From d87d827d8881772903c1ebf470c06305dc6ad340 Mon Sep 17 00:00:00 2001
From: Oleg Hahm <oleg@hobbykeller.org>
Date: Sat, 23 Nov 2013 14:03:26 +0100
Subject: [PATCH] transceiver return signed values for sending

negative values indicate an error value
---
 cpu/native/include/nativenet.h        |  4 ++--
 cpu/native/net/interface.c            |  8 ++------
 drivers/at86rf231/at86rf231_tx.c      |  1 +
 drivers/cc110x_ng/cc110x-tx.c         |  4 ++--
 drivers/cc110x_ng/include/cc110x_ng.h |  2 +-
 sys/transceiver/transceiver.c         | 20 ++++++--------------
 6 files changed, 14 insertions(+), 25 deletions(-)

diff --git a/cpu/native/include/nativenet.h b/cpu/native/include/nativenet.h
index 25c75f6e4e..62e00bfcce 100644
--- a/cpu/native/include/nativenet.h
+++ b/cpu/native/include/nativenet.h
@@ -59,9 +59,9 @@ void nativenet_set_monitor(uint8_t mode);
  * Send a packet
  *
  * @param packet a radio packet
- * @return 1 on success, 0 otherwise
+ * @return -1 if the operation failed, 0 otherwise
  */
-uint8_t nativenet_send(radio_packet_t *packet);
+int8_t nativenet_send(radio_packet_t *packet);
 
 /**
  * Set transceiver address
diff --git a/cpu/native/net/interface.c b/cpu/native/net/interface.c
index a3af8a49e6..215f16b02f 100644
--- a/cpu/native/net/interface.c
+++ b/cpu/native/net/interface.c
@@ -107,16 +107,12 @@ radio_address_t nativenet_get_address()
     return _native_net_addr;
 }
 
-uint8_t nativenet_send(radio_packet_t *packet)
+int8_t nativenet_send(radio_packet_t *packet)
 {
     packet->src = _native_net_addr;
     DEBUG("nativenet_send:  Sending packet of length %"PRIu16" from %"PRIu16" to %"PRIu16"\n", packet->length, packet->src, packet->dst);
 
-    if (send_buf(packet) == -1) {
-        warnx("nativenet_send: error sending packet");
-        return 0;
-    }
-    return true;
+    return send_buf(packet);
 }
 
 void nativenet_switch_to_rx()
diff --git a/drivers/at86rf231/at86rf231_tx.c b/drivers/at86rf231/at86rf231_tx.c
index 1ca09e8f8e..1bb2231468 100644
--- a/drivers/at86rf231/at86rf231_tx.c
+++ b/drivers/at86rf231/at86rf231_tx.c
@@ -54,6 +54,7 @@ int16_t at86rf231_send(at86rf231_packet_t *packet)
 
     // transmit packet
     at86rf231_xmit(pkt, packet->length);
+    return packet->length;
 }
 
 static void at86rf231_xmit(uint8_t *data, uint8_t length)
diff --git a/drivers/cc110x_ng/cc110x-tx.c b/drivers/cc110x_ng/cc110x-tx.c
index 586654058c..6759db3069 100644
--- a/drivers/cc110x_ng/cc110x-tx.c
+++ b/drivers/cc110x_ng/cc110x-tx.c
@@ -28,7 +28,7 @@
 
 //#include <board.h>
 
-uint8_t cc110x_send(cc110x_packet_t *packet)
+int8_t cc110x_send(cc110x_packet_t *packet)
 {
     volatile uint32_t abort_count;
     uint8_t size;
@@ -95,6 +95,6 @@ uint8_t cc110x_send(cc110x_packet_t *packet)
     /* Go to mode after TX (CONST_RX -> RX, WOR -> WOR) */
     cc110x_switch_to_rx();
 
-    return true;
+    return size;
 }
 
diff --git a/drivers/cc110x_ng/include/cc110x_ng.h b/drivers/cc110x_ng/include/cc110x_ng.h
index c3ca907474..a45a6b9cce 100644
--- a/drivers/cc110x_ng/include/cc110x_ng.h
+++ b/drivers/cc110x_ng/include/cc110x_ng.h
@@ -116,7 +116,7 @@ void cc110x_init(int transceiver_pid);
 
 void cc110x_rx_handler(void);
 
-uint8_t cc110x_send(cc110x_packet_t *pkt);
+int8_t cc110x_send(cc110x_packet_t *pkt);
 
 uint8_t cc110x_get_buffer_pos(void);
 
diff --git a/sys/transceiver/transceiver.c b/sys/transceiver/transceiver.c
index 6c36de4715..1131710db7 100644
--- a/sys/transceiver/transceiver.c
+++ b/sys/transceiver/transceiver.c
@@ -116,7 +116,7 @@ static void receive_nativenet_packet(radio_packet_t *trans_p);
 #ifdef MODULE_AT86RF231
 void receive_at86rf231_packet(radio_packet_t *trans_p);
 #endif
-static uint8_t send_packet(transceiver_type_t t, void *pkt);
+static int8_t send_packet(transceiver_type_t t, void *pkt);
 static int16_t get_channel(transceiver_type_t t);
 static int16_t set_channel(transceiver_type_t t, void *channel);
 static int16_t get_address(transceiver_type_t t);
@@ -580,14 +580,11 @@ void receive_at86rf231_packet(radio_packet_t *trans_p) {
  * @param t     The transceiver device
  * @param pkt   Generic pointer to the packet
  *
- * @return 1 on success, 0 otherwise
+ * @return A negative value if operation failed, 0 or the number of bytes sent otherwise.
  */
-static uint8_t send_packet(transceiver_type_t t, void *pkt)
+static int8_t send_packet(transceiver_type_t t, void *pkt)
 {
-    uint8_t res = 0;
-#ifdef MODULE_CC110X
-    int snd_ret;
-#endif
+    int8_t res = -1;
     radio_packet_t p = *((radio_packet_t *)pkt);
 
 #ifdef MODULE_CC110X_NG
@@ -617,13 +614,8 @@ static uint8_t send_packet(transceiver_type_t t, void *pkt)
 #elif MODULE_CC110X
             memcpy(cc1100_pkt, p.data, p.length);
 
-            if ((snd_ret = cc1100_send_csmaca(p.dst, 4, 0, (char *) cc1100_pkt, p.length)) < 0) {
-                DEBUG("transceiver: snd_ret (%u) = %i\n", p.length, snd_ret);
-                res = 0;
-            }
-            else {
-                res = 1;
-            }
+            res = cc1100_send_csmaca(p.dst, 4, 0, (char *) cc1100_pkt, p.length);
+            DEBUG("transceiver: snd_ret (%u) = %i\n", p.length, snd_ret);
 #else
             puts("Unknown transceiver");
 #endif