1 files changed, 81 insertions, 0 deletions
diff --git a/sys/i4b/layer1/i4b_l1lib.c b/sys/i4b/layer1/i4b_l1lib.c
new file mode 100644
index 0000000..e4b0cd8
--- /dev/null
+++ b/sys/i4b/layer1/i4b_l1lib.c
@@ -0,0 +1,81 @@
+/*
+ * Copyright (c) 2000 Hellmuth Michaelis. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *---------------------------------------------------------------------------
+ *
+ *	i4b_l1lib.c - general useful L1 procedures
+ *	------------------------------------------
+ *
+ *	$Id: i4b_l1lib.c,v 1.3 2000/05/29 15:41:41 hm Exp $
+ *
+ * $FreeBSD$
+ *
+ *      last edit-date: [Mon May 29 15:24:21 2000]
+ *
+ *---------------------------------------------------------------------------*/
+
+#include <sys/param.h>
+#include <sys/kernel.h>
+#include <sys/systm.h>
+#include <sys/mbuf.h>
+#include <sys/socket.h>
+
+#include <net/if.h>
+
+#include <machine/i4b_debug.h>
+#include <machine/i4b_ioctl.h>
+#include <machine/i4b_trace.h>
+
+#include <i4b/layer1/i4b_l1.h>
+
+#define TEL_IDLE_MIN (BCH_MAX_DATALEN/2)
+
+/*---------------------------------------------------------------------------*
+ *	telephony silence detection
+ *---------------------------------------------------------------------------*/
+int
+i4b_l1_bchan_tel_silence(unsigned char *data, int len)
+{
+	register int i = 0;
+	register int j = 0;
+
+	/* count idle bytes */
+	
+	for(;i < len; i++)
+	{
+		if((*data >= 0xaa) && (*data <= 0xac))
+			j++;
+		data++;
+	}
+
+#ifdef NOTDEF
+	printf("i4b_l1_bchan_tel_silence: got %d silence bytes in frame\n", j);
+#endif
+	
+	if(j < (TEL_IDLE_MIN))
+		return(0);
+	else
+		return(1);
+
+}