walkero
/
harfbuzz
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity
harfbuzz/src/hb-open-type.hh

898 lines
26 KiB
C++
Raw Blame History

/*
* Copyright © 2007,2008,2009,2010 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_TYPE_HH
#define HB_OPEN_TYPE_HH
#include "hb.hh"
#include "hb-blob.hh"
#include "hb-face.hh"
#include "hb-machinery.hh"
#include "hb-subset.hh"
namespace OT {
/*
*
* The OpenType Font File: Data Types
*/
/* "The following data types are used in the OpenType font file.
* All OpenType fonts use Motorola-style byte ordering (Big Endian):" */
/*
* Int types
*/
/* Integer types in big-endian order and no alignment requirement */
template <typename Type, unsigned int Size>
struct IntType
{
typedef Type type;
inline void set (Type i) { v.set (i); }
inline operator Type (void) const { return v; }
inline bool operator == (const IntType<Type,Size> &o) const { return (Type) v == (Type) o.v; }
inline bool operator != (const IntType<Type,Size> &o) const { return !(*this == o); }
static inline int cmp (const IntType<Type,Size> *a, const IntType<Type,Size> *b) { return b->cmp (*a); }
template <typename Type2>
inline int cmp (Type2 a) const
{
Type b = v;
if (sizeof (Type) < sizeof (int) && sizeof (Type2) < sizeof (int))
return (int) a - (int) b;
else
return a < b ? -1 : a == b ? 0 : +1;
}
inline bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (likely (c->check_struct (this)));
}
protected:
BEInt<Type, Size> v;
public:
DEFINE_SIZE_STATIC (Size);
};
typedef IntType<uint8_t, 1> HBUINT8; /* 8-bit unsigned integer. */
typedef IntType<int8_t, 1> HBINT8; /* 8-bit signed integer. */
typedef IntType<uint16_t, 2> HBUINT16; /* 16-bit unsigned integer. */
typedef IntType<int16_t, 2> HBINT16; /* 16-bit signed integer. */
typedef IntType<uint32_t, 4> HBUINT32; /* 32-bit unsigned integer. */
typedef IntType<int32_t, 4> HBINT32; /* 32-bit signed integer. */
typedef IntType<uint32_t, 3> HBUINT24; /* 24-bit unsigned integer. */
/* 16-bit signed integer (HBINT16) that describes a quantity in FUnits. */
typedef HBINT16 FWORD;
/* 32-bit signed integer (HBINT32) that describes a quantity in FUnits. */
typedef HBINT32 FWORD32;
/* 16-bit unsigned integer (HBUINT16) that describes a quantity in FUnits. */
typedef HBUINT16 UFWORD;
/* 16-bit signed fixed number with the low 14 bits of fraction (2.14). */
struct F2DOT14 : HBINT16
{
// 16384 means 1<<14
inline float to_float (void) const { return ((int32_t) v) / 16384.f; }
inline void set_float (float f) { v.set (round (f * 16384.f)); }
public:
DEFINE_SIZE_STATIC (2);
};
/* 32-bit signed fixed-point number (16.16). */
struct Fixed : HBINT32
{
// 65536 means 1<<16
inline float to_float (void) const { return ((int32_t) v) / 65536.f; }
inline void set_float (float f) { v.set (round (f * 65536.f)); }
public:
DEFINE_SIZE_STATIC (4);
};
/* Date represented in number of seconds since 12:00 midnight, January 1,
* 1904. The value is represented as a signed 64-bit integer. */
struct LONGDATETIME
{
inline bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (likely (c->check_struct (this)));
}
protected:
HBINT32 major;
HBUINT32 minor;
public:
DEFINE_SIZE_STATIC (8);
};
/* Array of four uint8s (length = 32 bits) used to identify a script, language
* system, feature, or baseline */
struct Tag : HBUINT32
{
/* What the char* converters return is NOT nul-terminated. Print using "%.4s" */
inline operator const char* (void) const { return reinterpret_cast<const char *> (&this->v); }
inline operator char* (void) { return reinterpret_cast<char *> (&this->v); }
public:
DEFINE_SIZE_STATIC (4);
};
/* Glyph index number, same as uint16 (length = 16 bits) */
typedef HBUINT16 GlyphID;
/* Script/language-system/feature index */
struct Index : HBUINT16 {
enum { NOT_FOUND_INDEX = 0xFFFFu };
};
DECLARE_NULL_NAMESPACE_BYTES (OT, Index);
typedef Index NameID;
/* Offset, Null offset = 0 */
template <typename Type, bool has_null=true>
struct Offset : Type
{
typedef Type type;
inline bool is_null (void) const { return has_null && 0 == *this; }
inline void *serialize (hb_serialize_context_t *c, const void *base)
{
void *t = c->start_embed<void> ();
this->set ((char *) t - (char *) base); /* TODO(serialize) Overflow? */
return t;
}
public:
DEFINE_SIZE_STATIC (sizeof (Type));
};
typedef Offset<HBUINT16> Offset16;
typedef Offset<HBUINT32> Offset32;
/* CheckSum */
struct CheckSum : HBUINT32
{
/* This is reference implementation from the spec. */
static inline uint32_t CalcTableChecksum (const HBUINT32 *Table, uint32_t Length)
{
uint32_t Sum = 0L;
assert (0 == (Length & 3));
const HBUINT32 *EndPtr = Table + Length / HBUINT32::static_size;
while (Table < EndPtr)
Sum += *Table++;
return Sum;
}
/* Note: data should be 4byte aligned and have 4byte padding at the end. */
inline void set_for_data (const void *data, unsigned int length)
{ set (CalcTableChecksum ((const HBUINT32 *) data, length)); }
public:
DEFINE_SIZE_STATIC (4);
};
/*
* Version Numbers
*/
template <typename FixedType=HBUINT16>
struct FixedVersion
{
inline uint32_t to_int (void) const { return (major << (sizeof (FixedType) * 8)) + minor; }
inline bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (c->check_struct (this));
}
FixedType major;
FixedType minor;
public:
DEFINE_SIZE_STATIC (2 * sizeof (FixedType));
};
/*
* Template subclasses of Offset that do the dereferencing.
* Use: (base+offset)
*/
template <typename Type, typename OffsetType=HBUINT16, bool has_null=true>
struct OffsetTo : Offset<OffsetType, has_null>
{
inline const Type& operator () (const void *base) const
{
if (unlikely (this->is_null ())) return Null (Type);
return StructAtOffset<const Type> (base, *this);
}
inline Type& operator () (void *base) const
{
if (unlikely (this->is_null ())) return Crap (Type);
return StructAtOffset<Type> (base, *this);
}
inline Type& serialize (hb_serialize_context_t *c, const void *base)
{
return * (Type *) Offset<OffsetType>::serialize (c, base);
}
template <typename T>
inline void serialize_subset (hb_subset_context_t *c, const T &src, const void *base)
{
if (&src == &Null (T))
{
this->set (0);
return;
}
serialize (c->serializer, base);
if (!src.subset (c))
this->set (0);
}
inline bool sanitize_shallow (hb_sanitize_context_t *c, const void *base) const
{
TRACE_SANITIZE (this);
if (unlikely (!c->check_struct (this))) return_trace (false);
if (unlikely (this->is_null ())) return_trace (true);
if (unlikely (!c->check_range (base, *this))) return_trace (false);
return_trace (true);
}
inline bool sanitize (hb_sanitize_context_t *c, const void *base) const
{
TRACE_SANITIZE (this);
return_trace (sanitize_shallow (c, base) &&
(this->is_null () ||
StructAtOffset<Type> (base, *this).sanitize (c) ||
neuter (c)));
}
template <typename T1>
inline bool sanitize (hb_sanitize_context_t *c, const void *base, T1 d1) const
{
TRACE_SANITIZE (this);
return_trace (sanitize_shallow (c, base) &&
(this->is_null () ||
StructAtOffset<Type> (base, *this).sanitize (c, d1) ||
neuter (c)));
}
template <typename T1, typename T2>
inline bool sanitize (hb_sanitize_context_t *c, const void *base, T1 d1, T2 d2) const
{
TRACE_SANITIZE (this);
return_trace (sanitize_shallow (c, base) &&
(this->is_null () ||
StructAtOffset<Type> (base, *this).sanitize (c, d1, d2) ||
neuter (c)));
}
template <typename T1, typename T2, typename T3>
inline bool sanitize (hb_sanitize_context_t *c, const void *base, T1 d1, T2 d2, T3 d3) const
{
TRACE_SANITIZE (this);
return_trace (sanitize_shallow (c, base) &&
(this->is_null () ||
StructAtOffset<Type> (base, *this).sanitize (c, d1, d2, d3) ||
neuter (c)));
}
/* Set the offset to Null */
inline bool neuter (hb_sanitize_context_t *c) const
{
if (!has_null) return false;
return c->try_set (this, 0);
}
DEFINE_SIZE_STATIC (sizeof (OffsetType));
};
template <typename Type, bool has_null=true> struct LOffsetTo : OffsetTo<Type, HBUINT32, has_null> {};
template <typename Base, typename OffsetType, bool has_null, typename Type>
static inline const Type& operator + (const Base &base, const OffsetTo<Type, OffsetType, has_null> &offset) { return offset (base); }
template <typename Base, typename OffsetType, bool has_null, typename Type>
static inline Type& operator + (Base &base, OffsetTo<Type, OffsetType, has_null> &offset) { return offset (base); }
/*
* Array Types
*/
template <typename Type>
struct UnsizedArrayOf
{
enum { item_size = Type::static_size };
HB_NO_CREATE_COPY_ASSIGN_TEMPLATE (UnsizedArrayOf, Type);
inline const Type& operator [] (unsigned int i) const
{
const Type *p = &arrayZ[i];
if (unlikely (p < arrayZ)) return Null (Type); /* Overflowed. */
return *p;
}
inline Type& operator [] (unsigned int i)
{
Type *p = &arrayZ[i];
if (unlikely (p < arrayZ)) return Crap (Type); /* Overflowed. */
return *p;
}
template <typename T> inline operator T * (void) { return arrayZ; }
template <typename T> inline operator const T * (void) const { return arrayZ; }
inline unsigned int get_size (unsigned int len) const
{ return len * Type::static_size; }
inline hb_array_t<Type> as_array (unsigned int len) { return hb_array_t<Type> (arrayZ, len); }
inline hb_array_t<const Type> as_array (unsigned int len) const { return hb_array_t<const Type> (arrayZ, len); }
inline bool sanitize (hb_sanitize_context_t *c, unsigned int count) const
{
TRACE_SANITIZE (this);
if (unlikely (!sanitize_shallow (c, count))) return_trace (false);
/* Note: for structs that do not reference other structs,
* we do not need to call their sanitize() as we already did
* a bound check on the aggregate array size. We just include
* a small unreachable expression to make sure the structs
* pointed to do have a simple sanitize(), ie. they do not
* reference other structs via offsets.
*/
(void) (false && arrayZ[0].sanitize (c));
return_trace (true);
}
inline bool sanitize (hb_sanitize_context_t *c, unsigned int count, const void *base) const
{
TRACE_SANITIZE (this);
if (unlikely (!sanitize_shallow (c, count))) return_trace (false);
for (unsigned int i = 0; i < count; i++)
if (unlikely (!arrayZ[i].sanitize (c, base)))
return_trace (false);
return_trace (true);
}
template <typename T>
inline bool sanitize (hb_sanitize_context_t *c, unsigned int count, const void *base, T user_data) const
{
TRACE_SANITIZE (this);
if (unlikely (!sanitize_shallow (c, count))) return_trace (false);
for (unsigned int i = 0; i < count; i++)
if (unlikely (!arrayZ[i].sanitize (c, base, user_data)))
return_trace (false);
return_trace (true);
}
inline bool sanitize_shallow (hb_sanitize_context_t *c, unsigned int count) const
{
TRACE_SANITIZE (this);
return_trace (c->check_array (arrayZ, count));
}
public:
Type arrayZ[VAR];
public:
DEFINE_SIZE_ARRAY (0, arrayZ);
};
/* Unsized array of offset's */
template <typename Type, typename OffsetType, bool has_null=true>
struct UnsizedOffsetArrayOf : UnsizedArrayOf<OffsetTo<Type, OffsetType, has_null> > {};
/* Unsized array of offsets relative to the beginning of the array itself. */
template <typename Type, typename OffsetType, bool has_null=true>
struct UnsizedOffsetListOf : UnsizedOffsetArrayOf<Type, OffsetType, has_null>
{
inline const Type& operator [] (unsigned int i) const
{
return this+this->arrayZ[i];
}
inline bool sanitize (hb_sanitize_context_t *c, unsigned int count) const
{
TRACE_SANITIZE (this);
return_trace ((UnsizedOffsetArrayOf<Type, OffsetType, has_null>::sanitize (c, count, this)));
}
template <typename T>
inline bool sanitize (hb_sanitize_context_t *c, unsigned int count, T user_data) const
{
TRACE_SANITIZE (this);
return_trace ((UnsizedOffsetArrayOf<Type, OffsetType, has_null>::sanitize (c, count, this, user_data)));
}
};
/* An array with a number of elements. */
template <typename Type, typename LenType=HBUINT16>
struct ArrayOf
{
enum { item_size = Type::static_size };
HB_NO_CREATE_COPY_ASSIGN_TEMPLATE2 (ArrayOf, Type, LenType);
inline const Type *sub_array (unsigned int start_offset, unsigned int *pcount /* IN/OUT */) const
{
unsigned int count = len;
if (unlikely (start_offset > count))
count = 0;
else
count -= start_offset;
count = MIN (count, *pcount);
*pcount = count;
return arrayZ + start_offset;
}
inline const Type& operator [] (unsigned int i) const
{
if (unlikely (i >= len)) return Null (Type);
return arrayZ[i];
}
inline Type& operator [] (unsigned int i)
{
if (unlikely (i >= len)) return Crap (Type);
return arrayZ[i];
}
inline unsigned int get_size (void) const
{ return len.static_size + len * Type::static_size; }
inline bool serialize (hb_serialize_context_t *c,
unsigned int items_len)
{
TRACE_SERIALIZE (this);
if (unlikely (!c->extend_min (*this))) return_trace (false);
len.set (items_len); /* TODO(serialize) Overflow? */
if (unlikely (!c->extend (*this))) return_trace (false);
return_trace (true);
}
inline bool serialize (hb_serialize_context_t *c,
Supplier<Type> &items,
unsigned int items_len)
{
TRACE_SERIALIZE (this);
if (unlikely (!serialize (c, items_len))) return_trace (false);
for (unsigned int i = 0; i < items_len; i++)
arrayZ[i] = items[i];
items += items_len;
return_trace (true);
}
inline bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
if (unlikely (!sanitize_shallow (c))) return_trace (false);
/* Note: for structs that do not reference other structs,
* we do not need to call their sanitize() as we already did
* a bound check on the aggregate array size. We just include
* a small unreachable expression to make sure the structs
* pointed to do have a simple sanitize(), ie. they do not
* reference other structs via offsets.
*/
(void) (false && arrayZ[0].sanitize (c));
return_trace (true);
}
inline bool sanitize (hb_sanitize_context_t *c, const void *base) const
{
TRACE_SANITIZE (this);
if (unlikely (!sanitize_shallow (c))) return_trace (false);
unsigned int count = len;
for (unsigned int i = 0; i < count; i++)
if (unlikely (!arrayZ[i].sanitize (c, base)))
return_trace (false);
return_trace (true);
}
template <typename T>
inline bool sanitize (hb_sanitize_context_t *c, const void *base, T user_data) const
{
TRACE_SANITIZE (this);
if (unlikely (!sanitize_shallow (c))) return_trace (false);
unsigned int count = len;
for (unsigned int i = 0; i < count; i++)
if (unlikely (!arrayZ[i].sanitize (c, base, user_data)))
return_trace (false);
return_trace (true);
}
template <typename SearchType>
inline int lsearch (const SearchType &x) const
{
unsigned int count = len;
for (unsigned int i = 0; i < count; i++)
if (!this->arrayZ[i].cmp (x))
return i;
return -1;
}
inline void qsort (void)
{
::qsort (arrayZ, len, sizeof (Type), Type::cmp);
}
inline bool sanitize_shallow (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (len.sanitize (c) && c->check_array (arrayZ, len));
}
public:
LenType len;
Type arrayZ[VAR];
public:
DEFINE_SIZE_ARRAY (sizeof (LenType), arrayZ);
};
template <typename Type> struct LArrayOf : ArrayOf<Type, HBUINT32> {};
typedef ArrayOf<HBUINT8, HBUINT8> PString;
/* Array of Offset's */
template <typename Type>
struct OffsetArrayOf : ArrayOf<OffsetTo<Type, HBUINT16> > {};
template <typename Type>
struct LOffsetArrayOf : ArrayOf<OffsetTo<Type, HBUINT32> > {};
template <typename Type>
struct LOffsetLArrayOf : ArrayOf<OffsetTo<Type, HBUINT32>, HBUINT32> {};
/* Array of offsets relative to the beginning of the array itself. */
template <typename Type>
struct OffsetListOf : OffsetArrayOf<Type>
{
inline const Type& operator [] (unsigned int i) const
{
if (unlikely (i >= this->len)) return Null (Type);
return this+this->arrayZ[i];
}
inline const Type& operator [] (unsigned int i)
{
if (unlikely (i >= this->len)) return Crap (Type);
return this+this->arrayZ[i];
}
inline bool subset (hb_subset_context_t *c) const
{
TRACE_SUBSET (this);
struct OffsetListOf<Type> *out = c->serializer->embed (*this);
if (unlikely (!out)) return_trace (false);
unsigned int count = this->len;
for (unsigned int i = 0; i < count; i++)
out->arrayZ[i].serialize_subset (c, (*this)[i], out);
return_trace (true);
}
inline bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (OffsetArrayOf<Type>::sanitize (c, this));
}
template <typename T>
inline bool sanitize (hb_sanitize_context_t *c, T user_data) const
{
TRACE_SANITIZE (this);
return_trace (OffsetArrayOf<Type>::sanitize (c, this, user_data));
}
};
/* An array starting at second element. */
template <typename Type, typename LenType=HBUINT16>
struct HeadlessArrayOf
{
enum { item_size = Type::static_size };
HB_NO_CREATE_COPY_ASSIGN_TEMPLATE2 (HeadlessArrayOf, Type, LenType);
inline const Type& operator [] (unsigned int i) const
{
if (unlikely (i >= lenP1 || !i)) return Null (Type);
return arrayZ[i-1];
}
inline Type& operator [] (unsigned int i)
{
if (unlikely (i >= lenP1 || !i)) return Crap (Type);
return arrayZ[i-1];
}
inline unsigned int get_size (void) const
{ return lenP1.static_size + (lenP1 ? lenP1 - 1 : 0) * Type::static_size; }
inline bool serialize (hb_serialize_context_t *c,
Supplier<Type> &items,
unsigned int items_len)
{
TRACE_SERIALIZE (this);
if (unlikely (!c->extend_min (*this))) return_trace (false);
lenP1.set (items_len); /* TODO(serialize) Overflow? */
if (unlikely (!items_len)) return_trace (true);
if (unlikely (!c->extend (*this))) return_trace (false);
for (unsigned int i = 0; i < items_len - 1; i++)
arrayZ[i] = items[i];
items += items_len - 1;
return_trace (true);
}
inline bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
if (unlikely (!sanitize_shallow (c))) return_trace (false);
/* Note: for structs that do not reference other structs,
* we do not need to call their sanitize() as we already did
* a bound check on the aggregate array size. We just include
* a small unreachable expression to make sure the structs
* pointed to do have a simple sanitize(), ie. they do not
* reference other structs via offsets.
*/
(void) (false && arrayZ[0].sanitize (c));
return_trace (true);
}
private:
inline bool sanitize_shallow (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (lenP1.sanitize (c) &&
(!lenP1 || c->check_array (arrayZ, lenP1 - 1)));
}
public:
LenType lenP1;
Type arrayZ[VAR];
public:
DEFINE_SIZE_ARRAY (sizeof (LenType), arrayZ);
};
/* An array storing length-1. */
template <typename Type, typename LenType=HBUINT16>
struct ArrayOfM1
{
HB_NO_CREATE_COPY_ASSIGN_TEMPLATE2 (ArrayOfM1, Type, LenType);
inline const Type& operator [] (unsigned int i) const
{
if (unlikely (i > lenM1)) return Null (Type);
return arrayZ[i];
}
inline Type& operator [] (unsigned int i)
{
if (unlikely (i > lenM1)) return Crap (Type);
return arrayZ[i];
}
inline unsigned int get_size (void) const
{ return lenM1.static_size + (lenM1 + 1) * Type::static_size; }
template <typename T>
inline bool sanitize (hb_sanitize_context_t *c, const void *base, T user_data) const
{
TRACE_SANITIZE (this);
if (unlikely (!sanitize_shallow (c))) return_trace (false);
unsigned int count = lenM1 + 1;
for (unsigned int i = 0; i < count; i++)
if (unlikely (!arrayZ[i].sanitize (c, base, user_data)))
return_trace (false);
return_trace (true);
}
private:
inline bool sanitize_shallow (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (lenM1.sanitize (c) &&
(c->check_array (arrayZ, lenM1 + 1)));
}
public:
LenType lenM1;
Type arrayZ[VAR];
public:
DEFINE_SIZE_ARRAY (sizeof (LenType), arrayZ);
};
/* An array with sorted elements. Supports binary searching. */
template <typename Type, typename LenType=HBUINT16>
struct SortedArrayOf : ArrayOf<Type, LenType>
{
template <typename SearchType>
inline int bsearch (const SearchType &x) const
{
/* Hand-coded bsearch here since this is in the hot inner loop. */
const Type *arr = this->arrayZ;
int min = 0, max = (int) this->len - 1;
while (min <= max)
{
int mid = ((unsigned int) min + (unsigned int) max) / 2;
int c = arr[mid].cmp (x);
if (c < 0) max = mid - 1;
else if (c > 0) min = mid + 1;
else return mid;
}
return -1;
}
};
/*
* Binary-search arrays
*/
template <typename LenType=HBUINT16>
struct BinSearchHeader
{
inline operator uint32_t (void) const { return len; }
inline bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (c->check_struct (this));
}
inline void set (unsigned int v)
{
len.set (v);
assert (len == v);
entrySelector.set (MAX (1u, hb_bit_storage (v)) - 1);
searchRange.set (16 * (1u << entrySelector));
rangeShift.set (v * 16 > searchRange
? 16 * v - searchRange
: 0);
}
protected:
LenType len;
LenType searchRange;
LenType entrySelector;
LenType rangeShift;
public:
DEFINE_SIZE_STATIC (8);
};
template <typename Type, typename LenType=HBUINT16>
struct BinSearchArrayOf : SortedArrayOf<Type, BinSearchHeader<LenType> > {};
struct VarSizedBinSearchHeader
{
inline bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (c->check_struct (this));
}
HBUINT16 unitSize; /* Size of a lookup unit for this search in bytes. */
HBUINT16 nUnits; /* Number of units of the preceding size to be searched. */
HBUINT16 searchRange; /* The value of unitSize times the largest power of 2
* that is less than or equal to the value of nUnits. */
HBUINT16 entrySelector; /* The log base 2 of the largest power of 2 less than
* or equal to the value of nUnits. */
HBUINT16 rangeShift; /* The value of unitSize times the difference of the
* value of nUnits minus the largest power of 2 less
* than or equal to the value of nUnits. */
public:
DEFINE_SIZE_STATIC (10);
};
template <typename Type>
struct VarSizedBinSearchArrayOf
{
enum { item_size = Type::static_size };
HB_NO_CREATE_COPY_ASSIGN_TEMPLATE (VarSizedBinSearchArrayOf, Type);
inline const Type& operator [] (unsigned int i) const
{
if (unlikely (i >= header.nUnits)) return Null (Type);
return StructAtOffset<Type> (&bytesZ, i * header.unitSize);
}
inline Type& operator [] (unsigned int i)
{
return StructAtOffset<Type> (&bytesZ, i * header.unitSize);
}
inline unsigned int get_size (void) const
{ return header.static_size + header.nUnits * header.unitSize; }
inline bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
if (unlikely (!sanitize_shallow (c))) return_trace (false);
/* Note: for structs that do not reference other structs,
* we do not need to call their sanitize() as we already did
* a bound check on the aggregate array size. We just include
* a small unreachable expression to make sure the structs
* pointed to do have a simple sanitize(), ie. they do not
* reference other structs via offsets.
*/
(void) (false && StructAtOffset<Type> (&bytesZ, 0).sanitize (c));
return_trace (true);
}
inline bool sanitize (hb_sanitize_context_t *c, const void *base) const
{
TRACE_SANITIZE (this);
if (unlikely (!sanitize_shallow (c))) return_trace (false);
unsigned int count = header.nUnits;
for (unsigned int i = 0; i < count; i++)
if (unlikely (!(*this)[i].sanitize (c, base)))
return_trace (false);
return_trace (true);
}
template <typename T>
inline bool sanitize (hb_sanitize_context_t *c, const void *base, T user_data) const
{
TRACE_SANITIZE (this);
if (unlikely (!sanitize_shallow (c))) return_trace (false);
unsigned int count = header.nUnits;
for (unsigned int i = 0; i < count; i++)
if (unlikely (!(*this)[i].sanitize (c, base, user_data)))
return_trace (false);
return_trace (true);
}
template <typename T>
inline const Type *bsearch (const T &key) const
{
unsigned int size = header.unitSize;
int min = 0, max = (int) header.nUnits - 1;
while (min <= max)
{
int mid = ((unsigned int) min + (unsigned int) max) / 2;
const Type *p = (const Type *) (((const char *) &bytesZ) + (mid * size));
int c = p->cmp (key);
if (c < 0) max = mid - 1;
else if (c > 0) min = mid + 1;
else return p;
}
return nullptr;
}
private:
inline bool sanitize_shallow (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (header.sanitize (c) &&
Type::static_size <= header.unitSize &&
c->check_range (bytesZ.arrayZ,
header.nUnits,
header.unitSize));
}
protected:
VarSizedBinSearchHeader header;
UnsizedArrayOf<HBUINT8> bytesZ;
public:
DEFINE_SIZE_ARRAY (10, bytesZ);
};
} /* namespace OT */
#endif /* HB_OPEN_TYPE_HH */
Reference in New Issue View Git Blame Copy Permalink