manu jose / Mbed 2 deprecated proto_thread

4. An implementation of the system as thread(s) written in protothread style, plus additional code that monitors the serial port and touch sensors, and dispatches them to the threads.

Dependencies:   mbed

pt.h@0:3667ad9a98cc, 2010-11-30 (annotated)

Committer:
manujose
Date:
Tue Nov 30 22:02:03 2010 +0000
Revision:
0:3667ad9a98cc
protothreads

Who changed what in which revision?

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manujose 0:3667ad9a98cc 1 /*
manujose 0:3667ad9a98cc 2 * Copyright (c) 2004-2005, Swedish Institute of Computer Science.
manujose 0:3667ad9a98cc 3 * All rights reserved.
manujose 0:3667ad9a98cc 4 *
manujose 0:3667ad9a98cc 5 * Redistribution and use in source and binary forms, with or without
manujose 0:3667ad9a98cc 6 * modification, are permitted provided that the following conditions
manujose 0:3667ad9a98cc 7 * are met:
manujose 0:3667ad9a98cc 8 * 1. Redistributions of source code must retain the above copyright
manujose 0:3667ad9a98cc 9 * notice, this list of conditions and the following disclaimer.
manujose 0:3667ad9a98cc 10 * 2. Redistributions in binary form must reproduce the above copyright
manujose 0:3667ad9a98cc 11 * notice, this list of conditions and the following disclaimer in the
manujose 0:3667ad9a98cc 12 * documentation and/or other materials provided with the distribution.
manujose 0:3667ad9a98cc 13 * 3. Neither the name of the Institute nor the names of its contributors
manujose 0:3667ad9a98cc 14 * may be used to endorse or promote products derived from this software
manujose 0:3667ad9a98cc 15 * without specific prior written permission.
manujose 0:3667ad9a98cc 16 *
manujose 0:3667ad9a98cc 17 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
manujose 0:3667ad9a98cc 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
manujose 0:3667ad9a98cc 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
manujose 0:3667ad9a98cc 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
manujose 0:3667ad9a98cc 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
manujose 0:3667ad9a98cc 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
manujose 0:3667ad9a98cc 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
manujose 0:3667ad9a98cc 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
manujose 0:3667ad9a98cc 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
manujose 0:3667ad9a98cc 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
manujose 0:3667ad9a98cc 27 * SUCH DAMAGE.
manujose 0:3667ad9a98cc 28 *
manujose 0:3667ad9a98cc 29 * This file is part of the Contiki operating system.
manujose 0:3667ad9a98cc 30 *
manujose 0:3667ad9a98cc 31 * Author: Adam Dunkels <adam@sics.se>
manujose 0:3667ad9a98cc 32 *
manujose 0:3667ad9a98cc 33 * $Id: pt.h,v 1.7 2006/10/02 07:52:56 adam Exp $
manujose 0:3667ad9a98cc 34 */
manujose 0:3667ad9a98cc 35
manujose 0:3667ad9a98cc 36 /**
manujose 0:3667ad9a98cc 37 * \addtogroup pt
manujose 0:3667ad9a98cc 38 * @{
manujose 0:3667ad9a98cc 39 */
manujose 0:3667ad9a98cc 40
manujose 0:3667ad9a98cc 41 /**
manujose 0:3667ad9a98cc 42 * \file
manujose 0:3667ad9a98cc 43 * Protothreads implementation.
manujose 0:3667ad9a98cc 44 * \author
manujose 0:3667ad9a98cc 45 * Adam Dunkels <adam@sics.se>
manujose 0:3667ad9a98cc 46 *
manujose 0:3667ad9a98cc 47 */
manujose 0:3667ad9a98cc 48
manujose 0:3667ad9a98cc 49 #ifndef __PT_H__
manujose 0:3667ad9a98cc 50 #define __PT_H__
manujose 0:3667ad9a98cc 51
manujose 0:3667ad9a98cc 52 #include "lc.h"
manujose 0:3667ad9a98cc 53
manujose 0:3667ad9a98cc 54 struct pt {
manujose 0:3667ad9a98cc 55 lc_t lc;
manujose 0:3667ad9a98cc 56 };
manujose 0:3667ad9a98cc 57
manujose 0:3667ad9a98cc 58 #define PT_WAITING 0
manujose 0:3667ad9a98cc 59 #define PT_YIELDED 1
manujose 0:3667ad9a98cc 60 #define PT_EXITED 2
manujose 0:3667ad9a98cc 61 #define PT_ENDED 3
manujose 0:3667ad9a98cc 62
manujose 0:3667ad9a98cc 63 /**
manujose 0:3667ad9a98cc 64 * \name Initialization
manujose 0:3667ad9a98cc 65 * @{
manujose 0:3667ad9a98cc 66 */
manujose 0:3667ad9a98cc 67
manujose 0:3667ad9a98cc 68 /**
manujose 0:3667ad9a98cc 69 * Initialize a protothread.
manujose 0:3667ad9a98cc 70 *
manujose 0:3667ad9a98cc 71 * Initializes a protothread. Initialization must be done prior to
manujose 0:3667ad9a98cc 72 * starting to execute the protothread.
manujose 0:3667ad9a98cc 73 *
manujose 0:3667ad9a98cc 74 * \param pt A pointer to the protothread control structure.
manujose 0:3667ad9a98cc 75 *
manujose 0:3667ad9a98cc 76 * \sa PT_SPAWN()
manujose 0:3667ad9a98cc 77 *
manujose 0:3667ad9a98cc 78 * \hideinitializer
manujose 0:3667ad9a98cc 79 */
manujose 0:3667ad9a98cc 80 #define PT_INIT(pt) LC_INIT((pt)->lc)
manujose 0:3667ad9a98cc 81
manujose 0:3667ad9a98cc 82 /** @} */
manujose 0:3667ad9a98cc 83
manujose 0:3667ad9a98cc 84 /**
manujose 0:3667ad9a98cc 85 * \name Declaration and definition
manujose 0:3667ad9a98cc 86 * @{
manujose 0:3667ad9a98cc 87 */
manujose 0:3667ad9a98cc 88
manujose 0:3667ad9a98cc 89 /**
manujose 0:3667ad9a98cc 90 * Declaration of a protothread.
manujose 0:3667ad9a98cc 91 *
manujose 0:3667ad9a98cc 92 * This macro is used to declare a protothread. All protothreads must
manujose 0:3667ad9a98cc 93 * be declared with this macro.
manujose 0:3667ad9a98cc 94 *
manujose 0:3667ad9a98cc 95 * \param name_args The name and arguments of the C function
manujose 0:3667ad9a98cc 96 * implementing the protothread.
manujose 0:3667ad9a98cc 97 *
manujose 0:3667ad9a98cc 98 * \hideinitializer
manujose 0:3667ad9a98cc 99 */
manujose 0:3667ad9a98cc 100 #define PT_THREAD(name_args) char name_args
manujose 0:3667ad9a98cc 101
manujose 0:3667ad9a98cc 102 /**
manujose 0:3667ad9a98cc 103 * Declare the start of a protothread inside the C function
manujose 0:3667ad9a98cc 104 * implementing the protothread.
manujose 0:3667ad9a98cc 105 *
manujose 0:3667ad9a98cc 106 * This macro is used to declare the starting point of a
manujose 0:3667ad9a98cc 107 * protothread. It should be placed at the start of the function in
manujose 0:3667ad9a98cc 108 * which the protothread runs. All C statements above the PT_BEGIN()
manujose 0:3667ad9a98cc 109 * invokation will be executed each time the protothread is scheduled.
manujose 0:3667ad9a98cc 110 *
manujose 0:3667ad9a98cc 111 * \param pt A pointer to the protothread control structure.
manujose 0:3667ad9a98cc 112 *
manujose 0:3667ad9a98cc 113 * \hideinitializer
manujose 0:3667ad9a98cc 114 */
manujose 0:3667ad9a98cc 115 #define PT_BEGIN(pt) { char PT_YIELD_FLAG = 1; LC_RESUME((pt)->lc)
manujose 0:3667ad9a98cc 116
manujose 0:3667ad9a98cc 117 /**
manujose 0:3667ad9a98cc 118 * Declare the end of a protothread.
manujose 0:3667ad9a98cc 119 *
manujose 0:3667ad9a98cc 120 * This macro is used for declaring that a protothread ends. It must
manujose 0:3667ad9a98cc 121 * always be used together with a matching PT_BEGIN() macro.
manujose 0:3667ad9a98cc 122 *
manujose 0:3667ad9a98cc 123 * \param pt A pointer to the protothread control structure.
manujose 0:3667ad9a98cc 124 *
manujose 0:3667ad9a98cc 125 * \hideinitializer
manujose 0:3667ad9a98cc 126 */
manujose 0:3667ad9a98cc 127 #define PT_END(pt) LC_END((pt)->lc); PT_YIELD_FLAG = 0; \
manujose 0:3667ad9a98cc 128 PT_INIT(pt); return PT_ENDED; }
manujose 0:3667ad9a98cc 129
manujose 0:3667ad9a98cc 130 /** @} */
manujose 0:3667ad9a98cc 131
manujose 0:3667ad9a98cc 132 /**
manujose 0:3667ad9a98cc 133 * \name Blocked wait
manujose 0:3667ad9a98cc 134 * @{
manujose 0:3667ad9a98cc 135 */
manujose 0:3667ad9a98cc 136
manujose 0:3667ad9a98cc 137 /**
manujose 0:3667ad9a98cc 138 * Block and wait until condition is true.
manujose 0:3667ad9a98cc 139 *
manujose 0:3667ad9a98cc 140 * This macro blocks the protothread until the specified condition is
manujose 0:3667ad9a98cc 141 * true.
manujose 0:3667ad9a98cc 142 *
manujose 0:3667ad9a98cc 143 * \param pt A pointer to the protothread control structure.
manujose 0:3667ad9a98cc 144 * \param condition The condition.
manujose 0:3667ad9a98cc 145 *
manujose 0:3667ad9a98cc 146 * \hideinitializer
manujose 0:3667ad9a98cc 147 */
manujose 0:3667ad9a98cc 148 #define PT_WAIT_UNTIL(pt, condition) \
manujose 0:3667ad9a98cc 149 do { \
manujose 0:3667ad9a98cc 150 LC_SET((pt)->lc); \
manujose 0:3667ad9a98cc 151 if(!(condition)) { \
manujose 0:3667ad9a98cc 152 return PT_WAITING; \
manujose 0:3667ad9a98cc 153 } \
manujose 0:3667ad9a98cc 154 } while(0)
manujose 0:3667ad9a98cc 155
manujose 0:3667ad9a98cc 156 /**
manujose 0:3667ad9a98cc 157 * Block and wait while condition is true.
manujose 0:3667ad9a98cc 158 *
manujose 0:3667ad9a98cc 159 * This function blocks and waits while condition is true. See
manujose 0:3667ad9a98cc 160 * PT_WAIT_UNTIL().
manujose 0:3667ad9a98cc 161 *
manujose 0:3667ad9a98cc 162 * \param pt A pointer to the protothread control structure.
manujose 0:3667ad9a98cc 163 * \param cond The condition.
manujose 0:3667ad9a98cc 164 *
manujose 0:3667ad9a98cc 165 * \hideinitializer
manujose 0:3667ad9a98cc 166 */
manujose 0:3667ad9a98cc 167 #define PT_WAIT_WHILE(pt, cond) PT_WAIT_UNTIL((pt), !(cond))
manujose 0:3667ad9a98cc 168
manujose 0:3667ad9a98cc 169 /** @} */
manujose 0:3667ad9a98cc 170
manujose 0:3667ad9a98cc 171 /**
manujose 0:3667ad9a98cc 172 * \name Hierarchical protothreads
manujose 0:3667ad9a98cc 173 * @{
manujose 0:3667ad9a98cc 174 */
manujose 0:3667ad9a98cc 175
manujose 0:3667ad9a98cc 176 /**
manujose 0:3667ad9a98cc 177 * Block and wait until a child protothread completes.
manujose 0:3667ad9a98cc 178 *
manujose 0:3667ad9a98cc 179 * This macro schedules a child protothread. The current protothread
manujose 0:3667ad9a98cc 180 * will block until the child protothread completes.
manujose 0:3667ad9a98cc 181 *
manujose 0:3667ad9a98cc 182 * \note The child protothread must be manually initialized with the
manujose 0:3667ad9a98cc 183 * PT_INIT() function before this function is used.
manujose 0:3667ad9a98cc 184 *
manujose 0:3667ad9a98cc 185 * \param pt A pointer to the protothread control structure.
manujose 0:3667ad9a98cc 186 * \param thread The child protothread with arguments
manujose 0:3667ad9a98cc 187 *
manujose 0:3667ad9a98cc 188 * \sa PT_SPAWN()
manujose 0:3667ad9a98cc 189 *
manujose 0:3667ad9a98cc 190 * \hideinitializer
manujose 0:3667ad9a98cc 191 */
manujose 0:3667ad9a98cc 192 #define PT_WAIT_THREAD(pt, thread) PT_WAIT_WHILE((pt), PT_SCHEDULE(thread))
manujose 0:3667ad9a98cc 193
manujose 0:3667ad9a98cc 194 /**
manujose 0:3667ad9a98cc 195 * Spawn a child protothread and wait until it exits.
manujose 0:3667ad9a98cc 196 *
manujose 0:3667ad9a98cc 197 * This macro spawns a child protothread and waits until it exits. The
manujose 0:3667ad9a98cc 198 * macro can only be used within a protothread.
manujose 0:3667ad9a98cc 199 *
manujose 0:3667ad9a98cc 200 * \param pt A pointer to the protothread control structure.
manujose 0:3667ad9a98cc 201 * \param child A pointer to the child protothread's control structure.
manujose 0:3667ad9a98cc 202 * \param thread The child protothread with arguments
manujose 0:3667ad9a98cc 203 *
manujose 0:3667ad9a98cc 204 * \hideinitializer
manujose 0:3667ad9a98cc 205 */
manujose 0:3667ad9a98cc 206 #define PT_SPAWN(pt, child, thread) \
manujose 0:3667ad9a98cc 207 do { \
manujose 0:3667ad9a98cc 208 PT_INIT((child)); \
manujose 0:3667ad9a98cc 209 PT_WAIT_THREAD((pt), (thread)); \
manujose 0:3667ad9a98cc 210 } while(0)
manujose 0:3667ad9a98cc 211
manujose 0:3667ad9a98cc 212 /** @} */
manujose 0:3667ad9a98cc 213
manujose 0:3667ad9a98cc 214 /**
manujose 0:3667ad9a98cc 215 * \name Exiting and restarting
manujose 0:3667ad9a98cc 216 * @{
manujose 0:3667ad9a98cc 217 */
manujose 0:3667ad9a98cc 218
manujose 0:3667ad9a98cc 219 /**
manujose 0:3667ad9a98cc 220 * Restart the protothread.
manujose 0:3667ad9a98cc 221 *
manujose 0:3667ad9a98cc 222 * This macro will block and cause the running protothread to restart
manujose 0:3667ad9a98cc 223 * its execution at the place of the PT_BEGIN() call.
manujose 0:3667ad9a98cc 224 *
manujose 0:3667ad9a98cc 225 * \param pt A pointer to the protothread control structure.
manujose 0:3667ad9a98cc 226 *
manujose 0:3667ad9a98cc 227 * \hideinitializer
manujose 0:3667ad9a98cc 228 */
manujose 0:3667ad9a98cc 229 #define PT_RESTART(pt) \
manujose 0:3667ad9a98cc 230 do { \
manujose 0:3667ad9a98cc 231 PT_INIT(pt); \
manujose 0:3667ad9a98cc 232 return PT_WAITING; \
manujose 0:3667ad9a98cc 233 } while(0)
manujose 0:3667ad9a98cc 234
manujose 0:3667ad9a98cc 235 /**
manujose 0:3667ad9a98cc 236 * Exit the protothread.
manujose 0:3667ad9a98cc 237 *
manujose 0:3667ad9a98cc 238 * This macro causes the protothread to exit. If the protothread was
manujose 0:3667ad9a98cc 239 * spawned by another protothread, the parent protothread will become
manujose 0:3667ad9a98cc 240 * unblocked and can continue to run.
manujose 0:3667ad9a98cc 241 *
manujose 0:3667ad9a98cc 242 * \param pt A pointer to the protothread control structure.
manujose 0:3667ad9a98cc 243 *
manujose 0:3667ad9a98cc 244 * \hideinitializer
manujose 0:3667ad9a98cc 245 */
manujose 0:3667ad9a98cc 246 #define PT_EXIT(pt) \
manujose 0:3667ad9a98cc 247 do { \
manujose 0:3667ad9a98cc 248 PT_INIT(pt); \
manujose 0:3667ad9a98cc 249 return PT_EXITED; \
manujose 0:3667ad9a98cc 250 } while(0)
manujose 0:3667ad9a98cc 251
manujose 0:3667ad9a98cc 252 /** @} */
manujose 0:3667ad9a98cc 253
manujose 0:3667ad9a98cc 254 /**
manujose 0:3667ad9a98cc 255 * \name Calling a protothread
manujose 0:3667ad9a98cc 256 * @{
manujose 0:3667ad9a98cc 257 */
manujose 0:3667ad9a98cc 258
manujose 0:3667ad9a98cc 259 /**
manujose 0:3667ad9a98cc 260 * Schedule a protothread.
manujose 0:3667ad9a98cc 261 *
manujose 0:3667ad9a98cc 262 * This function shedules a protothread. The return value of the
manujose 0:3667ad9a98cc 263 * function is non-zero if the protothread is running or zero if the
manujose 0:3667ad9a98cc 264 * protothread has exited.
manujose 0:3667ad9a98cc 265 *
manujose 0:3667ad9a98cc 266 * \param f The call to the C function implementing the protothread to
manujose 0:3667ad9a98cc 267 * be scheduled
manujose 0:3667ad9a98cc 268 *
manujose 0:3667ad9a98cc 269 * \hideinitializer
manujose 0:3667ad9a98cc 270 */
manujose 0:3667ad9a98cc 271 #define PT_SCHEDULE(f) ((f) < PT_EXITED)
manujose 0:3667ad9a98cc 272
manujose 0:3667ad9a98cc 273 /** @} */
manujose 0:3667ad9a98cc 274
manujose 0:3667ad9a98cc 275 /**
manujose 0:3667ad9a98cc 276 * \name Yielding from a protothread
manujose 0:3667ad9a98cc 277 * @{
manujose 0:3667ad9a98cc 278 */
manujose 0:3667ad9a98cc 279
manujose 0:3667ad9a98cc 280 /**
manujose 0:3667ad9a98cc 281 * Yield from the current protothread.
manujose 0:3667ad9a98cc 282 *
manujose 0:3667ad9a98cc 283 * This function will yield the protothread, thereby allowing other
manujose 0:3667ad9a98cc 284 * processing to take place in the system.
manujose 0:3667ad9a98cc 285 *
manujose 0:3667ad9a98cc 286 * \param pt A pointer to the protothread control structure.
manujose 0:3667ad9a98cc 287 *
manujose 0:3667ad9a98cc 288 * \hideinitializer
manujose 0:3667ad9a98cc 289 */
manujose 0:3667ad9a98cc 290 #define PT_YIELD(pt) \
manujose 0:3667ad9a98cc 291 do { \
manujose 0:3667ad9a98cc 292 PT_YIELD_FLAG = 0; \
manujose 0:3667ad9a98cc 293 LC_SET((pt)->lc); \
manujose 0:3667ad9a98cc 294 if(PT_YIELD_FLAG == 0) { \
manujose 0:3667ad9a98cc 295 return PT_YIELDED; \
manujose 0:3667ad9a98cc 296 } \
manujose 0:3667ad9a98cc 297 } while(0)
manujose 0:3667ad9a98cc 298
manujose 0:3667ad9a98cc 299 /**
manujose 0:3667ad9a98cc 300 * \brief Yield from the protothread until a condition occurs.
manujose 0:3667ad9a98cc 301 * \param pt A pointer to the protothread control structure.
manujose 0:3667ad9a98cc 302 * \param cond The condition.
manujose 0:3667ad9a98cc 303 *
manujose 0:3667ad9a98cc 304 * This function will yield the protothread, until the
manujose 0:3667ad9a98cc 305 * specified condition evaluates to true.
manujose 0:3667ad9a98cc 306 *
manujose 0:3667ad9a98cc 307 *
manujose 0:3667ad9a98cc 308 * \hideinitializer
manujose 0:3667ad9a98cc 309 */
manujose 0:3667ad9a98cc 310 #define PT_YIELD_UNTIL(pt, cond) \
manujose 0:3667ad9a98cc 311 do { \
manujose 0:3667ad9a98cc 312 PT_YIELD_FLAG = 0; \
manujose 0:3667ad9a98cc 313 LC_SET((pt)->lc); \
manujose 0:3667ad9a98cc 314 if((PT_YIELD_FLAG == 0) || !(cond)) { \
manujose 0:3667ad9a98cc 315 return PT_YIELDED; \
manujose 0:3667ad9a98cc 316 } \
manujose 0:3667ad9a98cc 317 } while(0)
manujose 0:3667ad9a98cc 318
manujose 0:3667ad9a98cc 319 /** @} */
manujose 0:3667ad9a98cc 320
manujose 0:3667ad9a98cc 321 #endif /* __PT_H__ */
manujose 0:3667ad9a98cc 322
manujose 0:3667ad9a98cc 323 /** @} */