Continue switching library over to pthreads when possible.

Tprimes works on Linux 2.6.  You can only have 128 procs
though.

1 files changed, 58 insertions, 1 deletions

diff --git a/src/lib9/rendez-Linux.c b/src/lib9/rendez-Linux.c
index 673818e0..6d479310 100644
--- a/src/lib9/rendez-Linux.c
+++ b/src/lib9/rendez-Linux.c
@@ -1,3 +1,60 @@
-/* Could use futex(2) here instead of signals? */
+/*
+ * On Linux 2.6 and later, we can use pthreads (in fact, we must),
+ * but on earlier Linux, pthreads are incompatible with using our
+ * own coroutines in libthread.  In order to make binaries that work
+ * on either system, we detect the pthread library in use and call
+ * the appropriate functions.
+ */
 
+#include <u.h>
+#include <signal.h>
+#include <pthread.h>
+#include <libc.h>
+
+#define _procsleep _procsleep_signal
+#define _procwakeup _procwakeup_signal
 #include "rendez-signal.c"
+
+#undef _procsleep
+#undef _procwakeup
+#define _procsleep _procsleep_pthread
+#define _procwakeup _procwakeup_pthread
+#include "rendez-pthread.c"
+
+#undef _procsleep
+#undef _procwakeup
+
+int
+_islinuxnptl(void)
+{
+	static char buf[100];
+	static int isnptl = -1;
+
+	if(isnptl == -1){
+		if(confstr(_CS_GNU_LIBPTHREAD_VERSION, buf, sizeof buf) > 0
+		&& strncmp(buf, "NPTL", 4) == 0)
+			isnptl = 1;
+		else
+			isnptl = 0;
+	}
+	return isnptl;
+}
+
+void
+_procsleep(_Procrend *r)
+{
+	if(_islinuxnptl())
+		return _procsleep_pthread(r);
+	else
+		return _procsleep_signal(r);
+}
+
+void
+_procwakeup(_Procrend *r)
+{
+	if(_islinuxnptl())
+		return _procwakeup_pthread(r);
+	else
+		return _procwakeup_signal(r);
+}
+