ACE/ace/Configuration_Import_Export.h

   1 /* -*- C++ -*- */
   2
   3 //=============================================================================
   4 /**
   5  * @file Configuration_Import_Export.h
   6  *
   7  * @author Jerry D. Odenwelder Jr. <jerry.o@mindspring.com>
   8  *         Chris Hafey <chris@stentorsoft.com>
   9  *
  10  * Classes defined in this file provide the ability to import and export
  11  * ACE Configuration objects to/from disk files.  The base class
  12  * ACE_Config_ImpExp_Base provides the common functionality and the derived
  13  * classes implement the import/export functionality for the specific format.
  14  *
  15  * @todo
  16  *  - Add locking for thread safety.
  17  *  - Provide ability to read file in one format and write in another.
  18  *  - See todo's in each class
  19  */
  20 //=============================================================================
  21
  22 #ifndef ACE_CONFIGURATION_IMPORT_EXPORT_H
  23 #define ACE_CONFIGURATION_IMPORT_EXPORT_H
  24 #include /**/ "ace/pre.h"
  25
  26 #include "ace/Configuration.h"
  27 #include "ace/SString.h"
  28
  29 #if !defined (ACE_LACKS_PRAGMA_ONCE)
  30 # pragma once
  31 #endif /* ACE_LACKS_PRAGMA_ONCE */
  32
  33 ACE_BEGIN_VERSIONED_NAMESPACE_DECL
  34
  35 /**
  36  * @class ACE_Config_ImpExp_Base
  37  *
  38  * @brief Base class for file import/export configuration.
  39  *
  40  * This class provides base functionality for configuration objects
  41  * that are persisted in files.  It takes an ACE_Configuration
  42  * object that it populates with the data read.
  43  */
  44 class ACE_Export ACE_Config_ImpExp_Base
  45 {
  46 public:
  47   /// Constructor taking the ACE_Configuration to import/export to
  48   ACE_Config_ImpExp_Base (ACE_Configuration& config);
  49
  50   /**
  51    * Destructor
  52    */
  53   virtual ~ACE_Config_ImpExp_Base () = default;
  54
  55    /**
  56    * Imports the configuration database from @a filename.
  57    * No existing data is removed.
  58    */
  59   virtual int import_config (const ACE_TCHAR* filename) = 0;
  60
  61   /**
  62    * This method exports the entire configuration database to @a filename.
  63    * Once the file is opened this method calls 'export_section' passing
  64    * the root section.
  65    */
  66   virtual int export_config (const ACE_TCHAR* filename) = 0;
  67
  68 protected:
  69   ACE_Configuration &config_;
  70
  71 private:
  72   ACE_Config_ImpExp_Base (const ACE_Config_ImpExp_Base&) = delete;
  73   ACE_Config_ImpExp_Base& operator= (const ACE_Config_ImpExp_Base&) = delete;
  74 };
  75
  76 /**
  77  * @class ACE_Registry_ImpExp
  78  *
  79  * @brief Configuration object that imports/exports data to a file formatted
  80  *        using the Win32 Registry file export format.  This format looks like
  81  *        [Section]
  82  *        "key"="String Data"
  83  *        "key"=dword: numeric data in hexadecimal format
  84  *        "key"=hex: binary data
  85  *
  86  * @todo
  87  *  - Add dynamic buffer when importing.  currently it will not allow
  88  *    importing of values greater than a fixed amount (4096 bytes)
  89  */
  90 class ACE_Export ACE_Registry_ImpExp : public ACE_Config_ImpExp_Base
  91 {
  92 public:
  93   /// Construction
  94   ACE_Registry_ImpExp (ACE_Configuration&);
  95
  96   /// Destruction.
  97   virtual ~ACE_Registry_ImpExp () = default;
  98
  99   /**
 100    * Imports the configuration database from @a filename.
 101    * No existing data is removed.
 102    */
 103   virtual int import_config (const ACE_TCHAR* filename);
 104
 105   /**
 106    * This method exports the entire configuration database to @a filename.
 107    * Once the file is opened this method calls export_section() passing
 108    * the root section.
 109    */
 110   virtual int export_config (const ACE_TCHAR* filename);
 111
 112 private:
 113   int export_section (const ACE_Configuration_Section_Key& section,
 114                       const ACE_TString& path,
 115                       FILE* out);
 116
 117   int process_previous_line_format (ACE_TCHAR* buffer,
 118                                     ACE_Configuration_Section_Key& section);
 119
 120   ACE_Registry_ImpExp (const ACE_Registry_ImpExp&) = delete;
 121   ACE_Registry_ImpExp& operator= (const ACE_Registry_ImpExp&) = delete;
 122 };
 123
 124 /**
 125  * @class ACE_Ini_ImpExp
 126  *
 127  * @brief Imports the configuration database from filename as strings.
 128  *        Allows non-typed values. (no #, dword: hex:, etc. prefixes) and
 129  *        skips whitespace (tabs and spaces) as in standard .ini and .conf
 130  *        files. Values (to right of equal sign) can be double quote
 131  *        delimited to embed tabs and spaces in the string.
 132  *        Caller must convert string to type.
 133  *
 134  *        This method allows for lines in the .ini or .conf file like this:
 135  *
 136  *        TimeToLive     =    100
 137  *        Delay          =    FALSE
 138  *        Flags          =    FF34
 139  *        Heading        =    "ACE - Adaptive Communication Environment"
 140  *
 141  * (note leading whitespace (tabs) in examples below)
 142  *
 143  *        SeekIndex  =  14
 144  *        TraceLevel = 6      # Can comment lines like this
 145  *              Justification = left_justified
 146  *
 147  *        The caller can then retrieve the string with the regular
 148  *        get_string_value() function and convert the string to the
 149  *        desired data type.
 150  *
 151  * @todo
 152  *  - Strings with embedded newlines cause the import to fail
 153  *  - Strings with embedded quotes " cause the import to fail
 154  *  - Importing/exporting for values in the root section does not work
 155  *  - Add dynamic buffer when importing.  currently it will not allow
 156  *    importing of values greater than a fixed amount (4096 bytes)
 157 */
 158 class ACE_Export ACE_Ini_ImpExp  : public ACE_Config_ImpExp_Base
 159 {
 160 public:
 161   /**
 162    * Construction
 163    */
 164   ACE_Ini_ImpExp (ACE_Configuration&);
 165
 166   /**
 167    * Destructor
 168    */
 169   virtual ~ACE_Ini_ImpExp () = default;
 170
 171   /**
 172    * Imports the configuration database from @a filename.
 173    * No existing data is removed.
 174    */
 175   virtual int import_config (const ACE_TCHAR* filename);
 176
 177   /**
 178    * This method exports the entire configuration database to @a filename.
 179    * Once the file is opened this method calls export_section() passing
 180    * the root section.
 181    */
 182   virtual int export_config (const ACE_TCHAR* filename);
 183
 184 private:
 185   /**
 186    * Method provided by derived classes in order to write one section
 187    * to the file specified.  Called by export_config() when exporting
 188    * the entire configuration object.
 189    */
 190   int export_section (const ACE_Configuration_Section_Key& section,
 191                       const ACE_TString& path,
 192                       FILE* out);
 193
 194   /**
 195    * Method to squish leading and trailing whitespaces in a string.
 196    * Whitespace is defined as: spaces (' '), tabs ('\\t') or cr/lf.
 197    * Returns a pointer to the first non-whitespace character in the
 198    * buffer provided, or a pointer to the terminating null if the string
 199    * is all whitespace. The terminating null is moved forward to the
 200    * first character past the last non-whitespace.
 201    */
 202   ACE_TCHAR *squish (ACE_TCHAR *src);
 203
 204   ACE_Ini_ImpExp (const ACE_Ini_ImpExp&) = delete;
 205   ACE_Ini_ImpExp& operator= (const ACE_Ini_ImpExp&) = delete;
 206 };
 207
 208 ACE_END_VERSIONED_NAMESPACE_DECL
 209
 210 #include /**/ "ace/post.h"
 211 #endif /* ACE_CONFIGURATION_IMPORT_EXPORT_H */