package org.tanukisoftware.wrapper; /* * Copyright (c) 1999, 2022 Tanuki Software, Ltd. * http://www.tanukisoftware.com * All rights reserved. * * This software is the proprietary information of Tanuki Software. * You shall use it only in accordance with the terms of the * license agreement you entered into with Tanuki Software. * http://wrapper.tanukisoftware.com/doc/english/licenseOverview.html */ import java.io.ByteArrayInputStream; import java.io.InputStream; import java.io.IOException; /** * The InputStream Class of a WrapperProcess, representing all the data the * ChildProcess writes to the Wrapper. * * @author Tanuki Software Development Team <support@tanukisoftware.com> * @since Wrapper 3.4.0 */ public class WrapperProcessInputStream extends InputStream { /** Platform specific pointer to the underlying native pipe being read from. */ private long m_ptr; /** Flag which keeps track of whether the close method has been called. */ private boolean m_closed; /** Buffer containing all unread data from the pipe. This will only exist if the process terminates before a read method has been called. */ private ByteArrayInputStream m_bais; /** Read flag is set the first time a thread calls any of the read methods. * This is used to decide whther or not pending data in the buffer needs to be stored in m_bais once the process is terminated. * Storing the unread data is necessary if the child process terminates before the use code has a chance to access the InputStreams. */ private boolean m_read; /** Flag which is set when the child process is terminated. Used within native code. */ private volatile boolean m_terminated; /** Indicates if the pipes should be read in a non-blocking mode with check of the m_terminated flag between retries. Used within native code. */ private volatile boolean m_checkTerminated; /** Semaphore to synchronize access to the m_read flag. * It is important that the synchronization is made on a distinct object so that m_read can be accessed while other threads hold a lock on 'this'. */ private Object m_readSm = new Object(); /*--------------------------------------------------------------- * Constructors *-------------------------------------------------------------*/ /** * This class can only be instantiated by native code. */ private WrapperProcessInputStream() { } /*--------------------------------------------------------------- * Native Methods *-------------------------------------------------------------*/ private native int nativeRead( boolean blocking ); private native void nativeClose(); private native int nativeRead2( byte[] b, int off, int len ); /*--------------------------------------------------------------- * Methods *-------------------------------------------------------------*/ /** * Closes the InputStream * @throws IOException in case of any file errors * @throws WrapperLicenseError If the function is called other than in * the Professional Edition or from a Standalone JVM. */ public void close() throws IOException { synchronized( this ) { if ( !m_closed ) { if ( WrapperManager.isNativeLibraryOk() ) { nativeClose(); } m_closed = true; } } } /** * Tests if this input stream supports the mark and reset methods. * * The markSupported method of InputStream returns false. * * @return false. */ public boolean markSupported() { return false; } /** * @return TRUE if ready, otherwise FALSE. */ public boolean ready() { synchronized( this ) { if ( !m_closed || ( ( m_bais != null ) && ( m_bais.available() > 0 ) ) ) { return true; } else { return false; } } } /** * Read a character from the Stream and moves the position in the stream * * @return A single character from the stream, or -1 when the end of stream is reached. * * @throws IOException in case the stream has been already closed or any other file error * @throws WrapperLicenseError If the function is called other than in * the Professional Edition or from a Standalone JVM. */ public int read() throws IOException { if ( !m_read ) { synchronized ( m_readSm ) { m_read = true; } } synchronized( this ) { if ( ( !m_closed ) && WrapperManager.isNativeLibraryOk() ) { return nativeRead( true ); } else { if ( m_bais != null ) { return m_bais.read(); } else { throw new IOException( WrapperManager.getRes().getString( "Stream is closed." ) ); } } } } /** * Reads some number of bytes from the input stream and stores them into the buffer array b. * The number of bytes actually read is returned as an integer. This method blocks until input * data is available, end of file is detected, or an exception is thrown. * * If the length of b is zero, then no bytes are read and 0 is returned; otherwise, there is an * attempt to read at least one byte. If no byte is available because the stream is at the end * of the file, the value -1 is returned; otherwise, at least one byte is read and stored into b. * * The first byte read is stored into element b[0], the next one into b[1], and so on. The number * of bytes read is, at most, equal to the length of b. Let k be the number of bytes actually * read; these bytes will be stored in elements b[0] through b[k-1], leaving elements b[k] * through b[b.length-1] unaffected. * * The read(b) method for class InputStream has the same effect as: * * read(b, 0, b.length) * * @param b The buffer into which the data is read. * * @return The total number of bytes read into the buffer, or -1 is there is no more data because * the end of the stream has been reached. * * @throws IOException If the first byte cannot be read for any reason other than the end of the * file, if the input stream has been closed, or if some other I/O error * occurs. * @throws WrapperLicenseError If the function is called other than in * the Professional Edition or from a Standalone JVM. */ public int read( byte b[ ] ) throws IOException { return read( b, 0, b.length ); } /** * Reads up to len bytes of data from the input stream into an array of bytes. An attempt is made * to read as many as len bytes, but a smaller number may be read. The number of bytes actually * read is returned as an integer. * * This method blocks until input data is available, end of file is detected, or an exception is * thrown. * * If len is zero, then no bytes are read and 0 is returned; otherwise, there is an attempt to * read at least one byte. If no byte is available because the stream is at end of file, the * value -1 is returned; otherwise, at least one byte is read and stored into b. * * The first byte read is stored into element b[off], the next one into b[off+1], and so on. The * number of bytes read is, at most, equal to len. Let k be the number of bytes actually read; * these bytes will be stored in elements b[off] through b[off+k-1], leaving elements b[off+k] * through b[off+len-1] unaffected. * * In every case, elements b[0] through b[off] and elements b[off+len] through b[b.length-1] are * unaffected. * * @param b The buffer into which the data is read. * @param off The start offset in array b from which the data is read. * @param len The maximum number of bytes to read. * * @return The total number of bytes read into the buffer, or -1 is there is no more data because * the end of the stream has been reached. * * @throws IOException If the first byte cannot be read for any reason other than the end of the * file, if the input stream has been closed, or if some other I/O error * occurs. * @throws WrapperLicenseError If the function is called other than in * the Professional Edition or from a Standalone JVM. */ public int read( byte b[], int off, int len ) throws IOException { if ( !m_read ) { synchronized ( m_readSm ) { m_read = true; } } synchronized ( this ) { if ( b == null ) { throw new NullPointerException(); } else if ( ( off < 0 ) || ( len < 0 ) || ( len > b.length - off ) ) { throw new IndexOutOfBoundsException(); } else if ( len == 0 ) { return 0; } if ( !ready() ) { return -1; } int result; if ( ( !m_closed ) && WrapperManager.isNativeLibraryOk() ) { result = nativeRead2( b, off, len ); } else { if ( m_bais != null ) { result = m_bais.read( b, off, len ); } else { throw new IOException(WrapperManager.getRes().getString( "Stream is closed." ) ); } } return result; } } /*--------------------------------------------------------------- * Private Methods *-------------------------------------------------------------*/ /** * This method gets called when a spawned Process has terminated * and the pipe buffer gets read and stored in an byte array. * This way we can close the Filedescriptor and keep the number * of open FDs as small as possible. */ private void readAndCloseOpenFDs() { // Set the terminated flag. This must be done even when read has already been called. // It is also important that this be set even if another thread is currently reading. m_terminated = true; synchronized ( m_readSm ) { if ( m_read ) { // Another thread is reading from the stream so we can trust that thread to complete the reads and close on its own. return; } } synchronized( this ) { int count; int msg; if ( m_closed || ( !WrapperManager.isNativeLibraryOk() ) ) { return; } try { byte[] buffer = new byte[1024]; count = 0; while ( ( msg = nativeRead( false ) ) != -1 ) { if ( count >= buffer.length ) { byte[] temp = new byte[buffer.length + 1024]; System.arraycopy( buffer, 0, temp, 0, buffer.length ); buffer = temp; } buffer[count++] = (byte)msg; } m_bais = new ByteArrayInputStream( buffer, 0, count ); close(); } catch( IOException ioe ) { System.out.println( WrapperManager.getRes().getString( "WrapperProcessStream encountered a ReadError: " ) ); ioe.printStackTrace(); } } } }