《STL源码剖析》-- stl_vector.h

http://blog.csdn.net/mdl13412/article/details/6641998

《STL源码剖析》-- stl_vector.h

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// Filename: stl_vector.h



// Comment By: 凝霜

// E-mail: mdl2009@vip.qq.com

// Blog: http://blog.csdn.net/mdl13412



/*

*

* Copyright (c) 1994

* Hewlett-Packard Company

*

* Permission to use, copy, modify, distribute and sell this software

* and its documentation for any purpose is hereby granted without fee,

* provided that the above copyright notice appear in all copies and

* that both that copyright notice and this permission notice appear

* in supporting documentation. Hewlett-Packard Company makes no

* representations about the suitability of this software for any

* purpose. It is provided "as is" without express or implied warranty.

*

*

* Copyright (c) 1996

* Silicon Graphics Computer Systems, Inc.

*

* Permission to use, copy, modify, distribute and sell this software

* and its documentation for any purpose is hereby granted without fee,

* provided that the above copyright notice appear in all copies and

* that both that copyright notice and this permission notice appear

* in supporting documentation. Silicon Graphics makes no

* representations about the suitability of this software for any

* purpose. It is provided "as is" without express or implied warranty.

*/



/* NOTE: This is an internal header file, included by other STL headers.

* You should not attempt to use it directly.

*/



#ifndef __SGI_STL_INTERNAL_VECTOR_H

#define __SGI_STL_INTERNAL_VECTOR_H



__STL_BEGIN_NAMESPACE



#if defined(__sgi) && !defined(__GNUC__) && (_MIPS_SIM != _MIPS_SIM_ABI32)

#pragma set woff 1174

#endif





////////////////////////////////////////////////////////////////////////////////

//

////////////////////////////////////////////////////////////////////////////////





// 默认allocator为alloc, 其具体使用版本请参照<stl_alloc.h>

template <class T, class Alloc = alloc>

class vector

{

public:

// 标记为'STL标准强制要求'的typedefs用于提供iterator_traits<I>支持

typedef T value_type; // STL标准强制要求

typedef value_type* pointer; // STL标准强制要求

typedef const value_type* const_pointer;

// 由于vector的特性, 一般我们实作的时候都分配给其连续的内存空间,

// 所以其迭代器只需要定义成原生指针即可满足需要

typedef value_type* iterator; // STL标准强制要求

typedef const value_type* const_iterator;

typedef value_type& reference; // STL标准强制要求

typedef const value_type& const_reference;

typedef size_t size_type;

typedef ptrdiff_t difference_type; // STL标准强制要求



#ifdef __STL_CLASS_PARTIAL_SPECIALIZATION

typedef reverse_iterator<const_iterator> const_reverse_iterator;

typedef reverse_iterator<iterator> reverse_iterator;

#else /* __STL_CLASS_PARTIAL_SPECIALIZATION */

typedef reverse_iterator<const_iterator, value_type, const_reference,

difference_type> const_reverse_iterator;

typedef reverse_iterator<iterator, value_type, reference, difference_type>

reverse_iterator;

#endif /* __STL_CLASS_PARTIAL_SPECIALIZATION */



protected:

// 这个提供STL标准的allocator接口

typedef simple_alloc<value_type, Alloc> data_allocator;



iterator start; // 内存空间起始点

iterator finish; // 当前使用的内存空间结束点

iterator end_of_storage; // 实际分配内存空间的结束点



void insert_aux(iterator position, const T& x);



// 释放分配的内存空间

void deallocate()

{

// 由于使用的是data_allocator进行内存空间的分配,

// 所以需要同样嗲用data_allocator::deallocate()进行释放

// 如果直接释放, 对于data_allocator内部使用内存池的版本

// 就会发生错误

if (start) data_allocator::deallocate(start, end_of_storage - start);

}



void fill_initialize(size_type n, const T& value)

{

start = allocate_and_fill(n, value);

finish = start + n; // 设置当前使用内存空间的结束点

// 构造阶段, 此实作不多分配内存,

// 所以要设置内存空间结束点和, 已经使用的内存空间结束点相同

end_of_storage = finish;

}



public:

// 获取几种迭代器

iterator begin() { return start; }

const_iterator begin() const { return start; }

iterator end() { return finish; }

const_iterator end() const { return finish; }

reverse_iterator rbegin() { return reverse_iterator(end()); }

const_reverse_iterator rbegin() const {

return const_reverse_iterator(end());

}

reverse_iterator rend() { return reverse_iterator(begin()); }

const_reverse_iterator rend() const {

return const_reverse_iterator(begin());

}



// 返回当前对象个数

size_type size() const { return size_type(end() - begin()); }

size_type max_size() const { return size_type(-1) / sizeof(T); }

// 返回重新分配内存前最多能存储的对象个数

size_type capacity() const { return size_type(end_of_storage - begin()); }

bool empty() const { return begin() == end(); }

reference operator[](size_type n) { return *(begin() + n); }

const_reference operator[](size_type n) const { return *(begin() + n); }



// 本实作中默认构造出的vector不分配内存空间

vector() : start(0), finish(0), end_of_storage(0) {}



////////////////////////////////////////////////////////////////////////////////

// 本实作中给定个数和对象, 则只分配所需内存, 不会多分配

////////////////////////////////////////////////////////////////////////////////

// vector(size_type n, const T& value)

// ↓

// fill_initialize(n, value)

// ↓

// allocate_and_fill(n, value)

// ↓

// data_allocator::allocate(n) <stl_alloc.h>

// uninitialized_fill_n(result, n, x) <stl_uninitialized.h>

////////////////////////////////////////////////////////////////////////////////



vector(size_type n, const T& value) { fill_initialize(n, value); }

vector(int n, const T& value) { fill_initialize(n, value); }

vector(long n, const T& value) { fill_initialize(n, value); }



// 需要对象提供默认构造函数

explicit vector(size_type n) { fill_initialize(n, T()); }



////////////////////////////////////////////////////////////////////////////////

// 复制构造, 同样不会多分配内存

////////////////////////////////////////////////////////////////////////////////

// vector(const vector<T, Alloc>& x)

// ↓

// allocate_and_copy(x.end() - x.begin(), x.begin(), x.end());

// ↓

// data_allocator::allocate(n) <stl_alloc.h>

// uninitialized_copy(first, last, result); <stl_uninitialized.h>

////////////////////////////////////////////////////////////////////////////////



vector(const vector<T, Alloc>& x)

{

start = allocate_and_copy(x.end() - x.begin(), x.begin(), x.end());

finish = start + (x.end() - x.begin());

end_of_storage = finish;

}



// 复制指定区间的元素, 同样不多分配内存

#ifdef __STL_MEMBER_TEMPLATES

////////////////////////////////////////////////////////////////////////////////

// 复制一个区间进行构造, 可能会导致多分配内存

////////////////////////////////////////////////////////////////////////////////

// vector(InputIterator first, InputIterator last)

// ↓

// range_initialize(first, last, iterator_category(first));

// ↓

// for ( ; first != last; ++first)

// push_back(*first);

// 由于使用push_back()操作, 可能导致多次重复分配内存,个人感觉应该先

// data_allocator::allocate((last - first) * sizeof(T));

// 然后uninitialized_copy(first, last, result);

// 这样不会多分配内存， 也不会导致多次重新分配内存问题

////////////////////////////////////////////////////////////////////////////////



template <class InputIterator>

vector(InputIterator first, InputIterator last) :

start(0), finish(0), end_of_storage(0)

{

range_initialize(first, last, iterator_category(first));

}

#else /* __STL_MEMBER_TEMPLATES */



////////////////////////////////////////////////////////////////////////////////

// 复制一个区间进行构造, 可能会导致多分配内存

////////////////////////////////////////////////////////////////////////////////

// vector(const_iterator first, const_iterator last)

// ↓

// distance(first, last, n);

// ↓

// allocate_and_copy(n, first, last);

// ↓

// data_allocator::allocate(n) <stl_alloc.h>

// uninitialized_copy(first, last, result); <stl_uninitialized.h>

////////////////////////////////////////////////////////////////////////////////



vector(const_iterator first, const_iterator last) {

size_type n = 0;

distance(first, last, n);

start = allocate_and_copy(n, first, last);

finish = start + n;

end_of_storage = finish;

}

#endif /* __STL_MEMBER_TEMPLATES */



~vector()

{

// 析构对象

destroy(start, finish);

// 释放内存

deallocate();

}



vector<T, Alloc>& operator=(const vector<T, Alloc>& x);



////////////////////////////////////////////////////////////////////////////////

// 预留一定空间, 如果n < capacity(), 并不会减少空间

////////////////////////////////////////////////////////////////////////////////

// reserve(size_type n)

// ↓

// allocate_and_copy(n, start, finish)

// destroy(start, finish); <stl_construct.h>

// deallocate();

////////////////////////////////////////////////////////////////////////////////



void reserve(size_type n)

{

if (capacity() < n) {

const size_type old_size = size();

iterator tmp = allocate_and_copy(n, start, finish);

destroy(start, finish);

deallocate();

start = tmp;

finish = tmp + old_size;

end_of_storage = start + n;

}

}



// 提供访问函数

reference front() { return *begin(); }

const_reference front() const { return *begin(); }

reference back() { return *(end() - 1); }

const_reference back() const { return *(end() - 1); }



////////////////////////////////////////////////////////////////////////////////

// 向容器尾追加一个元素, 可能导致内存重新分配

////////////////////////////////////////////////////////////////////////////////

// push_back(const T& x)

// |

// |---------------- 容量已满?

// |

// ----------------------------

// No | | Yes

// | |

// ↓ ↓

// construct(finish, x); insert_aux(end(), x);

// ++finish; |

// |------ 内存不足, 重新分配

// | 大小为原来的2倍

// new_finish = data_allocator::allocate(len); <stl_alloc.h>

// uninitialized_copy(start, position, new_start); <stl_uninitialized.h>

// construct(new_finish, x); <stl_construct.h>

// ++new_finish;

// uninitialized_copy(position, finish, new_finish); <stl_uninitialized.h>

////////////////////////////////////////////////////////////////////////////////



void push_back(const T& x)

{

// 内存满足条件则直接追加元素, 否则需要重新分配内存空间

if (finish != end_of_storage) {

construct(finish, x);

++finish;

}

else

insert_aux(end(), x);

}



// 交换两个vector, 实际上是交换内部的状态指针

void swap(vector<T, Alloc>& x)

{

__STD::swap(start, x.start);

__STD::swap(finish, x.finish);

__STD::swap(end_of_storage, x.end_of_storage);

}



////////////////////////////////////////////////////////////////////////////////

// 在指定位置插入元素

////////////////////////////////////////////////////////////////////////////////

// insert(iterator position, const T& x)

// |

// |------------ 容量是否足够 && 是否是end()?

// |

// -------------------------------------------

// No | | Yes

// | |

// ↓ ↓

// insert_aux(position, x); construct(finish, x);

// | ++finish;

// |-------- 容量是否够用?

// |

// --------------------------------------------------

// Yes | | No

// | |

// ↓ |

// construct(finish, *(finish - 1)); |

// ++finish; |

// T x_copy = x; |

// copy_backward(position, finish - 2, finish - 1); |

// *position = x_copy; |

// ↓

// data_allocator::allocate(len); <stl_alloc.h>

// uninitialized_copy(start, position, new_start); <stl_uninitialized.h>

// construct(new_finish, x); <stl_construct.h>

// ++new_finish;

// uninitialized_copy(position, finish, new_finish); <stl_uninitialized.h>

// destroy(begin(), end()); <stl_construct.h>

// deallocate();

////////////////////////////////////////////////////////////////////////////////



iterator insert(iterator position, const T& x)

{

size_type n = position - begin();

if (finish != end_of_storage && position == end()) {

construct(finish, x);

++finish;

}

else

insert_aux(position, x);

return begin() + n;

}



iterator insert(iterator position) { return insert(position, T()); }



#ifdef __STL_MEMBER_TEMPLATES

////////////////////////////////////////////////////////////////////////////////

// 在指定位置插入一个区间

////////////////////////////////////////////////////////////////////////////////

// insert(iterator position, InputIterator first, InputIterator last)

// ↓

// range_insert(position, first, last, iterator_category(first));

// ↓

// for ( ; first != last; ++first) {

// pos = insert(pos, *first);

// ++pos;

// }

////////////////////////////////////////////////////////////////////////////////



template <class InputIterator>

void insert(iterator position, InputIterator first, InputIterator last)

{

range_insert(position, first, last, iterator_category(first));

}

#else /* __STL_MEMBER_TEMPLATES */

void insert(iterator position,

const_iterator first, const_iterator last);

#endif /* __STL_MEMBER_TEMPLATES */



void insert (iterator pos, size_type n, const T& x);



void insert (iterator pos, int n, const T& x)

{

insert(pos, (size_type) n, x);

}



void insert (iterator pos, long n, const T& x)

{

insert(pos, (size_type) n, x);

}



void pop_back()

{

--finish;

destroy(finish);

}



iterator erase(iterator position)

{

if (position + 1 != end())

copy(position + 1, finish, position);

--finish;

destroy(finish);

return position;

}



////////////////////////////////////////////////////////////////////////////////

// 擦除指定区间的元素

////////////////////////////////////////////////////////////////////////////////

// erase(iterator first, iterator last)

// ↓

// ---------- copy(last, finish, first); <stl_algobase.h>

// | destroy(i, finish); <stl_construct.h>

// |

// | -------------- copy(...)

// | 特化 | char *特化 memmove()

// ---------------------------------------|

// | 泛化 | wchar_t特化 copy(...)

// | -------------- memmove()

// |

// 调用__copy_dispatch<InputIterator,OutputIterator>()(first, last, result);

// 进行__copy(first, last, result, iterator_category(first));派发

// |

// |

// | random_access_iterator_tag

// --------------------------------------------------------------

// | input_iterator_tag |

// | |

// ↓ |

// __copy(..., input_iterator_tag) |

// for ( ; first != last; ++result, ++first) |

// *result = *first; ↓

// __copy(..., random_access_iterator_tag)

// __copy_d(first, last, result, distance_type(first));

// |

// |

// ↓

// for (Distance n = last - first; n > 0; --n, ++result, ++first)

// *result = *first;

////////////////////////////////////////////////////////////////////////////////

iterator erase(iterator first, iterator last)

{

iterator i = copy(last, finish, first);

// 析构掉需要析构的元素

destroy(i, finish);

finish = finish - (last - first);

return first;

}



// 调整size, 但是并不会重新分配内存空间

void resize(size_type new_size, const T& x)

{

if (new_size < size())

erase(begin() + new_size, end());

else

insert(end(), new_size - size(), x);

}

void resize(size_type new_size) { resize(new_size, T()); }



void clear() { erase(begin(), end()); }



protected:

// 分配空间, 并且复制对象到分配的空间处

iterator allocate_and_fill(size_type n, const T& x)

{

iterator result = data_allocator::allocate(n);

__STL_TRY {

uninitialized_fill_n(result, n, x);

return result;

}

__STL_UNWIND(data_allocator::deallocate(result, n));

}



// 分配空间并且拷贝一个区间的元素到新分配空间处

#ifdef __STL_MEMBER_TEMPLATES

template <class ForwardIterator>

iterator allocate_and_copy(size_type n,

ForwardIterator first, ForwardIterator last)

{

iterator result = data_allocator::allocate(n);

__STL_TRY {

uninitialized_copy(first, last, result);

return result;

}

__STL_UNWIND(data_allocator::deallocate(result, n));

}

#else /* __STL_MEMBER_TEMPLATES */

iterator allocate_and_copy(size_type n,

const_iterator first, const_iterator last)

{

iterator result = data_allocator::allocate(n);

__STL_TRY {

uninitialized_copy(first, last, result);

return result;

}

__STL_UNWIND(data_allocator::deallocate(result, n));

}

#endif /* __STL_MEMBER_TEMPLATES */





#ifdef __STL_MEMBER_TEMPLATES

// 初始化一个区间, 使用push_back()操作, 可能引发内存多次重新分配

// 解决方案见

// template <class InputIterator>

// vector(InputIterator first, InputIterator last)

// 我评注部分

template <class InputIterator>

void range_initialize(InputIterator first, InputIterator last,

input_iterator_tag)

{

for ( ; first != last; ++first)

push_back(*first);

}



// This function is only called by the constructor. We have to worry

// about resource leaks, but not about maintaining invariants.

template <class ForwardIterator>

void range_initialize(ForwardIterator first, ForwardIterator last,

forward_iterator_tag)

{

size_type n = 0;

distance(first, last, n);

start = allocate_and_copy(n, first, last);

finish = start + n;

end_of_storage = finish;

}



template <class InputIterator>

void range_insert(iterator pos,

InputIterator first, InputIterator last,

input_iterator_tag);



template <class ForwardIterator>

void range_insert(iterator pos,

ForwardIterator first, ForwardIterator last,

forward_iterator_tag);



#endif /* __STL_MEMBER_TEMPLATES */

};



////////////////////////////////////////////////////////////////////////////////

// vector实现部分

////////////////////////////////////////////////////////////////////////////////



template <class T, class Alloc>

inline bool operator==(const vector<T, Alloc>& x, const vector<T, Alloc>& y)

{

return x.size() == y.size() && equal(x.begin(), x.end(), y.begin());

}



// 字典序比较

template <class T, class Alloc>

inline bool operator<(const vector<T, Alloc>& x, const vector<T, Alloc>& y)

{

return lexicographical_compare(x.begin(), x.end(), y.begin(), y.end());

}



#ifdef __STL_FUNCTION_TMPL_PARTIAL_ORDER



template <class T, class Alloc>

inline void swap(vector<T, Alloc>& x, vector<T, Alloc>& y)

{

x.swap(y);

}



#endif /* __STL_FUNCTION_TMPL_PARTIAL_ORDER */



////////////////////////////////////////////////////////////////////////////////

// 重载赋值运算符

////////////////////////////////////////////////////////////////////////////////

// operator=(const vector<T, Alloc>& x)

// |

// |---------------- 是否是自赋值?

// ↓

// -----------------------------------------

// No | | Yes

// | |

// ↓ |------- 容量判断

// return *this; |

// ↓

// -----------------------------------------------------------------

// |x.size() > capacity() | size() >= x.size() | other

// | | |

// ↓ ↓ |

// 容量不足, 需要重新分配 容量足够, 只需要析构掉多余的对象 |

// allocate_and_copy( copy(x.begin(), x.end(), begin()); |

// x.end() - x.begin(), destroy(i, finish); |

// x.begin(), x.end()); |

// destroy(start, finish); |

// deallocate(); ↓

// copy(x.begin(), x.begin() + size(), start);

// uninitialized_copy(x.begin() + size(), x.end(), finish);

////////////////////////////////////////////////////////////////////////////////



template <class T, class Alloc>

vector<T, Alloc>& vector<T, Alloc>::operator=(const vector<T, Alloc>& x)

{

if (&x != this) {

// 如果x.size() > capacity()那么就需要重新分配内存

// 首先分配内存, 并将容器内原来的元素拷贝到新分配内存中

// 然后析构原容器中元素, 调整内存状态变量

if (x.size() > capacity()) {

iterator tmp = allocate_and_copy(x.end() - x.begin(),

x.begin(), x.end());

destroy(start, finish);

deallocate();

start = tmp;

end_of_storage = start + (x.end() - x.begin());

}

else if (size() >= x.size()) {

iterator i = copy(x.begin(), x.end(), begin());

destroy(i, finish);

}

else {

copy(x.begin(), x.begin() + size(), start);

uninitialized_copy(x.begin() + size(), x.end(), finish);

}

finish = start + x.size();

}

return *this;

}



////////////////////////////////////////////////////////////////////////////////

// 提供插入操作

////////////////////////////////////////////////////////////////////////////////

// insert_aux(iterator position, const T& x)

// |

// |---------------- 容量是否足够?

// ↓

// -----------------------------------------

// Yes | | No

// | |

// ↓ |

// 从opsition开始, 整体向后移动一个位置 |

// construct(finish, *(finish - 1)); |

// ++finish; |

// T x_copy = x; |

// copy_backward(position, finish - 2, finish - 1); |

// *position = x_copy; |

// ↓

// data_allocator::allocate(len);

// uninitialized_copy(start, position, new_start);

// construct(new_finish, x);

// ++new_finish;

// uninitialized_copy(position, finish, new_finish);

// destroy(begin(), end());

// deallocate();

////////////////////////////////////////////////////////////////////////////////



template <class T, class Alloc>

void vector<T, Alloc>::insert_aux(iterator position, const T& x)

{

if (finish != end_of_storage) { // 还有剩余内存

construct(finish, *(finish - 1));

++finish;

T x_copy = x;

copy_backward(position, finish - 2, finish - 1);

*position = x_copy;

}

else { // 内存不足, 需要重新分配

// 本实作中是按原内存2倍进行重新分配

const size_type old_size = size();

const size_type len = old_size != 0 ? 2 * old_size : 1;

iterator new_start = data_allocator::allocate(len);

iterator new_finish = new_start;

// 将内存重新配置

__STL_TRY {

new_finish = uninitialized_copy(start, position, new_start);

construct(new_finish, x);

++new_finish;

new_finish = uninitialized_copy(position, finish, new_finish);

}

// 分配失败则抛出异常

# ifdef __STL_USE_EXCEPTIONS

catch(...) {

destroy(new_start, new_finish);

data_allocator::deallocate(new_start, len);

throw;

}

# endif /* __STL_USE_EXCEPTIONS */

// 析构原容器中的对象

destroy(begin(), end());

// 释放原容器分配的内存

deallocate();

// 调整内存指针状态

start = new_start;

finish = new_finish;

end_of_storage = new_start + len;

}

}



////////////////////////////////////////////////////////////////////////////////

// 在指定位置插入n个元素

////////////////////////////////////////////////////////////////////////////////

// insert(iterator position, size_type n, const T& x)

// |

// |---------------- 插入元素个数是否为0?

// ↓

// -----------------------------------------

// No | | Yes

// | |

// | ↓

// | return;

// |----------- 内存是否足够?

// |

// -------------------------------------------------

// Yes | | No

// | |

// |------ (finish - position) > n? |

// | 分别调整指针 |

// ↓ |

// ---------------------------- |

// No | | Yes |

// | | |

// ↓ ↓ |

// 插入操作, 调整指针 插入操作, 调整指针 |

// ↓

// data_allocator::allocate(len);

// new_finish = uninitialized_copy(start, position, new_start);

// new_finish = uninitialized_fill_n(new_finish, n, x);

// new_finish = uninitialized_copy(position, finish, new_finish);

// destroy(start, finish);

// deallocate();

////////////////////////////////////////////////////////////////////////////////



template <class T, class Alloc>

void vector<T, Alloc>::insert(iterator position, size_type n, const T& x)

{

// 如果n为0则不进行任何操作

if (n != 0) {

if (size_type(end_of_storage - finish) >= n) { // 剩下的内存够分配

T x_copy = x;

const size_type elems_after = finish - position;

iterator old_finish = finish;

if (elems_after > n) {

uninitialized_copy(finish - n, finish, finish);

finish += n;

copy_backward(position, old_finish - n, old_finish);

fill(position, position + n, x_copy);

}

else {

uninitialized_fill_n(finish, n - elems_after, x_copy);

finish += n - elems_after;

uninitialized_copy(position, old_finish, finish);

finish += elems_after;

fill(position, old_finish, x_copy);

}

}

else { // 剩下的内存不够分配, 需要重新分配

const size_type old_size = size();

const size_type len = old_size + max(old_size, n);

iterator new_start = data_allocator::allocate(len);

iterator new_finish = new_start;

__STL_TRY {

new_finish = uninitialized_copy(start, position, new_start);

new_finish = uninitialized_fill_n(new_finish, n, x);

new_finish = uninitialized_copy(position, finish, new_finish);

}

# ifdef __STL_USE_EXCEPTIONS

catch(...) {

destroy(new_start, new_finish);

data_allocator::deallocate(new_start, len);

throw;

}

# endif /* __STL_USE_EXCEPTIONS */

destroy(start, finish);

deallocate();

start = new_start;

finish = new_finish;

end_of_storage = new_start + len;

}

}

}



#ifdef __STL_MEMBER_TEMPLATES



// 在指定位置插入指定区间的对象

template <class T, class Alloc> template <class InputIterator>

void vector<T, Alloc>::range_insert(iterator pos,

InputIterator first, InputIterator last,

input_iterator_tag)

{

for ( ; first != last; ++first) {

pos = insert(pos, *first);

++pos;

}

}



template <class T, class Alloc> template <class ForwardIterator>

void vector<T, Alloc>::range_insert(iterator position,

ForwardIterator first,

ForwardIterator last,

forward_iterator_tag)

{

if (first != last) {

size_type n = 0;

distance(first, last, n);

if (size_type(end_of_storage - finish) >= n) {

const size_type elems_after = finish - position;

iterator old_finish = finish;

if (elems_after > n) {

uninitialized_copy(finish - n, finish, finish);

finish += n;

copy_backward(position, old_finish - n, old_finish);

copy(first, last, position);

}

else {

ForwardIterator mid = first;

advance(mid, elems_after);

uninitialized_copy(mid, last, finish);

finish += n - elems_after;

uninitialized_copy(position, old_finish, finish);

finish += elems_after;

copy(first, mid, position);

}

}

else {

const size_type old_size = size();

const size_type len = old_size + max(old_size, n);

iterator new_start = data_allocator::allocate(len);

iterator new_finish = new_start;

__STL_TRY {

new_finish = uninitialized_copy(start, position, new_start);

new_finish = uninitialized_copy(first, last, new_finish);

new_finish = uninitialized_copy(position, finish, new_finish);

}

# ifdef __STL_USE_EXCEPTIONS

catch(...) {

destroy(new_start, new_finish);

data_allocator::deallocate(new_start, len);

throw;

}

# endif /* __STL_USE_EXCEPTIONS */

destroy(start, finish);

deallocate();

start = new_start;

finish = new_finish;

end_of_storage = new_start + len;

}

}

}



#else /* __STL_MEMBER_TEMPLATES */



template <class T, class Alloc>

void vector<T, Alloc>::insert(iterator position,

const_iterator first,

const_iterator last) {

if (first != last) {

size_type n = 0;

distance(first, last, n);

if (size_type(end_of_storage - finish) >= n) {

const size_type elems_after = finish - position;

iterator old_finish = finish;

if (elems_after > n) {

uninitialized_copy(finish - n, finish, finish);

finish += n;

copy_backward(position, old_finish - n, old_finish);

copy(first, last, position);

}

else {

uninitialized_copy(first + elems_after, last, finish);

finish += n - elems_after;

uninitialized_copy(position, old_finish, finish);

finish += elems_after;

copy(first, first + elems_after, position);

}

}

else {

const size_type old_size = size();

const size_type len = old_size + max(old_size, n);

iterator new_start = data_allocator::allocate(len);

iterator new_finish = new_start;

__STL_TRY {

new_finish = uninitialized_copy(start, position, new_start);

new_finish = uninitialized_copy(first, last, new_finish);

new_finish = uninitialized_copy(position, finish, new_finish);

}

# ifdef __STL_USE_EXCEPTIONS

catch(...) {

destroy(new_start, new_finish);

data_allocator::deallocate(new_start, len);

throw;

}

# endif /* __STL_USE_EXCEPTIONS */

destroy(start, finish);

deallocate();

start = new_start;

finish = new_finish;

end_of_storage = new_start + len;

}

}

}



#endif /* __STL_MEMBER_TEMPLATES */



#if defined(__sgi) && !defined(__GNUC__) && (_MIPS_SIM != _MIPS_SIM_ABI32)

#pragma reset woff 1174

#endif



__STL_END_NAMESPACE



#endif /* __SGI_STL_INTERNAL_VECTOR_H */



// Local Variables:

// mode:C++

// End: