aboutsummaryrefslogtreecommitdiffhomepage
path: root/include/core/SkString.h
blob: 621c66114287d679e5e26705e097334a904d95ed (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289

/*
 * Copyright 2006 The Android Open Source Project
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */


#ifndef SkString_DEFINED
#define SkString_DEFINED

#include "../private/SkTArray.h"
#include "SkScalar.h"

#include <stdarg.h>

/*  Some helper functions for C strings
*/

static bool SkStrStartsWith(const char string[], const char prefixStr[]) {
    SkASSERT(string);
    SkASSERT(prefixStr);
    return !strncmp(string, prefixStr, strlen(prefixStr));
}
static bool SkStrStartsWith(const char string[], const char prefixChar) {
    SkASSERT(string);
    return (prefixChar == *string);
}

bool SkStrEndsWith(const char string[], const char suffixStr[]);
bool SkStrEndsWith(const char string[], const char suffixChar);

int SkStrStartsWithOneOf(const char string[], const char prefixes[]);

static int SkStrFind(const char string[], const char substring[]) {
    const char *first = strstr(string, substring);
    if (nullptr == first) return -1;
    return SkToInt(first - &string[0]);
}

static int SkStrFindLastOf(const char string[], const char subchar) {
    const char* last = strrchr(string, subchar);
    if (nullptr == last) return -1;
    return SkToInt(last - &string[0]);
}

static bool SkStrContains(const char string[], const char substring[]) {
    SkASSERT(string);
    SkASSERT(substring);
    return (-1 != SkStrFind(string, substring));
}
static bool SkStrContains(const char string[], const char subchar) {
    SkASSERT(string);
    char tmp[2];
    tmp[0] = subchar;
    tmp[1] = '\0';
    return (-1 != SkStrFind(string, tmp));
}

static inline char *SkStrDup(const char string[]) {
    char *ret = (char *) sk_malloc_throw(strlen(string)+1);
    memcpy(ret,string,strlen(string)+1);
    return ret;
}

/*
 *  The SkStrAppend... methods will write into the provided buffer, assuming it is large enough.
 *  Each method has an associated const (e.g. SkStrAppendU32_MaxSize) which will be the largest
 *  value needed for that method's buffer.
 *
 *  char storage[SkStrAppendU32_MaxSize];
 *  SkStrAppendU32(storage, value);
 *
 *  Note : none of the SkStrAppend... methods write a terminating 0 to their buffers. Instead,
 *  the methods return the ptr to the end of the written part of the buffer. This can be used
 *  to compute the length, and/or know where to write a 0 if that is desired.
 *
 *  char storage[SkStrAppendU32_MaxSize + 1];
 *  char* stop = SkStrAppendU32(storage, value);
 *  size_t len = stop - storage;
 *  *stop = 0;   // valid, since storage was 1 byte larger than the max.
 */

#define SkStrAppendU32_MaxSize  10
char*   SkStrAppendU32(char buffer[], uint32_t);
#define SkStrAppendU64_MaxSize  20
char*   SkStrAppendU64(char buffer[], uint64_t, int minDigits);

#define SkStrAppendS32_MaxSize  (SkStrAppendU32_MaxSize + 1)
char*   SkStrAppendS32(char buffer[], int32_t);
#define SkStrAppendS64_MaxSize  (SkStrAppendU64_MaxSize + 1)
char*   SkStrAppendS64(char buffer[], int64_t, int minDigits);

/**
 *  Floats have at most 8 significant digits, so we limit our %g to that.
 *  However, the total string could be 15 characters: -1.2345678e-005
 *
 *  In theory we should only expect up to 2 digits for the exponent, but on
 *  some platforms we have seen 3 (as in the example above).
 */
#define SkStrAppendScalar_MaxSize  15

/**
 *  Write the scaler in decimal format into buffer, and return a pointer to
 *  the next char after the last one written. Note: a terminating 0 is not
 *  written into buffer, which must be at least SkStrAppendScalar_MaxSize.
 *  Thus if the caller wants to add a 0 at the end, buffer must be at least
 *  SkStrAppendScalar_MaxSize + 1 bytes large.
 */
#define SkStrAppendScalar SkStrAppendFloat

char* SkStrAppendFloat(char buffer[], float);

/** \class SkString

    Light weight class for managing strings. Uses reference
    counting to make string assignments and copies very fast
    with no extra RAM cost. Assumes UTF8 encoding.
*/
class SK_API SkString {
public:
                SkString();
    explicit    SkString(size_t len);
    explicit    SkString(const char text[]);
                SkString(const char text[], size_t len);
                SkString(const SkString&);
                SkString(SkString&&);
                ~SkString();

    bool        isEmpty() const { return 0 == fRec->fLength; }
    size_t      size() const { return (size_t) fRec->fLength; }
    const char* c_str() const { return fRec->data(); }
    char operator[](size_t n) const { return this->c_str()[n]; }

    bool equals(const SkString&) const;
    bool equals(const char text[]) const;
    bool equals(const char text[], size_t len) const;

    bool startsWith(const char prefixStr[]) const {
        return SkStrStartsWith(fRec->data(), prefixStr);
    }
    bool startsWith(const char prefixChar) const {
        return SkStrStartsWith(fRec->data(), prefixChar);
    }
    bool endsWith(const char suffixStr[]) const {
        return SkStrEndsWith(fRec->data(), suffixStr);
    }
    bool endsWith(const char suffixChar) const {
        return SkStrEndsWith(fRec->data(), suffixChar);
    }
    bool contains(const char substring[]) const {
        return SkStrContains(fRec->data(), substring);
    }
    bool contains(const char subchar) const {
        return SkStrContains(fRec->data(), subchar);
    }
    int find(const char substring[]) const {
        return SkStrFind(fRec->data(), substring);
    }
    int findLastOf(const char subchar) const {
        return SkStrFindLastOf(fRec->data(), subchar);
    }

    friend bool operator==(const SkString& a, const SkString& b) {
        return a.equals(b);
    }
    friend bool operator!=(const SkString& a, const SkString& b) {
        return !a.equals(b);
    }

    // these methods edit the string

    SkString& operator=(const SkString&);
    SkString& operator=(SkString&&);
    SkString& operator=(const char text[]);

    char* writable_str();
    char& operator[](size_t n) { return this->writable_str()[n]; }

    void reset();
    /** Destructive resize, does not preserve contents. */
    void resize(size_t len) { this->set(nullptr, len); }
    void set(const SkString& src) { *this = src; }
    void set(const char text[]);
    void set(const char text[], size_t len);
    void setUTF16(const uint16_t[]);
    void setUTF16(const uint16_t[], size_t len);

    void insert(size_t offset, const SkString& src) { this->insert(offset, src.c_str(), src.size()); }
    void insert(size_t offset, const char text[]);
    void insert(size_t offset, const char text[], size_t len);
    void insertUnichar(size_t offset, SkUnichar);
    void insertS32(size_t offset, int32_t value);
    void insertS64(size_t offset, int64_t value, int minDigits = 0);
    void insertU32(size_t offset, uint32_t value);
    void insertU64(size_t offset, uint64_t value, int minDigits = 0);
    void insertHex(size_t offset, uint32_t value, int minDigits = 0);
    void insertScalar(size_t offset, SkScalar);

    void append(const SkString& str) { this->insert((size_t)-1, str); }
    void append(const char text[]) { this->insert((size_t)-1, text); }
    void append(const char text[], size_t len) { this->insert((size_t)-1, text, len); }
    void appendUnichar(SkUnichar uni) { this->insertUnichar((size_t)-1, uni); }
    void appendS32(int32_t value) { this->insertS32((size_t)-1, value); }
    void appendS64(int64_t value, int minDigits = 0) { this->insertS64((size_t)-1, value, minDigits); }
    void appendU32(uint32_t value) { this->insertU32((size_t)-1, value); }
    void appendU64(uint64_t value, int minDigits = 0) { this->insertU64((size_t)-1, value, minDigits); }
    void appendHex(uint32_t value, int minDigits = 0) { this->insertHex((size_t)-1, value, minDigits); }
    void appendScalar(SkScalar value) { this->insertScalar((size_t)-1, value); }

    void prepend(const SkString& str) { this->insert(0, str); }
    void prepend(const char text[]) { this->insert(0, text); }
    void prepend(const char text[], size_t len) { this->insert(0, text, len); }
    void prependUnichar(SkUnichar uni) { this->insertUnichar(0, uni); }
    void prependS32(int32_t value) { this->insertS32(0, value); }
    void prependS64(int32_t value, int minDigits = 0) { this->insertS64(0, value, minDigits); }
    void prependHex(uint32_t value, int minDigits = 0) { this->insertHex(0, value, minDigits); }
    void prependScalar(SkScalar value) { this->insertScalar((size_t)-1, value); }

    void printf(const char format[], ...) SK_PRINTF_LIKE(2, 3);
    void appendf(const char format[], ...) SK_PRINTF_LIKE(2, 3);
    void appendVAList(const char format[], va_list);
    void prependf(const char format[], ...) SK_PRINTF_LIKE(2, 3);
    void prependVAList(const char format[], va_list);

    void remove(size_t offset, size_t length);

    SkString& operator+=(const SkString& s) { this->append(s); return *this; }
    SkString& operator+=(const char text[]) { this->append(text); return *this; }
    SkString& operator+=(const char c) { this->append(&c, 1); return *this; }

    /**
     *  Swap contents between this and other. This function is guaranteed
     *  to never fail or throw.
     */
    void swap(SkString& other);

private:
    struct Rec {
    public:
        uint32_t    fLength; // logically size_t, but we want it to stay 32bits
        int32_t     fRefCnt;
        char        fBeginningOfData;

        char* data() { return &fBeginningOfData; }
        const char* data() const { return &fBeginningOfData; }
    };
    Rec* fRec;

#ifdef SK_DEBUG
    void validate() const;
#else
    void validate() const {}
#endif

    static const Rec gEmptyRec;
    static Rec* AllocRec(const char text[], size_t len);
    static Rec* RefRec(Rec*);
};

/// Creates a new string and writes into it using a printf()-style format.
SkString SkStringPrintf(const char* format, ...);

// Specialized to take advantage of SkString's fast swap path. The unspecialized function is
// declared in SkTypes.h and called by SkTSort.
template <> inline void SkTSwap(SkString& a, SkString& b) {
    a.swap(b);
}

enum SkStrSplitMode {
    // Strictly return all results. If the input is ",," and the separator is ',' this will return
    // an array of three empty strings.
    kStrict_SkStrSplitMode,

    // Only nonempty results will be added to the results. Multiple separators will be
    // coalesced. Separators at the beginning and end of the input will be ignored.  If the input is
    // ",," and the separator is ',', this will return an empty vector.
    kCoalesce_SkStrSplitMode
};

// Split str on any characters in delimiters into out.  (Think, strtok with a sane API.)
void SkStrSplit(const char* str, const char* delimiters, SkStrSplitMode splitMode,
                SkTArray<SkString>* out);
inline void SkStrSplit(const char* str, const char* delimiters, SkTArray<SkString>* out) {
    SkStrSplit(str, delimiters, kCoalesce_SkStrSplitMode, out);
}

#endif