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 /*

  * Copyright © 2007,2008,2009  Red Hat, Inc.

  * Copyright © 2012  Google, Inc.

  *

  *  This is part of HarfBuzz, a text shaping library.

  *

  * Permission is hereby granted, without written agreement and without

  * license or royalty fees, to use, copy, modify, and distribute this

  * software and its documentation for any purpose, provided that the

  * above copyright notice and the following two paragraphs appear in

  * all copies of this software.

  *

  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR

  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES

  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN

  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH

  * DAMAGE.

  *

  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,

  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND

  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS

  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO

  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.

  *

  * Red Hat Author(s): Behdad Esfahbod

  * Google Author(s): Behdad Esfahbod

  */

 #ifndef HB_OPEN_FILE_PRIVATE_HH

 #define HB_OPEN_FILE_PRIVATE_HH

 #include "hb-open-type-private.hh"

 namespace OT {

 /*

  *

  * The OpenType Font File

  *

  */

 /*

  * Organization of an OpenType Font

  */

 struct OpenTypeFontFile;

 struct OffsetTable;

 struct TTCHeader;

 typedef struct TableRecord

 {

   inline bool sanitize (hb_sanitize_context_t *c) {

     TRACE_SANITIZE (this);

     return TRACE_RETURN (c->check_struct (this));

   }

   Tag		tag;		/* 4-byte identifier. */

   CheckSum	checkSum;	/* CheckSum for this table. */

   ULONG		offset;		/* Offset from beginning of TrueType font

 				 * file. */

   ULONG		length;		/* Length of this table. */

   public:

   DEFINE_SIZE_STATIC (16);

 } OpenTypeTable;

 typedef struct OffsetTable

 {

   friend struct OpenTypeFontFile;

   inline unsigned int get_table_count (void) const

   { return numTables; }

   inline const TableRecord& get_table (unsigned int i) const

   {

     if (unlikely (i >= numTables)) return Null(TableRecord);

     return tables[i];

   }

   inline bool find_table_index (hb_tag_t tag, unsigned int *table_index) const

   {

     Tag t;

     t.set (tag);

     unsigned int count = numTables;

     for (unsigned int i = 0; i < count; i++)

     {

       if (t == tables[i].tag)

       {

         if (table_index) *table_index = i;

         return true;

       }

     }

     if (table_index) *table_index = Index::NOT_FOUND_INDEX;

     return false;

   }

   inline const TableRecord& get_table_by_tag (hb_tag_t tag) const

   {

     unsigned int table_index;

     find_table_index (tag, &table_index);

     return get_table (table_index);

   }

   public:

   inline bool sanitize (hb_sanitize_context_t *c) {

     TRACE_SANITIZE (this);

     return TRACE_RETURN (c->check_struct (this) && c->check_array (tables, TableRecord::static_size, numTables));

   }

   protected:

   Tag		sfnt_version;	/* '\0\001\0\00' if TrueType / 'OTTO' if CFF */

   USHORT	numTables;	/* Number of tables. */

   USHORT	searchRange;	/* (Maximum power of 2 <= numTables) x 16 */

   USHORT	entrySelector;	/* Log2(maximum power of 2 <= numTables). */

   USHORT	rangeShift;	/* NumTables x 16-searchRange. */

   TableRecord	tables[VAR];	/* TableRecord entries. numTables items */

   public:

   DEFINE_SIZE_ARRAY (12, tables);

 } OpenTypeFontFace;

 /*

  * TrueType Collections

  */

 struct TTCHeaderVersion1

 {

   friend struct TTCHeader;

   inline unsigned int get_face_count (void) const { return table.len; }

   inline const OpenTypeFontFace& get_face (unsigned int i) const { return this+table[i]; }

   inline bool sanitize (hb_sanitize_context_t *c) {

     TRACE_SANITIZE (this);

     return TRACE_RETURN (table.sanitize (c, this));

   }

   protected:

   Tag		ttcTag;		/* TrueType Collection ID string: 'ttcf' */

   FixedVersion	version;	/* Version of the TTC Header (1.0),

 				 * 0x00010000 */

   LongOffsetLongArrayOf<OffsetTable>

 		table;		/* Array of offsets to the OffsetTable for each font

 				 * from the beginning of the file */

   public:

   DEFINE_SIZE_ARRAY (12, table);

 };

 struct TTCHeader

 {

   friend struct OpenTypeFontFile;

   private:

   inline unsigned int get_face_count (void) const

   {

     switch (u.header.version.major) {

     case 2: /* version 2 is compatible with version 1 */

     case 1: return u.version1.get_face_count ();

     default:return 0;

     }

   }

   inline const OpenTypeFontFace& get_face (unsigned int i) const

   {

     switch (u.header.version.major) {

     case 2: /* version 2 is compatible with version 1 */

     case 1: return u.version1.get_face (i);

     default:return Null(OpenTypeFontFace);

     }

   }

   inline bool sanitize (hb_sanitize_context_t *c) {

     TRACE_SANITIZE (this);

     if (unlikely (!u.header.version.sanitize (c))) return TRACE_RETURN (false);

     switch (u.header.version.major) {

     case 2: /* version 2 is compatible with version 1 */

     case 1: return TRACE_RETURN (u.version1.sanitize (c));

     default:return TRACE_RETURN (true);

     }

   }

   protected:

   union {

   struct {

   Tag		ttcTag;		/* TrueType Collection ID string: 'ttcf' */

   FixedVersion	version;	/* Version of the TTC Header (1.0 or 2.0),

 				 * 0x00010000 or 0x00020000 */

   }			header;

   TTCHeaderVersion1	version1;

   } u;

 };

 /*

  * OpenType Font File

  */

 struct OpenTypeFontFile

 {

   static const hb_tag_t CFFTag		= HB_TAG ('O','T','T','O'); /* OpenType with Postscript outlines */

   static const hb_tag_t TrueTypeTag	= HB_TAG ( 0 , 1 , 0 , 0 ); /* OpenType with TrueType outlines */

   static const hb_tag_t TTCTag		= HB_TAG ('t','t','c','f'); /* TrueType Collection */

   static const hb_tag_t TrueTag		= HB_TAG ('t','r','u','e'); /* Obsolete Apple TrueType */

   static const hb_tag_t Typ1Tag		= HB_TAG ('t','y','p','1'); /* Obsolete Apple Type1 font in SFNT container */

   inline hb_tag_t get_tag (void) const { return u.tag; }

   inline unsigned int get_face_count (void) const

   {

     switch (u.tag) {

     case CFFTag:	/* All the non-collection tags */

     case TrueTag:

     case Typ1Tag:

     case TrueTypeTag:	return 1;

     case TTCTag:	return u.ttcHeader.get_face_count ();

     default:		return 0;

     }

   }

   inline const OpenTypeFontFace& get_face (unsigned int i) const

   {

     switch (u.tag) {

     /* Note: for non-collection SFNT data we ignore index.  This is because

      * Apple dfont container is a container of SFNT's.  So each SFNT is a

      * non-TTC, but the index is more than zero. */

     case CFFTag:	/* All the non-collection tags */

     case TrueTag:

     case Typ1Tag:

     case TrueTypeTag:	return u.fontFace;

     case TTCTag:	return u.ttcHeader.get_face (i);

     default:		return Null(OpenTypeFontFace);

     }

   }

   inline bool sanitize (hb_sanitize_context_t *c) {

     TRACE_SANITIZE (this);

     if (unlikely (!u.tag.sanitize (c))) return TRACE_RETURN (false);

     switch (u.tag) {

     case CFFTag:	/* All the non-collection tags */

     case TrueTag:

     case Typ1Tag:

     case TrueTypeTag:	return TRACE_RETURN (u.fontFace.sanitize (c));

     case TTCTag:	return TRACE_RETURN (u.ttcHeader.sanitize (c));

     default:		return TRACE_RETURN (true);

     }

   }

   protected:

   union {

   Tag			tag;		/* 4-byte identifier. */

   OpenTypeFontFace	fontFace;

   TTCHeader		ttcHeader;

   } u;

   public:

   DEFINE_SIZE_UNION (4, tag);

 };

 } /* namespace OT */

 #endif /* HB_OPEN_FILE_PRIVATE_HH */