stream: add a stream class abstracting BSD sockets

Currently only synchronous operation is supported, but this will be extended
with asynchronous methods using the new watcher.

src/libstrongswan/Android.mk

@@ -26,7 +26,7 @@ credentials/sets/callback_cred.c credentials/auth_cfg.c database/database.c \
 database/database_factory.c fetcher/fetcher.c fetcher/fetcher_manager.c eap/eap.c \
 ipsec/ipsec_types.c \
 networking/host.c networking/host_resolver.c networking/packet.c \
-networking/tun_device.c \
+networking/tun_device.c networking/streams/stream.c \
 pen/pen.c plugins/plugin_loader.c plugins/plugin_feature.c processing/jobs/job.c \
 processing/jobs/callback_job.c processing/processor.c processing/scheduler.c \
 processing/watcher.c resolver/resolver_manager.c resolver/rr_set.c \

src/libstrongswan/Makefile.am

@@ -24,7 +24,7 @@ credentials/sets/callback_cred.c credentials/auth_cfg.c database/database.c \
 database/database_factory.c fetcher/fetcher.c fetcher/fetcher_manager.c eap/eap.c \
 ipsec/ipsec_types.c \
 networking/host.c networking/host_resolver.c networking/packet.c \
-networking/tun_device.c \
+networking/tun_device.c networking/streams/stream.c \
 pen/pen.c plugins/plugin_loader.c plugins/plugin_feature.c processing/jobs/job.c \
 processing/jobs/callback_job.c processing/processor.c processing/scheduler.c \
 processing/watcher.c resolver/resolver_manager.c resolver/rr_set.c \
@@ -65,7 +65,7 @@ credentials/auth_cfg.h credentials/credential_set.h credentials/cert_validator.h
 database/database.h database/database_factory.h fetcher/fetcher.h \
 fetcher/fetcher_manager.h eap/eap.h pen/pen.h ipsec/ipsec_types.h \
 networking/host.h networking/host_resolver.h networking/packet.h \
-networking/tun_device.h \
+networking/tun_device.h networking/streams/stream.h \
 resolver/resolver.h resolver/resolver_response.h resolver/rr_set.h \
 resolver/rr.h resolver/resolver_manager.h \
 plugins/plugin_loader.h plugins/plugin.h plugins/plugin_feature.h \

src/libstrongswan/networking/streams/stream.c

@@ -0,0 +1,119 @@
+/*
+ * Copyright (C) 2013 Martin Willi
+ * Copyright (C) 2013 revosec AG
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ */
+
+#include "stream.h"
+
+#include <errno.h>
+#include <unistd.h>
+
+typedef struct private_stream_t private_stream_t;
+
+/**
+ * Private data of an stream_t object.
+ */
+struct private_stream_t {
+
+	/**
+	 * Public stream_t interface.
+	 */
+	stream_t public;
+
+	/**
+	 * Underlying socket
+	 */
+	int fd;
+};
+
+METHOD(stream_t, read_, ssize_t,
+	private_stream_t *this, void *buf, size_t len, bool block)
+{
+	while (TRUE)
+	{
+		ssize_t ret;
+
+		if (block)
+		{
+			ret = read(this->fd, buf, len);
+		}
+		else
+		{
+			ret = recv(this->fd, buf, len, MSG_DONTWAIT);
+			if (ret == -1 && errno == EAGAIN)
+			{
+				/* unify EGAIN and EWOULDBLOCK */
+				errno = EWOULDBLOCK;
+			}
+		}
+		if (ret == -1 && errno == EINTR)
+		{	/* interrupted, try again */
+			continue;
+		}
+		return ret;
+	}
+}
+
+METHOD(stream_t, write_, ssize_t,
+	private_stream_t *this, void *buf, size_t len, bool block)
+{
+	ssize_t ret;
+
+	while (TRUE)
+	{
+		if (block)
+		{
+			ret = write(this->fd, buf, len);
+		}
+		else
+		{
+			ret = send(this->fd, buf, len, MSG_DONTWAIT);
+			if (ret == -1 && errno == EAGAIN)
+			{
+				/* unify EGAIN and EWOULDBLOCK */
+				errno = EWOULDBLOCK;
+			}
+		}
+		if (ret == -1 && errno == EINTR)
+		{	/* interrupted, try again */
+			continue;
+		}
+		return ret;
+	}
+}
+
+METHOD(stream_t, destroy, void,
+	private_stream_t *this)
+{
+	close(this->fd);
+	free(this);
+}
+
+/**
+ * See header
+ */
+stream_t *stream_create_from_fd(int fd)
+{
+	private_stream_t *this;
+
+	INIT(this,
+		.public = {
+			.read = _read_,
+			.write = _write_,
+			.destroy = _destroy,
+		},
+		.fd = fd,
+	);
+
+	return &this->public;
+}

src/libstrongswan/networking/streams/stream.h

@@ -0,0 +1,83 @@
+/*
+ * Copyright (C) 2013 Martin Willi
+ * Copyright (C) 2013 revosec AG
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ */
+
+/**
+ * @defgroup stream stream
+ * @{ @ingroup streams
+ */
+
+#ifndef STREAM_H_
+#define STREAM_H_
+
+typedef struct stream_t stream_t;
+
+#include <library.h>
+
+/**
+ * Constructor function prototype for stream_t.
+ *
+ * @param uri			URI to create a stream for
+ * @return				stream instance, NULL on error
+ */
+typedef stream_t*(*stream_constructor_t)(char *uri);
+
+/**
+ * Abstraction of a Berkley socket using stream semantics.
+ */
+struct stream_t {
+
+	/**
+	 * Read data from the stream.
+	 *
+	 * If "block" is FALSE and no data is available, the function returns -1
+	 * and sets errno to EWOULDBLOCK.
+	 *
+	 * @param buf		data buffer to read into
+	 * @param len		number of bytes to read
+	 * @param block		TRUE to use a blocking read
+	 * @return			number of bytes read, -1 on error
+	 */
+	ssize_t (*read)(stream_t *this, void *buf, size_t len, bool block);
+
+	/**
+	 * Write data to the stream.
+	 *
+	 * If "block" is FALSE and the write would block, the function returns -1
+	 * and sets errno to EWOULDBLOCK.
+	 *
+	 * @param buf		data buffer to write
+	 * @param len		number of bytes to write
+	 * @param block		TRUE to use a blocking write
+	 * @return			number of bytes written, -1 on error
+	 */
+	ssize_t (*write)(stream_t *this, void *buf, size_t len, bool block);
+
+	/**
+	 * Destroy a stream_t.
+	 */
+	void (*destroy)(stream_t *this);
+};
+
+/**
+ * Create a stream from a file descriptor.
+ *
+ * The file descriptor MUST be a socket for non-blocking operation.
+ *
+ * @param fd		file descriptor to wrap into a stream_t
+ * @return			stream instance
+ */
+stream_t *stream_create_from_fd(int fd);
+
+#endif /** STREAM_H_ @}*/