Arduino IDE C/C++

http://codeandlife.com/2012/03/03/diy-usb-password-generator/

Will the IDE accept the old style of code, eg, void setup{} and void loop{} are replaced with while(1) and there is no setup{} so can it be configured to accept code like

/**
 * Project: AVR ATtiny USB Tutorial at http://codeandlife.com/
 * Author: Joonas Pihlajamaa, joonas.pihlajamaa@iki.fi
 * Base on V-USB example code by Christian Starkjohann
 * Copyright: (c) 2008 by OBJECTIVE DEVELOPMENT Software GmbH
 * License: GNU GPL v3 (see License.txt)
 */
#include <avr/io.h>
#include <avr/interrupt.h>
#include <avr/wdt.h>
#include <avr/eeprom.h>
#include <util/delay.h>

#include "usbdrv.h"

// *********************************
// *** BASIC PROGRAM DEFINITIONS ***
// *********************************

#define PASS_LENGTH 10 // password length for generated password
#define SEND_ENTER 0 // define to 1 if you want to send ENTER after password

PROGMEM uchar measuring_message[] = "Starting generation...";
PROGMEM uchar finish_message[] = " New password saved.";

// The buffer needs to accommodate the messages above and the password
#define MSG_BUFFER_SIZE 32 

EEMEM uchar stored_password[MSG_BUFFER_SIZE];


// ************************
// *** USB HID ROUTINES ***
// ************************

// From Frank Zhao's USB Business Card project
// http://www.frank-zhao.com/cache/usbbusinesscard_details.php
PROGMEM char usbHidReportDescriptor[USB_CFG_HID_REPORT_DESCRIPTOR_LENGTH] = {
    0x05, 0x01,                    // USAGE_PAGE (Generic Desktop)
    0x09, 0x06,                    // USAGE (Keyboard)
    0xa1, 0x01,                    // COLLECTION (Application)
    0x75, 0x01,                    //   REPORT_SIZE (1)
    0x95, 0x08,                    //   REPORT_COUNT (8)
    0x05, 0x07,                    //   USAGE_PAGE (Keyboard)(Key Codes)
    0x19, 0xe0,                    //   USAGE_MINIMUM (Keyboard LeftControl)(224)
    0x29, 0xe7,                    //   USAGE_MAXIMUM (Keyboard Right GUI)(231)
    0x15, 0x00,                    //   LOGICAL_MINIMUM (0)
    0x25, 0x01,                    //   LOGICAL_MAXIMUM (1)
    0x81, 0x02,                    //   INPUT (Data,Var,Abs) ; Modifier byte
    0x95, 0x01,                    //   REPORT_COUNT (1)
    0x75, 0x08,                    //   REPORT_SIZE (8)
    0x81, 0x03,                    //   INPUT (Cnst,Var,Abs) ; Reserved byte
    0x95, 0x05,                    //   REPORT_COUNT (5)
    0x75, 0x01,                    //   REPORT_SIZE (1)
    0x05, 0x08,                    //   USAGE_PAGE (LEDs)
    0x19, 0x01,                    //   USAGE_MINIMUM (Num Lock)
    0x29, 0x05,                    //   USAGE_MAXIMUM (Kana)
    0x91, 0x02,                    //   OUTPUT (Data,Var,Abs) ; LED report
    0x95, 0x01,                    //   REPORT_COUNT (1)
    0x75, 0x03,                    //   REPORT_SIZE (3)
    0x91, 0x03,                    //   OUTPUT (Cnst,Var,Abs) ; LED report padding
    0x95, 0x06,                    //   REPORT_COUNT (6)
    0x75, 0x08,                    //   REPORT_SIZE (8)
    0x15, 0x00,                    //   LOGICAL_MINIMUM (0)
    0x25, 0x65,                    //   LOGICAL_MAXIMUM (101)
    0x05, 0x07,                    //   USAGE_PAGE (Keyboard)(Key Codes)
    0x19, 0x00,                    //   USAGE_MINIMUM (Reserved (no event indicated))(0)
    0x29, 0x65,                    //   USAGE_MAXIMUM (Keyboard Application)(101)
    0x81, 0x00,                    //   INPUT (Data,Ary,Abs)
    0xc0                           // END_COLLECTION
};

typedef struct {
	uint8_t modifier;
	uint8_t reserved;
	uint8_t keycode[6];
} keyboard_report_t;

static keyboard_report_t keyboard_report; // sent to PC
volatile static uchar LED_state = 0xff; // received from PC
static uchar idleRate; // repeat rate for keyboards

#define STATE_SEND 1
#define STATE_DONE 0

static uchar messageState = STATE_DONE;
static uchar messageBuffer[MSG_BUFFER_SIZE] = "";
static uchar messagePtr = 0;
static uchar messageCharNext = 1;

#define MOD_SHIFT_LEFT (1<<1)

// The buildReport is called by main loop and it starts transmitting
// characters when messageState == STATE_SEND. The message is stored
// in messageBuffer and messagePtr tells the next character to send.
// Remember to reset messagePtr to 0 after populating the buffer!
uchar buildReport() {
    uchar ch;
    
    if(messageState == STATE_DONE || messagePtr >= sizeof(messageBuffer) || messageBuffer[messagePtr] == 0) {
        keyboard_report.modifier = 0;
        keyboard_report.keycode[0] = 0;
        return STATE_DONE;
    }

    if(messageCharNext) { // send a keypress
        ch = messageBuffer[messagePtr++];
        
        // convert character to modifier + keycode
        if(ch >= '0' && ch <= '9') {
            keyboard_report.modifier = 0;
            keyboard_report.keycode[0] = (ch == '0') ? 39 : 30+(ch-'1');
        } else if(ch >= 'a' && ch <= 'z') {
            keyboard_report.modifier = (LED_state & 2) ? MOD_SHIFT_LEFT : 0;
            keyboard_report.keycode[0] = 4+(ch-'a');
        } else if(ch >= 'A' && ch <= 'Z') {
            keyboard_report.modifier = (LED_state & 2) ? 0 : MOD_SHIFT_LEFT;
            keyboard_report.keycode[0] = 4+(ch-'A');
        } else {
            keyboard_report.modifier = 0;
            keyboard_report.keycode[0] = 0;
            switch(ch) {
			case '.':
				keyboard_report.keycode[0] = 0x37;
				break;
			case '_':
				keyboard_report.modifier = MOD_SHIFT_LEFT;
			case '-':
				keyboard_report.keycode[0] = 0x2D;
				break;
            case ' ':
                keyboard_report.keycode[0] = 0x2C;
                break;
            case '\t':
                keyboard_report.keycode[0] = 0x2B;
                break;
            case '\n':
                keyboard_report.keycode[0] = 0x28;
                break;
            }
        }
    } else { // key release before the next keypress!
        keyboard_report.modifier = 0;
        keyboard_report.keycode[0] = 0;
    }
    
    messageCharNext = !messageCharNext; // invert
    
    return STATE_SEND;
}

//..... more next post

I'm able to use AVRdude and flash the .hex file generated by a donor, but i'm trying to work out how to get this code to work with Arduino?

usbMsgLen_t usbFunctionSetup(uchar data[8]) {
    usbRequest_t *rq = (void *)data;

    if((rq->bmRequestType & USBRQ_TYPE_MASK) == USBRQ_TYPE_CLASS) {
        switch(rq->bRequest) {
        case USBRQ_HID_GET_REPORT: // send "no keys pressed" if asked here
            // wValue: ReportType (highbyte), ReportID (lowbyte)
            usbMsgPtr = (void *)&keyboard_report; // we only have this one
            keyboard_report.modifier = 0;
            keyboard_report.keycode[0] = 0;
            return sizeof(keyboard_report);
		case USBRQ_HID_SET_REPORT: // if wLength == 1, should be LED state
            return (rq->wLength.word == 1) ? USB_NO_MSG : 0;
        case USBRQ_HID_GET_IDLE: // send idle rate to PC as required by spec
            usbMsgPtr = &idleRate;
            return 1;
        case USBRQ_HID_SET_IDLE: // save idle rate as required by spec
            idleRate = rq->wValue.bytes[1];
            return 0;
        }
    }
    
    return 0; // by default don't return any data
}

void caps_toggle(); // defined later in program logic

usbMsgLen_t usbFunctionWrite(uint8_t * data, uchar len) {
	if (data[0] == LED_state)
        return 1;
    else
        LED_state = data[0];
    
    caps_toggle();
	
	return 1; // Data read, not expecting more
}

#define abs(x) ((x) > 0 ? (x) : (-x))

// Called by V-USB after device reset
void hadUsbReset() {
    int frameLength, targetLength = (unsigned)(1499 * (double)F_CPU / 10.5e6 + 0.5);
    int bestDeviation = 9999;
    uchar trialCal, bestCal = 0, step, region;

    // do a binary search in regions 0-127 and 128-255 to get optimum OSCCAL
    for(region = 0; region <= 1; region++) {
        frameLength = 0;
        trialCal = (region == 0) ? 0 : 128;
        
        for(step = 64; step > 0; step >>= 1) { 
            if(frameLength < targetLength) // true for initial iteration
                trialCal += step; // frequency too low
            else
                trialCal -= step; // frequency too high
                
            OSCCAL = trialCal;
            frameLength = usbMeasureFrameLength();
            
            if(abs(frameLength-targetLength) < bestDeviation) {
                bestCal = trialCal; // new optimum found
                bestDeviation = abs(frameLength -targetLength);
            }
        }
    }

    OSCCAL = bestCal;
}


// *********************
// *** PROGRAM LOGIC ***
// *********************

// Routine to return a random character - currently uses the timer 0 as
// a source for randomness - it goes from 0 to 255 over 7800 times a second
// so it should be random enough (remember, this is called after user
// presses caps lock). Of course USB timings may decrease this randomness 
// - replace with a better one if you want.
uchar generate_character() {
    uchar counter = TCNT0 & 63;
    
    if(counter < 26)
        return 'a' + counter;
    else if(counter < 52)
        return 'A' + counter - 26;
    else if(counter < 62)
        return '0' + counter - 52;
    else if(counter == 62)
        return '-';
    else
        return '_';
}

#define CAPS_COUNTING 0
#define CAPS_MEASURING 1

static uchar capsCount = 0;
static uchar capsState = CAPS_COUNTING;

// This routine is called by usbFunctionWrite every time the keyboard LEDs
// toggle - basically we count 4 toggles and then start regenerating
void caps_toggle() {
    if(capsState == CAPS_COUNTING) {    
        if(capsCount++ < 4)
            return;
        
        capsCount = 0;
        capsState = CAPS_MEASURING;

        // Type a message to the PC that we're regenerating the password
        memcpy_P(messageBuffer, measuring_message, sizeof(measuring_message));
        messagePtr = 0;
        messageState = STATE_SEND;
    } else {
        messageBuffer[capsCount++] = generate_character();
        
        if(capsCount >= PASS_LENGTH) { // enough characters generated
#if SEND_ENTER
            messageBuffer[capsCount++] = '\n';
#endif
            messageBuffer[capsCount] = '\0';
            
            // Store password to EEPROM - might lose the USB connection, but so what
            eeprom_write_block(messageBuffer, stored_password, sizeof(messageBuffer));
            
            // Type a message to the PC that new password has been generated
            memcpy_P(messageBuffer, finish_message, sizeof(finish_message));
            messagePtr = 0;
            messageState = STATE_SEND;
            
            capsCount = 0;
            capsState = CAPS_COUNTING;
        }
    }    
}

int main() {
	uchar i;

    // Fetch password from EEPROM and send it
    eeprom_read_block(messageBuffer, stored_password, sizeof(messageBuffer));
    messagePtr = 0;
    messageState = STATE_SEND;
	
    for(i=0; i<sizeof(keyboard_report); i++) // clear report initially
        ((uchar *)&keyboard_report)[i] = 0;
    
    wdt_enable(WDTO_1S); // enable 1s watchdog timer

    usbInit();
	
    usbDeviceDisconnect(); // enforce re-enumeration
    for(i = 0; i<250; i++) { // wait 500 ms
        wdt_reset(); // keep the watchdog happy
        _delay_ms(2);
    }
    usbDeviceConnect();
	
    TCCR0B |= (1 << CS01); // timer 0 at clk/8 will generate randomness
    
    sei(); // Enable interrupts after re-enumeration
	
    while(1) {
        wdt_reset(); // keep the watchdog happy
        usbPoll();
        
        // characters are sent when messageState == STATE_SEND and after receiving
        // the initial LED state from PC (good way to wait until device is recognized)
        if(usbInterruptIsReady() && messageState == STATE_SEND && LED_state != 0xff){
            messageState = buildReport();
            usbSetInterrupt((void *)&keyboard_report, sizeof(keyboard_report));
        }
    }
	
    return 0;
}

cjdelphi:
DIY USB password generator | Code and Life

Will the IDE accept the old style of code, eg, void setup{} and void loop{} are replaced with while(1) and there is no setup{}

Yes. The C++ standard defines variants of main() which the linker will look for (ie. void main(), int main()...etc). All you do is define a main which is higher up the linker's preference then the Arduino main().

Arduino defines main as:

int main()
{
}

So if you define:

int main(int argc,char*argv[])
{
}

The Arduino main will be ignored.

nb. This means functions like millis() won't work because main() initializes the timers for that...

nb. This means functions like millis() won't work because main() initializes the timers for that...

It does so by calling init(), which any other program that overrides main() could also call.

I'll be honest i'm still kinda clueless lol

let's suppose i simply used AVRdude, could I compile, link, whatever and compile/upload straight from cmd line?

cjdelphi:
I'll be honest i'm still kinda clueless lol

let's suppose i simply used AVRdude, could I compile, link, whatever and compile/upload straight from cmd line?

Short version: Declare main the right way and the linker will use it.

int main(int argc,char*argv[])
{
  // I'm the best main()
}

cjdelphi:
I'll be honest i'm still kinda clueless lol

let's suppose i simply used AVRdude, could I compile, link, whatever and compile/upload straight from cmd line?

AVRdude doesn't compile and link - it just uploads a .hex file.

To compile and link you need the avr-gcc and avr-binutils. These are contained in the Arduino IDE, but are also available for separate download.

To work without the IDE, you should google for "Arduino Makefile".