1867bc2210
Fixes the -Wunused-parameter warning in: * group/group_signal.c: group_signal() * irq/irq_unexpectedisr.c: irq_unexpected_isr() * task/task_spawn.c: nxtask_spawn_proxy() * timer/timer_getoverrun.c: timer_getoverrun() * misc/dev_null.c: devnull_read(), devnull_write(), devnull_poll() * misc/dev_zero.c: devzero_read(), devzero_write(), devzero_poll() * syslog/syslog_channel.c: syslog_default_write() * syslog/syslog_device.c: syslog_dev_flush() * grp/lib_initgroups.c: initgroups() * misc/lib_mknod.c: mknod() * misc/lib_glob.c: ignore_err() * pthread/pthread_barrierinit.c: pthread_barrier_init() * pthread/pthread_atfork.c: pthread_atfork() * semaphore/sem_init.c: nxsem_init() * stream/lib_nullinstream.c: nullinstream_getc() * stream/lib_nulloutstream.c: nulloutstream_putc() * stream/lib_libnoflush.c: lib_noflush() * stream/lib_libsnoflush.c: lib_snoflush() * string/lib_strerror.c: strerror() * time/lib_gettimeofday.c: gettimeofday() * time/lib_settimeofday.c: settimeofday() * unistd/lib_pathconf.c: fpathconf(), pathconf() * unistd/lib_getrusage.c: getrusage() * unistd/lib_setrlimit.c: setrlimit() * unistd/lib_getrlimit.c: getrlimit() * unistd/lib_setpriority.c: setpriority()
133 lines
4.2 KiB
C
133 lines
4.2 KiB
C
/****************************************************************************
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* drivers/misc/dev_zero.c
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*
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* Licensed to the Apache Software Foundation (ASF) under one or more
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* contributor license agreements. See the NOTICE file distributed with
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* this work for additional information regarding copyright ownership. The
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* ASF licenses this file to you under the Apache License, Version 2.0 (the
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* "License"); you may not use this file except in compliance with the
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* License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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* License for the specific language governing permissions and limitations
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* under the License.
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*
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****************************************************************************/
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/****************************************************************************
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* Included Files
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****************************************************************************/
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#include <nuttx/config.h>
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#include <sys/types.h>
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#include <stdbool.h>
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#include <string.h>
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#include <poll.h>
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#include <errno.h>
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#include <nuttx/semaphore.h>
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#include <nuttx/fs/fs.h>
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#include <nuttx/drivers/drivers.h>
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/****************************************************************************
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* Private Function Prototypes
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****************************************************************************/
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static ssize_t devzero_read(FAR struct file *filep, FAR char *buffer,
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size_t buflen);
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static ssize_t devzero_write(FAR struct file *filep, FAR const char *buffer,
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size_t buflen);
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static int devzero_poll(FAR struct file *filep, FAR struct pollfd *fds,
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bool setup);
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/****************************************************************************
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* Private Data
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****************************************************************************/
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static const struct file_operations devzero_fops =
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{
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NULL, /* open */
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NULL, /* close */
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devzero_read, /* read */
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devzero_write, /* write */
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NULL, /* seek */
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NULL, /* ioctl */
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devzero_poll /* poll */
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#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
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, NULL /* unlink */
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#endif
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};
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/****************************************************************************
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* Private Functions
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****************************************************************************/
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/****************************************************************************
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* Name: devzero_read
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****************************************************************************/
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static ssize_t devzero_read(FAR struct file *filep, FAR char *buffer,
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size_t len)
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{
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UNUSED(filep);
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memset(buffer, 0, len);
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return len;
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}
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/****************************************************************************
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* Name: devzero_write
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****************************************************************************/
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static ssize_t devzero_write(FAR struct file *filep, FAR const char *buffer,
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size_t len)
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{
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UNUSED(filep);
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UNUSED(buffer);
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return len;
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}
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/****************************************************************************
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* Name: devzero_poll
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****************************************************************************/
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static int devzero_poll(FAR struct file *filep, FAR struct pollfd *fds,
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bool setup)
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{
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UNUSED(filep);
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if (setup)
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{
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fds->revents |= (fds->events & (POLLIN | POLLOUT));
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if (fds->revents != 0)
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{
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nxsem_post(fds->sem);
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}
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}
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return OK;
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}
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/****************************************************************************
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* Public Functions
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****************************************************************************/
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/****************************************************************************
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* Name: devzero_register
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*
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* Description:
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* Register /dev/zero
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*
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****************************************************************************/
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void devzero_register(void)
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{
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register_driver("/dev/zero", &devzero_fops, 0666, NULL);
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}
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