dburgess | 82c46ff | 2011-10-07 02:40:51 +0000 | [diff] [blame] | 1 | /**@file Simplified Vector template with aliases. */ |
| 2 | /* |
| 3 | * Copyright 2008 Free Software Foundation, Inc. |
| 4 | * |
| 5 | * This software is distributed under the terms of the GNU Affero Public License. |
| 6 | * See the COPYING file in the main directory for details. |
| 7 | * |
| 8 | * This use of this software may be subject to additional restrictions. |
| 9 | * See the LEGAL file in the main directory for details. |
| 10 | |
| 11 | This program is free software: you can redistribute it and/or modify |
| 12 | it under the terms of the GNU Affero General Public License as published by |
| 13 | the Free Software Foundation, either version 3 of the License, or |
| 14 | (at your option) any later version. |
| 15 | |
| 16 | This program is distributed in the hope that it will be useful, |
| 17 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 18 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 19 | GNU Affero General Public License for more details. |
| 20 | |
| 21 | You should have received a copy of the GNU Affero General Public License |
| 22 | along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 23 | |
| 24 | */ |
| 25 | |
| 26 | |
| 27 | |
| 28 | |
| 29 | #ifndef VECTOR_H |
| 30 | #define VECTOR_H |
| 31 | |
| 32 | #include <string.h> |
| 33 | #include <iostream> |
| 34 | #include <assert.h> |
| 35 | |
| 36 | |
| 37 | /** |
| 38 | A simplified Vector template with aliases. |
| 39 | Unlike std::vector, this class does not support dynamic resizing. |
| 40 | Unlike std::vector, this class does support "aliases" and subvectors. |
| 41 | */ |
| 42 | template <class T> class Vector { |
| 43 | |
| 44 | // TODO -- Replace memcpy calls with for-loops. |
| 45 | |
| 46 | public: |
| 47 | |
| 48 | /**@name Iterator types. */ |
| 49 | //@{ |
| 50 | typedef T* iterator; |
| 51 | typedef const T* const_iterator; |
| 52 | //@} |
| 53 | |
| 54 | protected: |
| 55 | |
| 56 | T* mData; ///< allocated data block, if any |
| 57 | T* mStart; ///< start of useful data |
| 58 | T* mEnd; ///< end of useful data + 1 |
| 59 | |
| 60 | public: |
| 61 | |
| 62 | /** Return the size of the Vector. */ |
| 63 | size_t size() const |
| 64 | { |
| 65 | assert(mStart>=mData); |
| 66 | assert(mEnd>=mStart); |
| 67 | return mEnd - mStart; |
| 68 | } |
| 69 | |
| 70 | /** Return size in bytes. */ |
| 71 | size_t bytes() const { return size()*sizeof(T); } |
| 72 | |
| 73 | /** Change the size of the Vector, discarding content. */ |
| 74 | void resize(size_t newSize) |
| 75 | { |
| 76 | if (mData!=NULL) delete[] mData; |
| 77 | if (newSize==0) mData=NULL; |
| 78 | else mData = new T[newSize]; |
| 79 | mStart = mData; |
| 80 | mEnd = mStart + newSize; |
| 81 | } |
| 82 | |
| 83 | /** Release memory and clear pointers. */ |
| 84 | void clear() { resize(0); } |
| 85 | |
| 86 | |
| 87 | /** Copy data from another vector. */ |
| 88 | void clone(const Vector<T>& other) |
| 89 | { |
| 90 | resize(other.size()); |
| 91 | memcpy(mData,other.mStart,other.bytes()); |
| 92 | } |
| 93 | |
| 94 | |
| 95 | |
| 96 | |
| 97 | //@{ |
| 98 | |
| 99 | /** Build an empty Vector of a given size. */ |
| 100 | Vector(size_t wSize=0):mData(NULL) { resize(wSize); } |
| 101 | |
| 102 | /** Build a Vector by shifting the data block. */ |
| 103 | Vector(Vector<T>& other) |
| 104 | :mData(other.mData),mStart(other.mStart),mEnd(other.mEnd) |
| 105 | { other.mData=NULL; } |
| 106 | |
| 107 | /** Build a Vector by copying another. */ |
| 108 | Vector(const Vector<T>& other):mData(NULL) { clone(other); } |
| 109 | |
| 110 | /** Build a Vector with explicit values. */ |
| 111 | Vector(T* wData, T* wStart, T* wEnd) |
| 112 | :mData(wData),mStart(wStart),mEnd(wEnd) |
| 113 | { } |
| 114 | |
| 115 | /** Build a vector from an existing block, NOT to be deleted upon destruction. */ |
| 116 | Vector(T* wStart, size_t span) |
| 117 | :mData(NULL),mStart(wStart),mEnd(wStart+span) |
| 118 | { } |
| 119 | |
| 120 | /** Build a Vector by concatenation. */ |
| 121 | Vector(const Vector<T>& other1, const Vector<T>& other2) |
| 122 | :mData(NULL) |
| 123 | { |
| 124 | resize(other1.size()+other2.size()); |
| 125 | memcpy(mStart, other1.mStart, other1.bytes()); |
| 126 | memcpy(mStart+other1.size(), other2.mStart, other2.bytes()); |
| 127 | } |
| 128 | |
| 129 | //@} |
| 130 | |
| 131 | /** Destroy a Vector, deleting held memory. */ |
| 132 | ~Vector() { clear(); } |
| 133 | |
| 134 | |
| 135 | |
| 136 | |
| 137 | //@{ |
| 138 | |
| 139 | /** Assign from another Vector, shifting ownership. */ |
| 140 | void operator=(Vector<T>& other) |
| 141 | { |
| 142 | clear(); |
| 143 | mData=other.mData; |
| 144 | mStart=other.mStart; |
| 145 | mEnd=other.mEnd; |
| 146 | other.mData=NULL; |
| 147 | } |
| 148 | |
| 149 | /** Assign from another Vector, copying. */ |
| 150 | void operator=(const Vector<T>& other) { clone(other); } |
| 151 | |
| 152 | //@} |
| 153 | |
| 154 | |
| 155 | //@{ |
| 156 | |
| 157 | /** Return an alias to a segment of this Vector. */ |
| 158 | Vector<T> segment(size_t start, size_t span) |
| 159 | { |
| 160 | T* wStart = mStart + start; |
| 161 | T* wEnd = wStart + span; |
| 162 | assert(wEnd<=mEnd); |
| 163 | return Vector<T>(NULL,wStart,wEnd); |
| 164 | } |
| 165 | |
| 166 | /** Return an alias to a segment of this Vector. */ |
| 167 | const Vector<T> segment(size_t start, size_t span) const |
| 168 | { |
| 169 | T* wStart = mStart + start; |
| 170 | T* wEnd = wStart + span; |
| 171 | assert(wEnd<=mEnd); |
| 172 | return Vector<T>(NULL,wStart,wEnd); |
| 173 | } |
| 174 | |
| 175 | Vector<T> head(size_t span) { return segment(0,span); } |
| 176 | const Vector<T> head(size_t span) const { return segment(0,span); } |
| 177 | Vector<T> tail(size_t start) { return segment(start,size()-start); } |
| 178 | const Vector<T> tail(size_t start) const { return segment(start,size()-start); } |
| 179 | |
| 180 | /** |
| 181 | Copy part of this Vector to a segment of another Vector. |
| 182 | @param other The other vector. |
| 183 | @param start The start point in the other vector. |
| 184 | @param span The number of elements to copy. |
| 185 | */ |
| 186 | void copyToSegment(Vector<T>& other, size_t start, size_t span) const |
| 187 | { |
| 188 | T* base = other.mStart + start; |
| 189 | assert(base+span<=other.mEnd); |
| 190 | assert(mStart+span<=mEnd); |
| 191 | memcpy(base,mStart,span*sizeof(T)); |
| 192 | } |
| 193 | |
| 194 | /** Copy all of this Vector to a segment of another Vector. */ |
| 195 | void copyToSegment(Vector<T>& other, size_t start=0) const { copyToSegment(other,start,size()); } |
| 196 | |
| 197 | void copyTo(Vector<T>& other) const { copyToSegment(other,0,size()); } |
| 198 | |
| 199 | /** |
| 200 | Copy a segment of this vector into another. |
| 201 | @param other The other vector (to copt into starting at 0.) |
| 202 | @param start The start point in this vector. |
| 203 | @param span The number of elements to copy. |
| 204 | */ |
| 205 | void segmentCopyTo(Vector<T>& other, size_t start, size_t span) const |
| 206 | { |
| 207 | const T* base = mStart + start; |
| 208 | assert(base+span<=mEnd); |
| 209 | assert(other.mStart+span<=other.mEnd); |
| 210 | memcpy(other.mStart,base,span*sizeof(T)); |
| 211 | } |
| 212 | |
| 213 | void fill(const T& val) |
| 214 | { |
| 215 | T* dp=mStart; |
| 216 | while (dp<mEnd) *dp++=val; |
| 217 | } |
| 218 | |
| 219 | void fill(const T& val, unsigned start, unsigned length) |
| 220 | { |
| 221 | T* dp=mStart+start; |
| 222 | T* end=dp+length; |
| 223 | assert(end<=mEnd); |
| 224 | while (dp<end) *dp++=val; |
| 225 | } |
| 226 | |
| 227 | |
| 228 | //@} |
| 229 | |
| 230 | |
| 231 | //@{ |
| 232 | |
| 233 | T& operator[](size_t index) |
| 234 | { |
| 235 | assert(mStart+index<mEnd); |
| 236 | return mStart[index]; |
| 237 | } |
| 238 | |
| 239 | const T& operator[](size_t index) const |
| 240 | { |
| 241 | assert(mStart+index<mEnd); |
| 242 | return mStart[index]; |
| 243 | } |
| 244 | |
| 245 | const T* begin() const { return mStart; } |
| 246 | T* begin() { return mStart; } |
| 247 | const T* end() const { return mEnd; } |
| 248 | T* end() { return mEnd; } |
| 249 | //@} |
| 250 | |
| 251 | |
| 252 | }; |
| 253 | |
| 254 | |
| 255 | |
| 256 | |
| 257 | /** Basic print operator for Vector objects. */ |
| 258 | template <class T> |
| 259 | std::ostream& operator<<(std::ostream& os, const Vector<T>& v) |
| 260 | { |
| 261 | for (unsigned i=0; i<v.size(); i++) os << v[i] << " "; |
| 262 | return os; |
| 263 | } |
| 264 | |
| 265 | |
| 266 | |
| 267 | #endif |
| 268 | // vim: ts=4 sw=4 |