os_win32/wmiquery.h

   1 /*
   2  * os_win32/wmiquery.h
   3  *
   4  * Home page of code is: http://smartmontools.sourceforge.net
   5  *
   6  * Copyright (C) 2011 Christian Franke <smartmontools-support@lists.sourceforge.net>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2, or (at your option)
  11  * any later version.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * (for example COPYING); If not, see <http://www.gnu.org/licenses/>.
  15  *
  16  */
  17
  18 #ifndef WMIQUERY_H
  19 #define WMIQUERY_H
  20
  21 #define WMIQUERY_H_CVSID "$Id: wmiquery.h 3243 2011-01-19 20:03:47Z chrfranke $"
  22
  23 #ifdef HAVE_WBEMCLI_H
  24 #include <wbemcli.h>
  25 #else
  26 #include "wbemcli_small.h"
  27 #endif
  28
  29 #include <string>
  30
  31 #if !defined(__GNUC__) && !defined(__attribute__)
  32 #define __attribute__(x)  /**/
  33 #endif
  34
  35 /////////////////////////////////////////////////////////////////////////////
  36 // com_bstr
  37
  38 /// Wrapper class for COM BSTR
  39 class com_bstr
  40 {
  41 public:
  42   /// Construct from string.
  43   com_bstr(const char * str);
  44
  45   /// Destructor frees BSTR.
  46   ~com_bstr()
  47     { SysFreeString(m_bstr); }
  48
  49   /// Implicit conversion to BSTR.
  50   operator BSTR()
  51     { return m_bstr; }
  52
  53   /// Convert BSTR back to std::string.
  54   static bool to_str(const BSTR & bstr, std::string & str);
  55
  56 private:
  57   BSTR m_bstr;
  58
  59   com_bstr(const com_bstr &);
  60   void operator=(const com_bstr &);
  61 };
  62
  63
  64 /////////////////////////////////////////////////////////////////////////////
  65 // com_intf_ptr
  66
  67 /// Wrapper class for COM Interface pointer
  68 template <class T>
  69 class com_intf_ptr
  70 {
  71 public:
  72   /// Construct empty object
  73   com_intf_ptr()
  74     : m_ptr(0) { }
  75
  76   /// Destructor releases the interface.
  77   ~com_intf_ptr()
  78     { reset(); }
  79
  80   /// Release interface and clear the pointer.
  81   void reset()
  82     {
  83       if (m_ptr) {
  84         m_ptr->Release(); m_ptr = 0;
  85       }
  86     }
  87
  88   /// Return the pointer.
  89   T * get()
  90     { return m_ptr; }
  91
  92   /// Pointer dereferencing.
  93   T * operator->()
  94     { return m_ptr; }
  95
  96   /// Return address of pointer for replacement.
  97   T * * replace()
  98     { reset(); return &m_ptr; }
  99
 100   /// For (ptr != 0) check.
 101   operator bool() const
 102     { return !!m_ptr; }
 103
 104   /// For (ptr == 0) check.
 105   bool operator!() const
 106     { return !m_ptr; }
 107
 108 private:
 109   T * m_ptr;
 110
 111   com_intf_ptr(const com_intf_ptr &);
 112   void operator=(const com_intf_ptr &);
 113 };
 114
 115
 116 /////////////////////////////////////////////////////////////////////////////
 117 // wbem_object
 118
 119 class wbem_enumerator;
 120
 121 /// Wrapper class for IWbemClassObject
 122 class wbem_object
 123 {
 124 public:
 125   /// Get string representation.
 126   std::string get_str(const char * name) /*const*/;
 127
 128 private:
 129   /// Contents is set by wbem_enumerator.
 130   friend class wbem_enumerator;
 131   com_intf_ptr<IWbemClassObject> m_intf;
 132 };
 133
 134
 135 /////////////////////////////////////////////////////////////////////////////
 136 // wbem_enumerator
 137
 138 class wbem_services;
 139
 140 /// Wrapper class for IEnumWbemClassObject
 141 class wbem_enumerator
 142 {
 143 public:
 144   /// Get next object, return false if none or error.
 145   bool next(wbem_object & obj);
 146
 147 private:
 148   /// Contents is set by wbem_services.
 149   friend class wbem_services;
 150   com_intf_ptr<IEnumWbemClassObject> m_intf;
 151 };
 152
 153
 154 /////////////////////////////////////////////////////////////////////////////
 155 // wbem_services
 156
 157 /// Wrapper class for IWbemServices
 158 class wbem_services
 159 {
 160 public:
 161   /// Connect to service, return false on error.
 162   bool connect();
 163
 164   /// Execute query, get result list.
 165   /// Return false on error.
 166   bool vquery(wbem_enumerator & result, const char * qstr, va_list args) /*const*/;
 167
 168   /// Execute query, get single result object.
 169   /// Return false on error or result size != 1.
 170   bool vquery1(wbem_object & obj, const char * qstr, va_list args) /*const*/;
 171
 172   /// Version of vquery() with printf() formatting.
 173   bool query(wbem_enumerator & result, const char * qstr, ...) /*const*/
 174        __attribute__ ((format (printf, 3, 4)));
 175
 176   /// Version of vquery1() with printf() formatting.
 177   bool query1(wbem_object & obj, const char * qstr, ...) /*const*/
 178        __attribute__ ((format (printf, 3, 4)));
 179
 180 private:
 181   com_intf_ptr<IWbemServices> m_intf;
 182 };
 183
 184 #endif // WMIQUERY_H