luc14n0/glib
1
0
Fork 0
mirror of https://gitlab.gnome.org/GNOME/glib.git synced 2024-11-06 17:36:14 +01:00
Code Issues Packages Projects Releases Wiki Activity
c320bb0bf8
glib/gio/gunixoutputstream.c
Philip Withnall 434d3ff524 docs: Mention GioUnix-2.0 GIR namespace alongside gio-unix-2.0.pc 
This should clarify things a little for users of language bindings, who
don’t directly use `.pc` files.

Signed-off-by: Philip Withnall <pwithnall@gnome.org>
2024-02-12 17:54:10 +00:00

637 lines
17 KiB
C
Raw Blame History

/* GIO - GLib Input, Output and Streaming Library
*
* Copyright (C) 2006-2007 Red Hat, Inc.
*
* SPDX-License-Identifier: LGPL-2.1-or-later
*
* 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 2.1 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/>.
*
* Author: Alexander Larsson <alexl@redhat.com>
*/
#include "config.h"
#include <unistd.h>
#include <errno.h>
#include <stdio.h>
#include <sys/uio.h>
#include <glib.h>
#include <glib/gstdio.h>
#include <glib/glib-unix.h>
#include "gioerror.h"
#include "gunixoutputstream.h"
#include "gcancellable.h"
#include "gasynchelper.h"
#include "gfiledescriptorbased.h"
#include "glibintl.h"
#include "gioprivate.h"
#include "giounix-private.h"
/**
* GUnixOutputStream:
*
* `GUnixOutputStream` implements [class@Gio.OutputStream] for writing to a UNIX
* file descriptor, including asynchronous operations. (If the file
* descriptor refers to a socket or pipe, this will use `poll()` to do
* asynchronous I/O. If it refers to a regular file, it will fall back
* to doing asynchronous I/O in another thread.)
*
* Note that `<gio/gunixoutputstream.h>` belongs to the UNIX-specific GIO
* interfaces, thus you have to use the `gio-unix-2.0.pc` pkg-config file
* file or the `GioUnix-2.0` GIR namespace when using it.
*/
enum {
PROP_0,
PROP_FD,
PROP_CLOSE_FD
};
struct _GUnixOutputStreamPrivate {
int fd;
guint close_fd : 1;
guint can_poll : 1;
};
static void g_unix_output_stream_pollable_iface_init (GPollableOutputStreamInterface *iface);
static void g_unix_output_stream_file_descriptor_based_iface_init (GFileDescriptorBasedIface *iface);
G_DEFINE_TYPE_WITH_CODE (GUnixOutputStream, g_unix_output_stream, G_TYPE_OUTPUT_STREAM,
G_ADD_PRIVATE (GUnixOutputStream)
G_IMPLEMENT_INTERFACE (G_TYPE_POLLABLE_OUTPUT_STREAM,
g_unix_output_stream_pollable_iface_init)
G_IMPLEMENT_INTERFACE (G_TYPE_FILE_DESCRIPTOR_BASED,
g_unix_output_stream_file_descriptor_based_iface_init)
)
static void g_unix_output_stream_set_property (GObject *object,
guint prop_id,
const GValue *value,
GParamSpec *pspec);
static void g_unix_output_stream_get_property (GObject *object,
guint prop_id,
GValue *value,
GParamSpec *pspec);
static gssize g_unix_output_stream_write (GOutputStream *stream,
const void *buffer,
gsize count,
GCancellable *cancellable,
GError **error);
static gboolean g_unix_output_stream_writev (GOutputStream *stream,
const GOutputVector *vectors,
gsize n_vectors,
gsize *bytes_written,
GCancellable *cancellable,
GError **error);
static gboolean g_unix_output_stream_close (GOutputStream *stream,
GCancellable *cancellable,
GError **error);
static gboolean g_unix_output_stream_pollable_can_poll (GPollableOutputStream *stream);
static gboolean g_unix_output_stream_pollable_is_writable (GPollableOutputStream *stream);
static GSource *g_unix_output_stream_pollable_create_source (GPollableOutputStream *stream,
GCancellable *cancellable);
static GPollableReturn g_unix_output_stream_pollable_writev_nonblocking (GPollableOutputStream *stream,
const GOutputVector *vectors,
gsize n_vectors,
gsize *bytes_written,
GError **error);
static void
g_unix_output_stream_class_init (GUnixOutputStreamClass *klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
GOutputStreamClass *stream_class = G_OUTPUT_STREAM_CLASS (klass);
gobject_class->get_property = g_unix_output_stream_get_property;
gobject_class->set_property = g_unix_output_stream_set_property;
stream_class->write_fn = g_unix_output_stream_write;
stream_class->writev_fn = g_unix_output_stream_writev;
stream_class->close_fn = g_unix_output_stream_close;
/**
* GUnixOutputStream:fd:
*
* The file descriptor that the stream writes to.
*
* Since: 2.20
*/
g_object_class_install_property (gobject_class,
PROP_FD,
g_param_spec_int ("fd", NULL, NULL,
G_MININT, G_MAXINT, -1,
G_PARAM_READABLE | G_PARAM_WRITABLE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_NAME | G_PARAM_STATIC_NICK | G_PARAM_STATIC_BLURB));
/**
* GUnixOutputStream:close-fd:
*
* Whether to close the file descriptor when the stream is closed.
*
* Since: 2.20
*/
g_object_class_install_property (gobject_class,
PROP_CLOSE_FD,
g_param_spec_boolean ("close-fd", NULL, NULL,
TRUE,
G_PARAM_READABLE | G_PARAM_WRITABLE | G_PARAM_STATIC_NAME | G_PARAM_STATIC_NICK | G_PARAM_STATIC_BLURB));
}
static void
g_unix_output_stream_pollable_iface_init (GPollableOutputStreamInterface *iface)
{
iface->can_poll = g_unix_output_stream_pollable_can_poll;
iface->is_writable = g_unix_output_stream_pollable_is_writable;
iface->create_source = g_unix_output_stream_pollable_create_source;
iface->writev_nonblocking = g_unix_output_stream_pollable_writev_nonblocking;
}
static void
g_unix_output_stream_file_descriptor_based_iface_init (GFileDescriptorBasedIface *iface)
{
iface->get_fd = (int (*) (GFileDescriptorBased *))g_unix_output_stream_get_fd;
}
static void
g_unix_output_stream_set_property (GObject *object,
guint prop_id,
const GValue *value,
GParamSpec *pspec)
{
GUnixOutputStream *unix_stream;
unix_stream = G_UNIX_OUTPUT_STREAM (object);
switch (prop_id)
{
case PROP_FD:
unix_stream->priv->fd = g_value_get_int (value);
unix_stream->priv->can_poll = _g_fd_is_pollable (unix_stream->priv->fd);
break;
case PROP_CLOSE_FD:
unix_stream->priv->close_fd = g_value_get_boolean (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
g_unix_output_stream_get_property (GObject *object,
guint prop_id,
GValue *value,
GParamSpec *pspec)
{
GUnixOutputStream *unix_stream;
unix_stream = G_UNIX_OUTPUT_STREAM (object);
switch (prop_id)
{
case PROP_FD:
g_value_set_int (value, unix_stream->priv->fd);
break;
case PROP_CLOSE_FD:
g_value_set_boolean (value, unix_stream->priv->close_fd);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
}
}
static void
g_unix_output_stream_init (GUnixOutputStream *unix_stream)
{
unix_stream->priv = g_unix_output_stream_get_instance_private (unix_stream);
unix_stream->priv->fd = -1;
unix_stream->priv->close_fd = TRUE;
}
/**
* g_unix_output_stream_new:
* @fd: a UNIX file descriptor
* @close_fd: %TRUE to close the file descriptor when done
*
* Creates a new #GUnixOutputStream for the given @fd.
*
* If @close_fd, is %TRUE, the file descriptor will be closed when
* the output stream is destroyed.
*
* Returns: a new #GOutputStream
**/
GOutputStream *
g_unix_output_stream_new (gint fd,
gboolean close_fd)
{
GUnixOutputStream *stream;
g_return_val_if_fail (fd != -1, NULL);
stream = g_object_new (G_TYPE_UNIX_OUTPUT_STREAM,
"fd", fd,
"close-fd", close_fd,
NULL);
return G_OUTPUT_STREAM (stream);
}
/**
* g_unix_output_stream_set_close_fd:
* @stream: a #GUnixOutputStream
* @close_fd: %TRUE to close the file descriptor when done
*
* Sets whether the file descriptor of @stream shall be closed
* when the stream is closed.
*
* Since: 2.20
*/
void
g_unix_output_stream_set_close_fd (GUnixOutputStream *stream,
gboolean close_fd)
{
g_return_if_fail (G_IS_UNIX_OUTPUT_STREAM (stream));
close_fd = close_fd != FALSE;
if (stream->priv->close_fd != close_fd)
{
stream->priv->close_fd = close_fd;
g_object_notify (G_OBJECT (stream), "close-fd");
}
}
/**
* g_unix_output_stream_get_close_fd:
* @stream: a #GUnixOutputStream
*
* Returns whether the file descriptor of @stream will be
* closed when the stream is closed.
*
* Returns: %TRUE if the file descriptor is closed when done
*
* Since: 2.20
*/
gboolean
g_unix_output_stream_get_close_fd (GUnixOutputStream *stream)
{
g_return_val_if_fail (G_IS_UNIX_OUTPUT_STREAM (stream), FALSE);
return stream->priv->close_fd;
}
/**
* g_unix_output_stream_get_fd:
* @stream: a #GUnixOutputStream
*
* Return the UNIX file descriptor that the stream writes to.
*
* Returns: The file descriptor of @stream
*
* Since: 2.20
*/
gint
g_unix_output_stream_get_fd (GUnixOutputStream *stream)
{
g_return_val_if_fail (G_IS_UNIX_OUTPUT_STREAM (stream), -1);
return stream->priv->fd;
}
static gssize
g_unix_output_stream_write (GOutputStream *stream,
const void *buffer,
gsize count,
GCancellable *cancellable,
GError **error)
{
GUnixOutputStream *unix_stream;
gssize res = -1;
GPollFD poll_fds[2];
int nfds = 0;
int poll_ret;
unix_stream = G_UNIX_OUTPUT_STREAM (stream);
poll_fds[0].fd = unix_stream->priv->fd;
poll_fds[0].events = G_IO_OUT;
nfds++;
if (unix_stream->priv->can_poll &&
g_cancellable_make_pollfd (cancellable, &poll_fds[1]))
nfds++;
while (1)
{
int errsv;
poll_fds[0].revents = poll_fds[1].revents = 0;
do
{
poll_ret = g_poll (poll_fds, nfds, -1);
errsv = errno;
}
while (poll_ret == -1 && errsv == EINTR);
if (poll_ret == -1)
{
g_set_error (error, G_IO_ERROR,
g_io_error_from_errno (errsv),
_("Error writing to file descriptor: %s"),
g_strerror (errsv));
break;
}
if (g_cancellable_set_error_if_cancelled (cancellable, error))
break;
if (!poll_fds[0].revents)
continue;
res = write (unix_stream->priv->fd, buffer, count);
errsv = errno;
if (res == -1)
{
if (errsv == EINTR || errsv == EAGAIN)
continue;
g_set_error (error, G_IO_ERROR,
g_io_error_from_errno (errsv),
_("Error writing to file descriptor: %s"),
g_strerror (errsv));
}
break;
}
if (nfds == 2)
g_cancellable_release_fd (cancellable);
return res;
}
/* Macro to check if struct iovec and GOutputVector have the same ABI */
#define G_OUTPUT_VECTOR_IS_IOVEC (sizeof (struct iovec) == sizeof (GOutputVector) && \
G_SIZEOF_MEMBER (struct iovec, iov_base) == G_SIZEOF_MEMBER (GOutputVector, buffer) && \
G_STRUCT_OFFSET (struct iovec, iov_base) == G_STRUCT_OFFSET (GOutputVector, buffer) && \
G_SIZEOF_MEMBER (struct iovec, iov_len) == G_SIZEOF_MEMBER (GOutputVector, size) && \
G_STRUCT_OFFSET (struct iovec, iov_len) == G_STRUCT_OFFSET (GOutputVector, size))
static gboolean
g_unix_output_stream_writev (GOutputStream *stream,
const GOutputVector *vectors,
gsize n_vectors,
gsize *bytes_written,
GCancellable *cancellable,
GError **error)
{
GUnixOutputStream *unix_stream;
gssize res = -1;
GPollFD poll_fds[2];
int nfds = 0;
int poll_ret;
struct iovec *iov;
if (bytes_written)
*bytes_written = 0;
/* Clamp the number of vectors if more given than we can write in one go.
* The caller has to handle short writes anyway.
*/
if (n_vectors > G_IOV_MAX)
n_vectors = G_IOV_MAX;
unix_stream = G_UNIX_OUTPUT_STREAM (stream);
if (G_OUTPUT_VECTOR_IS_IOVEC)
{
/* ABI is compatible */
iov = (struct iovec *) vectors;
}
else
{
gsize i;
/* ABI is incompatible */
iov = g_newa (struct iovec, n_vectors);
for (i = 0; i < n_vectors; i++)
{
iov[i].iov_base = (void *)vectors[i].buffer;
iov[i].iov_len = vectors[i].size;
}
}
poll_fds[0].fd = unix_stream->priv->fd;
poll_fds[0].events = G_IO_OUT;
nfds++;
if (unix_stream->priv->can_poll &&
g_cancellable_make_pollfd (cancellable, &poll_fds[1]))
nfds++;
while (1)
{
int errsv;
poll_fds[0].revents = poll_fds[1].revents = 0;
do
{
poll_ret = g_poll (poll_fds, nfds, -1);
errsv = errno;
}
while (poll_ret == -1 && errsv == EINTR);
if (poll_ret == -1)
{
g_set_error (error, G_IO_ERROR,
g_io_error_from_errno (errsv),
_("Error writing to file descriptor: %s"),
g_strerror (errsv));
break;
}
if (g_cancellable_set_error_if_cancelled (cancellable, error))
break;
if (!poll_fds[0].revents)
continue;
res = writev (unix_stream->priv->fd, iov, n_vectors);
errsv = errno;
if (res == -1)
{
if (errsv == EINTR || errsv == EAGAIN)
continue;
g_set_error (error, G_IO_ERROR,
g_io_error_from_errno (errsv),
_("Error writing to file descriptor: %s"),
g_strerror (errsv));
}
if (bytes_written)
*bytes_written = res;
break;
}
if (nfds == 2)
g_cancellable_release_fd (cancellable);
return res != -1;
}
static gboolean
g_unix_output_stream_close (GOutputStream *stream,
GCancellable *cancellable,
GError **error)
{
GUnixOutputStream *unix_stream;
int res;
unix_stream = G_UNIX_OUTPUT_STREAM (stream);
if (!unix_stream->priv->close_fd)
return TRUE;
/* This might block during the close. Doesn't seem to be a way to avoid it though. */
res = close (unix_stream->priv->fd);
if (res == -1)
{
int errsv = errno;
g_set_error (error, G_IO_ERROR,
g_io_error_from_errno (errsv),
_("Error closing file descriptor: %s"),
g_strerror (errsv));
}
return res != -1;
}
static gboolean
g_unix_output_stream_pollable_can_poll (GPollableOutputStream *stream)
{
return G_UNIX_OUTPUT_STREAM (stream)->priv->can_poll;
}
static gboolean
g_unix_output_stream_pollable_is_writable (GPollableOutputStream *stream)
{
GUnixOutputStream *unix_stream = G_UNIX_OUTPUT_STREAM (stream);
GPollFD poll_fd;
gint result;
poll_fd.fd = unix_stream->priv->fd;
poll_fd.events = G_IO_OUT;
poll_fd.revents = 0;
do
result = g_poll (&poll_fd, 1, 0);
while (result == -1 && errno == EINTR);
return poll_fd.revents != 0;
}
static GSource *
g_unix_output_stream_pollable_create_source (GPollableOutputStream *stream,
GCancellable *cancellable)
{
GUnixOutputStream *unix_stream = G_UNIX_OUTPUT_STREAM (stream);
GSource *inner_source, *cancellable_source, *pollable_source;
pollable_source = g_pollable_source_new (G_OBJECT (stream));
inner_source = g_unix_fd_source_new (unix_stream->priv->fd, G_IO_OUT);
g_source_set_dummy_callback (inner_source);
g_source_add_child_source (pollable_source, inner_source);
g_source_unref (inner_source);
if (cancellable)
{
cancellable_source = g_cancellable_source_new (cancellable);
g_source_set_dummy_callback (cancellable_source);
g_source_add_child_source (pollable_source, cancellable_source);
g_source_unref (cancellable_source);
}
return pollable_source;
}
static GPollableReturn
g_unix_output_stream_pollable_writev_nonblocking (GPollableOutputStream *stream,
const GOutputVector *vectors,
gsize n_vectors,
gsize *bytes_written,
GError **error)
{
GUnixOutputStream *unix_stream = G_UNIX_OUTPUT_STREAM (stream);
struct iovec *iov;
gssize res = -1;
if (!g_pollable_output_stream_is_writable (stream))
{
*bytes_written = 0;
return G_POLLABLE_RETURN_WOULD_BLOCK;
}
/* Clamp the number of vectors if more given than we can write in one go.
* The caller has to handle short writes anyway.
*/
if (n_vectors > G_IOV_MAX)
n_vectors = G_IOV_MAX;
if (G_OUTPUT_VECTOR_IS_IOVEC)
{
/* ABI is compatible */
iov = (struct iovec *) vectors;
}
else
{
gsize i;
/* ABI is incompatible */
iov = g_newa (struct iovec, n_vectors);
for (i = 0; i < n_vectors; i++)
{
iov[i].iov_base = (void *)vectors[i].buffer;
iov[i].iov_len = vectors[i].size;
}
}
while (1)
{
int errsv;
res = writev (unix_stream->priv->fd, iov, n_vectors);
errsv = errno;
if (res == -1)
{
if (errsv == EINTR)
continue;
g_set_error (error, G_IO_ERROR,
g_io_error_from_errno (errsv),
_("Error writing to file descriptor: %s"),
g_strerror (errsv));
}
if (bytes_written)
*bytes_written = res;
break;
}
return res != -1 ? G_POLLABLE_RETURN_OK : G_POLLABLE_RETURN_FAILED;
}
Reference in New Issue View Git Blame Copy Permalink