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/*
* 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_PRIVATE_HH
#define HB_OPEN_TYPE_PRIVATE_HH
#include "hb-private.hh"
namespace OT {
/*
* Casts
*/
/* Cast to struct T, reference to reference */
template<typename Type, typename TObject>
static inline const Type& CastR(const TObject &X)
{ return reinterpret_cast<const Type&> (X); }
template<typename Type, typename TObject>
static inline Type& CastR(TObject &X)
{ return reinterpret_cast<Type&> (X); }
/* Cast to struct T, pointer to pointer */
template<typename Type, typename TObject>
static inline const Type* CastP(const TObject *X)
{ return reinterpret_cast<const Type*> (X); }
template<typename Type, typename TObject>
static inline Type* CastP(TObject *X)
{ return reinterpret_cast<Type*> (X); }
/* StructAtOffset<T>(P,Ofs) returns the struct T& that is placed at memory
* location pointed to by P plus Ofs bytes. */
template<typename Type>
static inline const Type& StructAtOffset(const void *P, unsigned int offset)
{ return * reinterpret_cast<const Type*> ((const char *) P + offset); }
template<typename Type>
static inline Type& StructAtOffset(void *P, unsigned int offset)
{ return * reinterpret_cast<Type*> ((char *) P + offset); }
/* StructAfter<T>(X) returns the struct T& that is placed after X.
* Works with X of variable size also. X must implement get_size() */
template<typename Type, typename TObject>
static inline const Type& StructAfter(const TObject &X)
{ return StructAtOffset<Type>(&X, X.get_size()); }
template<typename Type, typename TObject>
static inline Type& StructAfter(TObject &X)
{ return StructAtOffset<Type>(&X, X.get_size()); }
/*
* Size checking
*/
/* Check _assertion in a method environment */
#define _DEFINE_INSTANCE_ASSERTION1(_line, _assertion) \
inline void _instance_assertion_on_line_##_line (void) const \
{ \
ASSERT_STATIC (_assertion); \
ASSERT_INSTANCE_POD (*this); /* Make sure it's POD. */ \
}
# define _DEFINE_INSTANCE_ASSERTION0(_line, _assertion) _DEFINE_INSTANCE_ASSERTION1 (_line, _assertion)
# define DEFINE_INSTANCE_ASSERTION(_assertion) _DEFINE_INSTANCE_ASSERTION0 (__LINE__, _assertion)
/* Check that _code compiles in a method environment */
#define _DEFINE_COMPILES_ASSERTION1(_line, _code) \
inline void _compiles_assertion_on_line_##_line (void) const \
{ _code; }
# define _DEFINE_COMPILES_ASSERTION0(_line, _code) _DEFINE_COMPILES_ASSERTION1 (_line, _code)
# define DEFINE_COMPILES_ASSERTION(_code) _DEFINE_COMPILES_ASSERTION0 (__LINE__, _code)
#define DEFINE_SIZE_STATIC(size) \
DEFINE_INSTANCE_ASSERTION (sizeof (*this) == (size)); \
static const unsigned int static_size = (size); \
static const unsigned int min_size = (size)
/* Size signifying variable-sized array */
#define VAR 1
#define DEFINE_SIZE_UNION(size, _member) \
DEFINE_INSTANCE_ASSERTION (this->u._member.static_size == (size)); \
static const unsigned int min_size = (size)
#define DEFINE_SIZE_MIN(size) \
DEFINE_INSTANCE_ASSERTION (sizeof (*this) >= (size)); \
static const unsigned int min_size = (size)
#define DEFINE_SIZE_ARRAY(size, array) \
DEFINE_INSTANCE_ASSERTION (sizeof (*this) == (size) + sizeof (array[0])); \
DEFINE_COMPILES_ASSERTION ((void) array[0].static_size) \
static const unsigned int min_size = (size)
#define DEFINE_SIZE_ARRAY2(size, array1, array2) \
DEFINE_INSTANCE_ASSERTION (sizeof (*this) == (size) + sizeof (this->array1[0]) + sizeof (this->array2[0])); \
DEFINE_COMPILES_ASSERTION ((void) array1[0].static_size; (void) array2[0].static_size) \
static const unsigned int min_size = (size)
/*
* Null objects
*/
/* Global nul-content Null pool. Enlarge as necessary. */
/* TODO This really should be a extern HB_INTERNAL and defined somewhere... */
static const void *_NullPool[(256+8) / sizeof (void *)];
/* Generic nul-content Null objects. */
template <typename Type>
static inline const Type& Null (void) {
ASSERT_STATIC (sizeof (Type) <= sizeof (_NullPool));
return *CastP<Type> (_NullPool);
}
/* Specializaiton for arbitrary-content arbitrary-sized Null objects. */
#define DEFINE_NULL_DATA(Type, data) \
static const char _Null##Type[sizeof (Type) + 1] = data; /* +1 is for nul-termination in data */ \
template <> \
/*static*/ inline const Type& Null<Type> (void) { \
return *CastP<Type> (_Null##Type); \
} /* The following line really exists such that we end in a place needing semicolon */ \
ASSERT_STATIC (Type::min_size + 1 <= sizeof (_Null##Type))
/* Accessor macro. */
#define Null(Type) Null<Type>()
/*
* Dispatch
*/
template <typename Context, typename Return, unsigned int MaxDebugDepth>
struct hb_dispatch_context_t
{
static const unsigned int max_debug_depth = MaxDebugDepth;
typedef Return return_t;
template <typename T, typename F>
inline bool may_dispatch (const T *obj, const F *format) { return true; }
static return_t no_dispatch_return_value (void) { return Context::default_return_value (); }
};
/*
* Sanitize
*/
#ifndef HB_DEBUG_SANITIZE
#define HB_DEBUG_SANITIZE (HB_DEBUG+0)
#endif
#define TRACE_SANITIZE(this) \
hb_auto_trace_t<HB_DEBUG_SANITIZE, bool> trace \
(&c->debug_depth, c->get_name (), this, HB_FUNC, \
"");
/* This limits sanitizing time on really broken fonts. */
#ifndef HB_SANITIZE_MAX_EDITS
#define HB_SANITIZE_MAX_EDITS 8
#endif
struct hb_sanitize_context_t :
hb_dispatch_context_t<hb_sanitize_context_t, bool, HB_DEBUG_SANITIZE>
{
inline hb_sanitize_context_t (void) :
debug_depth (0),
start (NULL), end (NULL),
writable (false), edit_count (0),
blob (NULL) {}
inline const char *get_name (void) { return "SANITIZE"; }
template <typename T, typename F>
inline bool may_dispatch (const T *obj, const F *format)
{ return format->sanitize (this); }
template <typename T>
inline return_t dispatch (const T &obj) { return obj.sanitize (this); }
static return_t default_return_value (void) { return true; }
static return_t no_dispatch_return_value (void) { return false; }
bool stop_sublookup_iteration (const return_t r) const { return !r; }
inline void init (hb_blob_t *b)
{
this->blob = hb_blob_reference (b);
this->writable = false;
}
inline void start_processing (void)
{
this->start = hb_blob_get_data (this->blob, NULL);
this->end = this->start + hb_blob_get_length (this->blob);
assert (this->start <= this->end); /* Must not overflow. */
this->edit_count = 0;
this->debug_depth = 0;
DEBUG_MSG_LEVEL (SANITIZE, start, 0, +1,
"start [%p..%p] (%lu bytes)",
this->start, this->end,
(unsigned long) (this->end - this->start));
}
inline void end_processing (void)
{
DEBUG_MSG_LEVEL (SANITIZE, this->start, 0, -1,
"end [%p..%p] %u edit requests",
this->start, this->end, this->edit_count);
hb_blob_destroy (this->blob);
this->blob = NULL;
this->start = this->end = NULL;
}
inline bool check_range (const void *base, unsigned int len) const
{
const char *p = (const char *) base;
bool ok = this->start <= p && p <= this->end && (unsigned int) (this->end - p) >= len;
DEBUG_MSG_LEVEL (SANITIZE, p, this->debug_depth+1, 0,
"check_range [%p..%p] (%d bytes) in [%p..%p] -> %s",
p, p + len, len,
this->start, this->end,
ok ? "OK" : "OUT-OF-RANGE");
return likely (ok);
}
inline bool check_array (const void *base, unsigned int record_size, unsigned int len) const
{
const char *p = (const char *) base;
bool overflows = _hb_unsigned_int_mul_overflows (len, record_size);
unsigned int array_size = record_size * len;
bool ok = !overflows && this->check_range (base, array_size);
DEBUG_MSG_LEVEL (SANITIZE, p, this->debug_depth+1, 0,
"check_array [%p..%p] (%d*%d=%d bytes) in [%p..%p] -> %s",
p, p + (record_size * len), record_size, len, (unsigned int) array_size,
this->start, this->end,
overflows ? "OVERFLOWS" : ok ? "OK" : "OUT-OF-RANGE");
return likely (ok);
}
template <typename Type>
inline bool check_struct (const Type *obj) const
{
return likely (this->check_range (obj, obj->min_size));
}
inline bool may_edit (const void *base HB_UNUSED, unsigned int len HB_UNUSED)
{
if (this->edit_count >= HB_SANITIZE_MAX_EDITS)
return false;
const char *p = (const char *) base;
this->edit_count++;
DEBUG_MSG_LEVEL (SANITIZE, p, this->debug_depth+1, 0,
"may_edit(%u) [%p..%p] (%d bytes) in [%p..%p] -> %s",
this->edit_count,
p, p + len, len,
this->start, this->end,
this->writable ? "GRANTED" : "DENIED");
return this->writable;
}
template <typename Type, typename ValueType>
inline bool try_set (const Type *obj, const ValueType &v) {
if (this->may_edit (obj, obj->static_size)) {
const_cast<Type *> (obj)->set (v);
return true;
}
return false;
}
mutable unsigned int debug_depth;
const char *start, *end;
bool writable;
unsigned int edit_count;
hb_blob_t *blob;
};
/* Template to sanitize an object. */
template <typename Type>
struct Sanitizer
{
static hb_blob_t *sanitize (hb_blob_t *blob) {
hb_sanitize_context_t c[1];
bool sane;
/* TODO is_sane() stuff */
c->init (blob);
retry:
DEBUG_MSG_FUNC (SANITIZE, c->start, "start");
c->start_processing ();
if (unlikely (!c->start)) {
c->end_processing ();
return blob;
}
Type *t = CastP<Type> (const_cast<char *> (c->start));
sane = t->sanitize (c);
if (sane) {
if (c->edit_count) {
DEBUG_MSG_FUNC (SANITIZE, c->start, "passed first round with %d edits; going for second round", c->edit_count);
/* sanitize again to ensure no toe-stepping */
c->edit_count = 0;
sane = t->sanitize (c);
if (c->edit_count) {
DEBUG_MSG_FUNC (SANITIZE, c->start, "requested %d edits in second round; FAILLING", c->edit_count);
sane = false;
}
}
} else {
unsigned int edit_count = c->edit_count;
if (edit_count && !c->writable) {
c->start = hb_blob_get_data_writable (blob, NULL);
c->end = c->start + hb_blob_get_length (blob);
if (c->start) {
c->writable = true;
/* ok, we made it writable by relocating. try again */
DEBUG_MSG_FUNC (SANITIZE, c->start, "retry");
goto retry;
}
}
}
c->end_processing ();
DEBUG_MSG_FUNC (SANITIZE, c->start, sane ? "PASSED" : "FAILED");
if (sane)
return blob;
else {
hb_blob_destroy (blob);
return hb_blob_get_empty ();
}
}
static const Type* lock_instance (hb_blob_t *blob) {
hb_blob_make_immutable (blob);
const char *base = hb_blob_get_data (blob, NULL);
return unlikely (!base) ? &Null(Type) : CastP<Type> (base);
}
};
/*
* Serialize
*/
#ifndef HB_DEBUG_SERIALIZE
#define HB_DEBUG_SERIALIZE (HB_DEBUG+0)
#endif
#define TRACE_SERIALIZE(this) \
hb_auto_trace_t<HB_DEBUG_SERIALIZE, bool> trace \
(&c->debug_depth, "SERIALIZE", c, HB_FUNC, \
"");
struct hb_serialize_context_t
{
inline hb_serialize_context_t (void *start_, unsigned int size)
{
this->start = (char *) start_;
this->end = this->start + size;
this->ran_out_of_room = false;
this->head = this->start;
this->debug_depth = 0;
}
template <typename Type>
inline Type *start_serialize (void)
{
DEBUG_MSG_LEVEL (SERIALIZE, this->start, 0, +1,
"start [%p..%p] (%lu bytes)",
this->start, this->end,
(unsigned long) (this->end - this->start));
return start_embed<Type> ();
}
inline void end_serialize (void)
{
DEBUG_MSG_LEVEL (SERIALIZE, this->start, 0, -1,
"end [%p..%p] serialized %d bytes; %s",
this->start, this->end,
(int) (this->head - this->start),
this->ran_out_of_room ? "RAN OUT OF ROOM" : "did not ran out of room");
}
template <typename Type>
inline Type *copy (void)
{
assert (!this->ran_out_of_room);
unsigned int len = this->head - this->start;
void *p = malloc (len);
if (p)
memcpy (p, this->start, len);
return reinterpret_cast<Type *> (p);
}
template <typename Type>
inline Type *allocate_size (unsigned int size)
{
if (unlikely (this->ran_out_of_room || this->end - this->head < ptrdiff_t (size))) {
this->ran_out_of_room = true;
return NULL;
}
memset (this->head, 0, size);
char *ret = this->head;
this->head += size;
return reinterpret_cast<Type *> (ret);
}
template <typename Type>
inline Type *allocate_min (void)
{
return this->allocate_size<Type> (Type::min_size);
}
template <typename Type>
inline Type *start_embed (void)
{
Type *ret = reinterpret_cast<Type *> (this->head);
return ret;
}
template <typename Type>
inline Type *embed (const Type &obj)
{
unsigned int size = obj.get_size ();
Type *ret = this->allocate_size<Type> (size);
if (unlikely (!ret)) return NULL;
memcpy (ret, obj, size);
return ret;
}
template <typename Type>
inline Type *extend_min (Type &obj)
{
unsigned int size = obj.min_size;
assert (this->start <= (char *) &obj && (char *) &obj <= this->head && (char *) &obj + size >= this->head);
if (unlikely (!this->allocate_size<Type> (((char *) &obj) + size - this->head))) return NULL;
return reinterpret_cast<Type *> (&obj);
}
template <typename Type>
inline Type *extend (Type &obj)
{
unsigned int size = obj.get_size ();
assert (this->start < (char *) &obj && (char *) &obj <= this->head && (char *) &obj + size >= this->head);
if (unlikely (!this->allocate_size<Type> (((char *) &obj) + size - this->head))) return NULL;
return reinterpret_cast<Type *> (&obj);
}
inline void truncate (void *new_head)
{
assert (this->start < new_head && new_head <= this->head);
this->head = (char *) new_head;
}
unsigned int debug_depth;
char *start, *end, *head;
bool ran_out_of_room;
};
template <typename Type>
struct Supplier
{
inline Supplier (const Type *array, unsigned int len_)
{
head = array;
len = len_;
}
inline const Type operator [] (unsigned int i) const
{
if (unlikely (i >= len)) return Type ();
return head[i];
}
inline void advance (unsigned int count)
{
if (unlikely (count > len))
count = len;
len -= count;
head += count;
}
private:
inline Supplier (const Supplier<Type> &); /* Disallow copy */
inline Supplier<Type>& operator= (const Supplier<Type> &); /* Disallow copy */
unsigned int len;
const Type *head;
};
/*
*
* 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
*/
template <typename Type, int Bytes> struct BEInt;
template <typename Type>
struct BEInt<Type, 1>
{
public:
inline void set (Type V)
{
v = V;
}
inline operator Type (void) const
{
return v;
}
private: uint8_t v;
};
template <typename Type>
struct BEInt<Type, 2>
{
public:
inline void set (Type V)
{
v[0] = (V >> 8) & 0xFF;
v[1] = (V ) & 0xFF;
}
inline operator Type (void) const
{
return (v[0] << 8)
+ (v[1] );
}
private: uint8_t v[2];
};
template <typename Type>
struct BEInt<Type, 3>
{
public:
inline void set (Type V)
{
v[0] = (V >> 16) & 0xFF;
v[1] = (V >> 8) & 0xFF;
v[2] = (V ) & 0xFF;
}
inline operator Type (void) const
{
return (v[0] << 16)
+ (v[1] << 8)
+ (v[2] );
}
private: uint8_t v[3];
};
template <typename Type>
struct BEInt<Type, 4>
{
public:
inline void set (Type V)
{
v[0] = (V >> 24) & 0xFF;
v[1] = (V >> 16) & 0xFF;
v[2] = (V >> 8) & 0xFF;
v[3] = (V ) & 0xFF;
}
inline operator Type (void) const
{
return (v[0] << 24)
+ (v[1] << 16)
+ (v[2] << 8)
+ (v[3] );
}
private: uint8_t v[4];
};
/* Integer types in big-endian order and no alignment requirement */
template <typename Type, unsigned int Size>
struct IntType
{
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); }
inline int cmp (Type a) const
{
Type b = v;
if (sizeof (Type) < 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> BYTE; /* 8-bit unsigned integer. */
typedef IntType<uint16_t, 2> USHORT; /* 16-bit unsigned integer. */
typedef IntType<int16_t, 2> SHORT; /* 16-bit signed integer. */
typedef IntType<uint32_t, 4> ULONG; /* 32-bit unsigned integer. */
typedef IntType<int32_t, 4> LONG; /* 32-bit signed integer. */
typedef IntType<uint32_t, 3> UINT24; /* 24-bit unsigned integer. */
/* 16-bit signed integer (SHORT) that describes a quantity in FUnits. */
typedef SHORT FWORD;
/* 16-bit unsigned integer (USHORT) that describes a quantity in FUnits. */
typedef USHORT UFWORD;
/* 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:
LONG major;
ULONG 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 : ULONG
{
/* 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);
};
DEFINE_NULL_DATA (Tag, " ");
/* Glyph index number, same as uint16 (length = 16 bits) */
struct GlyphID : USHORT {
static inline int cmp (const GlyphID *a, const GlyphID *b) { return b->USHORT::cmp (*a); }
inline int cmp (hb_codepoint_t a) const { return (int) a - (int) *this; }
};
/* Script/language-system/feature index */
struct Index : USHORT {
static const unsigned int NOT_FOUND_INDEX = 0xFFFFu;
};
DEFINE_NULL_DATA (Index, "\xff\xff");
/* Offset, Null offset = 0 */
template <typename Type=USHORT>
struct Offset : Type
{
inline bool is_null (void) const { return 0 == *this; }
public:
DEFINE_SIZE_STATIC (sizeof(Type));
};
/* CheckSum */
struct CheckSum : ULONG
{
/* This is reference implementation from the spec. */
static inline uint32_t CalcTableChecksum (const ULONG *Table, uint32_t Length)
{
uint32_t Sum = 0L;
const ULONG *EndPtr = Table+((Length+3) & ~3) / ULONG::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 ULONG *) data, length)); }
public:
DEFINE_SIZE_STATIC (4);
};
/*
* Version Numbers
*/
struct FixedVersion
{
inline uint32_t to_int (void) const { return (major << 16) + minor; }
inline bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (c->check_struct (this));
}
USHORT major;
USHORT minor;
public:
DEFINE_SIZE_STATIC (4);
};
/*
* Template subclasses of Offset that do the dereferencing.
* Use: (base+offset)
*/
template <typename Type, typename OffsetType=USHORT>
struct OffsetTo : Offset<OffsetType>
{
inline const Type& operator () (const void *base) const
{
unsigned int offset = *this;
if (unlikely (!offset)) return Null(Type);
return StructAtOffset<Type> (base, offset);
}
inline Type& serialize (hb_serialize_context_t *c, const void *base)
{
Type *t = c->start_embed<Type> ();
this->set ((char *) t - (char *) base); /* TODO(serialize) Overflow? */
return *t;
}
inline bool sanitize (hb_sanitize_context_t *c, const void *base) const
{
TRACE_SANITIZE (this);
if (unlikely (!c->check_struct (this))) return_trace (false);
unsigned int offset = *this;
if (unlikely (!offset)) return_trace (true);
const Type &obj = StructAtOffset<Type> (base, offset);
return_trace (likely (obj.sanitize (c)) || neuter (c));
}
template <typename T>
inline bool sanitize (hb_sanitize_context_t *c, const void *base, T user_data) const
{
TRACE_SANITIZE (this);
if (unlikely (!c->check_struct (this))) return_trace (false);
unsigned int offset = *this;
if (unlikely (!offset)) return_trace (true);
const Type &obj = StructAtOffset<Type> (base, offset);
return_trace (likely (obj.sanitize (c, user_data)) || neuter (c));
}
/* Set the offset to Null */
inline bool neuter (hb_sanitize_context_t *c) const {
return c->try_set (this, 0);
}
DEFINE_SIZE_STATIC (sizeof(OffsetType));
};
template <typename Base, typename OffsetType, typename Type>
static inline const Type& operator + (const Base &base, const OffsetTo<Type, OffsetType> &offset) { return offset (base); }
template <typename Base, typename OffsetType, typename Type>
static inline Type& operator + (Base &base, OffsetTo<Type, OffsetType> &offset) { return offset (base); }
/*
* Array Types
*/
/* An array with a number of elements. */
template <typename Type, typename LenType=USHORT>
struct ArrayOf
{
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 array + start_offset;
}
inline const Type& operator [] (unsigned int i) const
{
if (unlikely (i >= len)) return Null(Type);
return array[i];
}
inline Type& operator [] (unsigned int i)
{
return array[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++)
array[i] = items[i];
items.advance (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 && array[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 (!array[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 (!array[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->array[i].cmp (x))
return i;
return -1;
}
private:
inline bool sanitize_shallow (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (c->check_struct (this) && c->check_array (array, Type::static_size, len));
}
public:
LenType len;
Type array[VAR];
public:
DEFINE_SIZE_ARRAY (sizeof (LenType), array);
};
/* Array of Offset's */
template <typename Type>
struct OffsetArrayOf : ArrayOf<OffsetTo<Type> > {};
/* 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->array[i];
}
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=USHORT>
struct HeadlessArrayOf
{
inline const Type& operator [] (unsigned int i) const
{
if (unlikely (i >= len || !i)) return Null(Type);
return array[i-1];
}
inline unsigned int get_size (void) const
{ return len.static_size + (len ? len - 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);
len.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++)
array[i] = items[i];
items.advance (items_len - 1);
return_trace (true);
}
inline bool sanitize_shallow (hb_sanitize_context_t *c) const
{
return c->check_struct (this)
&& c->check_array (this, Type::static_size, len);
}
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 && array[0].sanitize (c));
return_trace (true);
}
LenType len;
Type array[VAR];
public:
DEFINE_SIZE_ARRAY (sizeof (LenType), array);
};
/* An array with sorted elements. Supports binary searching. */
template <typename Type, typename LenType=USHORT>
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. */
int min = 0, max = (int) this->len - 1;
while (min <= max)
{
int mid = (min + max) / 2;
int c = this->array[mid].cmp (x);
if (c < 0)
max = mid - 1;
else if (c > 0)
min = mid + 1;
else
return mid;
}
return -1;
}
};
} /* namespace OT */
#endif /* HB_OPEN_TYPE_PRIVATE_HH */
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