skia2/include/core/SkString.h
reed@google.com 4bce115b31 make string's reference counting thread-safe
git-svn-id: http://skia.googlecode.com/svn/trunk@2268 2bbb7eff-a529-9590-31e7-b0007b416f81
2011-09-14 16:13:58 +00:00

197 lines
6.6 KiB
C++

/*
* 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 "SkScalar.h"
/* Some helper functions for C strings
*/
bool SkStrStartsWith(const char string[], const char prefix[]);
bool SkStrEndsWith(const char string[], const char suffix[]);
int SkStrStartsWithOneOf(const char string[], const char prefixes[]);
#define SkStrAppendS32_MaxSize 11
char* SkStrAppendS32(char buffer[], int32_t);
#define SkStrAppendS64_MaxSize 20
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.
*/
#ifdef SK_SCALAR_IS_FLOAT
#define SkStrAppendScalar SkStrAppendFloat
#else
#define SkStrAppendScalar SkStrAppendFixed
#endif
#ifdef SK_CAN_USE_FLOAT
char* SkStrAppendFloat(char buffer[], float);
#endif
char* SkStrAppendFixed(char buffer[], SkFixed);
/** \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 SkString {
public:
SkString();
explicit SkString(size_t len);
explicit SkString(const char text[]);
SkString(const char text[], size_t len);
SkString(const 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 prefix[]) const {
return SkStrStartsWith(fRec->data(), prefix);
}
bool endsWith(const char suffix[]) const {
return SkStrEndsWith(fRec->data(), suffix);
}
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=(const char text[]);
char* writable_str();
char& operator[](size_t n) { return this->writable_str()[n]; }
void reset();
void resize(size_t len) { this->set(NULL, 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 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 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[], ...);
void appendf(const char format[], ...);
void prependf(const char format[], ...);
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:
size_t fLength;
int32_t fRefCnt;
char fBeginningOfData;
char* data() { return &fBeginningOfData; }
const char* data() const { return &fBeginningOfData; }
};
Rec* fRec;
#ifdef SK_DEBUG
const char* fStr;
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*);
};
class SkAutoUCS2 {
public:
SkAutoUCS2(const char utf8[]);
~SkAutoUCS2();
/** This returns the number of ucs2 characters
*/
int count() const { return fCount; }
/** This returns a null terminated ucs2 string
*/
const uint16_t* getUCS2() const { return fUCS2; }
private:
int fCount;
uint16_t* fUCS2;
};
/// Creates a new string and writes into it using a printf()-style format.
SkString SkStringPrintf(const char* format, ...);
#endif