802 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			C
		
	
	
		
			Executable File
		
	
	
	
	
			
		
		
	
	
			802 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			C
		
	
	
		
			Executable File
		
	
	
	
	
| /*
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|  * Copyright (c) 2006-2023, RT-Thread Development Team
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|  *
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|  * SPDX-License-Identifier: Apache-2.0
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|  *
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|  * Change Logs:
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|  * Date           Author       Notes
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|  * 2012-09-30     Bernard      first version.
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|  * 2017-11-08     JasonJiaJie  fix memory leak issue when close a pipe.
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|  * 2023-06-28     shell        return POLLHUP when writer closed its channel on poll()
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|  *                             fix flag test on pipe_fops_open()
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|  * 2023-12-02     shell        Make read pipe operation interruptable.
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|  */
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| #include <rthw.h>
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| #include <rtdevice.h>
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| #include <stdint.h>
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| #include <sys/errno.h>
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| #include <ipc/condvar.h>
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| 
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| #if defined(RT_USING_POSIX_DEVIO) && defined(RT_USING_POSIX_PIPE)
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| #include <unistd.h>
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| #include <fcntl.h>
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| #include <poll.h>
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| #include <sys/ioctl.h>
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| #include <dfs_file.h>
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| #include <resource_id.h>
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| 
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| /* check RT_UNAMED_PIPE_NUMBER */
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| 
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| #ifndef RT_UNAMED_PIPE_NUMBER
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| #define RT_UNAMED_PIPE_NUMBER 64
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| #endif
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| 
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| #define BITS(x) _BITS(x)
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| #define _BITS(x) (sizeof(#x) - 1)
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| 
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| struct check_rt_unamed_pipe_number
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| {
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|     /* -4 for "pipe" prefix */
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|     /* -1 for '\0' postfix */
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|     char _check[RT_NAME_MAX - 4 - 1 - BITS(RT_UNAMED_PIPE_NUMBER)];
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| };
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| 
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| /* check end */
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| 
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| static void *resoure_id[RT_UNAMED_PIPE_NUMBER];
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| static resource_id_t id_mgr = RESOURCE_ID_INIT(RT_UNAMED_PIPE_NUMBER, resoure_id);
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| 
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| /**
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|  * @brief    This function will open a pipe.
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|  *
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|  * @param    fd is the file descriptor.
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|  *
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|  * @return   Return the operation status.
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|  *           When the return value is 0, it means the operation is successful.
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|  *           When the return value is -1, it means the file descriptor is invalid.
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|  *           When the return value is -RT_ENOMEM, it means insufficient memory allocation failed.
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|  */
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| static int pipe_fops_open(struct dfs_file *fd)
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| {
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|     int rc = 0;
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|     rt_pipe_t *pipe;
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| 
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|     pipe = (rt_pipe_t *)fd->vnode->data;
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|     if (!pipe)
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|     {
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|         return -1;
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|     }
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| 
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|     rt_mutex_take(&pipe->lock, RT_WAITING_FOREVER);
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| 
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|     if ((fd->flags & O_ACCMODE) == O_RDONLY)
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|     {
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|         pipe->reader += 1;
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|     }
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| 
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|     if ((fd->flags & O_ACCMODE) == O_WRONLY)
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|     {
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|         pipe->writer += 1;
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|     }
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|     if (fd->vnode->ref_count == 1)
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|     {
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|         pipe->fifo = rt_ringbuffer_create(pipe->bufsz);
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|         if (pipe->fifo == RT_NULL)
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|         {
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|             rc = -RT_ENOMEM;
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|             goto __exit;
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|         }
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|     }
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| 
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|     if ((fd->flags & O_ACCMODE) == O_RDONLY && !pipe->writer)
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|     {
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|         /* wait for partner */
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|         rc = rt_condvar_timedwait(&pipe->waitfor_parter, &pipe->lock,
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|                                   RT_INTERRUPTIBLE, RT_WAITING_FOREVER);
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|         if (rc != 0)
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|         {
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|             pipe->reader--;
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|         }
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|     }
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|     else if ((fd->flags & O_ACCMODE) == O_WRONLY)
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|     {
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|         rt_condvar_broadcast(&pipe->waitfor_parter);
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|     }
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| 
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| __exit:
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|     rt_mutex_release(&pipe->lock);
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| 
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|     return rc;
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| }
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| 
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| /**
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|  * @brief    This function will close a pipe.
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|  *
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|  * @param    fd is the file descriptor.
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|  *
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|  * @return   Return the operation status.
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|  *           When the return value is 0, it means the operation is successful.
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|  *           When the return value is -1, it means the file descriptor is invalid.
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|  */
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| static int pipe_fops_close(struct dfs_file *fd)
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| {
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|     rt_device_t device;
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|     rt_pipe_t *pipe;
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| 
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|     pipe = (rt_pipe_t *)fd->vnode->data;
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|     if (!pipe)
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|     {
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|         return -1;
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|     }
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| 
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|     device = &pipe->parent;
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|     rt_mutex_take(&pipe->lock, RT_WAITING_FOREVER);
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| 
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|     if ((fd->flags & O_RDONLY) == O_RDONLY)
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|     {
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|         pipe->reader -= 1;
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|     }
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| 
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|     if ((fd->flags & O_WRONLY) == O_WRONLY)
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|     {
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|         pipe->writer -= 1;
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|         while (!rt_list_isempty(&pipe->reader_queue.waiting_list))
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|         {
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|             rt_wqueue_wakeup(&pipe->reader_queue, (void*)POLLIN);
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|         }
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|     }
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| 
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|     if (fd->vnode->ref_count == 1)
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|     {
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|         if (pipe->fifo != RT_NULL)
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|         {
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|             rt_ringbuffer_destroy(pipe->fifo);
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|         }
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|         pipe->fifo = RT_NULL;
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|     }
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| 
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|     rt_mutex_release(&pipe->lock);
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| 
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|     if (fd->vnode->ref_count == 1 && pipe->is_named == RT_FALSE)
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|     {
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|         /* delete the unamed pipe */
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|         rt_pipe_delete(device->parent.name);
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|     }
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| 
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|     return 0;
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| }
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| 
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| /**
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|  * @brief    This function will get the pipe space size depends on the command.
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|  *
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|  * @param    fd is the file descriptor.
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|  *
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|  * @param    cmd is the command. It determines what data will get.
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|  *
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|  *               FIONREAD        The command to get the number of bytes in the pipe.
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|  *
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|  *               FIONWRITE       The command to get the number of bytes can be written to the pipe.
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|  *
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|  * @param    args is the pointer to the data to store the read data.
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|  *
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|  * @return   Return the operation status.
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|  *           When the return value is 0, it means the operation is successful.
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|  *           When the return value is -EINVAL, it means the command is invalid.
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|  */
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| static int pipe_fops_ioctl(struct dfs_file *fd, int cmd, void *args)
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| {
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|     rt_pipe_t *pipe;
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|     int ret = 0;
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| 
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|     pipe = (rt_pipe_t *)fd->vnode->data;
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| 
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|     switch (cmd)
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|     {
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|     case FIONREAD:
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|         *((int*)args) = rt_ringbuffer_data_len(pipe->fifo);
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|         break;
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|     case FIONWRITE:
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|         *((int*)args) = rt_ringbuffer_space_len(pipe->fifo);
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|         break;
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|     default:
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|         ret = -EINVAL;
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|         break;
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|     }
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| 
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|     return ret;
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| }
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| 
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| /**
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|  * @brief    This function will read data from pipe.
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|  *
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|  * @param    fd is the file descriptor.
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|  *
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|  * @param    buf is the buffer to store the read data.
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|  *
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|  * @param    count is the length of data to be read.
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|  *
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|  * @return   Return the length of data read.
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|  *           When the return value is 0, it means O_NONBLOCK is enabled and there is no thread that has the pipe open for writing.
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|  *           When the return value is -EAGAIN, it means there are no data to be read.
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|  */
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| #ifdef RT_USING_DFS_V2
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| static ssize_t pipe_fops_read(struct dfs_file *fd, void *buf, size_t count, off_t *pos)
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| #else
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| static ssize_t pipe_fops_read(struct dfs_file *fd, void *buf, size_t count)
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| #endif
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| {
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|     int len = 0;
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|     rt_pipe_t *pipe;
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| 
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|     pipe = (rt_pipe_t *)fd->vnode->data;
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| 
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|     /* no process has the pipe open for writing, return end-of-file */
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|     rt_mutex_take(&pipe->lock, RT_WAITING_FOREVER);
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| 
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|     while (1)
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|     {
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|         len = rt_ringbuffer_get(pipe->fifo, buf, count);
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| 
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|         if (len > 0 || pipe->writer == 0)
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|         {
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|             break;
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|         }
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|         else
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|         {
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|             if (fd->flags & O_NONBLOCK)
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|             {
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|                 len = -EAGAIN;
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|                 goto out;
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|             }
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| 
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|             rt_mutex_release(&pipe->lock);
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|             rt_wqueue_wakeup(&pipe->writer_queue, (void*)POLLOUT);
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|             if (rt_wqueue_wait_interruptible(&pipe->reader_queue, 0, -1) == -RT_EINTR)
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|                 return -EINTR;
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|             rt_mutex_take(&pipe->lock, RT_WAITING_FOREVER);
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|         }
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|     }
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| 
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|     /* wakeup writer */
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|     rt_wqueue_wakeup(&pipe->writer_queue, (void*)POLLOUT);
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| 
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| out:
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|     rt_mutex_release(&pipe->lock);
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|     return len;
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| }
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| 
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| /**
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|  * @brief    This function will write data to pipe.
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|  *
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|  * @param    fd is the file descriptor.
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|  *
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|  * @param    buf is a pointer to the data buffer to be written.
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|  *
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|  * @param    count is the length of data to be write.
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|  *
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|  * @return   Return the length of data written.
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|  *           When the return value is -EAGAIN, it means O_NONBLOCK is enabled and there are no space to be written.
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|  *           When the return value is -EPIPE, it means there is no thread that has the pipe open for reading.
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|  */
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| #ifdef RT_USING_DFS_V2
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| static ssize_t pipe_fops_write(struct dfs_file *fd, const void *buf, size_t count, off_t *pos)
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| #else
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| static ssize_t pipe_fops_write(struct dfs_file *fd, const void *buf, size_t count)
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| #endif
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| {
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|     int len;
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|     rt_pipe_t *pipe;
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|     int wakeup = 0;
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|     int ret = 0;
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|     uint8_t *pbuf;
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| 
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|     pipe = (rt_pipe_t *)fd->vnode->data;
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| 
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|     if (count == 0)
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|     {
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|         return 0;
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|     }
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| 
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|     pbuf = (uint8_t*)buf;
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|     rt_mutex_take(&pipe->lock, -1);
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| 
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|     while (1)
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|     {
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|         len = rt_ringbuffer_put(pipe->fifo, pbuf, count - ret);
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|         ret +=  len;
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|         pbuf += len;
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|         wakeup = 1;
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| 
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|         if (ret == count)
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|         {
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|             break;
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|         }
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|         else
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|         {
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|             if (fd->flags & O_NONBLOCK)
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|             {
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|                 if (ret == 0)
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|                 {
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|                     ret = -EAGAIN;
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|                 }
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| 
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|                 break;
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|             }
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|         }
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| 
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|         rt_mutex_release(&pipe->lock);
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|         rt_wqueue_wakeup(&pipe->reader_queue, (void*)POLLIN);
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|         /* pipe full, waiting on suspended write list */
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|         if (rt_wqueue_wait_interruptible(&pipe->writer_queue, 0, -1) == -RT_EINTR)
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|             return -EINTR;
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|         rt_mutex_take(&pipe->lock, -1);
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|     }
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|     rt_mutex_release(&pipe->lock);
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| 
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|     if (wakeup)
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|     {
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|         rt_wqueue_wakeup(&pipe->reader_queue, (void*)POLLIN);
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|     }
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| 
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|     return ret;
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| }
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| 
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| /**
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|  * @brief    This function will get the pipe status.
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|  *
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|  * @param    fd is the file descriptor.
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|  *
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|  * @param    req is the request type.
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|  *
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|  * @return   mask of the pipe status.
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|  *           POLLIN means there is data to be read.
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|  *           POLLHUP means there is no thread that occupied the pipe to open for writing.
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|  *           POLLOUT means there is space to be written.
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|  *           POLLERR means there is no thread that occupied the pipe to open for reading.
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|  */
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| static int pipe_fops_poll(struct dfs_file *fd, rt_pollreq_t *req)
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| {
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|     int mask = 0;
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|     rt_pipe_t *pipe;
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|     int mode = 0;
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|     pipe = (rt_pipe_t *)fd->vnode->data;
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| 
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|     rt_poll_add(&pipe->reader_queue, req);
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|     rt_poll_add(&pipe->writer_queue, req);
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| 
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|     switch (fd->flags & O_ACCMODE)
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|     {
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|     case O_RDONLY:
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|         mode = 1;
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|         break;
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|     case O_WRONLY:
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|         mode = 2;
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|         break;
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|     case O_RDWR:
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|         mode = 3;
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|         break;
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|     }
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| 
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|     if (mode & 1)
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|     {
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|         if (rt_ringbuffer_data_len(pipe->fifo) != 0)
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|         {
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|             mask |= POLLIN;
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|         }
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|         else if (pipe->writer == 0)
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|         {
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|             mask = POLLHUP;
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|         }
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|     }
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| 
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|     if (mode & 2)
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|     {
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|         if (rt_ringbuffer_space_len(pipe->fifo) != 0)
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|         {
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|             mask |= POLLOUT;
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|         }
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|     }
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| 
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|     return mask;
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| }
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| 
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| static const struct dfs_file_ops pipe_fops =
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| {
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|     .open  = pipe_fops_open,
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|     .close = pipe_fops_close,
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|     .ioctl = pipe_fops_ioctl,
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|     .read  = pipe_fops_read,
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|     .write = pipe_fops_write,
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|     .poll  = pipe_fops_poll,
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| };
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| #endif /* defined(RT_USING_POSIX_DEVIO) && defined(RT_USING_POSIX_PIPE) */
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| 
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| /**
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|  * @brief    This function will open the pipe and actually creates the pipe buffer.
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|  *
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|  * @param    device is a pointer to the pipe device descriptor.
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|  *
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|  * @param    oflag is the open method, but it is not used yet.
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|  *
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|  * @return   Return the operation status.
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|  *           When the return value is RT_EOK, the operation is successful.
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|  *           When the return value is -RT_EINVAL, it means the device handle is empty.
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|  *           When the return value is -RT_ENOMEM, it means insufficient memory allocation failed.
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|  */
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| rt_err_t rt_pipe_open(rt_device_t device, rt_uint16_t oflag)
 | |
| {
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|     rt_pipe_t *pipe = (rt_pipe_t *)device;
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|     rt_err_t ret = RT_EOK;
 | |
| 
 | |
|     if (device == RT_NULL)
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|     {
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|         ret = -RT_EINVAL;
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|         goto __exit;
 | |
|     }
 | |
| 
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|     rt_mutex_take(&pipe->lock, RT_WAITING_FOREVER);
 | |
| 
 | |
|     if (pipe->fifo == RT_NULL)
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|     {
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|         pipe->fifo = rt_ringbuffer_create(pipe->bufsz);
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|         if (pipe->fifo == RT_NULL)
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|         {
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|             ret = -RT_ENOMEM;
 | |
|         }
 | |
|     }
 | |
| 
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|     rt_mutex_release(&pipe->lock);
 | |
| 
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| __exit:
 | |
|     return ret;
 | |
| }
 | |
| 
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| /**
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|  * @brief    This function will close the pipe and release the pipe buffer.
 | |
|  *
 | |
|  * @param    device is a pointer to the pipe device descriptor.
 | |
|  *
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|  * @return   Return the operation status.
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|  *           When the return value is RT_EOK, the operation is successful.
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|  *           When the return value is -RT_EINVAL, it means the device handle is empty.
 | |
|  */
 | |
| rt_err_t rt_pipe_close(rt_device_t device)
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| {
 | |
|     rt_pipe_t *pipe = (rt_pipe_t *)device;
 | |
| 
 | |
|     if (device == RT_NULL)
 | |
|     {
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|         return -RT_EINVAL;
 | |
|     }
 | |
|     rt_mutex_take(&pipe->lock, RT_WAITING_FOREVER);
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| 
 | |
|     rt_ringbuffer_destroy(pipe->fifo);
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|     pipe->fifo = RT_NULL;
 | |
| 
 | |
|     rt_mutex_release(&pipe->lock);
 | |
| 
 | |
|     return RT_EOK;
 | |
| }
 | |
| 
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| /**
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|  * @brief    This function will read the specified length of data from the pipe.
 | |
|  *
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|  * @param    device is a pointer to the pipe device descriptor.
 | |
|  *
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|  * @param    pos is a parameter compatible with POSIX standard interface (currently meaningless, just pass in 0).
 | |
|  *
 | |
|  * @param    buffer is a pointer to the buffer to store the read data.
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|  *
 | |
|  * @param    count is the length of data to be read.
 | |
|  *
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|  * @return   Return the length of data read.
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|  *           When the return value is 0, it means the pipe device handle is empty or the count is 0.
 | |
|  */
 | |
| rt_ssize_t rt_pipe_read(rt_device_t device, rt_off_t pos, void *buffer, rt_size_t count)
 | |
| {
 | |
|     uint8_t *pbuf;
 | |
|     rt_size_t read_bytes = 0;
 | |
|     rt_pipe_t *pipe = (rt_pipe_t *)device;
 | |
| 
 | |
|     if (device == RT_NULL)
 | |
|     {
 | |
|         rt_set_errno(-EINVAL);
 | |
|         return 0;
 | |
|     }
 | |
|     if (count == 0)
 | |
|     {
 | |
|         return 0;
 | |
|     }
 | |
| 
 | |
|     pbuf = (uint8_t*)buffer;
 | |
|     rt_mutex_take(&pipe->lock, RT_WAITING_FOREVER);
 | |
| 
 | |
|     while (read_bytes < count)
 | |
|     {
 | |
|         int len = rt_ringbuffer_get(pipe->fifo, &pbuf[read_bytes], count - read_bytes);
 | |
|         if (len <= 0)
 | |
|         {
 | |
|             break;
 | |
|         }
 | |
| 
 | |
|         read_bytes += len;
 | |
|     }
 | |
|     rt_mutex_release(&pipe->lock);
 | |
| 
 | |
|     return read_bytes;
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * @brief    This function will write the specified length of data to the pipe.
 | |
|  *
 | |
|  * @param    device is a pointer to the pipe device descriptor.
 | |
|  *
 | |
|  * @param    pos is a parameter compatible with POSIX standard interface (currently meaningless, just pass in 0).
 | |
|  *
 | |
|  * @param    buffer is a pointer to the data buffer to be written.
 | |
|  *
 | |
|  * @param    count is the length of data to be written.
 | |
|  *
 | |
|  * @return   Return the length of data written.
 | |
|  *           When the return value is 0, it means the pipe device handle is empty or the count is 0.
 | |
|  */
 | |
| rt_ssize_t rt_pipe_write(rt_device_t device, rt_off_t pos, const void *buffer, rt_size_t count)
 | |
| {
 | |
|     uint8_t *pbuf;
 | |
|     rt_size_t write_bytes = 0;
 | |
|     rt_pipe_t *pipe = (rt_pipe_t *)device;
 | |
| 
 | |
|     if (device == RT_NULL)
 | |
|     {
 | |
|         rt_set_errno(-EINVAL);
 | |
|         return 0;
 | |
|     }
 | |
|     if (count == 0)
 | |
|     {
 | |
|         return 0;
 | |
|     }
 | |
| 
 | |
|     pbuf = (uint8_t*)buffer;
 | |
|     rt_mutex_take(&pipe->lock, -1);
 | |
| 
 | |
|     while (write_bytes < count)
 | |
|     {
 | |
|         int len = rt_ringbuffer_put(pipe->fifo, &pbuf[write_bytes], count - write_bytes);
 | |
|         if (len <= 0)
 | |
|         {
 | |
|             break;
 | |
|         }
 | |
| 
 | |
|         write_bytes += len;
 | |
|     }
 | |
|     rt_mutex_release(&pipe->lock);
 | |
| 
 | |
|     return write_bytes;
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * @brief    This function is not used yet.
 | |
|  *
 | |
|  * @param    dev is not used yet.
 | |
|  *
 | |
|  * @param    cmd is not used yet.
 | |
|  *
 | |
|  * @param    args is not used yet.
 | |
|  *
 | |
|  * @return   Always return RT_EOK.
 | |
|  */
 | |
| rt_err_t rt_pipe_control(rt_device_t dev, int cmd, void *args)
 | |
| {
 | |
|     return RT_EOK;
 | |
| }
 | |
| 
 | |
| #ifdef RT_USING_DEVICE_OPS
 | |
| const static struct rt_device_ops pipe_ops =
 | |
| {
 | |
|     RT_NULL,
 | |
|     rt_pipe_open,
 | |
|     rt_pipe_close,
 | |
|     rt_pipe_read,
 | |
|     rt_pipe_write,
 | |
|     rt_pipe_control,
 | |
| };
 | |
| #endif /* RT_USING_DEVICE_OPS */
 | |
| 
 | |
| /**
 | |
|  * @brief    This function will initialize a pipe device.
 | |
|  *           The system allocates a pipe handle from dynamic heap memory, initializes the pipe handle
 | |
|  *           with the specified value, and registers the pipe device with the system.
 | |
|  *
 | |
|  * @param    name is the name of pipe device.
 | |
|  *
 | |
|  * @param    bufsz is the size of pipe buffer.
 | |
|  *
 | |
|  * @return   Return the pointer to the pipe device.
 | |
|  *           When the return value is RT_NULL, it means the initialization failed.
 | |
|  */
 | |
| rt_pipe_t *rt_pipe_create(const char *name, int bufsz)
 | |
| {
 | |
|     rt_pipe_t *pipe;
 | |
|     rt_device_t dev;
 | |
| 
 | |
|     pipe = (rt_pipe_t *)rt_malloc(sizeof(rt_pipe_t));
 | |
|     if (pipe == RT_NULL) return RT_NULL;
 | |
| 
 | |
|     rt_memset(pipe, 0, sizeof(rt_pipe_t));
 | |
|     pipe->is_named = RT_TRUE; /* initialize as a named pipe */
 | |
| #if defined(RT_USING_POSIX_DEVIO) && defined(RT_USING_POSIX_PIPE)
 | |
|     pipe->pipeno = -1;
 | |
| #endif
 | |
|     rt_mutex_init(&pipe->lock, name, RT_IPC_FLAG_FIFO);
 | |
|     rt_wqueue_init(&pipe->reader_queue);
 | |
|     rt_wqueue_init(&pipe->writer_queue);
 | |
|     rt_condvar_init(&pipe->waitfor_parter, "piwfp");
 | |
| 
 | |
|     pipe->writer = 0;
 | |
|     pipe->reader = 0;
 | |
| 
 | |
|     RT_ASSERT(bufsz < 0xFFFF);
 | |
|     pipe->bufsz = bufsz;
 | |
| 
 | |
|     dev = &pipe->parent;
 | |
|     dev->type = RT_Device_Class_Pipe;
 | |
| #ifdef RT_USING_DEVICE_OPS
 | |
|     dev->ops         = &pipe_ops;
 | |
| #else
 | |
|     dev->init        = RT_NULL;
 | |
|     dev->open        = rt_pipe_open;
 | |
|     dev->read        = rt_pipe_read;
 | |
|     dev->write       = rt_pipe_write;
 | |
|     dev->close       = rt_pipe_close;
 | |
|     dev->control     = rt_pipe_control;
 | |
| #endif
 | |
| 
 | |
|     dev->rx_indicate = RT_NULL;
 | |
|     dev->tx_complete = RT_NULL;
 | |
| 
 | |
|     if (rt_device_register(&pipe->parent, name, RT_DEVICE_FLAG_RDWR | RT_DEVICE_FLAG_REMOVABLE) != 0)
 | |
|     {
 | |
|         rt_mutex_detach(&pipe->lock);
 | |
| #if defined(RT_USING_POSIX_DEVIO) && defined(RT_USING_POSIX_PIPE)
 | |
|         resource_id_put(&id_mgr, pipe->pipeno);
 | |
| #endif
 | |
|         rt_free(pipe);
 | |
|         return RT_NULL;
 | |
|     }
 | |
| #if defined(RT_USING_POSIX_DEVIO) && defined(RT_USING_POSIX_PIPE)
 | |
|     dev->fops = (void *)&pipe_fops;
 | |
| #endif
 | |
| 
 | |
|     return pipe;
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * @brief    This function will delete a pipe device.
 | |
|  *           The system will release the pipe handle and unregister the pipe device from the system.
 | |
|  *
 | |
|  * @param    pipe is the pointer to the pipe device.
 | |
|  *
 | |
|  * @return   Return the operation status.
 | |
|  *           When the return value is 0, it means the operation is successful.
 | |
|  *           When the return value is -RT_EINVAL, it means the pipe device is not found or the device isn't a pipe.
 | |
|  *           When the return value is -RT_EBUSY, it means the pipe device is busy.
 | |
|  */
 | |
| int rt_pipe_delete(const char *name)
 | |
| {
 | |
|     int result = 0;
 | |
|     rt_device_t device;
 | |
| 
 | |
|     device = rt_device_find(name);
 | |
|     if (device)
 | |
|     {
 | |
|         if (device->type == RT_Device_Class_Pipe)
 | |
|         {
 | |
|             rt_pipe_t *pipe;
 | |
| 
 | |
|             pipe = (rt_pipe_t *)device;
 | |
| 
 | |
|             rt_condvar_detach(&pipe->waitfor_parter);
 | |
|             rt_mutex_detach(&pipe->lock);
 | |
| #if defined(RT_USING_POSIX_DEVIO) && defined(RT_USING_POSIX_PIPE)
 | |
|             resource_id_put(&id_mgr, pipe->pipeno);
 | |
| #endif
 | |
|             rt_device_unregister(device);
 | |
| 
 | |
|             /* close fifo ringbuffer */
 | |
|             if (pipe->fifo)
 | |
|             {
 | |
|                 rt_ringbuffer_destroy(pipe->fifo);
 | |
|                 pipe->fifo = RT_NULL;
 | |
|             }
 | |
|             rt_free(pipe);
 | |
|         }
 | |
|         else
 | |
|         {
 | |
|             result = -ENODEV;
 | |
|         }
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|         result = -ENODEV;
 | |
|     }
 | |
| 
 | |
|     return result;
 | |
| }
 | |
| 
 | |
| #if defined(RT_USING_POSIX_DEVIO) && defined(RT_USING_POSIX_PIPE)
 | |
| /**
 | |
|  * @brief    This function will creat a anonymous pipe.
 | |
|  *
 | |
|  * @param    fildes[0] is the read handle.
 | |
|  *           fildes[1] is the write handle.
 | |
|  *
 | |
|  * @return   Return the operation status.
 | |
|  *           When the return value is 0, it means the operation is successful.
 | |
|  *           When the return value is -1, it means the operation is failed.
 | |
|  */
 | |
| int pipe(int fildes[2])
 | |
| {
 | |
|     rt_pipe_t *pipe;
 | |
|     char dname[8];
 | |
|     char dev_name[32];
 | |
|     int pipeno = 0;
 | |
| 
 | |
|     pipeno = resource_id_get(&id_mgr);
 | |
|     if (pipeno == -1)
 | |
|     {
 | |
|         return -1;
 | |
|     }
 | |
|     rt_snprintf(dname, sizeof(dname), "pipe%d", pipeno);
 | |
| 
 | |
|     pipe = rt_pipe_create(dname, RT_USING_POSIX_PIPE_SIZE);
 | |
|     if (pipe == RT_NULL)
 | |
|     {
 | |
|         resource_id_put(&id_mgr, pipeno);
 | |
|         return -1;
 | |
|     }
 | |
| 
 | |
|     pipe->is_named = RT_FALSE; /* unamed pipe */
 | |
|     pipe->pipeno = pipeno;
 | |
|     rt_snprintf(dev_name, sizeof(dev_name), "/dev/%s", dname);
 | |
| 
 | |
|     fildes[1] = open(dev_name, O_WRONLY, 0);
 | |
|     if (fildes[1] < 0)
 | |
|     {
 | |
|         close(fildes[0]);
 | |
|         return -1;
 | |
|     }
 | |
| 
 | |
|     fildes[0] = open(dev_name, O_RDONLY, 0);
 | |
|     if (fildes[0] < 0)
 | |
|     {
 | |
|         return -1;
 | |
|     }
 | |
| 
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * @brief    This function will create a named pipe.
 | |
|  *
 | |
|  * @param    path is the name of pipe device.
 | |
|  *
 | |
|  * @param    mode is not used yet.
 | |
|  *
 | |
|  * @return   Return the operation status.
 | |
|  *           When the return value is 0, it means the operation is successful.
 | |
|  *           When the return value is -1, it means the operation is failed.
 | |
|  */
 | |
| int mkfifo(const char *path, mode_t mode)
 | |
| {
 | |
|     rt_pipe_t *pipe;
 | |
| 
 | |
|     pipe = rt_pipe_create(path, RT_USING_POSIX_PIPE_SIZE);
 | |
|     if (pipe == RT_NULL)
 | |
|     {
 | |
|         return -1;
 | |
|     }
 | |
| 
 | |
|     return 0;
 | |
| }
 | |
| #endif /* defined(RT_USING_POSIX_DEVIO) && defined(RT_USING_POSIX_PIPE) */
 |