1 | // Boost string_algo library replace_storage.hpp header file ---------------------------// |
2 | |
3 | // Copyright Pavol Droba 2002-2003. |
4 | // |
5 | // Distributed under the Boost Software License, Version 1.0. |
6 | // (See accompanying file LICENSE_1_0.txt or copy at |
7 | // http://www.boost.org/LICENSE_1_0.txt) |
8 | |
9 | // See http://www.boost.org/ for updates, documentation, and revision history. |
10 | |
11 | #ifndef BOOST_STRING_REPLACE_STORAGE_DETAIL_HPP |
12 | #define BOOST_STRING_REPLACE_STORAGE_DETAIL_HPP |
13 | |
14 | #include <boost/algorithm/string/config.hpp> |
15 | #include <algorithm> |
16 | #include <boost/mpl/bool.hpp> |
17 | #include <boost/algorithm/string/sequence_traits.hpp> |
18 | #include <boost/algorithm/string/detail/sequence.hpp> |
19 | |
20 | namespace boost { |
21 | namespace algorithm { |
22 | namespace detail { |
23 | |
24 | // storage handling routines -----------------------------------------------// |
25 | |
26 | template< typename StorageT, typename OutputIteratorT > |
27 | inline OutputIteratorT move_from_storage( |
28 | StorageT& Storage, |
29 | OutputIteratorT DestBegin, |
30 | OutputIteratorT DestEnd ) |
31 | { |
32 | OutputIteratorT OutputIt=DestBegin; |
33 | |
34 | while( !Storage.empty() && OutputIt!=DestEnd ) |
35 | { |
36 | *OutputIt=Storage.front(); |
37 | Storage.pop_front(); |
38 | ++OutputIt; |
39 | } |
40 | |
41 | return OutputIt; |
42 | } |
43 | |
44 | template< typename StorageT, typename WhatT > |
45 | inline void copy_to_storage( |
46 | StorageT& Storage, |
47 | const WhatT& What ) |
48 | { |
49 | Storage.insert( Storage.end(), ::boost::begin(What), ::boost::end(What) ); |
50 | } |
51 | |
52 | |
53 | // process segment routine -----------------------------------------------// |
54 | |
55 | template< bool HasStableIterators > |
56 | struct process_segment_helper |
57 | { |
58 | // Optimized version of process_segment for generic sequence |
59 | template< |
60 | typename StorageT, |
61 | typename InputT, |
62 | typename ForwardIteratorT > |
63 | ForwardIteratorT operator()( |
64 | StorageT& Storage, |
65 | InputT& /*Input*/, |
66 | ForwardIteratorT InsertIt, |
67 | ForwardIteratorT SegmentBegin, |
68 | ForwardIteratorT SegmentEnd ) |
69 | { |
70 | // Copy data from the storage until the beginning of the segment |
71 | ForwardIteratorT It=::boost::algorithm::detail::move_from_storage( Storage, InsertIt, SegmentBegin ); |
72 | |
73 | // 3 cases are possible : |
74 | // a) Storage is empty, It==SegmentBegin |
75 | // b) Storage is empty, It!=SegmentBegin |
76 | // c) Storage is not empty |
77 | |
78 | if( Storage.empty() ) |
79 | { |
80 | if( It==SegmentBegin ) |
81 | { |
82 | // Case a) everything is grand, just return end of segment |
83 | return SegmentEnd; |
84 | } |
85 | else |
86 | { |
87 | // Case b) move the segment backwards |
88 | return std::copy( SegmentBegin, SegmentEnd, It ); |
89 | } |
90 | } |
91 | else |
92 | { |
93 | // Case c) -> shift the segment to the left and keep the overlap in the storage |
94 | while( It!=SegmentEnd ) |
95 | { |
96 | // Store value into storage |
97 | Storage.push_back( *It ); |
98 | // Get the top from the storage and put it here |
99 | *It=Storage.front(); |
100 | Storage.pop_front(); |
101 | |
102 | // Advance |
103 | ++It; |
104 | } |
105 | |
106 | return It; |
107 | } |
108 | } |
109 | }; |
110 | |
111 | template<> |
112 | struct process_segment_helper< true > |
113 | { |
114 | // Optimized version of process_segment for list-like sequence |
115 | template< |
116 | typename StorageT, |
117 | typename InputT, |
118 | typename ForwardIteratorT > |
119 | ForwardIteratorT operator()( |
120 | StorageT& Storage, |
121 | InputT& Input, |
122 | ForwardIteratorT InsertIt, |
123 | ForwardIteratorT SegmentBegin, |
124 | ForwardIteratorT SegmentEnd ) |
125 | |
126 | { |
127 | // Call replace to do the job |
128 | ::boost::algorithm::detail::replace( Input, InsertIt, SegmentBegin, Storage ); |
129 | // Empty the storage |
130 | Storage.clear(); |
131 | // Iterators were not changed, simply return the end of segment |
132 | return SegmentEnd; |
133 | } |
134 | }; |
135 | |
136 | // Process one segment in the replace_all algorithm |
137 | template< |
138 | typename StorageT, |
139 | typename InputT, |
140 | typename ForwardIteratorT > |
141 | inline ForwardIteratorT process_segment( |
142 | StorageT& Storage, |
143 | InputT& Input, |
144 | ForwardIteratorT InsertIt, |
145 | ForwardIteratorT SegmentBegin, |
146 | ForwardIteratorT SegmentEnd ) |
147 | { |
148 | return |
149 | process_segment_helper< |
150 | has_stable_iterators<InputT>::value>()( |
151 | Storage, Input, InsertIt, SegmentBegin, SegmentEnd ); |
152 | } |
153 | |
154 | |
155 | } // namespace detail |
156 | } // namespace algorithm |
157 | } // namespace boost |
158 | |
159 | #endif // BOOST_STRING_REPLACE_STORAGE_DETAIL_HPP |
160 | |