1 /* 2 * Copyright 2018 Google, Inc. 3 * 4 * This is part of HarfBuzz, a text shaping library. 5 * 6 * Permission is hereby granted, without written agreement and without 7 * license or royalty fees, to use, copy, modify, and distribute this 8 * software and its documentation for any purpose, provided that the 9 * above copyright notice and the following two paragraphs appear in 10 * all copies of this software. 11 * 12 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR 13 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES 14 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN 15 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH 16 * DAMAGE. 17 * 18 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, 19 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 20 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS 21 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO 22 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. 23 * 24 * Google Author(s): Behdad Esfahbod 25 */ 26 27 #ifndef HB_ARRAY_HH 28 #define HB_ARRAY_HH 29 30 #include "hb.hh" 31 32 33 template <typename Type> 34 struct hb_sorted_array_t; 35 36 template <typename Type> 37 struct hb_array_t 38 { 39 typedef Type ItemType; 40 enum { item_size = hb_static_size (Type) }; 41 42 /* 43 * Constructors. 44 */ 45 hb_array_t () : arrayZ (nullptr), len (0) {} 46 hb_array_t (const hb_array_t &o) : arrayZ (o.arrayZ), len (o.len) {} 47 hb_array_t (Type *array_, unsigned int len_) : arrayZ (array_), len (len_) {} 48 template <unsigned int len_> hb_array_t (Type (&array_)[len_]) : arrayZ (array_), len (len_) {} 49 50 /* 51 * Operators. 52 */ 53 54 Type& operator [] (int i_) const 55 { 56 unsigned int i = (unsigned int) i_; 57 if (unlikely (i >= len)) return CrapOrNull(Type); 58 return arrayZ[i]; 59 } 60 61 explicit_operator bool () const { return len; } 62 Type * operator & () const { return arrayZ; } 63 Type & operator * () { return (this->operator [])[0]; } 64 operator hb_array_t<const Type> () { return hb_array_t<const Type> (arrayZ, len); } 65 template <typename T> operator T * () const { return arrayZ; } 66 67 hb_array_t<Type> & operator += (unsigned int count) 68 { 69 if (unlikely (count > len)) 70 count = len; 71 len -= count; 72 arrayZ += count; 73 return *this; 74 } 75 hb_array_t<Type> & operator -= (unsigned int count) 76 { 77 if (unlikely (count > len)) 78 count = len; 79 len -= count; 80 return *this; 81 } 82 hb_array_t<Type> & operator ++ () { *this += 1; } 83 hb_array_t<Type> & operator -- () { *this -= 1; } 84 hb_array_t<Type> operator + (unsigned int count) 85 { hb_array_t<Type> copy (*this); *this += count; return copy; } 86 hb_array_t<Type> operator - (unsigned int count) 87 { hb_array_t<Type> copy (*this); *this -= count; return copy; } 88 hb_array_t<Type> operator ++ (int) 89 { hb_array_t<Type> copy (*this); ++*this; return copy; } 90 hb_array_t<Type> operator -- (int) 91 { hb_array_t<Type> copy (*this); --*this; return copy; } 92 93 /* 94 * Compare, Sort, and Search. 95 */ 96 97 /* Note: our compare is NOT lexicographic; it also does NOT call Type::cmp. */ 98 int cmp (const hb_array_t<Type> &a) const 99 { 100 if (len != a.len) 101 return (int) a.len - (int) len; 102 return hb_memcmp (a.arrayZ, arrayZ, get_size ()); 103 } 104 static int cmp (const void *pa, const void *pb) 105 { 106 hb_array_t<Type> *a = (hb_array_t<Type> *) pa; 107 hb_array_t<Type> *b = (hb_array_t<Type> *) pb; 108 return b->cmp (*a); 109 } 110 111 template <typename T> 112 Type *lsearch (const T &x, Type *not_found = nullptr) 113 { 114 unsigned int count = len; 115 for (unsigned int i = 0; i < count; i++) 116 if (!this->arrayZ[i].cmp (x)) 117 return &this->arrayZ[i]; 118 return not_found; 119 } 120 template <typename T> 121 const Type *lsearch (const T &x, const Type *not_found = nullptr) const 122 { 123 unsigned int count = len; 124 for (unsigned int i = 0; i < count; i++) 125 if (!this->arrayZ[i].cmp (x)) 126 return &this->arrayZ[i]; 127 return not_found; 128 } 129 130 hb_sorted_array_t<Type> qsort (int (*cmp_)(const void*, const void*)) 131 { 132 ::qsort (arrayZ, len, item_size, cmp_); 133 return hb_sorted_array_t<Type> (*this); 134 } 135 hb_sorted_array_t<Type> qsort () 136 { 137 ::qsort (arrayZ, len, item_size, Type::cmp); 138 return hb_sorted_array_t<Type> (*this); 139 } 140 void qsort (unsigned int start, unsigned int end) 141 { 142 end = MIN (end, len); 143 assert (start <= end); 144 ::qsort (arrayZ + start, end - start, item_size, Type::cmp); 145 } 146 147 /* 148 * Other methods. 149 */ 150 151 unsigned int get_size () const { return len * item_size; } 152 153 hb_array_t<Type> sub_array (unsigned int start_offset = 0, unsigned int *seg_count = nullptr /* IN/OUT */) const 154 { 155 if (!start_offset && !seg_count) 156 return *this; 157 158 unsigned int count = len; 159 if (unlikely (start_offset > count)) 160 count = 0; 161 else 162 count -= start_offset; 163 if (seg_count) 164 count = *seg_count = MIN (count, *seg_count); 165 return hb_array_t<Type> (arrayZ + start_offset, count); 166 } 167 hb_array_t<Type> sub_array (unsigned int start_offset, unsigned int seg_count) const 168 { return sub_array (start_offset, &seg_count); } 169 170 /* Only call if you allocated the underlying array using malloc() or similar. */ 171 void free () 172 { ::free ((void *) arrayZ); arrayZ = nullptr; len = 0; } 173 174 template <typename hb_sanitize_context_t> 175 bool sanitize (hb_sanitize_context_t *c) const 176 { return c->check_array (arrayZ, len); } 177 178 /* 179 * Members 180 */ 181 182 public: 183 Type *arrayZ; 184 unsigned int len; 185 }; 186 template <typename T> 187 inline hb_array_t<T> hb_array (T *array, unsigned int len) 188 { return hb_array_t<T> (array, len); } 189 190 191 enum hb_bfind_not_found_t 192 { 193 HB_BFIND_NOT_FOUND_DONT_STORE, 194 HB_BFIND_NOT_FOUND_STORE, 195 HB_BFIND_NOT_FOUND_STORE_CLOSEST, 196 }; 197 198 template <typename Type> 199 struct hb_sorted_array_t : hb_array_t<Type> 200 { 201 hb_sorted_array_t () : hb_array_t<Type> () {} 202 hb_sorted_array_t (const hb_array_t<Type> &o) : hb_array_t<Type> (o) {} 203 hb_sorted_array_t (Type *array_, unsigned int len_) : hb_array_t<Type> (array_, len_) {} 204 205 hb_sorted_array_t<Type> sub_array (unsigned int start_offset, unsigned int *seg_count /* IN/OUT */) const 206 { return hb_sorted_array_t<Type> (((const hb_array_t<Type> *) (this))->sub_array (start_offset, seg_count)); } 207 hb_sorted_array_t<Type> sub_array (unsigned int start_offset, unsigned int seg_count) const 208 { return sub_array (start_offset, &seg_count); } 209 210 template <typename T> 211 Type *bsearch (const T &x, Type *not_found = nullptr) 212 { 213 unsigned int i; 214 return bfind (x, &i) ? &this->arrayZ[i] : not_found; 215 } 216 template <typename T> 217 const Type *bsearch (const T &x, const Type *not_found = nullptr) const 218 { 219 unsigned int i; 220 return bfind (x, &i) ? &this->arrayZ[i] : not_found; 221 } 222 template <typename T> 223 bool bfind (const T &x, unsigned int *i = nullptr, 224 hb_bfind_not_found_t not_found = HB_BFIND_NOT_FOUND_DONT_STORE, 225 unsigned int to_store = (unsigned int) -1) const 226 { 227 int min = 0, max = (int) this->len - 1; 228 const Type *array = this->arrayZ; 229 while (min <= max) 230 { 231 int mid = ((unsigned int) min + (unsigned int) max) / 2; 232 int c = array[mid].cmp (x); 233 if (c < 0) 234 max = mid - 1; 235 else if (c > 0) 236 min = mid + 1; 237 else 238 { 239 if (i) 240 *i = mid; 241 return true; 242 } 243 } 244 if (i) 245 { 246 switch (not_found) 247 { 248 case HB_BFIND_NOT_FOUND_DONT_STORE: 249 break; 250 251 case HB_BFIND_NOT_FOUND_STORE: 252 *i = to_store; 253 break; 254 255 case HB_BFIND_NOT_FOUND_STORE_CLOSEST: 256 if (max < 0 || (max < (int) this->len && array[max].cmp (x) > 0)) 257 max++; 258 *i = max; 259 break; 260 } 261 } 262 return false; 263 } 264 }; 265 template <typename T> 266 inline hb_sorted_array_t<T> hb_sorted_array (T *array, unsigned int len) 267 { return hb_sorted_array_t<T> (array, len); } 268 269 270 typedef hb_array_t<const char> hb_bytes_t; 271 typedef hb_array_t<const unsigned char> hb_ubytes_t; 272 273 274 #endif /* HB_ARRAY_HH */ 275
