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 #include <utils/String16.h>
18 
19 #include <utils/Log.h>
20 
21 #include <ctype.h>
22 
23 #include "SharedBuffer.h"
24 
25 namespace android {
26 
27 static const StaticString16 emptyString(u"");
getEmptyString()28 static inline char16_t* getEmptyString() {
29     return const_cast<char16_t*>(emptyString.string());
30 }
31 
32 // ---------------------------------------------------------------------------
33 
alloc(size_t size)34 void* String16::alloc(size_t size)
35 {
36     SharedBuffer* buf = SharedBuffer::alloc(size);
37     buf->mClientMetadata = kIsSharedBufferAllocated;
38     return buf;
39 }
40 
allocFromUTF8(const char * u8str,size_t u8len)41 char16_t* String16::allocFromUTF8(const char* u8str, size_t u8len)
42 {
43     if (u8len == 0) return getEmptyString();
44 
45     const uint8_t* u8cur = (const uint8_t*) u8str;
46 
47     const ssize_t u16len = utf8_to_utf16_length(u8cur, u8len);
48     if (u16len < 0) {
49         return getEmptyString();
50     }
51 
52     SharedBuffer* buf = static_cast<SharedBuffer*>(alloc(sizeof(char16_t) * (u16len + 1)));
53     if (buf) {
54         u8cur = (const uint8_t*) u8str;
55         char16_t* u16str = (char16_t*)buf->data();
56 
57         utf8_to_utf16(u8cur, u8len, u16str, ((size_t) u16len) + 1);
58 
59         //printf("Created UTF-16 string from UTF-8 \"%s\":", in);
60         //printHexData(1, str, buf->size(), 16, 1);
61         //printf("\n");
62 
63         return u16str;
64     }
65 
66     return getEmptyString();
67 }
68 
allocFromUTF16(const char16_t * u16str,size_t u16len)69 char16_t* String16::allocFromUTF16(const char16_t* u16str, size_t u16len) {
70     if (u16len >= SIZE_MAX / sizeof(char16_t)) {
71         android_errorWriteLog(0x534e4554, "73826242");
72         abort();
73     }
74 
75     SharedBuffer* buf = static_cast<SharedBuffer*>(alloc((u16len + 1) * sizeof(char16_t)));
76     ALOG_ASSERT(buf, "Unable to allocate shared buffer");
77     if (buf) {
78         char16_t* str = (char16_t*)buf->data();
79         memcpy(str, u16str, u16len * sizeof(char16_t));
80         str[u16len] = 0;
81         return str;
82     }
83     return getEmptyString();
84 }
85 
86 // ---------------------------------------------------------------------------
87 
String16()88 String16::String16()
89     : mString(getEmptyString())
90 {
91 }
92 
String16(const String16 & o)93 String16::String16(const String16& o)
94     : mString(o.mString)
95 {
96     acquire();
97 }
98 
String16(const String16 & o,size_t len,size_t begin)99 String16::String16(const String16& o, size_t len, size_t begin)
100     : mString(getEmptyString())
101 {
102     setTo(o, len, begin);
103 }
104 
String16(const char16_t * o)105 String16::String16(const char16_t* o) : mString(allocFromUTF16(o, strlen16(o))) {}
106 
String16(const char16_t * o,size_t len)107 String16::String16(const char16_t* o, size_t len) : mString(allocFromUTF16(o, len)) {}
108 
String16(const String8 & o)109 String16::String16(const String8& o)
110     : mString(allocFromUTF8(o.string(), o.size()))
111 {
112 }
113 
String16(const char * o)114 String16::String16(const char* o)
115     : mString(allocFromUTF8(o, strlen(o)))
116 {
117 }
118 
String16(const char * o,size_t len)119 String16::String16(const char* o, size_t len)
120     : mString(allocFromUTF8(o, len))
121 {
122 }
123 
~String16()124 String16::~String16()
125 {
126     release();
127 }
128 
size() const129 size_t String16::size() const
130 {
131     if (isStaticString()) {
132         return staticStringSize();
133     } else {
134         return SharedBuffer::sizeFromData(mString) / sizeof(char16_t) - 1;
135     }
136 }
137 
setTo(const String16 & other)138 void String16::setTo(const String16& other)
139 {
140     release();
141     mString = other.mString;
142     acquire();
143 }
144 
setTo(const String16 & other,size_t len,size_t begin)145 status_t String16::setTo(const String16& other, size_t len, size_t begin)
146 {
147     const size_t N = other.size();
148     if (begin >= N) {
149         release();
150         mString = getEmptyString();
151         return OK;
152     }
153     if ((begin+len) > N) len = N-begin;
154     if (begin == 0 && len == N) {
155         setTo(other);
156         return OK;
157     }
158 
159     if (&other == this) {
160         LOG_ALWAYS_FATAL("Not implemented");
161     }
162 
163     return setTo(other.string()+begin, len);
164 }
165 
setTo(const char16_t * other)166 status_t String16::setTo(const char16_t* other)
167 {
168     return setTo(other, strlen16(other));
169 }
170 
setTo(const char16_t * other,size_t len)171 status_t String16::setTo(const char16_t* other, size_t len)
172 {
173     if (len >= SIZE_MAX / sizeof(char16_t)) {
174         android_errorWriteLog(0x534e4554, "73826242");
175         abort();
176     }
177 
178     SharedBuffer* buf = static_cast<SharedBuffer*>(editResize((len + 1) * sizeof(char16_t)));
179     if (buf) {
180         char16_t* str = (char16_t*)buf->data();
181         memmove(str, other, len*sizeof(char16_t));
182         str[len] = 0;
183         mString = str;
184         return OK;
185     }
186     return NO_MEMORY;
187 }
188 
append(const String16 & other)189 status_t String16::append(const String16& other)
190 {
191     const size_t myLen = size();
192     const size_t otherLen = other.size();
193     if (myLen == 0) {
194         setTo(other);
195         return OK;
196     } else if (otherLen == 0) {
197         return OK;
198     }
199 
200     if (myLen >= SIZE_MAX / sizeof(char16_t) - otherLen) {
201         android_errorWriteLog(0x534e4554, "73826242");
202         abort();
203     }
204 
205     SharedBuffer* buf =
206             static_cast<SharedBuffer*>(editResize((myLen + otherLen + 1) * sizeof(char16_t)));
207     if (buf) {
208         char16_t* str = (char16_t*)buf->data();
209         memcpy(str+myLen, other, (otherLen+1)*sizeof(char16_t));
210         mString = str;
211         return OK;
212     }
213     return NO_MEMORY;
214 }
215 
append(const char16_t * chrs,size_t otherLen)216 status_t String16::append(const char16_t* chrs, size_t otherLen)
217 {
218     const size_t myLen = size();
219     if (myLen == 0) {
220         setTo(chrs, otherLen);
221         return OK;
222     } else if (otherLen == 0) {
223         return OK;
224     }
225 
226     if (myLen >= SIZE_MAX / sizeof(char16_t) - otherLen) {
227         android_errorWriteLog(0x534e4554, "73826242");
228         abort();
229     }
230 
231     SharedBuffer* buf =
232             static_cast<SharedBuffer*>(editResize((myLen + otherLen + 1) * sizeof(char16_t)));
233     if (buf) {
234         char16_t* str = (char16_t*)buf->data();
235         memcpy(str+myLen, chrs, otherLen*sizeof(char16_t));
236         str[myLen+otherLen] = 0;
237         mString = str;
238         return OK;
239     }
240     return NO_MEMORY;
241 }
242 
insert(size_t pos,const char16_t * chrs)243 status_t String16::insert(size_t pos, const char16_t* chrs)
244 {
245     return insert(pos, chrs, strlen16(chrs));
246 }
247 
insert(size_t pos,const char16_t * chrs,size_t len)248 status_t String16::insert(size_t pos, const char16_t* chrs, size_t len)
249 {
250     const size_t myLen = size();
251     if (myLen == 0) {
252         return setTo(chrs, len);
253         return OK;
254     } else if (len == 0) {
255         return OK;
256     }
257 
258     if (pos > myLen) pos = myLen;
259 
260     #if 0
261     printf("Insert in to %s: pos=%d, len=%d, myLen=%d, chrs=%s\n",
262            String8(*this).string(), pos,
263            len, myLen, String8(chrs, len).string());
264     #endif
265 
266     SharedBuffer* buf =
267             static_cast<SharedBuffer*>(editResize((myLen + len + 1) * sizeof(char16_t)));
268     if (buf) {
269         char16_t* str = (char16_t*)buf->data();
270         if (pos < myLen) {
271             memmove(str+pos+len, str+pos, (myLen-pos)*sizeof(char16_t));
272         }
273         memcpy(str+pos, chrs, len*sizeof(char16_t));
274         str[myLen+len] = 0;
275         mString = str;
276         #if 0
277         printf("Result (%d chrs): %s\n", size(), String8(*this).string());
278         #endif
279         return OK;
280     }
281     return NO_MEMORY;
282 }
283 
findFirst(char16_t c) const284 ssize_t String16::findFirst(char16_t c) const
285 {
286     const char16_t* str = string();
287     const char16_t* p = str;
288     const char16_t* e = p + size();
289     while (p < e) {
290         if (*p == c) {
291             return p-str;
292         }
293         p++;
294     }
295     return -1;
296 }
297 
findLast(char16_t c) const298 ssize_t String16::findLast(char16_t c) const
299 {
300     const char16_t* str = string();
301     const char16_t* p = str;
302     const char16_t* e = p + size();
303     while (p < e) {
304         e--;
305         if (*e == c) {
306             return e-str;
307         }
308     }
309     return -1;
310 }
311 
startsWith(const String16 & prefix) const312 bool String16::startsWith(const String16& prefix) const
313 {
314     const size_t ps = prefix.size();
315     if (ps > size()) return false;
316     return strzcmp16(mString, ps, prefix.string(), ps) == 0;
317 }
318 
startsWith(const char16_t * prefix) const319 bool String16::startsWith(const char16_t* prefix) const
320 {
321     const size_t ps = strlen16(prefix);
322     if (ps > size()) return false;
323     return strncmp16(mString, prefix, ps) == 0;
324 }
325 
contains(const char16_t * chrs) const326 bool String16::contains(const char16_t* chrs) const
327 {
328     return strstr16(mString, chrs) != nullptr;
329 }
330 
edit()331 void* String16::edit() {
332     SharedBuffer* buf;
333     if (isStaticString()) {
334         buf = static_cast<SharedBuffer*>(alloc((size() + 1) * sizeof(char16_t)));
335         if (buf) {
336             memcpy(buf->data(), mString, (size() + 1) * sizeof(char16_t));
337         }
338     } else {
339         buf = SharedBuffer::bufferFromData(mString)->edit();
340         buf->mClientMetadata = kIsSharedBufferAllocated;
341     }
342     return buf;
343 }
344 
editResize(size_t newSize)345 void* String16::editResize(size_t newSize) {
346     SharedBuffer* buf;
347     if (isStaticString()) {
348         size_t copySize = (size() + 1) * sizeof(char16_t);
349         if (newSize < copySize) {
350             copySize = newSize;
351         }
352         buf = static_cast<SharedBuffer*>(alloc(newSize));
353         if (buf) {
354             memcpy(buf->data(), mString, copySize);
355         }
356     } else {
357         buf = SharedBuffer::bufferFromData(mString)->editResize(newSize);
358         buf->mClientMetadata = kIsSharedBufferAllocated;
359     }
360     return buf;
361 }
362 
acquire()363 void String16::acquire()
364 {
365     if (!isStaticString()) {
366         SharedBuffer::bufferFromData(mString)->acquire();
367     }
368 }
369 
release()370 void String16::release()
371 {
372     if (!isStaticString()) {
373         SharedBuffer::bufferFromData(mString)->release();
374     }
375 }
376 
isStaticString() const377 bool String16::isStaticString() const {
378     // See String16.h for notes on the memory layout of String16::StaticData and
379     // SharedBuffer.
380     static_assert(sizeof(SharedBuffer) - offsetof(SharedBuffer, mClientMetadata) == 4);
381     const uint32_t* p = reinterpret_cast<const uint32_t*>(mString);
382     return (*(p - 1) & kIsSharedBufferAllocated) == 0;
383 }
384 
staticStringSize() const385 size_t String16::staticStringSize() const {
386     // See String16.h for notes on the memory layout of String16::StaticData and
387     // SharedBuffer.
388     static_assert(sizeof(SharedBuffer) - offsetof(SharedBuffer, mClientMetadata) == 4);
389     const uint32_t* p = reinterpret_cast<const uint32_t*>(mString);
390     return static_cast<size_t>(*(p - 1));
391 }
392 
makeLower()393 status_t String16::makeLower()
394 {
395     const size_t N = size();
396     const char16_t* str = string();
397     char16_t* edited = nullptr;
398     for (size_t i=0; i<N; i++) {
399         const char16_t v = str[i];
400         if (v >= 'A' && v <= 'Z') {
401             if (!edited) {
402                 SharedBuffer* buf = static_cast<SharedBuffer*>(edit());
403                 if (!buf) {
404                     return NO_MEMORY;
405                 }
406                 edited = (char16_t*)buf->data();
407                 mString = str = edited;
408             }
409             edited[i] = tolower((char)v);
410         }
411     }
412     return OK;
413 }
414 
replaceAll(char16_t replaceThis,char16_t withThis)415 status_t String16::replaceAll(char16_t replaceThis, char16_t withThis)
416 {
417     const size_t N = size();
418     const char16_t* str = string();
419     char16_t* edited = nullptr;
420     for (size_t i=0; i<N; i++) {
421         if (str[i] == replaceThis) {
422             if (!edited) {
423                 SharedBuffer* buf = static_cast<SharedBuffer*>(edit());
424                 if (!buf) {
425                     return NO_MEMORY;
426                 }
427                 edited = (char16_t*)buf->data();
428                 mString = str = edited;
429             }
430             edited[i] = withThis;
431         }
432     }
433     return OK;
434 }
435 
remove(size_t len,size_t begin)436 status_t String16::remove(size_t len, size_t begin)
437 {
438     const size_t N = size();
439     if (begin >= N) {
440         release();
441         mString = getEmptyString();
442         return OK;
443     }
444     if ((begin+len) > N) len = N-begin;
445     if (begin == 0 && len == N) {
446         return OK;
447     }
448 
449     if (begin > 0) {
450         SharedBuffer* buf = static_cast<SharedBuffer*>(editResize((N + 1) * sizeof(char16_t)));
451         if (!buf) {
452             return NO_MEMORY;
453         }
454         char16_t* str = (char16_t*)buf->data();
455         memmove(str, str+begin, (N-begin+1)*sizeof(char16_t));
456         mString = str;
457     }
458     SharedBuffer* buf = static_cast<SharedBuffer*>(editResize((len + 1) * sizeof(char16_t)));
459     if (buf) {
460         char16_t* str = (char16_t*)buf->data();
461         str[len] = 0;
462         mString = str;
463         return OK;
464     }
465     return NO_MEMORY;
466 }
467 
468 }; // namespace android
469