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 
30 namespace android {
31 
32 class String16;
33 class 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.
37 class String8
38 {
39 public:
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             // return true if this string contains the specified substring
134     inline  bool                contains(const char* other) const;
135 
136             // removes all occurrence of the specified substring
137             // returns true if any were found and removed
138             bool                removeAll(const char* other);
139 
140             void                toLower();
141             void                toLower(size_t start, size_t numChars);
142             void                toUpper();
143             void                toUpper(size_t start, size_t numChars);
144 
145 
146     /*
147      * These methods operate on the string as if it were a path name.
148      */
149 
150     /*
151      * Set the filename field to a specific value.
152      *
153      * Normalizes the filename, removing a trailing '/' if present.
154      */
155     void setPathName(const char* name);
156     void setPathName(const char* name, size_t numChars);
157 
158     /*
159      * Get just the filename component.
160      *
161      * "/tmp/foo/bar.c" --> "bar.c"
162      */
163     String8 getPathLeaf(void) const;
164 
165     /*
166      * Remove the last (file name) component, leaving just the directory
167      * name.
168      *
169      * "/tmp/foo/bar.c" --> "/tmp/foo"
170      * "/tmp" --> "" // ????? shouldn't this be "/" ???? XXX
171      * "bar.c" --> ""
172      */
173     String8 getPathDir(void) const;
174 
175     /*
176      * Retrieve the front (root dir) component.  Optionally also return the
177      * remaining components.
178      *
179      * "/tmp/foo/bar.c" --> "tmp" (remain = "foo/bar.c")
180      * "/tmp" --> "tmp" (remain = "")
181      * "bar.c" --> "bar.c" (remain = "")
182      */
183     String8 walkPath(String8* outRemains = NULL) const;
184 
185     /*
186      * Return the filename extension.  This is the last '.' and any number
187      * of characters that follow it.  The '.' is included in case we
188      * decide to expand our definition of what constitutes an extension.
189      *
190      * "/tmp/foo/bar.c" --> ".c"
191      * "/tmp" --> ""
192      * "/tmp/foo.bar/baz" --> ""
193      * "foo.jpeg" --> ".jpeg"
194      * "foo." --> ""
195      */
196     String8 getPathExtension(void) const;
197 
198     /*
199      * Return the path without the extension.  Rules for what constitutes
200      * an extension are described in the comment for getPathExtension().
201      *
202      * "/tmp/foo/bar.c" --> "/tmp/foo/bar"
203      */
204     String8 getBasePath(void) const;
205 
206     /*
207      * Add a component to the pathname.  We guarantee that there is
208      * exactly one path separator between the old path and the new.
209      * If there is no existing name, we just copy the new name in.
210      *
211      * If leaf is a fully qualified path (i.e. starts with '/', it
212      * replaces whatever was there before.
213      */
214     String8& appendPath(const char* leaf);
appendPath(const String8 & leaf)215     String8& appendPath(const String8& leaf)  { return appendPath(leaf.string()); }
216 
217     /*
218      * Like appendPath(), but does not affect this string.  Returns a new one instead.
219      */
appendPathCopy(const char * leaf)220     String8 appendPathCopy(const char* leaf) const
221                                              { String8 p(*this); p.appendPath(leaf); return p; }
appendPathCopy(const String8 & leaf)222     String8 appendPathCopy(const String8& leaf) const { return appendPathCopy(leaf.string()); }
223 
224     /*
225      * Converts all separators in this string to /, the default path separator.
226      *
227      * If the default OS separator is backslash, this converts all
228      * backslashes to slashes, in-place. Otherwise it does nothing.
229      * Returns self.
230      */
231     String8& convertToResPath();
232 
233 private:
234             status_t            real_append(const char* other, size_t numChars);
235             char*               find_extension(void) const;
236 
237             const char* mString;
238 };
239 
240 // String8 can be trivially moved using memcpy() because moving does not
241 // require any change to the underlying SharedBuffer contents or reference count.
ANDROID_TRIVIAL_MOVE_TRAIT(String8)242 ANDROID_TRIVIAL_MOVE_TRAIT(String8)
243 
244 // ---------------------------------------------------------------------------
245 // No user servicable parts below.
246 
247 inline int compare_type(const String8& lhs, const String8& rhs)
248 {
249     return lhs.compare(rhs);
250 }
251 
strictly_order_type(const String8 & lhs,const String8 & rhs)252 inline int strictly_order_type(const String8& lhs, const String8& rhs)
253 {
254     return compare_type(lhs, rhs) < 0;
255 }
256 
empty()257 inline const String8 String8::empty() {
258     return String8();
259 }
260 
string()261 inline const char* String8::string() const
262 {
263     return mString;
264 }
265 
length()266 inline size_t String8::length() const
267 {
268     return SharedBuffer::sizeFromData(mString)-1;
269 }
270 
size()271 inline size_t String8::size() const
272 {
273     return length();
274 }
275 
isEmpty()276 inline bool String8::isEmpty() const
277 {
278     return length() == 0;
279 }
280 
bytes()281 inline size_t String8::bytes() const
282 {
283     return SharedBuffer::sizeFromData(mString)-1;
284 }
285 
sharedBuffer()286 inline const SharedBuffer* String8::sharedBuffer() const
287 {
288     return SharedBuffer::bufferFromData(mString);
289 }
290 
contains(const char * other)291 inline bool String8::contains(const char* other) const
292 {
293     return find(other) >= 0;
294 }
295 
296 inline String8& String8::operator=(const String8& other)
297 {
298     setTo(other);
299     return *this;
300 }
301 
302 inline String8& String8::operator=(const char* other)
303 {
304     setTo(other);
305     return *this;
306 }
307 
308 inline String8& String8::operator+=(const String8& other)
309 {
310     append(other);
311     return *this;
312 }
313 
314 inline String8 String8::operator+(const String8& other) const
315 {
316     String8 tmp(*this);
317     tmp += other;
318     return tmp;
319 }
320 
321 inline String8& String8::operator+=(const char* other)
322 {
323     append(other);
324     return *this;
325 }
326 
327 inline String8 String8::operator+(const char* other) const
328 {
329     String8 tmp(*this);
330     tmp += other;
331     return tmp;
332 }
333 
compare(const String8 & other)334 inline int String8::compare(const String8& other) const
335 {
336     return strcmp(mString, other.mString);
337 }
338 
339 inline bool String8::operator<(const String8& other) const
340 {
341     return strcmp(mString, other.mString) < 0;
342 }
343 
344 inline bool String8::operator<=(const String8& other) const
345 {
346     return strcmp(mString, other.mString) <= 0;
347 }
348 
349 inline bool String8::operator==(const String8& other) const
350 {
351     return strcmp(mString, other.mString) == 0;
352 }
353 
354 inline bool String8::operator!=(const String8& other) const
355 {
356     return strcmp(mString, other.mString) != 0;
357 }
358 
359 inline bool String8::operator>=(const String8& other) const
360 {
361     return strcmp(mString, other.mString) >= 0;
362 }
363 
364 inline bool String8::operator>(const String8& other) const
365 {
366     return strcmp(mString, other.mString) > 0;
367 }
368 
369 inline bool String8::operator<(const char* other) const
370 {
371     return strcmp(mString, other) < 0;
372 }
373 
374 inline bool String8::operator<=(const char* other) const
375 {
376     return strcmp(mString, other) <= 0;
377 }
378 
379 inline bool String8::operator==(const char* other) const
380 {
381     return strcmp(mString, other) == 0;
382 }
383 
384 inline bool String8::operator!=(const char* other) const
385 {
386     return strcmp(mString, other) != 0;
387 }
388 
389 inline bool String8::operator>=(const char* other) const
390 {
391     return strcmp(mString, other) >= 0;
392 }
393 
394 inline bool String8::operator>(const char* other) const
395 {
396     return strcmp(mString, other) > 0;
397 }
398 
399 inline String8::operator const char*() const
400 {
401     return mString;
402 }
403 
404 }  // namespace android
405 
406 // ---------------------------------------------------------------------------
407 
408 #endif // ANDROID_STRING8_H
409