diff options
| author | [email protected] <[email protected]> | 2012-09-30 07:33:13 +0000 |
|---|---|---|
| committer | [email protected] <[email protected]> | 2012-09-30 07:33:13 +0000 |
| commit | 4f05dd5426c277cd1b14f7d20f678983f88b2c0a (patch) | |
| tree | 8056c39a8fda068c56375b7f3c4a7c647225726f /components/drivers/src/pipe.c | |
| parent | 5064df210f29ef0e8e83011a007bbb28983a42dd (diff) | |
Add pipe, data queue implementation; Fix the issue which leaks one item in the available data of ring buffer.
git-svn-id: https://rt-thread.googlecode.com/svn/trunk@2313 bbd45198-f89e-11dd-88c7-29a3b14d5316
Diffstat (limited to 'components/drivers/src/pipe.c')
| -rw-r--r-- | components/drivers/src/pipe.c | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/components/drivers/src/pipe.c b/components/drivers/src/pipe.c new file mode 100644 index 0000000000..142f1d9399 --- /dev/null +++ b/components/drivers/src/pipe.c @@ -0,0 +1,196 @@ +/*
+ * File : pipe.c
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2012, RT-Thread Development Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rt-thread.org/license/LICENSE
+ *
+ * Change Logs:
+ * Date Author Notes
+ * 2012-09-30 Bernard first version.
+ */
+#include <rthw.h>
+#include <rtthread.h>
+#include <rtdevice.h>
+
+static rt_size_t rt_pipe_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
+{
+ rt_uint32_t level;
+ rt_thread_t thread;
+ struct rt_pipe_device *pipe;
+ rt_size_t read_nbytes;
+
+ pipe = PIPE_DEVICE(dev);
+ RT_ASSERT(pipe != RT_NULL);
+
+ thread = rt_thread_self();
+
+ /* current context checking */
+ RT_DEBUG_NOT_IN_INTERRUPT;
+
+ do
+ {
+ level = rt_hw_interrupt_disable();
+ read_nbytes = rt_ringbuffer_get(&(pipe->ringbuffer), buffer, size);
+ if (read_nbytes == 0)
+ {
+ rt_thread_suspend(thread);
+ /* waiting on suspended read list */
+ rt_list_insert_before(&(pipe->suspended_read_list), &(thread->tlist));
+ rt_hw_interrupt_enable(level);
+
+ rt_schedule();
+ }
+ else
+ {
+ if (!rt_list_isempty(&pipe->suspended_write_list))
+ {
+ /* get suspended thread */
+ thread = rt_list_entry(pipe->suspended_write_list.next,
+ struct rt_thread, tlist);
+
+ /* resume the write thread */
+ rt_thread_resume(thread);
+ rt_hw_interrupt_enable(level);
+
+ rt_schedule();
+ }
+ else
+ {
+ rt_hw_interrupt_enable(level);
+ }
+ break;
+ }
+ } while (read_nbytes == 0);
+
+ return read_nbytes;
+}
+
+struct rt_pipe_device *_pipe = RT_NULL;
+static rt_size_t rt_pipe_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
+{
+ rt_uint32_t level;
+ rt_thread_t thread;
+ struct rt_pipe_device *pipe;
+ rt_size_t write_nbytes;
+
+ pipe = PIPE_DEVICE(dev);
+ RT_ASSERT(pipe != RT_NULL);
+ if (_pipe == RT_NULL)
+ _pipe = pipe;
+
+ thread = rt_thread_self();
+
+ /* current context checking */
+ RT_DEBUG_NOT_IN_INTERRUPT;
+
+ do
+ {
+ level = rt_hw_interrupt_disable();
+ write_nbytes = rt_ringbuffer_put(&(pipe->ringbuffer), buffer, size);
+ if (write_nbytes == 0)
+ {
+ /* pipe full, waiting on suspended write list */
+ rt_thread_suspend(thread);
+ /* waiting on suspended read list */
+ rt_list_insert_before(&(pipe->suspended_write_list), &(thread->tlist));
+ rt_hw_interrupt_enable(level);
+
+ rt_schedule();
+ }
+ else
+ {
+ if (!rt_list_isempty(&pipe->suspended_read_list))
+ {
+ /* get suspended thread */
+ thread = rt_list_entry(pipe->suspended_read_list.next,
+ struct rt_thread, tlist);
+
+ /* resume the read thread */
+ rt_thread_resume(thread);
+ rt_hw_interrupt_enable(level);
+
+ rt_schedule();
+ }
+ else
+ {
+ rt_hw_interrupt_enable(level);
+ }
+ break;
+ }
+ }while (write_nbytes == 0);
+
+ return write_nbytes;
+}
+
+static rt_err_t rt_pipe_control(rt_device_t dev, rt_uint8_t cmd, void *args)
+{
+ return RT_EOK;
+}
+
+rt_err_t rt_pipe_create(const char* name, rt_size_t size)
+{
+ rt_err_t result = RT_EOK;
+ rt_uint8_t* rb_memptr = RT_NULL;
+ struct rt_pipe_device *pipe = RT_NULL;
+
+ /* get aligned size */
+ size = RT_ALIGN(size, RT_ALIGN_SIZE);
+ pipe = (struct rt_pipe_device*) rt_calloc (1, sizeof(struct rt_pipe_device));
+ if (pipe != RT_NULL)
+ {
+ /* create ring buffer of pipe */
+ rb_memptr = rt_malloc(size);
+ if (rb_memptr == RT_NULL)
+ {
+ result = -RT_ENOMEM;
+ goto __exit;
+ }
+ /* initialize suspended list */
+ rt_list_init(&pipe->suspended_read_list);
+ rt_list_init(&pipe->suspended_write_list);
+
+ /* initialize ring buffer */
+ rt_ringbuffer_init(&pipe->ringbuffer, rb_memptr, size);
+
+ /* create device */
+ pipe->parent.type = RT_Device_Class_Char;
+ pipe->parent.init = RT_NULL;
+ pipe->parent.open = RT_NULL;
+ pipe->parent.close = RT_NULL;
+ pipe->parent.read = rt_pipe_read;
+ pipe->parent.write = rt_pipe_write;
+ pipe->parent.control = rt_pipe_control;
+
+ return rt_device_register(&(pipe->parent), name, RT_DEVICE_FLAG_RDWR);
+ }
+ else
+ {
+ result = -RT_ENOMEM;
+ }
+
+__exit:
+ if (pipe != RT_NULL) rt_free(pipe);
+ if (rb_memptr != RT_NULL) rt_free(rb_memptr);
+
+ return result;
+}
+RTM_EXPORT(rt_pipe_create);
+
+void rt_pipe_destroy(struct rt_pipe_device* pipe)
+{
+ if (pipe == RT_NULL) return;
+
+ /* un-register pipe device */
+ rt_device_unregister(&(pipe->parent));
+
+ /* release memory */
+ rt_free(pipe->ringbuffer.buffer_ptr);
+ rt_free(pipe);
+
+ return;
+}
+RTM_EXPORT(rt_pipe_destroy);
+
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