X-Git-Url: https://perl5.git.perl.org/perl5.git/blobdiff_plain/38a03e6ea6b9b346c41b9006fbeedc3b0f0130b2..9f61520b6458f5163a51ae6309a604a15d92771a:/thread.h

diff --git a/thread.h b/thread.h
index 79064e4..9740dba 100644
--- a/thread.h
+++ b/thread.h
@@ -1,237 +1,297 @@
-#ifdef USE_THREADS
+#if defined(USE_THREADS) || defined(USE_ITHREADS)
 
 #ifdef WIN32
-#  include "win32/win32thread.h"
-#endif
-
-/* POSIXish threads */
-typedef pthread_t perl_thread;
-#ifdef OLD_PTHREADS_API
-#  define pthread_mutexattr_init(a) pthread_mutexattr_create(a)
-#  define pthread_mutexattr_settype(a,t) pthread_mutexattr_setkind_np(a,t)
-#  define pthread_key_create(k,d) pthread_keycreate(k,(pthread_destructor_t)(d))
-#  define YIELD pthread_yield()
-#  define DETACH(t)				\
-    STMT_START {				\
-	if (pthread_detach(&(t)->self)) {	\
-	    MUTEX_UNLOCK(&(t)->mutex);		\
-	    croak("panic: DETACH");		\
-	}					\
-    } STMT_END
+#  include <win32thread.h>
 #else
-#  define pthread_mutexattr_default NULL
-#  define pthread_condattr_default NULL
-#  define pthread_attr_default NULL
-#endif /* OLD_PTHREADS_API */
+#  ifdef OLD_PTHREADS_API /* Here be dragons. */
+#    define DETACH(t) \
+    STMT_START {						\
+	if (pthread_detach(&(t)->self)) {			\
+	    MUTEX_UNLOCK(&(t)->mutex);				\
+	    Perl_croak_nocontext("panic: DETACH");		\
+	}							\
+    } STMT_END
+
+#    define PERL_GET_CONTEXT	Perl_get_context()
+#    define PERL_SET_CONTEXT(t)	Perl_set_context((void*)t)
+
+#    define PTHREAD_GETSPECIFIC_INT
+#    ifdef DJGPP
+#      define pthread_addr_t any_t
+#      define NEED_PTHREAD_INIT
+#      define PTHREAD_CREATE_JOINABLE (1)
+#    endif
+#    ifdef __OPEN_VM
+#      define pthread_addr_t void *
+#    endif
+#    ifdef VMS
+#      define pthread_attr_init(a) pthread_attr_create(a)
+#      define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_setdetach_np(a,s)
+#      define PTHREAD_CREATE(t,a,s,d) pthread_create(t,a,s,d)
+#      define pthread_key_create(k,d) pthread_keycreate(k,(pthread_destructor_t)(d))
+#      define pthread_mutexattr_init(a) pthread_mutexattr_create(a)
+#      define pthread_mutexattr_settype(a,t) pthread_mutexattr_setkind_np(a,t)
+#    endif
+#    if defined(DJGPP) || defined(__OPEN_VM)
+#      define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_attr_setdetachstate(a,&(s))
+#      define YIELD pthread_yield(NULL)
+#    endif
+#  endif
+#    define pthread_mutexattr_default NULL
+#    define pthread_condattr_default  NULL
+#endif
+
+#ifndef PTHREAD_CREATE
+/* You are not supposed to pass NULL as the 2nd arg of PTHREAD_CREATE(). */
+#  define PTHREAD_CREATE(t,a,s,d) pthread_create(t,&(a),s,d)
+#endif
+
+#ifndef PTHREAD_ATTR_SETDETACHSTATE
+#  define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_attr_setdetachstate(a,s)
+#endif
+
+#ifndef PTHREAD_CREATE_JOINABLE
+#  ifdef OLD_PTHREAD_CREATE_JOINABLE
+#    define PTHREAD_CREATE_JOINABLE OLD_PTHREAD_CREATE_JOINABLE
+#  else
+#    define PTHREAD_CREATE_JOINABLE 0 /* Panic?  No, guess. */
+#  endif
+#endif
+
+#ifdef I_MACH_CTHREADS
+
+/* cthreads interface */
+
+/* #include <mach/cthreads.h> is in perl.h #ifdef I_MACH_CTHREADS */
+
+#define MUTEX_INIT(m) \
+    STMT_START {						\
+	*m = mutex_alloc();					\
+	if (*m) {						\
+	    mutex_init(*m);					\
+	} else {						\
+	    Perl_croak_nocontext("panic: MUTEX_INIT");		\
+	}							\
+    } STMT_END
+
+#define MUTEX_LOCK(m)			mutex_lock(*m)
+#define MUTEX_UNLOCK(m)			mutex_unlock(*m)
+#define MUTEX_DESTROY(m) \
+    STMT_START {						\
+	mutex_free(*m);						\
+	*m = 0;							\
+    } STMT_END
+
+#define COND_INIT(c) \
+    STMT_START {						\
+	*c = condition_alloc();					\
+	if (*c) {						\
+	    condition_init(*c);					\
+	}							\
+	else {							\
+	    Perl_croak_nocontext("panic: COND_INIT");		\
+	}							\
+    } STMT_END
+
+#define COND_SIGNAL(c)		condition_signal(*c)
+#define COND_BROADCAST(c)	condition_broadcast(*c)
+#define COND_WAIT(c, m)		condition_wait(*c, *m)
+#define COND_DESTROY(c) \
+    STMT_START {						\
+	condition_free(*c);					\
+	*c = 0;							\
+    } STMT_END
+
+#define THREAD_CREATE(thr, f)	(thr->self = cthread_fork(f, thr), 0)
+#define THREAD_POST_CREATE(thr)
+
+#define THREAD_RET_TYPE		any_t
+#define THREAD_RET_CAST(x)	((any_t) x)
+
+#define DETACH(t)		cthread_detach(t->self)
+#define JOIN(t, avp)		(*(avp) = (AV *)cthread_join(t->self))
+
+#define PERL_SET_CONTEXT(t)	cthread_set_data(cthread_self(), t)
+#define PERL_GET_CONTEXT	cthread_data(cthread_self())
+
+#define INIT_THREADS		cthread_init()
+#define YIELD			cthread_yield()
+#define ALLOC_THREAD_KEY	NOOP
+#define FREE_THREAD_KEY		NOOP
+#define SET_THREAD_SELF(thr)	(thr->self = cthread_self())
+
+#endif /* I_MACH_CTHREADS */
 
 #ifndef YIELD
-#  define YIELD sched_yield()
+#  ifdef SCHED_YIELD
+#    define YIELD SCHED_YIELD
+#  else
+#    ifdef HAS_SCHED_YIELD
+#      define YIELD sched_yield()
+#    else
+#      ifdef HAS_PTHREAD_YIELD
+    /* pthread_yield(NULL) platforms are expected
+     * to have #defined YIELD for themselves. */
+#        define YIELD pthread_yield()
+#      endif
+#    endif
+#  endif
+#endif
+
+#ifdef __hpux
+#  define MUTEX_INIT_NEEDS_MUTEX_ZEROED
 #endif
 
 #ifndef MUTEX_INIT
-#define MUTEX_INIT(m)						\
+
+#  ifdef MUTEX_INIT_NEEDS_MUTEX_ZEROED
+    /* Temporary workaround, true bug is deeper. --jhi 1999-02-25 */
+#    define MUTEX_INIT(m) \
+    STMT_START {						\
+	Zero((m), 1, perl_mutex);                               \
+ 	if (pthread_mutex_init((m), pthread_mutexattr_default))	\
+	    Perl_croak_nocontext("panic: MUTEX_INIT");		\
+    } STMT_END
+#  else
+#    define MUTEX_INIT(m) \
     STMT_START {						\
 	if (pthread_mutex_init((m), pthread_mutexattr_default))	\
-	    croak("panic: MUTEX_INIT");				\
+	    Perl_croak_nocontext("panic: MUTEX_INIT");		\
     } STMT_END
-#define MUTEX_LOCK(m)				\
-    STMT_START {				\
-	if (pthread_mutex_lock((m)))		\
-	    croak("panic: MUTEX_LOCK");		\
+#  endif
+
+#  define MUTEX_LOCK(m) \
+    STMT_START {						\
+	if (pthread_mutex_lock((m)))				\
+	    Perl_croak_nocontext("panic: MUTEX_LOCK");		\
     } STMT_END
-#define MUTEX_UNLOCK(m)				\
-    STMT_START {				\
-	if (pthread_mutex_unlock((m)))		\
-	    croak("panic: MUTEX_UNLOCK");	\
+
+#  define MUTEX_UNLOCK(m) \
+    STMT_START {						\
+	if (pthread_mutex_unlock((m)))				\
+	    Perl_croak_nocontext("panic: MUTEX_UNLOCK");	\
     } STMT_END
-#define MUTEX_DESTROY(m)			\
-    STMT_START {				\
-	if (pthread_mutex_destroy((m)))		\
-	    croak("panic: MUTEX_DESTROY");	\
+
+#  define MUTEX_DESTROY(m) \
+    STMT_START {						\
+	if (pthread_mutex_destroy((m)))				\
+	    Perl_croak_nocontext("panic: MUTEX_DESTROY");	\
     } STMT_END
 #endif /* MUTEX_INIT */
 
 #ifndef COND_INIT
-#define COND_INIT(c)						\
+#  define COND_INIT(c) \
     STMT_START {						\
 	if (pthread_cond_init((c), pthread_condattr_default))	\
-	    croak("panic: COND_INIT");				\
+	    Perl_croak_nocontext("panic: COND_INIT");		\
     } STMT_END
-#define COND_SIGNAL(c)				\
-    STMT_START {				\
-	if (pthread_cond_signal((c)))		\
-	    croak("panic: COND_SIGNAL");	\
+
+#  define COND_SIGNAL(c) \
+    STMT_START {						\
+	if (pthread_cond_signal((c)))				\
+	    Perl_croak_nocontext("panic: COND_SIGNAL");		\
     } STMT_END
-#define COND_BROADCAST(c)			\
-    STMT_START {				\
-	if (pthread_cond_broadcast((c)))	\
-	    croak("panic: COND_BROADCAST");	\
+
+#  define COND_BROADCAST(c) \
+    STMT_START {						\
+	if (pthread_cond_broadcast((c)))			\
+	    Perl_croak_nocontext("panic: COND_BROADCAST");	\
     } STMT_END
-#define COND_WAIT(c, m)				\
-    STMT_START {				\
-	if (pthread_cond_wait((c), (m)))	\
-	    croak("panic: COND_WAIT");		\
+
+#  define COND_WAIT(c, m) \
+    STMT_START {						\
+	if (pthread_cond_wait((c), (m)))			\
+	    Perl_croak_nocontext("panic: COND_WAIT");		\
     } STMT_END
-#define COND_DESTROY(c)				\
-    STMT_START {				\
-	if (pthread_cond_destroy((c)))		\
-	    croak("panic: COND_DESTROY");	\
+
+#  define COND_DESTROY(c) \
+    STMT_START {						\
+	if (pthread_cond_destroy((c)))				\
+	    Perl_croak_nocontext("panic: COND_DESTROY");	\
     } STMT_END
 #endif /* COND_INIT */
 
 /* DETACH(t) must only be called while holding t->mutex */
 #ifndef DETACH
-#define DETACH(t)				\
-    STMT_START {				\
-	if (pthread_detach((t)->self)) {	\
-	    MUTEX_UNLOCK(&(t)->mutex);		\
-	    croak("panic: DETACH");		\
-	}					\
+#  define DETACH(t) \
+    STMT_START {						\
+	if (pthread_detach((t)->self)) {			\
+	    MUTEX_UNLOCK(&(t)->mutex);				\
+	    Perl_croak_nocontext("panic: DETACH");		\
+	}							\
     } STMT_END
 #endif /* DETACH */
 
 #ifndef JOIN
-#define JOIN(t, avp) 					\
-    STMT_START {					\
-	if (pthread_join((t)->self, (void**)(avp)))	\
-	    croak("panic: pthread_join");		\
+#  define JOIN(t, avp) \
+    STMT_START {						\
+	if (pthread_join((t)->self, (void**)(avp)))		\
+	    Perl_croak_nocontext("panic: pthread_join");	\
     } STMT_END
 #endif /* JOIN */
 
-#ifndef SET_THR
-#define SET_THR(t)					\
-    STMT_START {					\
-	if (pthread_setspecific(thr_key, (void *) (t)))	\
-	    croak("panic: pthread_setspecific");	\
-    } STMT_END
-#endif /* SET_THR */
-
-#ifndef THR
-#  ifdef OLD_PTHREADS_API
-struct thread *getTHR _((void));
-#    define THR getTHR()
-#  else
-#    define THR ((struct thread *) pthread_getspecific(thr_key))
-#  endif /* OLD_PTHREADS_API */
-#endif /* THR */
+#ifndef PERL_GET_CONTEXT
+#  define PERL_GET_CONTEXT	pthread_getspecific(PL_thr_key)
+#endif
 
-#ifndef dTHR
-#  define dTHR struct thread *thr = THR
-#endif /* dTHR */
+#ifndef PERL_SET_CONTEXT
+#  define PERL_SET_CONTEXT(t) \
+    STMT_START {						\
+	if (pthread_setspecific(PL_thr_key, (void *)(t)))	\
+	    Perl_croak_nocontext("panic: pthread_setspecific");	\
+    } STMT_END
+#endif /* PERL_SET_CONTEXT */
 
 #ifndef INIT_THREADS
 #  ifdef NEED_PTHREAD_INIT
 #    define INIT_THREADS pthread_init()
-#  else
-#    define INIT_THREADS NOOP
 #  endif
 #endif
 
+#ifndef ALLOC_THREAD_KEY
+#  define ALLOC_THREAD_KEY \
+    STMT_START {						\
+	if (pthread_key_create(&PL_thr_key, 0))	{		\
+	    PerlIO_printf(PerlIO_stderr(), "panic: pthread_key_create");	\
+	    exit(1);						\
+	}							\
+    } STMT_END
+#endif
+
+#ifndef FREE_THREAD_KEY
+#  define FREE_THREAD_KEY \
+    STMT_START {						\
+	pthread_key_delete(PL_thr_key);				\
+    } STMT_END
+#endif
+
 #ifndef THREAD_RET_TYPE
 #  define THREAD_RET_TYPE	void *
 #  define THREAD_RET_CAST(p)	((void *)(p))
 #endif /* THREAD_RET */
 
-struct thread {
-    /* The fields that used to be global */
-    /* Important ones in the first cache line (if alignment is done right) */
-    SV **	Tstack_sp;
-#ifdef OP_IN_REGISTER
-    OP *	Topsave;
-#else
-    OP *	Top;
-#endif
-    SV **	Tcurpad;
-    SV **	Tstack_base;
-
-    SV **	Tstack_max;
-
-    I32 *	Tscopestack;
-    I32		Tscopestack_ix;
-    I32		Tscopestack_max;
-
-    ANY *	Tsavestack;
-    I32		Tsavestack_ix;
-    I32		Tsavestack_max;
-
-    OP **	Tretstack;
-    I32		Tretstack_ix;
-    I32		Tretstack_max;
-
-    I32 *	Tmarkstack;
-    I32 *	Tmarkstack_ptr;
-    I32 *	Tmarkstack_max;
-
-    SV *	TSv;
-    XPV *	TXpv;
-    struct stat	Tstatbuf;
-    struct tms	Ttimesbuf;
-    
-    /* XXX What about regexp stuff? */
-
-    /* Now the fields that used to be "per interpreter" (even when global) */
-
-    /* Fields used by magic variables such as $@, $/ and so on */
-    bool	Ttainted;
-    PMOP *	Tcurpm;
-    SV *	Tnrs;
-    SV *	Trs;
-    GV *	Tlast_in_gv;
-    char *	Tofs;
-    STRLEN	Tofslen;
-    GV *	Tdefoutgv;
-    char *	Tchopset;
-    SV *	Tformtarget;
-    SV *	Tbodytarget;
-    SV *	Ttoptarget;
-
-    /* Stashes */
-    HV *	Tdefstash;
-    HV *	Tcurstash;
-
-    /* Stacks */
-    SV **	Ttmps_stack;
-    I32		Ttmps_ix;
-    I32		Ttmps_floor;
-    I32		Ttmps_max;
-
-    int		Tin_eval;
-    OP *	Trestartop;
-    int		Tdelaymagic;
-    bool	Tdirty;
-    U8		Tlocalizing;
-    COP *	Tcurcop;
-
-    CONTEXT *	Tcxstack;
-    I32		Tcxstack_ix;
-    I32		Tcxstack_max;
-
-    AV *	Tcurstack;
-    AV *	Tmainstack;
-    JMPENV *	Ttop_env;
-    I32		Trunlevel;
-
-    /* XXX Sort stuff, firstgv, secongv and so on? */
-
-    SV *	oursv;
-    HV *	cvcache;
-    perl_thread	self;			/* Underlying thread object */
-    U32		flags;
-    AV *	magicals;		/* Per-thread magicals */
-    AV *	specific;		/* Thread-specific user data */
-    SV *	errsv;			/* Backing SV for $@ */
-    HV *	errhv;			/* HV for what was %@ in pp_ctl.c */
-    perl_mutex	mutex;			/* For the fields others can change */
-    U32		tid;
-    struct thread *next, *prev;		/* Circular linked list of threads */
-
-#ifdef ADD_THREAD_INTERN
-    struct thread_intern i;		/* Platform-dependent internals */
-#endif
-    char	trailing_nul;		/* For the sake of thrsv and oursv */
-};
-
-typedef struct thread *Thread;
+#if defined(USE_THREADS)
+
+/* Accessor for per-thread SVs */
+#  define THREADSV(i) (thr->threadsvp[i])
+
+/*
+ * LOCK_SV_MUTEX and UNLOCK_SV_MUTEX are performance-critical. Here, we
+ * try only locking them if there may be more than one thread in existence.
+ * Systems with very fast mutexes (and/or slow conditionals) may wish to
+ * remove the "if (threadnum) ..." test.
+ * XXX do NOT use C<if (PL_threadnum) ...> -- it sets up race conditions!
+ */
+#  define LOCK_SV_MUTEX		MUTEX_LOCK(&PL_sv_mutex)
+#  define UNLOCK_SV_MUTEX	MUTEX_UNLOCK(&PL_sv_mutex)
+#  define LOCK_STRTAB_MUTEX	MUTEX_LOCK(&PL_strtab_mutex)
+#  define UNLOCK_STRTAB_MUTEX	MUTEX_UNLOCK(&PL_strtab_mutex)
+#  define LOCK_CRED_MUTEX	MUTEX_LOCK(&PL_cred_mutex)
+#  define UNLOCK_CRED_MUTEX	MUTEX_UNLOCK(&PL_cred_mutex)
+#  define LOCK_FDPID_MUTEX	MUTEX_LOCK(&PL_fdpid_mutex)
+#  define UNLOCK_FDPID_MUTEX	MUTEX_UNLOCK(&PL_fdpid_mutex)
+#  define LOCK_SV_LOCK_MUTEX	MUTEX_LOCK(&PL_sv_lock_mutex)
+#  define UNLOCK_SV_LOCK_MUTEX	MUTEX_UNLOCK(&PL_sv_lock_mutex)
 
 /* Values and macros for thr->flags */
 #define THRf_STATE_MASK	7
@@ -241,14 +301,14 @@ typedef struct thread *Thread;
 #define THRf_ZOMBIE	3
 #define THRf_DEAD	4
 
-#define THRf_DIE_FATAL	8
+#define THRf_DID_DIE	8
 
 /* ThrSTATE(t) and ThrSETSTATE(t) must only be called while holding t->mutex */
-#define ThrSTATE(t) ((t)->flags)
+#define ThrSTATE(t) ((t)->flags & THRf_STATE_MASK)
 #define ThrSETSTATE(t, s) STMT_START {		\
 	(t)->flags &= ~THRf_STATE_MASK;		\
 	(t)->flags |= (s);			\
-	DEBUG_L(PerlIO_printf(PerlIO_stderr(),	\
+	DEBUG_S(PerlIO_printf(Perl_debug_log,	\
 			      "thread %p set to state %d\n", (t), (s))); \
     } STMT_END
 
@@ -264,138 +324,98 @@ typedef struct condpair {
 #define MgCONDP(mg) (&((condpair_t *)(mg->mg_ptr))->cond)
 #define MgOWNER(mg) ((condpair_t *)(mg->mg_ptr))->owner
 
-#undef	stack_base
-#undef	stack_sp
-#undef	stack_max
-#undef	curstack
-#undef	mainstack
-#undef	markstack
-#undef	markstack_ptr
-#undef	markstack_max
-#undef	scopestack
-#undef	scopestack_ix
-#undef	scopestack_max
-#undef	savestack
-#undef	savestack_ix
-#undef	savestack_max
-#undef	retstack
-#undef	retstack_ix
-#undef	retstack_max
-#undef	curcop
-#undef	cxstack
-#undef	cxstack_ix
-#undef	cxstack_max
-#undef	defstash
-#undef	curstash
-#undef	tmps_stack
-#undef	tmps_floor
-#undef	tmps_ix
-#undef	tmps_max
-#undef	curpad
-#undef	Sv
-#undef	Xpv
-#undef	statbuf
-#undef	timesbuf
-#undef	tainted
-#undef	curpm
-#undef	nrs
-#undef	rs
-#undef	last_in_gv
-#undef	ofs
-#undef	ofslen
-#undef	defoutgv
-#undef	chopset
-#undef	formtarget
-#undef	bodytarget
-#undef	toptarget
-#undef	top_env
-#undef	runlevel
-#undef	in_eval
-#undef	restartop
-#undef	delaymagic
-#undef	dirty
-#undef	localizing
-
-#define stack_base	(thr->Tstack_base)
-#define stack_sp	(thr->Tstack_sp)
-#define stack_max	(thr->Tstack_max)
-#ifdef OP_IN_REGISTER
-#define opsave		(thr->Topsave)
-#else
-#undef	op
-#define op		(thr->Top)
-#endif
-#define	curcop		(thr->Tcurcop)
-#define	stack		(thr->Tstack)
-#define curstack	(thr->Tcurstack)
-#define	mainstack	(thr->Tmainstack)
-#define	markstack	(thr->Tmarkstack)
-#define	markstack_ptr	(thr->Tmarkstack_ptr)
-#define	markstack_max	(thr->Tmarkstack_max)
-#define	scopestack	(thr->Tscopestack)
-#define	scopestack_ix	(thr->Tscopestack_ix)
-#define	scopestack_max	(thr->Tscopestack_max)
-
-#define	savestack	(thr->Tsavestack)
-#define	savestack_ix	(thr->Tsavestack_ix)
-#define	savestack_max	(thr->Tsavestack_max)
-
-#define	retstack	(thr->Tretstack)
-#define	retstack_ix	(thr->Tretstack_ix)
-#define	retstack_max	(thr->Tretstack_max)
-
-#define	cxstack		(thr->Tcxstack)
-#define	cxstack_ix	(thr->Tcxstack_ix)
-#define	cxstack_max	(thr->Tcxstack_max)
-
-#define curpad		(thr->Tcurpad)
-#define Sv		(thr->TSv)
-#define Xpv		(thr->TXpv)
-#define statbuf		(thr->Tstatbuf)
-#define timesbuf	(thr->Ttimesbuf)
-#define	tainted		(thr->Ttainted)
-#define	tainted		(thr->Ttainted)
-#define	curpm		(thr->Tcurpm)
-#define	nrs		(thr->Tnrs)
-#define	rs		(thr->Trs)
-#define	last_in_gv	(thr->Tlast_in_gv)
-#define	ofs		(thr->Tofs)
-#define	ofslen		(thr->Tofslen)
-#define	defoutgv	(thr->Tdefoutgv)
-#define	chopset		(thr->Tchopset)
-#define	formtarget	(thr->Tformtarget)
-#define	bodytarget	(thr->Tbodytarget)
-#define	toptarget	(thr->Ttoptarget)
-#define defstash	(thr->Tdefstash)
-#define curstash	(thr->Tcurstash)
-
-#define tmps_stack	(thr->Ttmps_stack)
-#define tmps_ix		(thr->Ttmps_ix)
-#define tmps_floor	(thr->Ttmps_floor)
-#define tmps_max	(thr->Ttmps_max)
-
-#define in_eval		(thr->Tin_eval)
-#define restartop	(thr->Trestartop)
-#define delaymagic	(thr->Tdelaymagic)
-#define dirty		(thr->Tdirty)
-#define localizing	(thr->Tlocalizing)
-
-#define	top_env		(thr->Ttop_env)
-#define	runlevel	(thr->Trunlevel)
-
-#else
-/* USE_THREADS is not defined */
-#define MUTEX_LOCK(m)
-#define MUTEX_UNLOCK(m)
-#define MUTEX_INIT(m)
-#define MUTEX_DESTROY(m)
-#define COND_INIT(c)
-#define COND_SIGNAL(c)
-#define COND_BROADCAST(c)
-#define COND_WAIT(c, m)
-#define COND_DESTROY(c)
-
-#define THR
-/* Rats: if dTHR is just blank then the subsequent ";" throws an error */
-#define dTHR extern int errno
 #endif /* USE_THREADS */
+#endif /* USE_THREADS || USE_ITHREADS */
+
+#ifndef MUTEX_LOCK
+#  define MUTEX_LOCK(m)
+#endif
+
+#ifndef MUTEX_UNLOCK
+#  define MUTEX_UNLOCK(m)
+#endif
+
+#ifndef MUTEX_INIT
+#  define MUTEX_INIT(m)
+#endif
+
+#ifndef MUTEX_DESTROY
+#  define MUTEX_DESTROY(m)
+#endif
+
+#ifndef COND_INIT
+#  define COND_INIT(c)
+#endif
+
+#ifndef COND_SIGNAL
+#  define COND_SIGNAL(c)
+#endif
+
+#ifndef COND_BROADCAST
+#  define COND_BROADCAST(c)
+#endif
+
+#ifndef COND_WAIT
+#  define COND_WAIT(c, m)
+#endif
+
+#ifndef COND_DESTROY
+#  define COND_DESTROY(c)
+#endif
+
+#ifndef LOCK_SV_MUTEX
+#  define LOCK_SV_MUTEX
+#endif
+
+#ifndef UNLOCK_SV_MUTEX
+#  define UNLOCK_SV_MUTEX
+#endif
+
+#ifndef LOCK_STRTAB_MUTEX
+#  define LOCK_STRTAB_MUTEX
+#endif
+
+#ifndef UNLOCK_STRTAB_MUTEX
+#  define UNLOCK_STRTAB_MUTEX
+#endif
+
+#ifndef LOCK_CRED_MUTEX
+#  define LOCK_CRED_MUTEX
+#endif
+
+#ifndef UNLOCK_CRED_MUTEX
+#  define UNLOCK_CRED_MUTEX
+#endif
+
+#ifndef LOCK_FDPID_MUTEX
+#  define LOCK_FDPID_MUTEX
+#endif
+
+#ifndef UNLOCK_FDPID_MUTEX
+#  define UNLOCK_FDPID_MUTEX
+#endif
+
+#ifndef LOCK_SV_LOCK_MUTEX
+#  define LOCK_SV_LOCK_MUTEX
+#endif
+
+#ifndef UNLOCK_SV_LOCK_MUTEX
+#  define UNLOCK_SV_LOCK_MUTEX
+#endif
+
+/* THR, SET_THR, and dTHR are there for compatibility with old versions */
+#ifndef THR
+#  define THR		PERL_GET_THX
+#endif
+
+#ifndef SET_THR
+#  define SET_THR(t)	PERL_SET_THX(t)
+#endif
+
+#ifndef dTHR
+#  define dTHR dNOOP
+#endif
+
+#ifndef INIT_THREADS
+#  define INIT_THREADS NOOP
+#endif