#ifndef CYGONCE_KERNEL_MUTEX_HXX #define CYGONCE_KERNEL_MUTEX_HXX //========================================================================== // // mutex.hxx // // Mutex class declarations // //========================================================================== // ####ECOSGPLCOPYRIGHTBEGIN#### // ------------------------------------------- // This file is part of eCos, the Embedded Configurable Operating System. // Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc. // // eCos 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 2 or (at your option) any later // version. // // eCos 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 eCos; if not, write to the Free Software Foundation, Inc., // 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. // // As a special exception, if other files instantiate templates or use // macros or inline functions from this file, or you compile this file // and link it with other works to produce a work based on this file, // this file does not by itself cause the resulting work to be covered by // the GNU General Public License. However the source code for this file // must still be made available in accordance with section (3) of the GNU // General Public License v2. // // This exception does not invalidate any other reasons why a work based // on this file might be covered by the GNU General Public License. // ------------------------------------------- // ####ECOSGPLCOPYRIGHTEND#### //========================================================================== //#####DESCRIPTIONBEGIN#### // // Author(s): nickg // Contributors: nickg // Date: 1997-09-09 // Purpose: Define Mutex class interfaces // Description: The classes defined here provide the APIs for mutexes // and condition variables. // Usage: #include // // //####DESCRIPTIONEND#### // //========================================================================== #include #include // assertion macros #include // ------------------------------------------------------------------------- // Mutex. class Cyg_Mutex { friend class Cyg_Condition_Variable; cyg_atomic locked; // true if locked. This may seem // redundant due to "owner" below, // but is intentionally present for // future SMP support. Cyg_Thread *owner; // Current locking thread Cyg_ThreadQueue queue; // Queue of waiting threads #ifdef CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL_DYNAMIC public: enum cyg_protcol { NONE = 0, // no inversion protocol INHERIT, // priority inheritance protocol CEILING // priority ceiling protocol }; private: cyg_protcol protocol; // this mutex's protocol #endif #ifdef CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL_CEILING private: cyg_priority ceiling; // mutex priority ceiling #endif public: CYGDBG_DEFINE_CHECK_THIS Cyg_Mutex(); // Create in unlocked state #ifdef CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL_DYNAMIC Cyg_Mutex( cyg_protcol protocol ); // Create with defined protocol #endif ~Cyg_Mutex(); // Destructor cyg_bool lock(); // lock and/or wait cyg_bool trylock(); // try to lock and return success void unlock(); // unlock void release(); // release all waiting threads // Get the current owning thread inline Cyg_Thread *get_owner() { return owner; } #ifdef CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL_CEILING // set ceiling priority for priority ceiling protocol void set_ceiling( cyg_priority priority ); cyg_priority get_ceiling(void) { return ceiling; }; #endif #ifdef CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL_DYNAMIC // set inversion protocol void set_protocol( cyg_protcol new_protocol ); #endif }; // ------------------------------------------------------------------------- // Condition variable. class Cyg_Condition_Variable { Cyg_Mutex *mutex; // Associated mutex Cyg_ThreadQueue queue; // Queue of waiting threads // Private internal implementation function for wait operations cyg_bool wait_inner( Cyg_Mutex *mutex ); #ifdef CYGMFN_KERNEL_SYNCH_CONDVAR_TIMED_WAIT // Private internal implementation function for timed wait operations cyg_bool wait_inner( Cyg_Mutex *mutex, cyg_tick_count timeout ); #endif public: CYGDBG_DEFINE_CHECK_THIS Cyg_Condition_Variable(); // simple constructor Cyg_Condition_Variable( Cyg_Mutex &mutex // linked mutex ); ~Cyg_Condition_Variable(); // Destructor void signal(); // Set cond true, wake one thread void broadcast(); // Set cond true, wake all threads // Wait for condition to be true inline cyg_bool wait() { return wait_inner( mutex ); } #ifdef CYGMFN_KERNEL_SYNCH_CONDVAR_TIMED_WAIT // Wait until a signal or timeout expiry inline cyg_bool wait( cyg_tick_count timeout ) { return wait_inner( mutex, timeout ); } #endif #ifdef CYGMFN_KERNEL_SYNCH_CONDVAR_WAIT_MUTEX // Wait for condition to be true using the supplied mutex inline cyg_bool wait( Cyg_Mutex &mx ) { return wait_inner( &mx ); } #ifdef CYGMFN_KERNEL_SYNCH_CONDVAR_TIMED_WAIT // Wait until a signal or timeout expiry, using the supplied mutex inline cyg_bool wait( Cyg_Mutex &mx, cyg_tick_count timeout ) { return wait_inner( &mx, timeout ); } #endif #endif // Return a pointer to this variables thread queue. Used mainly // for testing whether a thread is on the queue for a particular // cv. inline Cyg_ThreadQueue *get_queue() { return &queue; }; }; // ------------------------------------------------------------------------- #endif // ifndef CYGONCE_KERNEL_MUTEX_HXX // EOF mutex.hxx