nsprpub/pr/include/prcmon.h

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  37
  38 #ifndef prcmon_h___
  39 #define prcmon_h___
  40
  41 /*
  42 ** Interface to cached monitors. Cached monitors use an address to find a
  43 ** given PR monitor. In this way a monitor can be associated with another
  44 ** object without preallocating a monitor for all objects.
  45 **
  46 ** A hash table is used to quickly map addresses to individual monitors
  47 ** and the system automatically grows the hash table as needed.
  48 **
  49 ** Cache monitors are about 5 times slower to use than uncached monitors.
  50 */
  51 #include "prmon.h"
  52 #include "prinrval.h"
  53
  54 PR_BEGIN_EXTERN_C
  55
  56 /**
  57 ** Like PR_EnterMonitor except use the "address" to find a monitor in the
  58 ** monitor cache. If successful, returns the PRMonitor now associated
  59 ** with "address". Note that you must PR_CExitMonitor the address to
  60 ** release the monitor cache entry (otherwise the monitor cache will fill
  61 ** up). This call will return NULL if the monitor cache needs to be
  62 ** expanded and the system is out of memory.
  63 */
  64 NSPR_API(PRMonitor*) PR_CEnterMonitor(void *address);
  65
  66 /*
  67 ** Like PR_ExitMonitor except use the "address" to find a monitor in the
  68 ** monitor cache.
  69 */
  70 NSPR_API(PRStatus) PR_CExitMonitor(void *address);
  71
  72 /*
  73 ** Like PR_Wait except use the "address" to find a monitor in the
  74 ** monitor cache.
  75 */
  76 NSPR_API(PRStatus) PR_CWait(void *address, PRIntervalTime timeout);
  77
  78 /*
  79 ** Like PR_Notify except use the "address" to find a monitor in the
  80 ** monitor cache.
  81 */
  82 NSPR_API(PRStatus) PR_CNotify(void *address);
  83
  84 /*
  85 ** Like PR_NotifyAll except use the "address" to find a monitor in the
  86 ** monitor cache.
  87 */
  88 NSPR_API(PRStatus) PR_CNotifyAll(void *address);
  89
  90 /*
  91 ** Set a callback to be invoked each time a monitor is recycled from the cache
  92 ** freelist, with the monitor's cache-key passed in address.
  93 */
  94 NSPR_API(void) PR_CSetOnMonitorRecycle(void (PR_CALLBACK *callback)(void *address));
  95
  96 PR_END_EXTERN_C
  97
  98 #endif /* prcmon_h___ */