From 56af6cbdeec4c88127d34ccf4313adf03e04896a Mon Sep 17 00:00:00 2001
From: Tobias Taschner <TcT2k@users.noreply.github.com>
Date: Thu, 1 Nov 2018 11:54:30 +0100
Subject: [PATCH] Implement Cancel for WinHTTP backend

---
 include/wx/webrequest.h        |  6 ++++--
 src/common/webrequest.cpp      | 18 +++++++++++++-----
 src/msw/webrequest_winhttp.cpp | 13 ++++++++-----
 3 files changed, 25 insertions(+), 12 deletions(-)

diff --git a/include/wx/webrequest.h b/include/wx/webrequest.h
index 60d874266d..edd130c338 100644
--- a/include/wx/webrequest.h
+++ b/include/wx/webrequest.h
@@ -106,6 +106,8 @@ protected:
 
     bool CheckServerStatus();
 
+    static bool IsActiveState(State state);
+
 private:
     wxWebSession& m_session;
     int m_id;
@@ -141,10 +143,10 @@ public:
 
     wxString AsString(wxMBConv* conv = NULL) const;
 
-    void ReportDataCompleted();
-
     bool Init();
 
+    void Finalize();
+
     virtual wxString GetFileName() const;
 
 protected:
diff --git a/src/common/webrequest.cpp b/src/common/webrequest.cpp
index be00b4a5be..bca423a6a7 100644
--- a/src/common/webrequest.cpp
+++ b/src/common/webrequest.cpp
@@ -71,6 +71,11 @@ bool wxWebRequest::CheckServerStatus()
         return true;
 }
 
+bool wxWebRequest::IsActiveState(State state)
+{
+    return (state == State_Active || state == State_Unauthorized);
+}
+
 void wxWebRequest::SetData(const wxString& text, const wxString& contentType, const wxMBConv& conv)
 {
     m_dataText = text.mb_str(conv);
@@ -100,15 +105,20 @@ void wxWebRequest::SetData(wxSharedPtr<wxInputStream> dataStream, const wxString
 void wxWebRequest::SetState(State state, const wxString & failMsg)
 {
     // Add a reference while the request is active
-    if (state == State_Active && m_state != State_Active && m_state != State_Unauthorized)
+    if ( IsActiveState(state) && !IsActiveState(m_state) )
         IncRef();
 
+    m_state = state;
+
     // Trigger the event in the main thread
     CallAfter(&wxWebRequest::ProcessStateEvent, state, failMsg);
 }
 
 void wxWebRequest::ProcessStateEvent(State state, const wxString& failMsg)
 {
+    if (!IsActiveState(state) && GetResponse())
+        GetResponse()->Finalize();
+
     wxString responseFileName;
 
     wxWebRequestEvent evt(wxEVT_WEBREQUEST_STATE, GetId(), state,
@@ -127,10 +137,8 @@ void wxWebRequest::ProcessStateEvent(State state, const wxString& failMsg)
         wxRemoveFile(responseFileName);
 
     // Remove reference after the request is no longer active
-    if (state == State_Completed || state == State_Failed ||
-        state == State_Cancelled)
+    if ( !IsActiveState(state) )
         DecRef();
-    m_state = state;
 }
 
 //
@@ -262,7 +270,7 @@ wxString wxWebResponse::GetFileName() const
     return m_file.GetName();
 }
 
-void wxWebResponse::ReportDataCompleted()
+void wxWebResponse::Finalize()
 {
     if ( m_request.GetStorage() == wxWebRequest::Storage_File )
         m_file.Close();
diff --git a/src/msw/webrequest_winhttp.cpp b/src/msw/webrequest_winhttp.cpp
index 55397aac54..1d1d6bb617 100644
--- a/src/msw/webrequest_winhttp.cpp
+++ b/src/msw/webrequest_winhttp.cpp
@@ -176,14 +176,12 @@ void wxWebRequestWinHTTP::HandleCallback(DWORD dwInternetStatus,
         case WINHTTP_CALLBACK_STATUS_READ_COMPLETE:
             if ( dwStatusInformationLength > 0 )
             {
-                if ( !m_response->ReportAvailableData(dwStatusInformationLength) )
+                if ( !m_response->ReportAvailableData(dwStatusInformationLength) &&
+                    GetState() != State_Cancelled )
                     SetFailedWithLastError();
             }
             else
-            {
-                m_response->ReportDataCompleted();
                 SetState(State_Completed);
-            }
             break;
         case WINHTTP_CALLBACK_STATUS_WRITE_COMPLETE:
             WriteData();
@@ -340,7 +338,12 @@ void wxWebRequestWinHTTP::SendRequest()
 
 void wxWebRequestWinHTTP::Cancel()
 {
-    wxFAIL_MSG("not implemented");
+    SetState(State_Cancelled);
+    if ( m_request != NULL )
+    {
+        ::WinHttpCloseHandle(m_request);
+        m_request = NULL;
+    }
 }
 
 wxWebResponse* wxWebRequestWinHTTP::GetResponse()