security/sandbox/chromium/base/strings/string_piece.cc@6474c204b198
security/sandbox/chromium/base/strings/string_piece.cc
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 // Copied from strings/stringpiece.cc with modifications
6 #include "base/strings/string_piece.h"
8 #include <algorithm>
9 #include <ostream>
11 namespace base {
13 // MSVC doesn't like complex extern templates and DLLs.
14 #if !defined(COMPILER_MSVC)
15 namespace internal {
16 template class StringPieceDetail<std::string>;
17 template class StringPieceDetail<string16>;
18 } // namespace internal
20 template class BasicStringPiece<string16>;
21 #endif
23 bool operator==(const StringPiece& x, const StringPiece& y) {
24 if (x.size() != y.size())
25 return false;
27 return StringPiece::wordmemcmp(x.data(), y.data(), x.size()) == 0;
28 }
30 std::ostream& operator<<(std::ostream& o, const StringPiece& piece) {
31 o.write(piece.data(), static_cast<std::streamsize>(piece.size()));
32 return o;
33 }
35 namespace internal {
36 void CopyToString(const StringPiece& self, std::string* target) {
37 target->assign(!self.empty() ? self.data() : "", self.size());
38 }
40 void AppendToString(const StringPiece& self, std::string* target) {
41 if (!self.empty())
42 target->append(self.data(), self.size());
43 }
45 StringPiece::size_type copy(const StringPiece& self,
46 char* buf,
47 StringPiece::size_type n,
48 StringPiece::size_type pos) {
49 StringPiece::size_type ret = std::min(self.size() - pos, n);
50 memcpy(buf, self.data() + pos, ret);
51 return ret;
52 }
54 StringPiece::size_type find(const StringPiece& self,
55 const StringPiece& s,
56 StringPiece::size_type pos) {
57 if (pos > self.size())
58 return StringPiece::npos;
60 StringPiece::const_iterator result =
61 std::search(self.begin() + pos, self.end(), s.begin(), s.end());
62 const StringPiece::size_type xpos =
63 static_cast<size_t>(result - self.begin());
64 return xpos + s.size() <= self.size() ? xpos : StringPiece::npos;
65 }
67 StringPiece::size_type find(const StringPiece& self,
68 char c,
69 StringPiece::size_type pos) {
70 if (pos >= self.size())
71 return StringPiece::npos;
73 StringPiece::const_iterator result =
74 std::find(self.begin() + pos, self.end(), c);
75 return result != self.end() ?
76 static_cast<size_t>(result - self.begin()) : StringPiece::npos;
77 }
79 StringPiece::size_type rfind(const StringPiece& self,
80 const StringPiece& s,
81 StringPiece::size_type pos) {
82 if (self.size() < s.size())
83 return StringPiece::npos;
85 if (s.empty())
86 return std::min(self.size(), pos);
88 StringPiece::const_iterator last =
89 self.begin() + std::min(self.size() - s.size(), pos) + s.size();
90 StringPiece::const_iterator result =
91 std::find_end(self.begin(), last, s.begin(), s.end());
92 return result != last ?
93 static_cast<size_t>(result - self.begin()) : StringPiece::npos;
94 }
96 StringPiece::size_type rfind(const StringPiece& self,
97 char c,
98 StringPiece::size_type pos) {
99 if (self.size() == 0)
100 return StringPiece::npos;
102 for (StringPiece::size_type i = std::min(pos, self.size() - 1); ; --i) {
103 if (self.data()[i] == c)
104 return i;
105 if (i == 0)
106 break;
107 }
108 return StringPiece::npos;
109 }
111 // For each character in characters_wanted, sets the index corresponding
112 // to the ASCII code of that character to 1 in table. This is used by
113 // the find_.*_of methods below to tell whether or not a character is in
114 // the lookup table in constant time.
115 // The argument `table' must be an array that is large enough to hold all
116 // the possible values of an unsigned char. Thus it should be be declared
117 // as follows:
118 // bool table[UCHAR_MAX + 1]
119 static inline void BuildLookupTable(const StringPiece& characters_wanted,
120 bool* table) {
121 const StringPiece::size_type length = characters_wanted.length();
122 const char* const data = characters_wanted.data();
123 for (StringPiece::size_type i = 0; i < length; ++i) {
124 table[static_cast<unsigned char>(data[i])] = true;
125 }
126 }
128 StringPiece::size_type find_first_of(const StringPiece& self,
129 const StringPiece& s,
130 StringPiece::size_type pos) {
131 if (self.size() == 0 || s.size() == 0)
132 return StringPiece::npos;
134 // Avoid the cost of BuildLookupTable() for a single-character search.
135 if (s.size() == 1)
136 return find(self, s.data()[0], pos);
138 bool lookup[UCHAR_MAX + 1] = { false };
139 BuildLookupTable(s, lookup);
140 for (StringPiece::size_type i = pos; i < self.size(); ++i) {
141 if (lookup[static_cast<unsigned char>(self.data()[i])]) {
142 return i;
143 }
144 }
145 return StringPiece::npos;
146 }
148 StringPiece::size_type find_first_not_of(const StringPiece& self,
149 const StringPiece& s,
150 StringPiece::size_type pos) {
151 if (self.size() == 0)
152 return StringPiece::npos;
154 if (s.size() == 0)
155 return 0;
157 // Avoid the cost of BuildLookupTable() for a single-character search.
158 if (s.size() == 1)
159 return find_first_not_of(self, s.data()[0], pos);
161 bool lookup[UCHAR_MAX + 1] = { false };
162 BuildLookupTable(s, lookup);
163 for (StringPiece::size_type i = pos; i < self.size(); ++i) {
164 if (!lookup[static_cast<unsigned char>(self.data()[i])]) {
165 return i;
166 }
167 }
168 return StringPiece::npos;
169 }
171 StringPiece::size_type find_first_not_of(const StringPiece& self,
172 char c,
173 StringPiece::size_type pos) {
174 if (self.size() == 0)
175 return StringPiece::npos;
177 for (; pos < self.size(); ++pos) {
178 if (self.data()[pos] != c) {
179 return pos;
180 }
181 }
182 return StringPiece::npos;
183 }
185 StringPiece::size_type find_last_of(const StringPiece& self,
186 const StringPiece& s,
187 StringPiece::size_type pos) {
188 if (self.size() == 0 || s.size() == 0)
189 return StringPiece::npos;
191 // Avoid the cost of BuildLookupTable() for a single-character search.
192 if (s.size() == 1)
193 return rfind(self, s.data()[0], pos);
195 bool lookup[UCHAR_MAX + 1] = { false };
196 BuildLookupTable(s, lookup);
197 for (StringPiece::size_type i = std::min(pos, self.size() - 1); ; --i) {
198 if (lookup[static_cast<unsigned char>(self.data()[i])])
199 return i;
200 if (i == 0)
201 break;
202 }
203 return StringPiece::npos;
204 }
206 StringPiece::size_type find_last_not_of(const StringPiece& self,
207 const StringPiece& s,
208 StringPiece::size_type pos) {
209 if (self.size() == 0)
210 return StringPiece::npos;
212 StringPiece::size_type i = std::min(pos, self.size() - 1);
213 if (s.size() == 0)
214 return i;
216 // Avoid the cost of BuildLookupTable() for a single-character search.
217 if (s.size() == 1)
218 return find_last_not_of(self, s.data()[0], pos);
220 bool lookup[UCHAR_MAX + 1] = { false };
221 BuildLookupTable(s, lookup);
222 for (; ; --i) {
223 if (!lookup[static_cast<unsigned char>(self.data()[i])])
224 return i;
225 if (i == 0)
226 break;
227 }
228 return StringPiece::npos;
229 }
231 StringPiece::size_type find_last_not_of(const StringPiece& self,
232 char c,
233 StringPiece::size_type pos) {
234 if (self.size() == 0)
235 return StringPiece::npos;
237 for (StringPiece::size_type i = std::min(pos, self.size() - 1); ; --i) {
238 if (self.data()[i] != c)
239 return i;
240 if (i == 0)
241 break;
242 }
243 return StringPiece::npos;
244 }
246 StringPiece substr(const StringPiece& self,
247 StringPiece::size_type pos,
248 StringPiece::size_type n) {
249 if (pos > self.size()) pos = self.size();
250 if (n > self.size() - pos) n = self.size() - pos;
251 return StringPiece(self.data() + pos, n);
252 }
254 } // namespace internal
255 } // namespace base
