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 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 typedef struct QIOChannelCommand QIOChannelCommand;
  29 DECLARE_INSTANCE_CHECKER(QIOChannelCommand, QIO_CHANNEL_COMMAND,
  30                          TYPE_QIO_CHANNEL_COMMAND)
  31
  32
  33
  34 /**
  35  * QIOChannelCommand:
  36  *
  37  * The QIOChannelCommand class provides a channel implementation
  38  * that can transport data with an externally running command
  39  * via its stdio streams.
  40  */
  41
  42 struct QIOChannelCommand {
  43     QIOChannel parent;
  44     int writefd;
  45     int readfd;
  46     pid_t pid;
  47 };
  48
  49
  50 /**
  51  * qio_channel_command_new_pid:
  52  * @writefd: the FD connected to the command's stdin
  53  * @readfd: the FD connected to the command's stdout
  54  * @pid: the PID of the running child command
  55  * @errp: pointer to a NULL-initialized error object
  56  *
  57  * Create a channel for performing I/O with the
  58  * previously spawned command identified by @pid.
  59  * The two file descriptors provide the connection
  60  * to command's stdio streams, either one or which
  61  * may be -1 to indicate that stream is not open.
  62  *
  63  * The channel will take ownership of the process
  64  * @pid and will kill it when closing the channel.
  65  * Similarly it will take responsibility for
  66  * closing the file descriptors @writefd and @readfd.
  67  *
  68  * Returns: the command channel object, or NULL on error
  69  */
  70 QIOChannelCommand *
  71 qio_channel_command_new_pid(int writefd,
  72                             int readfd,
  73                             pid_t pid);
  74
  75 /**
  76  * qio_channel_command_new_spawn:
  77  * @argv: the NULL terminated list of command arguments
  78  * @flags: the I/O mode, one of O_RDONLY, O_WRONLY, O_RDWR
  79  * @errp: pointer to a NULL-initialized error object
  80  *
  81  * Create a channel for performing I/O with the
  82  * command to be spawned with arguments @argv.
  83  *
  84  * Returns: the command channel object, or NULL on error
  85  */
  86 QIOChannelCommand *
  87 qio_channel_command_new_spawn(const char *const argv[],
  88                               int flags,
  89                               Error **errp);
  90
  91
  92 #endif /* QIO_CHANNEL_COMMAND_H */