tinySA/os/rt/src/chregistry.c

176 lines
5.9 KiB
C

/*
ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
2011,2012,2013 Giovanni Di Sirio.
This file is part of ChibiOS/RT.
ChibiOS/RT is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
ChibiOS/RT is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @file chregistry.c
* @brief Threads registry code.
*
* @addtogroup registry
* @details Threads Registry related APIs and services.
*
* <h2>Operation mode</h2>
* The Threads Registry is a double linked list that holds all the
* active threads in the system.<br>
* Operations defined for the registry:
* - <b>First</b>, returns the first, in creation order, active thread
* in the system.
* - <b>Next</b>, returns the next, in creation order, active thread
* in the system.
* .
* The registry is meant to be mainly a debug feature, for example,
* using the registry a debugger can enumerate the active threads
* in any given moment or the shell can print the active threads
* and their state.<br>
* Another possible use is for centralized threads memory management,
* terminating threads can pulse an event source and an event handler
* can perform a scansion of the registry in order to recover the
* memory.
* @pre In order to use the threads registry the @p CH_CFG_USE_REGISTRY
* option must be enabled in @p chconf.h.
* @{
*/
#include "ch.h"
#if CH_CFG_USE_REGISTRY || defined(__DOXYGEN__)
/*===========================================================================*/
/* Module exported variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Module local types. */
/*===========================================================================*/
/*===========================================================================*/
/* Module local variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Module local functions. */
/*===========================================================================*/
#define _offsetof(st, m) \
((size_t)((char *)&((st *)0)->m - (char *)0))
/*===========================================================================*/
/* Module exported functions. */
/*===========================================================================*/
/*
* OS signature in ROM plus debug-related information.
*/
ROMCONST chdebug_t ch_debug = {
"main",
(uint8_t)0,
(uint8_t)sizeof (chdebug_t),
(uint16_t)((CH_KERNEL_MAJOR << 11) |
(CH_KERNEL_MINOR << 6) |
(CH_KERNEL_PATCH) << 0),
(uint8_t)sizeof (void *),
(uint8_t)sizeof (systime_t),
(uint8_t)sizeof (thread_t),
(uint8_t)_offsetof(thread_t, p_prio),
(uint8_t)_offsetof(thread_t, p_ctx),
(uint8_t)_offsetof(thread_t, p_newer),
(uint8_t)_offsetof(thread_t, p_older),
(uint8_t)_offsetof(thread_t, p_name),
#if CH_DBG_ENABLE_STACK_CHECK
(uint8_t)_offsetof(thread_t, p_stklimit),
#else
(uint8_t)0,
#endif
(uint8_t)_offsetof(thread_t, p_state),
(uint8_t)_offsetof(thread_t, p_flags),
#if CH_CFG_USE_DYNAMIC
(uint8_t)_offsetof(thread_t, p_refs),
#else
(uint8_t)0,
#endif
#if CH_CFG_TIME_QUANTUM > 0
(uint8_t)_offsetof(thread_t, p_preempt),
#else
(uint8_t)0,
#endif
#if CH_DBG_THREADS_PROFILING
(uint8_t)_offsetof(thread_t, p_time)
#else
(uint8_t)0
#endif
};
/**
* @brief Returns the first thread in the system.
* @details Returns the most ancient thread in the system, usually this is
* the main thread unless it terminated. A reference is added to the
* returned thread in order to make sure its status is not lost.
* @note This function cannot return @p NULL because there is always at
* least one thread in the system.
*
* @return A reference to the most ancient thread.
*
* @api
*/
thread_t *chRegFirstThread(void) {
thread_t *tp;
chSysLock();
tp = ch.rlist.r_newer;
#if CH_CFG_USE_DYNAMIC
tp->p_refs++;
#endif
chSysUnlock();
return tp;
}
/**
* @brief Returns the thread next to the specified one.
* @details The reference counter of the specified thread is decremented and
* the reference counter of the returned thread is incremented.
*
* @param[in] tp pointer to the thread
* @return A reference to the next thread.
* @retval NULL if there is no next thread.
*
* @api
*/
thread_t *chRegNextThread(thread_t *tp) {
thread_t *ntp;
chSysLock();
ntp = tp->p_newer;
if (ntp == (thread_t *)&ch.rlist)
ntp = NULL;
#if CH_CFG_USE_DYNAMIC
else {
chDbgAssert(ntp->p_refs < 255, "too many references");
ntp->p_refs++;
}
#endif
chSysUnlock();
#if CH_CFG_USE_DYNAMIC
chThdRelease(tp);
#endif
return ntp;
}
#endif /* CH_CFG_USE_REGISTRY */
/** @} */