mirror of https://gitee.com/openkylin/linux.git
52 lines
980 B
C
52 lines
980 B
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Copyright (C) 2002 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com)
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*/
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#include <stddef.h>
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#include <errno.h>
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#include <fcntl.h>
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#include "chan_user.h"
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#include <os.h>
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/* This address is used only as a unique identifier */
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static int null_chan;
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static void *null_init(char *str, int device, const struct chan_opts *opts)
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{
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return &null_chan;
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}
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static int null_open(int input, int output, int primary, void *d,
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char **dev_out)
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{
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int fd;
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*dev_out = NULL;
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fd = open(DEV_NULL, O_RDWR);
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return (fd < 0) ? -errno : fd;
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}
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static int null_read(int fd, char *c_out, void *unused)
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{
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return -ENODEV;
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}
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static void null_free(void *data)
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{
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}
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const struct chan_ops null_ops = {
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.type = "null",
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.init = null_init,
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.open = null_open,
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.close = generic_close,
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.read = null_read,
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.write = generic_write,
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.console_write = generic_console_write,
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.window_size = generic_window_size,
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.free = null_free,
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.winch = 0,
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};
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