poppler/PSTokenizer.cc

//========================================================================
//
// PSTokenizer.cc
//
// Copyright 2002-2003 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 Scott Turner <scotty1024@mac.com>
// Copyright (C) 2008 Albert Astals Cid <aacid@kde.org>
// Copyright (C) 2017 Vincent Le Garrec <legarrec.vincent@gmail.com>
//
// 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
//
//========================================================================

#include <config.h>

#include <cstdio>
#include <cstdlib>
#include "PSTokenizer.h"

//------------------------------------------------------------------------

// A '1' in this array means the character is white space.  A '1' or
// '2' means the character ends a name or command.
static const char specialChars[256] = {
    1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 1, 0, 0, // 0x
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 1x
    1, 0, 0, 0, 0, 2, 0, 0, 2, 2, 0, 0, 0, 0, 0, 2, // 2x
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 2, 0, // 3x
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 4x
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 2, 0, 0, // 5x
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 6x
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 2, 0, 0, // 7x
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 8x
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 9x
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // ax
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // bx
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // cx
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // dx
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // ex
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 // fx
};

//------------------------------------------------------------------------

PSTokenizer::PSTokenizer(int (*getCharFuncA)(void *), void *dataA)
{
    getCharFunc = getCharFuncA;
    data = dataA;
    charBuf = -1;
}

PSTokenizer::~PSTokenizer() { }

bool PSTokenizer::getToken(char *buf, int size, int *length)
{
    bool comment, backslash;
    int c;
    int i;

    // skip leading whitespace and comments
    comment = false;
    while (true) {
        if ((c = getChar()) == EOF) {
            buf[0] = '\0';
            *length = 0;
            return false;
        }
        if (comment) {
            if (c == '\x0a' || c == '\x0d') {
                comment = false;
            }
        } else if (c == '%') {
            comment = true;
        } else if (specialChars[static_cast<unsigned char>(c)] != 1) {
            break;
        }
    }

    // Reserve room for terminating '\0'
    size--;

    // read a token
    i = 0;
    buf[i++] = c;
    if (c == '(') {
        backslash = false;
        while ((c = lookChar()) != EOF) {
            consumeChar();
            if (i < size) {
                buf[i++] = c;
            }
            if (c == '\\') {
                backslash = true;
            } else if (!backslash && c == ')') {
                break;
            } else {
                backslash = false;
            }
        }
    } else if (c == '<') {
        while ((c = lookChar()) != EOF) {
            consumeChar();
            if (i < size && specialChars[static_cast<unsigned char>(c)] != 1) {
                buf[i++] = c;
            }
            if (c == '>') {
                break;
            }
        }
    } else if (c != '[' && c != ']') {
        while ((c = lookChar()) != EOF && !specialChars[static_cast<unsigned char>(c)]) {
            consumeChar();
            if (i < size) {
                buf[i++] = c;
            }
        }
    }
    // Zero terminate token string
    buf[i] = '\0';
    // Return length of token
    *length = i;

    return true;
}

int PSTokenizer::lookChar()
{
    if (charBuf < 0) {
        charBuf = (*getCharFunc)(data);
    }
    return charBuf;
}

void PSTokenizer::consumeChar()
{
    charBuf = -1;
}

int PSTokenizer::getChar()
{
    int c = charBuf;

    if (c < 0) {
        c = (*getCharFunc)(data);
    } else {
        charBuf = -1;
    }
    return c;
}