String8.h revision 23b4a0936f1ee11e587b7be9dc3bcae5b55d31cf 
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
22// Need this for the char16_t type; String8.h should not
23// be depedent on the String16 class.
24#include <utils/String16.h>
25
26#include <stdint.h>
27#include <string.h>
28#include <sys/types.h>
29
30// ---------------------------------------------------------------------------
31
32extern "C" {
33
34typedef uint32_t char32_t;
35
36size_t strlen32(const char32_t *);
37size_t strnlen32(const char32_t *, size_t);
38
39/*
40 * Returns the length of "src" when "src" is valid UTF-8 string.
41 * Returns 0 if src is NULL, 0-length string or non UTF-8 string.
42 * This function should be used to determine whether "src" is valid UTF-8
43 * characters with valid unicode codepoints. "src" must be null-terminated.
44 *
45 * If you are going to use other GetUtf... functions defined in this header
46 * with string which may not be valid UTF-8 with valid codepoint (form 0 to
47 * 0x10FFFF), you should use this function before calling others, since the
48 * other functions do not check whether the string is valid UTF-8 or not.
49 *
50 * If you do not care whether "src" is valid UTF-8 or not, you should use
51 * strlen() as usual, which should be much faster.
52 */
53size_t utf8_length(const char *src);
54
55/*
56 * Returns the UTF-32 length of "src".
57 */
58size_t utf32_length(const char *src, size_t src_len);
59
60/*
61 * Returns the UTF-8 length of "src".
62 */
63size_t utf8_length_from_utf16(const char16_t *src, size_t src_len);
64
65/*
66 * Returns the UTF-8 length of "src".
67 */
68size_t utf8_length_from_utf32(const char32_t *src, size_t src_len);
69
70/*
71 * Returns the unicode value at "index".
72 * Returns -1 when the index is invalid (equals to or more than "src_len").
73 * If returned value is positive, it is able to be converted to char32_t, which
74 * is unsigned. Then, if "next_index" is not NULL, the next index to be used is
75 * stored in "next_index". "next_index" can be NULL.
76 */
77int32_t utf32_at(const char *src, size_t src_len,
78                 size_t index, size_t *next_index);
79
80/*
81 * Stores a UTF-32 string converted from "src" in "dst", if "dst_length" is not
82 * large enough to store the string, the part of the "src" string is stored
83 * into "dst".
84 * Returns the size actually used for storing the string.
85 * "dst" is not null-terminated when dst_len is fully used (like strncpy).
86 */
87size_t utf8_to_utf32(const char* src, size_t src_len,
88                     char32_t* dst, size_t dst_len);
89
90/*
91 * Stores a UTF-8 string converted from "src" in "dst", if "dst_length" is not
92 * large enough to store the string, the part of the "src" string is stored
93 * into "dst" as much as possible. See the examples for more detail.
94 * Returns the size actually used for storing the string.
95 * dst" is not null-terminated when dst_len is fully used (like strncpy).
96 *
97 * Example 1
98 * "src" == \u3042\u3044 (\xE3\x81\x82\xE3\x81\x84)
99 * "src_len" == 2
100 * "dst_len" >= 7
101 * ->
102 * Returned value == 6
103 * "dst" becomes \xE3\x81\x82\xE3\x81\x84\0
104 * (note that "dst" is null-terminated)
105 *
106 * Example 2
107 * "src" == \u3042\u3044 (\xE3\x81\x82\xE3\x81\x84)
108 * "src_len" == 2
109 * "dst_len" == 5
110 * ->
111 * Returned value == 3
112 * "dst" becomes \xE3\x81\x82\0
113 * (note that "dst" is null-terminated, but \u3044 is not stored in "dst"
114 * since "dst" does not have enough size to store the character)
115 *
116 * Example 3
117 * "src" == \u3042\u3044 (\xE3\x81\x82\xE3\x81\x84)
118 * "src_len" == 2
119 * "dst_len" == 6
120 * ->
121 * Returned value == 6
122 * "dst" becomes \xE3\x81\x82\xE3\x81\x84
123 * (note that "dst" is NOT null-terminated, like strncpy)
124 */
125size_t utf32_to_utf8(const char32_t* src, size_t src_len,
126                     char* dst, size_t dst_len);
127
128size_t utf16_to_utf8(const char16_t* src, size_t src_len,
129                     char* dst, size_t dst_len);
130
131}
132
133// ---------------------------------------------------------------------------
134
135namespace android {
136
137class TextOutput;
138
139//! This is a string holding UTF-8 characters. Does not allow the value more
140// than 0x10FFFF, which is not valid unicode codepoint.
141class String8
142{
143public:
144                                String8();
145                                String8(const String8& o);
146    explicit                    String8(const char* o);
147    explicit                    String8(const char* o, size_t numChars);
148
149    explicit                    String8(const String16& o);
150    explicit                    String8(const char16_t* o);
151    explicit                    String8(const char16_t* o, size_t numChars);
152    explicit                    String8(const char32_t* o);
153    explicit                    String8(const char32_t* o, size_t numChars);
154                                ~String8();
155
156    inline  const char*         string() const;
157    inline  size_t              size() const;
158    inline  size_t              length() const;
159    inline  size_t              bytes() const;
160
161    inline  const SharedBuffer* sharedBuffer() const;
162
163            void                setTo(const String8& other);
164            status_t            setTo(const char* other);
165            status_t            setTo(const char* other, size_t numChars);
166            status_t            setTo(const char16_t* other, size_t numChars);
167            status_t            setTo(const char32_t* other,
168                                      size_t length);
169
170            status_t            append(const String8& other);
171            status_t            append(const char* other);
172            status_t            append(const char* other, size_t numChars);
173
174            status_t            appendFormat(const char* fmt, ...);
175
176            // Note that this function takes O(N) time to calculate the value.
177            // No cache value is stored.
178            size_t              getUtf32Length() const;
179            int32_t             getUtf32At(size_t index,
180                                           size_t *next_index) const;
181            size_t              getUtf32(char32_t* dst, size_t dst_len) const;
182
183    inline  String8&            operator=(const String8& other);
184    inline  String8&            operator=(const char* other);
185
186    inline  String8&            operator+=(const String8& other);
187    inline  String8             operator+(const String8& other) const;
188
189    inline  String8&            operator+=(const char* other);
190    inline  String8             operator+(const char* other) const;
191
192    inline  int                 compare(const String8& other) const;
193
194    inline  bool                operator<(const String8& other) const;
195    inline  bool                operator<=(const String8& other) const;
196    inline  bool                operator==(const String8& other) const;
197    inline  bool                operator!=(const String8& other) const;
198    inline  bool                operator>=(const String8& other) const;
199    inline  bool                operator>(const String8& other) const;
200
201    inline  bool                operator<(const char* other) const;
202    inline  bool                operator<=(const char* other) const;
203    inline  bool                operator==(const char* other) const;
204    inline  bool                operator!=(const char* other) const;
205    inline  bool                operator>=(const char* other) const;
206    inline  bool                operator>(const char* other) const;
207
208    inline                      operator const char*() const;
209
210            char*               lockBuffer(size_t size);
211            void                unlockBuffer();
212            status_t            unlockBuffer(size_t size);
213
214            // return the index of the first byte of other in this at or after
215            // start, or -1 if not found
216            ssize_t             find(const char* other, size_t start = 0) const;
217
218            void                toLower();
219            void                toLower(size_t start, size_t numChars);
220            void                toUpper();
221            void                toUpper(size_t start, size_t numChars);
222
223    /*
224     * These methods operate on the string as if it were a path name.
225     */
226
227    /*
228     * Set the filename field to a specific value.
229     *
230     * Normalizes the filename, removing a trailing '/' if present.
231     */
232    void setPathName(const char* name);
233    void setPathName(const char* name, size_t numChars);
234
235    /*
236     * Get just the filename component.
237     *
238     * "/tmp/foo/bar.c" --> "bar.c"
239     */
240    String8 getPathLeaf(void) const;
241
242    /*
243     * Remove the last (file name) component, leaving just the directory
244     * name.
245     *
246     * "/tmp/foo/bar.c" --> "/tmp/foo"
247     * "/tmp" --> "" // ????? shouldn't this be "/" ???? XXX
248     * "bar.c" --> ""
249     */
250    String8 getPathDir(void) const;
251
252    /*
253     * Retrieve the front (root dir) component.  Optionally also return the
254     * remaining components.
255     *
256     * "/tmp/foo/bar.c" --> "tmp" (remain = "foo/bar.c")
257     * "/tmp" --> "tmp" (remain = "")
258     * "bar.c" --> "bar.c" (remain = "")
259     */
260    String8 walkPath(String8* outRemains = NULL) const;
261
262    /*
263     * Return the filename extension.  This is the last '.' and up to
264     * four characters that follow it.  The '.' is included in case we
265     * decide to expand our definition of what constitutes an extension.
266     *
267     * "/tmp/foo/bar.c" --> ".c"
268     * "/tmp" --> ""
269     * "/tmp/foo.bar/baz" --> ""
270     * "foo.jpeg" --> ".jpeg"
271     * "foo." --> ""
272     */
273    String8 getPathExtension(void) const;
274
275    /*
276     * Return the path without the extension.  Rules for what constitutes
277     * an extension are described in the comment for getPathExtension().
278     *
279     * "/tmp/foo/bar.c" --> "/tmp/foo/bar"
280     */
281    String8 getBasePath(void) const;
282
283    /*
284     * Add a component to the pathname.  We guarantee that there is
285     * exactly one path separator between the old path and the new.
286     * If there is no existing name, we just copy the new name in.
287     *
288     * If leaf is a fully qualified path (i.e. starts with '/', it
289     * replaces whatever was there before.
290     */
291    String8& appendPath(const char* leaf);
292    String8& appendPath(const String8& leaf)  { return appendPath(leaf.string()); }
293
294    /*
295     * Like appendPath(), but does not affect this string.  Returns a new one instead.
296     */
297    String8 appendPathCopy(const char* leaf) const
298                                             { String8 p(*this); p.appendPath(leaf); return p; }
299    String8 appendPathCopy(const String8& leaf) const { return appendPathCopy(leaf.string()); }
300
301    /*
302     * Converts all separators in this string to /, the default path separator.
303     *
304     * If the default OS separator is backslash, this converts all
305     * backslashes to slashes, in-place. Otherwise it does nothing.
306     * Returns self.
307     */
308    String8& convertToResPath();
309
310private:
311            status_t            real_append(const char* other, size_t numChars);
312            char*               find_extension(void) const;
313
314            const char* mString;
315};
316
317TextOutput& operator<<(TextOutput& to, const String16& val);
318
319// ---------------------------------------------------------------------------
320// No user servicable parts below.
321
322inline int compare_type(const String8& lhs, const String8& rhs)
323{
324    return lhs.compare(rhs);
325}
326
327inline int strictly_order_type(const String8& lhs, const String8& rhs)
328{
329    return compare_type(lhs, rhs) < 0;
330}
331
332inline const char* String8::string() const
333{
334    return mString;
335}
336
337inline size_t String8::length() const
338{
339    return SharedBuffer::sizeFromData(mString)-1;
340}
341
342inline size_t String8::size() const
343{
344    return length();
345}
346
347inline size_t String8::bytes() const
348{
349    return SharedBuffer::sizeFromData(mString)-1;
350}
351
352inline const SharedBuffer* String8::sharedBuffer() const
353{
354    return SharedBuffer::bufferFromData(mString);
355}
356
357inline String8& String8::operator=(const String8& other)
358{
359    setTo(other);
360    return *this;
361}
362
363inline String8& String8::operator=(const char* other)
364{
365    setTo(other);
366    return *this;
367}
368
369inline String8& String8::operator+=(const String8& other)
370{
371    append(other);
372    return *this;
373}
374
375inline String8 String8::operator+(const String8& other) const
376{
377    String8 tmp(*this);
378    tmp += other;
379    return tmp;
380}
381
382inline String8& String8::operator+=(const char* other)
383{
384    append(other);
385    return *this;
386}
387
388inline String8 String8::operator+(const char* other) const
389{
390    String8 tmp(*this);
391    tmp += other;
392    return tmp;
393}
394
395inline int String8::compare(const String8& other) const
396{
397    return strcmp(mString, other.mString);
398}
399
400inline bool String8::operator<(const String8& other) const
401{
402    return strcmp(mString, other.mString) < 0;
403}
404
405inline bool String8::operator<=(const String8& other) const
406{
407    return strcmp(mString, other.mString) <= 0;
408}
409
410inline bool String8::operator==(const String8& other) const
411{
412    return strcmp(mString, other.mString) == 0;
413}
414
415inline bool String8::operator!=(const String8& other) const
416{
417    return strcmp(mString, other.mString) != 0;
418}
419
420inline bool String8::operator>=(const String8& other) const
421{
422    return strcmp(mString, other.mString) >= 0;
423}
424
425inline bool String8::operator>(const String8& other) const
426{
427    return strcmp(mString, other.mString) > 0;
428}
429
430inline bool String8::operator<(const char* other) const
431{
432    return strcmp(mString, other) < 0;
433}
434
435inline bool String8::operator<=(const char* other) const
436{
437    return strcmp(mString, other) <= 0;
438}
439
440inline bool String8::operator==(const char* other) const
441{
442    return strcmp(mString, other) == 0;
443}
444
445inline bool String8::operator!=(const char* other) const
446{
447    return strcmp(mString, other) != 0;
448}
449
450inline bool String8::operator>=(const char* other) const
451{
452    return strcmp(mString, other) >= 0;
453}
454
455inline bool String8::operator>(const char* other) const
456{
457    return strcmp(mString, other) > 0;
458}
459
460inline String8::operator const char*() const
461{
462    return mString;
463}
464
465}  // namespace android
466
467// ---------------------------------------------------------------------------
468
469#endif // ANDROID_STRING8_H
470