harfbuzz/src/hb-open-file.hh

527 lines
15 KiB
C++

/*
* 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_HH
#define HB_OPEN_FILE_HH
#include "hb-open-type.hh"
#include "hb-ot-head-table.hh"
namespace OT {
/*
*
* The OpenType Font File
*
*/
/*
* Organization of an OpenType Font
*/
struct OpenTypeFontFile;
struct OffsetTable;
struct TTCHeader;
typedef struct TableRecord
{
int cmp (Tag t) const { return -t.cmp (tag); }
HB_INTERNAL static int cmp (const void *pa, const void *pb)
{
const TableRecord *a = (const TableRecord *) pa;
const TableRecord *b = (const TableRecord *) pb;
return b->cmp (a->tag);
}
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (c->check_struct (this));
}
Tag tag; /* 4-byte identifier. */
CheckSum checkSum; /* CheckSum for this table. */
Offset32 offset; /* Offset from beginning of TrueType font
* file. */
HBUINT32 length; /* Length of this table. */
public:
DEFINE_SIZE_STATIC (16);
} OpenTypeTable;
typedef struct OffsetTable
{
friend struct OpenTypeFontFile;
unsigned int get_table_count () const { return tables.len; }
const TableRecord& get_table (unsigned int i) const
{ return tables[i]; }
unsigned int get_table_tags (unsigned int start_offset,
unsigned int *table_count, /* IN/OUT */
hb_tag_t *table_tags /* OUT */) const
{
if (table_count)
{
if (start_offset >= tables.len)
*table_count = 0;
else
*table_count = hb_min (*table_count, tables.len - start_offset);
const TableRecord *sub_tables = tables.arrayZ + start_offset;
unsigned int count = *table_count;
for (unsigned int i = 0; i < count; i++)
table_tags[i] = sub_tables[i].tag;
}
return tables.len;
}
bool find_table_index (hb_tag_t tag, unsigned int *table_index) const
{
Tag t;
t = tag;
return tables.bfind (t, table_index, HB_BFIND_NOT_FOUND_STORE, Index::NOT_FOUND_INDEX);
}
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:
template <typename item_t>
bool serialize (hb_serialize_context_t *c,
hb_tag_t sfnt_tag,
hb_array_t<item_t> items)
{
TRACE_SERIALIZE (this);
/* Alloc 12 for the OTHeader. */
if (unlikely (!c->extend_min (*this))) return_trace (false);
/* Write sfntVersion (bytes 0..3). */
sfnt_version = sfnt_tag;
/* Take space for numTables, searchRange, entrySelector, RangeShift
* and the TableRecords themselves. */
if (unlikely (!tables.serialize (c, items.length))) return_trace (false);
const char *dir_end = (const char *) c->head;
HBUINT32 *checksum_adjustment = nullptr;
/* Write OffsetTables, alloc for and write actual table blobs. */
for (unsigned int i = 0; i < tables.len; i++)
{
TableRecord &rec = tables.arrayZ[i];
hb_blob_t *blob = items[i].blob;
rec.tag = items[i].tag;
rec.length = blob->length;
rec.offset.serialize (c, this);
/* Allocate room for the table and copy it. */
char *start = (char *) c->allocate_size<void> (rec.length);
if (unlikely (!start)) return false;
if (likely (rec.length))
memcpy (start, blob->data, rec.length);
/* 4-byte alignment. */
c->align (4);
const char *end = (const char *) c->head;
if (items[i].tag == HB_OT_TAG_head &&
(unsigned) (end - start) >= head::static_size)
{
head *h = (head *) start;
checksum_adjustment = &h->checkSumAdjustment;
*checksum_adjustment = 0;
}
rec.checkSum.set_for_data (start, end - start);
}
tables.qsort ();
if (checksum_adjustment)
{
CheckSum checksum;
/* The following line is a slower version of the following block. */
//checksum.set_for_data (this, (const char *) c->head - (const char *) this);
checksum.set_for_data (this, dir_end - (const char *) this);
for (unsigned int i = 0; i < items.length; i++)
{
TableRecord &rec = tables.arrayZ[i];
checksum = checksum + rec.checkSum;
}
*checksum_adjustment = 0xB1B0AFBAu - checksum;
}
return_trace (true);
}
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (c->check_struct (this) && tables.sanitize (c));
}
protected:
Tag sfnt_version; /* '\0\001\0\00' if TrueType / 'OTTO' if CFF */
BinSearchArrayOf<TableRecord>
tables;
public:
DEFINE_SIZE_ARRAY (12, tables);
} OpenTypeFontFace;
/*
* TrueType Collections
*/
struct TTCHeaderVersion1
{
friend struct TTCHeader;
unsigned int get_face_count () const { return table.len; }
const OpenTypeFontFace& get_face (unsigned int i) const { return this+table[i]; }
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (table.sanitize (c, this));
}
protected:
Tag ttcTag; /* TrueType Collection ID string: 'ttcf' */
FixedVersion<>version; /* Version of the TTC Header (1.0),
* 0x00010000u */
LArrayOf<LOffsetTo<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:
unsigned int get_face_count () 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;
}
}
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);
}
}
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
if (unlikely (!u.header.version.sanitize (c))) return_trace (false);
switch (u.header.version.major) {
case 2: /* version 2 is compatible with version 1 */
case 1: return_trace (u.version1.sanitize (c));
default:return_trace (true);
}
}
protected:
union {
struct {
Tag ttcTag; /* TrueType Collection ID string: 'ttcf' */
FixedVersion<>version; /* Version of the TTC Header (1.0 or 2.0),
* 0x00010000u or 0x00020000u */
} header;
TTCHeaderVersion1 version1;
} u;
};
/*
* Mac Resource Fork
*
* http://mirror.informatimago.com/next/developer.apple.com/documentation/mac/MoreToolbox/MoreToolbox-99.html
*/
struct ResourceRecord
{
const OpenTypeFontFace & get_face (const void *data_base) const
{ return CastR<OpenTypeFontFace> ((data_base+offset).arrayZ); }
bool sanitize (hb_sanitize_context_t *c,
const void *data_base) const
{
TRACE_SANITIZE (this);
return_trace (c->check_struct (this) &&
offset.sanitize (c, data_base) &&
get_face (data_base).sanitize (c));
}
protected:
HBUINT16 id; /* Resource ID. */
HBINT16 nameOffset; /* Offset from beginning of resource name list
* to resource name, -1 means there is none. */
HBUINT8 attrs; /* Resource attributes */
NNOffsetTo<LArrayOf<HBUINT8>, HBUINT24>
offset; /* Offset from beginning of data block to
* data for this resource */
HBUINT32 reserved; /* Reserved for handle to resource */
public:
DEFINE_SIZE_STATIC (12);
};
#define HB_TAG_sfnt HB_TAG ('s','f','n','t')
struct ResourceTypeRecord
{
unsigned int get_resource_count () const
{ return tag == HB_TAG_sfnt ? resCountM1 + 1 : 0; }
bool is_sfnt () const { return tag == HB_TAG_sfnt; }
const ResourceRecord& get_resource_record (unsigned int i,
const void *type_base) const
{ return (type_base+resourcesZ).as_array (get_resource_count ())[i]; }
bool sanitize (hb_sanitize_context_t *c,
const void *type_base,
const void *data_base) const
{
TRACE_SANITIZE (this);
return_trace (c->check_struct (this) &&
resourcesZ.sanitize (c, type_base,
get_resource_count (),
data_base));
}
protected:
Tag tag; /* Resource type. */
HBUINT16 resCountM1; /* Number of resources minus 1. */
NNOffsetTo<UnsizedArrayOf<ResourceRecord>>
resourcesZ; /* Offset from beginning of resource type list
* to reference item list for this type. */
public:
DEFINE_SIZE_STATIC (8);
};
struct ResourceMap
{
unsigned int get_face_count () const
{
unsigned int count = get_type_count ();
for (unsigned int i = 0; i < count; i++)
{
const ResourceTypeRecord& type = get_type_record (i);
if (type.is_sfnt ())
return type.get_resource_count ();
}
return 0;
}
const OpenTypeFontFace& get_face (unsigned int idx,
const void *data_base) const
{
unsigned int count = get_type_count ();
for (unsigned int i = 0; i < count; i++)
{
const ResourceTypeRecord& type = get_type_record (i);
/* The check for idx < count is here because ResourceRecord is NOT null-safe.
* Because an offset of 0 there does NOT mean null. */
if (type.is_sfnt () && idx < type.get_resource_count ())
return type.get_resource_record (idx, &(this+typeList)).get_face (data_base);
}
return Null (OpenTypeFontFace);
}
bool sanitize (hb_sanitize_context_t *c, const void *data_base) const
{
TRACE_SANITIZE (this);
return_trace (c->check_struct (this) &&
typeList.sanitize (c, this,
&(this+typeList),
data_base));
}
private:
unsigned int get_type_count () const { return (this+typeList).lenM1 + 1; }
const ResourceTypeRecord& get_type_record (unsigned int i) const
{ return (this+typeList)[i]; }
protected:
HBUINT8 reserved0[16]; /* Reserved for copy of resource header */
HBUINT32 reserved1; /* Reserved for handle to next resource map */
HBUINT16 resreved2; /* Reserved for file reference number */
HBUINT16 attrs; /* Resource fork attribute */
NNOffsetTo<ArrayOfM1<ResourceTypeRecord>>
typeList; /* Offset from beginning of map to
* resource type list */
Offset16 nameList; /* Offset from beginning of map to
* resource name list */
public:
DEFINE_SIZE_STATIC (28);
};
struct ResourceForkHeader
{
unsigned int get_face_count () const
{ return (this+map).get_face_count (); }
const OpenTypeFontFace& get_face (unsigned int idx,
unsigned int *base_offset = nullptr) const
{
const OpenTypeFontFace &face = (this+map).get_face (idx, &(this+data));
if (base_offset)
*base_offset = (const char *) &face - (const char *) this;
return face;
}
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (c->check_struct (this) &&
data.sanitize (c, this, dataLen) &&
map.sanitize (c, this, &(this+data)));
}
protected:
LNNOffsetTo<UnsizedArrayOf<HBUINT8>>
data; /* Offset from beginning of resource fork
* to resource data */
LNNOffsetTo<ResourceMap >
map; /* Offset from beginning of resource fork
* to resource map */
HBUINT32 dataLen; /* Length of resource data */
HBUINT32 mapLen; /* Length of resource map */
public:
DEFINE_SIZE_STATIC (16);
};
/*
* OpenType Font File
*/
struct OpenTypeFontFile
{
enum {
CFFTag = HB_TAG ('O','T','T','O'), /* OpenType with Postscript outlines */
TrueTypeTag = HB_TAG ( 0 , 1 , 0 , 0 ), /* OpenType with TrueType outlines */
TTCTag = HB_TAG ('t','t','c','f'), /* TrueType Collection */
DFontTag = HB_TAG ( 0 , 0 , 1 , 0 ), /* DFont Mac Resource Fork */
TrueTag = HB_TAG ('t','r','u','e'), /* Obsolete Apple TrueType */
Typ1Tag = HB_TAG ('t','y','p','1') /* Obsolete Apple Type1 font in SFNT container */
};
hb_tag_t get_tag () const { return u.tag; }
unsigned int get_face_count () 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 ();
case DFontTag: return u.rfHeader.get_face_count ();
default: return 0;
}
}
const OpenTypeFontFace& get_face (unsigned int i, unsigned int *base_offset = nullptr) const
{
if (base_offset)
*base_offset = 0;
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);
case DFontTag: return u.rfHeader.get_face (i, base_offset);
default: return Null(OpenTypeFontFace);
}
}
template <typename item_t>
bool serialize_single (hb_serialize_context_t *c,
hb_tag_t sfnt_tag,
hb_array_t<item_t> items)
{
TRACE_SERIALIZE (this);
assert (sfnt_tag != TTCTag);
if (unlikely (!c->extend_min (*this))) return_trace (false);
return_trace (u.fontFace.serialize (c, sfnt_tag, items));
}
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
if (unlikely (!u.tag.sanitize (c))) return_trace (false);
switch (u.tag) {
case CFFTag: /* All the non-collection tags */
case TrueTag:
case Typ1Tag:
case TrueTypeTag: return_trace (u.fontFace.sanitize (c));
case TTCTag: return_trace (u.ttcHeader.sanitize (c));
case DFontTag: return_trace (u.rfHeader.sanitize (c));
default: return_trace (true);
}
}
protected:
union {
Tag tag; /* 4-byte identifier. */
OpenTypeFontFace fontFace;
TTCHeader ttcHeader;
ResourceForkHeader rfHeader;
} u;
public:
DEFINE_SIZE_UNION (4, tag);
};
} /* namespace OT */
#endif /* HB_OPEN_FILE_HH */