michael@0: /*
michael@0:  * Copyright © 2007,2008,2009,2010  Red Hat, Inc.
michael@0:  * Copyright © 2012  Google, Inc.
michael@0:  *
michael@0:  *  This is part of HarfBuzz, a text shaping library.
michael@0:  *
michael@0:  * Permission is hereby granted, without written agreement and without
michael@0:  * license or royalty fees, to use, copy, modify, and distribute this
michael@0:  * software and its documentation for any purpose, provided that the
michael@0:  * above copyright notice and the following two paragraphs appear in
michael@0:  * all copies of this software.
michael@0:  *
michael@0:  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
michael@0:  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
michael@0:  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
michael@0:  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
michael@0:  * DAMAGE.
michael@0:  *
michael@0:  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
michael@0:  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
michael@0:  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
michael@0:  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
michael@0:  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
michael@0:  *
michael@0:  * Red Hat Author(s): Behdad Esfahbod
michael@0:  * Google Author(s): Behdad Esfahbod
michael@0:  */
michael@0: 
michael@0: #ifndef HB_OPEN_TYPE_PRIVATE_HH
michael@0: #define HB_OPEN_TYPE_PRIVATE_HH
michael@0: 
michael@0: #include "hb-private.hh"
michael@0: 
michael@0: 
michael@0: namespace OT {
michael@0: 
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * Casts
michael@0:  */
michael@0: 
michael@0: /* Cast to struct T, reference to reference */
michael@0: template<typename Type, typename TObject>
michael@0: inline const Type& CastR(const TObject &X)
michael@0: { return reinterpret_cast<const Type&> (X); }
michael@0: template<typename Type, typename TObject>
michael@0: inline Type& CastR(TObject &X)
michael@0: { return reinterpret_cast<Type&> (X); }
michael@0: 
michael@0: /* Cast to struct T, pointer to pointer */
michael@0: template<typename Type, typename TObject>
michael@0: inline const Type* CastP(const TObject *X)
michael@0: { return reinterpret_cast<const Type*> (X); }
michael@0: template<typename Type, typename TObject>
michael@0: inline Type* CastP(TObject *X)
michael@0: { return reinterpret_cast<Type*> (X); }
michael@0: 
michael@0: /* StructAtOffset<T>(P,Ofs) returns the struct T& that is placed at memory
michael@0:  * location pointed to by P plus Ofs bytes. */
michael@0: template<typename Type>
michael@0: inline const Type& StructAtOffset(const void *P, unsigned int offset)
michael@0: { return * reinterpret_cast<const Type*> ((const char *) P + offset); }
michael@0: template<typename Type>
michael@0: inline Type& StructAtOffset(void *P, unsigned int offset)
michael@0: { return * reinterpret_cast<Type*> ((char *) P + offset); }
michael@0: 
michael@0: /* StructAfter<T>(X) returns the struct T& that is placed after X.
michael@0:  * Works with X of variable size also.  X must implement get_size() */
michael@0: template<typename Type, typename TObject>
michael@0: inline const Type& StructAfter(const TObject &X)
michael@0: { return StructAtOffset<Type>(&X, X.get_size()); }
michael@0: template<typename Type, typename TObject>
michael@0: inline Type& StructAfter(TObject &X)
michael@0: { return StructAtOffset<Type>(&X, X.get_size()); }
michael@0: 
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * Size checking
michael@0:  */
michael@0: 
michael@0: /* Check _assertion in a method environment */
michael@0: #define _DEFINE_INSTANCE_ASSERTION1(_line, _assertion) \
michael@0:   inline void _instance_assertion_on_line_##_line (void) const \
michael@0:   { \
michael@0:     ASSERT_STATIC (_assertion); \
michael@0:     ASSERT_INSTANCE_POD (*this); /* Make sure it's POD. */ \
michael@0:   }
michael@0: # define _DEFINE_INSTANCE_ASSERTION0(_line, _assertion) _DEFINE_INSTANCE_ASSERTION1 (_line, _assertion)
michael@0: # define DEFINE_INSTANCE_ASSERTION(_assertion) _DEFINE_INSTANCE_ASSERTION0 (__LINE__, _assertion)
michael@0: 
michael@0: /* Check that _code compiles in a method environment */
michael@0: #define _DEFINE_COMPILES_ASSERTION1(_line, _code) \
michael@0:   inline void _compiles_assertion_on_line_##_line (void) const \
michael@0:   { _code; }
michael@0: # define _DEFINE_COMPILES_ASSERTION0(_line, _code) _DEFINE_COMPILES_ASSERTION1 (_line, _code)
michael@0: # define DEFINE_COMPILES_ASSERTION(_code) _DEFINE_COMPILES_ASSERTION0 (__LINE__, _code)
michael@0: 
michael@0: 
michael@0: #define DEFINE_SIZE_STATIC(size) \
michael@0:   DEFINE_INSTANCE_ASSERTION (sizeof (*this) == (size)); \
michael@0:   static const unsigned int static_size = (size); \
michael@0:   static const unsigned int min_size = (size)
michael@0: 
michael@0: /* Size signifying variable-sized array */
michael@0: #define VAR 1
michael@0: 
michael@0: #define DEFINE_SIZE_UNION(size, _member) \
michael@0:   DEFINE_INSTANCE_ASSERTION (this->u._member.static_size == (size)); \
michael@0:   static const unsigned int min_size = (size)
michael@0: 
michael@0: #define DEFINE_SIZE_MIN(size) \
michael@0:   DEFINE_INSTANCE_ASSERTION (sizeof (*this) >= (size)); \
michael@0:   static const unsigned int min_size = (size)
michael@0: 
michael@0: #define DEFINE_SIZE_ARRAY(size, array) \
michael@0:   DEFINE_INSTANCE_ASSERTION (sizeof (*this) == (size) + sizeof (array[0])); \
michael@0:   DEFINE_COMPILES_ASSERTION ((void) array[0].static_size) \
michael@0:   static const unsigned int min_size = (size)
michael@0: 
michael@0: #define DEFINE_SIZE_ARRAY2(size, array1, array2) \
michael@0:   DEFINE_INSTANCE_ASSERTION (sizeof (*this) == (size) + sizeof (this->array1[0]) + sizeof (this->array2[0])); \
michael@0:   DEFINE_COMPILES_ASSERTION ((void) array1[0].static_size; (void) array2[0].static_size) \
michael@0:   static const unsigned int min_size = (size)
michael@0: 
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * Null objects
michael@0:  */
michael@0: 
michael@0: /* Global nul-content Null pool.  Enlarge as necessary. */
michael@0: /* TODO This really should be a extern HB_INTERNAL and defined somewhere... */
michael@0: static const void *_NullPool[64 / sizeof (void *)];
michael@0: 
michael@0: /* Generic nul-content Null objects. */
michael@0: template <typename Type>
michael@0: static inline const Type& Null (void) {
michael@0:   ASSERT_STATIC (sizeof (Type) <= sizeof (_NullPool));
michael@0:   return *CastP<Type> (_NullPool);
michael@0: }
michael@0: 
michael@0: /* Specializaiton for arbitrary-content arbitrary-sized Null objects. */
michael@0: #define DEFINE_NULL_DATA(Type, data) \
michael@0: static const char _Null##Type[sizeof (Type) + 1] = data; /* +1 is for nul-termination in data */ \
michael@0: template <> \
michael@0: inline const Type& Null<Type> (void) { \
michael@0:   return *CastP<Type> (_Null##Type); \
michael@0: } /* The following line really exists such that we end in a place needing semicolon */ \
michael@0: ASSERT_STATIC (Type::min_size + 1 <= sizeof (_Null##Type))
michael@0: 
michael@0: /* Accessor macro. */
michael@0: #define Null(Type) Null<Type>()
michael@0: 
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * Sanitize
michael@0:  */
michael@0: 
michael@0: #ifndef HB_DEBUG_SANITIZE
michael@0: #define HB_DEBUG_SANITIZE (HB_DEBUG+0)
michael@0: #endif
michael@0: 
michael@0: 
michael@0: #define TRACE_SANITIZE(this) \
michael@0: 	hb_auto_trace_t<HB_DEBUG_SANITIZE, bool> trace \
michael@0: 	(&c->debug_depth, c->get_name (), this, HB_FUNC, \
michael@0: 	 "");
michael@0: 
michael@0: /* This limits sanitizing time on really broken fonts. */
michael@0: #ifndef HB_SANITIZE_MAX_EDITS
michael@0: #define HB_SANITIZE_MAX_EDITS 100
michael@0: #endif
michael@0: 
michael@0: struct hb_sanitize_context_t
michael@0: {
michael@0:   inline const char *get_name (void) { return "SANITIZE"; }
michael@0:   static const unsigned int max_debug_depth = HB_DEBUG_SANITIZE;
michael@0:   typedef bool return_t;
michael@0:   template <typename T>
michael@0:   inline return_t dispatch (const T &obj) { return obj.sanitize (this); }
michael@0:   static return_t default_return_value (void) { return true; }
michael@0:   bool stop_sublookup_iteration (const return_t r HB_UNUSED) const { return false; }
michael@0: 
michael@0:   inline void init (hb_blob_t *b)
michael@0:   {
michael@0:     this->blob = hb_blob_reference (b);
michael@0:     this->writable = false;
michael@0:   }
michael@0: 
michael@0:   inline void start_processing (void)
michael@0:   {
michael@0:     this->start = hb_blob_get_data (this->blob, NULL);
michael@0:     this->end = this->start + hb_blob_get_length (this->blob);
michael@0:     this->edit_count = 0;
michael@0:     this->debug_depth = 0;
michael@0: 
michael@0:     DEBUG_MSG_LEVEL (SANITIZE, this->blob, 0, +1,
michael@0: 		     "start [%p..%p] (%lu bytes)",
michael@0: 		     this->start, this->end,
michael@0: 		     (unsigned long) (this->end - this->start));
michael@0:   }
michael@0: 
michael@0:   inline void end_processing (void)
michael@0:   {
michael@0:     DEBUG_MSG_LEVEL (SANITIZE, this->blob, 0, -1,
michael@0: 		     "end [%p..%p] %u edit requests",
michael@0: 		     this->start, this->end, this->edit_count);
michael@0: 
michael@0:     hb_blob_destroy (this->blob);
michael@0:     this->blob = NULL;
michael@0:     this->start = this->end = NULL;
michael@0:   }
michael@0: 
michael@0:   inline bool check_range (const void *base, unsigned int len) const
michael@0:   {
michael@0:     const char *p = (const char *) base;
michael@0: 
michael@0:     hb_auto_trace_t<HB_DEBUG_SANITIZE, bool> trace
michael@0:       (&this->debug_depth, "SANITIZE", this->blob, NULL,
michael@0:        "check_range [%p..%p] (%d bytes) in [%p..%p]",
michael@0:        p, p + len, len,
michael@0:        this->start, this->end);
michael@0: 
michael@0:     return TRACE_RETURN (likely (this->start <= p && p <= this->end && (unsigned int) (this->end - p) >= len));
michael@0:   }
michael@0: 
michael@0:   inline bool check_array (const void *base, unsigned int record_size, unsigned int len) const
michael@0:   {
michael@0:     const char *p = (const char *) base;
michael@0:     bool overflows = _hb_unsigned_int_mul_overflows (len, record_size);
michael@0: 
michael@0:     hb_auto_trace_t<HB_DEBUG_SANITIZE, bool> trace
michael@0:       (&this->debug_depth, "SANITIZE", this->blob, NULL,
michael@0:        "check_array [%p..%p] (%d*%d=%ld bytes) in [%p..%p]",
michael@0:        p, p + (record_size * len), record_size, len, (unsigned long) record_size * len,
michael@0:        this->start, this->end);
michael@0: 
michael@0:     return TRACE_RETURN (likely (!overflows && this->check_range (base, record_size * len)));
michael@0:   }
michael@0: 
michael@0:   template <typename Type>
michael@0:   inline bool check_struct (const Type *obj) const
michael@0:   {
michael@0:     return likely (this->check_range (obj, obj->min_size));
michael@0:   }
michael@0: 
michael@0:   inline bool may_edit (const void *base HB_UNUSED, unsigned int len HB_UNUSED)
michael@0:   {
michael@0:     if (this->edit_count >= HB_SANITIZE_MAX_EDITS)
michael@0:       return false;
michael@0: 
michael@0:     const char *p = (const char *) base;
michael@0:     this->edit_count++;
michael@0: 
michael@0:     hb_auto_trace_t<HB_DEBUG_SANITIZE, bool> trace
michael@0:       (&this->debug_depth, "SANITIZE", this->blob, NULL,
michael@0:        "may_edit(%u) [%p..%p] (%d bytes) in [%p..%p] -> %s",
michael@0:        this->edit_count,
michael@0:        p, p + len, len,
michael@0:        this->start, this->end,
michael@0:        this->writable ? "GRANTED" : "DENIED");
michael@0: 
michael@0:     return TRACE_RETURN (this->writable);
michael@0:   }
michael@0: 
michael@0:   mutable unsigned int debug_depth;
michael@0:   const char *start, *end;
michael@0:   bool writable;
michael@0:   unsigned int edit_count;
michael@0:   hb_blob_t *blob;
michael@0: };
michael@0: 
michael@0: 
michael@0: 
michael@0: /* Template to sanitize an object. */
michael@0: template <typename Type>
michael@0: struct Sanitizer
michael@0: {
michael@0:   static hb_blob_t *sanitize (hb_blob_t *blob) {
michael@0:     hb_sanitize_context_t c[1] = {{0}};
michael@0:     bool sane;
michael@0: 
michael@0:     /* TODO is_sane() stuff */
michael@0: 
michael@0:     c->init (blob);
michael@0: 
michael@0:   retry:
michael@0:     DEBUG_MSG_FUNC (SANITIZE, blob, "start");
michael@0: 
michael@0:     c->start_processing ();
michael@0: 
michael@0:     if (unlikely (!c->start)) {
michael@0:       c->end_processing ();
michael@0:       return blob;
michael@0:     }
michael@0: 
michael@0:     Type *t = CastP<Type> (const_cast<char *> (c->start));
michael@0: 
michael@0:     sane = t->sanitize (c);
michael@0:     if (sane) {
michael@0:       if (c->edit_count) {
michael@0: 	DEBUG_MSG_FUNC (SANITIZE, blob, "passed first round with %d edits; going for second round", c->edit_count);
michael@0: 
michael@0:         /* sanitize again to ensure no toe-stepping */
michael@0:         c->edit_count = 0;
michael@0: 	sane = t->sanitize (c);
michael@0: 	if (c->edit_count) {
michael@0: 	  DEBUG_MSG_FUNC (SANITIZE, blob, "requested %d edits in second round; FAILLING", c->edit_count);
michael@0: 	  sane = false;
michael@0: 	}
michael@0:       }
michael@0:     } else {
michael@0:       unsigned int edit_count = c->edit_count;
michael@0:       if (edit_count && !c->writable) {
michael@0:         c->start = hb_blob_get_data_writable (blob, NULL);
michael@0: 	c->end = c->start + hb_blob_get_length (blob);
michael@0: 
michael@0: 	if (c->start) {
michael@0: 	  c->writable = true;
michael@0: 	  /* ok, we made it writable by relocating.  try again */
michael@0: 	  DEBUG_MSG_FUNC (SANITIZE, blob, "retry");
michael@0: 	  goto retry;
michael@0: 	}
michael@0:       }
michael@0:     }
michael@0: 
michael@0:     c->end_processing ();
michael@0: 
michael@0:     DEBUG_MSG_FUNC (SANITIZE, blob, sane ? "PASSED" : "FAILED");
michael@0:     if (sane)
michael@0:       return blob;
michael@0:     else {
michael@0:       hb_blob_destroy (blob);
michael@0:       return hb_blob_get_empty ();
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   static const Type* lock_instance (hb_blob_t *blob) {
michael@0:     hb_blob_make_immutable (blob);
michael@0:     const char *base = hb_blob_get_data (blob, NULL);
michael@0:     return unlikely (!base) ? &Null(Type) : CastP<Type> (base);
michael@0:   }
michael@0: };
michael@0: 
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * Serialize
michael@0:  */
michael@0: 
michael@0: #ifndef HB_DEBUG_SERIALIZE
michael@0: #define HB_DEBUG_SERIALIZE (HB_DEBUG+0)
michael@0: #endif
michael@0: 
michael@0: 
michael@0: #define TRACE_SERIALIZE(this) \
michael@0: 	hb_auto_trace_t<HB_DEBUG_SERIALIZE, bool> trace \
michael@0: 	(&c->debug_depth, "SERIALIZE", c, HB_FUNC, \
michael@0: 	 "");
michael@0: 
michael@0: 
michael@0: struct hb_serialize_context_t
michael@0: {
michael@0:   inline hb_serialize_context_t (void *start, unsigned int size)
michael@0:   {
michael@0:     this->start = (char *) start;
michael@0:     this->end = this->start + size;
michael@0: 
michael@0:     this->ran_out_of_room = false;
michael@0:     this->head = this->start;
michael@0:     this->debug_depth = 0;
michael@0:   }
michael@0: 
michael@0:   template <typename Type>
michael@0:   inline Type *start_serialize (void)
michael@0:   {
michael@0:     DEBUG_MSG_LEVEL (SERIALIZE, this->start, 0, +1,
michael@0: 		     "start [%p..%p] (%lu bytes)",
michael@0: 		     this->start, this->end,
michael@0: 		     (unsigned long) (this->end - this->start));
michael@0: 
michael@0:     return start_embed<Type> ();
michael@0:   }
michael@0: 
michael@0:   inline void end_serialize (void)
michael@0:   {
michael@0:     DEBUG_MSG_LEVEL (SERIALIZE, this->start, 0, -1,
michael@0: 		     "end [%p..%p] serialized %d bytes; %s",
michael@0: 		     this->start, this->end,
michael@0: 		     (int) (this->head - this->start),
michael@0: 		     this->ran_out_of_room ? "RAN OUT OF ROOM" : "did not ran out of room");
michael@0: 
michael@0:   }
michael@0: 
michael@0:   template <typename Type>
michael@0:   inline Type *copy (void)
michael@0:   {
michael@0:     assert (!this->ran_out_of_room);
michael@0:     unsigned int len = this->head - this->start;
michael@0:     void *p = malloc (len);
michael@0:     if (p)
michael@0:       memcpy (p, this->start, len);
michael@0:     return reinterpret_cast<Type *> (p);
michael@0:   }
michael@0: 
michael@0:   template <typename Type>
michael@0:   inline Type *allocate_size (unsigned int size)
michael@0:   {
michael@0:     if (unlikely (this->ran_out_of_room || this->end - this->head < ptrdiff_t (size))) {
michael@0:       this->ran_out_of_room = true;
michael@0:       return NULL;
michael@0:     }
michael@0:     memset (this->head, 0, size);
michael@0:     char *ret = this->head;
michael@0:     this->head += size;
michael@0:     return reinterpret_cast<Type *> (ret);
michael@0:   }
michael@0: 
michael@0:   template <typename Type>
michael@0:   inline Type *allocate_min (void)
michael@0:   {
michael@0:     return this->allocate_size<Type> (Type::min_size);
michael@0:   }
michael@0: 
michael@0:   template <typename Type>
michael@0:   inline Type *start_embed (void)
michael@0:   {
michael@0:     Type *ret = reinterpret_cast<Type *> (this->head);
michael@0:     return ret;
michael@0:   }
michael@0: 
michael@0:   template <typename Type>
michael@0:   inline Type *embed (const Type &obj)
michael@0:   {
michael@0:     unsigned int size = obj.get_size ();
michael@0:     Type *ret = this->allocate_size<Type> (size);
michael@0:     if (unlikely (!ret)) return NULL;
michael@0:     memcpy (ret, obj, size);
michael@0:     return ret;
michael@0:   }
michael@0: 
michael@0:   template <typename Type>
michael@0:   inline Type *extend_min (Type &obj)
michael@0:   {
michael@0:     unsigned int size = obj.min_size;
michael@0:     assert (this->start <= (char *) &obj && (char *) &obj <= this->head && (char *) &obj + size >= this->head);
michael@0:     if (unlikely (!this->allocate_size<Type> (((char *) &obj) + size - this->head))) return NULL;
michael@0:     return reinterpret_cast<Type *> (&obj);
michael@0:   }
michael@0: 
michael@0:   template <typename Type>
michael@0:   inline Type *extend (Type &obj)
michael@0:   {
michael@0:     unsigned int size = obj.get_size ();
michael@0:     assert (this->start < (char *) &obj && (char *) &obj <= this->head && (char *) &obj + size >= this->head);
michael@0:     if (unlikely (!this->allocate_size<Type> (((char *) &obj) + size - this->head))) return NULL;
michael@0:     return reinterpret_cast<Type *> (&obj);
michael@0:   }
michael@0: 
michael@0:   inline void truncate (void *head)
michael@0:   {
michael@0:     assert (this->start < head && head <= this->head);
michael@0:     this->head = (char *) head;
michael@0:   }
michael@0: 
michael@0:   unsigned int debug_depth;
michael@0:   char *start, *end, *head;
michael@0:   bool ran_out_of_room;
michael@0: };
michael@0: 
michael@0: template <typename Type>
michael@0: struct Supplier
michael@0: {
michael@0:   inline Supplier (const Type *array, unsigned int len_)
michael@0:   {
michael@0:     head = array;
michael@0:     len = len_;
michael@0:   }
michael@0:   inline const Type operator [] (unsigned int i) const
michael@0:   {
michael@0:     if (unlikely (i >= len)) return Type ();
michael@0:     return head[i];
michael@0:   }
michael@0: 
michael@0:   inline void advance (unsigned int count)
michael@0:   {
michael@0:     if (unlikely (count > len))
michael@0:       count = len;
michael@0:     len -= count;
michael@0:     head += count;
michael@0:   }
michael@0: 
michael@0:   private:
michael@0:   inline Supplier (const Supplier<Type> &); /* Disallow copy */
michael@0:   inline Supplier<Type>& operator= (const Supplier<Type> &); /* Disallow copy */
michael@0: 
michael@0:   unsigned int len;
michael@0:   const Type *head;
michael@0: };
michael@0: 
michael@0: 
michael@0: 
michael@0: 
michael@0: /*
michael@0:  *
michael@0:  * The OpenType Font File: Data Types
michael@0:  */
michael@0: 
michael@0: 
michael@0: /* "The following data types are used in the OpenType font file.
michael@0:  *  All OpenType fonts use Motorola-style byte ordering (Big Endian):" */
michael@0: 
michael@0: /*
michael@0:  * Int types
michael@0:  */
michael@0: 
michael@0: 
michael@0: template <typename Type, int Bytes> struct BEInt;
michael@0: 
michael@0: template <typename Type>
michael@0: struct BEInt<Type, 2>
michael@0: {
michael@0:   public:
michael@0:   inline void set (Type i) { hb_be_uint16_put (v,i); }
michael@0:   inline operator Type (void) const { return hb_be_uint16_get (v); }
michael@0:   inline bool operator == (const BEInt<Type, 2>& o) const { return hb_be_uint16_eq (v, o.v); }
michael@0:   inline bool operator != (const BEInt<Type, 2>& o) const { return !(*this == o); }
michael@0:   private: uint8_t v[2];
michael@0: };
michael@0: template <typename Type>
michael@0: struct BEInt<Type, 4>
michael@0: {
michael@0:   public:
michael@0:   inline void set (Type i) { hb_be_uint32_put (v,i); }
michael@0:   inline operator Type (void) const { return hb_be_uint32_get (v); }
michael@0:   inline bool operator == (const BEInt<Type, 4>& o) const { return hb_be_uint32_eq (v, o.v); }
michael@0:   inline bool operator != (const BEInt<Type, 4>& o) const { return !(*this == o); }
michael@0:   private: uint8_t v[4];
michael@0: };
michael@0: template <typename Type>
michael@0: struct BEInt<Type, 3>
michael@0: {
michael@0:   public:
michael@0:   inline void set (Type i) { hb_be_uint24_put (v,i); }
michael@0:   inline operator Type (void) const { return hb_be_uint24_get (v); }
michael@0:   inline bool operator == (const BEInt<Type, 3>& o) const { return hb_be_uint24_eq (v, o.v); }
michael@0:   inline bool operator != (const BEInt<Type, 3>& o) const { return !(*this == o); }
michael@0:   private: uint8_t v[3];
michael@0: };
michael@0: 
michael@0: /* Integer types in big-endian order and no alignment requirement */
michael@0: template <typename Type, unsigned int Size>
michael@0: struct IntType
michael@0: {
michael@0:   inline void set (Type i) { v.set (i); }
michael@0:   inline operator Type(void) const { return v; }
michael@0:   inline bool operator == (const IntType<Type,Size> &o) const { return v == o.v; }
michael@0:   inline bool operator != (const IntType<Type,Size> &o) const { return v != o.v; }
michael@0:   static inline int cmp (const IntType<Type,Size> *a, const IntType<Type,Size> *b) { return b->cmp (*a); }
michael@0:   inline int cmp (IntType<Type,Size> va) const { Type a = va; Type b = v; return a < b ? -1 : a == b ? 0 : +1; }
michael@0:   inline int cmp (Type a) const { Type b = v; return a < b ? -1 : a == b ? 0 : +1; }
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (likely (c->check_struct (this)));
michael@0:   }
michael@0:   protected:
michael@0:   BEInt<Type, Size> v;
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (Size);
michael@0: };
michael@0: 
michael@0: typedef IntType<uint16_t, 2> USHORT;	/* 16-bit unsigned integer. */
michael@0: typedef IntType<int16_t,  2> SHORT;	/* 16-bit signed integer. */
michael@0: typedef IntType<uint32_t, 4> ULONG;	/* 32-bit unsigned integer. */
michael@0: typedef IntType<int32_t,  4> LONG;	/* 32-bit signed integer. */
michael@0: typedef IntType<uint32_t, 3> UINT24;	/* 24-bit unsigned integer. */
michael@0: 
michael@0: /* 16-bit signed integer (SHORT) that describes a quantity in FUnits. */
michael@0: typedef SHORT FWORD;
michael@0: 
michael@0: /* 16-bit unsigned integer (USHORT) that describes a quantity in FUnits. */
michael@0: typedef USHORT UFWORD;
michael@0: 
michael@0: /* Date represented in number of seconds since 12:00 midnight, January 1,
michael@0:  * 1904. The value is represented as a signed 64-bit integer. */
michael@0: struct LONGDATETIME
michael@0: {
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (likely (c->check_struct (this)));
michael@0:   }
michael@0:   protected:
michael@0:   LONG major;
michael@0:   ULONG minor;
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (8);
michael@0: };
michael@0: 
michael@0: /* Array of four uint8s (length = 32 bits) used to identify a script, language
michael@0:  * system, feature, or baseline */
michael@0: struct Tag : ULONG
michael@0: {
michael@0:   /* What the char* converters return is NOT nul-terminated.  Print using "%.4s" */
michael@0:   inline operator const char* (void) const { return reinterpret_cast<const char *> (&this->v); }
michael@0:   inline operator char* (void) { return reinterpret_cast<char *> (&this->v); }
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (4);
michael@0: };
michael@0: DEFINE_NULL_DATA (Tag, "    ");
michael@0: 
michael@0: /* Glyph index number, same as uint16 (length = 16 bits) */
michael@0: typedef USHORT GlyphID;
michael@0: 
michael@0: /* Script/language-system/feature index */
michael@0: struct Index : USHORT {
michael@0:   static const unsigned int NOT_FOUND_INDEX = 0xFFFF;
michael@0: };
michael@0: DEFINE_NULL_DATA (Index, "\xff\xff");
michael@0: 
michael@0: /* Offset to a table, same as uint16 (length = 16 bits), Null offset = 0x0000 */
michael@0: struct Offset : USHORT
michael@0: {
michael@0:   inline bool is_null (void) const { return 0 == *this; }
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (2);
michael@0: };
michael@0: 
michael@0: /* LongOffset to a table, same as uint32 (length = 32 bits), Null offset = 0x00000000 */
michael@0: struct LongOffset : ULONG
michael@0: {
michael@0:   inline bool is_null (void) const { return 0 == *this; }
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (4);
michael@0: };
michael@0: 
michael@0: 
michael@0: /* CheckSum */
michael@0: struct CheckSum : ULONG
michael@0: {
michael@0:   /* This is reference implementation from the spec. */
michael@0:   static inline uint32_t CalcTableChecksum (const ULONG *Table, uint32_t Length)
michael@0:   {
michael@0:     uint32_t Sum = 0L;
michael@0:     const ULONG *EndPtr = Table+((Length+3) & ~3) / ULONG::static_size;
michael@0: 
michael@0:     while (Table < EndPtr)
michael@0:       Sum += *Table++;
michael@0:     return Sum;
michael@0:   }
michael@0: 
michael@0:   /* Note: data should be 4byte aligned and have 4byte padding at the end. */
michael@0:   inline void set_for_data (const void *data, unsigned int length)
michael@0:   { set (CalcTableChecksum ((const ULONG *) data, length)); }
michael@0: 
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (4);
michael@0: };
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * Version Numbers
michael@0:  */
michael@0: 
michael@0: struct FixedVersion
michael@0: {
michael@0:   inline uint32_t to_int (void) const { return (major << 16) + minor; }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (c->check_struct (this));
michael@0:   }
michael@0: 
michael@0:   USHORT major;
michael@0:   USHORT minor;
michael@0:   public:
michael@0:   DEFINE_SIZE_STATIC (4);
michael@0: };
michael@0: 
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * Template subclasses of Offset and LongOffset that do the dereferencing.
michael@0:  * Use: (base+offset)
michael@0:  */
michael@0: 
michael@0: template <typename OffsetType, typename Type>
michael@0: struct GenericOffsetTo : OffsetType
michael@0: {
michael@0:   inline const Type& operator () (const void *base) const
michael@0:   {
michael@0:     unsigned int offset = *this;
michael@0:     if (unlikely (!offset)) return Null(Type);
michael@0:     return StructAtOffset<Type> (base, offset);
michael@0:   }
michael@0: 
michael@0:   inline Type& serialize (hb_serialize_context_t *c, void *base)
michael@0:   {
michael@0:     Type *t = c->start_embed<Type> ();
michael@0:     this->set ((char *) t - (char *) base); /* TODO(serialize) Overflow? */
michael@0:     return *t;
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c, void *base) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (unlikely (!c->check_struct (this))) return TRACE_RETURN (false);
michael@0:     unsigned int offset = *this;
michael@0:     if (unlikely (!offset)) return TRACE_RETURN (true);
michael@0:     Type &obj = StructAtOffset<Type> (base, offset);
michael@0:     return TRACE_RETURN (likely (obj.sanitize (c)) || neuter (c));
michael@0:   }
michael@0:   template <typename T>
michael@0:   inline bool sanitize (hb_sanitize_context_t *c, void *base, T user_data) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (unlikely (!c->check_struct (this))) return TRACE_RETURN (false);
michael@0:     unsigned int offset = *this;
michael@0:     if (unlikely (!offset)) return TRACE_RETURN (true);
michael@0:     Type &obj = StructAtOffset<Type> (base, offset);
michael@0:     return TRACE_RETURN (likely (obj.sanitize (c, user_data)) || neuter (c));
michael@0:   }
michael@0: 
michael@0:   inline bool try_set (hb_sanitize_context_t *c, const OffsetType &v) {
michael@0:     if (c->may_edit (this, this->static_size)) {
michael@0:       this->set (v);
michael@0:       return true;
michael@0:     }
michael@0:     return false;
michael@0:   }
michael@0:   /* Set the offset to Null */
michael@0:   inline bool neuter (hb_sanitize_context_t *c) {
michael@0:     if (c->may_edit (this, this->static_size)) {
michael@0:       this->set (0); /* 0 is Null offset */
michael@0:       return true;
michael@0:     }
michael@0:     return false;
michael@0:   }
michael@0: };
michael@0: template <typename Base, typename OffsetType, typename Type>
michael@0: inline const Type& operator + (const Base &base, const GenericOffsetTo<OffsetType, Type> &offset) { return offset (base); }
michael@0: template <typename Base, typename OffsetType, typename Type>
michael@0: inline Type& operator + (Base &base, GenericOffsetTo<OffsetType, Type> &offset) { return offset (base); }
michael@0: 
michael@0: template <typename Type>
michael@0: struct OffsetTo : GenericOffsetTo<Offset, Type> {};
michael@0: 
michael@0: template <typename Type>
michael@0: struct LongOffsetTo : GenericOffsetTo<LongOffset, Type> {};
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * Array Types
michael@0:  */
michael@0: 
michael@0: template <typename LenType, typename Type>
michael@0: struct GenericArrayOf
michael@0: {
michael@0:   const Type *sub_array (unsigned int start_offset, unsigned int *pcount /* IN/OUT */) const
michael@0:   {
michael@0:     unsigned int count = len;
michael@0:     if (unlikely (start_offset > count))
michael@0:       count = 0;
michael@0:     else
michael@0:       count -= start_offset;
michael@0:     count = MIN (count, *pcount);
michael@0:     *pcount = count;
michael@0:     return array + start_offset;
michael@0:   }
michael@0: 
michael@0:   inline const Type& operator [] (unsigned int i) const
michael@0:   {
michael@0:     if (unlikely (i >= len)) return Null(Type);
michael@0:     return array[i];
michael@0:   }
michael@0:   inline Type& operator [] (unsigned int i)
michael@0:   {
michael@0:     return array[i];
michael@0:   }
michael@0:   inline unsigned int get_size (void) const
michael@0:   { return len.static_size + len * Type::static_size; }
michael@0: 
michael@0:   inline bool serialize (hb_serialize_context_t *c,
michael@0: 			 unsigned int items_len)
michael@0:   {
michael@0:     TRACE_SERIALIZE (this);
michael@0:     if (unlikely (!c->extend_min (*this))) return TRACE_RETURN (false);
michael@0:     len.set (items_len); /* TODO(serialize) Overflow? */
michael@0:     if (unlikely (!c->extend (*this))) return TRACE_RETURN (false);
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: 
michael@0:   inline bool serialize (hb_serialize_context_t *c,
michael@0: 			 Supplier<Type> &items,
michael@0: 			 unsigned int items_len)
michael@0:   {
michael@0:     TRACE_SERIALIZE (this);
michael@0:     if (unlikely (!serialize (c, items_len))) return TRACE_RETURN (false);
michael@0:     for (unsigned int i = 0; i < items_len; i++)
michael@0:       array[i] = items[i];
michael@0:     items.advance (items_len);
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (unlikely (!sanitize_shallow (c))) return TRACE_RETURN (false);
michael@0: 
michael@0:     /* Note: for structs that do not reference other structs,
michael@0:      * we do not need to call their sanitize() as we already did
michael@0:      * a bound check on the aggregate array size.  We just include
michael@0:      * a small unreachable expression to make sure the structs
michael@0:      * pointed to do have a simple sanitize(), ie. they do not
michael@0:      * reference other structs via offsets.
michael@0:      */
michael@0:     (void) (false && array[0].sanitize (c));
michael@0: 
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0:   inline bool sanitize (hb_sanitize_context_t *c, void *base) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (unlikely (!sanitize_shallow (c))) return TRACE_RETURN (false);
michael@0:     unsigned int count = len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:       if (unlikely (!array[i].sanitize (c, base)))
michael@0:         return TRACE_RETURN (false);
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0:   template <typename T>
michael@0:   inline bool sanitize (hb_sanitize_context_t *c, void *base, T user_data) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (unlikely (!sanitize_shallow (c))) return TRACE_RETURN (false);
michael@0:     unsigned int count = len;
michael@0:     for (unsigned int i = 0; i < count; i++)
michael@0:       if (unlikely (!array[i].sanitize (c, base, user_data)))
michael@0:         return TRACE_RETURN (false);
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: 
michael@0:   private:
michael@0:   inline bool sanitize_shallow (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (c->check_struct (this) && c->check_array (this, Type::static_size, len));
michael@0:   }
michael@0: 
michael@0:   public:
michael@0:   LenType len;
michael@0:   Type array[VAR];
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (sizeof (LenType), array);
michael@0: };
michael@0: 
michael@0: /* An array with a USHORT number of elements. */
michael@0: template <typename Type>
michael@0: struct ArrayOf : GenericArrayOf<USHORT, Type> {};
michael@0: 
michael@0: /* An array with a ULONG number of elements. */
michael@0: template <typename Type>
michael@0: struct LongArrayOf : GenericArrayOf<ULONG, Type> {};
michael@0: 
michael@0: /* Array of Offset's */
michael@0: template <typename Type>
michael@0: struct OffsetArrayOf : ArrayOf<OffsetTo<Type> > {};
michael@0: 
michael@0: /* Array of LongOffset's */
michael@0: template <typename Type>
michael@0: struct LongOffsetArrayOf : ArrayOf<LongOffsetTo<Type> > {};
michael@0: 
michael@0: /* LongArray of LongOffset's */
michael@0: template <typename Type>
michael@0: struct LongOffsetLongArrayOf : LongArrayOf<LongOffsetTo<Type> > {};
michael@0: 
michael@0: /* Array of offsets relative to the beginning of the array itself. */
michael@0: template <typename Type>
michael@0: struct OffsetListOf : OffsetArrayOf<Type>
michael@0: {
michael@0:   inline const Type& operator [] (unsigned int i) const
michael@0:   {
michael@0:     if (unlikely (i >= this->len)) return Null(Type);
michael@0:     return this+this->array[i];
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (OffsetArrayOf<Type>::sanitize (c, this));
michael@0:   }
michael@0:   template <typename T>
michael@0:   inline bool sanitize (hb_sanitize_context_t *c, T user_data) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     return TRACE_RETURN (OffsetArrayOf<Type>::sanitize (c, this, user_data));
michael@0:   }
michael@0: };
michael@0: 
michael@0: 
michael@0: /* An array with a USHORT number of elements,
michael@0:  * starting at second element. */
michael@0: template <typename Type>
michael@0: struct HeadlessArrayOf
michael@0: {
michael@0:   inline const Type& operator [] (unsigned int i) const
michael@0:   {
michael@0:     if (unlikely (i >= len || !i)) return Null(Type);
michael@0:     return array[i-1];
michael@0:   }
michael@0:   inline unsigned int get_size (void) const
michael@0:   { return len.static_size + (len ? len - 1 : 0) * Type::static_size; }
michael@0: 
michael@0:   inline bool serialize (hb_serialize_context_t *c,
michael@0: 			 Supplier<Type> &items,
michael@0: 			 unsigned int items_len)
michael@0:   {
michael@0:     TRACE_SERIALIZE (this);
michael@0:     if (unlikely (!c->extend_min (*this))) return TRACE_RETURN (false);
michael@0:     len.set (items_len); /* TODO(serialize) Overflow? */
michael@0:     if (unlikely (!items_len)) return TRACE_RETURN (true);
michael@0:     if (unlikely (!c->extend (*this))) return TRACE_RETURN (false);
michael@0:     for (unsigned int i = 0; i < items_len - 1; i++)
michael@0:       array[i] = items[i];
michael@0:     items.advance (items_len - 1);
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize_shallow (hb_sanitize_context_t *c) {
michael@0:     return c->check_struct (this)
michael@0: 	&& c->check_array (this, Type::static_size, len);
michael@0:   }
michael@0: 
michael@0:   inline bool sanitize (hb_sanitize_context_t *c) {
michael@0:     TRACE_SANITIZE (this);
michael@0:     if (unlikely (!sanitize_shallow (c))) return TRACE_RETURN (false);
michael@0: 
michael@0:     /* Note: for structs that do not reference other structs,
michael@0:      * we do not need to call their sanitize() as we already did
michael@0:      * a bound check on the aggregate array size.  We just include
michael@0:      * a small unreachable expression to make sure the structs
michael@0:      * pointed to do have a simple sanitize(), ie. they do not
michael@0:      * reference other structs via offsets.
michael@0:      */
michael@0:     (void) (false && array[0].sanitize (c));
michael@0: 
michael@0:     return TRACE_RETURN (true);
michael@0:   }
michael@0: 
michael@0:   USHORT len;
michael@0:   Type array[VAR];
michael@0:   public:
michael@0:   DEFINE_SIZE_ARRAY (sizeof (USHORT), array);
michael@0: };
michael@0: 
michael@0: 
michael@0: /* An array with sorted elements.  Supports binary searching. */
michael@0: template <typename Type>
michael@0: struct SortedArrayOf : ArrayOf<Type> {
michael@0: 
michael@0:   template <typename SearchType>
michael@0:   inline int search (const SearchType &x) const
michael@0:   {
michael@0:     /* Hand-coded bsearch here since this is in the hot inner loop. */
michael@0:     int min = 0, max = (int) this->len - 1;
michael@0:     while (min <= max)
michael@0:     {
michael@0:       int mid = (min + max) / 2;
michael@0:       int c = this->array[mid].cmp (x);
michael@0:       if (c < 0)
michael@0:         max = mid - 1;
michael@0:       else if (c > 0)
michael@0:         min = mid + 1;
michael@0:       else
michael@0:         return mid;
michael@0:     }
michael@0:     return -1;
michael@0:   }
michael@0: };
michael@0: 
michael@0: 
michael@0: } /* namespace OT */
michael@0: 
michael@0: 
michael@0: #endif /* HB_OPEN_TYPE_PRIVATE_HH */