cmSystemTools: Add callback for Stderr

Factor a common callback type out of StdoutCallback.  Add an equivalent
StderrCallback.  While at it, use "size_t" for the data length instead
of "int".

Teach "ctest --build-and-test" to capture the Stderr callback because
output sent through it is part of the logical CMake process output.

Source/CTest/cmCTestBuildAndTestHandler.cxx

@@ -156,7 +156,7 @@ void CMakeProgressCallback(const char*msg, float , void * s)
 }
 
 //----------------------------------------------------------------------
-void CMakeStdoutCallback(const char* m, int len, void* s)
+void CMakeOutputCallback(const char* m, size_t len, void* s)
 {
   std::string* out = (std::string*)s;
   out->append(m, len);
@@ -170,12 +170,14 @@ public:
   cmCTestBuildAndTestCaptureRAII(cmake& cm, std::string& s): CM(cm)
     {
     cmSystemTools::SetMessageCallback(CMakeMessageCallback, &s);
-    cmSystemTools::SetStdoutCallback(CMakeStdoutCallback, &s);
+    cmSystemTools::SetStdoutCallback(CMakeOutputCallback, &s);
+    cmSystemTools::SetStderrCallback(CMakeOutputCallback, &s);
     this->CM.SetProgressCallback(CMakeProgressCallback, &s);
     }
   ~cmCTestBuildAndTestCaptureRAII()
     {
     this->CM.SetProgressCallback(0, 0);
+    cmSystemTools::SetStderrCallback(0, 0);
     cmSystemTools::SetStdoutCallback(0, 0);
     cmSystemTools::SetMessageCallback(0, 0);
     }

Source/cmSystemTools.cxx

@@ -122,10 +122,12 @@ bool cmSystemTools::s_DisableMessages = false;
 bool cmSystemTools::s_ForceUnixPaths = false;
 
 cmSystemTools::MessageCallback cmSystemTools::s_MessageCallback;
+cmSystemTools::OutputCallback cmSystemTools::s_StdoutCallback;
+cmSystemTools::OutputCallback cmSystemTools::s_StderrCallback;
 cmSystemTools::InterruptCallback cmSystemTools::s_InterruptCallback;
-void (*cmSystemTools::s_StdoutCallback)(const char*, int len, void*);
 void* cmSystemTools::s_MessageCallbackClientData;
-void* cmSystemTools::s_StdoutCallbackClientData = 0;
+void* cmSystemTools::s_StdoutCallbackClientData;
+void* cmSystemTools::s_StderrCallbackClientData;
 void* cmSystemTools::s_InterruptCallbackClientData;
 
 // replace replace with with as many times as it shows up in source.
@@ -259,33 +261,42 @@ void cmSystemTools::SetMessageCallback(MessageCallback f, void* clientData)
   s_MessageCallbackClientData = clientData;
 }
 
-void cmSystemTools::SetStdoutCallback(StdoutCallback f, void* clientData)
+void cmSystemTools::SetStdoutCallback(OutputCallback f, void* clientData)
 {
   s_StdoutCallback = f;
   s_StdoutCallbackClientData = clientData;
 }
 
+void cmSystemTools::SetStderrCallback(OutputCallback f, void* clientData)
+{
+  s_StderrCallback = f;
+  s_StderrCallbackClientData = clientData;
+}
+
 void cmSystemTools::Stdout(const char* s)
 {
-  if(s_StdoutCallback)
+  cmSystemTools::Stdout(s, strlen(s));
+}
+
+void cmSystemTools::Stderr(const char* s)
+{
+  cmSystemTools::Stderr(s, strlen(s));
+}
+
+void cmSystemTools::Stderr(const char* s, size_t length)
+{
+  if(s_StderrCallback)
     {
-    (*s_StdoutCallback)(s, static_cast<int>(strlen(s)),
-                        s_StdoutCallbackClientData);
+    (*s_StderrCallback)(s, length, s_StderrCallbackClientData);
     }
   else
     {
-    std::cout << s;
-    std::cout.flush();
-    }
-}
-
-void cmSystemTools::Stderr(const char* s, int length)
-{
     std::cerr.write(s, length);
     std::cerr.flush();
+    }
 }
 
-void cmSystemTools::Stdout(const char* s, int length)
+void cmSystemTools::Stdout(const char* s, size_t length)
 {
   if(s_StdoutCallback)
     {

Source/cmSystemTools.h

@@ -77,14 +77,17 @@ public:
    */
   static void Message(const char* m, const char* title=0);
 
+  typedef void (*OutputCallback)(const char*, size_t length, void*);
+
   ///! Send a string to stdout
   static void Stdout(const char* s);
-  static void Stdout(const char* s, int length);
-  typedef  void (*StdoutCallback)(const char*, int length, void*);
-  static void SetStdoutCallback(StdoutCallback, void* clientData=0);
+  static void Stdout(const char* s, size_t length);
+  static void SetStdoutCallback(OutputCallback, void* clientData=0);
 
-  ///! Send a string to stderr. Stdout callbacks will not be invoced.
-  static void Stderr(const char* s, int length);
+  ///! Send a string to stderr
+  static void Stderr(const char* s);
+  static void Stderr(const char* s, size_t length);
+  static void SetStderrCallback(OutputCallback, void* clientData=0);
 
 
   typedef bool (*InterruptCallback)(void*);
@@ -471,10 +474,12 @@ private:
   static bool s_DisableMessages;
   static bool s_DisableRunCommandOutput;
   static MessageCallback s_MessageCallback;
-  static StdoutCallback s_StdoutCallback;
+  static OutputCallback s_StdoutCallback;
+  static OutputCallback s_StderrCallback;
   static InterruptCallback s_InterruptCallback;
   static void* s_MessageCallbackClientData;
   static void* s_StdoutCallbackClientData;
+  static void* s_StderrCallbackClientData;
   static void* s_InterruptCallbackClientData;
 };