Make storing non-trivial data in wxThreadSpecificInfo possible.

[wxWidgets.git] / interface / wx / snglinst.h

diff --git a/interface/wx/snglinst.h b/interface/wx/snglinst.h
index b24130c399f04eea99615e991a26ebd10e3cf897..2801cec57f8f6c26f20d373763f27d0cec142119 100644 (file)
--- a/interface/wx/snglinst.h
+++ b/interface/wx/snglinst.h
@@ -2,42 +2,40 @@
 // Name:        snglinst.h
 // Purpose:     interface of wxSingleInstanceChecker
 // Author:      wxWidgets team
 // Name:        snglinst.h
 // Purpose:     interface of wxSingleInstanceChecker
 // Author:      wxWidgets team

-// RCS-ID:      $Id$
-// Licence:     wxWindows license
+// Licence:     wxWindows licence

 /////////////////////////////////////////////////////////////////////////////
 
 /**
     @class wxSingleInstanceChecker
 /////////////////////////////////////////////////////////////////////////////
 
 /**
     @class wxSingleInstanceChecker

-    @wxheader{snglinst.h}

 
     wxSingleInstanceChecker class allows to check that only a single instance of a
 
     wxSingleInstanceChecker class allows to check that only a single instance of a

-    program is running. To do it, you should create an object of this class. As
-    long as this object is alive, calls to
-    wxSingleInstanceChecker::IsAnotherRunning from
-    other processes will return @true.
+    program is running.
+
+    To do it, you should create an object of this class. As long as this object
+    is alive, calls to wxSingleInstanceChecker::IsAnotherRunning from other
+    processes will return @true.

 
     As the object should have the life span as big as possible, it makes sense to
 
     As the object should have the life span as big as possible, it makes sense to

-    create it either as a global or in wxApp::OnInit. For
-    example:
+    create it either as a global or in wxApp::OnInit.
+    For example:

 
     @code
     bool MyApp::OnInit()
     {
 
     @code
     bool MyApp::OnInit()
     {

-        const wxString name = wxString::Format("MyApp-%s", wxGetUserId().c_str());
-        m_checker = new wxSingleInstanceChecker(name);
-        if ( m_checker-IsAnotherRunning() )
+        m_checker = new wxSingleInstanceChecker;
+        if ( m_checker->IsAnotherRunning() )

         {
             wxLogError(_("Another program instance is already running, aborting."));
 
         {
             wxLogError(_("Another program instance is already running, aborting."));
 

-            delete m_checker; // OnExit() won't be called if we return @false
-            m_checker = @NULL;
+            delete m_checker; // OnExit() won't be called if we return false
+            m_checker = NULL;

 
 

-            return @false;
+            return false;

         }
 
         ... more initializations ...
 
         }
 
         ... more initializations ...
 

-        return @true;
+        return true;

     }
 
     int MyApp::OnExit()
     }
 
     int MyApp::OnExit()


@@ -48,59 +46,100 @@
     }
     @endcode
 
     }
     @endcode
 

-    Note using wxGetUserId() to construct the name: this
-    allows different user to run the application concurrently which is usually the
-    intended goal. If you don't use the user name in the wxSingleInstanceChecker
-    name, only one user would be able to run the application at a time.
+    Note that by default wxSingleInstanceChecker::CreateDefault() is used to
+    create the checker meaning that it will be initialized differently for
+    different users and thus will allow different users to run the application
+    concurrently which is usually the required behaviour. However if only a
+    single instance of a program should be running system-wide, you need to
+    call Create() with a custom name which does @em not include wxGetUserId().

 
     This class is implemented for Win32 and Unix platforms (supporting @c fcntl()
     system call, but almost all of modern Unix systems do) only.
 
     @library{wxbase}
 
     This class is implemented for Win32 and Unix platforms (supporting @c fcntl()
     system call, but almost all of modern Unix systems do) only.
 
     @library{wxbase}

-    @category{misc}
+    @category{appmanagement}

 */
 class wxSingleInstanceChecker
 {
 public:
     /**
 */
 class wxSingleInstanceChecker
 {
 public:
     /**

-        Like Create() but without
-        error checking.
+        Default constructor.
+
+        You may call Create() after using it or directly call
+        IsAnotherRunning() in which case CreateDefault() will be implicitly
+        used.
+    */
+    wxSingleInstanceChecker();
+
+    /**
+        Constructor calling Create().
+
+        This constructor does exactly the same thing as Create() but doesn't
+        allow to check for errors.

     */
     wxSingleInstanceChecker(const wxString& name,
                             const wxString& path = wxEmptyString);
 
     /**
         Destructor frees the associated resources.
     */
     wxSingleInstanceChecker(const wxString& name,
                             const wxString& path = wxEmptyString);
 
     /**
         Destructor frees the associated resources.

-        Note that it is not virtual, this class is not meant to be used polymorphically
+
+        Note that it is not virtual, this class is not meant to be used polymorphically.

     */
     ~wxSingleInstanceChecker();
 
     /**
         Initialize the object if it had been created using the default constructor.
     */
     ~wxSingleInstanceChecker();
 
     /**
         Initialize the object if it had been created using the default constructor.

+

         Note that you can't call Create() more than once, so calling it if the
         Note that you can't call Create() more than once, so calling it if the

-        @ref wxsingleinstancechecker() "non default ctor"
-        had been used is an error.
+        non default ctor had been used is an error.

 
         @param name
 
         @param name

-            must be given and be as unique as possible. It is used as the
+            Must be given and be as unique as possible. It is used as the

             mutex name under Win32 and the lock file name under Unix.
             mutex name under Win32 and the lock file name under Unix.

-            GetAppName() and wxGetUserId()
-            are commonly used to construct this parameter.
+            wxApp::GetAppName() and wxGetUserId() are commonly used to construct
+            this parameter.

         @param path
         @param path

-            is optional and is ignored under Win32 and used as the directory to
-            create the lock file in under Unix (default is
-            wxGetHomeDir())
-
-        @return Returns @false if initialization failed, it doesn't mean that
-                 another instance is running - use  IsAnotherRunning()
-                 to check for it.
+            The path is optional and is ignored under Win32 and used as the
+            directory to create the lock file in under Unix
+            (default is wxGetHomeDir()).
+
+        @return
+            Returns @false if initialization failed, it doesn't mean that
+            another instance is running -- use IsAnotherRunning() to check for
+            it.
+
+        @note
+            One of possible reasons while Create() may fail on Unix is that the lock
+            file used for checking already exists but was not created by the user.
+            Therefore applications shouldn't treat failure of this function as fatal
+            condition, because doing so would open them to the possibility of a
+            Denial of Service attack. Instead, they should alert the user about
+            the problem and offer to continue execution without checking if
+            another instance is running.

     */
     bool Create(const wxString& name,
                 const wxString& path = wxEmptyString);
 
     /**
     */
     bool Create(const wxString& name,
                 const wxString& path = wxEmptyString);
 
     /**

-        Returns @true if another copy of this program is already running, @false
-        otherwise.
+        Calls Create() with default name.
+
+        This method simply calls Create() with a string composed of
+        wxApp::GetAppName() and wxGetUserId().
+
+        Because this method uses wxApp::GetAppName(), it may only be called
+        after the global application was constructed.
+
+        @since 2.9.1
+     */
+    bool CreateDefault();
+
+    /**
+        Returns @true if another copy of this program is already running and
+        @false otherwise.
+
+        Notice that if the object was created using the default constructor
+        Create() hadn't been called before this method, it will call
+        CreateDefault() automatically.

     */
     bool IsAnotherRunning() const;
 };
     */
     bool IsAnotherRunning() const;
 };