59 lines
1.8 KiB
Text
59 lines
1.8 KiB
Text
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/**
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\defgroup pt Protothreads
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@{
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Protothreads are implemented in a single header file, pt.h, which
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includes the local continuations header file, lc.h. This file in turn
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includes the actual implementation of local continuations, which
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typically also is contained in a single header file.
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*/
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/** @} */
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/**
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\defgroup examples Examples
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@{
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\section example-small A small example
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This first example shows a very simple program: two protothreads
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waiting for each other to toggle two flags. The code illustrates how
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to write protothreads code, how to initialize protothreads, and how to
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schedule them.
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\include example-small.c
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\section example-code-lock A code-lock
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This example shows how to implement a simple code lock - the kind of
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device that is placed next to doors and that you have to push a four
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digit number into in order to unlock the door.
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The code lock waits for key presses from a numeric keyboard and if the
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correct code is entered, the lock is unlocked. There is a maximum time
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of one second between each key press, and after the correct code has
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been entered, no more keys must be pressed for 0.5 seconds before the
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lock is opened.
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\include example-codelock.c
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\section example-buffer The bounded buffer with protothread semaphores
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The following example shows how to implement the bounded buffer
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problem using the protothreads semaphore library. The example uses
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three protothreads: one producer() protothread that produces items,
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one consumer() protothread that consumes items, and one
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driver_thread() that schedules the producer and consumer protothreads.
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Note that there is no need for a mutex to guard the add_to_buffer()
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and get_from_buffer() functions because of the implicit locking
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semantics of protothreads - a protothread will never be preempted and
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will never block except in an explicit PT_WAIT statement.
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\include example-buffer.c
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*/
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/** @} */
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