GH #2689: Added tryWait() into Process and ProcessHandle. Handle kill()-ed UNIX process exit codes.

Foundation/include/Poco/Process.h

@@ -66,6 +66,11 @@ public:
 		/// Waits for the process to terminate
 		/// and returns the exit code of the process.
 
+	int tryWait() const;
+ 		/// Checks that process is terminated
+ 		/// and returns the exit code of the process.
+ 		/// If the process is still running, returns -1.
+
 protected:
 	ProcessHandle(ProcessHandleImpl* pImpl);
 
@@ -211,6 +216,10 @@ public:
 		/// Waits for the process specified by handle to terminate
 		/// and returns the exit code of the process.
 
+	static int tryWait(const ProcessHandle& handle);
+ 		/// Checks that process is finished and returns the exit code of the
+ 		/// process. If the process is still running, returns -1.
+
 	static bool isRunning(const ProcessHandle& handle);
 		/// check if the process specified by handle is running or not
 		///

Foundation/include/Poco/Process_UNIX.h

@@ -39,6 +39,7 @@ public:
 
 	pid_t id() const;
 	int wait() const;
+	int tryWait() const;
 
 private:
 	pid_t _pid;

Foundation/include/Poco/Process_VX.h

@@ -41,6 +41,7 @@ public:
 
 	int id() const;
 	int wait() const;
+	int tryWait() const;
 
 private:
 	int _pid;

Foundation/include/Poco/Process_WIN32.h

@@ -40,6 +40,7 @@ public:
 	UInt32 id() const;
 	HANDLE process() const;
 	int wait() const;
+	int tryWait() const;
 	void closeHandle();
 
 private:

Foundation/include/Poco/Process_WIN32U.h

@@ -40,6 +40,7 @@ public:
 	UInt32 id() const;
 	HANDLE process() const;
 	int wait() const;
+	int tryWait() const;
 	void closeHandle();
 
 private:

Foundation/include/Poco/Process_WINCE.h

@@ -40,6 +40,7 @@ public:
 	UInt32 id() const;
 	HANDLE process() const;
 	int wait() const;
+	int tryWait() const;
 	void closeHandle();
 
 private:

Foundation/src/Process.cpp

@@ -110,6 +110,12 @@ int ProcessHandle::wait() const
 }
 
 
+int ProcessHandle::tryWait() const
+{
+	return _pImpl->tryWait();
+}
+
+
 //
 // Process
 //
@@ -166,6 +172,12 @@ int Process::wait(const ProcessHandle& handle)
 }
 
 
+int Process::tryWait(const ProcessHandle& handle)
+{
+	return handle.tryWait();
+}
+
+
 void Process::kill(ProcessHandle& handle)
 {
 	killImpl(*handle._pImpl);

Foundation/src/Process_UNIX.cpp

@@ -66,7 +66,31 @@ int ProcessHandleImpl::wait() const
 	while (rc < 0 && errno == EINTR);
 	if (rc != _pid)
 		throw SystemException("Cannot wait for process", NumberFormatter::format(_pid));
+
+	if (WIFEXITED(status)) // normal termination
 		return WEXITSTATUS(status);
+	else // termination by a signal
+		return 256 + WTERMSIG(status);
+}
+
+
+int ProcessHandleImpl::tryWait() const
+{
+	int status;
+	int rc;
+	do
+	{
+		rc = waitpid(_pid, &status, WNOHANG);
+	}
+	while (rc < 0 && errno == EINTR);
+	if (rc == 0)
+		return -1;
+	if (rc != _pid)
+		throw SystemException("Cannot wait for process", NumberFormatter::format(_pid));
+	if (WIFEXITED(status)) // normal termination
+		return WEXITSTATUS(status);
+	else // termination by a signal
+		return 256 + WTERMSIG(status);
 }
 
 

Foundation/src/Process_VX.cpp

@@ -45,6 +45,12 @@ int ProcessHandleImpl::wait() const
 }
 
 
+int ProcessHandleImpl::tryWait() const
+{
+	throw Poco::NotImplementedException("Process::tryWait()");
+}
+
+
 //
 // ProcessImpl
 //

Foundation/src/Process_WIN32.cpp

@@ -74,6 +74,18 @@ int ProcessHandleImpl::wait() const
 }
 
 
+int ProcessHandleImpl::tryWait() const
+{
+	DWORD exitCode;
+	if (GetExitCodeProcess(_hProcess, &exitCode) == 0)
+		throw SystemException("Cannot get exit code for process", NumberFormatter::format(_pid));
+	if (exitCode == STILL_ACTIVE)
+		return -1;
+	else
+		return exitCode;
+}
+
+
 //
 // ProcessImpl
 //

Foundation/src/Process_WIN32U.cpp

@@ -78,6 +78,18 @@ int ProcessHandleImpl::wait() const
 }
 
 
+int ProcessHandleImpl::tryWait() const
+{
+	DWORD exitCode;
+	if (GetExitCodeProcess(_hProcess, &exitCode) == 0)
+		throw SystemException("Cannot get exit code for process", NumberFormatter::format(_pid));
+	if (exitCode == STILL_ACTIVE)
+		return -1;
+	else
+		return exitCode;
+}
+
+
 //
 // ProcessImpl
 //

Foundation/src/Process_WINCE.cpp

@@ -73,6 +73,18 @@ int ProcessHandleImpl::wait() const
 }
 
 
+int ProcessHandleImpl::tryWait() const
+{
+	DWORD exitCode;
+	if (GetExitCodeProcess(_hProcess, &exitCode) == 0)
+		throw SystemException("Cannot get exit code for process", NumberFormatter::format(_pid));
+	if (exitCode == STILL_ACTIVE)
+		return -1;
+	else
+		return exitCode;
+}
+
+
 //
 // ProcessImpl
 //