a8d2532645
No header includes qemu-common.h after this commit, as prescribed by qemu-common.h's file comment. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20190523143508.25387-5-armbru@redhat.com> [Rebased with conflicts resolved automatically, except for include/hw/arm/xlnx-zynqmp.h hw/arm/nrf51_soc.c hw/arm/msf2-soc.c block/qcow2-refcount.c block/qcow2-cluster.c block/qcow2-cache.c target/arm/cpu.h target/lm32/cpu.h target/m68k/cpu.h target/mips/cpu.h target/moxie/cpu.h target/nios2/cpu.h target/openrisc/cpu.h target/riscv/cpu.h target/tilegx/cpu.h target/tricore/cpu.h target/unicore32/cpu.h target/xtensa/cpu.h; bsd-user/main.c and net/tap-bsd.c fixed up]
784 lines
26 KiB
C
784 lines
26 KiB
C
/*
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* QEMU I/O channels
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*
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* Copyright (c) 2015 Red Hat, Inc.
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, see <http://www.gnu.org/licenses/>.
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*
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*/
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#ifndef QIO_CHANNEL_H
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#define QIO_CHANNEL_H
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#include "qom/object.h"
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#include "qemu/coroutine.h"
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#include "block/aio.h"
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#define TYPE_QIO_CHANNEL "qio-channel"
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#define QIO_CHANNEL(obj) \
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OBJECT_CHECK(QIOChannel, (obj), TYPE_QIO_CHANNEL)
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#define QIO_CHANNEL_CLASS(klass) \
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OBJECT_CLASS_CHECK(QIOChannelClass, klass, TYPE_QIO_CHANNEL)
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#define QIO_CHANNEL_GET_CLASS(obj) \
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OBJECT_GET_CLASS(QIOChannelClass, obj, TYPE_QIO_CHANNEL)
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typedef struct QIOChannel QIOChannel;
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typedef struct QIOChannelClass QIOChannelClass;
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#define QIO_CHANNEL_ERR_BLOCK -2
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typedef enum QIOChannelFeature QIOChannelFeature;
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enum QIOChannelFeature {
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QIO_CHANNEL_FEATURE_FD_PASS,
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QIO_CHANNEL_FEATURE_SHUTDOWN,
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QIO_CHANNEL_FEATURE_LISTEN,
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};
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typedef enum QIOChannelShutdown QIOChannelShutdown;
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enum QIOChannelShutdown {
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QIO_CHANNEL_SHUTDOWN_READ = 1,
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QIO_CHANNEL_SHUTDOWN_WRITE = 2,
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QIO_CHANNEL_SHUTDOWN_BOTH = 3,
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};
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typedef gboolean (*QIOChannelFunc)(QIOChannel *ioc,
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GIOCondition condition,
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gpointer data);
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/**
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* QIOChannel:
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*
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* The QIOChannel defines the core API for a generic I/O channel
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* class hierarchy. It is inspired by GIOChannel, but has the
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* following differences
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*
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* - Use QOM to properly support arbitrary subclassing
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* - Support use of iovecs for efficient I/O with multiple blocks
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* - None of the character set translation, binary data exclusively
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* - Direct support for QEMU Error object reporting
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* - File descriptor passing
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*
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* This base class is abstract so cannot be instantiated. There
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* will be subclasses for dealing with sockets, files, and higher
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* level protocols such as TLS, WebSocket, etc.
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*/
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struct QIOChannel {
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Object parent;
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unsigned int features; /* bitmask of QIOChannelFeatures */
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char *name;
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AioContext *ctx;
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Coroutine *read_coroutine;
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Coroutine *write_coroutine;
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#ifdef _WIN32
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HANDLE event; /* For use with GSource on Win32 */
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#endif
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};
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/**
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* QIOChannelClass:
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*
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* This class defines the contract that all subclasses
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* must follow to provide specific channel implementations.
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* The first five callbacks are mandatory to support, others
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* provide additional optional features.
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*
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* Consult the corresponding public API docs for a description
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* of the semantics of each callback
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*/
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struct QIOChannelClass {
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ObjectClass parent;
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/* Mandatory callbacks */
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ssize_t (*io_writev)(QIOChannel *ioc,
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const struct iovec *iov,
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size_t niov,
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int *fds,
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size_t nfds,
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Error **errp);
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ssize_t (*io_readv)(QIOChannel *ioc,
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const struct iovec *iov,
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size_t niov,
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int **fds,
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size_t *nfds,
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Error **errp);
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int (*io_close)(QIOChannel *ioc,
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Error **errp);
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GSource * (*io_create_watch)(QIOChannel *ioc,
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GIOCondition condition);
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int (*io_set_blocking)(QIOChannel *ioc,
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bool enabled,
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Error **errp);
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/* Optional callbacks */
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int (*io_shutdown)(QIOChannel *ioc,
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QIOChannelShutdown how,
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Error **errp);
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void (*io_set_cork)(QIOChannel *ioc,
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bool enabled);
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void (*io_set_delay)(QIOChannel *ioc,
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bool enabled);
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off_t (*io_seek)(QIOChannel *ioc,
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off_t offset,
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int whence,
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Error **errp);
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void (*io_set_aio_fd_handler)(QIOChannel *ioc,
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AioContext *ctx,
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IOHandler *io_read,
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IOHandler *io_write,
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void *opaque);
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};
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/* General I/O handling functions */
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/**
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* qio_channel_has_feature:
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* @ioc: the channel object
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* @feature: the feature to check support of
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*
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* Determine whether the channel implementation supports
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* the optional feature named in @feature.
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*
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* Returns: true if supported, false otherwise.
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*/
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bool qio_channel_has_feature(QIOChannel *ioc,
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QIOChannelFeature feature);
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/**
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* qio_channel_set_feature:
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* @ioc: the channel object
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* @feature: the feature to set support for
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*
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* Add channel support for the feature named in @feature.
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*/
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void qio_channel_set_feature(QIOChannel *ioc,
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QIOChannelFeature feature);
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/**
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* qio_channel_set_name:
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* @ioc: the channel object
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* @name: the name of the channel
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*
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* Sets the name of the channel, which serves as an aid
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* to debugging. The name is used when creating GSource
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* watches for this channel.
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*/
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void qio_channel_set_name(QIOChannel *ioc,
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const char *name);
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/**
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* qio_channel_readv_full:
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* @ioc: the channel object
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* @iov: the array of memory regions to read data into
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* @niov: the length of the @iov array
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* @fds: pointer to an array that will received file handles
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* @nfds: pointer filled with number of elements in @fds on return
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* @errp: pointer to a NULL-initialized error object
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*
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* Read data from the IO channel, storing it in the
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* memory regions referenced by @iov. Each element
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* in the @iov will be fully populated with data
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* before the next one is used. The @niov parameter
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* specifies the total number of elements in @iov.
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*
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* It is not required for all @iov to be filled with
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* data. If the channel is in blocking mode, at least
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* one byte of data will be read, but no more is
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* guaranteed. If the channel is non-blocking and no
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* data is available, it will return QIO_CHANNEL_ERR_BLOCK
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*
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* If the channel has passed any file descriptors,
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* the @fds array pointer will be allocated and
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* the elements filled with the received file
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* descriptors. The @nfds pointer will be updated
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* to indicate the size of the @fds array that
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* was allocated. It is the callers responsibility
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* to call close() on each file descriptor and to
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* call g_free() on the array pointer in @fds.
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*
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* It is an error to pass a non-NULL @fds parameter
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* unless qio_channel_has_feature() returns a true
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* value for the QIO_CHANNEL_FEATURE_FD_PASS constant.
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*
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* Returns: the number of bytes read, or -1 on error,
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* or QIO_CHANNEL_ERR_BLOCK if no data is available
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* and the channel is non-blocking
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*/
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ssize_t qio_channel_readv_full(QIOChannel *ioc,
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const struct iovec *iov,
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size_t niov,
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int **fds,
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size_t *nfds,
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Error **errp);
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/**
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* qio_channel_writev_full:
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* @ioc: the channel object
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* @iov: the array of memory regions to write data from
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* @niov: the length of the @iov array
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* @fds: an array of file handles to send
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* @nfds: number of file handles in @fds
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* @errp: pointer to a NULL-initialized error object
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*
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* Write data to the IO channel, reading it from the
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* memory regions referenced by @iov. Each element
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* in the @iov will be fully sent, before the next
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* one is used. The @niov parameter specifies the
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* total number of elements in @iov.
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*
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* It is not required for all @iov data to be fully
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* sent. If the channel is in blocking mode, at least
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* one byte of data will be sent, but no more is
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* guaranteed. If the channel is non-blocking and no
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* data can be sent, it will return QIO_CHANNEL_ERR_BLOCK
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*
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* If there are file descriptors to send, the @fds
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* array should be non-NULL and provide the handles.
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* All file descriptors will be sent if at least one
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* byte of data was sent.
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*
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* It is an error to pass a non-NULL @fds parameter
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* unless qio_channel_has_feature() returns a true
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* value for the QIO_CHANNEL_FEATURE_FD_PASS constant.
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*
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* Returns: the number of bytes sent, or -1 on error,
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* or QIO_CHANNEL_ERR_BLOCK if no data is can be sent
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* and the channel is non-blocking
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*/
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ssize_t qio_channel_writev_full(QIOChannel *ioc,
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const struct iovec *iov,
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size_t niov,
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int *fds,
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size_t nfds,
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Error **errp);
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/**
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* qio_channel_readv_all_eof:
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* @ioc: the channel object
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* @iov: the array of memory regions to read data into
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* @niov: the length of the @iov array
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* @errp: pointer to a NULL-initialized error object
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*
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* Read data from the IO channel, storing it in the
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* memory regions referenced by @iov. Each element
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* in the @iov will be fully populated with data
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* before the next one is used. The @niov parameter
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* specifies the total number of elements in @iov.
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*
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* The function will wait for all requested data
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* to be read, yielding from the current coroutine
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* if required.
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*
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* If end-of-file occurs before any data is read,
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* no error is reported; otherwise, if it occurs
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* before all requested data has been read, an error
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* will be reported.
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*
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* Returns: 1 if all bytes were read, 0 if end-of-file
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* occurs without data, or -1 on error
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*/
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int qio_channel_readv_all_eof(QIOChannel *ioc,
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const struct iovec *iov,
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size_t niov,
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Error **errp);
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/**
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* qio_channel_readv_all:
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* @ioc: the channel object
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* @iov: the array of memory regions to read data into
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* @niov: the length of the @iov array
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* @errp: pointer to a NULL-initialized error object
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*
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* Read data from the IO channel, storing it in the
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* memory regions referenced by @iov. Each element
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* in the @iov will be fully populated with data
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* before the next one is used. The @niov parameter
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* specifies the total number of elements in @iov.
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*
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* The function will wait for all requested data
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* to be read, yielding from the current coroutine
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* if required.
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*
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* If end-of-file occurs before all requested data
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* has been read, an error will be reported.
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*
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* Returns: 0 if all bytes were read, or -1 on error
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*/
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int qio_channel_readv_all(QIOChannel *ioc,
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const struct iovec *iov,
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size_t niov,
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Error **errp);
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/**
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* qio_channel_writev_all:
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* @ioc: the channel object
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* @iov: the array of memory regions to write data from
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* @niov: the length of the @iov array
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* @errp: pointer to a NULL-initialized error object
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*
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* Write data to the IO channel, reading it from the
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* memory regions referenced by @iov. Each element
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* in the @iov will be fully sent, before the next
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* one is used. The @niov parameter specifies the
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* total number of elements in @iov.
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*
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* The function will wait for all requested data
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* to be written, yielding from the current coroutine
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* if required.
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*
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* Returns: 0 if all bytes were written, or -1 on error
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*/
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int qio_channel_writev_all(QIOChannel *ioc,
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const struct iovec *iov,
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size_t niov,
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Error **erp);
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/**
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* qio_channel_readv:
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* @ioc: the channel object
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* @iov: the array of memory regions to read data into
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* @niov: the length of the @iov array
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* @errp: pointer to a NULL-initialized error object
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*
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* Behaves as qio_channel_readv_full() but does not support
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* receiving of file handles.
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*/
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ssize_t qio_channel_readv(QIOChannel *ioc,
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const struct iovec *iov,
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size_t niov,
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Error **errp);
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/**
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* qio_channel_writev:
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* @ioc: the channel object
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* @iov: the array of memory regions to write data from
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* @niov: the length of the @iov array
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* @errp: pointer to a NULL-initialized error object
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*
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* Behaves as qio_channel_writev_full() but does not support
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* sending of file handles.
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*/
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ssize_t qio_channel_writev(QIOChannel *ioc,
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const struct iovec *iov,
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size_t niov,
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Error **errp);
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/**
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* qio_channel_read:
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* @ioc: the channel object
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* @buf: the memory region to read data into
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* @buflen: the length of @buf
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* @errp: pointer to a NULL-initialized error object
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*
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* Behaves as qio_channel_readv_full() but does not support
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* receiving of file handles, and only supports reading into
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* a single memory region.
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*/
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ssize_t qio_channel_read(QIOChannel *ioc,
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char *buf,
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size_t buflen,
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Error **errp);
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/**
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* qio_channel_write:
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* @ioc: the channel object
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* @buf: the memory regions to send data from
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* @buflen: the length of @buf
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* @errp: pointer to a NULL-initialized error object
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*
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* Behaves as qio_channel_writev_full() but does not support
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* sending of file handles, and only supports writing from a
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* single memory region.
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*/
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ssize_t qio_channel_write(QIOChannel *ioc,
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const char *buf,
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size_t buflen,
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Error **errp);
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/**
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* qio_channel_read_all_eof:
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* @ioc: the channel object
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* @buf: the memory region to read data into
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* @buflen: the number of bytes to @buf
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* @errp: pointer to a NULL-initialized error object
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*
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* Reads @buflen bytes into @buf, possibly blocking or (if the
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* channel is non-blocking) yielding from the current coroutine
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* multiple times until the entire content is read. If end-of-file
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* occurs immediately it is not an error, but if it occurs after
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* data has been read it will return an error rather than a
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* short-read. Otherwise behaves as qio_channel_read().
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*
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* Returns: 1 if all bytes were read, 0 if end-of-file occurs
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* without data, or -1 on error
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*/
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int qio_channel_read_all_eof(QIOChannel *ioc,
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char *buf,
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size_t buflen,
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Error **errp);
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/**
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* qio_channel_read_all:
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* @ioc: the channel object
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* @buf: the memory region to read data into
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* @buflen: the number of bytes to @buf
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* @errp: pointer to a NULL-initialized error object
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*
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* Reads @buflen bytes into @buf, possibly blocking or (if the
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* channel is non-blocking) yielding from the current coroutine
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* multiple times until the entire content is read. If end-of-file
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* occurs it will return an error rather than a short-read. Otherwise
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* behaves as qio_channel_read().
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*
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* Returns: 0 if all bytes were read, or -1 on error
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*/
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int qio_channel_read_all(QIOChannel *ioc,
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char *buf,
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size_t buflen,
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Error **errp);
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/**
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* qio_channel_write_all:
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* @ioc: the channel object
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* @buf: the memory region to write data into
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* @buflen: the number of bytes to @buf
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* @errp: pointer to a NULL-initialized error object
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*
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* Writes @buflen bytes from @buf, possibly blocking or (if the
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* channel is non-blocking) yielding from the current coroutine
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* multiple times until the entire content is written. Otherwise
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* behaves as qio_channel_write().
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*
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* Returns: 0 if all bytes were written, or -1 on error
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*/
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int qio_channel_write_all(QIOChannel *ioc,
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const char *buf,
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size_t buflen,
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Error **errp);
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/**
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* qio_channel_set_blocking:
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* @ioc: the channel object
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* @enabled: the blocking flag state
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* @errp: pointer to a NULL-initialized error object
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*
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* If @enabled is true, then the channel is put into
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* blocking mode, otherwise it will be non-blocking.
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*
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* In non-blocking mode, read/write operations may
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* return QIO_CHANNEL_ERR_BLOCK if they would otherwise
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* block on I/O
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*/
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int qio_channel_set_blocking(QIOChannel *ioc,
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|
bool enabled,
|
|
Error **errp);
|
|
|
|
/**
|
|
* qio_channel_close:
|
|
* @ioc: the channel object
|
|
* @errp: pointer to a NULL-initialized error object
|
|
*
|
|
* Close the channel, flushing any pending I/O
|
|
*
|
|
* Returns: 0 on success, -1 on error
|
|
*/
|
|
int qio_channel_close(QIOChannel *ioc,
|
|
Error **errp);
|
|
|
|
/**
|
|
* qio_channel_shutdown:
|
|
* @ioc: the channel object
|
|
* @how: the direction to shutdown
|
|
* @errp: pointer to a NULL-initialized error object
|
|
*
|
|
* Shutdowns transmission and/or receiving of data
|
|
* without closing the underlying transport.
|
|
*
|
|
* Not all implementations will support this facility,
|
|
* so may report an error. To avoid errors, the
|
|
* caller may check for the feature flag
|
|
* QIO_CHANNEL_FEATURE_SHUTDOWN prior to calling
|
|
* this method.
|
|
*
|
|
* Returns: 0 on success, -1 on error
|
|
*/
|
|
int qio_channel_shutdown(QIOChannel *ioc,
|
|
QIOChannelShutdown how,
|
|
Error **errp);
|
|
|
|
/**
|
|
* qio_channel_set_delay:
|
|
* @ioc: the channel object
|
|
* @enabled: the new flag state
|
|
*
|
|
* Controls whether the underlying transport is
|
|
* permitted to delay writes in order to merge
|
|
* small packets. If @enabled is true, then the
|
|
* writes may be delayed in order to opportunistically
|
|
* merge small packets into larger ones. If @enabled
|
|
* is false, writes are dispatched immediately with
|
|
* no delay.
|
|
*
|
|
* When @enabled is false, applications may wish to
|
|
* use the qio_channel_set_cork() method to explicitly
|
|
* control write merging.
|
|
*
|
|
* On channels which are backed by a socket, this
|
|
* API corresponds to the inverse of TCP_NODELAY flag,
|
|
* controlling whether the Nagle algorithm is active.
|
|
*
|
|
* This setting is merely a hint, so implementations are
|
|
* free to ignore this without it being considered an
|
|
* error.
|
|
*/
|
|
void qio_channel_set_delay(QIOChannel *ioc,
|
|
bool enabled);
|
|
|
|
/**
|
|
* qio_channel_set_cork:
|
|
* @ioc: the channel object
|
|
* @enabled: the new flag state
|
|
*
|
|
* Controls whether the underlying transport is
|
|
* permitted to dispatch data that is written.
|
|
* If @enabled is true, then any data written will
|
|
* be queued in local buffers until @enabled is
|
|
* set to false once again.
|
|
*
|
|
* This feature is typically used when the automatic
|
|
* write coalescing facility is disabled via the
|
|
* qio_channel_set_delay() method.
|
|
*
|
|
* On channels which are backed by a socket, this
|
|
* API corresponds to the TCP_CORK flag.
|
|
*
|
|
* This setting is merely a hint, so implementations are
|
|
* free to ignore this without it being considered an
|
|
* error.
|
|
*/
|
|
void qio_channel_set_cork(QIOChannel *ioc,
|
|
bool enabled);
|
|
|
|
|
|
/**
|
|
* qio_channel_seek:
|
|
* @ioc: the channel object
|
|
* @offset: the position to seek to, relative to @whence
|
|
* @whence: one of the (POSIX) SEEK_* constants listed below
|
|
* @errp: pointer to a NULL-initialized error object
|
|
*
|
|
* Moves the current I/O position within the channel
|
|
* @ioc, to be @offset. The value of @offset is
|
|
* interpreted relative to @whence:
|
|
*
|
|
* SEEK_SET - the position is set to @offset bytes
|
|
* SEEK_CUR - the position is moved by @offset bytes
|
|
* SEEK_END - the position is set to end of the file plus @offset bytes
|
|
*
|
|
* Not all implementations will support this facility,
|
|
* so may report an error.
|
|
*
|
|
* Returns: the new position on success, (off_t)-1 on failure
|
|
*/
|
|
off_t qio_channel_io_seek(QIOChannel *ioc,
|
|
off_t offset,
|
|
int whence,
|
|
Error **errp);
|
|
|
|
|
|
/**
|
|
* qio_channel_create_watch:
|
|
* @ioc: the channel object
|
|
* @condition: the I/O condition to monitor
|
|
*
|
|
* Create a new main loop source that is used to watch
|
|
* for the I/O condition @condition. Typically the
|
|
* qio_channel_add_watch() method would be used instead
|
|
* of this, since it directly attaches a callback to
|
|
* the source
|
|
*
|
|
* Returns: the new main loop source.
|
|
*/
|
|
GSource *qio_channel_create_watch(QIOChannel *ioc,
|
|
GIOCondition condition);
|
|
|
|
/**
|
|
* qio_channel_add_watch:
|
|
* @ioc: the channel object
|
|
* @condition: the I/O condition to monitor
|
|
* @func: callback to invoke when the source becomes ready
|
|
* @user_data: opaque data to pass to @func
|
|
* @notify: callback to free @user_data
|
|
*
|
|
* Create a new main loop source that is used to watch
|
|
* for the I/O condition @condition. The callback @func
|
|
* will be registered against the source, to be invoked
|
|
* when the source becomes ready. The optional @user_data
|
|
* will be passed to @func when it is invoked. The @notify
|
|
* callback will be used to free @user_data when the
|
|
* watch is deleted
|
|
*
|
|
* The returned source ID can be used with g_source_remove()
|
|
* to remove and free the source when no longer required.
|
|
* Alternatively the @func callback can return a FALSE
|
|
* value.
|
|
*
|
|
* Returns: the source ID
|
|
*/
|
|
guint qio_channel_add_watch(QIOChannel *ioc,
|
|
GIOCondition condition,
|
|
QIOChannelFunc func,
|
|
gpointer user_data,
|
|
GDestroyNotify notify);
|
|
|
|
/**
|
|
* qio_channel_add_watch_full:
|
|
* @ioc: the channel object
|
|
* @condition: the I/O condition to monitor
|
|
* @func: callback to invoke when the source becomes ready
|
|
* @user_data: opaque data to pass to @func
|
|
* @notify: callback to free @user_data
|
|
* @context: the context to run the watch source
|
|
*
|
|
* Similar as qio_channel_add_watch(), but allows to specify context
|
|
* to run the watch source.
|
|
*
|
|
* Returns: the source ID
|
|
*/
|
|
guint qio_channel_add_watch_full(QIOChannel *ioc,
|
|
GIOCondition condition,
|
|
QIOChannelFunc func,
|
|
gpointer user_data,
|
|
GDestroyNotify notify,
|
|
GMainContext *context);
|
|
|
|
/**
|
|
* qio_channel_add_watch_source:
|
|
* @ioc: the channel object
|
|
* @condition: the I/O condition to monitor
|
|
* @func: callback to invoke when the source becomes ready
|
|
* @user_data: opaque data to pass to @func
|
|
* @notify: callback to free @user_data
|
|
* @context: gcontext to bind the source to
|
|
*
|
|
* Similar as qio_channel_add_watch(), but allows to specify context
|
|
* to run the watch source, meanwhile return the GSource object
|
|
* instead of tag ID, with the GSource referenced already.
|
|
*
|
|
* Note: callers is responsible to unref the source when not needed.
|
|
*
|
|
* Returns: the source pointer
|
|
*/
|
|
GSource *qio_channel_add_watch_source(QIOChannel *ioc,
|
|
GIOCondition condition,
|
|
QIOChannelFunc func,
|
|
gpointer user_data,
|
|
GDestroyNotify notify,
|
|
GMainContext *context);
|
|
|
|
/**
|
|
* qio_channel_attach_aio_context:
|
|
* @ioc: the channel object
|
|
* @ctx: the #AioContext to set the handlers on
|
|
*
|
|
* Request that qio_channel_yield() sets I/O handlers on
|
|
* the given #AioContext. If @ctx is %NULL, qio_channel_yield()
|
|
* uses QEMU's main thread event loop.
|
|
*
|
|
* You can move a #QIOChannel from one #AioContext to another even if
|
|
* I/O handlers are set for a coroutine. However, #QIOChannel provides
|
|
* no synchronization between the calls to qio_channel_yield() and
|
|
* qio_channel_attach_aio_context().
|
|
*
|
|
* Therefore you should first call qio_channel_detach_aio_context()
|
|
* to ensure that the coroutine is not entered concurrently. Then,
|
|
* while the coroutine has yielded, call qio_channel_attach_aio_context(),
|
|
* and then aio_co_schedule() to place the coroutine on the new
|
|
* #AioContext. The calls to qio_channel_detach_aio_context()
|
|
* and qio_channel_attach_aio_context() should be protected with
|
|
* aio_context_acquire() and aio_context_release().
|
|
*/
|
|
void qio_channel_attach_aio_context(QIOChannel *ioc,
|
|
AioContext *ctx);
|
|
|
|
/**
|
|
* qio_channel_detach_aio_context:
|
|
* @ioc: the channel object
|
|
*
|
|
* Disable any I/O handlers set by qio_channel_yield(). With the
|
|
* help of aio_co_schedule(), this allows moving a coroutine that was
|
|
* paused by qio_channel_yield() to another context.
|
|
*/
|
|
void qio_channel_detach_aio_context(QIOChannel *ioc);
|
|
|
|
/**
|
|
* qio_channel_yield:
|
|
* @ioc: the channel object
|
|
* @condition: the I/O condition to wait for
|
|
*
|
|
* Yields execution from the current coroutine until the condition
|
|
* indicated by @condition becomes available. @condition must
|
|
* be either %G_IO_IN or %G_IO_OUT; it cannot contain both. In
|
|
* addition, no two coroutine can be waiting on the same condition
|
|
* and channel at the same time.
|
|
*
|
|
* This must only be called from coroutine context. It is safe to
|
|
* reenter the coroutine externally while it is waiting; in this
|
|
* case the function will return even if @condition is not yet
|
|
* available.
|
|
*/
|
|
void coroutine_fn qio_channel_yield(QIOChannel *ioc,
|
|
GIOCondition condition);
|
|
|
|
/**
|
|
* qio_channel_wait:
|
|
* @ioc: the channel object
|
|
* @condition: the I/O condition to wait for
|
|
*
|
|
* Block execution from the current thread until
|
|
* the condition indicated by @condition becomes
|
|
* available.
|
|
*
|
|
* This will enter a nested event loop to perform
|
|
* the wait.
|
|
*/
|
|
void qio_channel_wait(QIOChannel *ioc,
|
|
GIOCondition condition);
|
|
|
|
/**
|
|
* qio_channel_set_aio_fd_handler:
|
|
* @ioc: the channel object
|
|
* @ctx: the AioContext to set the handlers on
|
|
* @io_read: the read handler
|
|
* @io_write: the write handler
|
|
* @opaque: the opaque value passed to the handler
|
|
*
|
|
* This is used internally by qio_channel_yield(). It can
|
|
* be used by channel implementations to forward the handlers
|
|
* to another channel (e.g. from #QIOChannelTLS to the
|
|
* underlying socket).
|
|
*/
|
|
void qio_channel_set_aio_fd_handler(QIOChannel *ioc,
|
|
AioContext *ctx,
|
|
IOHandler *io_read,
|
|
IOHandler *io_write,
|
|
void *opaque);
|
|
|
|
#endif /* QIO_CHANNEL_H */
|