From 82f15f091a8f16948b39d08a8e0144ad3ac2b701 Mon Sep 17 00:00:00 2001
From: Martin Ayotte <martinayotte@yahoo.ca>
Date: Tue, 11 Aug 2015 18:50:38 -0400
Subject: [PATCH] convert USBSerial and HardwareSerial to derived from Stream
 instead of Print

---
 .../cores/maple/libmaple/HardwareSerial.cpp   |  7 +++-
 STM32F4/cores/maple/libmaple/HardwareSerial.h | 11 ++++---
 STM32F4/cores/maple/libmaple/ring_buffer.h    | 19 +++++++++++
 STM32F4/cores/maple/libmaple/usart.h          | 12 +++++++
 STM32F4/cores/maple/usb_serial.cpp            | 32 +++++++++++++++++--
 STM32F4/cores/maple/usb_serial.h              | 12 ++++---
 6 files changed, 79 insertions(+), 14 deletions(-)

diff --git a/STM32F4/cores/maple/libmaple/HardwareSerial.cpp b/STM32F4/cores/maple/libmaple/HardwareSerial.cpp
index f6fdcbb..59ce71d 100644
--- a/STM32F4/cores/maple/libmaple/HardwareSerial.cpp
+++ b/STM32F4/cores/maple/libmaple/HardwareSerial.cpp
@@ -138,10 +138,15 @@ int HardwareSerial::read(void) {
 	}
 }
 
-uint32 HardwareSerial::available(void) {
+int HardwareSerial::available(void) {
     return usart_data_available(usart_device);
 }
 
+int HardwareSerial::peek(void)
+{
+    return usart_peek(usart_device);
+}
+    
 uint32 HardwareSerial::pending(void) {
     return usart_data_pending(usart_device);
 }
diff --git a/STM32F4/cores/maple/libmaple/HardwareSerial.h b/STM32F4/cores/maple/libmaple/HardwareSerial.h
index 9cad064..c09fe54 100644
--- a/STM32F4/cores/maple/libmaple/HardwareSerial.h
+++ b/STM32F4/cores/maple/libmaple/HardwareSerial.h
@@ -35,7 +35,7 @@
 #include "libmaple_types.h"
 #include "usart.h"
 
-#include "Print.h"
+#include "Stream.h"
 
 /*
  * IMPORTANT:
@@ -47,7 +47,7 @@
  * the documentation accordingly.
  */
 
-class HardwareSerial : public Print {
+class HardwareSerial : public Stream {
 public:
     HardwareSerial(usart_dev *usart_device,
                    uint8 tx_pin,
@@ -58,10 +58,11 @@ public:
     void end(void);
 
     /* I/O */
-    uint32 available(void);
+    virtual int available(void);
+    virtual int peek(void);
+    virtual void flush(void);
     uint32 pending(void);
-    int read(void);
-    void flush(void);
+    virtual int read(void);
     virtual size_t write(unsigned char);
     using Print::write;
 
diff --git a/STM32F4/cores/maple/libmaple/ring_buffer.h b/STM32F4/cores/maple/libmaple/ring_buffer.h
index c443bc3..b018522 100644
--- a/STM32F4/cores/maple/libmaple/ring_buffer.h
+++ b/STM32F4/cores/maple/libmaple/ring_buffer.h
@@ -126,6 +126,25 @@ static inline uint8 rb_remove(ring_buffer *rb) {
     return ch;
 }
 
+/*
+ * Roger Clark. 20141125, 
+ * added peek function.
+ * @brief Return the first item from a ring buffer, without removing it
+ * @param rb Buffer to remove from, must contain at least one element.
+ */
+static inline int rb_peek(ring_buffer *rb) 
+{  
+    if (rb->head == rb->tail)
+    {
+        return -1;
+    }
+    else
+    {
+	return rb->buf[rb->head];
+    }
+}
+
+
 /**
  * @brief Attempt to remove the first item from a ring buffer.
  *
diff --git a/STM32F4/cores/maple/libmaple/usart.h b/STM32F4/cores/maple/libmaple/usart.h
index a3dfc31..3f7c885 100644
--- a/STM32F4/cores/maple/libmaple/usart.h
+++ b/STM32F4/cores/maple/libmaple/usart.h
@@ -323,6 +323,18 @@ static inline uint8 usart_getc(usart_dev *dev) {
     return rb_remove(&dev->rbRX);
 }
 
+/*
+ * Roger Clark. 20141125,
+ * added peek function.
+ * @param dev Serial port to read from
+ * @return byte read
+ */
+static inline int usart_peek(usart_dev *dev)
+{
+    return rb_peek(&dev->rbRX);
+}
+
+
 /**
  * @brief Return the amount of data available in a serial port's RX buffer.
  * @param dev Serial port to check
diff --git a/STM32F4/cores/maple/usb_serial.cpp b/STM32F4/cores/maple/usb_serial.cpp
index 71d3b37..d606855 100644
--- a/STM32F4/cores/maple/usb_serial.cpp
+++ b/STM32F4/cores/maple/usb_serial.cpp
@@ -78,11 +78,11 @@ size_t USBSerial::write(const void *buf, uint32 len) {
     return txed;
 }
 
-uint32 USBSerial::available(void) {
+int USBSerial::available(void) {
     return usbBytesAvailable();
 }
 
-uint32 USBSerial::read(void *buf, uint32 len) {
+int USBSerial::read(void *buf, uint32 len) {
     if (!buf) {
         return 0;
     }
@@ -96,12 +96,38 @@ uint32 USBSerial::read(void *buf, uint32 len) {
 }
 
 /* Blocks forever until 1 byte is received */
-uint8 USBSerial::read(void) {
+int USBSerial::read(void) {
     uint8 buf[1];
     this->read(buf, 1);
     return buf[0];
 }
 
+int USBSerial::peek(void)
+{
+    // ThingToDo : Don't do any thing yet, since F4 doesn't have usb_cdcacm_peek() yet.
+    /*
+    uint8 b;
+    if (usb_cdcacm_peek(&b, 1)==1)
+    {
+	return b;
+    }
+    else */
+    {
+	return -1;
+    }
+}
+
+void USBSerial::flush(void)
+{
+    /*Roger Clark. Rather slow method. Need to improve this */
+    uint8 b;
+    while(usbBytesAvailable())
+    {
+	this->read(&b, 1);
+    }
+    return;
+}
+
 uint8 USBSerial::pending(void) {
     return usbGetPending();
 }
diff --git a/STM32F4/cores/maple/usb_serial.h b/STM32F4/cores/maple/usb_serial.h
index 44bd1e8..a551e9d 100644
--- a/STM32F4/cores/maple/usb_serial.h
+++ b/STM32F4/cores/maple/usb_serial.h
@@ -31,12 +31,12 @@
 #ifndef _USB_SERIAL_H_
 #define _USB_SERIAL_H_
 
-#include "Print.h"
+#include "Stream.h"
 
 /**
  * @brief Virtual serial terminal.
  */
-class USBSerial : public Print {
+class USBSerial : public Stream {
 public:
     USBSerial(void);
 
@@ -44,10 +44,12 @@ public:
     void begin(int);
     void end(void);
 
-    uint32 available(void);
+    virtual int available(void);
+    virtual int peek(void);
+    virtual void flush(void);
 
-    uint32 read(void *buf, uint32 len);
-    uint8  read(void);
+    virtual int read(void *buf, uint32 len);
+    virtual int read(void);
 
     size_t write(uint8);
     size_t write(const char *str);