blob: 795b47a0c4ea62bd85c31ac12fbd15589a1a18ab [file] [log] [blame]
* 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 SkUtils_DEFINED
#define SkUtils_DEFINED
#include "SkTypes.h"
#include "SkMath.h"
#include "SkOpts.h"
#include "SkTypeface.h"
/** Similar to memset(), but it assigns a 16, 32, or 64-bit value into the buffer.
@param buffer The memory to have value copied into it
@param value The value to be copied into buffer
@param count The number of times value should be copied into the buffer.
static inline void sk_memset16(uint16_t buffer[], uint16_t value, int count) {
SkOpts::memset16(buffer, value, count);
static inline void sk_memset32(uint32_t buffer[], uint32_t value, int count) {
SkOpts::memset32(buffer, value, count);
static inline void sk_memset64(uint64_t buffer[], uint64_t value, int count) {
SkOpts::memset64(buffer, value, count);
#define kMaxBytesInUTF8Sequence 4
#ifdef SK_DEBUG
int SkUTF8_LeadByteToCount(unsigned c);
#define SkUTF8_LeadByteToCount(c) ((((0xE5 << 24) >> ((unsigned)c >> 4 << 1)) & 3) + 1)
inline int SkUTF8_CountUTF8Bytes(const char utf8[]) {
return SkUTF8_LeadByteToCount(*(const uint8_t*)utf8);
int SkUTF8_CountUnichars(const char utf8[]);
/** These functions are safe: invalid sequences will return -1; */
int SkUTF8_CountUnichars(const void* utf8, size_t byteLength);
int SkUTF16_CountUnichars(const void* utf16, size_t byteLength);
int SkUTF32_CountUnichars(const void* utf32, size_t byteLength);
int SkUTFN_CountUnichars(SkTypeface::Encoding encoding, const void* utfN, size_t byteLength);
/** This function is safe: invalid UTF8 sequences will return -1
* When -1 is returned, ptr is unchanged.
* Precondition: *ptr < end;
SkUnichar SkUTF8_NextUnicharWithError(const char** ptr, const char* end);
/** this version replaces invalid utf-8 sequences with code point U+FFFD. */
inline SkUnichar SkUTF8_NextUnichar(const char** ptr, const char* end) {
SkUnichar val = SkUTF8_NextUnicharWithError(ptr, end);
if (val < 0) {
*ptr = end;
return val;
SkUnichar SkUTF8_ToUnichar(const char utf8[]);
SkUnichar SkUTF8_NextUnichar(const char**);
SkUnichar SkUTF8_PrevUnichar(const char**);
/** Return the number of bytes need to convert a unichar
into a utf8 sequence. Will be 1..kMaxBytesInUTF8Sequence,
or 0 if uni is illegal.
size_t SkUTF8_FromUnichar(SkUnichar uni, char utf8[] = nullptr);
#define SkUTF16_IsHighSurrogate(c) (((c) & 0xFC00) == 0xD800)
#define SkUTF16_IsLowSurrogate(c) (((c) & 0xFC00) == 0xDC00)
int SkUTF16_CountUnichars(const uint16_t utf16[]);
// returns the current unichar and then moves past it (*p++)
SkUnichar SkUTF16_NextUnichar(const uint16_t**);
SkUnichar SkUTF16_NextUnichar(const uint16_t** srcPtr, const uint16_t* end);
// this guy backs up to the previus unichar value, and returns it (*--p)
SkUnichar SkUTF16_PrevUnichar(const uint16_t**);
size_t SkUTF16_FromUnichar(SkUnichar uni, uint16_t utf16[] = nullptr);
size_t SkUTF16_ToUTF8(const uint16_t utf16[], int numberOf16BitValues,
char utf8[] = nullptr);
inline bool SkUnichar_IsVariationSelector(SkUnichar uni) {
/* The 'true' ranges are:
* 0x180B <= uni <= 0x180D
* 0xFE00 <= uni <= 0xFE0F
* 0xE0100 <= uni <= 0xE01EF
if (uni < 0x180B || uni > 0xE01EF) {
return false;
if ((uni > 0x180D && uni < 0xFE00) || (uni > 0xFE0F && uni < 0xE0100)) {
return false;
return true;
namespace SkHexadecimalDigits {
extern const char gUpper[16]; // 0-9A-F
extern const char gLower[16]; // 0-9a-f