Revision 2:7e8a450a9101, committed 2013-05-24

Comitter:

sam_grove

Date:

Fri May 24 22:00:26 2013 +0000

Parent:

1:57a11fb5d529

Child:

3:6b76fcf27545

Commit message:

Override virtual member write. Better management of prime to avoid contentious writes under heavy traffic. updated puts to add \n per stdlib puts definition

Changed in this revision

--- a/BufferedSerial.cpp	Thu May 23 23:47:04 2013 +0000
+++ b/BufferedSerial.cpp	Fri May 24 22:00:26 2013 +0000
@@ -66,15 +66,16 @@
 
 int BufferedSerial::puts(const char *s)
 {
-    const char *size = s;
+    const char* ptr = s;
     
-    while(*(s) != 0)
+    while(*(ptr) != 0)
     {
-        _txbuf = *(s++);
+        _txbuf = *(ptr++);
     }
+    _txbuf = '\n';  // done per puts definition
     BufferedSerial::prime();
     
-    return s - size;
+    return (ptr - s) + 1;
 }
 
 int BufferedSerial::printf(const char* format, ...)
@@ -88,18 +89,33 @@
     // this may not hit the heap but should alert the user anyways
     if(r > sizeof(buf))
     {
-        ERROR("Buffer Overwrite Occured!\n");
+        ERROR("Buffer Overflow on the Stack Occured!\n");
     }
-    r = BufferedSerial::puts(buf);
+    r = BufferedSerial::write(buf, r);
     va_end(arg);
     
     return r;
 }
 
+ssize_t BufferedSerial::write(const void *s, size_t length)
+{
+    const char* ptr = (const char*)s;
+    const char* end = ptr + length;
+    
+    while (ptr != end)
+    {
+        _txbuf = *(ptr++);
+    }
+    BufferedSerial::prime();
+    
+    return ptr - (const char*)s;  
+}
+
+
 void BufferedSerial::rxIrq(void)
 {
     // read from the peripheral and see if things are available
-    while(serial_readable(&_serial))
+    if(serial_readable(&_serial))
     {
         _rxbuf = serial_getc(&_serial); // if so load them into a buffer
     }
@@ -110,7 +126,7 @@
 void BufferedSerial::txIrq(void)
 {
     // see if there is room in the hardware buffer and something is in the software buffer
-    while(serial_writable(&_serial) && _txbuf.available())
+    if(serial_writable(&_serial) && _txbuf.available())
     {
         serial_putc(&_serial, (int)_txbuf.get());
     }
@@ -120,12 +136,15 @@
 
 void BufferedSerial::prime(void)
 {
-    __disable_irq();    // make sure not to cause contention in the irq 
-    BufferedSerial::txIrq();    // prime the txirq to stoke transmit
-    __enable_irq();
+    // if already busy then the irq will pick this up
+    if(serial_writable(&_serial))
+    {
+        __disable_irq();    // make sure not to cause contention in the irq 
+        BufferedSerial::txIrq();    // prime the txirq - only write to hardware in one place
+        __enable_irq();
+    }
     
     return;
 }
 
 
-

--- a/BufferedSerial.h	Thu May 23 23:47:04 2013 +0000
+++ b/BufferedSerial.h	Fri May 24 22:00:26 2013 +0000
@@ -73,8 +73,8 @@
 class BufferedSerial : public Serial 
 {
 private:
-    Buffer <char> _rxbuf;
-    Buffer <char> _txbuf;
+    Buffer <char>   _rxbuf;
+    Buffer <char>   _txbuf;
  
     void rxIrq(void);
     void txIrq(void);
@@ -110,22 +110,28 @@
     
     /** Write a single byte to the BufferedSerial Port.
      *  @param c The byte to write to the Serial Port
-     *  @return The byte that was written to the Serial Port
+     *  @return The byte that was written to the Serial Port Buffer
      */
     virtual int putc(int c);
     
     /** Write a string to the BufferedSerial Port. Must be NULL terminated
      *  @param s The string to write to the Serial Port
-     *  @return The number of bytes written to the Serial Port
+     *  @return The number of bytes written to the Serial Port Buffer
      */
     virtual int puts(const char *s);
     
     /** Write a formatted string to the BufferedSerial Port.
      *  @param format The string + format specifiers to write to the Serial Port
-     *  @return The number of bytes written to the Serial Port
+     *  @return The number of bytes written to the Serial Port Buffer
      */
     virtual int printf(const char* format, ...);
     
+    /** Write data to the Buffered Serial Port
+     *  @param s A pointer to data to send
+     *  @param length The amount of data being pointed to
+     *  @return The number of bytes written to the Serial Port Buffer
+     */
+    virtual ssize_t write(const void *s, std::size_t length);
 };
 
 #endif