diff options
author | Neo2003 <none@none> | 2008-10-02 16:23:55 -0500 |
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committer | Neo2003 <none@none> | 2008-10-02 16:23:55 -0500 |
commit | 9b1c0e006f20091f28f3f468cfcab1feb51286bd (patch) | |
tree | b5d1ba94a656e6679f8737f9ea6bed1239b73b14 /dep/src/zthread/Status.h |
[svn] * Proper SVN structureinit
--HG--
branch : trunk
Diffstat (limited to 'dep/src/zthread/Status.h')
-rw-r--r-- | dep/src/zthread/Status.h | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/dep/src/zthread/Status.h b/dep/src/zthread/Status.h new file mode 100644 index 00000000000..4735e352861 --- /dev/null +++ b/dep/src/zthread/Status.h @@ -0,0 +1,179 @@ +/* + * Copyright (c) 2005, Eric Crahen + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is furnished + * to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all + * copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + * + */ + +#ifndef __ZTBLOCKINGSTATE_H__ +#define __ZTBLOCKINGSTATE_H__ + +#include <assert.h> + +namespace ZThread { + + /** + * @class Status + * @version 2.3.0 + * + * A Status is associated with each Thread's Monitor. Monitors rely on a + * Status object for providing information that will affect a blocking operations. + */ + class Status { + public: + //! Aggregate of pending status changes + volatile unsigned short _pending; + + //! Interest mask + volatile unsigned short _mask; + + public: + + //! State for the monitor + typedef enum { + + // Default + INVALID = 0x00, + + // Valid states + SIGNALED = 0x01, + INTERRUPTED = 0x02, + TIMEDOUT = 0x04, + CANCELED = 0x08, + + // Mask + ANYTHING = (~INVALID & ~CANCELED) + + } STATE; + + Status() : _pending((unsigned short)INVALID), _mask((unsigned short)ANYTHING) { } + + /** + * Set the mask for the STATE's that next() will report. + * STATE's not covered by the interest mask can still be + * set, they just aren't reported until the mask is changed + * to cover that STATE. + * + * @param STATE + * @pre accessed ONLY by the owning thread. + */ + void interest(STATE mask) { + _mask = static_cast<unsigned short>(mask); + } + + bool masked(STATE mask) { + return (_mask & static_cast<unsigned short>(mask)) == 0; + } + + /** + * Return true if next() will return a STATE covered + * by the current interest mask and by the mask given + * to this function. + * + * @param unsigned short + * @pre accessed ONLY by the owning thread. + */ + bool pending(unsigned short mask) { + + assert(mask != INVALID); + return ((_pending & _mask) & mask) != INVALID; + + } + + /** + * Check the state without the interest mask. + * + * @param state + * @return true if the flag is set + * @pre access must be serial + */ + bool examine(STATE state) { + return (_pending & static_cast<unsigned short>(state)) != INVALID; + } + + /** + * Add the flags to the current state. + * + * @param interest - the flags to add to the current state. + * @pre access must be serial + */ + void push(STATE interest) { + _pending |= interest; + } + + /** + * Clear the flags from the current state + * + * @param interest - the flags to clear from the current state. + * @pre access must be serial + */ + void clear(STATE interest) { + + assert(interest != INVALID); + assert(interest != ANYTHING); + assert(interest != CANCELED); + + _pending &= ~interest; + + } + + /** + * Get the next state from set that has accumulated. The order STATES are + * reported in is SIGNALED, TIMEOUT, or INTERRUPTED. Setting the + * intrest mask allows certain state to be selectively ignored for + * a time - but not lost. The states will become visible again as soon + * as the interest mask is changed appropriately. The interest mask is + * generally used to create uninterruptable waits (waiting for threads + * to start, reacquiring a conditions predicate lock, etc) + * + * @return STATE + * @pre access must be serial + */ + STATE next() { + + STATE state = INVALID; + + if(((_pending & _mask) & SIGNALED) != 0) { + + // Absorb the timeout if it happens when a signal + // is available at the same time + _pending &= ~(SIGNALED|TIMEDOUT); + state = SIGNALED; + + } else if(((_pending & _mask) & TIMEDOUT) != 0) { + + _pending &= ~TIMEDOUT; + state = TIMEDOUT; + + } else if(((_pending & _mask) & INTERRUPTED) != 0) { + + _pending &= ~INTERRUPTED; + state = INTERRUPTED; + + } + + assert(state != INVALID); + return state; + + } + + }; + +}; // namespace ZThread + +#endif |