ape: add internal _NSEC() function and make gettimeofday() use it

1 files changed, 43 insertions, 0 deletions

diff --git a/sys/src/ape/lib/ap/plan9/9nsec.c b/sys/src/ape/lib/ap/plan9/9nsec.c
new file mode 100644
index 000000000..87d2e8a68
--- /dev/null
+++ b/sys/src/ape/lib/ap/plan9/9nsec.c
@@ -0,0 +1,43 @@
+#include "sys9.h"
+
+typedef unsigned long long uvlong;
+typedef long long vlong;
+typedef unsigned char uchar;
+
+static uvlong order = 0x0001020304050607ULL;
+
+static void
+be2vlong(vlong *to, uchar *f)
+{
+	uchar *t, *o;
+	int i;
+
+	t = (uchar*)to;
+	o = (uchar*)ℴ
+	for(i = 0; i < 8; i++)
+		t[o[i]] = f[i];
+}
+
+long long
+_NSEC(void)
+{
+	uchar b[8];
+	vlong t;
+	int opened;
+	static int fd = -1;
+
+	opened = 0;
+	for(;;) {
+		if(fd < 0)
+			if(opened++ ||
+			    (fd = _OPEN("/dev/bintime", OREAD|OCEXEC)) < 0)
+				return 0;
+		if(_PREAD(fd, b, sizeof b, 0) == sizeof b)
+			break;		/* leave fd open for future use */
+		/* short read, perhaps try again */
+		_CLOSE(fd);
+		fd = -1;
+	}
+	be2vlong(&t, b);
+	return t;
+}