rewrite serbridge buffering

serial/serbridge.c

@@ -22,19 +22,6 @@ sint8  ICACHE_FLASH_ATTR espbuffsend(serbridgeConnData *conn, const char *data,
 
 // Connection pool
 serbridgeConnData connData[MAX_CONN];
-// Transmit buffers for the connection pool
-static char txbuffer[MAX_CONN][MAX_TXBUFFER];
-
-// Given a pointer to an espconn struct find the connection that correcponds to it
-static serbridgeConnData ICACHE_FLASH_ATTR *serbridgeFindConnData(void *arg) {
-	for (int i=0; i<MAX_CONN; i++) {
-		if (connData[i].conn == (struct espconn *)arg) {
-			return &connData[i];
-		}
-	}
-	//os_printf("FindConnData: Huh? Couldn't find connection for %p\n", arg);
-	return NULL; // not found, may be closed already...
-}
 
 // Send all data in conn->txbuffer
 // returns result from espconn_sent if data in buffer or ESPCONN_OK (0)
@@ -45,40 +32,67 @@ static sint8 ICACHE_FLASH_ATTR sendtxbuffer(serbridgeConnData *conn) {
     //os_printf("%d TX %d\n", system_get_time(), conn->txbufferlen);
     conn->readytosend = false;
     result = espconn_sent(conn->conn, (uint8_t*)conn->txbuffer, conn->txbufferlen);
-		conn->txbufferlen = 0;
     if (result != ESPCONN_OK) {
       os_printf("sendtxbuffer: espconn_sent error %d on conn %p\n", result, conn);
+      conn->txbufferlen = 0;
+    } else {
+      conn->sentbuffer = conn->txbuffer;
+      conn->txbuffer = NULL;
+      conn->txbufferlen = 0;
     }
   }
   return result;
 }
 
+static char *tx_full_msg = "espbuffsend: txbuffer full on conn %p\n";
+
 // espbuffsend adds data to the send buffer. If the previous send was completed it calls
 // sendtxbuffer and espconn_sent.
 // Returns ESPCONN_OK (0) for success, -128 if buffer is full or error from  espconn_sent
 // Use espbuffsend instead of espconn_sent as it solves the problem that espconn_sent must
 // only be called *after* receiving an espconn_sent_callback for the previous packet.
 sint8 ICACHE_FLASH_ATTR espbuffsend(serbridgeConnData *conn, const char *data, uint16 len) {
-	if (conn->txbufferlen + len > MAX_TXBUFFER) {
+  if (conn->txbufferlen >= MAX_TXBUFFER) {
-		os_printf("espbuffsend: txbuffer full on conn %p\n", conn);
+    os_printf(tx_full_msg, conn);
+    return -128;
+  }
+
+  // make sure we indeed have a buffer
+  if (conn->txbuffer == NULL) conn->txbuffer = os_zalloc(MAX_TXBUFFER);
+  if (conn->txbuffer == NULL) {
+    os_printf("espbuffsend: cannot alloc tx buffer\n");
     return -128;
   }
-	os_memcpy(conn->txbuffer + conn->txbufferlen, data, len);
+
+  // add to send buffer
+  uint16_t avail = conn->txbufferlen+len > MAX_TXBUFFER ? MAX_TXBUFFER-conn->txbufferlen : len;
+  os_memcpy(conn->txbuffer + conn->txbufferlen, data, avail);
   conn->txbufferlen += len;
-	if (conn->readytosend) {
+
-		return sendtxbuffer(conn);
+  // try to send
-	} else {
+  sint8 result = ESPCONN_OK;
-		//os_printf("%d QU %d\n", system_get_time(), conn->txbufferlen);
+  if (conn->readytosend) result = sendtxbuffer(conn);
+
+  if (avail < len) {
+    // some data didn't fit into the buffer
+    if (conn->txbufferlen == 0) {
+      // we sent the prior buffer, so try again
+      return espbuffsend(conn, data+avail, len-avail);
+    }
+    os_printf(tx_full_msg, conn);
+    return -128;
   }
-	return ESPCONN_OK;
+  return result;
 }
 
 //callback after the data are sent
 static void ICACHE_FLASH_ATTR serbridgeSentCb(void *arg) {
-	serbridgeConnData *conn = serbridgeFindConnData(arg);
+  serbridgeConnData *conn = ((struct espconn*)arg)->reverse;
   //os_printf("Sent callback on conn %p\n", conn);
   if (conn == NULL) return;
   //os_printf("%d ST\n", system_get_time());
+  if (conn->sentbuffer != NULL) os_free(conn->sentbuffer);
+  conn->sentbuffer = NULL;
   conn->readytosend = true;
   sendtxbuffer(conn); // send possible new data in txbuffer
 }
@@ -192,7 +206,7 @@ void ICACHE_FLASH_ATTR serbridgeReset() {
 
 // Receive callback
 static void ICACHE_FLASH_ATTR serbridgeRecvCb(void *arg, char *data, unsigned short len) {
-	serbridgeConnData *conn = serbridgeFindConnData(arg);
+  serbridgeConnData *conn = ((struct espconn*)arg)->reverse;
   //os_printf("Receive callback on conn %p\n", conn);
   if (conn == NULL) return;
 
@@ -245,35 +259,29 @@ static void ICACHE_FLASH_ATTR serbridgeRecvCb(void *arg, char *data, unsigned sh
   serledFlash(50); // short blink on serial LED
 }
 
-// Error callback (it's really poorly named, it's not a "connection reconnected" callback,
-// it's really a "connection broken, please reconnect" callback)
-static void ICACHE_FLASH_ATTR serbridgeReconCb(void *arg, sint8 err) {
-	serbridgeConnData *conn=serbridgeFindConnData(arg);
-	if (conn == NULL) return;
-	// Close the connection
-	espconn_disconnect(conn->conn);
-	conn->conn = NULL;
-}
-
 // Disconnection callback
 static void ICACHE_FLASH_ATTR serbridgeDisconCb(void *arg) {
-	// Iterate through all the connections and deallocate the ones that are in a state that
+  serbridgeConnData *conn = ((struct espconn*)arg)->reverse;
-	// indicates that they're closed
+  if (conn == NULL) return;
-	for (int i=0; i<MAX_CONN; i++) {
+  // Free buffers
-		if (connData[i].conn != NULL &&
+  if (conn->sentbuffer != NULL) os_free(conn->sentbuffer);
-		   (connData[i].conn->state == ESPCONN_NONE || connData[i].conn->state == ESPCONN_CLOSE))
+  conn->sentbuffer = NULL;
-		{
+  if (conn->txbuffer != NULL) os_free(conn->txbuffer);
-			if (connData[i].conn_mode == cmAVR) {
+  conn->txbuffer = NULL;
-				// send reset to arduino/ARM
+  conn->txbufferlen = 0;
-				if (mcu_reset_pin >= 0) {
+  // Send reset to attached uC if it was in programming mode
+  if (conn->conn_mode == cmAVR && mcu_reset_pin >= 0) {
     GPIO_OUTPUT_SET(mcu_reset_pin, 0);
     os_delay_us(100L);
     GPIO_OUTPUT_SET(mcu_reset_pin, 1);
   }
-			}
+  conn->conn = NULL;
-			connData[i].conn = NULL;
+}
-		}
+
-	}
+// Connection reset callback (note that there will be no DisconCb)
+static void ICACHE_FLASH_ATTR serbridgeResetCb(void *arg, sint8 err) {
+  os_printf("serbridge: connection reset err=%d\n", err);
+  serbridgeDisconCb(arg);
 }
 
 // New connection callback, use one of the connection descriptors, if we have one left.
@@ -290,15 +298,15 @@ static void ICACHE_FLASH_ATTR serbridgeConnectCb(void *arg) {
     return;
   }
 
-	connData[i].conn=conn;
+  os_memset(connData+i, 0, sizeof(struct serbridgeConnData));
-	connData[i].txbufferlen = 0;
+  connData[i].conn = conn;
+  conn->reverse = connData+i;
   connData[i].readytosend = true;
-	connData[i].telnet_state = 0;
   connData[i].conn_mode = cmInit;
 
   espconn_regist_recvcb(conn, serbridgeRecvCb);
-	espconn_regist_reconcb(conn, serbridgeReconCb);
   espconn_regist_disconcb(conn, serbridgeDisconCb);
+  espconn_regist_reconcb(conn, serbridgeResetCb);
   espconn_regist_sentcb(conn, serbridgeSentCb);
 
   espconn_set_opt(conn, ESPCONN_REUSEADDR|ESPCONN_NODELAY);
@@ -349,10 +357,8 @@ void ICACHE_FLASH_ATTR serbridgeInitPins() {
 void ICACHE_FLASH_ATTR serbridgeInit(int port) {
   serbridgeInitPins();
 
-	int i;
+  for (int i = 0; i < MAX_CONN; i++) {
-	for (i = 0; i < MAX_CONN; i++) {
     connData[i].conn = NULL;
-		connData[i].txbuffer = txbuffer[i];
   }
   serbridgeConn.type = ESPCONN_TCP;
   serbridgeConn.state = ESPCONN_NONE;

serial/serbridge.h

@@ -8,8 +8,8 @@
 #define MAX_CONN 4
 #define SER_BRIDGE_TIMEOUT 28799
 
-//Max send buffer len
+// Send buffer size
-#define MAX_TXBUFFER 1024
+#define MAX_TXBUFFER 2048
 
 typedef struct serbridgeConnData serbridgeConnData;
 
@@ -28,7 +28,8 @@ struct serbridgeConnData {
 	enum connModes conn_mode;     // connection mode
 	char           *txbuffer;     // buffer for the data to send
 	uint16         txbufferlen;   // length of data in txbuffer
-	bool           readytosend; // true, if txbuffer can send by espconn_sent
+  char           *sentbuffer;   // buffer sent, awaiting callback to get freed
+	bool           readytosend;   // true, if txbuffer can be sent by espconn_sent
   uint8_t        telnet_state;
 };