PDFontFactory.java
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.pdfbox.pdmodel.font;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.util.Arrays;
import java.util.List;
import org.apache.pdfbox.cos.COSArray;
import org.apache.pdfbox.cos.COSBase;
import org.apache.pdfbox.cos.COSDictionary;
import org.apache.pdfbox.cos.COSName;
import org.apache.pdfbox.cos.COSStream;
import org.apache.pdfbox.io.RandomAccessRead;
import org.apache.logging.log4j.Logger;
import org.apache.logging.log4j.LogManager;
import org.apache.pdfbox.pdmodel.ResourceCache;
/**
* Creates the appropriate font subtype based on information in the dictionary.
* @author Ben Litchfield
*/
public final class PDFontFactory
{
private static final Logger LOG = LogManager.getLogger(PDFontFactory.class);
private static final String FONT_TYPE1C = "Type1C";
private static final String FONT_OPEN_TYPE = "OTTO";
private static final String FONT_TTF_COLLECTION = "ttcf";
private static final String FONT_TRUE_TYPE = "true";
private static final byte[] TTF_HEADER = new byte[] { 0, 1, 0, 0 };
private PDFontFactory()
{
}
/**
* Creates a new PDFont instance with the appropriate subclass.
*
* @param dictionary a font dictionary
* @return a PDFont instance, based on the SubType entry of the dictionary
* @throws IOException if something goes wrong
*/
public static PDFont createFont(COSDictionary dictionary) throws IOException
{
return createFont(dictionary, null);
}
private static class FontType
{
private static final List<String> cidType0Types //
= Arrays.asList(COSName.TYPE1.getName(), FONT_TYPE1C);
private static final List<String> cidType2Types //
= Arrays.asList(COSName.TRUE_TYPE.getName(), COSName.OPEN_TYPE.getName());
private final COSName type;
private final COSName subtype;
FontType(COSName type, String subtypeString)
{
this.type = type;
if (cidType0Types.contains(subtypeString))
{
subtype = COSName.CID_FONT_TYPE0;
}
else if (cidType2Types.contains(subtypeString))
{
subtype = COSName.CID_FONT_TYPE2;
}
else
{
subtype = null;
}
}
FontType(COSName type, COSName subtype)
{
this.type = type;
this.subtype = subtype;
}
FontType(COSName type)
{
this(type, (COSName) null);
}
public COSName getSubtype()
{
return subtype;
}
public boolean isCIDSubtype(COSName cidSubtype)
{
if (!COSName.TYPE0.equals(type))
{
return false;
}
return subtype != null && subtype.equals(cidSubtype);
}
}
/**
* Creates a new PDFont instance with the appropriate subclass.
*
* @param dictionary a font dictionary
* @param resourceCache resource cache, only useful for type 3 fonts, can be null
* @return a PDFont instance, based on the SubType entry of the dictionary
* @throws IOException if something goes wrong
*/
public static PDFont createFont(COSDictionary dictionary, ResourceCache resourceCache) throws IOException
{
COSName type = dictionary.getCOSName(COSName.TYPE, COSName.FONT);
if (!COSName.FONT.equals(type))
{
LOG.error("Expected 'Font' dictionary but found '{}'", type.getName());
}
COSName subType = dictionary.getCOSName(COSName.SUBTYPE);
if (COSName.TYPE1.equals(subType))
{
COSDictionary fd = dictionary.getCOSDictionary(COSName.FONT_DESC);
if (fd != null && fd.containsKey(COSName.FONT_FILE3))
{
return new PDType1CFont(dictionary);
}
return new PDType1Font(dictionary);
}
else if (COSName.MM_TYPE1.equals(subType))
{
COSDictionary fd = dictionary.getCOSDictionary(COSName.FONT_DESC);
if (fd != null && fd.containsKey(COSName.FONT_FILE3))
{
return new PDType1CFont(dictionary);
}
return new PDMMType1Font(dictionary);
}
else if (COSName.TRUE_TYPE.equals(subType))
{
return new PDTrueTypeFont(dictionary);
}
else if (COSName.TYPE3.equals(subType))
{
return new PDType3Font(dictionary, resourceCache);
}
else if (COSName.TYPE0.equals(subType))
{
COSDictionary fontDescriptor = getFontDescriptor(dictionary);
FontType fontTypeFromFont = getFontTypeFromFont(fontDescriptor, subType);
if (fontTypeFromFont != null)
{
COSDictionary descendantFont = getDescendantFont(dictionary);
COSName descFontType = descendantFont != null
? descendantFont.getCOSName(COSName.SUBTYPE) : null;
if (descFontType != null && !fontTypeFromFont.isCIDSubtype(descFontType))
{
fixType0Subtype(descendantFont, fontDescriptor, fontTypeFromFont.getSubtype());
}
}
return new PDType0Font(dictionary);
}
else if (COSName.CID_FONT_TYPE0.equals(subType))
{
throw new IOException("Type 0 descendant font not allowed");
}
else if (COSName.CID_FONT_TYPE2.equals(subType))
{
throw new IOException("Type 2 descendant font not allowed");
}
else
{
// assuming Type 1 font (see PDFBOX-1988) because it seems that Adobe Reader does this
// however, we may need more sophisticated logic perhaps looking at the FontFile
LOG.warn("Invalid font subtype '{}'", subType);
return new PDType1Font(dictionary);
}
}
private static void fixType0Subtype(COSDictionary descendantFont, COSDictionary fontDescriptor,
COSName newSubType)
{
LOG.warn("Try to fix different descendant font types for font {}",
fontDescriptor.getNameAsString(COSName.FONT_NAME));
if (COSName.CID_FONT_TYPE0.equals(newSubType)
&& !fontDescriptor.containsKey(COSName.FONT_FILE3)
&& fontDescriptor.containsKey(COSName.FONT_FILE2))
{
fontDescriptor.setItem(COSName.FONT_FILE3, fontDescriptor.getItem(COSName.FONT_FILE2));
fontDescriptor.removeItem(COSName.FONT_FILE2);
}
if (COSName.CID_FONT_TYPE2.equals(newSubType)
&& fontDescriptor.containsKey(COSName.FONT_FILE3)
&& !fontDescriptor.containsKey(COSName.FONT_FILE2))
{
fontDescriptor.setItem(COSName.FONT_FILE2, fontDescriptor.getItem(COSName.FONT_FILE3));
fontDescriptor.removeItem(COSName.FONT_FILE3);
}
descendantFont.setItem(COSName.SUBTYPE, newSubType);
}
private static FontType getFontTypeFromFont(COSDictionary fontDescriptor, COSName fontType)
throws IOException
{
byte[] fontHeader = getFontHeader(fontDescriptor);
if (fontHeader == null)
{
return null;
}
boolean isComposite = COSName.TYPE0.equals(fontType);
if (isTrueTypeFile(fontHeader) || isTrueTypeCollectionFile(fontHeader))
{
return isComposite //
? new FontType(COSName.TYPE0, COSName.TRUE_TYPE.getName())
: new FontType(COSName.TRUE_TYPE);
}
if (isOpenTypeFile(fontHeader))
{
return isComposite //
? new FontType(COSName.TYPE0, COSName.OPEN_TYPE.getName())
: new FontType(COSName.OPEN_TYPE);
}
if (isType1File(fontHeader) || isPfbFile(fontHeader))
{
if (isComposite)
{
return new FontType(COSName.TYPE0, COSName.TYPE1.getName());
}
return fontType.equals(COSName.MM_TYPE1)
? new FontType(COSName.MM_TYPE1, COSName.TYPE1.getName())
: new FontType(COSName.TYPE1);
}
// CFF fonts have a more or less variable header so that the check should be done
// after all others to avoid wrong classifications
if (isCFFFile(fontHeader))
{
if (isComposite)
{
return new FontType(COSName.TYPE0, FONT_TYPE1C);
}
return fontType.equals(COSName.MM_TYPE1) //
? new FontType(COSName.MM_TYPE1, FONT_TYPE1C)
: new FontType(COSName.TYPE1, FONT_TYPE1C);
}
return null;
}
private static boolean isTrueTypeFile(byte[] header)
{
return Arrays.equals(TTF_HEADER, header)
|| FONT_TRUE_TYPE.equals(new String(header, StandardCharsets.US_ASCII));
}
private static boolean isTrueTypeCollectionFile(byte[] header)
{
return FONT_TTF_COLLECTION.equals(new String(header, StandardCharsets.US_ASCII));
}
private static boolean isOpenTypeFile(byte[] header)
{
return FONT_OPEN_TYPE.equals(new String(header, StandardCharsets.US_ASCII));
}
private static boolean isType1File(byte[] header)
{
// All Type1 font programs must begin with the comment '%!' (0x25 + 0x21).
return header[0] == 0x25 && header[1] == 0x21;
}
private static boolean isPfbFile(byte[] header)
{
// all PFB fonts start with 0x80 followed by either 0x01 or 0x02
return header[0] == (byte) 0x80 && (header[1] == 0x01 || header[1] == 0x02);
}
private static boolean isCFFFile(byte[] header)
{
// the header consist of 4 values
// major version, minor version, header size, offset size
// the major version must be >= 1 and the offset size >= 1 and <= 4
return header[0] >= 1 && header[3] >= 1 && header[3] <= 4;
}
private static COSDictionary getFontDescriptor(COSDictionary dictionary)
{
COSDictionary fontDescriptor = dictionary.getCOSDictionary(COSName.FONT_DESC);
if (fontDescriptor == null)
{
COSDictionary descendantFont = getDescendantFont(dictionary);
if (descendantFont != null)
{
fontDescriptor = descendantFont.getCOSDictionary(COSName.FONT_DESC);
}
}
return fontDescriptor;
}
private static COSDictionary getDescendantFont(COSDictionary dictionary)
{
COSArray descendantFonts = dictionary.getCOSArray(COSName.DESCENDANT_FONTS);
if (descendantFonts != null && !descendantFonts.isEmpty())
{
COSBase descendantFontDictBase = descendantFonts.getObject(0);
if (descendantFontDictBase instanceof COSDictionary)
{
return (COSDictionary) descendantFontDictBase;
}
}
return null;
}
private static byte[] getFontHeader(COSDictionary fontDescriptor) throws IOException
{
if (fontDescriptor == null)
{
return null;
}
COSStream fontFile = fontDescriptor.getCOSStream(COSName.FONT_FILE);
if (fontFile == null)
{
fontFile = fontDescriptor.getCOSStream(COSName.FONT_FILE2);
}
if (fontFile == null)
{
fontFile = fontDescriptor.getCOSStream(COSName.FONT_FILE3);
}
byte[] header = null;
if (fontFile != null)
{
try (RandomAccessRead fontView = fontFile.createView())
{
int headerLength = 4;
header = new byte[headerLength];
int remainingBytes = headerLength;
int amountRead;
while ((amountRead = fontView.read(header, headerLength - remainingBytes,
remainingBytes)) > 0)
{
remainingBytes -= amountRead;
}
}
catch (IOException ex)
{
LOG.error(ex.getMessage(), ex);
}
}
return header;
}
/**
* Creates a new PDCIDFont instance with the appropriate subclass.
*
* @param dictionary descendant font dictionary
* @return a PDCIDFont instance, based on the SubType entry of the dictionary
* @throws IOException if something goes wrong
*/
static PDCIDFont createDescendantFont(COSDictionary dictionary, PDType0Font parent)
throws IOException
{
COSName type = dictionary.getCOSName(COSName.TYPE, COSName.FONT);
if (!COSName.FONT.equals(type))
{
throw new IOException("Expected 'Font' dictionary but found '" + type.getName() + "'");
}
COSName subType = dictionary.getCOSName(COSName.SUBTYPE);
if (COSName.CID_FONT_TYPE0.equals(subType))
{
return new PDCIDFontType0(dictionary, parent);
}
if (COSName.CID_FONT_TYPE2.equals(subType))
{
return new PDCIDFontType2(dictionary, parent);
}
throw new IOException("Invalid font type: " + type);
}
}