1
2 /*
3 * Copyright 2006 The Android Open Source Project
4 *
5 * Use of this source code is governed by a BSD-style license that can be
6 * found in the LICENSE file.
7 */
8
9
10 #ifndef SkString_DEFINED
11 #define SkString_DEFINED
12
13 #include "../private/SkTArray.h"
14 #include "SkScalar.h"
15
16 #include <stdarg.h>
17
18 /* Some helper functions for C strings
19 */
20
SkStrStartsWith(const char string[],const char prefixStr[])21 static bool SkStrStartsWith(const char string[], const char prefixStr[]) {
22 SkASSERT(string);
23 SkASSERT(prefixStr);
24 return !strncmp(string, prefixStr, strlen(prefixStr));
25 }
SkStrStartsWith(const char string[],const char prefixChar)26 static bool SkStrStartsWith(const char string[], const char prefixChar) {
27 SkASSERT(string);
28 return (prefixChar == *string);
29 }
30
31 bool SkStrEndsWith(const char string[], const char suffixStr[]);
32 bool SkStrEndsWith(const char string[], const char suffixChar);
33
34 int SkStrStartsWithOneOf(const char string[], const char prefixes[]);
35
SkStrFind(const char string[],const char substring[])36 static int SkStrFind(const char string[], const char substring[]) {
37 const char *first = strstr(string, substring);
38 if (NULL == first) return -1;
39 return SkToS32(first - &string[0]);
40 }
41
SkStrFindLastOf(const char string[],const char subchar)42 static int SkStrFindLastOf(const char string[], const char subchar) {
43 const char* last = strrchr(string, subchar);
44 if (NULL == last) return -1;
45 return SkToS32(last - &string[0]);
46 }
47
SkStrContains(const char string[],const char substring[])48 static bool SkStrContains(const char string[], const char substring[]) {
49 SkASSERT(string);
50 SkASSERT(substring);
51 return (-1 != SkStrFind(string, substring));
52 }
SkStrContains(const char string[],const char subchar)53 static bool SkStrContains(const char string[], const char subchar) {
54 SkASSERT(string);
55 char tmp[2];
56 tmp[0] = subchar;
57 tmp[1] = '\0';
58 return (-1 != SkStrFind(string, tmp));
59 }
60
SkStrDup(const char string[])61 static inline char *SkStrDup(const char string[]) {
62 char *ret = (char *) sk_malloc_throw(strlen(string)+1);
63 memcpy(ret,string,strlen(string)+1);
64 return ret;
65 }
66
67 /*
68 * The SkStrAppend... methods will write into the provided buffer, assuming it is large enough.
69 * Each method has an associated const (e.g. SkStrAppendU32_MaxSize) which will be the largest
70 * value needed for that method's buffer.
71 *
72 * char storage[SkStrAppendU32_MaxSize];
73 * SkStrAppendU32(storage, value);
74 *
75 * Note : none of the SkStrAppend... methods write a terminating 0 to their buffers. Instead,
76 * the methods return the ptr to the end of the written part of the buffer. This can be used
77 * to compute the length, and/or know where to write a 0 if that is desired.
78 *
79 * char storage[SkStrAppendU32_MaxSize + 1];
80 * char* stop = SkStrAppendU32(storage, value);
81 * size_t len = stop - storage;
82 * *stop = 0; // valid, since storage was 1 byte larger than the max.
83 */
84
85 #define SkStrAppendU32_MaxSize 10
86 char* SkStrAppendU32(char buffer[], uint32_t);
87 #define SkStrAppendU64_MaxSize 20
88 char* SkStrAppendU64(char buffer[], uint64_t, int minDigits);
89
90 #define SkStrAppendS32_MaxSize (SkStrAppendU32_MaxSize + 1)
91 char* SkStrAppendS32(char buffer[], int32_t);
92 #define SkStrAppendS64_MaxSize (SkStrAppendU64_MaxSize + 1)
93 char* SkStrAppendS64(char buffer[], int64_t, int minDigits);
94
95 /**
96 * Floats have at most 8 significant digits, so we limit our %g to that.
97 * However, the total string could be 15 characters: -1.2345678e-005
98 *
99 * In theory we should only expect up to 2 digits for the exponent, but on
100 * some platforms we have seen 3 (as in the example above).
101 */
102 #define SkStrAppendScalar_MaxSize 15
103
104 /**
105 * Write the scaler in decimal format into buffer, and return a pointer to
106 * the next char after the last one written. Note: a terminating 0 is not
107 * written into buffer, which must be at least SkStrAppendScalar_MaxSize.
108 * Thus if the caller wants to add a 0 at the end, buffer must be at least
109 * SkStrAppendScalar_MaxSize + 1 bytes large.
110 */
111 #define SkStrAppendScalar SkStrAppendFloat
112
113 char* SkStrAppendFloat(char buffer[], float);
114 char* SkStrAppendFixed(char buffer[], SkFixed);
115
116 /** \class SkString
117
118 Light weight class for managing strings. Uses reference
119 counting to make string assignments and copies very fast
120 with no extra RAM cost. Assumes UTF8 encoding.
121 */
122 class SK_API SkString {
123 public:
124 SkString();
125 explicit SkString(size_t len);
126 explicit SkString(const char text[]);
127 SkString(const char text[], size_t len);
128 SkString(const SkString&);
129 SkString(SkString&&);
130 ~SkString();
131
isEmpty()132 bool isEmpty() const { return 0 == fRec->fLength; }
size()133 size_t size() const { return (size_t) fRec->fLength; }
c_str()134 const char* c_str() const { return fRec->data(); }
135 char operator[](size_t n) const { return this->c_str()[n]; }
136
137 bool equals(const SkString&) const;
138 bool equals(const char text[]) const;
139 bool equals(const char text[], size_t len) const;
140
startsWith(const char prefixStr[])141 bool startsWith(const char prefixStr[]) const {
142 return SkStrStartsWith(fRec->data(), prefixStr);
143 }
startsWith(const char prefixChar)144 bool startsWith(const char prefixChar) const {
145 return SkStrStartsWith(fRec->data(), prefixChar);
146 }
endsWith(const char suffixStr[])147 bool endsWith(const char suffixStr[]) const {
148 return SkStrEndsWith(fRec->data(), suffixStr);
149 }
endsWith(const char suffixChar)150 bool endsWith(const char suffixChar) const {
151 return SkStrEndsWith(fRec->data(), suffixChar);
152 }
contains(const char substring[])153 bool contains(const char substring[]) const {
154 return SkStrContains(fRec->data(), substring);
155 }
contains(const char subchar)156 bool contains(const char subchar) const {
157 return SkStrContains(fRec->data(), subchar);
158 }
find(const char substring[])159 int find(const char substring[]) const {
160 return SkStrFind(fRec->data(), substring);
161 }
findLastOf(const char subchar)162 int findLastOf(const char subchar) const {
163 return SkStrFindLastOf(fRec->data(), subchar);
164 }
165
166 friend bool operator==(const SkString& a, const SkString& b) {
167 return a.equals(b);
168 }
169 friend bool operator!=(const SkString& a, const SkString& b) {
170 return !a.equals(b);
171 }
172
173 // these methods edit the string
174
175 SkString& operator=(const SkString&);
176 SkString& operator=(SkString&&);
177 SkString& operator=(const char text[]);
178
179 char* writable_str();
180 char& operator[](size_t n) { return this->writable_str()[n]; }
181
182 void reset();
183 /** Destructive resize, does not preserve contents. */
resize(size_t len)184 void resize(size_t len) { this->set(NULL, len); }
set(const SkString & src)185 void set(const SkString& src) { *this = src; }
186 void set(const char text[]);
187 void set(const char text[], size_t len);
188 void setUTF16(const uint16_t[]);
189 void setUTF16(const uint16_t[], size_t len);
190
insert(size_t offset,const SkString & src)191 void insert(size_t offset, const SkString& src) { this->insert(offset, src.c_str(), src.size()); }
192 void insert(size_t offset, const char text[]);
193 void insert(size_t offset, const char text[], size_t len);
194 void insertUnichar(size_t offset, SkUnichar);
195 void insertS32(size_t offset, int32_t value);
196 void insertS64(size_t offset, int64_t value, int minDigits = 0);
197 void insertU32(size_t offset, uint32_t value);
198 void insertU64(size_t offset, uint64_t value, int minDigits = 0);
199 void insertHex(size_t offset, uint32_t value, int minDigits = 0);
200 void insertScalar(size_t offset, SkScalar);
201
append(const SkString & str)202 void append(const SkString& str) { this->insert((size_t)-1, str); }
append(const char text[])203 void append(const char text[]) { this->insert((size_t)-1, text); }
append(const char text[],size_t len)204 void append(const char text[], size_t len) { this->insert((size_t)-1, text, len); }
appendUnichar(SkUnichar uni)205 void appendUnichar(SkUnichar uni) { this->insertUnichar((size_t)-1, uni); }
appendS32(int32_t value)206 void appendS32(int32_t value) { this->insertS32((size_t)-1, value); }
207 void appendS64(int64_t value, int minDigits = 0) { this->insertS64((size_t)-1, value, minDigits); }
appendU32(uint32_t value)208 void appendU32(uint32_t value) { this->insertU32((size_t)-1, value); }
209 void appendU64(uint64_t value, int minDigits = 0) { this->insertU64((size_t)-1, value, minDigits); }
210 void appendHex(uint32_t value, int minDigits = 0) { this->insertHex((size_t)-1, value, minDigits); }
appendScalar(SkScalar value)211 void appendScalar(SkScalar value) { this->insertScalar((size_t)-1, value); }
212
prepend(const SkString & str)213 void prepend(const SkString& str) { this->insert(0, str); }
prepend(const char text[])214 void prepend(const char text[]) { this->insert(0, text); }
prepend(const char text[],size_t len)215 void prepend(const char text[], size_t len) { this->insert(0, text, len); }
prependUnichar(SkUnichar uni)216 void prependUnichar(SkUnichar uni) { this->insertUnichar(0, uni); }
prependS32(int32_t value)217 void prependS32(int32_t value) { this->insertS32(0, value); }
218 void prependS64(int32_t value, int minDigits = 0) { this->insertS64(0, value, minDigits); }
219 void prependHex(uint32_t value, int minDigits = 0) { this->insertHex(0, value, minDigits); }
prependScalar(SkScalar value)220 void prependScalar(SkScalar value) { this->insertScalar((size_t)-1, value); }
221
222 void printf(const char format[], ...) SK_PRINTF_LIKE(2, 3);
223 void appendf(const char format[], ...) SK_PRINTF_LIKE(2, 3);
224 void appendVAList(const char format[], va_list);
225 void prependf(const char format[], ...) SK_PRINTF_LIKE(2, 3);
226 void prependVAList(const char format[], va_list);
227
228 void remove(size_t offset, size_t length);
229
230 SkString& operator+=(const SkString& s) { this->append(s); return *this; }
231 SkString& operator+=(const char text[]) { this->append(text); return *this; }
232 SkString& operator+=(const char c) { this->append(&c, 1); return *this; }
233
234 /**
235 * Swap contents between this and other. This function is guaranteed
236 * to never fail or throw.
237 */
238 void swap(SkString& other);
239
240 private:
241 struct Rec {
242 public:
243 uint32_t fLength; // logically size_t, but we want it to stay 32bits
244 int32_t fRefCnt;
245 char fBeginningOfData;
246
dataRec247 char* data() { return &fBeginningOfData; }
dataRec248 const char* data() const { return &fBeginningOfData; }
249 };
250 Rec* fRec;
251
252 #ifdef SK_DEBUG
253 void validate() const;
254 #else
validate()255 void validate() const {}
256 #endif
257
258 static const Rec gEmptyRec;
259 static Rec* AllocRec(const char text[], size_t len);
260 static Rec* RefRec(Rec*);
261 };
262
263 /// Creates a new string and writes into it using a printf()-style format.
264 SkString SkStringPrintf(const char* format, ...);
265
266 // Specialized to take advantage of SkString's fast swap path. The unspecialized function is
267 // declared in SkTypes.h and called by SkTSort.
SkTSwap(SkString & a,SkString & b)268 template <> inline void SkTSwap(SkString& a, SkString& b) {
269 a.swap(b);
270 }
271
272 enum SkStrSplitMode {
273 // Strictly return all results. If the input is ",," and the separator is ',' this will return
274 // an array of three empty strings.
275 kStrict_SkStrSplitMode,
276
277 // Only nonempty results will be added to the results. Multiple separators will be
278 // coalesced. Separators at the beginning and end of the input will be ignored. If the input is
279 // ",," and the separator is ',', this will return an empty vector.
280 kCoalesce_SkStrSplitMode
281 };
282
283 // Split str on any characters in delimiters into out. (Think, strtok with a sane API.)
284 void SkStrSplit(const char* str, const char* delimiters, SkStrSplitMode splitMode,
285 SkTArray<SkString>* out);
SkStrSplit(const char * str,const char * delimiters,SkTArray<SkString> * out)286 inline void SkStrSplit(const char* str, const char* delimiters, SkTArray<SkString>* out) {
287 SkStrSplit(str, delimiters, kCoalesce_SkStrSplitMode, out);
288 }
289
290 #endif
291