web/Zend/Pdf/Font.php
changeset 0 4eba9c11703f
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/web/Zend/Pdf/Font.php	Mon Dec 13 18:29:26 2010 +0100
@@ -0,0 +1,732 @@
+<?php
+/**
+ * Zend Framework
+ *
+ * LICENSE
+ *
+ * This source file is subject to the new BSD license that is bundled
+ * with this package in the file LICENSE.txt.
+ * It is also available through the world-wide-web at this URL:
+ * http://framework.zend.com/license/new-bsd
+ * If you did not receive a copy of the license and are unable to
+ * obtain it through the world-wide-web, please send an email
+ * to license@zend.com so we can send you a copy immediately.
+ *
+ * @category   Zend
+ * @package    Zend_Pdf
+ * @subpackage Fonts
+ * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license    http://framework.zend.com/license/new-bsd     New BSD License
+ * @version    $Id: Font.php 20211 2010-01-12 02:14:29Z yoshida@zend.co.jp $
+ */
+
+
+/**
+ * Abstract factory class which vends {@link Zend_Pdf_Resource_Font} objects.
+ *
+ * Font objects themselves are normally instantiated through the factory methods
+ * {@link fontWithName()} or {@link fontWithPath()}.
+ *
+ * This class is also the home for font-related constants because the name of
+ * the true base class ({@link Zend_Pdf_Resource_Font}) is not intuitive for the
+ * end user.
+ *
+ * @package    Zend_Pdf
+ * @subpackage Fonts
+ * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license    http://framework.zend.com/license/new-bsd     New BSD License
+ */
+abstract class Zend_Pdf_Font
+{
+  /**** Class Constants ****/
+
+
+  /* Font Types */
+
+    /**
+     * Unknown font type.
+     */
+    const TYPE_UNKNOWN = 0;
+
+    /**
+     * One of the standard 14 PDF fonts.
+     */
+    const TYPE_STANDARD = 1;
+
+    /**
+     * A PostScript Type 1 font.
+     */
+    const TYPE_TYPE_1 = 2;
+
+    /**
+     * A TrueType font or an OpenType font containing TrueType outlines.
+     */
+    const TYPE_TRUETYPE = 3;
+
+    /**
+     * Type 0 composite font.
+     */
+    const TYPE_TYPE_0 = 4;
+
+    /**
+     * CID font containing a PostScript Type 1 font.
+     * These fonts are used only to construct Type 0 composite fonts and can't be used directly
+     */
+    const TYPE_CIDFONT_TYPE_0 = 5;
+
+    /**
+     * CID font containing a TrueType font or an OpenType font containing TrueType outlines.
+     * These fonts are used only to construct Type 0 composite fonts and can't be used directly
+     */
+    const TYPE_CIDFONT_TYPE_2 = 6;
+
+
+  /* Names of the Standard 14 PDF Fonts */
+
+    /**
+     * Name of the standard PDF font Courier.
+     */
+    const FONT_COURIER = 'Courier';
+
+    /**
+     * Name of the bold style of the standard PDF font Courier.
+     */
+    const FONT_COURIER_BOLD = 'Courier-Bold';
+
+    /**
+     * Name of the italic style of the standard PDF font Courier.
+     */
+    const FONT_COURIER_OBLIQUE = 'Courier-Oblique';
+
+    /**
+     * Convenience constant for a common misspelling of
+     * {@link FONT_COURIER_OBLIQUE}.
+     */
+    const FONT_COURIER_ITALIC = 'Courier-Oblique';
+
+    /**
+     * Name of the bold and italic style of the standard PDF font Courier.
+     */
+    const FONT_COURIER_BOLD_OBLIQUE = 'Courier-BoldOblique';
+
+    /**
+     * Convenience constant for a common misspelling of
+     * {@link FONT_COURIER_BOLD_OBLIQUE}.
+     */
+    const FONT_COURIER_BOLD_ITALIC = 'Courier-BoldOblique';
+
+    /**
+     * Name of the standard PDF font Helvetica.
+     */
+    const FONT_HELVETICA = 'Helvetica';
+
+    /**
+     * Name of the bold style of the standard PDF font Helvetica.
+     */
+    const FONT_HELVETICA_BOLD = 'Helvetica-Bold';
+
+    /**
+     * Name of the italic style of the standard PDF font Helvetica.
+     */
+    const FONT_HELVETICA_OBLIQUE = 'Helvetica-Oblique';
+
+    /**
+     * Convenience constant for a common misspelling of
+     * {@link FONT_HELVETICA_OBLIQUE}.
+     */
+    const FONT_HELVETICA_ITALIC = 'Helvetica-Oblique';
+
+    /**
+     * Name of the bold and italic style of the standard PDF font Helvetica.
+     */
+    const FONT_HELVETICA_BOLD_OBLIQUE = 'Helvetica-BoldOblique';
+
+    /**
+     * Convenience constant for a common misspelling of
+     * {@link FONT_HELVETICA_BOLD_OBLIQUE}.
+     */
+    const FONT_HELVETICA_BOLD_ITALIC = 'Helvetica-BoldOblique';
+
+    /**
+     * Name of the standard PDF font Symbol.
+     */
+    const FONT_SYMBOL = 'Symbol';
+
+    /**
+     * Name of the standard PDF font Times.
+     */
+    const FONT_TIMES_ROMAN = 'Times-Roman';
+
+    /**
+     * Convenience constant for a common misspelling of
+     * {@link FONT_TIMES_ROMAN}.
+     */
+    const FONT_TIMES = 'Times-Roman';
+
+    /**
+     * Name of the bold style of the standard PDF font Times.
+     */
+    const FONT_TIMES_BOLD = 'Times-Bold';
+
+    /**
+     * Name of the italic style of the standard PDF font Times.
+     */
+    const FONT_TIMES_ITALIC = 'Times-Italic';
+
+    /**
+     * Name of the bold and italic style of the standard PDF font Times.
+     */
+    const FONT_TIMES_BOLD_ITALIC = 'Times-BoldItalic';
+
+    /**
+     * Name of the standard PDF font Zapf Dingbats.
+     */
+    const FONT_ZAPFDINGBATS = 'ZapfDingbats';
+
+
+  /* Font Name String Types */
+
+    /**
+     * Full copyright notice for the font.
+     */
+    const NAME_COPYRIGHT =  0;
+
+    /**
+     * Font family name. Used to group similar styles of fonts together.
+     */
+    const NAME_FAMILY =  1;
+
+    /**
+     * Font style within the font family. Examples: Regular, Italic, Bold, etc.
+     */
+    const NAME_STYLE =  2;
+
+    /**
+     * Unique font identifier.
+     */
+    const NAME_ID =  3;
+
+    /**
+     * Full font name. Usually a combination of the {@link NAME_FAMILY} and
+     * {@link NAME_STYLE} strings.
+     */
+    const NAME_FULL =  4;
+
+    /**
+     * Version number of the font.
+     */
+    const NAME_VERSION =  5;
+
+    /**
+     * PostScript name for the font. This is the name used to identify fonts
+     * internally and within the PDF file.
+     */
+    const NAME_POSTSCRIPT =  6;
+
+    /**
+     * Font trademark notice. This is distinct from the {@link NAME_COPYRIGHT}.
+     */
+    const NAME_TRADEMARK =  7;
+
+    /**
+     * Name of the font manufacturer.
+     */
+    const NAME_MANUFACTURER =  8;
+
+    /**
+     * Name of the designer of the font.
+     */
+    const NAME_DESIGNER =  9;
+
+    /**
+     * Description of the font. May contain revision information, usage
+     * recommendations, features, etc.
+     */
+    const NAME_DESCRIPTION = 10;
+
+    /**
+     * URL of the font vendor. Some fonts may contain a unique serial number
+     * embedded in this URL, which is used for licensing.
+     */
+    const NAME_VENDOR_URL = 11;
+
+    /**
+     * URL of the font designer ({@link NAME_DESIGNER}).
+     */
+    const NAME_DESIGNER_URL = 12;
+
+    /**
+     * Plain language licensing terms for the font.
+     */
+    const NAME_LICENSE = 13;
+
+    /**
+     * URL of more detailed licensing information for the font.
+     */
+    const NAME_LICENSE_URL = 14;
+
+    /**
+     * Preferred font family. Used by some fonts to work around a Microsoft
+     * Windows limitation where only four fonts styles can share the same
+     * {@link NAME_FAMILY} value.
+     */
+    const NAME_PREFERRED_FAMILY = 16;
+
+    /**
+     * Preferred font style. A more descriptive string than {@link NAME_STYLE}.
+     */
+    const NAME_PREFERRED_STYLE = 17;
+
+    /**
+     * Suggested text to use as a representative sample of the font.
+     */
+    const NAME_SAMPLE_TEXT = 19;
+
+    /**
+     * PostScript CID findfont name.
+     */
+    const NAME_CID_NAME = 20;
+
+
+  /* Font Weights */
+
+    /**
+     * Thin font weight.
+     */
+    const WEIGHT_THIN = 100;
+
+    /**
+     * Extra-light (Ultra-light) font weight.
+     */
+    const WEIGHT_EXTRA_LIGHT = 200;
+
+    /**
+     * Light font weight.
+     */
+    const WEIGHT_LIGHT = 300;
+
+    /**
+     * Normal (Regular) font weight.
+     */
+    const WEIGHT_NORMAL = 400;
+
+    /**
+     * Medium font weight.
+     */
+    const WEIGHT_MEDIUM = 500;
+
+    /**
+     * Semi-bold (Demi-bold) font weight.
+     */
+    const WEIGHT_SEMI_BOLD = 600;
+
+    /**
+     * Bold font weight.
+     */
+    const WEIGHT_BOLD = 700;
+
+    /**
+     * Extra-bold (Ultra-bold) font weight.
+     */
+    const WEIGHT_EXTRA_BOLD = 800;
+
+    /**
+     * Black (Heavy) font weight.
+     */
+    const WEIGHT_BLACK = 900;
+
+
+  /* Font Widths */
+
+    /**
+     * Ultra-condensed font width. Typically 50% of normal.
+     */
+    const WIDTH_ULTRA_CONDENSED = 1;
+
+    /**
+     * Extra-condensed font width. Typically 62.5% of normal.
+     */
+    const WIDTH_EXTRA_CONDENSED = 2;
+
+    /**
+     * Condensed font width. Typically 75% of normal.
+     */
+    const WIDTH_CONDENSED = 3;
+
+    /**
+     * Semi-condensed font width. Typically 87.5% of normal.
+     */
+    const WIDTH_SEMI_CONDENSED = 4;
+
+    /**
+     * Normal (Medium) font width.
+     */
+    const WIDTH_NORMAL = 5;
+
+    /**
+     * Semi-expanded font width. Typically 112.5% of normal.
+     */
+    const WIDTH_SEMI_EXPANDED = 6;
+
+    /**
+     * Expanded font width. Typically 125% of normal.
+     */
+    const WIDTH_EXPANDED = 7;
+
+    /**
+     * Extra-expanded font width. Typically 150% of normal.
+     */
+    const WIDTH_EXTRA_EXPANDED = 8;
+
+    /**
+     * Ultra-expanded font width. Typically 200% of normal.
+     */
+    const WIDTH_ULTRA_EXPANDED = 9;
+
+
+  /* Font Embedding Options */
+
+    /**
+     * Do not embed the font in the PDF document.
+     */
+    const EMBED_DONT_EMBED = 0x01;
+
+    /**
+     * Embed, but do not subset the font in the PDF document.
+     */
+    const EMBED_DONT_SUBSET = 0x02;
+
+    /**
+     * Embed, but do not compress the font in the PDF document.
+     */
+    const EMBED_DONT_COMPRESS = 0x04;
+
+    /**
+     * Suppress the exception normally thrown if the font cannot be embedded
+     * due to its copyright bits being set.
+     */
+    const EMBED_SUPPRESS_EMBED_EXCEPTION = 0x08;
+
+
+
+  /**** Class Variables ****/
+
+
+    /**
+     * Array whose keys are the unique PostScript names of instantiated fonts.
+     * The values are the font objects themselves.
+     * @var array
+     */
+    private static $_fontNames = array();
+
+    /**
+     * Array whose keys are the md5 hash of the full paths on disk for parsed
+     * fonts. The values are the font objects themselves.
+     * @var array
+     */
+    private static $_fontFilePaths = array();
+
+
+
+  /**** Public Interface ****/
+
+
+  /* Factory Methods */
+
+    /**
+     * Returns a {@link Zend_Pdf_Resource_Font} object by full name.
+     *
+     * This is the preferred method to obtain one of the standard 14 PDF fonts.
+     *
+     * The result of this method is cached, preventing unnecessary duplication
+     * of font objects. Repetitive calls for a font with the same name will
+     * return the same object.
+     *
+     * The $embeddingOptions parameter allows you to set certain flags related
+     * to font embedding. You may combine options by OR-ing them together. See
+     * the EMBED_ constants defined in {@link Zend_Pdf_Font} for the list of
+     * available options and their descriptions. Note that this value is only
+     * used when creating a font for the first time. If a font with the same
+     * name already exists, you will get that object and the options you specify
+     * here will be ignored. This is because fonts are only embedded within the
+     * PDF file once.
+     *
+     * If the font name supplied does not match the name of a previously
+     * instantiated object and it is not one of the 14 standard PDF fonts, an
+     * exception will be thrown.
+     *
+     * @param string $name Full PostScript name of font.
+     * @param integer $embeddingOptions (optional) Options for font embedding.
+     * @return Zend_Pdf_Resource_Font
+     * @throws Zend_Pdf_Exception
+     */
+    public static function fontWithName($name, $embeddingOptions = 0)
+        {
+        /* First check the cache. Don't duplicate font objects.
+         */
+        if (isset(Zend_Pdf_Font::$_fontNames[$name])) {
+            return Zend_Pdf_Font::$_fontNames[$name];
+        }
+
+        /**
+         * @todo It would be cool to be able to have a mapping of font names to
+         *   file paths in a configuration file for frequently used custom
+         *   fonts. This would allow a user to use custom fonts without having
+         *   to hard-code file paths all over the place. Table this idea until
+         *   {@link Zend_Config} is ready.
+         */
+
+        /* Not an existing font and no mapping in the config file. Check to see
+         * if this is one of the standard 14 PDF fonts.
+         */
+        switch ($name) {
+            case Zend_Pdf_Font::FONT_COURIER:
+                require_once 'Zend/Pdf/Resource/Font/Simple/Standard/Courier.php';
+                $font = new Zend_Pdf_Resource_Font_Simple_Standard_Courier();
+                break;
+
+            case Zend_Pdf_Font::FONT_COURIER_BOLD:
+                require_once 'Zend/Pdf/Resource/Font/Simple/Standard/CourierBold.php';
+                $font = new Zend_Pdf_Resource_Font_Simple_Standard_CourierBold();
+                break;
+
+            case Zend_Pdf_Font::FONT_COURIER_OBLIQUE:
+                require_once 'Zend/Pdf/Resource/Font/Simple/Standard/CourierOblique.php';
+                $font = new Zend_Pdf_Resource_Font_Simple_Standard_CourierOblique();
+                break;
+
+            case Zend_Pdf_Font::FONT_COURIER_BOLD_OBLIQUE:
+                require_once 'Zend/Pdf/Resource/Font/Simple/Standard/CourierBoldOblique.php';
+                $font = new Zend_Pdf_Resource_Font_Simple_Standard_CourierBoldOblique();
+                break;
+
+            case Zend_Pdf_Font::FONT_HELVETICA:
+                require_once 'Zend/Pdf/Resource/Font/Simple/Standard/Helvetica.php';
+                $font = new Zend_Pdf_Resource_Font_Simple_Standard_Helvetica();
+                break;
+
+            case Zend_Pdf_Font::FONT_HELVETICA_BOLD:
+                require_once 'Zend/Pdf/Resource/Font/Simple/Standard/HelveticaBold.php';
+                $font = new Zend_Pdf_Resource_Font_Simple_Standard_HelveticaBold();
+                break;
+
+            case Zend_Pdf_Font::FONT_HELVETICA_OBLIQUE:
+                require_once 'Zend/Pdf/Resource/Font/Simple/Standard/HelveticaOblique.php';
+                $font = new Zend_Pdf_Resource_Font_Simple_Standard_HelveticaOblique();
+                break;
+
+            case Zend_Pdf_Font::FONT_HELVETICA_BOLD_OBLIQUE:
+                require_once 'Zend/Pdf/Resource/Font/Simple/Standard/HelveticaBoldOblique.php';
+                $font = new Zend_Pdf_Resource_Font_Simple_Standard_HelveticaBoldOblique();
+                break;
+
+            case Zend_Pdf_Font::FONT_SYMBOL:
+                require_once 'Zend/Pdf/Resource/Font/Simple/Standard/Symbol.php';
+                $font = new Zend_Pdf_Resource_Font_Simple_Standard_Symbol();
+                break;
+
+            case Zend_Pdf_Font::FONT_TIMES_ROMAN:
+                require_once 'Zend/Pdf/Resource/Font/Simple/Standard/TimesRoman.php';
+                $font = new Zend_Pdf_Resource_Font_Simple_Standard_TimesRoman();
+                break;
+
+            case Zend_Pdf_Font::FONT_TIMES_BOLD:
+                require_once 'Zend/Pdf/Resource/Font/Simple/Standard/TimesBold.php';
+                $font = new Zend_Pdf_Resource_Font_Simple_Standard_TimesBold();
+                break;
+
+            case Zend_Pdf_Font::FONT_TIMES_ITALIC:
+                require_once 'Zend/Pdf/Resource/Font/Simple/Standard/TimesItalic.php';
+                $font = new Zend_Pdf_Resource_Font_Simple_Standard_TimesItalic();
+                break;
+
+            case Zend_Pdf_Font::FONT_TIMES_BOLD_ITALIC:
+                require_once 'Zend/Pdf/Resource/Font/Simple/Standard/TimesBoldItalic.php';
+                $font = new Zend_Pdf_Resource_Font_Simple_Standard_TimesBoldItalic();
+                break;
+
+            case Zend_Pdf_Font::FONT_ZAPFDINGBATS:
+                require_once 'Zend/Pdf/Resource/Font/Simple/Standard/ZapfDingbats.php';
+                $font = new Zend_Pdf_Resource_Font_Simple_Standard_ZapfDingbats();
+                break;
+
+            default:
+                require_once 'Zend/Pdf/Exception.php';
+                throw new Zend_Pdf_Exception("Unknown font name: $name",
+                                             Zend_Pdf_Exception::BAD_FONT_NAME);
+        }
+
+        /* Add this new font to the cache array and return it for use.
+         */
+        Zend_Pdf_Font::$_fontNames[$name] = $font;
+        return $font;
+    }
+
+    /**
+     * Returns a {@link Zend_Pdf_Resource_Font} object by file path.
+     *
+     * The result of this method is cached, preventing unnecessary duplication
+     * of font objects. Repetitive calls for the font with the same path will
+     * return the same object.
+     *
+     * The $embeddingOptions parameter allows you to set certain flags related
+     * to font embedding. You may combine options by OR-ing them together. See
+     * the EMBED_ constants defined in {@link Zend_Pdf_Font} for the list of
+     * available options and their descriptions. Note that this value is only
+     * used when creating a font for the first time. If a font with the same
+     * name already exists, you will get that object and the options you specify
+     * here will be ignored. This is because fonts are only embedded within the
+     * PDF file once.
+     *
+     * If the file path supplied does not match the path of a previously
+     * instantiated object or the font type cannot be determined, an exception
+     * will be thrown.
+     *
+     * @param string $filePath Full path to the font file.
+     * @param integer $embeddingOptions (optional) Options for font embedding.
+     * @return Zend_Pdf_Resource_Font
+     * @throws Zend_Pdf_Exception
+     */
+    public static function fontWithPath($filePath, $embeddingOptions = 0)
+    {
+        /* First check the cache. Don't duplicate font objects.
+         */
+        $filePathKey = md5($filePath);
+        if (isset(Zend_Pdf_Font::$_fontFilePaths[$filePathKey])) {
+            return Zend_Pdf_Font::$_fontFilePaths[$filePathKey];
+        }
+
+        /* Create a file parser data source object for this file. File path and
+         * access permission checks are handled here.
+         */
+        require_once 'Zend/Pdf/FileParserDataSource/File.php';
+        $dataSource = new Zend_Pdf_FileParserDataSource_File($filePath);
+
+        /* Attempt to determine the type of font. We can't always trust file
+         * extensions, but try that first since it's fastest.
+         */
+        $fileExtension = strtolower(pathinfo($filePath, PATHINFO_EXTENSION));
+
+        /* If it turns out that the file is named improperly and we guess the
+         * wrong type, we'll get null instead of a font object.
+         */
+        switch ($fileExtension) {
+            case 'ttf':
+                $font = Zend_Pdf_Font::_extractTrueTypeFont($dataSource, $embeddingOptions);
+                break;
+
+            default:
+                /* Unrecognized extension. Try to determine the type by actually
+                 * parsing it below.
+                 */
+                $font = null;
+                break;
+        }
+
+
+        if ($font === null) {
+            /* There was no match for the file extension or the extension was
+             * wrong. Attempt to detect the type of font by actually parsing it.
+             * We'll do the checks in order of most likely format to try to
+             * reduce the detection time.
+             */
+
+            // OpenType
+
+            // TrueType
+            if (($font === null) && ($fileExtension != 'ttf')) {
+                $font = Zend_Pdf_Font::_extractTrueTypeFont($dataSource, $embeddingOptions);
+            }
+
+            // Type 1 PostScript
+
+            // Mac OS X dfont
+
+            // others?
+        }
+
+
+        /* Done with the data source object.
+         */
+        $dataSource = null;
+
+        if ($font !== null) {
+            /* Parsing was successful. Add this font instance to the cache arrays
+             * and return it for use.
+             */
+            $fontName = $font->getFontName(Zend_Pdf_Font::NAME_POSTSCRIPT, '', '');
+            Zend_Pdf_Font::$_fontNames[$fontName] = $font;
+            $filePathKey = md5($filePath);
+            Zend_Pdf_Font::$_fontFilePaths[$filePathKey] = $font;
+            return $font;
+
+        } else {
+            /* The type of font could not be determined. Give up.
+             */
+            require_once 'Zend/Pdf/Exception.php';
+            throw new Zend_Pdf_Exception("Cannot determine font type: $filePath",
+                                         Zend_Pdf_Exception::CANT_DETERMINE_FONT_TYPE);
+         }
+
+    }
+
+
+
+  /**** Internal Methods ****/
+
+
+  /* Font Extraction Methods */
+
+    /**
+     * Attempts to extract a TrueType font from the data source.
+     *
+     * If the font parser throws an exception that suggests the data source
+     * simply doesn't contain a TrueType font, catches it and returns null. If
+     * an exception is thrown that suggests the TrueType font is corrupt or
+     * otherwise unusable, throws that exception. If successful, returns the
+     * font object.
+     *
+     * @param Zend_Pdf_FileParserDataSource $dataSource
+     * @param integer $embeddingOptions Options for font embedding.
+     * @return Zend_Pdf_Resource_Font_OpenType_TrueType May also return null if
+     *   the data source does not appear to contain a TrueType font.
+     * @throws Zend_Pdf_Exception
+     */
+    protected static function _extractTrueTypeFont($dataSource, $embeddingOptions)
+    {
+        try {
+            require_once 'Zend/Pdf/FileParser/Font/OpenType/TrueType.php';
+            $fontParser = new Zend_Pdf_FileParser_Font_OpenType_TrueType($dataSource);
+
+            $fontParser->parse();
+            if ($fontParser->isAdobeLatinSubset) {
+                require_once 'Zend/Pdf/Resource/Font/Simple/Parsed/TrueType.php';
+                $font = new Zend_Pdf_Resource_Font_Simple_Parsed_TrueType($fontParser, $embeddingOptions);
+            } else {
+                require_once 'Zend/Pdf/Resource/Font/CidFont/TrueType.php';
+                require_once 'Zend/Pdf/Resource/Font/Type0.php';
+                /* Use Composite Type 0 font which supports Unicode character mapping */
+                $cidFont = new Zend_Pdf_Resource_Font_CidFont_TrueType($fontParser, $embeddingOptions);
+                $font    = new Zend_Pdf_Resource_Font_Type0($cidFont);
+            }
+        } catch (Zend_Pdf_Exception $e) {
+            /* The following exception codes suggest that this isn't really a
+             * TrueType font. If we caught such an exception, simply return
+             * null. For all other cases, it probably is a TrueType font but has
+             * a problem; throw the exception again.
+             */
+            $fontParser = null;
+            require_once 'Zend/Pdf/Exception.php';
+            switch ($e->getCode()) {
+                case Zend_Pdf_Exception::WRONG_FONT_TYPE:    // break intentionally omitted
+                case Zend_Pdf_Exception::BAD_TABLE_COUNT:    // break intentionally omitted
+                case Zend_Pdf_Exception::BAD_MAGIC_NUMBER:
+                    return null;
+
+                default:
+                    throw new Zend_Pdf_Exception($e->getMessage(), $e->getCode(), $e);
+            }
+        }
+        return $font;
+    }
+}