  31 // constants
  32 // ----------------------------------------------------------------------------
  33
  34 /// shall we be case sensitive in parsing variable names?
  35 #ifndef wxCONFIG_CASE_SENSITIVE
  36   #define  wxCONFIG_CASE_SENSITIVE       FALSE
  37 #endif
  38
  39 /// separates group and entry names (probably shouldn't be changed)
  40 #ifndef wxCONFIG_PATH_SEPARATOR
  41   #define   wxCONFIG_PATH_SEPARATOR     '/'
  42 #endif
  43
  44 /// introduces immutable entries
  45 // (i.e. the ones which can't be changed from the local config file)
  46 #ifndef wxCONFIG_IMMUTABLE_PREFIX
  47   #define   wxCONFIG_IMMUTABLE_PREFIX   '!'
  48 #endif
  49
  50 /// should we use registry instead of configuration files under Win32?
  51 // (i.e. whether wxConfigBase::Create() will create a wxFileConfig (if it's
  52 //  FALSE) or wxRegConfig (if it's true and we're under Win32) or wxIniConfig
  53 //  (under Win16))
  54 #ifndef   wxCONFIG_WIN32_NATIVE
  55   #define wxCONFIG_WIN32_NATIVE          TRUE
  56 #endif
  57
  58 // ----------------------------------------------------------------------------
  59 // various helper global functions
  60 // ----------------------------------------------------------------------------
  61
  62 /*
  63   Replace environment variables ($SOMETHING) with their values. The format is
  64   $VARNAME or ${VARNAME} where VARNAME contains alphanumeric characters and
  65   '_' only. '$' must be escaped ('\$') in order to be taken literally.
  66  */
  67 extern wxString wxExpandEnvVars(const wxString &sz);
  68
  69 /*
  70   Split path into parts removing '..' in progress
  71  */
  72 extern void wxSplitPath(wxArrayString& aParts, const char *sz);
  73
  74 // ----------------------------------------------------------------------------
  75 // abstract base class wxConfigBase which defines the interface for derived
  76 // classes
  77 //
  78 // wxConfig organizes the items in a tree-like structure (modeled after the
  79 // Unix/Dos filesystem). There are groups (directories) and keys (files).
  80 // There is always one current group given by the current path.
  81 //
  82 // Keys are pairs "key_name = value" where value may be of string or integer
  83 // (long) type (@@@ doubles and other types such as wxDate coming soon).
  84 // ----------------------------------------------------------------------------
  85 class wxConfigBase
  86 {
  87 public:
  88   // static functions
  89     // sets the config object, returns the previous pointer
  90   static wxConfigBase *Set(wxConfigBase *pConfig);
  91     // get the config object, creates it on demand
  92   static wxConfigBase *Get() { if ( !ms_pConfig ) Create(); return ms_pConfig; }
  93     // create a new config object: this function will create the "best"
  94     // implementation of wxConfig available for the current platform, see
  95     // comments near definition wxCONFIG_WIN32_NATIVE for details. It returns
  96     // the created object and also sets it as ms_pConfig.
  97   static wxConfigBase *Create();
  98
  99   // ctor & virtual dtor
 100     // environment variable expansion is on by default
 101   wxConfigBase() { m_bExpandEnvVars = TRUE; }
 102     // empty but ensures that dtor of all derived classes is virtual
 103   virtual ~wxConfigBase() { }
 104
 105   // path management
 106     // set current path: if the first character is '/', it's the absolute path,
 107     // otherwise it's a relative path. '..' is supported. If the strPath
 108     // doesn't exist it is created.
 109   virtual void SetPath(const wxString& strPath) = 0;
 110     // retrieve the current path (always as absolute path)
 111   virtual const wxString& GetPath() const = 0;
 112
 113   // enumeration: all functions here return false when there are no more items.
 114   // you must pass the same lIndex to GetNext and GetFirst (don't modify it)
 115     // enumerate subgroups
 116   virtual bool GetFirstGroup(wxString& str, long& lIndex) const = 0;
 117   virtual bool GetNextGroup (wxString& str, long& lIndex) const = 0;
 118     // enumerate entries
 119   virtual bool GetFirstEntry(wxString& str, long& lIndex) const = 0;
 120   virtual bool GetNextEntry (wxString& str, long& lIndex) const = 0;
 121     // get number of entries/subgroups in the current group, with or without
 122     // it's subgroups
 123   virtual uint GetNumberOfEntries(bool bRecursive = FALSE) const = 0;
 124   virtual uint GetNumberOfGroups(bool bRecursive = FALSE) const = 0;
 125
 126   // tests of existence
 127     // returns TRUE if the group by this name exists
 128   virtual bool HasGroup(const wxString& strName) const = 0;
 129     // same as above, but for an entry
 130   virtual bool HasEntry(const wxString& strName) const = 0;
 131     // returns TRUE if either a group or an entry with a given name exist
 132   bool Exists(const wxString& strName) const
 133     { return HasGroup(strName) || HasEntry(strName); }
 134
 135   // key access: returns TRUE if value was really read, FALSE if default used
 136   // (and if the key is not found the default value is returned.)
 137     // read a string from the key
 138   virtual bool Read(wxString *pStr, const char *szKey,
 139                     const char *szDefault = NULL) const = 0;
 140     // another version using statis buffer - it means it will be overwritten
 141     // after each call to this function!
 142   virtual const char *Read(const char *szKey,
 143                            const char *szDefault = NULL) const;
 144     // the same for longs
 145   virtual long Read(const char *szKey, long lDefault) const
 146     { long l; Read(&l, szKey, lDefault); return l; }
 147     // and another version: returns true if default value is returned
 148   virtual bool Read(long *pl, const char *szKey, long lDefault = 0) const = 0;
 149
 150     // write the value (return true on success)
 151   virtual bool Write(const char *szKey, const char *szValue) = 0;
 152   virtual bool Write(const char *szKey, long lValue) = 0;
 153     // permanently writes all changes
 154   virtual bool Flush(bool bCurrentOnly = FALSE) = 0;
 155
 156   // delete entries/groups
 157     // deletes the specified entry and the group it belongs to if
 158     // it was the last key in it and the second parameter is true
 159   virtual bool DeleteEntry(const char *szKey,
 160                            bool bDeleteGroupIfEmpty = TRUE) = 0;
 161     // delete the group (with all subgroups)
 162   virtual bool DeleteGroup(const char *szKey) = 0;
 163     // delete the whole underlying object (disk file, registry key, ...)
 164     // primarly for use by desinstallation routine.
 165   virtual bool DeleteAll() = 0;
 166
 167   // options
 168     // we can automatically expand environment variables in the config entries
 169     // (this option is on by default, you can turn it on/off at any time)
 170   bool IsExpandingEnvVars() const { return m_bExpandEnvVars; }
 171   void SetExpandEnvVars(bool bDoIt = TRUE) { m_bExpandEnvVars = bDoIt; }
 172     // does expansion only if needed
 173   wxString ExpandEnvVars(const wxString& str) const
 174     {
 175         wxString tmp; // Required for BC++
 176         if (IsExpandingEnvVars())
 177             tmp = wxExpandEnvVars(str);
 178         else
 179             tmp = str;
 180         return tmp;
 181     }
 182
 183 protected:
 184   static bool IsImmutable(const char *szKey)
 185     { return *szKey == wxCONFIG_IMMUTABLE_PREFIX; }
 186
 187   // a handy little class which changes current path to the path of given entry
 188   // and restores it in dtor: so if you declare a local variable of this type,
 189   // you work in the entry directory and the path is automatically restored
 190   // when the function returns
 191   class PathChanger
 192   {
 193   public:
 194     // ctor/dtor do path changing/restorin
 195     PathChanger(const wxConfigBase *pContainer, const wxString& strEntry);
 196    ~PathChanger();
 197
 198     // get the key name
 199     const wxString& Name() const { return m_strName; }
 200
 201   private:
 202     wxConfigBase *m_pContainer;   // object we live in
 203     wxString      m_strName,      // name of entry (i.e. name only)
 204                   m_strOldPath;   // saved path
 205     bool          m_bChanged;     // was the path changed?
 206   };
 207
 208 private:
 209   // are we doing automatic environment variable expansion?
 210   bool m_bExpandEnvVars;
 211
 212   // static variables
 213   static wxConfigBase *ms_pConfig;
 214 };
 215
 216 // ----------------------------------------------------------------------------
 217 // the native wxConfigBase implementation
 218 // ----------------------------------------------------------------------------
 219
 220 // under Windows we prefer to use the native implementation
 221 #if defined(__WXMSW__) && wxCONFIG_WIN32_NATIVE
 222   #ifdef __WIN32__
 223     #define wxConfig  wxRegConfig
 224   #else  //WIN16
 225     #define wxConfig  wxIniConfig
 226   #endif
 227 #else // either we're under Unix or wish to use files even under Windows
 228   #define wxConfig  wxFileConfig
 229 #endif
 230
 231 #endif  //_wxCONFIG_H