ACE/ace/Svc_Conf_Param.h

   1 // -*- C++ -*-
   2
   3 //=============================================================================
   4 /**
   5  *  @file    Svc_Conf_Param.h
   6  *
   7  *  @author Iliyan Jeliazkov <iliyan@ociweb.com>
   8  *  @author Based on code originally found in Svc_Conf.h by Doug
   9             Schmidt and Ossama Othman.
  10  */
  11 //=============================================================================
  12
  13
  14 #ifndef ACE_SVC_CONF_PARAM_H
  15 #define ACE_SVC_CONF_PARAM_H
  16
  17 #include /**/ "ace/pre.h"
  18
  19 // Globally visible macros, type decls, and extern var decls for
  20 // Service Configurator utility.
  21
  22 #include "ace/Obstack.h"
  23
  24 #if !defined (ACE_LACKS_PRAGMA_ONCE)
  25 # pragma once
  26 #endif /* ACE_LACKS_PRAGMA_ONCE */
  27
  28 ACE_BEGIN_VERSIONED_NAMESPACE_DECL
  29
  30 // Forward declarations.
  31 struct ace_yy_buffer_state;
  32 class ACE_Service_Gestalt;
  33
  34 extern void ace_yy_delete_buffer (ace_yy_buffer_state *buffer);
  35
  36 /**
  37  * @class ACE_Svc_Conf_Param
  38  *
  39  * @brief An instance of this object will be passed down to the
  40  *        yyparse() and yylex() functions.
  41  *
  42  * This is intended for internal use within ACE service configuration
  43  * framework only.
  44  *
  45  * This class retains the state for a given parse/scan.  It primarily
  46  * makes it possible to hold the static object lock in the scanner
  47  * for as short a period of time as possible.  The resulting finer
  48  * grained locking prevents deadlocks from occurring when scanning a
  49  * `svc.conf' file and activating an ACE_Task, for example, as a
  50  * result of processing the directives in that file.
  51  */
  52 class ACE_Svc_Conf_Param
  53 {
  54 public:
  55   enum SVC_CONF_PARAM_TYPE
  56     {
  57       /// The lexer will scan a file containing one or more directives.
  58       SVC_CONF_FILE,
  59
  60       /// The lexer will scan a string containing a directive.
  61       SVC_CONF_DIRECTIVE
  62     };
  63
  64   /// Constructor
  65   ACE_Svc_Conf_Param (ACE_Service_Gestalt* config, FILE *file)
  66     : type (SVC_CONF_FILE),
  67       yyerrno (0),
  68       yylineno (1),
  69       buffer (0),
  70       obstack (),
  71       config (config)
  72   {
  73     source.file = file;
  74   }
  75
  76   /// Constructor
  77   ACE_Svc_Conf_Param (ACE_Service_Gestalt* config, const ACE_TCHAR *directive)
  78     : type (SVC_CONF_DIRECTIVE),
  79       yyerrno (0),
  80       yylineno (1),
  81       buffer (0),
  82       obstack (),
  83       config (config)
  84   {
  85     source.directive = directive;
  86   }
  87
  88   ~ACE_Svc_Conf_Param ()
  89   {
  90     ace_yy_delete_buffer (this->buffer);
  91   }
  92
  93 public:
  94   union
  95   {
  96     /// FILE stream from which directives will be scanned and parsed.
  97     FILE *file;
  98
  99     /// String containing directive that will be scanned and parsed.
 100     const ACE_TCHAR *directive;
 101   } source;
 102
 103   /// Discriminant use to determine which union member to use.
 104   SVC_CONF_PARAM_TYPE type;
 105
 106   /// Keeps track of the number of errors encountered so far.
 107   int yyerrno;
 108
 109   /// Keeps track of the current line number for error-handling routine.
 110   int yylineno;
 111
 112   /// Lexer buffer that corresponds to the current Service
 113   /// Configurator file/direct scan.
 114   ace_yy_buffer_state *buffer;
 115
 116   /// Obstack used for efficient memory allocation when
 117   /// parsing/scanning a service configurator directive.
 118   ACE_Obstack_T<ACE_TCHAR> obstack;
 119
 120   /// A reference to the configuration
 121   ACE_Service_Gestalt *config;
 122 };
 123
 124
 125 // Parameter that is passed down to the yyparse() function, and
 126 // eventually to yylex().
 127 #define YYPARSE_PARAM ace_svc_conf_parameter
 128
 129 #define YYLEX_PARAM YYPARSE_PARAM
 130
 131 #define ACE_SVC_CONF_PARAM (static_cast<ACE_Svc_Conf_Param *> (YYLEX_PARAM))
 132
 133 ACE_END_VERSIONED_NAMESPACE_DECL
 134
 135 #include /**/ "ace/post.h"
 136
 137 #endif /* ACE_SVC_CONF_PARAM_H */