1 /*  GRAPHITE2 LICENSING
2 
3     Copyright 2010, SIL International
4     All rights reserved.
5 
6     This library is free software; you can redistribute it and/or modify
7     it under the terms of the GNU Lesser General Public License as published
8     by the Free Software Foundation; either version 2.1 of License, or
9     (at your option) any later version.
10 
11     This program is distributed in the hope that it will be useful,
12     but WITHOUT ANY WARRANTY; without even the implied warranty of
13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14     Lesser General Public License for more details.
15 
16     You should also have received a copy of the GNU Lesser General Public
17     License along with this library in the file named "LICENSE".
18     If not, write to the Free Software Foundation, 51 Franklin Street,
19     Suite 500, Boston, MA 02110-1335, USA or visit their web page on the
20     internet at http://www.fsf.org/licenses/lgpl.html.
21 
22 Alternatively, the contents of this file may be used under the terms of the
23 Mozilla Public License (http://mozilla.org/MPL) or the GNU General Public
24 License, as published by the Free Software Foundation, either version 2
25 of the License or (at your option) any later version.
26 */
27 
28 // designed to have a limited subset of the std::vector api
29 #pragma once
30 
31 #include <cstddef>
32 #include <cassert>
33 #include <cstring>
34 #include <cstdlib>
35 #include <new>
36 
37 #include "Main.h"
38 
39 namespace graphite2 {
40 
41 template <typename T>
42 inline
distance(T * first,T * last)43 ptrdiff_t distance(T* first, T* last) { return last-first; }
44 
45 
46 template <typename T>
47 class Vector
48 {
49     T * m_first, *m_last, *m_end;
50 public:
51     typedef       T &   reference;
52     typedef const T &   const_reference;
53     typedef       T *   iterator;
54     typedef const T *   const_iterator;
55 
Vector()56     Vector() : m_first(0), m_last(0), m_end(0) {}
57     Vector(size_t n, const T& value = T())      : m_first(0), m_last(0), m_end(0) { insert(begin(), n, value); }
Vector(const Vector<T> & rhs)58     Vector(const Vector<T> &rhs)                : m_first(0), m_last(0), m_end(0) { insert(begin(), rhs.begin(), rhs.end()); }
59     template <typename I>
Vector(I first,const I last)60     Vector(I first, const I last)               : m_first(0), m_last(0), m_end(0) { insert(begin(), first, last); }
~Vector()61     ~Vector() { clear(); free(m_first); }
62 
begin()63     iterator            begin()         { return m_first; }
begin()64     const_iterator      begin() const   { return m_first; }
65 
end()66     iterator            end()           { return m_last; }
end()67     const_iterator      end() const     { return m_last; }
68 
empty()69     bool                empty() const   { return m_first == m_last; }
size()70     size_t              size() const    { return m_last - m_first; }
capacity()71     size_t              capacity() const{ return m_end - m_first; }
72 
73     void                reserve(size_t n);
74     void                resize(size_t n, const T & v = T());
75 
front()76     reference           front()         { assert(size() > 0); return *begin(); }
front()77     const_reference     front() const   { assert(size() > 0); return *begin(); }
back()78     reference           back()          { assert(size() > 0); return *(end()-1); }
back()79     const_reference     back() const    { assert(size() > 0); return *(end()-1); }
80 
81     Vector<T>         & operator = (const Vector<T> & rhs) { assign(rhs.begin(), rhs.end()); return *this; }
82     reference           operator [] (size_t n)          { assert(size() > n); return m_first[n]; }
83     const_reference     operator [] (size_t n) const    { assert(size() > n); return m_first[n]; }
84 
assign(size_t n,const T & u)85     void                assign(size_t n, const T& u)    { clear(); insert(begin(), n, u); }
assign(const_iterator first,const_iterator last)86     void                assign(const_iterator first, const_iterator last)      { clear(); insert(begin(), first, last); }
insert(iterator p,const T & x)87     iterator            insert(iterator p, const T & x) { p = _insert_default(p, 1); new (p) T(x); return p; }
88     void                insert(iterator p, size_t n, const T & x);
89     void                insert(iterator p, const_iterator first, const_iterator last);
pop_back()90     void                pop_back()              { assert(size() > 0); --m_last; }
push_back(const T & v)91     void                push_back(const T &v)   { if (m_last == m_end) reserve(size()+1); new (m_last++) T(v); }
92 
clear()93     void                clear()                 { erase(begin(), end()); }
erase(iterator p)94     iterator            erase(iterator p)       { return erase(p, p+1); }
95     iterator            erase(iterator first, iterator last);
96 
97 private:
98     iterator            _insert_default(iterator p, size_t n);
99 };
100 
101 template <typename T>
102 inline
reserve(size_t n)103 void Vector<T>::reserve(size_t n)
104 {
105     if (n > capacity())
106     {
107         const ptrdiff_t sz = size();
108         size_t requested;
109         if (checked_mul(n,sizeof(T), requested))  std::abort();
110         m_first = static_cast<T*>(realloc(m_first, requested));
111         if (!m_first)   std::abort();
112         m_last  = m_first + sz;
113         m_end   = m_first + n;
114     }
115 }
116 
117 template <typename T>
118 inline
resize(size_t n,const T & v)119 void Vector<T>::resize(size_t n, const T & v) {
120     const ptrdiff_t d = n-size();
121     if (d < 0)      erase(end()+d, end());
122     else if (d > 0) insert(end(), d, v);
123 }
124 
125 template<typename T>
126 inline
_insert_default(iterator p,size_t n)127 typename Vector<T>::iterator Vector<T>::_insert_default(iterator p, size_t n)
128 {
129     assert(begin() <= p && p <= end());
130     const ptrdiff_t i = p - begin();
131     reserve(((size() + n + 7) >> 3) << 3);
132     p = begin() + i;
133     // Move tail if there is one
134     if (p != end()) memmove(p + n, p, distance(p,end())*sizeof(T));
135     m_last += n;
136     return p;
137 }
138 
139 template<typename T>
140 inline
insert(iterator p,size_t n,const T & x)141 void Vector<T>::insert(iterator p, size_t n, const T & x)
142 {
143     p = _insert_default(p, n);
144     // Copy in elements
145     for (; n; --n, ++p) { new (p) T(x); }
146 }
147 
148 template<typename T>
149 inline
insert(iterator p,const_iterator first,const_iterator last)150 void Vector<T>::insert(iterator p, const_iterator first, const_iterator last)
151 {
152     p = _insert_default(p, distance(first, last));
153     // Copy in elements
154     for (;first != last; ++first, ++p) { new (p) T(*first); }
155 }
156 
157 template<typename T>
158 inline
erase(iterator first,iterator last)159 typename Vector<T>::iterator Vector<T>::erase(iterator first, iterator last)
160 {
161     for (iterator e = first; e != last; ++e) e->~T();
162     const size_t sz = distance(first, last);
163     if (m_last != last) memmove(first, last, distance(last,end())*sizeof(T));
164     m_last -= sz;
165     return first;
166 }
167 
168 } // namespace graphite2
169