Whole installer

installer/src/installer-lib/record.cpp

 /**
- * \file record.cpp Implementation of Session class.
- */
+* \file record.cpp Implementation of Record class.
+*/
 
+#include "installer-lib.h"
 #include "record.h"
 #include "msiquery.h"
 
 //-----------------------------------------------------------------------------------------
 // Record
 //-----------------------------------------------------------------------------------------
 Record::Record( unsigned int n_fields )
-  : n_fields( n_fields )
 {
   _handle = MsiCreateRecord( n_fields ) ;
   if ( ! _handle )
   {
-    throw std::runtime_error( "Failed to create record" ) ;
+    throw windows_api_error( "MsiCreateRecord", 0 ) ;
   }
 }
 
 Record::~Record()
 {
-  MsiCloseHandle( _handle ) ;
+  if ( _handle != 0 )
+  {
+    MsiCloseHandle( _handle ) ;
+  }
 }
 
-void 
-Record::assign_string( unsigned int field_index, std::wstring value )
+void Record::only_non_null()
 {
-  MsiRecordSetString( _handle, field_index, value.c_str() ) ;
+  if ( _handle == 0 )
+  {
+    throw std::runtime_error( "Operation only permitted for non-null objects" ) ;
+  }
+}
+
+void Record::assign_string( unsigned int field_index, const char *value )
+{
+  only_non_null() ;
+  MsiRecordSetStringA( _handle, field_index, value ) ;
+}
+
+void Record::assign_string( unsigned int field_index, const wchar_t *value )
+{
+  only_non_null() ;
+  MsiRecordSetStringW( _handle, field_index, value ) ;
+}
+
+/**
+* \par Implementation
+*    - MSDN [MsiRecordGetString](http://msdn.microsoft.com/en-us/library/aa370368%28v=vs.85%29.aspx)
+*/
+std::wstring Record::value_string( unsigned int field_index )
+{
+  static wchar_t initial_buffer[ 1024 ] = L"" ;
+  DWORD length = 1023 ; // one less than the buffer length to hold a terminating null character
+  UINT x = MsiRecordGetStringW( _handle, field_index, initial_buffer, & length ) ;
+  if ( x == ERROR_SUCCESS )
+  {
+    return std::wstring( initial_buffer ) ;
+  }
+  if ( x == ERROR_MORE_DATA )
+  {
+    // Future: handle longer strings.
+    /*
+    * The present custom action only uses this function for strings that appear in dialog boxes.
+    * A thousand characters is about a dozen lines of text, which is far more than enough.
+    */
+    throw not_yet_supported( "retrieving string values longer than 1023 from a record" ) ;
+  }
+  throw windows_api_error( "MsiRecordGetStringW", x ) ;
+}
+
+size_t Record::n_fields() const
+{
+  unsigned int x = MsiRecordGetFieldCount( _handle ) ;
+  if ( x == 0xFFFFFFFF )
+  {
+    throw windows_api_error( "MsiRecordGetFieldCount", x, "invalid handle" ) ;
+  }
+  return x ;
 }