From 7d00c19e810a98962dbf46f008c9d0c71eb6fb02 Mon Sep 17 00:00:00 2001
From: Matthias Ringwald <matthias@ringwald.ch>
Date: Wed, 27 Jan 2016 15:36:32 +0100
Subject: [PATCH 1/3] arduino: add C++ protection

---
 platforms/arduino/BTstack.h | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/platforms/arduino/BTstack.h b/platforms/arduino/BTstack.h
index ccb398afa..40d741592 100644
--- a/platforms/arduino/BTstack.h
+++ b/platforms/arduino/BTstack.h
@@ -1,7 +1,12 @@
 /**
  * Arduino Wrapper for BTstack
  */
-#pragma once
+#ifndef __ARDUINO_BTSTACK_H
+#define __ARDUINO_BTSTACK_H
+
+#if defined __cplusplus
+extern "C" {
+#endif
 
 #include "att.h"
 #include <btstack/utils.h> 
@@ -187,4 +192,10 @@ public:
  	uint16_t addGATTCharacteristicDynamic(UUID * uuid, uint16_t flags, uint16_t characteristic_id);
 };
 
- extern BTstackManager BTstack;
\ No newline at end of file
+extern BTstackManager BTstack;
+
+#if defined __cplusplus
+}
+#endif
+
+#endif // __ARDUINO_BTSTACK_H
\ No newline at end of file

From 83e7cdd948f2a1a6e3c1630bfa189f2ebf07b275 Mon Sep 17 00:00:00 2001
From: Matthias Ringwald <matthias@ringwald.ch>
Date: Thu, 28 Jan 2016 14:54:03 +0100
Subject: [PATCH 2/3] l2cap: add l2cap_can_send_prepared_packet_now

---
 src/l2cap.c | 6 ++++++
 src/l2cap.h | 5 ++++-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/l2cap.c b/src/l2cap.c
index bc9f797ad..574d01221 100644
--- a/src/l2cap.c
+++ b/src/l2cap.c
@@ -240,6 +240,12 @@ int  l2cap_can_send_packet_now(uint16_t local_cid){
     return hci_can_send_acl_packet_now(channel->handle);
 }
 
+int  l2cap_can_send_prepared_packet_now(uint16_t local_cid){
+    l2cap_channel_t *channel = l2cap_get_channel_for_local_cid(local_cid);
+    if (!channel) return 0;
+    return hci_can_send_prepared_acl_packet_now(channel->handle);
+}
+
 // @deprecated
 int l2cap_can_send_connectionless_packet_now(void){
     // TODO provide real handle
diff --git a/src/l2cap.h b/src/l2cap.h
index 694afba00..a401d1421 100644
--- a/src/l2cap.h
+++ b/src/l2cap.h
@@ -201,6 +201,7 @@ typedef struct l2cap_signaling_response {
 } l2cap_signaling_response_t;
     
 
+
 int  l2cap_can_send_fixed_channel_packet_now(uint16_t handle);
 
 // @deprecated use l2cap_can_send_fixed_channel_packet_now instead
@@ -261,7 +262,9 @@ void l2cap_decline_connection_internal(uint16_t local_cid, uint8_t reason);
 /** 
  * @brief Non-blocking UART write
  */
-int  l2cap_can_send_packet_now(uint16_t local_cid);    
+int  l2cap_can_send_packet_now(uint16_t local_cid); 
+int  l2cap_can_send_prepared_packet_now(uint16_t local_cid);
+ 
 int  l2cap_reserve_packet_buffer(void);
 void l2cap_release_packet_buffer(void);
 

From 92feaef78193405c2e2beed06b260e832cb5b4db Mon Sep 17 00:00:00 2001
From: Matthias Ringwald <matthias@ringwald.ch>
Date: Thu, 28 Jan 2016 14:54:43 +0100
Subject: [PATCH 3/3] rfcomm: release outgoing packet buffer in case of error
 in l2cap_send_prepared

---
 src/rfcomm.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/src/rfcomm.c b/src/rfcomm.c
index d59666bc0..f4ddf2e09 100644
--- a/src/rfcomm.c
+++ b/src/rfcomm.c
@@ -2029,6 +2029,10 @@ int rfcomm_send_prepared(uint16_t rfcomm_cid, uint16_t len){
 
     int err = rfcomm_assert_send_valid(channel, len);
     if (err) return err;
+    if (l2cap_can_send_prepared_packet_now(channel->multiplexer->l2cap_cid)){
+        log_error("rfcomm_send_prepared: l2cap cannot send now");
+        return BTSTACK_ACL_BUFFERS_FULL;
+    }
 
     // send might cause l2cap to emit new credits, update counters first
     channel->credits_outgoing--;
@@ -2037,12 +2041,11 @@ int rfcomm_send_prepared(uint16_t rfcomm_cid, uint16_t len){
     
     if (result != 0) {
         channel->credits_outgoing++;
-        log_info("rfcomm_send_internal: error %d", result);
+        log_error("rfcomm_send_prepared: error %d", result);
         return result;
     }
     
     rfcomm_hand_out_credits();
-    
     return result;
 }
 
@@ -2055,11 +2058,19 @@ int rfcomm_send_internal(uint16_t rfcomm_cid, uint8_t *data, uint16_t len){
 
     int err = rfcomm_assert_send_valid(channel, len);
     if (err) return err;
+    if (l2cap_can_send_packet_now(channel->multiplexer->l2cap_cid)){
+        log_error("rfcomm_send_internal: l2cap cannot send now");
+        return BTSTACK_ACL_BUFFERS_FULL;
+    }
 
     rfcomm_reserve_packet_buffer();
     uint8_t * rfcomm_payload = rfcomm_get_outgoing_buffer();
     memcpy(rfcomm_payload, data, len);
-    return rfcomm_send_prepared(rfcomm_cid, len);    
+    err = rfcomm_send_prepared(rfcomm_cid, len);    
+    if (err){
+        rfcomm_release_packet_buffer();
+    }
+    return err;
 }
 
 // Sends Local Lnie Status, see LINE_STATUS_..