include/io/channel-file.h

   1 /*
   2  * QEMU I/O channels files 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_FILE_H
  22 #define QIO_CHANNEL_FILE_H
  23
  24 #include "io/channel.h"
  25 #include "qom/object.h"
  26
  27 #define TYPE_QIO_CHANNEL_FILE "qio-channel-file"
  28 typedef struct QIOChannelFile QIOChannelFile;
  29 DECLARE_INSTANCE_CHECKER(QIOChannelFile, QIO_CHANNEL_FILE,
  30                          TYPE_QIO_CHANNEL_FILE)
  31
  32
  33 /**
  34  * QIOChannelFile:
  35  *
  36  * The QIOChannelFile object provides a channel implementation
  37  * that is able to perform I/O on block devices, character
  38  * devices, FIFOs, pipes and plain files. While it is technically
  39  * able to work on sockets too on the UNIX platform, this is not
  40  * portable to Windows and lacks some extra sockets specific
  41  * functionality. So the QIOChannelSocket object is recommended
  42  * for that use case.
  43  *
  44  */
  45
  46 struct QIOChannelFile {
  47     QIOChannel parent;
  48     int fd;
  49 };
  50
  51
  52 /**
  53  * qio_channel_file_new_fd:
  54  * @fd: the file descriptor
  55  *
  56  * Create a new IO channel object for a file represented
  57  * by the @fd parameter. @fd can be associated with a
  58  * block device, character device, fifo, pipe, or a
  59  * regular file. For sockets, the QIOChannelSocket class
  60  * should be used instead, as this provides greater
  61  * functionality and cross platform portability.
  62  *
  63  * The channel will own the passed in file descriptor
  64  * and will take responsibility for closing it, so the
  65  * caller must not close it. If appropriate the caller
  66  * should dup() its FD before opening the channel.
  67  *
  68  * Returns: the new channel object
  69  */
  70 QIOChannelFile *
  71 qio_channel_file_new_fd(int fd);
  72
  73 /**
  74  * qio_channel_file_new_path:
  75  * @path: the file path
  76  * @flags: the open flags (O_RDONLY|O_WRONLY|O_RDWR, etc)
  77  * @mode: the file creation mode if O_CREAT is set in @flags
  78  * @errp: pointer to initialized error object
  79  *
  80  * Create a new IO channel object for a file represented
  81  * by the @path parameter. @path can point to any
  82  * type of file on which sequential I/O can be
  83  * performed, whether it be a plain file, character
  84  * device or block device.
  85  *
  86  * Returns: the new channel object
  87  */
  88 QIOChannelFile *
  89 qio_channel_file_new_path(const char *path,
  90                           int flags,
  91                           mode_t mode,
  92                           Error **errp);
  93
  94 #endif /* QIO_CHANNEL_FILE_H */