1. wxProcess changes to make capturing subprocess output easier (and more

reliable), now works in both sync and async modes
2. wxSafeYieldBug() corrected, wxWindowDisabler which is now used in it
   added and documented
3. exec sample updated to illustrate capturing the subprocess output
4. wxStreamBase::IsOk() added
5. wxInputStream::Eof() added and non-blocking Eof() implementation in
   wxPipeInputStream used by wxExecute


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@6400 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

samples/exec/exec.cpp

@@ -66,6 +66,10 @@ public:
     virtual bool OnInit();
 };
 
+// Define an array of process pointers used by MyFrame
+class MyPipedProcess;
+WX_DEFINE_ARRAY(MyPipedProcess *, MyProcessesArray);
+
 // Define a new frame type: this is going to be our main frame
 class MyFrame : public wxFrame
 {
@@ -86,7 +90,12 @@ public:
 
     void OnAbout(wxCommandEvent& event);
 
+    // polling output of async processes
+    void OnIdle(wxIdleEvent& event);
+
     // for MyPipedProcess
+    void OnProcessTerminated(MyPipedProcess *process)
+        { m_running.Remove(process); }
     wxListBox *GetLogListBox() const { return m_lbox; }
 
 private:
@@ -94,6 +103,8 @@ private:
 
     wxListBox *m_lbox;
 
+    MyProcessesArray m_running;
+
     // any class wishing to process wxWindows events must use this macro
     DECLARE_EVENT_TABLE()
 };
@@ -125,10 +136,12 @@ public:
     MyPipedProcess(MyFrame *parent, const wxString& cmd)
         : MyProcess(parent, cmd)
         {
-            m_needPipe = TRUE;
+            Redirect();
         }
 
     virtual void OnTerminate(int pid, int status);
+
+    bool HasInput();
 };
 
 // ----------------------------------------------------------------------------
@@ -169,6 +182,8 @@ BEGIN_EVENT_TABLE(MyFrame, wxFrame)
     EVT_MENU(Exec_DDEExec, MyFrame::OnDDEExec)
 
     EVT_MENU(Exec_About, MyFrame::OnAbout)
+
+    EVT_IDLE(MyFrame::OnIdle)
 END_EVENT_TABLE()
 
 // Create a new application object: this macro will allow wxWindows to create
@@ -347,17 +362,58 @@ void MyFrame::OnExecWithRedirect(wxCommandEvent& WXUNUSED(event))
     if ( !cmd )
         return;
 
-    wxProcess *process = new MyPipedProcess(this, cmd);
-    if ( !wxExecute(cmd, FALSE /* async */, process) )
+    bool sync;
+    switch ( wxMessageBox(_T("Execute it synchronously?"),
+                          _T("Exec question"),
+                          wxYES_NO | wxCANCEL | wxICON_QUESTION, this) )
     {
-        wxLogError(_T("Execution of '%s' failed."), cmd.c_str());
+        case wxYES:
+            sync = TRUE;
+            break;
 
-        delete process;
+        case wxNO:
+            sync = FALSE;
+            break;
+
+        default:
+            return;
     }
-    else
+
+    if ( sync )
     {
-        m_cmdLast = cmd;
+        wxArrayString output;
+        int code = wxExecute(cmd, output);
+        wxLogStatus(_T("command '%s' terminated with exit code %d."),
+                    cmd.c_str(), code);
+
+        if ( code != -1 )
+        {
+            m_lbox->Append(wxString::Format(_T("--- Output of '%s' ---"),
+                                            cmd.c_str()));
+
+            size_t count = output.GetCount();
+            for ( size_t n = 0; n < count; n++ )
+            {
+                m_lbox->Append(output[n]);
+            }
+        }
     }
+    else // async exec
+    {
+        MyPipedProcess *process = new MyPipedProcess(this, cmd);
+        if ( !wxExecute(cmd, FALSE /* async */, process) )
+        {
+            wxLogError(_T("Execution of '%s' failed."), cmd.c_str());
+
+            delete process;
+        }
+        else
+        {
+            m_running.Add(process);
+        }
+    }
+
+    m_cmdLast = cmd;
 }
 
 void MyFrame::OnDDEExec(wxCommandEvent& WXUNUSED(event))
@@ -402,6 +458,19 @@ void MyFrame::OnDDEExec(wxCommandEvent& WXUNUSED(event))
 #endif // __WINDOWS__
 }
 
+// input polling
+void MyFrame::OnIdle(wxIdleEvent& event)
+{
+    size_t count = m_running.GetCount();
+    for ( size_t n = 0; n < count; n++ )
+    {
+        if ( m_running[n]->HasInput() )
+        {
+            event.RequestMore();
+        }
+    }
+}
+
 // ----------------------------------------------------------------------------
 // MyProcess
 // ----------------------------------------------------------------------------
@@ -415,17 +484,38 @@ void MyProcess::OnTerminate(int pid, int status)
     delete this;
 }
 
+// ----------------------------------------------------------------------------
+// MyPipedProcess
+// ----------------------------------------------------------------------------
+
+bool MyPipedProcess::HasInput()
+{
+    wxInputStream& is = *GetInputStream();
+    if ( !is.Eof() )
+    {
+        wxTextInputStream tis(is);
+
+        // this assumes that the output is always line buffered
+        wxString msg;
+        msg << m_cmd << _T(": ") << tis.ReadLine();
+
+        m_parent->GetLogListBox()->Append(msg);
+
+        return TRUE;
+    }
+    else
+    {
+        return FALSE;
+    }
+}
+
 void MyPipedProcess::OnTerminate(int pid, int status)
 {
-    // show the program output
-    wxListBox *lbox = m_parent->GetLogListBox();
-    lbox->Append(wxString::Format(_T("--- Output of '%s' ---"), m_cmd.c_str()));
+    // show the rest of the output
+    while ( HasInput() )
+        ;
 
-    wxTextInputStream tis(*m_in_stream);
-    while ( !m_in_stream->LastError() )
-    {
-        lbox->Append(tis.ReadLine());
-    }
+    m_parent->OnProcessTerminated(this);
 
     MyProcess::OnTerminate(pid, status);
 }