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bx/include/tinystl/string.h
2025-01-25 14:09:15 -08:00

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/*-
* Copyright 2012-2018 Matthew Endsley
* All rights reserved
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted providing that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef TINYSTL_STRING_H
#define TINYSTL_STRING_H
#include <tinystl/allocator.h>
#include <tinystl/stddef.h>
#include <tinystl/hash.h>
namespace tinystl {
template<typename Allocator>
class basic_string {
public:
basic_string();
basic_string(const basic_string& other);
basic_string(basic_string&& other);
basic_string(const char* sz);
basic_string(const char* sz, size_t len);
~basic_string();
basic_string& operator=(const basic_string& other);
basic_string& operator=(basic_string&& other);
const char* c_str() const;
size_t size() const;
void reserve(size_t size);
void resize(size_t size);
void clear();
void append(const char* first, const char* last);
void assign(const char* s, size_t n);
void shrink_to_fit();
void swap(basic_string& other);
private:
typedef char* pointer;
pointer m_first;
pointer m_last;
pointer m_capacity;
static const size_t c_nbuffer = 12;
char m_buffer[12];
};
template<typename allocator>
inline basic_string<allocator>::basic_string()
: m_first(m_buffer)
, m_last(m_buffer)
, m_capacity(m_buffer + c_nbuffer)
{
resize(0);
}
template<typename allocator>
inline basic_string<allocator>::basic_string(const basic_string& other)
: m_first(m_buffer)
, m_last(m_buffer)
, m_capacity(m_buffer + c_nbuffer)
{
reserve(other.size());
append(other.m_first, other.m_last);
}
template<typename allocator>
inline basic_string<allocator>::basic_string(basic_string&& other)
{
if (other.m_first == other.m_buffer) {
m_first = m_buffer;
m_last = m_buffer;
m_capacity = m_buffer + c_nbuffer;
reserve(other.size());
append(other.m_first, other.m_last);
} else {
m_first = other.m_first;
m_last = other.m_last;
m_capacity = other.m_capacity;
}
other.m_first = other.m_last = other.m_buffer;
other.m_capacity = other.m_buffer + c_nbuffer;
other.resize(0);
}
template<typename allocator>
inline basic_string<allocator>::basic_string(const char* sz)
: m_first(m_buffer)
, m_last(m_buffer)
, m_capacity(m_buffer + c_nbuffer)
{
size_t len = 0;
for (const char* it = sz; *it; ++it)
++len;
reserve(len);
append(sz, sz + len);
}
template<typename allocator>
inline basic_string<allocator>::basic_string(const char* sz, size_t len)
: m_first(m_buffer)
, m_last(m_buffer)
, m_capacity(m_buffer + c_nbuffer)
{
reserve(len);
append(sz, sz + len);
}
template<typename allocator>
inline basic_string<allocator>::~basic_string() {
if (m_first != m_buffer)
allocator::static_deallocate(m_first, m_capacity - m_first);
}
template<typename allocator>
inline basic_string<allocator>& basic_string<allocator>::operator=(const basic_string& other) {
basic_string(other).swap(*this);
return *this;
}
template<typename allocator>
inline basic_string<allocator>& basic_string<allocator>::operator=(basic_string&& other) {
basic_string(static_cast<basic_string&&>(other)).swap(*this);
return *this;
}
template<typename allocator>
inline const char* basic_string<allocator>::c_str() const {
return m_first;
}
template<typename allocator>
inline size_t basic_string<allocator>::size() const
{
return (size_t)(m_last - m_first);
}
template<typename allocator>
inline void basic_string<allocator>::reserve(size_t capacity) {
if (m_first + capacity + 1 <= m_capacity)
return;
const size_t size = (size_t)(m_last - m_first);
pointer newfirst = (pointer)allocator::static_allocate(capacity + 1);
for (pointer it = m_first, newit = newfirst, end = m_last; it != end; ++it, ++newit)
*newit = *it;
if (m_first != m_buffer)
allocator::static_deallocate(m_first, m_capacity - m_first);
m_first = newfirst;
m_last = newfirst + size;
m_capacity = m_first + capacity;
}
template<typename allocator>
inline void basic_string<allocator>::resize(size_t size) {
const size_t prevSize = m_last-m_first;
reserve(size);
if (size > prevSize)
for (pointer it = m_last, end = m_first + size + 1; it < end; ++it)
*it = 0;
else if (m_last != m_first)
m_first[size] = 0;
m_last = m_first + size;
}
template<typename allocator>
inline void basic_string<allocator>::clear() {
resize(0);
}
template<typename allocator>
inline void basic_string<allocator>::append(const char* first, const char* last) {
const size_t newsize = (size_t)((m_last - m_first) + (last - first) + 1);
if (m_first + newsize > m_capacity)
reserve((newsize * 3) / 2);
for (; first != last; ++m_last, ++first)
*m_last = *first;
*m_last = 0;
}
template<typename allocator>
inline void basic_string<allocator>::assign(const char* sz, size_t n) {
clear();
append(sz, sz+n);
}
template<typename allocator>
inline void basic_string<allocator>::shrink_to_fit() {
if (m_first == m_buffer) {
} else if (m_last == m_first) {
const size_t capacity = (size_t)(m_capacity - m_first);
if (capacity)
allocator::static_deallocate(m_first, capacity+1);
m_capacity = m_first;
} else if (m_capacity != m_last) {
const size_t size = (size_t)(m_last - m_first);
char* newfirst = (pointer)allocator::static_allocate(size+1);
for (pointer in = m_first, out = newfirst; in != m_last + 1; ++in, ++out)
*out = *in;
if (m_first != m_capacity)
allocator::static_deallocate(m_first, m_capacity+1-m_first);
m_first = newfirst;
m_last = newfirst+size;
m_capacity = m_last;
}
}
template<typename allocator>
inline void basic_string<allocator>::swap(basic_string& other) {
const pointer tfirst = m_first, tlast = m_last, tcapacity = m_capacity;
m_first = other.m_first, m_last = other.m_last, m_capacity = other.m_capacity;
other.m_first = tfirst, other.m_last = tlast, other.m_capacity = tcapacity;
char tbuffer[c_nbuffer];
if (m_first == other.m_buffer)
for (pointer it = other.m_buffer, end = m_last, out = tbuffer; it != end; ++it, ++out)
*out = *it;
if (other.m_first == m_buffer) {
other.m_last = other.m_last - other.m_first + other.m_buffer;
other.m_first = other.m_buffer;
other.m_capacity = other.m_buffer + c_nbuffer;
for (pointer it = other.m_first, end = other.m_last, in = m_buffer; it != end; ++it, ++in)
*it = *in;
*other.m_last = 0;
}
if (m_first == other.m_buffer) {
m_last = m_last - m_first + m_buffer;
m_first = m_buffer;
m_capacity = m_buffer + c_nbuffer;
for (pointer it = m_first, end = m_last, in = tbuffer; it != end; ++it, ++in)
*it = *in;
*m_last = 0;
}
}
template<typename allocatorl, typename allocatorr>
inline bool operator==(const basic_string<allocatorl>& lhs, const basic_string<allocatorr>& rhs) {
typedef const char* pointer;
const size_t lsize = lhs.size(), rsize = rhs.size();
if (lsize != rsize)
return false;
pointer lit = lhs.c_str(), rit = rhs.c_str();
pointer lend = lit + lsize;
while (lit != lend)
if (*lit++ != *rit++)
return false;
return true;
}
template<typename allocator>
static inline size_t hash(const basic_string<allocator>& value) {
return hash_string(value.c_str(), value.size());
}
typedef basic_string<TINYSTL_ALLOCATOR> string;
}
#endif