1 /*
2 * Copyright (C) 1999-2000 Harri Porten (porten@kde.org)
3 * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
4 * Copyright (C) 2009 Google Inc. All rights reserved.
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Library General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
10 *
11 * This library 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 * Library General Public License for more details.
15 *
16 * You should have received a copy of the GNU Library General Public License
17 * along with this library; see the file COPYING.LIB. If not, write to
18 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
19 * Boston, MA 02110-1301, USA.
20 *
21 */
22
23 #ifndef UString_h
24 #define UString_h
25
26 #include <wtf/text/StringImpl.h>
27
28 namespace JSC {
29
30 class UString {
31 public:
32 // Construct a null string, distinguishable from an empty string.
UString()33 UString() { }
34
35 // Construct a string with UTF-16 data.
36 UString(const UChar* characters, unsigned length);
37
38 // Construct a string with UTF-16 data, from a null-terminated source.
39 UString(const UChar*);
40
41 // Construct a string with latin1 data.
42 UString(const char* characters, unsigned length);
43
44 // Construct a string with latin1 data, from a null-terminated source.
45 UString(const char* characters);
46
47 // Construct a string referencing an existing StringImpl.
UString(StringImpl * impl)48 UString(StringImpl* impl) : m_impl(impl) { }
UString(PassRefPtr<StringImpl> impl)49 UString(PassRefPtr<StringImpl> impl) : m_impl(impl) { }
UString(RefPtr<StringImpl> impl)50 UString(RefPtr<StringImpl> impl) : m_impl(impl) { }
51
52 // Inline the destructor.
~UString()53 ALWAYS_INLINE ~UString() { }
54
swap(UString & o)55 void swap(UString& o) { m_impl.swap(o.m_impl); }
56
57 template<size_t inlineCapacity>
adopt(Vector<UChar,inlineCapacity> & vector)58 static UString adopt(Vector<UChar, inlineCapacity>& vector) { return StringImpl::adopt(vector); }
59
isNull()60 bool isNull() const { return !m_impl; }
isEmpty()61 bool isEmpty() const { return !m_impl || !m_impl->length(); }
62
impl()63 StringImpl* impl() const { return m_impl.get(); }
64
length()65 unsigned length() const
66 {
67 if (!m_impl)
68 return 0;
69 return m_impl->length();
70 }
71
characters()72 const UChar* characters() const
73 {
74 if (!m_impl)
75 return 0;
76 return m_impl->characters();
77 }
78
79 CString ascii() const;
80 CString latin1() const;
81 CString utf8(bool strict = false) const;
82
83 UChar operator[](unsigned index) const
84 {
85 if (!m_impl || index >= m_impl->length())
86 return 0;
87 return m_impl->characters()[index];
88 }
89
90 static UString number(int);
91 static UString number(unsigned);
92 static UString number(long);
93 static UString number(long long);
94 static UString number(double);
95
96 // Find a single character or string, also with match function & latin1 forms.
97 size_t find(UChar c, unsigned start = 0) const
98 { return m_impl ? m_impl->find(c, start) : notFound; }
99 size_t find(const UString& str, unsigned start = 0) const
100 { return m_impl ? m_impl->find(str.impl(), start) : notFound; }
101 size_t find(const char* str, unsigned start = 0) const
102 { return m_impl ? m_impl->find(str, start) : notFound; }
103
104 // Find the last instance of a single character or string.
105 size_t reverseFind(UChar c, unsigned start = UINT_MAX) const
106 { return m_impl ? m_impl->reverseFind(c, start) : notFound; }
107 size_t reverseFind(const UString& str, unsigned start = UINT_MAX) const
108 { return m_impl ? m_impl->reverseFind(str.impl(), start) : notFound; }
109
110 UString substringSharingImpl(unsigned pos, unsigned len = UINT_MAX) const;
111
112 private:
113 RefPtr<StringImpl> m_impl;
114 };
115
116 ALWAYS_INLINE bool operator==(const UString& s1, const UString& s2)
117 {
118 StringImpl* rep1 = s1.impl();
119 StringImpl* rep2 = s2.impl();
120 unsigned size1 = 0;
121 unsigned size2 = 0;
122
123 if (rep1 == rep2) // If they're the same rep, they're equal.
124 return true;
125
126 if (rep1)
127 size1 = rep1->length();
128
129 if (rep2)
130 size2 = rep2->length();
131
132 if (size1 != size2) // If the lengths are not the same, we're done.
133 return false;
134
135 if (!size1)
136 return true;
137
138 // At this point we know
139 // (a) that the strings are the same length and
140 // (b) that they are greater than zero length.
141 const UChar* d1 = rep1->characters();
142 const UChar* d2 = rep2->characters();
143
144 if (d1 == d2) // Check to see if the data pointers are the same.
145 return true;
146
147 // Do quick checks for sizes 1 and 2.
148 switch (size1) {
149 case 1:
150 return d1[0] == d2[0];
151 case 2:
152 return (d1[0] == d2[0]) & (d1[1] == d2[1]);
153 default:
154 return memcmp(d1, d2, size1 * sizeof(UChar)) == 0;
155 }
156 }
157
158
159 inline bool operator!=(const UString& s1, const UString& s2)
160 {
161 return !JSC::operator==(s1, s2);
162 }
163
164 bool operator<(const UString& s1, const UString& s2);
165 bool operator>(const UString& s1, const UString& s2);
166
167 bool operator==(const UString& s1, const char* s2);
168
169 inline bool operator!=(const UString& s1, const char* s2)
170 {
171 return !JSC::operator==(s1, s2);
172 }
173
174 inline bool operator==(const char *s1, const UString& s2)
175 {
176 return operator==(s2, s1);
177 }
178
179 inline bool operator!=(const char *s1, const UString& s2)
180 {
181 return !JSC::operator==(s1, s2);
182 }
183
codePointCompare(const UString & s1,const UString & s2)184 inline int codePointCompare(const UString& s1, const UString& s2)
185 {
186 return codePointCompare(s1.impl(), s2.impl());
187 }
188
189 struct UStringHash {
hashUStringHash190 static unsigned hash(StringImpl* key) { return key->hash(); }
equalUStringHash191 static bool equal(const StringImpl* a, const StringImpl* b)
192 {
193 if (a == b)
194 return true;
195 if (!a || !b)
196 return false;
197
198 unsigned aLength = a->length();
199 unsigned bLength = b->length();
200 if (aLength != bLength)
201 return false;
202
203 // FIXME: perhaps we should have a more abstract macro that indicates when
204 // going 4 bytes at a time is unsafe
205 #if CPU(ARM) || CPU(SH4) || CPU(MIPS)
206 const UChar* aChars = a->characters();
207 const UChar* bChars = b->characters();
208 for (unsigned i = 0; i != aLength; ++i) {
209 if (*aChars++ != *bChars++)
210 return false;
211 }
212 return true;
213 #else
214 /* Do it 4-bytes-at-a-time on architectures where it's safe */
215 const uint32_t* aChars = reinterpret_cast<const uint32_t*>(a->characters());
216 const uint32_t* bChars = reinterpret_cast<const uint32_t*>(b->characters());
217
218 unsigned halfLength = aLength >> 1;
219 for (unsigned i = 0; i != halfLength; ++i)
220 if (*aChars++ != *bChars++)
221 return false;
222
223 if (aLength & 1 && *reinterpret_cast<const uint16_t*>(aChars) != *reinterpret_cast<const uint16_t*>(bChars))
224 return false;
225
226 return true;
227 #endif
228 }
229
hashUStringHash230 static unsigned hash(const RefPtr<StringImpl>& key) { return key->hash(); }
equalUStringHash231 static bool equal(const RefPtr<StringImpl>& a, const RefPtr<StringImpl>& b)
232 {
233 return equal(a.get(), b.get());
234 }
235
hashUStringHash236 static unsigned hash(const UString& key) { return key.impl()->hash(); }
equalUStringHash237 static bool equal(const UString& a, const UString& b)
238 {
239 return equal(a.impl(), b.impl());
240 }
241
242 static const bool safeToCompareToEmptyOrDeleted = false;
243 };
244
245 } // namespace JSC
246
247 namespace WTF {
248
249 // UStringHash is the default hash for UString
250 template<typename T> struct DefaultHash;
251 template<> struct DefaultHash<JSC::UString> {
252 typedef JSC::UStringHash Hash;
253 };
254
255 template <> struct VectorTraits<JSC::UString> : SimpleClassVectorTraits { };
256
257 } // namespace WTF
258
259 #endif
260
261