IntCameraParameter.cpp

/*----------------------------------------------------------------------------*/
/* Copyright (c) FIRST 2008. All Rights Reserved.                                                         */
/* Open Source Software - may be modified and shared by FRC teams. The code   */
/* must be accompanied by the FIRST BSD license file in $(WIND_BASE)/WPILib.  */
/*----------------------------------------------------------------------------*/

#include "IntCameraParameter.h"
#include "pcre.h"
#include <stdio.h>
#include <string.h>

IntCameraParameter::IntCameraParameter(const char *setString, const char *getString, bool requiresRestart)
{
        m_changed = false;
        m_value = 0;
        m_setString = setString;
        m_getString = getString;
        m_requiresRestart = requiresRestart;
}

int IntCameraParameter::GetValue()
{
        return m_value;
}

void IntCameraParameter::SetValue(int value)
{
        m_value = value;
        m_changed = true;
}

bool IntCameraParameter::CheckChanged(bool &changed, char *param)
{
        changed = m_changed;
        if (m_changed)
        {
                sprintf(param, m_setString, m_value);
                m_changed = false;
                return m_requiresRestart;
        }
        return false;
}

void IntCameraParameter::GetParamFromString(const char *string, int stringLength)
{
        char resultString[150];
        if (SearchForParam(m_getString, string, stringLength, resultString) >= 0)
        {       
                if (!m_changed) m_value = atoi(resultString);
        }
}

int IntCameraParameter::SearchForParam(const char *pattern, const char *searchString, int searchStringLen, char *result)
{
        int vectorLen = 10;
        int resultVector[vectorLen];
        const char *error;
        int erroffset;
        pcre *compiledPattern = pcre_compile(
                        pattern, //"root.Image.I0.Appearance.Resolution=(.*)", 
                        PCRE_CASELESS, 
                        &error, // for error message 
                        &erroffset, // for error offset 
                        NULL); // use default character tables 
        int rc;
        rc = pcre_exec(compiledPattern, 
                                        NULL, 
                                        searchString, 
                                        searchStringLen, 
                                        0, 
                                        0, 
                                        resultVector,           //locations of submatches 
                                        vectorLen);                     //size of ovector
        int length = resultVector[3] - resultVector[2];
        memcpy(result, &searchString[resultVector[2]], length);
        result[length] = '\0';
        return rc;
}