opportunistic-xbee/lcd.h

#ifndef _LCD_H_
	#define _LCD_H_

	#include <LiquidCrystal_I2C.h>

	#define BUFSIZE 64

	class LCDWrapper : public LiquidCrystal_I2C{

		private:
			uint8_t rows, cols;
			char* buffer = NULL;


		public:
			LCDWrapper(uint8_t addr, uint8_t cols, uint8_t rows, uint8_t charsize=LCD_5x8DOTS) : LiquidCrystal_I2C(addr,cols,rows,charsize) {
				this->cols = cols;
				this->rows = rows;
			}

			void begin(){
				LiquidCrystal_I2C::begin();
				LiquidCrystal_I2C::backlight();
			}

			void printfn(const uint8_t line, const char *fmt, ...){
				buffer = (char*) malloc( BUFSIZE * sizeof(char*));
				buffer[0] = 0;

				va_list ap;
				va_start(ap, fmt);
				int size = vsnprintf(buffer, BUFSIZE, fmt, ap);
				va_end(ap);
				if( size < 0 || size >= BUFSIZE ){ free(buffer); return; }

				LiquidCrystal_I2C::setCursor(0, line);
				LiquidCrystal_I2C::print(buffer);
				free(buffer);
			}

			void printfn_overflow(const uint8_t line, const char *fmt, ...){
				buffer = (char*) malloc( BUFSIZE * sizeof(char*));
				buffer[0] = 0;

				va_list ap;
				va_start(ap, fmt);
				int size = vsnprintf(buffer, BUFSIZE, fmt, ap);
				va_end(ap);
				buffer[BUFSIZE-1] = 0;
				if( size < 0 || size >= BUFSIZE ){ free(buffer); return; }


				LiquidCrystal_I2C::setCursor(0,line);
				LiquidCrystal_I2C::print(buffer);
				if( size <= cols ){ free(buffer); return; }

				for( uint8_t offset = 1 ; offset <= size-cols ; offset++ ){
					delay(200);
					LiquidCrystal_I2C::setCursor(0,line);
					LiquidCrystal_I2C::print(buffer+offset);
				}
				free(buffer);
			}

		protected:
			void printf(const char *fmt, ...) {
				buffer = (char*) malloc( BUFSIZE * sizeof(char*));
				buffer[0] = 0;

				va_list ap;
				va_start(ap, fmt);
				int size = vsnprintf(buffer, BUFSIZE, fmt, ap);
				va_end(ap);
				if( size < 0 || size >= BUFSIZE ){ free(buffer); return; }

				LiquidCrystal_I2C::print(buffer);
				free(buffer);
			}
	};

#endif