X-Git-Url: http://nitlanguage.org

diff --git a/lib/standard/stream.nit b/lib/standard/stream.nit
index 88a73ac..745064a 100644
--- a/lib/standard/stream.nit
+++ b/lib/standard/stream.nit
@@ -10,11 +10,18 @@
 # You  are  allowed  to  redistribute it and sell it, alone or is a part of
 # another product.
 
-# This module handle abstract input and output streams
-package stream
+# Input and output streams of characters
+module stream
 
 import string
 
+in "C" `{
+	#include <unistd.h>
+	#include <poll.h>
+	#include <errno.h>
+	#include <string.h>
+`}
+
 # Abstract stream class
 interface IOS
 	# close the stream
@@ -61,7 +68,7 @@ interface IStream
 		return s.to_s
 	end
 
-	# Read a string until the end of the line and append it to `s'.
+	# Read a string until the end of the line and append it to `s`.
 	fun append_line_to(s: Buffer)
 	do
 		loop
@@ -70,13 +77,14 @@ interface IStream
 				if eof then return
 			else
 				var c = x.ascii
-				s.push(c)
+				s.chars.push(c)
 				if c == '\n' then return
 			end
 		end
 	end
 
 	# Is there something to read.
+	# This function returns 'false' if there is something to read.
 	fun eof: Bool is abstract
 end
 
@@ -102,7 +110,7 @@ abstract class BufferedIStream
 		if _buffer_pos >= _buffer.length then
 			return -1
 		end
-		var c = _buffer[_buffer_pos]
+		var c = _buffer.chars[_buffer_pos]
 		_buffer_pos += 1
 		return c.ascii
 	end
@@ -120,7 +128,7 @@ abstract class BufferedIStream
 				k = _buffer.length
 			end
 			while j < k and i > 0 do
-				s.add(_buffer[j])
+				s.add(_buffer.chars[j])
 				j +=  1
 				i -= 1
 			end
@@ -136,7 +144,7 @@ abstract class BufferedIStream
 			var j = _buffer_pos
 			var k = _buffer.length
 			while j < k do
-				s.add(_buffer[j])
+				s.add(_buffer.chars[j])
 				j += 1
 			end
 			_buffer_pos = j
@@ -150,7 +158,7 @@ abstract class BufferedIStream
 		loop
 			# First phase: look for a '\n'
 			var i = _buffer_pos
-			while i < _buffer.length and _buffer[i] != '\n' do i += 1
+			while i < _buffer.length and _buffer.chars[i] != '\n' do i += 1
 
 			# if there is something to append
 			if i > _buffer_pos then
@@ -160,7 +168,7 @@ abstract class BufferedIStream
 				# Copy from the buffer to the string
 				var j = _buffer_pos
 				while j < i do
-					s.add(_buffer[j])
+					s.add(_buffer.chars[j])
 					j += 1
 				end
 			end
@@ -195,7 +203,7 @@ abstract class BufferedIStream
 	# Is the last fill_buffer reach the end 
 	protected fun end_reached: Bool is abstract
 
-	# Allocate a `_buffer' for a given `capacity'.
+	# Allocate a `_buffer` for a given `capacity`.
 	protected fun prepare_buffer(capacity: Int)
 	do
 		_buffer = new Buffer.with_capacity(capacity)
@@ -213,27 +221,28 @@ end
 abstract class FDStream
 	super IOS
 	# File description
-	var _fd: Int
+	var fd: Int
 
-	redef fun close do native_close(_fd)
+	redef fun close do native_close(fd)
 
 	private fun native_close(i: Int): Int is extern "stream_FDStream_FDStream_native_close_1"
 	private fun native_read_char(i: Int): Int is extern "stream_FDStream_FDStream_native_read_char_1"
 	private fun native_read(i: Int, buf: NativeString, len: Int): Int is extern "stream_FDStream_FDStream_native_read_3"
 	private fun native_write(i: Int, buf: NativeString, len: Int): Int is extern "stream_FDStream_FDStream_native_write_3"
+	private fun native_write_char(i: Int, c: Char): Int is extern "stream_FDStream_FDStream_native_write_char_2"
 
-	init(fd: Int) do _fd = fd
+	init(fd: Int) do self.fd = fd
 end
 
 class FDIStream
 	super FDStream
 	super IStream
-	redef readable var _eof: Bool = false
+	redef var eof: Bool = false
 	
 	redef fun read_char
 	do
-		var nb = native_read_char(_fd)
-		if nb == -1 then _eof = true
+		var nb = native_read_char(fd)
+		if nb == -1 then eof = true
 		return nb
 	end
 
@@ -243,17 +252,17 @@ end
 class FDOStream
 	super FDStream
 	super OStream
-	redef readable var _is_writable: Bool
+	redef var is_writable: Bool
 
 	redef fun write(s)
 	do
-		var nb = native_write(_fd, s.to_cstring, s.length)
-		if nb < s.length then _is_writable = false
+		var nb = native_write(fd, s.to_cstring, s.length)
+		if nb < s.length then is_writable = false
 	end
 
 	init(fd: Int)
 	do
-		_is_writable = true
+		is_writable = true
 	end
 end
 
@@ -263,7 +272,95 @@ class FDIOStream
 	super IOStream
 	init(fd: Int)
 	do
-		_fd = fd
-		_is_writable = true
+		self.fd = fd
+		is_writable = true
+	end
+end
+
+redef interface Object
+	# returns first available stream to read or write to
+	# return null on interruption (possibly a signal)
+	protected fun poll( streams : Sequence[FDStream] ) : nullable FDStream
+	do
+		var in_fds = new Array[Int]
+		var out_fds = new Array[Int]
+		var fd_to_stream = new HashMap[Int,FDStream]
+		for s in streams do
+			var fd = s.fd
+			if s isa FDIStream then in_fds.add( fd )
+			if s isa FDOStream then out_fds.add( fd )
+
+			fd_to_stream[fd] = s
+		end
+
+		var polled_fd = intern_poll( in_fds, out_fds )
+
+		if polled_fd == null then
+			return null
+		else
+			return fd_to_stream[polled_fd]
+		end
 	end
+
+	private fun intern_poll(in_fds: Array[Int], out_fds: Array[Int]) : nullable Int is extern import Array[Int].length, Array[Int].[], Int.as(nullable Int) `{
+		int in_len, out_len, total_len;
+		struct pollfd *c_fds;
+		sigset_t sigmask;
+		int i;
+		int first_polled_fd = -1;
+		int result;
+
+		in_len = Array_of_Int_length( in_fds );
+		out_len = Array_of_Int_length( out_fds );
+		total_len = in_len + out_len;
+		c_fds = malloc( sizeof(struct pollfd) * total_len );
+
+		/* input streams */
+		for ( i=0; i<in_len; i ++ ) {
+			int fd;
+			fd = Array_of_Int__index( in_fds, i );
+
+			c_fds[i].fd = fd;
+			c_fds[i].events = POLLIN;
+		}
+
+		/* output streams */
+		for ( i=0; i<out_len; i ++ ) {
+			int fd;
+			fd = Array_of_Int__index( out_fds, i );
+
+			c_fds[i].fd = fd;
+			c_fds[i].events = POLLOUT;
+		}
+
+		/* poll all fds, unlimited timeout */
+		result = poll( c_fds, total_len, -1 );
+
+		if ( result > 0 ) {
+			/* analyse results */
+			for ( i=0; i<total_len; i++ )
+				if ( c_fds[i].revents & c_fds[i].events || /* awaited event */
+					 c_fds[i].revents & POLLHUP ) /* closed */
+				{
+					first_polled_fd = c_fds[i].fd;
+					break;
+				}
+
+			return Int_as_nullable( first_polled_fd );
+		}
+		else if ( result < 0 )
+			fprintf( stderr, "Error in Stream:poll: %s\n", strerror( errno ) );
+
+		return null_Int();
+	`}
+end
+
+# Stream to a String. Mainly used for compatibility with OStream type and tests.
+class StringOStream
+	super OStream
+
+	private var content = new Array[String]
+	redef fun to_s do return content.to_s
+	redef fun is_writable do return true
+	redef fun write(str) do content.add(str)
 end