From 9c193777a9acfc6177d4114ff41bfd0df281b14e Mon Sep 17 00:00:00 2001
From: Jonas 'Sortie' Termansen <sortie@maxsi.org>
Date: Thu, 1 Mar 2012 14:31:12 +0100
Subject: [PATCH] Pipes now return 0 (EOF) if no data and no fds can write.

---
 sortix/pipe.cpp | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/sortix/pipe.cpp b/sortix/pipe.cpp
index 47de660a..5e56c2a5 100644
--- a/sortix/pipe.cpp
+++ b/sortix/pipe.cpp
@@ -51,6 +51,8 @@ namespace Sortix
 		size_t bufferused;
 		Event readevent;
 		Event writeevent;
+		bool anyreading;
+		bool anywriting;
 
 	public:
 		virtual ssize_t Read(byte* dest, size_t count);
@@ -58,6 +60,10 @@ namespace Sortix
 		virtual bool IsReadable();
 		virtual bool IsWritable();
 
+	public:
+		void NotReading();
+		void NotWriting();
+
 	};
 
 	DevPipeStorage::DevPipeStorage(byte* buffer, size_t buffersize)
@@ -66,6 +72,8 @@ namespace Sortix
 		this->buffersize = buffersize;
 		this->bufferoffset = 0;
 		this->bufferused = 0;
+		this->anyreading = true;
+		this->anywriting = true;
 	}
 
 	DevPipeStorage::~DevPipeStorage()
@@ -93,6 +101,8 @@ namespace Sortix
 			return amount + Read(dest + amount, count - amount);
 		}
 
+		if ( !anywriting ) { return 0; }
+
 		Error::Set(EBLOCKING);
 		readevent.Register();
 		return -1;
@@ -100,6 +110,7 @@ namespace Sortix
 
 	ssize_t DevPipeStorage::Write(const byte* src, size_t count)
 	{
+		if ( !anyreading ) { /* TODO: SIGPIPE */ }
 		if ( count == 0 ) { return 0; }
 		if ( bufferused < buffersize )
 		{
@@ -120,6 +131,9 @@ namespace Sortix
 		return -1;
 	}
 
+	void DevPipeStorage::NotReading() { anyreading = false; }
+	void DevPipeStorage::NotWriting() { anywriting = false; }
+
 	class DevPipeReading : public DevStream
 	{
 	public:
@@ -148,6 +162,7 @@ namespace Sortix
 
 	DevPipeReading::~DevPipeReading()
 	{
+		((DevPipeStorage*) stream)->NotReading();
 		stream->Unref();
 	}
 
@@ -200,6 +215,7 @@ namespace Sortix
 
 	DevPipeWriting::~DevPipeWriting()
 	{
+		((DevPipeStorage*) stream)->NotWriting();
 		stream->Unref();
 	}