os_win32/wmiquery.h

   1 /*
   2  * os_win32/wmiquery.h
   3  *
   4  * Home page of code is: http://www.smartmontools.org
   5  *
   6  * Copyright (C) 2011-15 Christian Franke
   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 4152 2015-10-17 16:08:21Z 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 #ifndef __GNUC__
  32 #define __attribute_format_printf(x, y)  /**/
  33 #elif defined(__MINGW32__) && __USE_MINGW_ANSI_STDIO
  34 // Check format of __mingw_*printf() instead of MSVCRT.DLL:*printf()
  35 #define __attribute_format_printf(x, y)  __attribute__((format (gnu_printf, x, y)))
  36 #else
  37 #define __attribute_format_printf(x, y)  __attribute__((format (printf, x, y)))
  38 #endif
  39
  40 /////////////////////////////////////////////////////////////////////////////
  41 // com_bstr
  42
  43 /// Wrapper class for COM BSTR
  44 class com_bstr
  45 {
  46 public:
  47   /// Construct from string.
  48   explicit com_bstr(const char * str);
  49
  50   /// Destructor frees BSTR.
  51   ~com_bstr()
  52     { SysFreeString(m_bstr); }
  53
  54   /// Implicit conversion to BSTR.
  55   operator BSTR()
  56     { return m_bstr; }
  57
  58   /// Convert BSTR back to std::string.
  59   static bool to_str(const BSTR & bstr, std::string & str);
  60
  61 private:
  62   BSTR m_bstr;
  63
  64   com_bstr(const com_bstr &);
  65   void operator=(const com_bstr &);
  66 };
  67
  68
  69 /////////////////////////////////////////////////////////////////////////////
  70 // com_intf_ptr
  71
  72 /// Wrapper class for COM Interface pointer
  73 template <class T>
  74 class com_intf_ptr
  75 {
  76 public:
  77   /// Construct empty object
  78   com_intf_ptr()
  79     : m_ptr(0) { }
  80
  81   /// Destructor releases the interface.
  82   ~com_intf_ptr()
  83     { reset(); }
  84
  85   /// Release interface and clear the pointer.
  86   void reset()
  87     {
  88       if (m_ptr) {
  89         m_ptr->Release(); m_ptr = 0;
  90       }
  91     }
  92
  93   /// Return the pointer.
  94   T * get()
  95     { return m_ptr; }
  96
  97   /// Pointer dereferencing.
  98   T * operator->()
  99     { return m_ptr; }
 100
 101   /// Return address of pointer for replacement.
 102   T * * replace()
 103     { reset(); return &m_ptr; }
 104
 105   /// For (ptr != 0) check.
 106   operator bool() const
 107     { return !!m_ptr; }
 108
 109   /// For (ptr == 0) check.
 110   bool operator!() const
 111     { return !m_ptr; }
 112
 113 private:
 114   T * m_ptr;
 115
 116   com_intf_ptr(const com_intf_ptr &);
 117   void operator=(const com_intf_ptr &);
 118 };
 119
 120
 121 /////////////////////////////////////////////////////////////////////////////
 122 // wbem_object
 123
 124 class wbem_enumerator;
 125
 126 /// Wrapper class for IWbemClassObject
 127 class wbem_object
 128 {
 129 public:
 130   /// Get string representation.
 131   std::string get_str(const char * name) /*const*/;
 132
 133 private:
 134   /// Contents is set by wbem_enumerator.
 135   friend class wbem_enumerator;
 136   com_intf_ptr<IWbemClassObject> m_intf;
 137 };
 138
 139
 140 /////////////////////////////////////////////////////////////////////////////
 141 // wbem_enumerator
 142
 143 class wbem_services;
 144
 145 /// Wrapper class for IEnumWbemClassObject
 146 class wbem_enumerator
 147 {
 148 public:
 149   /// Get next object, return false if none or error.
 150   bool next(wbem_object & obj);
 151
 152 private:
 153   /// Contents is set by wbem_services.
 154   friend class wbem_services;
 155   com_intf_ptr<IEnumWbemClassObject> m_intf;
 156 };
 157
 158
 159 /////////////////////////////////////////////////////////////////////////////
 160 // wbem_services
 161
 162 /// Wrapper class for IWbemServices
 163 class wbem_services
 164 {
 165 public:
 166   /// Connect to service, return false on error.
 167   bool connect();
 168
 169   /// Execute query, get result list.
 170   /// Return false on error.
 171   bool vquery(wbem_enumerator & result, const char * qstr, va_list args) /*const*/;
 172
 173   /// Execute query, get single result object.
 174   /// Return false on error or result size != 1.
 175   bool vquery1(wbem_object & obj, const char * qstr, va_list args) /*const*/;
 176
 177   /// Version of vquery() with printf() formatting.
 178   bool query(wbem_enumerator & result, const char * qstr, ...) /*const*/
 179        __attribute_format_printf(3, 4);
 180
 181   /// Version of vquery1() with printf() formatting.
 182   bool query1(wbem_object & obj, const char * qstr, ...) /*const*/
 183        __attribute_format_printf(3, 4);
 184
 185 private:
 186   com_intf_ptr<IWbemServices> m_intf;
 187 };
 188
 189 #endif // WMIQUERY_H