proxmark3/client/graph.c

//-----------------------------------------------------------------------------
// Copyright (C) 2010 iZsh <izsh at fail0verflow.com>
//
// This code is licensed to you under the terms of the GNU GPL, version 2 or,
// at your option, any later version. See the LICENSE.txt file for the text of
// the license.
//-----------------------------------------------------------------------------
// Graph utilities
//-----------------------------------------------------------------------------

#include <stdio.h>
#include <stdbool.h>
#include <string.h>
#include "ui.h"
#include "graph.h"
#include "lfdemod.h"

int GraphBuffer[MAX_GRAPH_TRACE_LEN];
int GraphTraceLen;

/* write a bit to the graph */
void AppendGraph(int redraw, int clock, int bit)
{
  int i;
  int half = (int)(clock/2);
  int firstbit = bit ^ 1;
 
  for (i = 0; i < half; ++i)
    GraphBuffer[GraphTraceLen++] = firstbit;
  
  for (i = 0; i <= half; ++i)
    GraphBuffer[GraphTraceLen++] = bit;

  if (redraw)
    RepaintGraphWindow();
}

/* clear out our graph window */
int ClearGraph(int redraw)
{
  int gtl = GraphTraceLen;
  memset(GraphBuffer, 0x00, GraphTraceLen);

  GraphTraceLen = 0;
 
  if (redraw)
    RepaintGraphWindow();

  return gtl;
}

void SetGraphBuf(uint8_t *buff, int size) 
{
	if ( buff == NULL ) return;
	
	uint16_t i = 0;  
	if ( size > MAX_GRAPH_TRACE_LEN )
		size = MAX_GRAPH_TRACE_LEN;
	ClearGraph(0);
	for (; i < size; ++i){
		GraphBuffer[i] = buff[i];
	}
	GraphTraceLen = size;
	RepaintGraphWindow();
	return;
}

// Copies grahpbuff to buff. 
// while triming values to the range -127 -- 127.
int GetFromGraphBuf(uint8_t *buff)
{
	if ( buff == NULL ) return -1;
	uint32_t i = 0;
	
	for (; i < GraphTraceLen; ++i){
	
		// trim upper and lower values.
		if (GraphBuffer[i] > 127) 
			GraphBuffer[i] = 127;
		else if (GraphBuffer[i] < -127)
			GraphBuffer[i] = -127;
			
		buff[i] = (uint8_t)(GraphBuffer[i] + 128);
	}
	return i;
}
/* Get or auto-detect clock rate */
int GetClock(const char *str, int verbose)
{
	int clock;

	sscanf(str, "%i", &clock);
	if (!strcmp(str, ""))
		clock = 0;

	/* Auto-detect clock */
	if (!clock) {

		uint8_t grph[MAX_GRAPH_TRACE_LEN] = {0x00};
		int size = GetFromGraphBuf(grph);
		if ( size < 0 ) {
			PrintAndLog("Failed to copy from graphbuffer");
			return -1;
		}
		clock = DetectASKClock(grph, size, 0);

		/* Only print this message if we're not looping something */
		if (verbose)
			PrintAndLog("Auto-detected clock rate: %d", clock);
		}
	return clock;
}

// A simple test to see if there is any data inside Graphbuffer. 
bool HasGraphData(){

	if ( GraphTraceLen <= 0) {
		PrintAndLog("No data available, try reading something first");
		return false;
	}
	return true;	
}

// Detect high and lows in Grapbuffer.
// Only loops the first 256 values. 
void DetectHighLowInGraph(int *high, int *low, bool addFuzz) {

	uint8_t loopMax = 255;
	if ( loopMax > GraphTraceLen)
		loopMax = GraphTraceLen;
  
	for (uint8_t i = 0; i < loopMax; ++i) {
		if (GraphBuffer[i] > *high)
			*high = GraphBuffer[i];
		else if (GraphBuffer[i] < *low)
			*low = GraphBuffer[i];
	}
	
	//12% fuzz in case highs and lows aren't clipped
	if (addFuzz) {
		*high = (int)(*high * .88);
		*low  = (int)(*low  * .88);
	}
}