From 4b075b4a7ed921be62740c302edeebcd8b06ca29 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Thu, 9 Oct 2014 20:42:57 +0300
Subject: [PATCH] Support redirecting ExternalTask's stdin/stdout from/to a
 file

---
 source/externaltask.cpp | 67 +++++++++++++++++++++++++++++++++--------
 source/externaltask.h   | 19 +++++++++---
 2 files changed, 69 insertions(+), 17 deletions(-)

diff --git a/source/externaltask.cpp b/source/externaltask.cpp
index 3cc8eca..257d131 100644
--- a/source/externaltask.cpp
+++ b/source/externaltask.cpp
@@ -16,8 +16,8 @@ ExternalTask::ExternalTask(const Arguments &a, const FS::Path &wd):
 	work_dir(wd),
 	process(0),
 	exit_code(-1),
-	stdout_dest(PASSTHROUGH),
-	stderr_dest(PASSTHROUGH),
+	stdout_action(PASSTHROUGH),
+	stderr_action(PASSTHROUGH),
 	capture_pipe(0)
 {
 	if(argv.empty())
@@ -45,35 +45,61 @@ string ExternalTask::get_command() const
 		}
 	}
 
+	if(!stdin_file.empty())
+	{
+		cmd += " <";
+		cmd += stdin_file.str();
+	}
+
+	if(stdout_action==REDIRECT)
+	{
+		cmd += " >";
+		cmd += stdout_file.str();
+	}
+
 	return cmd;
 }
 
 void ExternalTask::start()
 {
 	IO::File *devnull = 0;
+	IO::File *infile = 0;
+	IO::File *outfile = 0;
 
 	prepare();
 
 	process = new Process;
 
-	if(stdout_dest==IGNORE || stderr_dest==IGNORE)
+	if(stdout_action==IGNORE || stderr_action==IGNORE)
 	{
 		devnull = new IO::File("/dev/null", IO::M_WRITE);
-		if(stdout_dest==IGNORE)
+		if(stdout_action==IGNORE)
 			process->redirect_cout(*devnull);
-		if(stderr_dest==IGNORE)
+		if(stderr_action==IGNORE)
 			process->redirect_cerr(*devnull);
 	}
 
-	if(stdout_dest==CAPTURE || stderr_dest==CAPTURE)
+	if(stdout_action==REDIRECT)
+	{
+		outfile = new IO::File((work_dir/stdout_file).str(), IO::M_WRITE);
+		process->redirect_cout(*outfile);
+	}
+
+	if(stdout_action==CAPTURE || stderr_action==CAPTURE)
 	{
 		capture_pipe = new IO::Pipe;
-		if(stdout_dest==CAPTURE)
+		if(stdout_action==CAPTURE)
 			process->redirect_cout(*capture_pipe);
-		if(stderr_dest==CAPTURE)
+		if(stderr_action==CAPTURE)
 			process->redirect_cerr(*capture_pipe);
 	}
 
+	if(!stdin_file.empty())
+	{
+		infile = new IO::File((work_dir/stdin_file).str());
+		process->redirect_cin(*infile);
+	}
+
 	if(!work_dir.empty())
 		process->set_working_directory(work_dir);
 
@@ -83,6 +109,8 @@ void ExternalTask::start()
 		capture_pipe->set_mode(IO::M_READ);
 
 	delete devnull;
+	delete infile;
+	delete outfile;
 }
 
 Task::Status ExternalTask::check()
@@ -126,14 +154,29 @@ Task::Status ExternalTask::do_wait(bool block)
 	return exit_code ? ERROR : SUCCESS;
 }
 
-void ExternalTask::set_stdout(Destination d)
+void ExternalTask::set_stdin(const FS::Path &f)
+{
+	stdin_file = f;
+}
+
+void ExternalTask::set_stdout(StreamAction a)
+{
+	if(a==REDIRECT)
+		throw invalid_argument("ExternalTask::set_stdout");
+	stdout_action = a;
+}
+
+void ExternalTask::set_stdout(const FS::Path &f)
 {
-	stdout_dest = d;
+	stdout_action = REDIRECT;
+	stdout_file = f;
 }
 
-void ExternalTask::set_stderr(Destination d)
+void ExternalTask::set_stderr(StreamAction a)
 {
-	stderr_dest = d;
+	if(a==REDIRECT)
+		throw invalid_argument("ExternalTask::set_stdout");
+	stderr_action = a;
 }
 
 string ExternalTask::run_and_capture_output(const Arguments &argv, const FS::Path &wd)
diff --git a/source/externaltask.h b/source/externaltask.h
index 992df5c..00465f3 100644
--- a/source/externaltask.h
+++ b/source/externaltask.h
@@ -16,10 +16,11 @@ be captured.
 class ExternalTask: public Task
 {
 public:
-	enum Destination
+	enum StreamAction
 	{
 		PASSTHROUGH,  //< Do not touch the stream
 		CAPTURE,      //< Capture the stream
+		REDIRECT,     //< Redirect the stream to/from a file
 		IGNORE        //< Redirect the stream to oblivion
 	};
 
@@ -30,8 +31,10 @@ private:
 	Msp::FS::Path work_dir;
 	Msp::Process *process;
 	int exit_code;
-	Destination stdout_dest;
-	Destination stderr_dest;
+	Msp::FS::Path stdin_file;
+	StreamAction stdout_action;
+	Msp::FS::Path stdout_file;
+	StreamAction stderr_action;
 	Msp::IO::Pipe *capture_pipe;
 	std::string output;
 
@@ -51,11 +54,17 @@ private:
 	Status do_wait(bool);
 
 public:
+	/// Redirect stdin from a file.  Has no effect after the task is started.
+	void set_stdin(const Msp::FS::Path &);
+
 	/// Sets destination for stdout.  Has no effect after the task is started.
-	void set_stdout(Destination);
+	void set_stdout(StreamAction);
+
+	/// Redirect stdout to a file.  Has no effect after the task is started.
+	void set_stdout(const Msp::FS::Path &);
 
 	/// Sets destination for stderr.  Has no effect after the task is started.
-	void set_stderr(Destination);
+	void set_stderr(StreamAction);
 
 	/** Returns captured output, if any.  This may be called while the task is
 	still running, but it will always return all output. */
-- 
2.45.2