1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
|
//========================================================================
//
// Lexer.h
//
// Copyright 1996-2003 Glyph & Cog, LLC
//
//========================================================================
//========================================================================
//
// Modified under the Poppler project - http://poppler.freedesktop.org
//
// All changes made under the Poppler project to this file are licensed
// under GPL version 2 or later
//
// Copyright (C) 2006, 2007, 2010, 2013 Albert Astals Cid <aacid@kde.org>
// Copyright (C) 2006 Krzysztof Kowalczyk <kkowalczyk@gmail.com>
// Copyright (C) 2013 Adrian Johnson <ajohnson@redneon.com>
// Copyright (C) 2013 Thomas Freitag <Thomas.Freitag@alfa.de>
//
// To see a description of the changes please see the Changelog file that
// came with your tarball or type make ChangeLog if you are building from git
//
//========================================================================
#ifndef LEXER_H
#define LEXER_H
#ifdef USE_GCC_PRAGMAS
#pragma interface
#endif
#include "Object.h"
#include "Stream.h"
class XRef;
#define tokBufSize 128 // size of token buffer
//------------------------------------------------------------------------
// Lexer
//------------------------------------------------------------------------
class Lexer {
public:
// Construct a lexer for a single stream. Deletes the stream when
// lexer is deleted.
Lexer(XRef *xrefA, Stream *str);
// Construct a lexer for a stream or array of streams (assumes obj
// is either a stream or array of streams).
Lexer(XRef *xrefA, Object *obj);
// Destructor.
~Lexer();
// Get the next object from the input stream.
Object *getObj(Object *obj, int objNum = -1);
Object *getObj(Object *obj, const char *cmdA, int objNum);
// Skip to the beginning of the next line in the input stream.
void skipToNextLine();
// Skip over one character.
void skipChar() { getChar(); }
// Get stream.
Stream *getStream()
{ return curStr.isStream() ? curStr.getStream() : (Stream *)NULL; }
// Get current position in file. This is only used for error
// messages.
Goffset getPos()
{ return curStr.isStream() ? curStr.streamGetPos() : -1; }
// Set position in file.
void setPos(Goffset pos, int dir = 0)
{ if (curStr.isStream()) curStr.streamSetPos(pos, dir); }
// Returns true if <c> is a whitespace character.
static GBool isSpace(int c);
// often (e.g. ~30% on PDF Refernce 1.6 pdf file from Adobe site) getChar
// is called right after lookChar. In order to avoid expensive re-doing
// getChar() of underlying stream, we cache the last value found by
// lookChar() in lookCharLastValueCached. A special value
// LOOK_VALUE_NOT_CACHED that should never be part of stream indicates
// that no value was cached
static const int LOOK_VALUE_NOT_CACHED = -3;
int lookCharLastValueCached;
private:
int getChar(GBool comesFromLook = gFalse);
int lookChar();
Array *streams; // array of input streams
int strPtr; // index of current stream
Object curStr; // current stream
GBool freeArray; // should lexer free the streams array?
char tokBuf[tokBufSize]; // temporary token buffer
XRef *xref;
};
#endif
|
