From aa294b27108f0b06f70469c2002eba16f746da0e Mon Sep 17 00:00:00 2001
From: XANTRONIX Development <dev@xantronix.com>
Date: Sat, 18 Jul 2015 02:22:25 -0500
Subject: [PATCH] =?UTF-8?q?Refactors=20with=20the=20lightest=20touch=20?=
 =?UTF-8?q?=F0=9F=92=85?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/ax25.c | 69 ++++++++++++++++++++++++++++++++++--------------------
 1 file changed, 44 insertions(+), 25 deletions(-)

diff --git a/src/ax25.c b/src/ax25.c
index 585de76..3d75a64 100644
--- a/src/ax25.c
+++ b/src/ax25.c
@@ -3,7 +3,7 @@
 
 #include <patty/ax25.h>
 
-static ssize_t frame_decode_address(patty_ax25_address *address, void *data, off_t offset) {
+static ssize_t frame_decode_station(patty_ax25_address *address, void *data, off_t offset) {
     int i, space = 0;
     uint8_t ssid = ((uint8_t *)data + offset)[6];
 
@@ -70,7 +70,7 @@ static ssize_t frame_decode_hops(patty_ax25_frame *frame, void *data, off_t star
      * frame.
      */
     for (i=0; i<PATTY_AX25_MAX_HOPS; i++) {
-        if ((decoded = frame_decode_address(&frame->repeaters[i], data, offset)) < 0) {
+        if ((decoded = frame_decode_station(&frame->repeaters[i], data, offset)) < 0) {
             goto error;
         } else {
             offset += decoded;
@@ -101,6 +101,44 @@ error:
     return -1;
 }
 
+static ssize_t frame_decode_address(patty_ax25_frame *frame, void *data, off_t start) {
+      off_t offset = start;
+    ssize_t decoded;
+
+    if ((decoded = frame_decode_station(&frame->dest, data, offset)) < 0) {
+        goto error;
+    } else {
+        offset += decoded;
+    }
+
+    /*
+     * It would be considered erroneous if the destination address did have the
+     * extension bit set to 1.
+     */
+    if ((decoded = frame_decode_station(&frame->src, data, offset)) < 0) {
+        goto error;
+    } else {
+        offset += decoded;
+    }
+
+    /*
+     * If the source address is not the final address in the frame, begin
+     * decoding repeater addresses.
+     */
+    if (!frame->src.last) {
+        if ((decoded = frame_decode_hops(frame, data, offset)) < 0) {
+            goto error;
+        } else {
+            offset += decoded;
+        }
+    }
+
+    return offset - start;
+
+error:
+    return -1;
+}
+
 static ssize_t frame_decode_payload(patty_ax25_frame *frame, void *data, off_t offset) {
     uint8_t control = ((uint8_t *)data + offset)[0];
      size_t decoded = 0;
@@ -160,34 +198,15 @@ int patty_ax25_frame_decode(patty_ax25_frame *frame, void *data, size_t size) {
 
     frame->size = size;
 
-    if ((decoded = frame_decode_address(&frame->dest, data, offset)) < 0) {
+    /*
+     * First, decode the variable-length Address field.
+     */
+    if ((decoded = frame_decode_address(frame, data, offset)) < 0) {
         goto error_decode;
     } else {
         offset += decoded;
     }
 
-    /*
-     * It would be considered erroneous if the destination address did have the
-     * extension bit set to 1.
-     */
-    if ((decoded = frame_decode_address(&frame->src, data, offset)) < 0) {
-        goto error_decode;
-    } else {
-        offset += decoded;
-    }
-
-    /*
-     * If the source address is not the final address in the frame, begin
-     * decoding repeater addresses.
-     */
-    if (!frame->src.last) {
-        if ((decoded = frame_decode_hops(frame, data, offset)) < 0) {
-            goto error_decode;
-        } else {
-            offset += decoded;
-        }
-    }
-
     /*
      * Now, decode the remaining Control Field, optional Protocol Identifier
      * field, and payload that may follow.