X-Git-Url: https://git.ucc.asn.au/?p=progcomp2012.git;a=blobdiff_plain;f=judge%2Fmanager%2Fprogram.cpp;h=031d4113febc78d7f41cc9e10f0e7481ceb013f3;hp=588f7146c323f19f47369a5ab52845c40ebbc12f;hb=341297b4dce9528d54fe9dceeff0d6dc33f70abe;hpb=1a03b2543b67f0551e62babec4cd119f1e0e4640

diff --git a/judge/manager/program.cpp b/judge/manager/program.cpp
index 588f714..031d411 100644
--- a/judge/manager/program.cpp
+++ b/judge/manager/program.cpp
@@ -20,7 +20,7 @@ using namespace std;
  *	The child process closes unused sides of the pipe, and then calls exec to replace itself with the AI program
  *	The parent process closes unused sides of the pipe, and sets up member variables - associates streams with the pipe fd's for convenience.
  */
-Program::Program(const char * executablePath) : input(NULL), output(NULL), pid(0)
+Program::Program(const char * executablePath) : input(NULL), output(NULL), pid(0), paused(false)
 {
 	//See if file exists and is executable...
 	if (access(executablePath, X_OK) != 0)
@@ -100,8 +100,42 @@ Program::~Program()
 	
 }
 
+/**
+ * Forces the program to pause by sending SIGSTOP
+ * Program can be resumed by calling Continue() (which sends SIGCONT)
+ * @returns true if the program could be paused, false if it couldn't (probably because it wasn't running)
+ */
+bool Program::Pause()
+{
+	if (pid > 0 && kill(pid,SIGSTOP) == 0)
+	{
+		paused = true;
+		return true;
+	}
+	return false;
+}
 
+/**
+ * Causes a paused program to continue
+ * @returns true if the program could be continued, false if it couldn't (probably because it wasn't running)
+ */
+bool Program::Continue()
+{
+	if (pid > 0 && kill(pid,SIGCONT) == 0)
+	{
+		paused = false;
+		return true;
+	}
+	return false;
+}
 
+/**
+ * @returns true iff the program is paused
+ */
+bool Program::Paused() const
+{
+	return paused;
+}
 
 
 /**
@@ -140,12 +174,13 @@ bool Program::SendMessage(const char * print, ...)
  */
 bool Program::GetMessage(string & buffer, double timeout)
 {
-	if (!Running())
+	if (!Running() || timeout == 0)
 		return false;
 
 	assert(&buffer != NULL);
 	GetterThread getterThread(input, buffer);
 	assert(&(getterThread.buffer) != NULL);
+
 	TimerThread timerThread(timeout*1000000);
 
 	getterThread.Start();
@@ -164,7 +199,8 @@ bool Program::GetMessage(string & buffer, double timeout)
 	}
 
 	getterThread.Stop();
-	timerThread.Stop();
+	if (timeout > 0)
+		timerThread.Stop();