382 lines
11 KiB
Plaintext
382 lines
11 KiB
Plaintext
/*----------------------------------------------------------------------
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Compiler Generator Coco/R,
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Copyright (c) 1990, 2004 Hanspeter Moessenboeck, University of Linz
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extended by M. Loeberbauer & A. Woess, Univ. of Linz
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with improvements by Pat Terry, Rhodes University
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This program is free software; you can redistribute it and/or modify it
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under the terms of the GNU General Public License as published by the
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Free Software Foundation; either version 2, or (at your option) any
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later version.
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This program is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
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or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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for more details.
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You should have received a copy of the GNU General Public License along
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with this program; if not, write to the Free Software Foundation, Inc.,
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59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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As an exception, it is allowed to write an extension of Coco/R that is
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used as a plugin in non-free software.
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If not otherwise stated, any source code generated by Coco/R (other than
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Coco/R itself) does not fall under the GNU General Public License.
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-----------------------------------------------------------------------*/
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-->begin
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using System;
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using System.IO;
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using System.Collections;
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-->namespace
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public class Token {
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public int kind; // token kind
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public int pos; // token position in bytes in the source text (starting at 0)
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public int charPos; // token position in characters in the source text (starting at 0)
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public int col; // token column (starting at 1)
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public int line; // token line (starting at 1)
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public string val; // token value
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public Token next; // ML 2005-03-11 Tokens are kept in linked list
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}
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//-----------------------------------------------------------------------------------
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// Buffer
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//-----------------------------------------------------------------------------------
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public class Buffer {
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// This Buffer supports the following cases:
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// 1) seekable stream (file)
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// a) whole stream in buffer
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// b) part of stream in buffer
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// 2) non seekable stream (network, console)
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public const int EOF = char.MaxValue + 1;
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const int MIN_BUFFER_LENGTH = 1024; // 1KB
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const int MAX_BUFFER_LENGTH = MIN_BUFFER_LENGTH * 64; // 64KB
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byte[] buf; // input buffer
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int bufStart; // position of first byte in buffer relative to input stream
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int bufLen; // length of buffer
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int fileLen; // length of input stream (may change if the stream is no file)
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int bufPos; // current position in buffer
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Stream stream; // input stream (seekable)
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bool isUserStream; // was the stream opened by the user?
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public Buffer (Stream s, bool isUserStream) {
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stream = s; this.isUserStream = isUserStream;
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if (stream.CanSeek) {
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fileLen = (int) stream.Length;
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bufLen = Math.Min(fileLen, MAX_BUFFER_LENGTH);
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bufStart = Int32.MaxValue; // nothing in the buffer so far
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} else {
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fileLen = bufLen = bufStart = 0;
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}
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buf = new byte[(bufLen>0) ? bufLen : MIN_BUFFER_LENGTH];
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if (fileLen > 0) Pos = 0; // setup buffer to position 0 (start)
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else bufPos = 0; // index 0 is already after the file, thus Pos = 0 is invalid
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if (bufLen == fileLen && stream.CanSeek) Close();
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}
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protected Buffer(Buffer b) { // called in UTF8Buffer constructor
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buf = b.buf;
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bufStart = b.bufStart;
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bufLen = b.bufLen;
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fileLen = b.fileLen;
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bufPos = b.bufPos;
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stream = b.stream;
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// keep destructor from closing the stream
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b.stream = null;
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isUserStream = b.isUserStream;
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}
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~Buffer() { Close(); }
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protected void Close() {
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if (!isUserStream && stream != null) {
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stream.Close();
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stream = null;
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}
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}
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public virtual int Read () {
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if (bufPos < bufLen) {
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return buf[bufPos++];
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} else if (Pos < fileLen) {
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Pos = Pos; // shift buffer start to Pos
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return buf[bufPos++];
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} else if (stream != null && !stream.CanSeek && ReadNextStreamChunk() > 0) {
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return buf[bufPos++];
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} else {
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return EOF;
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}
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}
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public int Peek () {
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int curPos = Pos;
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int ch = Read();
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Pos = curPos;
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return ch;
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}
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// beg .. begin, zero-based, inclusive, in byte
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// end .. end, zero-based, exclusive, in byte
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public string GetString (int beg, int end) {
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int len = 0;
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char[] buf = new char[end - beg];
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int oldPos = Pos;
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Pos = beg;
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while (Pos < end) buf[len++] = (char) Read();
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Pos = oldPos;
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return new String(buf, 0, len);
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}
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public int Pos {
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get { return bufPos + bufStart; }
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set {
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if (value >= fileLen && stream != null && !stream.CanSeek) {
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// Wanted position is after buffer and the stream
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// is not seek-able e.g. network or console,
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// thus we have to read the stream manually till
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// the wanted position is in sight.
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while (value >= fileLen && ReadNextStreamChunk() > 0);
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}
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if (value < 0 || value > fileLen) {
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throw new FatalError("buffer out of bounds access, position: " + value);
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}
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if (value >= bufStart && value < bufStart + bufLen) { // already in buffer
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bufPos = value - bufStart;
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} else if (stream != null) { // must be swapped in
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stream.Seek(value, SeekOrigin.Begin);
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bufLen = stream.Read(buf, 0, buf.Length);
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bufStart = value; bufPos = 0;
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} else {
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// set the position to the end of the file, Pos will return fileLen.
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bufPos = fileLen - bufStart;
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}
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}
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}
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// Read the next chunk of bytes from the stream, increases the buffer
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// if needed and updates the fields fileLen and bufLen.
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// Returns the number of bytes read.
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private int ReadNextStreamChunk() {
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int free = buf.Length - bufLen;
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if (free == 0) {
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// in the case of a growing input stream
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// we can neither seek in the stream, nor can we
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// foresee the maximum length, thus we must adapt
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// the buffer size on demand.
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byte[] newBuf = new byte[bufLen * 2];
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Array.Copy(buf, newBuf, bufLen);
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buf = newBuf;
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free = bufLen;
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}
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int read = stream.Read(buf, bufLen, free);
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if (read > 0) {
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fileLen = bufLen = (bufLen + read);
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return read;
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}
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// end of stream reached
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return 0;
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}
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}
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//-----------------------------------------------------------------------------------
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// UTF8Buffer
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//-----------------------------------------------------------------------------------
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public class UTF8Buffer: Buffer {
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public UTF8Buffer(Buffer b): base(b) {}
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public override int Read() {
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int ch;
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do {
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ch = base.Read();
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// until we find a utf8 start (0xxxxxxx or 11xxxxxx)
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} while ((ch >= 128) && ((ch & 0xC0) != 0xC0) && (ch != EOF));
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if (ch < 128 || ch == EOF) {
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// nothing to do, first 127 chars are the same in ascii and utf8
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// 0xxxxxxx or end of file character
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} else if ((ch & 0xF0) == 0xF0) {
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// 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
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int c1 = ch & 0x07; ch = base.Read();
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int c2 = ch & 0x3F; ch = base.Read();
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int c3 = ch & 0x3F; ch = base.Read();
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int c4 = ch & 0x3F;
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ch = (((((c1 << 6) | c2) << 6) | c3) << 6) | c4;
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} else if ((ch & 0xE0) == 0xE0) {
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// 1110xxxx 10xxxxxx 10xxxxxx
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int c1 = ch & 0x0F; ch = base.Read();
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int c2 = ch & 0x3F; ch = base.Read();
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int c3 = ch & 0x3F;
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ch = (((c1 << 6) | c2) << 6) | c3;
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} else if ((ch & 0xC0) == 0xC0) {
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// 110xxxxx 10xxxxxx
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int c1 = ch & 0x1F; ch = base.Read();
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int c2 = ch & 0x3F;
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ch = (c1 << 6) | c2;
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}
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return ch;
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}
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}
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//-----------------------------------------------------------------------------------
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// Scanner
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//-----------------------------------------------------------------------------------
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public class Scanner {
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const char EOL = '\n';
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const int eofSym = 0; /* pdt */
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-->declarations
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public Buffer buffer; // scanner buffer
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Token t; // current token
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int ch; // current input character
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int pos; // byte position of current character
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int charPos; // position by unicode characters starting with 0
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int col; // column number of current character
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int line; // line number of current character
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int oldEols; // EOLs that appeared in a comment;
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static readonly Hashtable start; // maps first token character to start state
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Token tokens; // list of tokens already peeked (first token is a dummy)
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Token pt; // current peek token
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char[] tval = new char[128]; // text of current token
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int tlen; // length of current token
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static Scanner() {
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start = new Hashtable(128);
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-->initialization
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}
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public Scanner (string fileName) {
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try {
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Stream stream = new FileStream(fileName, FileMode.Open, FileAccess.Read, FileShare.Read);
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buffer = new Buffer(stream, false);
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Init();
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} catch (IOException) {
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throw new FatalError("Cannot open file " + fileName);
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}
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}
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public Scanner (Stream s) {
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buffer = new Buffer(s, true);
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Init();
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}
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void Init() {
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pos = -1; line = 1; col = 0; charPos = -1;
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oldEols = 0;
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NextCh();
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if (ch == 0xEF) { // check optional byte order mark for UTF-8
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NextCh(); int ch1 = ch;
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NextCh(); int ch2 = ch;
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if (ch1 != 0xBB || ch2 != 0xBF) {
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throw new FatalError(String.Format("illegal byte order mark: EF {0,2:X} {1,2:X}", ch1, ch2));
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}
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buffer = new UTF8Buffer(buffer); col = 0; charPos = -1;
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NextCh();
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}
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pt = tokens = new Token(); // first token is a dummy
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}
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void NextCh() {
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if (oldEols > 0) { ch = EOL; oldEols--; }
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else {
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pos = buffer.Pos;
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// buffer reads unicode chars, if UTF8 has been detected
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ch = buffer.Read(); col++; charPos++;
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// replace isolated '\r' by '\n' in order to make
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// eol handling uniform across Windows, Unix and Mac
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if (ch == '\r' && buffer.Peek() != '\n') ch = EOL;
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if (ch == EOL) { line++; col = 0; }
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}
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-->casing1
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}
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void AddCh() {
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if (tlen >= tval.Length) {
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char[] newBuf = new char[2 * tval.Length];
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Array.Copy(tval, 0, newBuf, 0, tval.Length);
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tval = newBuf;
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}
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if (ch != Buffer.EOF) {
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-->casing2
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NextCh();
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}
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}
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-->comments
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void CheckLiteral() {
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-->literals
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}
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Token NextToken() {
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while (ch == ' ' ||
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-->scan1
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) NextCh();
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-->scan2
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int recKind = noSym;
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int recEnd = pos;
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t = new Token();
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t.pos = pos; t.col = col; t.line = line; t.charPos = charPos;
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int state;
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if (start.ContainsKey(ch)) { state = (int) start[ch]; }
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else { state = 0; }
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tlen = 0; AddCh();
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switch (state) {
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case -1: { t.kind = eofSym; break; } // NextCh already done
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case 0: {
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if (recKind != noSym) {
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tlen = recEnd - t.pos;
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SetScannerBehindT();
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}
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t.kind = recKind; break;
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} // NextCh already done
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-->scan3
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}
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t.val = new String(tval, 0, tlen);
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return t;
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}
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private void SetScannerBehindT() {
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buffer.Pos = t.pos;
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NextCh();
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line = t.line; col = t.col; charPos = t.charPos;
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for (int i = 0; i < tlen; i++) NextCh();
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}
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// get the next token (possibly a token already seen during peeking)
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public Token Scan () {
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if (tokens.next == null) {
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return NextToken();
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} else {
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pt = tokens = tokens.next;
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return tokens;
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}
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}
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// peek for the next token, ignore pragmas
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public Token Peek () {
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do {
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if (pt.next == null) {
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pt.next = NextToken();
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}
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pt = pt.next;
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} while (pt.kind > maxT); // skip pragmas
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return pt;
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}
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// make sure that peeking starts at the current scan position
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public void ResetPeek () { pt = tokens; }
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} // end Scanner
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