1 //----------------------------------------------------------------------
2 // Copyright (C) 2006 - 2007 by the FRESCOR consortium:
4 // Universidad de Cantabria, SPAIN
5 // University of York, UK
6 // Scuola Superiore Sant'Anna, ITALY
7 // Kaiserslautern University, GERMANY
8 // Univ. Politecnica Valencia, SPAIN
9 // Czech Technical University in Prague, CZECH REPUBLIC
11 // Thales Communication S.A. FRANCE
12 // Visual Tools S.A. SPAIN
13 // Rapita Systems Ltd UK
16 // See http://www.frescor.org
18 // The FRESCOR project (FP6/2005/IST/5-034026) is funded
19 // in part by the European Union Sixth Framework Programme
20 // The European Union is not liable of any use that may be
24 // based on previous work (FSF) done in the FIRST project
26 // Copyright (C) 2005 Mälardalen University, SWEDEN
27 // Scuola Superiore S.Anna, ITALY
28 // Universidad de Cantabria, SPAIN
29 // University of York, UK
31 // This file is part of FOSA (Frsh Operating System Abstraction)
33 // FOSA is free software; you can redistribute it and/or modify it
34 // under terms of the GNU General Public License as published by the
35 // Free Software Foundation; either version 2, or (at your option) any
36 // later version. FOSA is distributed in the hope that it will be
37 // useful, but WITHOUT ANY WARRANTY; without even the implied warranty
38 // of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
39 // General Public License for more details. You should have received a
40 // copy of the GNU General Public License along with FOSA; see file
41 // COPYING. If not, write to the Free Software Foundation, 675 Mass Ave,
42 // Cambridge, MA 02139, USA.
44 // As a special exception, including FOSA header files in a file,
45 // instantiating FOSA generics or templates, or linking other files
46 // with FOSA objects to produce an executable application, does not
47 // by itself cause the resulting executable application to be covered
48 // by the GNU General Public License. This exception does not
49 // however invalidate any other reasons why the executable file might be
50 // covered by the GNU Public License.
51 // -----------------------------------------------------------------------
52 //fosa_thread_and_signals.h
53 //==============================================
54 // ******** ****** ******** **********
55 // **///// /** ** **////// /** /**
56 // ** /** ** /** /** /**
57 // ******* /** ** /********* /**********
58 // **//// /** ** ////////** /**//////**
59 // ** /** ** /** /** /**
60 // ** /** ** ******** /** /**
61 // // /******/ //////// // //
63 // FOSA(Frescor Operating System Adaptation layer)
64 //================================================
67 #ifndef FOSA_THREAD_AND_SIGNALS_H_
68 #define FOSA_THREAD_AND_SIGNALS_H_
70 #include "fosa_types.h"
73 * @defgroup threadandsignals Thread and Signals
76 * This module defines the functions that manipulate frsh_threads and
77 * frsh_signals inside FRSH implementation.
79 * Applications can refer to FRSH threads but they cannot create them
80 * directly, instead they must use frsh_thread_create*() which in turn
81 * use fosa_thread_create().
83 * For signals, we assume that the OS provides a direct mapping
84 * for frsh_signal_t and frsh_signal_info_t in the native interface.
91 /*************************
92 * Thread identification
93 *************************/
98 * Compare two thread identifiers to determine if they refer to the
101 bool fosa_thread_equal(frsh_thread_id_t t1, frsh_thread_id_t t2);
107 * Return the thread id of the calling thread
109 frsh_thread_id_t fosa_thread_self();
112 /*************************
113 * Thread creation and termination
114 *************************/
117 * fosa_thread_create()
119 * This function creates a new thread using the attributes specified
120 * in attr. If attr is NULL, default attributes are used. The new
121 * thread starts running immediately, executing the function specified
122 * by code, with an argument equal to arg. Upon successful return, the
123 * variable pointed to by tid will contain the identifier of the newly
124 * created thread. The set of signals that may be synchronously
125 * accepted is inherited from the parent thread.
127 * Returns 0 if successful; otherwise it returs a code error:
129 * FOSA_EAGAIN: the system lacks the necessary resources to create a
130 * new thread or the maximum number of threads has been
133 * FOSA_EINVAL: the value specified by attr is invalid (for instance,
134 * it has not been correctly initialized)
136 * FOSA_EREJECT: the cretion of the thread was rejected by the frsh scheduler
137 * possibly because of incorrect attributes, or because the
138 * requested minimum capacity cannot be guaranteed
141 int fosa_thread_create
142 (frsh_thread_id_t *tid, const frsh_thread_attr_t *attr,
143 frsh_thread_code_t code, void * arg);
147 * Note: no thread termination primitive is provided. The termination
148 * of a thread will be notified by the system to the FRSH scheduler
149 * through the scheduler API
153 /**************************************************
154 * Thread-specific data
155 * (extended with access from a different thread)
157 * Several data items (pointers) may be associated with each thread
158 * Each item is identified through a key, an integer value between 0
159 * and FOSA_MAX_KEYS-1. The caller is responsible of allocating and
160 * deallocating the memory area pointed to by the pointer
161 **************************************************/
166 * Create a new key for thread specific data.
168 * Prior to setting data in a key, we need ask the system to create
169 * one for us. The thread specific data of all the threads is set to
170 * the value NULL until changed to a different value via
171 * fosa_thread_set_specific_data().
173 * @return 0 if successful \n
174 * FOSA_EINVAL If we already have reached the FOSA_MAX_KEYS limit.
175 * FOSA_ENOMEM If there are no enough memory resources to
178 int fosa_key_create(int *key);
185 * This destroys the key and disables its use in the system
187 * @return 0 if successful \n
188 * FOSA_EINVAL The key is not initialised or is not in FOSA key range.
190 int fosa_key_destroy(int key);
194 * fosa_thread_set_specific_data()
196 * Set thread-specific data
198 * For the thread identified by tid, the thread-specifid data field
199 * identified by key will be set to the value specified by value
201 * Returns 0 if successful; otherwise, an error code is returned
202 * FOSA_EINVAL: the value of key is not between 0 and FOSA_MAX_KEYS-1
204 * Alternatively, in case of error the implementation is allowed to
205 * notify it to the system console and then terminate the FRSH
206 * implementation and dependant applications
208 int fosa_thread_set_specific_data
209 (int key, frsh_thread_id_t tid, const void * value);
212 * fosa_thread_get_specific_data()
214 * Get thread-specific data
216 * For the thread identified by tid, the thread-specifid data field
217 * identified by key will be copied to the variable pointed to by value
219 * Returns 0 if successful; otherwise, an error code is returned
220 * FOSA_EINVAL: the value of key is not between 0 and FOSA_MAX_KEYS-1
222 * Alternatively, in case of error the implementation is allowed to
223 * notify it to the system console and then terminate the FRSH
224 * implementation and dependant applications
226 int fosa_thread_get_specific_data(int key, frsh_thread_id_t tid,
230 /******************************************************************
233 * This implementation of FRSH assumes an underlying fixed priority
234 * scheduler with priorities in a range, with a minimum and a
235 * maximumm, a number of priority levels with at least 31
236 * priorities. A larger number implies a larger priority. In systems
237 * in which the underlying scheduler uses the opposite convention, a
238 * mapping is automatically provided by the OS adaptation layer.
239 *******************************************************************/
242 * fosa_get_priority_max()
244 * Return the maximum priority value used in this implementation
246 int fosa_get_priority_max();
249 * fosa_get_priority_min()
251 * Return the minimum priority value used in this implementation
253 int fosa_get_priority_min();
256 * fosa_thread_attr_set_prio()
258 * Change the priority of a thread attributes object
260 * The priority of the thread attriutes object specified by attr is
261 * set to the value specified by prio. This function has no runtime
262 * effect on the priority, except when the attributes object is used
263 * to create a thread, when it will be created with the specified
266 * Returns 0 if successful, or the following error code:
267 * FOSA_EINVAL: the specified priority value is not between the
268 * minimum and the maximum priorities defined in this
269 * FRSH implementation
270 * Alternatively, in case of error the implementation is allowed to
271 * notify it to the system console and then terminate the FRSH
272 * implementation and dependant applications
274 int fosa_thread_attr_set_prio(frsh_thread_attr_t *attr, int prio);
277 * fosa_thread_attr_get_prio()
279 * Get the priority from a thread attributes object
281 * This function sets the variable pointed to by prio to the
282 * priority stored in the thread attributes object attr.
286 int fosa_thread_attr_get_prio
287 (const frsh_thread_attr_t *attr, int *prio);
290 * fosa_thread_set_prio()
292 * Dynamically change the priority of a thread
294 * The priority of the thread identified by tid is
295 * set to the value specified by prio.
297 * Returns 0 if successful, or the following error code:
298 * FOSA_EINVAL: the specified priority value is not between the
299 * minimum and the maximum priorities defined in this
300 * FRSH implementation
301 * Alternatively, in case of error the implementation is allowed to
302 * notify it to the system console and then terminate the FRSH
303 * implementation and dependant applications
305 int fosa_thread_set_prio(frsh_thread_id_t tid, int prio);
308 * fosa_thread_get_prio()
310 * Dynamically get the priority of a thread
312 * This function sets the variable pointed to by prio to the
313 * priority of the thread identified by tid
317 int fosa_thread_get_prio (frsh_thread_id_t tid, int *prio);
321 /*******************************************************************
324 * Signals represent events that may be notified by the system, or
325 * sent explicitly by the application, and for which a thread may
326 * synchronously wait. Signals carry an associated piece of
327 * information (an integer or a pointer) and are queued until they are
328 * accepted. Signals are identified by an integer signal number (of
329 * the type frsh_signal_t) in the range FOSA_SIGNAL_MIN,
330 * FOSA_SIGNAL_MAX. This range is required to have at least <tbd>
332 *******************************************************************/
335 * fosa_set_accepted_signals()
337 * Establish the set of signals that may be synchronously accepted
338 * by the calling thread
340 * The function uses the array of signal numbers specified by set,
341 * which must be of size equal to size
343 * Returns 0 if successful; otherwise it returns an error code:
344 * FOSA_EINVAL: the array contains one or more values which are not
345 * between FOSA_SIGNAL_MIN and FOSA_SIGNAL_MAX, or size
348 * Alternatively, in case of error the implementation is allowed to
349 * notify it to the system console and then terminate the FRSH
350 * implementation and dependant applications
352 int fosa_set_accepted_signals(frsh_signal_t set[], int size);
355 * fosa_signal_queue()
359 * This function is used to explicitly send a signal with a specified
362 * The signal number specified by signal is sent together with the
363 * information specified by info, to the thread identified by
364 * receiver. In those implementations that do not support queueing a
365 * signal with information to a thread (such as POSIX), the signal may
366 * be sent to any thread that is waiting for this signal via
367 * fosa_signal_wait(). Portability can be ensured by having the receiver
368 * thread be the one who is waiting for the signal.
370 * Returns 0 if successful; otherwise it returns an error code:
371 * FOSA_EINVAL: the signal specified by signal is not
372 * between FOSA_SIGNAL_MIN and FOSA_SIGNAL_MAX
374 * FOSA_EAGAIN: no resources are available to queue the signal; the
375 * maximum number of queued signals has been reached, or a
376 * systemwide resource limit has been exceeded
378 * Alternatively, in case of error the implementation is allowed to
379 * notify it to the system console and then terminate the FRSH
380 * implementation and dependant applications
382 int fosa_signal_queue
383 (frsh_signal_t signal, frsh_signal_info_t info,
384 frsh_thread_id_t receiver);
394 * The function waits for the arrival of one of the signals in the
395 * array of signal numbers specified by set, which must be of size
396 * equal to size. If there is a signal already queued, the function
397 * returns immediately. If there is no signal of the specified set
398 * queued, the calling thread is suspended until a signal from that
399 * set arrives. Upon return, if signal_received is not NULL the number
400 * of the signal received is stored in the variable pointed to by
401 * signal_received; and if info is not NULL the associated information
402 * is stored in the variable pointed to by info.
404 * Returns 0 if successful; otherwise it returns an error code:
405 * FOSA_EINVAL: the array contains one or more values which are not
406 * between FOSA_SIGNAL_MIN and FOSA_SIGNAL_MAX, or size
409 * Alternatively, in case of error the implementation is allowed to
410 * notify it to the system console and then terminate the FRSH
411 * implementation and dependant applications
414 (frsh_signal_t set[], int size, frsh_signal_t *signal_received,
415 frsh_signal_info_t *info);
418 * fosa_signal_timedwait()
420 * Timed wait for a signal
422 * This function behaves the same as fosa_signal_wait(), except that
423 * the suspension time is limited to the time interval specified in
424 * the timespec structure referenced by timeout.
426 * Returns 0 if successful; otherwise it returns an error code:
427 * FOSA_EINVAL: the array contains one or more values which are not
428 * between FOSA_SIGNAL_MIN and FOSA_SIGNAL_MAX, or size
429 * is less than 0, or timeout is invalid
430 * FOSA_EAGAIN: The timeout expired
432 * Alternatively, in case of the FOSA_EINVAL error the implementation is
433 * allowed to notify it to the system console and then terminate the
434 * FRSH implementation and dependant applications
436 int fosa_signal_timedwait
437 (frsh_signal_t set[], int size, frsh_signal_t *signal_received,
438 frsh_signal_info_t *info, const struct timespec *timeout);
443 #endif /* !FOSA_THREAD_AND_SIGNALS_H_ */