include/io/channel-command.h

   1 /*
   2  * QEMU I/O channels external command driver
   3  *
   4  * Copyright (c) 2015 Red Hat, Inc.
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  18  *
  19  */
  20
  21 #ifndef QIO_CHANNEL_COMMAND_H
  22 #define QIO_CHANNEL_COMMAND_H
  23
  24 #include "io/channel.h"
  25 #include "qom/object.h"
  26
  27 #define TYPE_QIO_CHANNEL_COMMAND "qio-channel-command"
  28 OBJECT_DECLARE_SIMPLE_TYPE(QIOChannelCommand, QIO_CHANNEL_COMMAND)
  29
  30
  31
  32 /**
  33  * QIOChannelCommand:
  34  *
  35  * The QIOChannelCommand class provides a channel implementation
  36  * that can transport data with an externally running command
  37  * via its stdio streams.
  38  */
  39
  40 struct QIOChannelCommand {
  41     QIOChannel parent;
  42     int writefd;
  43     int readfd;
  44     pid_t pid;
  45 };
  46
  47
  48 /**
  49  * qio_channel_command_new_pid:
  50  * @writefd: the FD connected to the command's stdin
  51  * @readfd: the FD connected to the command's stdout
  52  * @pid: the PID of the running child command
  53  * @errp: pointer to a NULL-initialized error object
  54  *
  55  * Create a channel for performing I/O with the
  56  * previously spawned command identified by @pid.
  57  * The two file descriptors provide the connection
  58  * to command's stdio streams, either one or which
  59  * may be -1 to indicate that stream is not open.
  60  *
  61  * The channel will take ownership of the process
  62  * @pid and will kill it when closing the channel.
  63  * Similarly it will take responsibility for
  64  * closing the file descriptors @writefd and @readfd.
  65  *
  66  * Returns: the command channel object, or NULL on error
  67  */
  68 QIOChannelCommand *
  69 qio_channel_command_new_pid(int writefd,
  70                             int readfd,
  71                             pid_t pid);
  72
  73 /**
  74  * qio_channel_command_new_spawn:
  75  * @argv: the NULL terminated list of command arguments
  76  * @flags: the I/O mode, one of O_RDONLY, O_WRONLY, O_RDWR
  77  * @errp: pointer to a NULL-initialized error object
  78  *
  79  * Create a channel for performing I/O with the
  80  * command to be spawned with arguments @argv.
  81  *
  82  * Returns: the command channel object, or NULL on error
  83  */
  84 QIOChannelCommand *
  85 qio_channel_command_new_spawn(const char *const argv[],
  86                               int flags,
  87                               Error **errp);
  88
  89
  90 #endif /* QIO_CHANNEL_COMMAND_H */