Move CharBuffer class into its own file so it can be shared by (#300)

power_board and telemetry_board sketches.

resources/arduino_files/power_board/CharBuffer.h

@@ -0,0 +1 @@
+../shared/CharBuffer.h

resources/arduino_files/power_board/power_board.ino

@@ -3,6 +3,7 @@
 #include "OneWire.h"
 #include "DallasTemperature.h"
 #include "DHT.h"
+#include "CharBuffer.h"
 
 #define DHTTYPE DHT22   // DHT 22  (AM2302)
 
@@ -84,61 +85,6 @@ void setup() {
   digitalWrite(DSEL_1, LOW); // DSEL_1 LOW reads PROFET 1_0. DSEL_1 HIGH reades PROFET 1_1  
 }
 
-// CharBuffer stores characters and supports (minimal) parsing of
-// the buffered characters.
-template <uint8_t kBufferSize>
-class CharBuffer {
-  public:
-    CharBuffer() {
-      Reset();
-    }
-    void Reset() {
-      write_cursor_ = read_cursor_ = 0;
-    }
-    bool Append(char c) {
-      if (write_cursor_ < kBufferSize) {
-        buf_[write_cursor_++] = c;
-        return true;
-      }
-      return false;
-    }
-    bool Empty() {
-      return read_cursor_ >= write_cursor_;
-    }
-    char Next() {
-      return buf_[read_cursor_++];
-    }
-    char Peek() {
-      return buf_[read_cursor_];
-    }
-    bool ParseInt(int* output) {
-      int& v = *output;
-      v = 0;
-      size_t len = 0;
-      while (!Empty() && isdigit(Peek())) {
-        char c = Next();
-        v = v * 10 + c - '0';
-        ++len;
-        if (len > 5) {
-          return false;
-        }
-      }
-      return len > 0;
-    }
-    bool MatchAndConsume(char c) {
-      if (Empty() || Peek() != c) {
-        return false;
-      }
-      Next();
-      return true;
-    }
-
-  private:
-    char buf_[kBufferSize];
-    uint8_t write_cursor_;
-    uint8_t read_cursor_;
-};
-
 // Accumulates a line, parses it and takes the requested action if it is valid.
 class SerialInputHandler {
   public:
@@ -172,10 +118,10 @@ class SerialInputHandler {
     }
 
     void ProcessInputBuffer() {
-      int relay_index, new_state;
-      if (input_buffer_.ParseInt(&relay_index) &&
+      uint8_t relay_index, new_state;
+      if (input_buffer_.ParseUInt8(&relay_index) &&
           input_buffer_.MatchAndConsume(',') &&
-          input_buffer_.ParseInt(&new_state) &&
+          input_buffer_.ParseUInt8(&new_state) &&
           input_buffer_.Empty()) {
 
         int pin_num = relayArray[relay_index];

resources/arduino_files/shared/CharBuffer.h

@@ -0,0 +1,63 @@
+// CharBuffer stores characters and supports (minimal) parsing of
+// the buffered characters.
+template <uint8_t kBufferSize>
+class CharBuffer {
+  public:
+    CharBuffer() {
+      Reset();
+    }
+    void Reset() {
+      write_cursor_ = read_cursor_ = 0;
+    }
+    // Appends a character to the buffer if there is room.
+    // Returns true if there is room, else returns false.
+    bool Append(char c) {
+      if (write_cursor_ < kBufferSize) {
+        buf_[write_cursor_++] = c;
+        return true;
+      }
+      return false;
+    }
+    bool Empty() {
+      return read_cursor_ >= write_cursor_;
+    }
+    char Next() {
+      return buf_[read_cursor_++];
+    }
+    char Peek() {
+      return buf_[read_cursor_];
+    }
+    // Parses the integer (uint8_t) in buffer starting at read_cursor_.
+    // The integer must be non-negative (leading + or - are not supported).
+    // Returns true if successful, false if there is not an integer at
+    // read_cursor_ or if the integer is too big to fit into *output.
+    bool ParseUInt8(uint8_t* output) {
+      uint16_t v = 0;
+      uint8_t len = 0;
+      while (!Empty() && isdigit(Peek())) {
+        char c = Next();
+        v = v * 10 + c - '0';
+        ++len;
+        if (len > 3) {
+          return false;
+        }
+      }
+      if (len == 0 || v > 255) {
+        return false;
+      }
+      *output = static_cast<uint8_t>(v);
+      return true;
+    }
+    bool MatchAndConsume(char c) {
+      if (Empty() || Peek() != c) {
+        return false;
+      }
+      Next();
+      return true;
+    }
+
+  private:
+    char buf_[kBufferSize];
+    uint8_t write_cursor_;
+    uint8_t read_cursor_;
+};

resources/arduino_files/telemetry_board/CharBuffer.h

@@ -0,0 +1 @@
+../shared/CharBuffer.h

resources/arduino_files/telemetry_board/telemetry_board.ino

@@ -27,6 +27,7 @@
 #include "OneWire.h"
 #include "DallasTemperature.h"
 #include "DHT.h"
+#include "CharBuffer.h"
 
 ////////////////////////////////////////////////
 // __      __               _                 //
@@ -392,61 +393,6 @@ void Report(unsigned long now) {
 //////////////////////////////////////////////////////////////////////////////////
 // Serial input support
 
-// CharBuffer stores characters and supports (minimal) parsing of
-// the buffered characters.
-template <uint8_t kBufferSize>
-class CharBuffer {
-  public:
-    CharBuffer() {
-      Reset();
-    }
-    void Reset() {
-      write_cursor_ = read_cursor_ = 0;
-    }
-    bool Append(char c) {
-      if (write_cursor_ < kBufferSize) {
-        buf_[write_cursor_++] = c;
-        return true;
-      }
-      return false;
-    }
-    bool Empty() {
-      return read_cursor_ >= write_cursor_;
-    }
-    char Next() {
-      return buf_[read_cursor_++];
-    }
-    char Peek() {
-      return buf_[read_cursor_];
-    }
-    bool ParseInt(int* output) {
-      int& v = *output;
-      v = 0;
-      size_t len = 0;
-      while (!Empty() && isdigit(Peek())) {
-        char c = Next();
-        v = v * 10 + c - '0';
-        ++len;
-        if (len > 5) {
-          return false;
-        }
-      }
-      return len > 0;
-    }
-    bool MatchAndConsume(char c) {
-      if (Empty() || Peek() != c) {
-        return false;
-      }
-      Next();
-      return true;
-    }
-
-  private:
-    char buf_[kBufferSize];
-    uint8_t write_cursor_;
-    uint8_t read_cursor_;
-};
-
 // Accumulates a line, parses it and takes the requested action if it is valid.
 class SerialInputHandler {
   public:
@@ -480,10 +426,10 @@ class SerialInputHandler {
     }
 
     void ProcessInputBuffer() {
-      int pin_num, pin_status;
-      if (input_buffer_.ParseInt(&pin_num) &&
+      uint8_t pin_num, pin_status;
+      if (input_buffer_.ParseUInt8(&pin_num) &&
           input_buffer_.MatchAndConsume(',') &&
-          input_buffer_.ParseInt(&pin_status) &&
+          input_buffer_.ParseUInt8(&pin_status) &&
           input_buffer_.Empty()) {
         switch (pin_num) {
           case COMP_RELAY: