Add hooks for converting TLV values to and from host byte order.

Signed-off-by: Richard Cochran <richardcochran@gmail.com>

makefile

@@ -24,7 +24,7 @@ CFLAGS	= -Wall $(INC) $(DEBUG) $(EXTRA_CFLAGS)
 LDLIBS	= -lm -lrt $(EXTRA_LDFLAGS)
 PRG	= ptp4l phc2sys hwstamp_ctl
 OBJ	= bmc.o clock.o config.o fsm.o ptp4l.o mave.o msg.o phc.o pi.o port.o \
- print.o raw.o servo.o sk.o tmtab.o transport.o udp.o udp6.o util.o
+ print.o raw.o servo.o sk.o tlv.o tmtab.o transport.o udp.o udp6.o util.o
 
 OBJECTS	= $(OBJ) phc2sys.o hwstamp_ctl.o
 SRC	= $(OBJECTS:.o=.c)

msg.c

@@ -25,6 +25,7 @@
 
 #include "msg.h"
 #include "print.h"
+#include "tlv.h"
 
 #define VERSION_MASK 0x0f
 #define VERSION      0x02
@@ -164,6 +165,7 @@ static int suffix_post_recv(uint8_t *ptr, int len)
 		}
 		len -= tlv->length;
 		ptr += tlv->length;
+		tlv_post_recv(tlv);
 	}
 	return cnt;
 }
@@ -178,6 +180,7 @@ static void suffix_pre_send(uint8_t *ptr, int cnt)
 
 	for (i = 0; i < cnt; i++) {
 		tlv = (struct TLV *) ptr;
+		tlv_pre_send(tlv);
 		ptr += sizeof(struct TLV) + tlv->length;
 		tlv->type = htons(tlv->type);
 		tlv->length = htons(tlv->length);

tlv.c

@@ -0,0 +1,27 @@
+/**
+ * @file tlv.c
+ * @note Copyright (C) 2012 Richard Cochran <richardcochran@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+#include "tlv.h"
+
+void tlv_post_recv(struct TLV *tlv)
+{
+}
+
+void tlv_pre_send(struct TLV *tlv)
+{
+}

tlv.h

@@ -0,0 +1,37 @@
+/**
+ * @file tlv.h
+ * @brief Implements helper routines for processing Type Length Value fields.
+ * @note Copyright (C) 2012 Richard Cochran <richardcochran@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+#ifndef HAVE_TLV_H
+#define HAVE_TLV_H
+
+#include "ddt.h"
+
+/**
+ * Converts recognized value sub-fields into host byte order.
+ * @param tlv Pointer to a Type Length Value field.
+ */
+void tlv_post_recv(struct TLV *tlv);
+
+/**
+ * Converts recognized value sub-fields into network byte order.
+ * @param tlv Pointer to a Type Length Value field.
+ */
+void tlv_pre_send(struct TLV *tlv);
+
+#endif