Commit c767ae62 authored by Daniel P. Berrangé's avatar Daniel P. Berrangé
Browse files

io: introduce helper for creating channels from file descriptors 



Depending on what object a file descriptor refers to a different
type of IO channel will be needed - either a QIOChannelFile or
a QIOChannelSocket. Introduce a qio_channel_new_fd() method
which will return the appropriate channel implementation.

Reviewed-by: default avatarEric Blake <eblake@redhat.com>
Signed-off-by: default avatarDaniel P. Berrange <berrange@redhat.com>
parent fe81e932

include/io/channel-util.h

0 → 100644
+52 −0
Original line number Diff line number Diff line 
/*

 * QEMU I/O channels utility APIs

 *

 * Copyright (c) 2016 Red Hat, Inc.

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * This library 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, see <http://www.gnu.org/licenses/>.

 *

 */



#ifndef QIO_CHANNEL_UTIL_H__

#define QIO_CHANNEL_UTIL_H__



#include "io/channel.h"



/*

 * This module provides helper functions that are useful when dealing

 * with QIOChannel objects

 */





/**

 * qio_channel_new_fd:

 * @fd: the file descriptor

 * @errp: pointer to a NULL-initialized error object

 *

 * Create a channel for performing I/O on the file

 * descriptor @fd. The particular subclass of QIOChannel

 * that is returned will depend on what underlying object

 * the file descriptor is associated with. It may be either

 * a QIOChannelSocket or a QIOChannelFile instance. Upon

 * success, the returned QIOChannel instance will own

 * the @fd file descriptor, and take responsibility for

 * closing it when no longer required. On failure, the

 * caller is responsible for closing @fd.

 *

 * Returns: the channel object, or NULL on error

 */

QIOChannel *qio_channel_new_fd(int fd,

                               Error **errp);



#endif /* QIO_CHANNEL_UTIL_H__ */

io/Makefile.objs

+1 −0
Original line number Diff line number Diff line
@@ -6,4 +6,5 @@ io-obj-y += channel-socket.o 
io-obj-y += channel-tls.o

io-obj-y += channel-watch.o

io-obj-y += channel-websock.o

io-obj-y += channel-util.o

io-obj-y += task.o

io/channel-util.c

0 → 100644
+50 −0
Original line number Diff line number Diff line 
/*

 * QEMU I/O channels utility APIs

 *

 * Copyright (c) 2016 Red Hat, Inc.

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * This library 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, see <http://www.gnu.org/licenses/>.

 *

 */



#include "io/channel-util.h"

#include "io/channel-file.h"

#include "io/channel-socket.h"





static bool fd_is_socket(int fd)

{

    int optval;

    socklen_t optlen;

    optlen = sizeof(optval);

    return qemu_getsockopt(fd,

                           SOL_SOCKET,

                           SO_TYPE,

                           (char *)&optval,

                           &optlen) == 0;

}





QIOChannel *qio_channel_new_fd(int fd,

                               Error **errp)

{

    QIOChannel *ioc;



    if (fd_is_socket(fd)) {

        ioc = QIO_CHANNEL(qio_channel_socket_new_fd(fd, errp));

    } else {

        ioc = QIO_CHANNEL(qio_channel_file_new_fd(fd));

    }

    return ioc;

}

tests/test-io-channel-file.c

+22 −0
Original line number Diff line number Diff line
@@ -19,6 +19,7 @@ 
 */



#include "io/channel-file.h"

#include "io/channel-util.h"

#include "io-channel-helpers.h"
@@ -49,6 +50,26 @@ static void test_io_channel_file(void) 
}





static void test_io_channel_fd(void)

{

    QIOChannel *ioc;

    int fd = -1;



#define TEST_FILE "tests/test-io-channel-file.txt"

    fd = open(TEST_FILE, O_CREAT | O_TRUNC | O_WRONLY, 0600);

    g_assert_cmpint(fd, >, -1);



    ioc = qio_channel_new_fd(fd, &error_abort);



    g_assert_cmpstr(object_get_typename(OBJECT(ioc)),

                    ==,

                    TYPE_QIO_CHANNEL_FILE);



    unlink(TEST_FILE);

    object_unref(OBJECT(ioc));

}





#ifndef _WIN32

static void test_io_channel_pipe(bool async)

{
@@ -92,6 +113,7 @@ int main(int argc, char **argv) 
    g_test_init(&argc, &argv, NULL);



    g_test_add_func("/io/channel/file", test_io_channel_file);

    g_test_add_func("/io/channel/file/fd", test_io_channel_fd);

#ifndef _WIN32

    g_test_add_func("/io/channel/pipe/sync", test_io_channel_pipe_sync);

    g_test_add_func("/io/channel/pipe/async", test_io_channel_pipe_async);

tests/test-io-channel-socket.c

+21 −0
Original line number Diff line number Diff line
@@ -19,6 +19,7 @@ 
 */



#include "io/channel-socket.h"

#include "io/channel-util.h"

#include "io-channel-helpers.h"

#ifdef HAVE_IFADDRS_H

#include <ifaddrs.h>
@@ -473,6 +474,24 @@ static void test_io_channel_unix_fd_pass(void) 
#endif /* _WIN32 */





static void test_io_channel_ipv4_fd(void)

{

    QIOChannel *ioc;

    int fd = -1;



    fd = socket(AF_INET, SOCK_STREAM, 0);

    g_assert_cmpint(fd, >, -1);



    ioc = qio_channel_new_fd(fd, &error_abort);



    g_assert_cmpstr(object_get_typename(OBJECT(ioc)),

                    ==,

                    TYPE_QIO_CHANNEL_SOCKET);



    object_unref(OBJECT(ioc));

}





int main(int argc, char **argv)

{

    bool has_ipv4, has_ipv6;
@@ -495,6 +514,8 @@ int main(int argc, char **argv) 
                        test_io_channel_ipv4_sync);

        g_test_add_func("/io/channel/socket/ipv4-async",

                        test_io_channel_ipv4_async);

        g_test_add_func("/io/channel/socket/ipv4-fd",

                        test_io_channel_ipv4_fd);

    }

    if (has_ipv6) {

        g_test_add_func("/io/channel/socket/ipv6-sync",