0.1.4 DEVNULL

libraries/DEVNULL/DEVNULL.cpp

@@ -0,0 +1,51 @@
+//
+//    FILE: DEVNULL.cpp
+//  AUTHOR: Rob Tillaart
+// VERSION: 0.1.4
+// PURPOSE: Arduino library for a /dev/null stream - useful for testing
+//     URL: https://github.com/RobTillaart/DEVNULL
+//
+// HISTORY:
+//  0.1.0   2020-06-23  initial version.
+//  0.1.1   2020-12-18  add Arduino-CI.
+//  0.1.2   2021-11-24  update build-CI, badges, etc.
+//                      added write(data, length) + _timeOut.
+//  0.1.3   2021-12-15  update library.json, license, minor edits
+//  0.1.4   2022-09-21  split up .h in .cpp and .h
+//                      add last() to check last byte written to.
+
+
+#include "DEVNULL.h"
+
+DEVNULL::DEVNULL()
+{
+  setTimeout(0);        //  no timeout.
+  _bottomLessPit = -1;  //  nothing in the pit
+}
+
+int  DEVNULL::available() { return 0; };
+int  DEVNULL::peek()      { return EOF; };
+int  DEVNULL::read()      { return EOF; };
+//  placeholder to keep CI happy
+void DEVNULL::flush()     { return; };
+
+size_t DEVNULL::write(const uint8_t data)
+{
+  _bottomLessPit = data;
+  return 1;
+}
+
+size_t DEVNULL::write( const uint8_t *buffer, size_t size)
+{
+  if (size > 0) _bottomLessPit = buffer[size - 1];
+  return size;
+}
+
+int DEVNULL::lastByte()
+{
+  return _bottomLessPit;
+}
+
+
+// -- END OF FILE --
+

libraries/DEVNULL/DEVNULL.h

@@ -2,47 +2,30 @@
 //
 //    FILE: DEVNULL.h
 //  AUTHOR: Rob Tillaart
-// VERSION: 0.1.3
+// VERSION: 0.1.4
 // PURPOSE: Arduino library for a /dev/null stream - useful for testing
 //     URL: https://github.com/RobTillaart/DEVNULL
-//
-// HISTORY:
-//  0.1.0   2020-06-23  initial version.
-//  0.1.1   2020-12-18  add Arduino-CI.
-//  0.1.2   2021-11-24  update build-CI, badges, etc.
-//                      added write(data, length) + _timeOut.
-//  0.1.3   2021-12-15  update library.json, license, minor edits
 
 
 #include "Arduino.h"
 
-#define DEVNULL_LIB_VERSION     (F("0.1.3"))
+#define DEVNULL_LIB_VERSION     (F("0.1.4"))
 
 
 class DEVNULL : public Stream
 {
 public:
-  DEVNULL()
-  {
-    setTimeout(0);     // no timeout.
-  };
+  DEVNULL();
 
-  int    available() { return 0; };
-  int    peek()      { return EOF; };
-  int    read()      { return EOF; };
-  void   flush()     { return; };  // placeholder to keep CI happy
+  int    available();
+  int    peek();
+  int    read();
+  void   flush();  //  placeholder to keep CI happy
 
-  size_t write(const uint8_t data)
-  {
-    _bottomLessPit = data;
-    return 1;
-  };
-  size_t write( const uint8_t *buffer, size_t size) 
-  {
-    if (size > 0) _bottomLessPit = buffer[size - 1];
-    return size;
-  };
+  size_t write(const uint8_t data);
+  size_t write( const uint8_t *buffer, size_t size);
 
+  int    lastByte();
 
 private:
   uint8_t  _bottomLessPit;

libraries/DEVNULL/README.md

@@ -30,12 +30,18 @@ with only a return 0; (or at least **print(Type)** as the **println(T)** would o
 call once extra for the "\n".
 
 
-#### Version 0.1.2
+## Versions
 
-- sets the timeout for reading to 0. No need to wait longer with DEVNULl.
+#### 0.1.2
+
+- sets the timeout for reading to 0. No need to wait longer with DEVNULL.
   this improves the **find(...)** calls substantially.
 - added **size_t write( const uint8_t \*buffer, size_t size)** for faster string processing.
 
+#### 0.1.4
+
+- add **lastByte()** to check last byte written.
+- split of .cpp
 
 ## Interface
 
@@ -45,10 +51,10 @@ call once extra for the "\n".
 - **int read()** always return EOF.
 - **void flush()** does nothing but keeps some compilers happy.
 - **size_t write(const uint8_t data)** implements print interface. returns 1.
-
-0.1.2 added to improve performance a few percent (UNO).
-
-- **size_t write( const uint8_t \*buffer, size_t size)** implements print interface. returns size.
+- **size_t write( const uint8_t \*buffer, size_t size)** implements print interface.
+Returns size.
+- **int lastByte()** returns last byte written (debug and test purpose).
+Returns -1 if no byte has been written yet.
 
 
 ## Operation
@@ -60,11 +66,22 @@ See examples.
 
 ## Future
 
-- add optional delay to mimic pause / tune behaviour for simulating other devices
-  microseconds - milliseconds?
-  delay per byte or per call to write? (esp long arrays might need other performance
-  feels out of scope for /dev/null
+#### Could
+
 - add byte counter (uint32_t)
-- add lastWrittenByte() - look at the last byte written to the bottomless pit.
+- investigate if DEVNULL can be used to harvest entropy?
+  - sum xor of all data + timestamp?
+  - enable / disable flag (complex)
+  - => /dev/entropy class?
+- **flush()** could reset bottomLessPit to -1?
 
 
+#### Wont
+
+- add delay to mimic pause / tune behaviour for simulating devices
+  - microseconds
+  - delay per byte, esp long arrays might need other performance
+  - out of scope for /dev/null => separate class?
+- implement Print class to increase performance?
+  - derived class?
+

libraries/DEVNULL/examples/DEVNULL_performance/DEVNULL_performance.ino

@@ -1,10 +1,7 @@
 //
 //    FILE: DEVNULL_performance.ino
-//  AUTHOR: Rob Tillaart
-// VERSION: 0.1.0
+//  AUTHOR: Rob Tillaart0
 // PURPOSE: demo
-//    DATE: 2021-11-24
-//    (c) : MIT
 //
 
 
@@ -80,10 +77,21 @@ void setup()
 
 
   start = micros();
-  bool b = dn.find("hello");
+  bool b = dn.find((char*)"hello");
   stop = micros();
   Serial.print("find: \t");
   Serial.println(stop - start);
+  Serial.print("find: \t");
+  Serial.println(b);
+  delay(10);
+
+  start = micros();
+  int v = dn.lastByte();
+  stop = micros();
+  Serial.print("last: \t");
+  Serial.println(stop - start);
+  Serial.print("last: \t");
+  Serial.println(v);
   delay(10);
 
 
@@ -97,4 +105,3 @@ void loop()
 
 
 // -- END OF FILE --
-

libraries/DEVNULL/examples/DEVNULL_performance/performance_0.1.4.txt

@@ -0,0 +1,20 @@
+// test run on IDE 1.8.13 UNO
+
+DEVNULL_performance.ino
+DEVNULL_LIB_VERSION: 0.1.4
+text1: 	20
+text2: 	4
+long: 	356
+float: 	596
+float: 	1092
+float: 	1604
+float: 	2120
+find: 	8
+find: 	0
+last: 	4
+last: 	56
+
+
+Done...
+
+

libraries/DEVNULL/keywords.txt

@@ -1,13 +1,12 @@
 # Syntax Colouring Map For DEVNULL
 
-
 # Data types (KEYWORD1)
 DEVNULL	KEYWORD1
 
-
 # Methods and Functions (KEYWORD2)
 # all known from Stream.
 
+lastByte	KEYWORD2
 
 # Instances (KEYWORD2)
 

libraries/DEVNULL/library.json

@@ -15,7 +15,7 @@
     "type": "git",
     "url": "https://github.com/RobTillaart/DEVNULL.git"
   },
-  "version": "0.1.3",
+  "version": "0.1.4",
   "license": "MIT",
   "frameworks": "arduino",
   "platforms": "*",

libraries/DEVNULL/library.properties

@@ -1,5 +1,5 @@
 name=DEVNULL
-version=0.1.3
+version=0.1.4
 author=Rob Tillaart <rob.tillaart@gmail.com>
 maintainer=Rob Tillaart <rob.tillaart@gmail.com>
 sentence=Arduino library for a /dev/null stream

libraries/DEVNULL/test/unit_test_001.cpp

@@ -44,9 +44,14 @@ unittest(test_all)
   assertEqual(0,   dn.available());
   assertEqual(EOF, dn.peek());
   assertEqual(EOF, dn.read());
+
   assertEqual(1,   dn.write('a'));
+  assertEqual('a', dn.lastByte());
+
   assertEqual(11,  dn.print("hello world"));
+  assertEqual('d', dn.lastByte());
   assertEqual(13,  dn.println("hello world"));
+  assertEqual(10,  dn.lastByte());  //  10 == newline
 }
 
 unittest_main()