The Tor Browser: nsprpub/pr/include/md/_pth.h@44a2da4a2ab2 (annotated)

nsprpub/pr/include/md/_pth.h@44a2da4a2ab2 (annotated)

nsprpub/pr/include/md/_pth.h

Fri, 16 Jan 2015 04:50:19 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Fri, 16 Jan 2015 04:50:19 +0100
branch: TOR_BUG_9701
changeset 13: 44a2da4a2ab2
permissions: -rw-r--r--

Replace accessor implementation with direct member state manipulation, by
request https://trac.torproject.org/projects/tor/ticket/9701#comment:32

 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 #ifndef nspr_pth_defs_h_
 #define nspr_pth_defs_h_
 /*
 ** Appropriate definitions of entry points not used in a pthreads world
 */
 #define _PR_MD_BLOCK_CLOCK_INTERRUPTS()
 #define _PR_MD_UNBLOCK_CLOCK_INTERRUPTS()
 #define _PR_MD_DISABLE_CLOCK_INTERRUPTS()
 #define _PR_MD_ENABLE_CLOCK_INTERRUPTS()
 /* In good standards fashion, the DCE threads (based on posix-4) are not
  * quite the same as newer posix implementations.  These are mostly name
  * changes and small differences, so macros usually do the trick
  */
 #ifdef _PR_DCETHREADS
 #define _PT_PTHREAD_MUTEXATTR_INIT        pthread_mutexattr_create
 #define _PT_PTHREAD_MUTEXATTR_DESTROY     pthread_mutexattr_delete
 #define _PT_PTHREAD_MUTEX_INIT(m, a)      pthread_mutex_init(&(m), a)
 #define _PT_PTHREAD_MUTEX_IS_LOCKED(m)    (0 == pthread_mutex_trylock(&(m)))
 #define _PT_PTHREAD_CONDATTR_INIT         pthread_condattr_create
 #define _PT_PTHREAD_COND_INIT(m, a)       pthread_cond_init(&(m), a)
 #define _PT_PTHREAD_CONDATTR_DESTROY      pthread_condattr_delete
 /* Notes about differences between DCE threads and pthreads 10:
  *   1. pthread_mutex_trylock returns 1 when it locks the mutex
  *      0 when it does not.  The latest pthreads has a set of errno-like
  *      return values.
  *   2. return values from pthread_cond_timedwait are different.
  *
  *
  *
  */
 #elif defined(BSDI)
 /*
  * Mutex and condition attributes are not supported.  The attr
  * argument to pthread_mutex_init() and pthread_cond_init() must
  * be passed as NULL.
  *
  * The memset calls in _PT_PTHREAD_MUTEX_INIT and _PT_PTHREAD_COND_INIT
  * are to work around BSDI's using a single bit to indicate a mutex
  * or condition variable is initialized.  This entire BSDI section
  * will go away when BSDI releases updated threads libraries for
  * BSD/OS 3.1 and 4.0.
  */
 #define _PT_PTHREAD_MUTEXATTR_INIT(x)     0
 #define _PT_PTHREAD_MUTEXATTR_DESTROY(x)  /* */
 #define _PT_PTHREAD_MUTEX_INIT(m, a)      (memset(&(m), 0, sizeof(m)), \
                                       pthread_mutex_init(&(m), NULL))
 #define _PT_PTHREAD_MUTEX_IS_LOCKED(m)    (EBUSY == pthread_mutex_trylock(&(m)))
 #define _PT_PTHREAD_CONDATTR_INIT(x)      0
 #define _PT_PTHREAD_CONDATTR_DESTROY(x)   /* */
 #define _PT_PTHREAD_COND_INIT(m, a)       (memset(&(m), 0, sizeof(m)), \
                                       pthread_cond_init(&(m), NULL))
 #else
 #define _PT_PTHREAD_MUTEXATTR_INIT        pthread_mutexattr_init
 #define _PT_PTHREAD_MUTEXATTR_DESTROY     pthread_mutexattr_destroy
 #define _PT_PTHREAD_MUTEX_INIT(m, a)      pthread_mutex_init(&(m), &(a))
 #if defined(FREEBSD)
 #define _PT_PTHREAD_MUTEX_IS_LOCKED(m)    pt_pthread_mutex_is_locked(&(m))
 #else
 #define _PT_PTHREAD_MUTEX_IS_LOCKED(m)    (EBUSY == pthread_mutex_trylock(&(m)))
 #endif
 #if defined(ANDROID)
 /* Conditional attribute init and destroy aren't implemented in bionic. */
 #define _PT_PTHREAD_CONDATTR_INIT(x)      0
 #define _PT_PTHREAD_CONDATTR_DESTROY(x)   /* */
 #else
 #define _PT_PTHREAD_CONDATTR_INIT         pthread_condattr_init
 #define _PT_PTHREAD_CONDATTR_DESTROY      pthread_condattr_destroy
 #endif
 #define _PT_PTHREAD_COND_INIT(m, a)       pthread_cond_init(&(m), &(a))
 #endif
 /* The pthreads standard does not specify an invalid value for the
  * pthread_t handle.  (0 is usually an invalid pthread identifier
  * but there are exceptions, for example, DG/UX.)  These macros
  * define a way to set the handle to or compare the handle with an
  * invalid identifier.  These macros are not portable and may be
  * more of a problem as we adapt to more pthreads implementations.
  * They are only used in the PRMonitor functions.  Do not use them
  * in new code.
  *
  * Unfortunately some of our clients depend on certain properties
  * of our PRMonitor implementation, preventing us from replacing
  * it by a portable implementation.
  * - High-performance servers like the fact that PR_EnterMonitor
  *   only calls PR_Lock and PR_ExitMonitor only calls PR_Unlock.
  *   (A portable implementation would use a PRLock and a PRCondVar
  *   to implement the recursive lock in a monitor and call both
  *   PR_Lock and PR_Unlock in PR_EnterMonitor and PR_ExitMonitor.)
  *   Unfortunately this forces us to read the monitor owner field
  *   without holding a lock.
  * - One way to make it safe to read the monitor owner field
  *   without holding a lock is to make that field a PRThread*
  *   (one should be able to read a pointer with a single machine
  *   instruction).  However, PR_GetCurrentThread calls calloc if
  *   it is called by a thread that was not created by NSPR.  The
  *   malloc tracing tools in the Mozilla client use PRMonitor for
  *   locking in their malloc, calloc, and free functions.  If
  *   PR_EnterMonitor calls any of these functions, infinite
  *   recursion ensues.
  */
 #if defined(_PR_DCETHREADS)
 #define _PT_PTHREAD_INVALIDATE_THR_HANDLE(t) \
 	memset(&(t), 0, sizeof(pthread_t))
 #define _PT_PTHREAD_THR_HANDLE_IS_INVALID(t) \
 	(!memcmp(&(t), &pt_zero_tid, sizeof(pthread_t)))
 #define _PT_PTHREAD_COPY_THR_HANDLE(st, dt)   (dt) = (st)
 #elif defined(IRIX) || defined(OSF1) || defined(AIX) || defined(SOLARIS) \
 	|| defined(LINUX) || defined(__GNU__) || defined(__GLIBC__) \
 	|| defined(HPUX) || defined(FREEBSD) \
 	|| defined(NETBSD) || defined(OPENBSD) || defined(BSDI) \
 	|| defined(NTO) || defined(DARWIN) \
 	|| defined(UNIXWARE) || defined(RISCOS)	|| defined(SYMBIAN)
 #define _PT_PTHREAD_INVALIDATE_THR_HANDLE(t)  (t) = 0
 #define _PT_PTHREAD_THR_HANDLE_IS_INVALID(t)  (t) == 0
 #define _PT_PTHREAD_COPY_THR_HANDLE(st, dt)   (dt) = (st)
 #else
 #error "pthreads is not supported for this architecture"
 #endif
 #if defined(_PR_DCETHREADS)
 #define _PT_PTHREAD_ATTR_INIT            pthread_attr_create
 #define _PT_PTHREAD_ATTR_DESTROY         pthread_attr_delete
 #define _PT_PTHREAD_CREATE(t, a, f, r)   pthread_create(t, a, f, r)
 #define _PT_PTHREAD_KEY_CREATE           pthread_keycreate
 #define _PT_PTHREAD_ATTR_SETSCHEDPOLICY  pthread_attr_setsched
 #define _PT_PTHREAD_ATTR_GETSTACKSIZE(a, s) \
                                      (*(s) = pthread_attr_getstacksize(*(a)), 0)
 #define _PT_PTHREAD_GETSPECIFIC(k, r) \
 		pthread_getspecific((k), (pthread_addr_t *) &(r))
 #elif defined(_PR_PTHREADS)
 #define _PT_PTHREAD_ATTR_INIT            pthread_attr_init
 #define _PT_PTHREAD_ATTR_DESTROY         pthread_attr_destroy
 #define _PT_PTHREAD_CREATE(t, a, f, r)   pthread_create(t, &a, f, r)
 #define _PT_PTHREAD_KEY_CREATE           pthread_key_create
 #define _PT_PTHREAD_ATTR_SETSCHEDPOLICY  pthread_attr_setschedpolicy
 #define _PT_PTHREAD_ATTR_GETSTACKSIZE(a, s) pthread_attr_getstacksize(a, s)
 #define _PT_PTHREAD_GETSPECIFIC(k, r)    (r) = pthread_getspecific(k)
 #else
 #error "Cannot determine pthread strategy"
 #endif
 #if defined(_PR_DCETHREADS)
 #define _PT_PTHREAD_EXPLICIT_SCHED      _PT_PTHREAD_DEFAULT_SCHED
 #endif
 /*
  * pthread_mutex_trylock returns different values in DCE threads and
  * pthreads.
  */
 #if defined(_PR_DCETHREADS)
 #define PT_TRYLOCK_SUCCESS 1
 #define PT_TRYLOCK_BUSY    0
 #else
 #define PT_TRYLOCK_SUCCESS 0
 #define PT_TRYLOCK_BUSY    EBUSY
 #endif
 /*
  * These platforms don't have sigtimedwait()
  */
 #if (defined(AIX) && !defined(AIX4_3_PLUS)) \
 	|| defined(LINUX) || defined(__GNU__)|| defined(__GLIBC__) \
 	|| defined(FREEBSD) || defined(NETBSD) || defined(OPENBSD) \
 	|| defined(BSDI) || defined(UNIXWARE) \
 	|| defined(DARWIN) || defined(SYMBIAN)
 #define PT_NO_SIGTIMEDWAIT
 #endif
 #if defined(OSF1)
 #define PT_PRIO_MIN            PRI_OTHER_MIN
 #define PT_PRIO_MAX            PRI_OTHER_MAX
 #elif defined(IRIX)
 #include <sys/sched.h>
 #define PT_PRIO_MIN            PX_PRIO_MIN
 #define PT_PRIO_MAX            PX_PRIO_MAX
 #elif defined(AIX)
 #include <sys/priv.h>
 #include <sys/sched.h>
 #ifndef PTHREAD_CREATE_JOINABLE
 #define PTHREAD_CREATE_JOINABLE     PTHREAD_CREATE_UNDETACHED
 #endif
 #define PT_PRIO_MIN            DEFAULT_PRIO
 #define PT_PRIO_MAX            DEFAULT_PRIO
 #elif defined(HPUX)
 #if defined(_PR_DCETHREADS)
 #define PT_PRIO_MIN            PRI_OTHER_MIN
 #define PT_PRIO_MAX            PRI_OTHER_MAX
 #else /* defined(_PR_DCETHREADS) */
 #include <sys/sched.h>
 #define PT_PRIO_MIN            sched_get_priority_min(SCHED_OTHER)
 #define PT_PRIO_MAX            sched_get_priority_max(SCHED_OTHER)
 #endif /* defined(_PR_DCETHREADS) */
 #elif defined(LINUX) || defined(__GNU__) || defined(__GLIBC__) \
 	|| defined(FREEBSD) || defined(SYMBIAN)
 #define PT_PRIO_MIN            sched_get_priority_min(SCHED_OTHER)
 #define PT_PRIO_MAX            sched_get_priority_max(SCHED_OTHER)
 #elif defined(NTO)
 /*
  * Neutrino has functions that return the priority range but
  * they return invalid numbers, so I just hard coded these here
  * for now.  Jerry.Kirk@Nexarecorp.com
  */
 #define PT_PRIO_MIN            0
 #define PT_PRIO_MAX            30
 #elif defined(SOLARIS)
 /*
  * Solaris doesn't seem to have macros for the min/max priorities.
  * The range of 0-127 is mentioned in the pthread_setschedparam(3T)
  * man pages, and pthread_setschedparam indeed allows 0-127.  However,
  * pthread_attr_setschedparam does not allow 0; it allows 1-127.
  */
 #define PT_PRIO_MIN            1
 #define PT_PRIO_MAX            127
 #elif defined(OPENBSD)
 #define PT_PRIO_MIN            0
 #define PT_PRIO_MAX            31
 #elif defined(NETBSD) \
 	|| defined(BSDI) || defined(DARWIN) || defined(UNIXWARE) \
 	|| defined(RISCOS) /* XXX */
 #define PT_PRIO_MIN            0
 #define PT_PRIO_MAX            126
 #else
 #error "pthreads is not supported for this architecture"
 #endif
 /*
  * The _PT_PTHREAD_YIELD function is called from a signal handler.
  * Needed for garbage collection -- Look at PR_Suspend/PR_Resume
  * implementation.
  */
 #if defined(_PR_DCETHREADS)
 #define _PT_PTHREAD_YIELD()            	pthread_yield()
 #elif defined(OSF1)
 /*
  * sched_yield can't be called from a signal handler.  Must use
  * the _np version.
  */
 #define _PT_PTHREAD_YIELD()            	pthread_yield_np()
 #elif defined(AIX)
 extern int (*_PT_aix_yield_fcn)();
 #define _PT_PTHREAD_YIELD()			(*_PT_aix_yield_fcn)()
 #elif defined(IRIX)
 #include <time.h>
 #define _PT_PTHREAD_YIELD() \
     PR_BEGIN_MACRO               				\
 		struct timespec onemillisec = {0};		\
 		onemillisec.tv_nsec = 1000000L;			\
         nanosleep(&onemillisec,NULL);			\
     PR_END_MACRO
 #elif defined(HPUX) || defined(SOLARIS) \
 	|| defined(LINUX) || defined(__GNU__) || defined(__GLIBC__) \
 	|| defined(FREEBSD) || defined(NETBSD) || defined(OPENBSD) \
 	|| defined(BSDI) || defined(NTO) || defined(DARWIN) \
 	|| defined(UNIXWARE) || defined(RISCOS) || defined(SYMBIAN)
 #define _PT_PTHREAD_YIELD()            	sched_yield()
 #else
 #error "Need to define _PT_PTHREAD_YIELD for this platform"
 #endif
 #endif /* nspr_pth_defs_h_ */

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nsprpub/pr/include/md/_pth.h@44a2da4a2ab2 (annotated)

nsprpub/pr/include/md/_pth.h