/* TEMPLATE GENERATED TESTCASE FILE
Filename: CWE191_Integer_Underflow__int_File_predec_45.java
Label Definition File: CWE191_Integer_Underflow__int.label.xml
Template File: sources-sinks-45.tmpl.java
*/
/*
 * @description
 * CWE: 191 Integer Underflow
 * BadSource: File Read data from file (named c:\data.txt)
 * GoodSource: A hardcoded non-zero, non-min, non-max, even number
 * Sinks: decrement
 *    GoodSink: Ensure there will not be an underflow before decrementing data
 *    BadSink : Decrement data, which can cause an Underflow
 * Flow Variant: 45 Data flow: data passed as a private class member variable from one function to another in the same class
 *
 * */

package testcases.CWE191_Integer_Underflow.s05;
import testcasesupport.*;

import javax.servlet.http.*;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.FileInputStream;
import java.io.File;
import java.io.IOException;

import java.util.logging.Level;

public class CWE191_Integer_Underflow__int_File_predec_45 extends AbstractTestCase
{
    private int dataBad;
    private int dataGoodG2B;
    private int dataGoodB2G;

    private void badSink() throws Throwable
    {
        int data = dataBad;

        /* POTENTIAL FLAW: if data == Integer.MIN_VALUE, this will overflow */
        int result = (int)(--data);

        IO.writeLine("result: " + result);

    }

    public void bad() throws Throwable
    {
        int data;

        data = Integer.MIN_VALUE; /* Initialize data */

        {
            File file = new File("C:\\data.txt");
            FileInputStream streamFileInput = null;
            InputStreamReader readerInputStream = null;
            BufferedReader readerBuffered = null;

            try
            {
                /* read string from file into data */
                streamFileInput = new FileInputStream(file);
                readerInputStream = new InputStreamReader(streamFileInput, "UTF-8");
                readerBuffered = new BufferedReader(readerInputStream);

                /* POTENTIAL FLAW: Read data from a file */
                /* This will be reading the first "line" of the file, which
                 * could be very long if there are little or no newlines in the file */
                String stringNumber = readerBuffered.readLine();
                if (stringNumber != null) /* avoid NPD incidental warnings */
                {
                    try
                    {
                        data = Integer.parseInt(stringNumber.trim());
                    }
                    catch(NumberFormatException exceptNumberFormat)
                    {
                        IO.logger.log(Level.WARNING, "Number format exception parsing data from string", exceptNumberFormat);
                    }
                }
            }
            catch (IOException exceptIO)
            {
                IO.logger.log(Level.WARNING, "Error with stream reading", exceptIO);
            }
            finally
            {
                /* Close stream reading objects */
                try
                {
                    if (readerBuffered != null)
                    {
                        readerBuffered.close();
                    }
                }
                catch (IOException exceptIO)
                {
                    IO.logger.log(Level.WARNING, "Error closing BufferedReader", exceptIO);
                }

                try
                {
                    if (readerInputStream != null)
                    {
                        readerInputStream.close();
                    }
                }
                catch (IOException exceptIO)
                {
                    IO.logger.log(Level.WARNING, "Error closing InputStreamReader", exceptIO);
                }

                try
                {
                    if (streamFileInput != null)
                    {
                        streamFileInput.close();
                    }
                }
                catch (IOException exceptIO)
                {
                    IO.logger.log(Level.WARNING, "Error closing FileInputStream", exceptIO);
                }
            }
        }

        dataBad = data;
        badSink();
    }

    public void good() throws Throwable
    {
        goodG2B();
        goodB2G();
    }

    private void goodG2BSink() throws Throwable
    {
        int data = dataGoodG2B;

        /* POTENTIAL FLAW: if data == Integer.MIN_VALUE, this will overflow */
        int result = (int)(--data);

        IO.writeLine("result: " + result);

    }

    /* goodG2B() - use goodsource and badsink */
    private void goodG2B() throws Throwable
    {
        int data;

        /* FIX: Use a hardcoded number that won't cause underflow, overflow, divide by zero, or loss-of-precision issues */
        data = 2;

        dataGoodG2B = data;
        goodG2BSink();
    }

    private void goodB2GSink() throws Throwable
    {
        int data = dataGoodB2G;

        /* FIX: Add a check to prevent an underflow from occurring */
        if (data > Integer.MIN_VALUE)
        {
            int result = (int)(--data);
            IO.writeLine("result: " + result);
        }
        else
        {
            IO.writeLine("data value is too small to decrement.");
        }

    }

    /* goodB2G() - use badsource and goodsink */
    private void goodB2G() throws Throwable
    {
        int data;

        data = Integer.MIN_VALUE; /* Initialize data */

        {
            File file = new File("C:\\data.txt");
            FileInputStream streamFileInput = null;
            InputStreamReader readerInputStream = null;
            BufferedReader readerBuffered = null;

            try
            {
                /* read string from file into data */
                streamFileInput = new FileInputStream(file);
                readerInputStream = new InputStreamReader(streamFileInput, "UTF-8");
                readerBuffered = new BufferedReader(readerInputStream);

                /* POTENTIAL FLAW: Read data from a file */
                /* This will be reading the first "line" of the file, which
                 * could be very long if there are little or no newlines in the file */
                String stringNumber = readerBuffered.readLine();
                if (stringNumber != null) /* avoid NPD incidental warnings */
                {
                    try
                    {
                        data = Integer.parseInt(stringNumber.trim());
                    }
                    catch(NumberFormatException exceptNumberFormat)
                    {
                        IO.logger.log(Level.WARNING, "Number format exception parsing data from string", exceptNumberFormat);
                    }
                }
            }
            catch (IOException exceptIO)
            {
                IO.logger.log(Level.WARNING, "Error with stream reading", exceptIO);
            }
            finally
            {
                /* Close stream reading objects */
                try
                {
                    if (readerBuffered != null)
                    {
                        readerBuffered.close();
                    }
                }
                catch (IOException exceptIO)
                {
                    IO.logger.log(Level.WARNING, "Error closing BufferedReader", exceptIO);
                }

                try
                {
                    if (readerInputStream != null)
                    {
                        readerInputStream.close();
                    }
                }
                catch (IOException exceptIO)
                {
                    IO.logger.log(Level.WARNING, "Error closing InputStreamReader", exceptIO);
                }

                try
                {
                    if (streamFileInput != null)
                    {
                        streamFileInput.close();
                    }
                }
                catch (IOException exceptIO)
                {
                    IO.logger.log(Level.WARNING, "Error closing FileInputStream", exceptIO);
                }
            }
        }

        dataGoodB2G = data;
        goodB2GSink();
    }

    /* Below is the main(). It is only used when building this testcase on
     * its own for testing or for building a binary to use in testing binary
     * analysis tools. It is not used when compiling all the testcases as one
     * application, which is how source code analysis tools are tested.
     */
    public static void main(String[] args) throws ClassNotFoundException,
           InstantiationException, IllegalAccessException
    {
        mainFromParent(args);
    }
}
