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 unless DontCreateOnDemand
  92     // was called
  93   static wxConfigBase *Get() { if ( !ms_pConfig ) Create(); return ms_pConfig; }
  94     // create a new config object: this function will create the "best"
  95     // implementation of wxConfig available for the current platform, see
  96     // comments near definition wxCONFIG_WIN32_NATIVE for details. It returns
  97     // the created object and also sets it as ms_pConfig.
  98   static wxConfigBase *Create();
  99     // should Get() try to create a new log object if the current one is NULL?
 100   static void DontCreateOnDemand() { ms_bAutoCreate = FALSE; }
 101
 102   // ctor & virtual dtor
 103     // environment variable expansion is on by default
 104   wxConfigBase() { m_bExpandEnvVars = TRUE; }
 105     // empty but ensures that dtor of all derived classes is virtual
 106   virtual ~wxConfigBase() { }
 107
 108   // path management
 109     // set current path: if the first character is '/', it's the absolute path,
 110     // otherwise it's a relative path. '..' is supported. If the strPath
 111     // doesn't exist it is created.
 112   virtual void SetPath(const wxString& strPath) = 0;
 113     // retrieve the current path (always as absolute path)
 114   virtual const wxString& GetPath() const = 0;
 115
 116   // enumeration: all functions here return false when there are no more items.
 117   // you must pass the same lIndex to GetNext and GetFirst (don't modify it)
 118     // enumerate subgroups
 119   virtual bool GetFirstGroup(wxString& str, long& lIndex) const = 0;
 120   virtual bool GetNextGroup (wxString& str, long& lIndex) const = 0;
 121     // enumerate entries
 122   virtual bool GetFirstEntry(wxString& str, long& lIndex) const = 0;
 123   virtual bool GetNextEntry (wxString& str, long& lIndex) const = 0;
 124     // get number of entries/subgroups in the current group, with or without
 125     // it's subgroups
 126   virtual uint GetNumberOfEntries(bool bRecursive = FALSE) const = 0;
 127   virtual uint GetNumberOfGroups(bool bRecursive = FALSE) const = 0;
 128
 129   // tests of existence
 130     // returns TRUE if the group by this name exists
 131   virtual bool HasGroup(const wxString& strName) const = 0;
 132     // same as above, but for an entry
 133   virtual bool HasEntry(const wxString& strName) const = 0;
 134     // returns TRUE if either a group or an entry with a given name exist
 135   bool Exists(const wxString& strName) const
 136     { return HasGroup(strName) || HasEntry(strName); }
 137
 138   // key access: returns TRUE if value was really read, FALSE if default used
 139   // (and if the key is not found the default value is returned.)
 140     // read a string from the key
 141   virtual bool Read(wxString *pStr, const char *szKey,
 142                     const char *szDefault = NULL) const = 0;
 143     // another version using statis buffer - it means it will be overwritten
 144     // after each call to this function!
 145   virtual const char *Read(const char *szKey,
 146                            const char *szDefault = NULL) const;
 147     // the same for longs
 148   virtual long Read(const char *szKey, long lDefault) const
 149     { long l; Read(&l, szKey, lDefault); return l; }
 150     // and another version: returns true if default value is returned
 151   virtual bool Read(long *pl, const char *szKey, long lDefault = 0) const = 0;
 152
 153     // write the value (return true on success)
 154   virtual bool Write(const char *szKey, const char *szValue) = 0;
 155   virtual bool Write(const char *szKey, long lValue) = 0;
 156     // permanently writes all changes
 157   virtual bool Flush(bool bCurrentOnly = FALSE) = 0;
 158
 159   // delete entries/groups
 160     // deletes the specified entry and the group it belongs to if
 161     // it was the last key in it and the second parameter is true
 162   virtual bool DeleteEntry(const char *szKey,
 163                            bool bDeleteGroupIfEmpty = TRUE) = 0;
 164     // delete the group (with all subgroups)
 165   virtual bool DeleteGroup(const char *szKey) = 0;
 166     // delete the whole underlying object (disk file, registry key, ...)
 167     // primarly for use by desinstallation routine.
 168   virtual bool DeleteAll() = 0;
 169
 170   // options
 171     // we can automatically expand environment variables in the config entries
 172     // (this option is on by default, you can turn it on/off at any time)
 173   bool IsExpandingEnvVars() const { return m_bExpandEnvVars; }
 174   void SetExpandEnvVars(bool bDoIt = TRUE) { m_bExpandEnvVars = bDoIt; }
 175     // does expansion only if needed
 176   wxString ExpandEnvVars(const wxString& str) const
 177     {
 178         wxString tmp; // Required for BC++
 179         if (IsExpandingEnvVars())
 180             tmp = wxExpandEnvVars(str);
 181         else
 182             tmp = str;
 183         return tmp;
 184     }
 185
 186 protected:
 187   static bool IsImmutable(const char *szKey)
 188     { return *szKey == wxCONFIG_IMMUTABLE_PREFIX; }
 189
 190   // a handy little class which changes current path to the path of given entry
 191   // and restores it in dtor: so if you declare a local variable of this type,
 192   // you work in the entry directory and the path is automatically restored
 193   // when the function returns
 194   class PathChanger
 195   {
 196   public:
 197     // ctor/dtor do path changing/restorin
 198     PathChanger(const wxConfigBase *pContainer, const wxString& strEntry);
 199    ~PathChanger();
 200
 201     // get the key name
 202     const wxString& Name() const { return m_strName; }
 203
 204   private:
 205     wxConfigBase *m_pContainer;   // object we live in
 206     wxString      m_strName,      // name of entry (i.e. name only)
 207                   m_strOldPath;   // saved path
 208     bool          m_bChanged;     // was the path changed?
 209   };
 210
 211 private:
 212   // are we doing automatic environment variable expansion?
 213   bool m_bExpandEnvVars;
 214
 215   // static variables
 216   static wxConfigBase *ms_pConfig;
 217   static bool          ms_bAutoCreate;
 218 };
 219
 220 // ----------------------------------------------------------------------------
 221 // the native wxConfigBase implementation
 222 // ----------------------------------------------------------------------------
 223
 224 // under Windows we prefer to use the native implementation
 225 #if defined(__WXMSW__) && wxCONFIG_WIN32_NATIVE
 226   #ifdef __WIN32__
 227     #define wxConfig  wxRegConfig
 228   #else  //WIN16
 229     #define wxConfig  wxIniConfig
 230   #endif
 231 #else // either we're under Unix or wish to use files even under Windows
 232   #define wxConfig  wxFileConfig
 233 #endif
 234
 235 #endif  //_wxCONFIG_H
 236