Rewrite to remove dependence on rendezvous and its bizarre

data structures.  Makes it easier to use pthreads too.
Still need to add code for non-pthreads systems.

Just a checkpoint to switch work to another machine.

3 files changed, 43 insertions, 9 deletions

diff --git a/include/libc.h b/include/libc.h
index 93a9104a..1db39606 100644
--- a/include/libc.h
+++ b/include/libc.h
@@ -425,22 +425,49 @@ extern	void	needstack(int);
 /*
  *  synchronization
  */
-typedef
-struct Lock {
-	int	val;
-} Lock;
-
-extern int	_tas(int*);
+typedef struct Lock Lock;
+struct Lock
+{
+#ifdef PLAN9_PTHREADS
+	int init;
+	pthread_mutex_t mutex;
+#else
+	int val;
+#endif
+};
 
 extern	void	lock(Lock*);
 extern	void	unlock(Lock*);
 extern	int	canlock(Lock*);
 
+/*
+ * Used to implement process sleep and wakeup,
+ * either in terms of pthreads or our own primitives.
+ * This will be more portable than writing our own
+ * per-system implementations, and on some systems
+ * non-pthreads threading implementations break libc
+ * (cough, Linux, cough).
+ */
+typedef struct _Procrend _Procrend;
+struct _Procrend
+{
+	int asleep;
+	Lock *l;
+	void *arg;
+#ifdef PLAN9_PTHREADS
+	pthread_cond_t cond;
+#endif
+};
+
+extern	void	_procsleep(_Procrend*);
+extern	void	_procwakeup(_Procrend*);
+
 typedef struct QLp QLp;
 struct QLp
 {
-	int	inuse;
+	Lock	inuse;
 	QLp	*next;
+	_Procrend rend;
 	char	state;
 };
 
@@ -456,7 +483,7 @@ struct QLock
 extern	void	qlock(QLock*);
 extern	void	qunlock(QLock*);
 extern	int	canqlock(QLock*);
-extern	void	_qlockinit(ulong (*)(ulong, ulong));	/* called only by the thread library */
+extern	void	_qlockinit(void(*)(_Procrend*), void(*)(_Procrend*));	/* called only by the thread library */
 
 typedef
 struct RWLock
diff --git a/include/thread.h b/include/thread.h
index ce2d73bb..f2a12599 100644
--- a/include/thread.h
+++ b/include/thread.h
@@ -55,7 +55,7 @@ struct Alt {
 	/* the next variables are used internally to alt
 	 * they need not be initialized
 	 */
-	Channel	**tag;	/* pointer to rendez-vous tag */
+	struct Thread	*thread;	/* thread waiting on this alt */
 	int		entryno;	/* entry number */
 };
 
diff --git a/include/u.h b/include/u.h
index a7f97fc6..0cd8e397 100644
--- a/include/u.h
+++ b/include/u.h
@@ -41,6 +41,8 @@ typedef long p9jmp_buf[sizeof(sigjmp_buf)/sizeof(long)];
 #		undef _NEEDUSHORT
 #		undef _NEEDUINT
 #		undef _NEEDULONG
+#	include <pthread.h>
+#	define PLAN9_PTHREADS
 #	endif
 #endif
 #if defined(__sun__)
@@ -48,6 +50,8 @@ typedef long p9jmp_buf[sizeof(sigjmp_buf)/sizeof(long)];
 #	undef _NEEDUSHORT
 #	undef _NEEDUINT
 #	undef _NEEDULONG
+#	include <pthread.h>
+#	define PLAN9_PTHREADS
 #endif
 #if defined(__FreeBSD__)
 #	include <sys/types.h>
@@ -61,8 +65,11 @@ typedef long p9jmp_buf[sizeof(sigjmp_buf)/sizeof(long)];
 #	undef _NEEDUSHORT
 #	undef _NEEDUINT
 #	define _NEEDLL 1
+#	include <pthread.h>
+#	define PLAN9_PTHREADS
 #endif
 
+
 typedef signed char schar;
 typedef unsigned int u32int;
 typedef int s32int;