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Diffstat (limited to 'src/3rdparty/harfbuzz-ng/src/hb-open-type-private.hh')
| -rw-r--r-- | src/3rdparty/harfbuzz-ng/src/hb-open-type-private.hh | 981 |
1 files changed, 981 insertions, 0 deletions
diff --git a/src/3rdparty/harfbuzz-ng/src/hb-open-type-private.hh b/src/3rdparty/harfbuzz-ng/src/hb-open-type-private.hh new file mode 100644 index 0000000000..ee3a21dc3b --- /dev/null +++ b/src/3rdparty/harfbuzz-ng/src/hb-open-type-private.hh @@ -0,0 +1,981 @@ +/* + * 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" + +#include "hb-blob.h" + + +namespace OT { + + + +/* + * Casts + */ + +/* Cast to struct T, reference to reference */ +template<typename Type, typename TObject> +inline const Type& CastR(const TObject &X) +{ return reinterpret_cast<const Type&> (X); } +template<typename Type, typename TObject> +inline Type& CastR(TObject &X) +{ return reinterpret_cast<Type&> (X); } + +/* Cast to struct T, pointer to pointer */ +template<typename Type, typename TObject> +inline const Type* CastP(const TObject *X) +{ return reinterpret_cast<const Type*> (X); } +template<typename Type, typename TObject> +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> +inline const Type& StructAtOffset(const void *P, unsigned int offset) +{ return * reinterpret_cast<const Type*> ((const char *) P + offset); } +template<typename Type> +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> +inline const Type& StructAfter(const TObject &X) +{ return StructAtOffset<Type>(&X, X.get_size()); } +template<typename Type, typename TObject> +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[64 / 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 <> \ +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>() + + + +/* + * 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 100 +#endif + +struct hb_sanitize_context_t +{ + inline const char *get_name (void) { return "SANITIZE"; } + static const unsigned int max_debug_depth = HB_DEBUG_SANITIZE; + typedef bool return_t; + template <typename T> + inline return_t dispatch (const T &obj) { return obj.sanitize (this); } + static return_t default_return_value (void) { return true; } + bool stop_sublookup_iteration (const return_t r HB_UNUSED) const { return false; } + + 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); + this->edit_count = 0; + this->debug_depth = 0; + + DEBUG_MSG_LEVEL (SANITIZE, this->blob, 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->blob, 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; + + hb_auto_trace_t<HB_DEBUG_SANITIZE, bool> trace + (&this->debug_depth, "SANITIZE", this->blob, NULL, + "check_range [%p..%p] (%d bytes) in [%p..%p]", + p, p + len, len, + this->start, this->end); + + return TRACE_RETURN (likely (this->start <= p && p <= this->end && (unsigned int) (this->end - p) >= len)); + } + + 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); + + hb_auto_trace_t<HB_DEBUG_SANITIZE, bool> trace + (&this->debug_depth, "SANITIZE", this->blob, NULL, + "check_array [%p..%p] (%d*%d=%ld bytes) in [%p..%p]", + p, p + (record_size * len), record_size, len, (unsigned long) record_size * len, + this->start, this->end); + + return TRACE_RETURN (likely (!overflows && this->check_range (base, record_size * len))); + } + + 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++; + + hb_auto_trace_t<HB_DEBUG_SANITIZE, bool> trace + (&this->debug_depth, "SANITIZE", this->blob, NULL, + "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 TRACE_RETURN (this->writable); + } + + 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] = {{0}}; + bool sane; + + /* TODO is_sane() stuff */ + + c->init (blob); + + retry: + DEBUG_MSG_FUNC (SANITIZE, blob, "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, blob, "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, blob, "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, blob, "retry"); + goto retry; + } + } + } + + c->end_processing (); + + DEBUG_MSG_FUNC (SANITIZE, blob, 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 *head) + { + assert (this->start < head && head <= this->head); + this->head = (char *) 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, 2> +{ + public: + inline void set (Type i) { hb_be_uint16_put (v,i); } + inline operator Type (void) const { return hb_be_uint16_get (v); } + inline bool operator == (const BEInt<Type, 2>& o) const { return hb_be_uint16_eq (v, o.v); } + inline bool operator != (const BEInt<Type, 2>& o) const { return !(*this == o); } + private: uint8_t v[2]; +}; +template <typename Type> +struct BEInt<Type, 4> +{ + public: + inline void set (Type i) { hb_be_uint32_put (v,i); } + inline operator Type (void) const { return hb_be_uint32_get (v); } + inline bool operator == (const BEInt<Type, 4>& o) const { return hb_be_uint32_eq (v, o.v); } + inline bool operator != (const BEInt<Type, 4>& o) const { return !(*this == o); } + private: uint8_t v[4]; +}; +template <typename Type> +struct BEInt<Type, 3> +{ + public: + inline void set (Type i) { hb_be_uint24_put (v,i); } + inline operator Type (void) const { return hb_be_uint24_get (v); } + inline bool operator == (const BEInt<Type, 3>& o) const { return hb_be_uint24_eq (v, o.v); } + inline bool operator != (const BEInt<Type, 3>& o) const { return !(*this == o); } + private: uint8_t v[3]; +}; + +/* 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 v == o.v; } + inline bool operator != (const IntType<Type,Size> &o) const { return v != o.v; } + static inline int cmp (const IntType<Type,Size> *a, const IntType<Type,Size> *b) { return b->cmp (*a); } + inline int cmp (IntType<Type,Size> va) const { Type a = va; Type b = v; return a < b ? -1 : a == b ? 0 : +1; } + inline int cmp (Type a) const { Type b = v; return a < b ? -1 : a == b ? 0 : +1; } + inline bool sanitize (hb_sanitize_context_t *c) { + TRACE_SANITIZE (this); + return TRACE_RETURN (likely (c->check_struct (this))); + } + protected: + BEInt<Type, Size> v; + public: + DEFINE_SIZE_STATIC (Size); +}; + +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) { + TRACE_SANITIZE (this); + return TRACE_RETURN (likely (c->check_struct (this))); + } + private: + 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) */ +typedef USHORT GlyphID; + +/* Script/language-system/feature index */ +struct Index : USHORT { + static const unsigned int NOT_FOUND_INDEX = 0xFFFF; +}; +DEFINE_NULL_DATA (Index, "\xff\xff"); + +/* Offset to a table, same as uint16 (length = 16 bits), Null offset = 0x0000 */ +struct Offset : USHORT +{ + inline bool is_null (void) const { return 0 == *this; } + public: + DEFINE_SIZE_STATIC (2); +}; + +/* LongOffset to a table, same as uint32 (length = 32 bits), Null offset = 0x00000000 */ +struct LongOffset : ULONG +{ + inline bool is_null (void) const { return 0 == *this; } + public: + DEFINE_SIZE_STATIC (4); +}; + + +/* 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) { + TRACE_SANITIZE (this); + return TRACE_RETURN (c->check_struct (this)); + } + + USHORT major; + USHORT minor; + public: + DEFINE_SIZE_STATIC (4); +}; + + + +/* + * Template subclasses of Offset and LongOffset that do the dereferencing. + * Use: (base+offset) + */ + +template <typename OffsetType, typename Type> +struct GenericOffsetTo : 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, 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, void *base) { + TRACE_SANITIZE (this); + if (unlikely (!c->check_struct (this))) return TRACE_RETURN (false); + unsigned int offset = *this; + if (unlikely (!offset)) return TRACE_RETURN (true); + Type &obj = StructAtOffset<Type> (base, offset); + return TRACE_RETURN (likely (obj.sanitize (c)) || neuter (c)); + } + template <typename T> + inline bool sanitize (hb_sanitize_context_t *c, void *base, T user_data) { + TRACE_SANITIZE (this); + if (unlikely (!c->check_struct (this))) return TRACE_RETURN (false); + unsigned int offset = *this; + if (unlikely (!offset)) return TRACE_RETURN (true); + Type &obj = StructAtOffset<Type> (base, offset); + return TRACE_RETURN (likely (obj.sanitize (c, user_data)) || neuter (c)); + } + + inline bool try_set (hb_sanitize_context_t *c, const OffsetType &v) { + if (c->may_edit (this, this->static_size)) { + this->set (v); + return true; + } + return false; + } + /* Set the offset to Null */ + inline bool neuter (hb_sanitize_context_t *c) { + if (c->may_edit (this, this->static_size)) { + this->set (0); /* 0 is Null offset */ + return true; + } + return false; + } +}; +template <typename Base, typename OffsetType, typename Type> +inline const Type& operator + (const Base &base, const GenericOffsetTo<OffsetType, Type> &offset) { return offset (base); } +template <typename Base, typename OffsetType, typename Type> +inline Type& operator + (Base &base, GenericOffsetTo<OffsetType, Type> &offset) { return offset (base); } + +template <typename Type> +struct OffsetTo : GenericOffsetTo<Offset, Type> {}; + +template <typename Type> +struct LongOffsetTo : GenericOffsetTo<LongOffset, Type> {}; + + +/* + * Array Types + */ + +template <typename LenType, typename Type> +struct GenericArrayOf +{ + 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_RETURN (false); + len.set (items_len); /* TODO(serialize) Overflow? */ + if (unlikely (!c->extend (*this))) return TRACE_RETURN (false); + return TRACE_RETURN (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_RETURN (false); + for (unsigned int i = 0; i < items_len; i++) + array[i] = items[i]; + items.advance (items_len); + return TRACE_RETURN (true); + } + + inline bool sanitize (hb_sanitize_context_t *c) { + TRACE_SANITIZE (this); + if (unlikely (!sanitize_shallow (c))) return TRACE_RETURN (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_RETURN (true); + } + inline bool sanitize (hb_sanitize_context_t *c, void *base) { + TRACE_SANITIZE (this); + if (unlikely (!sanitize_shallow (c))) return TRACE_RETURN (false); + unsigned int count = len; + for (unsigned int i = 0; i < count; i++) + if (unlikely (!array[i].sanitize (c, base))) + return TRACE_RETURN (false); + return TRACE_RETURN (true); + } + template <typename T> + inline bool sanitize (hb_sanitize_context_t *c, void *base, T user_data) { + TRACE_SANITIZE (this); + if (unlikely (!sanitize_shallow (c))) return TRACE_RETURN (false); + unsigned int count = len; + for (unsigned int i = 0; i < count; i++) + if (unlikely (!array[i].sanitize (c, base, user_data))) + return TRACE_RETURN (false); + return TRACE_RETURN (true); + } + + private: + inline bool sanitize_shallow (hb_sanitize_context_t *c) { + TRACE_SANITIZE (this); + return TRACE_RETURN (c->check_struct (this) && c->check_array (this, Type::static_size, len)); + } + + public: + LenType len; + Type array[VAR]; + public: + DEFINE_SIZE_ARRAY (sizeof (LenType), array); +}; + +/* An array with a USHORT number of elements. */ +template <typename Type> +struct ArrayOf : GenericArrayOf<USHORT, Type> {}; + +/* An array with a ULONG number of elements. */ +template <typename Type> +struct LongArrayOf : GenericArrayOf<ULONG, Type> {}; + +/* Array of Offset's */ +template <typename Type> +struct OffsetArrayOf : ArrayOf<OffsetTo<Type> > {}; + +/* Array of LongOffset's */ +template <typename Type> +struct LongOffsetArrayOf : ArrayOf<LongOffsetTo<Type> > {}; + +/* LongArray of LongOffset's */ +template <typename Type> +struct LongOffsetLongArrayOf : LongArrayOf<LongOffsetTo<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) { + TRACE_SANITIZE (this); + return TRACE_RETURN (OffsetArrayOf<Type>::sanitize (c, this)); + } + template <typename T> + inline bool sanitize (hb_sanitize_context_t *c, T user_data) { + TRACE_SANITIZE (this); + return TRACE_RETURN (OffsetArrayOf<Type>::sanitize (c, this, user_data)); + } +}; + + +/* An array with a USHORT number of elements, + * starting at second element. */ +template <typename Type> +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_RETURN (false); + len.set (items_len); /* TODO(serialize) Overflow? */ + if (unlikely (!items_len)) return TRACE_RETURN (true); + if (unlikely (!c->extend (*this))) return TRACE_RETURN (false); + for (unsigned int i = 0; i < items_len - 1; i++) + array[i] = items[i]; + items.advance (items_len - 1); + return TRACE_RETURN (true); + } + + inline bool sanitize_shallow (hb_sanitize_context_t *c) { + return c->check_struct (this) + && c->check_array (this, Type::static_size, len); + } + + inline bool sanitize (hb_sanitize_context_t *c) { + TRACE_SANITIZE (this); + if (unlikely (!sanitize_shallow (c))) return TRACE_RETURN (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_RETURN (true); + } + + USHORT len; + Type array[VAR]; + public: + DEFINE_SIZE_ARRAY (sizeof (USHORT), array); +}; + + +/* An array with sorted elements. Supports binary searching. */ +template <typename Type> +struct SortedArrayOf : ArrayOf<Type> { + + template <typename SearchType> + inline int search (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 */ |