String8.h revision 4485d0d966d062d1b45b635e2447a2d2f96c3f38 
1/*
2 * Copyright (C) 2005 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef ANDROID_STRING8_H
18#define ANDROID_STRING8_H
19
20#include <utils/Errors.h>
21#include <utils/SharedBuffer.h>
22#include <utils/Unicode.h>
23#include <utils/TypeHelpers.h>
24
25#include <string.h> // for strcmp
26#include <stdarg.h>
27
28// ---------------------------------------------------------------------------
29
30namespace android {
31
32class String16;
33class TextOutput;
34
35//! This is a string holding UTF-8 characters. Does not allow the value more
36// than 0x10FFFF, which is not valid unicode codepoint.
37class String8
38{
39public:
40    /* use String8(StaticLinkage) if you're statically linking against
41     * libutils and declaring an empty static String8, e.g.:
42     *
43     *   static String8 sAStaticEmptyString(String8::kEmptyString);
44     *   static String8 sAnotherStaticEmptyString(sAStaticEmptyString);
45     */
46    enum StaticLinkage { kEmptyString };
47
48                                String8();
49    explicit                    String8(StaticLinkage);
50                                String8(const String8& o);
51    explicit                    String8(const char* o);
52    explicit                    String8(const char* o, size_t numChars);
53
54    explicit                    String8(const String16& o);
55    explicit                    String8(const char16_t* o);
56    explicit                    String8(const char16_t* o, size_t numChars);
57    explicit                    String8(const char32_t* o);
58    explicit                    String8(const char32_t* o, size_t numChars);
59                                ~String8();
60
61    static inline const String8 empty();
62
63    static String8              format(const char* fmt, ...) __attribute__((format (printf, 1, 2)));
64    static String8              formatV(const char* fmt, va_list args);
65
66    inline  const char*         string() const;
67    inline  size_t              size() const;
68    inline  size_t              length() const;
69    inline  size_t              bytes() const;
70    inline  bool                isEmpty() const;
71
72    inline  const SharedBuffer* sharedBuffer() const;
73
74            void                clear();
75
76            void                setTo(const String8& other);
77            status_t            setTo(const char* other);
78            status_t            setTo(const char* other, size_t numChars);
79            status_t            setTo(const char16_t* other, size_t numChars);
80            status_t            setTo(const char32_t* other,
81                                      size_t length);
82
83            status_t            append(const String8& other);
84            status_t            append(const char* other);
85            status_t            append(const char* other, size_t numChars);
86
87            status_t            appendFormat(const char* fmt, ...)
88                    __attribute__((format (printf, 2, 3)));
89            status_t            appendFormatV(const char* fmt, va_list args);
90
91            // Note that this function takes O(N) time to calculate the value.
92            // No cache value is stored.
93            size_t              getUtf32Length() const;
94            int32_t             getUtf32At(size_t index,
95                                           size_t *next_index) const;
96            void                getUtf32(char32_t* dst) const;
97
98    inline  String8&            operator=(const String8& other);
99    inline  String8&            operator=(const char* other);
100
101    inline  String8&            operator+=(const String8& other);
102    inline  String8             operator+(const String8& other) const;
103
104    inline  String8&            operator+=(const char* other);
105    inline  String8             operator+(const char* other) const;
106
107    inline  int                 compare(const String8& other) const;
108
109    inline  bool                operator<(const String8& other) const;
110    inline  bool                operator<=(const String8& other) const;
111    inline  bool                operator==(const String8& other) const;
112    inline  bool                operator!=(const String8& other) const;
113    inline  bool                operator>=(const String8& other) const;
114    inline  bool                operator>(const String8& other) const;
115
116    inline  bool                operator<(const char* other) const;
117    inline  bool                operator<=(const char* other) const;
118    inline  bool                operator==(const char* other) const;
119    inline  bool                operator!=(const char* other) const;
120    inline  bool                operator>=(const char* other) const;
121    inline  bool                operator>(const char* other) const;
122
123    inline                      operator const char*() const;
124
125            char*               lockBuffer(size_t size);
126            void                unlockBuffer();
127            status_t            unlockBuffer(size_t size);
128
129            // return the index of the first byte of other in this at or after
130            // start, or -1 if not found
131            ssize_t             find(const char* other, size_t start = 0) const;
132
133            void                toLower();
134            void                toLower(size_t start, size_t numChars);
135            void                toUpper();
136            void                toUpper(size_t start, size_t numChars);
137
138    /*
139     * These methods operate on the string as if it were a path name.
140     */
141
142    /*
143     * Set the filename field to a specific value.
144     *
145     * Normalizes the filename, removing a trailing '/' if present.
146     */
147    void setPathName(const char* name);
148    void setPathName(const char* name, size_t numChars);
149
150    /*
151     * Get just the filename component.
152     *
153     * "/tmp/foo/bar.c" --> "bar.c"
154     */
155    String8 getPathLeaf(void) const;
156
157    /*
158     * Remove the last (file name) component, leaving just the directory
159     * name.
160     *
161     * "/tmp/foo/bar.c" --> "/tmp/foo"
162     * "/tmp" --> "" // ????? shouldn't this be "/" ???? XXX
163     * "bar.c" --> ""
164     */
165    String8 getPathDir(void) const;
166
167    /*
168     * Retrieve the front (root dir) component.  Optionally also return the
169     * remaining components.
170     *
171     * "/tmp/foo/bar.c" --> "tmp" (remain = "foo/bar.c")
172     * "/tmp" --> "tmp" (remain = "")
173     * "bar.c" --> "bar.c" (remain = "")
174     */
175    String8 walkPath(String8* outRemains = NULL) const;
176
177    /*
178     * Return the filename extension.  This is the last '.' and any number
179     * of characters that follow it.  The '.' is included in case we
180     * decide to expand our definition of what constitutes an extension.
181     *
182     * "/tmp/foo/bar.c" --> ".c"
183     * "/tmp" --> ""
184     * "/tmp/foo.bar/baz" --> ""
185     * "foo.jpeg" --> ".jpeg"
186     * "foo." --> ""
187     */
188    String8 getPathExtension(void) const;
189
190    /*
191     * Return the path without the extension.  Rules for what constitutes
192     * an extension are described in the comment for getPathExtension().
193     *
194     * "/tmp/foo/bar.c" --> "/tmp/foo/bar"
195     */
196    String8 getBasePath(void) const;
197
198    /*
199     * Add a component to the pathname.  We guarantee that there is
200     * exactly one path separator between the old path and the new.
201     * If there is no existing name, we just copy the new name in.
202     *
203     * If leaf is a fully qualified path (i.e. starts with '/', it
204     * replaces whatever was there before.
205     */
206    String8& appendPath(const char* leaf);
207    String8& appendPath(const String8& leaf)  { return appendPath(leaf.string()); }
208
209    /*
210     * Like appendPath(), but does not affect this string.  Returns a new one instead.
211     */
212    String8 appendPathCopy(const char* leaf) const
213                                             { String8 p(*this); p.appendPath(leaf); return p; }
214    String8 appendPathCopy(const String8& leaf) const { return appendPathCopy(leaf.string()); }
215
216    /*
217     * Converts all separators in this string to /, the default path separator.
218     *
219     * If the default OS separator is backslash, this converts all
220     * backslashes to slashes, in-place. Otherwise it does nothing.
221     * Returns self.
222     */
223    String8& convertToResPath();
224
225private:
226            status_t            real_append(const char* other, size_t numChars);
227            char*               find_extension(void) const;
228
229            const char* mString;
230};
231
232// String8 can be trivially moved using memcpy() because moving does not
233// require any change to the underlying SharedBuffer contents or reference count.
234ANDROID_TRIVIAL_MOVE_TRAIT(String8)
235
236// ---------------------------------------------------------------------------
237// No user servicable parts below.
238
239inline int compare_type(const String8& lhs, const String8& rhs)
240{
241    return lhs.compare(rhs);
242}
243
244inline int strictly_order_type(const String8& lhs, const String8& rhs)
245{
246    return compare_type(lhs, rhs) < 0;
247}
248
249inline const String8 String8::empty() {
250    return String8();
251}
252
253inline const char* String8::string() const
254{
255    return mString;
256}
257
258inline size_t String8::length() const
259{
260    return SharedBuffer::sizeFromData(mString)-1;
261}
262
263inline size_t String8::size() const
264{
265    return length();
266}
267
268inline bool String8::isEmpty() const
269{
270    return length() == 0;
271}
272
273inline size_t String8::bytes() const
274{
275    return SharedBuffer::sizeFromData(mString)-1;
276}
277
278inline const SharedBuffer* String8::sharedBuffer() const
279{
280    return SharedBuffer::bufferFromData(mString);
281}
282
283inline String8& String8::operator=(const String8& other)
284{
285    setTo(other);
286    return *this;
287}
288
289inline String8& String8::operator=(const char* other)
290{
291    setTo(other);
292    return *this;
293}
294
295inline String8& String8::operator+=(const String8& other)
296{
297    append(other);
298    return *this;
299}
300
301inline String8 String8::operator+(const String8& other) const
302{
303    String8 tmp(*this);
304    tmp += other;
305    return tmp;
306}
307
308inline String8& String8::operator+=(const char* other)
309{
310    append(other);
311    return *this;
312}
313
314inline String8 String8::operator+(const char* other) const
315{
316    String8 tmp(*this);
317    tmp += other;
318    return tmp;
319}
320
321inline int String8::compare(const String8& other) const
322{
323    return strcmp(mString, other.mString);
324}
325
326inline bool String8::operator<(const String8& other) const
327{
328    return strcmp(mString, other.mString) < 0;
329}
330
331inline bool String8::operator<=(const String8& other) const
332{
333    return strcmp(mString, other.mString) <= 0;
334}
335
336inline bool String8::operator==(const String8& other) const
337{
338    return strcmp(mString, other.mString) == 0;
339}
340
341inline bool String8::operator!=(const String8& other) const
342{
343    return strcmp(mString, other.mString) != 0;
344}
345
346inline bool String8::operator>=(const String8& other) const
347{
348    return strcmp(mString, other.mString) >= 0;
349}
350
351inline bool String8::operator>(const String8& other) const
352{
353    return strcmp(mString, other.mString) > 0;
354}
355
356inline bool String8::operator<(const char* other) const
357{
358    return strcmp(mString, other) < 0;
359}
360
361inline bool String8::operator<=(const char* other) const
362{
363    return strcmp(mString, other) <= 0;
364}
365
366inline bool String8::operator==(const char* other) const
367{
368    return strcmp(mString, other) == 0;
369}
370
371inline bool String8::operator!=(const char* other) const
372{
373    return strcmp(mString, other) != 0;
374}
375
376inline bool String8::operator>=(const char* other) const
377{
378    return strcmp(mString, other) >= 0;
379}
380
381inline bool String8::operator>(const char* other) const
382{
383    return strcmp(mString, other) > 0;
384}
385
386inline String8::operator const char*() const
387{
388    return mString;
389}
390
391}  // namespace android
392
393// ---------------------------------------------------------------------------
394
395#endif // ANDROID_STRING8_H
396