/* * Copyright © 2018 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. * * Google Author(s): Behdad Esfahbod */ #ifndef HB_ARRAY_HH #define HB_ARRAY_HH #include "hb.hh" #include "hb-algs.hh" #include "hb-iter.hh" #include "hb-null.hh" template <typename Type> struct hb_sorted_array_t; enum hb_not_found_t { HB_NOT_FOUND_DONT_STORE, HB_NOT_FOUND_STORE, HB_NOT_FOUND_STORE_CLOSEST, }; template <typename Type> struct hb_array_t : hb_iter_with_fallback_t<hb_array_t<Type>, Type&> { /* * Constructors. */ hb_array_t () = default; hb_array_t (const hb_array_t&) = default; ~hb_array_t () = default; hb_array_t& operator= (const hb_array_t&) = default; hb_array_t& operator= (hb_array_t&&) = default; constexpr hb_array_t (Type *array_, unsigned int length_) : arrayZ (array_), length (length_) {} template <unsigned int length_> constexpr hb_array_t (Type (&array_)[length_]) : hb_array_t (array_, length_) {} template <typename U, hb_enable_if (hb_is_cr_convertible(U, Type))> constexpr hb_array_t (const hb_array_t<U> &o) : hb_iter_with_fallback_t<hb_array_t, Type&> (), arrayZ (o.arrayZ), length (o.length), backwards_length (o.backwards_length) {} template <typename U, hb_enable_if (hb_is_cr_convertible(U, Type))> hb_array_t& operator = (const hb_array_t<U> &o) { arrayZ = o.arrayZ; length = o.length; backwards_length = o.backwards_length; return *this; } /* * Iterator implementation. */ typedef Type& __item_t__; static constexpr bool is_random_access_iterator = true; Type& __item_at__ (unsigned i) const { if (unlikely (i >= length)) return CrapOrNull (Type); return arrayZ[i]; } void __forward__ (unsigned n) { if (unlikely (n > length)) n = length; length -= n; backwards_length += n; arrayZ += n; } void __rewind__ (unsigned n) { if (unlikely (n > backwards_length)) n = backwards_length; length += n; backwards_length -= n; arrayZ -= n; } unsigned __len__ () const { return length; } /* Ouch. The operator== compares the contents of the array. For range-based for loops, * it's best if we can just compare arrayZ, though comparing contents is still fast, * but also would require that Type has operator==. As such, we optimize this operator * for range-based for loop and just compare arrayZ and length. */ bool operator != (const hb_array_t& o) const { return this->arrayZ != o.arrayZ || this->length != o.length; } /* Extra operators. */ Type * operator & () const { return arrayZ; } operator hb_array_t<const Type> () { return hb_array_t<const Type> (arrayZ, length); } template <typename T> operator T * () const { return arrayZ; } HB_INTERNAL bool operator == (const hb_array_t &o) const; uint32_t hash () const { uint32_t current = 0; for (unsigned int i = 0; i < this->length; i++) { current = current * 31 + hb_hash (this->arrayZ[i]); } return current; } /* * Compare, Sort, and Search. */ /* Note: our compare is NOT lexicographic; it also does NOT call Type::cmp. */ int cmp (const hb_array_t &a) const { if (length != a.length) return (int) a.length - (int) length; return hb_memcmp (a.arrayZ, arrayZ, get_size ()); } HB_INTERNAL static int cmp (const void *pa, const void *pb) { hb_array_t *a = (hb_array_t *) pa; hb_array_t *b = (hb_array_t *) pb; return b->cmp (*a); } template <typename T> Type *lsearch (const T &x, Type *not_found = nullptr) { unsigned i; return lfind (x, &i) ? &this->arrayZ[i] : not_found; } template <typename T> const Type *lsearch (const T &x, const Type *not_found = nullptr) const { unsigned i; return lfind (x, &i) ? &this->arrayZ[i] : not_found; } template <typename T> bool lfind (const T &x, unsigned *pos = nullptr, hb_not_found_t not_found = HB_NOT_FOUND_DONT_STORE, unsigned int to_store = (unsigned int) -1) const { for (unsigned i = 0; i < length; ++i) if (hb_equal (x, this->arrayZ[i])) { if (pos) *pos = i; return true; } if (pos) { switch (not_found) { case HB_NOT_FOUND_DONT_STORE: break; case HB_NOT_FOUND_STORE: *pos = to_store; break; case HB_NOT_FOUND_STORE_CLOSEST: *pos = length; break; } } return false; } hb_sorted_array_t<Type> qsort (int (*cmp_)(const void*, const void*)) { if (likely (length)) hb_qsort (arrayZ, length, this->get_item_size (), cmp_); return hb_sorted_array_t<Type> (*this); } hb_sorted_array_t<Type> qsort () { if (likely (length)) hb_qsort (arrayZ, length, this->get_item_size (), Type::cmp); return hb_sorted_array_t<Type> (*this); } void qsort (unsigned int start, unsigned int end) { end = hb_min (end, length); assert (start <= end); if (likely (start < end)) hb_qsort (arrayZ + start, end - start, this->get_item_size (), Type::cmp); } /* * Other methods. */ unsigned int get_size () const { return length * this->get_item_size (); } /* * Reverse the order of items in this array in the range [start, end). */ void reverse (unsigned start = 0, unsigned end = -1) { start = hb_min (start, length); end = hb_min (end, length); if (end < start + 2) return; for (unsigned lhs = start, rhs = end - 1; lhs < rhs; lhs++, rhs--) hb_swap (arrayZ[rhs], arrayZ[lhs]); } hb_array_t sub_array (unsigned int start_offset = 0, unsigned int *seg_count = nullptr /* IN/OUT */) const { if (!start_offset && !seg_count) return *this; unsigned int count = length; if (unlikely (start_offset > count)) count = 0; else count -= start_offset; if (seg_count) count = *seg_count = hb_min (count, *seg_count); return hb_array_t (arrayZ + start_offset, count); } hb_array_t sub_array (unsigned int start_offset, unsigned int seg_count) const { return sub_array (start_offset, &seg_count); } hb_array_t truncate (unsigned length) const { return sub_array (0, length); } template <typename T, unsigned P = sizeof (Type), hb_enable_if (P == 1)> const T *as () const { return length < hb_min_size (T) ? &Null (T) : reinterpret_cast<const T *> (arrayZ); } template <typename T, unsigned P = sizeof (Type), hb_enable_if (P == 1)> bool check_range (const T *p, unsigned int size = T::static_size) const { return arrayZ <= ((const char *) p) && ((const char *) p) <= arrayZ + length && (unsigned int) (arrayZ + length - (const char *) p) >= size; } /* Only call if you allocated the underlying array using hb_malloc() or similar. */ void fini () { hb_free ((void *) arrayZ); arrayZ = nullptr; length = 0; } template <typename hb_serialize_context_t> hb_array_t copy (hb_serialize_context_t *c) const { TRACE_SERIALIZE (this); auto* out = c->start_embed (arrayZ); if (unlikely (!c->extend_size (out, get_size ()))) return_trace (hb_array_t ()); for (unsigned i = 0; i < length; i++) out[i] = arrayZ[i]; /* TODO: add version that calls c->copy() */ return_trace (hb_array_t (out, length)); } template <typename hb_sanitize_context_t> bool sanitize (hb_sanitize_context_t *c) const { return c->check_array (arrayZ, length); } /* * Members */ public: Type *arrayZ = nullptr; unsigned int length = 0; unsigned int backwards_length = 0; }; template <typename T> inline hb_array_t<T> hb_array (T *array, unsigned int length) { return hb_array_t<T> (array, length); } template <typename T, unsigned int length_> inline hb_array_t<T> hb_array (T (&array_)[length_]) { return hb_array_t<T> (array_); } template <typename Type> struct hb_sorted_array_t : hb_iter_t<hb_sorted_array_t<Type>, Type&>, hb_array_t<Type> { typedef hb_iter_t<hb_sorted_array_t, Type&> iter_base_t; HB_ITER_USING (iter_base_t); static constexpr bool is_random_access_iterator = true; static constexpr bool is_sorted_iterator = true; hb_sorted_array_t () = default; hb_sorted_array_t (const hb_sorted_array_t&) = default; ~hb_sorted_array_t () = default; hb_sorted_array_t& operator= (const hb_sorted_array_t&) = default; hb_sorted_array_t& operator= (hb_sorted_array_t&&) = default; constexpr hb_sorted_array_t (Type *array_, unsigned int length_) : hb_array_t<Type> (array_, length_) {} template <unsigned int length_> constexpr hb_sorted_array_t (Type (&array_)[length_]) : hb_array_t<Type> (array_) {} template <typename U, hb_enable_if (hb_is_cr_convertible(U, Type))> constexpr hb_sorted_array_t (const hb_array_t<U> &o) : hb_iter_t<hb_sorted_array_t, Type&> (), hb_array_t<Type> (o) {} template <typename U, hb_enable_if (hb_is_cr_convertible(U, Type))> hb_sorted_array_t& operator = (const hb_array_t<U> &o) { hb_array_t<Type> (*this) = o; return *this; } /* Iterator implementation. */ /* See comment in hb_array_of::operator != */ bool operator != (const hb_sorted_array_t& o) const { return this->arrayZ != o.arrayZ || this->length != o.length; } hb_sorted_array_t sub_array (unsigned int start_offset, unsigned int *seg_count /* IN/OUT */) const { return hb_sorted_array_t (((const hb_array_t<Type> *) (this))->sub_array (start_offset, seg_count)); } hb_sorted_array_t sub_array (unsigned int start_offset, unsigned int seg_count) const { return sub_array (start_offset, &seg_count); } hb_sorted_array_t truncate (unsigned length) const { return sub_array (0, length); } template <typename T> Type *bsearch (const T &x, Type *not_found = nullptr) { unsigned int i; return bfind (x, &i) ? &this->arrayZ[i] : not_found; } template <typename T, typename ...Ts> const Type *bsearch (const T &x, const Type *not_found = nullptr) const { unsigned int i; return bfind (x, &i) ? &this->arrayZ[i] : not_found; } template <typename T> bool bfind (const T &x, unsigned int *i = nullptr, hb_not_found_t not_found = HB_NOT_FOUND_DONT_STORE, unsigned int to_store = (unsigned int) -1) const { unsigned pos; if (bsearch_impl (x, &pos)) { if (i) *i = pos; return true; } if (i) { switch (not_found) { case HB_NOT_FOUND_DONT_STORE: break; case HB_NOT_FOUND_STORE: *i = to_store; break; case HB_NOT_FOUND_STORE_CLOSEST: *i = pos; break; } } return false; } template <typename T, typename ...Ts> bool bsearch_impl (const T &x, unsigned *pos, Ts... ds) const { return hb_bsearch_impl (pos, x, this->arrayZ, this->length, sizeof (Type), _hb_cmp_method<T, Type, Ts...>, ds...); } }; template <typename T> inline hb_sorted_array_t<T> hb_sorted_array (T *array, unsigned int length) { return hb_sorted_array_t<T> (array, length); } template <typename T, unsigned int length_> inline hb_sorted_array_t<T> hb_sorted_array (T (&array_)[length_]) { return hb_sorted_array_t<T> (array_); } template <typename T> inline bool hb_array_t<T>::operator == (const hb_array_t<T> &o) const { if (o.length != this->length) return false; for (unsigned int i = 0; i < this->length; i++) { if (this->arrayZ[i] != o.arrayZ[i]) return false; } return true; } template <> inline bool hb_array_t<const char>::operator == (const hb_array_t<const char> &o) const { if (o.length != this->length) return false; return 0 == hb_memcmp (arrayZ, o.arrayZ, length); } template <> inline bool hb_array_t<const unsigned char>::operator == (const hb_array_t<const unsigned char> &o) const { if (o.length != this->length) return false; return 0 == hb_memcmp (arrayZ, o.arrayZ, length); } template <> inline uint32_t hb_array_t<const char>::hash () const { uint32_t current = 0; for (unsigned int i = 0; i < this->length; i++) current = current * 31 + (uint32_t) (this->arrayZ[i] * 2654435761u); return current; } template <> inline uint32_t hb_array_t<const unsigned char>::hash () const { uint32_t current = 0; for (unsigned int i = 0; i < this->length; i++) current = current * 31 + (uint32_t) (this->arrayZ[i] * 2654435761u); return current; } typedef hb_array_t<const char> hb_bytes_t; typedef hb_array_t<const unsigned char> hb_ubytes_t; #endif /* HB_ARRAY_HH */