1 /*
2 * Copyright 2006 The Android Open Source Project
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8 #ifndef SkUtils_DEFINED
9 #define SkUtils_DEFINED
10
11 #include "SkTypes.h"
12 #include "SkMath.h"
13 #include "SkOpts.h"
14
15 /** Similar to memset(), but it assigns a 16, 32, or 64-bit value into the buffer.
16 @param buffer The memory to have value copied into it
17 @param value The value to be copied into buffer
18 @param count The number of times value should be copied into the buffer.
19 */
sk_memset16(uint16_t buffer[],uint16_t value,int count)20 static inline void sk_memset16(uint16_t buffer[], uint16_t value, int count) {
21 SkOpts::memset16(buffer, value, count);
22 }
sk_memset32(uint32_t buffer[],uint32_t value,int count)23 static inline void sk_memset32(uint32_t buffer[], uint32_t value, int count) {
24 SkOpts::memset32(buffer, value, count);
25 }
sk_memset64(uint64_t buffer[],uint64_t value,int count)26 static inline void sk_memset64(uint64_t buffer[], uint64_t value, int count) {
27 SkOpts::memset64(buffer, value, count);
28 }
29 ///////////////////////////////////////////////////////////////////////////////
30
31 #define kMaxBytesInUTF8Sequence 4
32
33 #ifdef SK_DEBUG
34 int SkUTF8_LeadByteToCount(unsigned c);
35 #else
36 #define SkUTF8_LeadByteToCount(c) ((((0xE5 << 24) >> ((unsigned)c >> 4 << 1)) & 3) + 1)
37 #endif
38
SkUTF8_CountUTF8Bytes(const char utf8[])39 inline int SkUTF8_CountUTF8Bytes(const char utf8[]) {
40 SkASSERT(utf8);
41 return SkUTF8_LeadByteToCount(*(const uint8_t*)utf8);
42 }
43
44 int SkUTF8_CountUnichars(const char utf8[]);
45
46 /** These functions are safe: invalid sequences will return -1; */
47 int SkUTF8_CountUnichars(const void* utf8, size_t byteLength);
48 int SkUTF16_CountUnichars(const void* utf16, size_t byteLength);
49 int SkUTF32_CountUnichars(const void* utf32, size_t byteLength);
50
51 /** This function is safe: invalid UTF8 sequences will return -1
52 * When -1 is returned, ptr is unchanged.
53 * Precondition: *ptr < end;
54 */
55 SkUnichar SkUTF8_NextUnicharWithError(const char** ptr, const char* end);
56
57 /** this version replaces invalid utf-8 sequences with code point U+FFFD. */
SkUTF8_NextUnichar(const char ** ptr,const char * end)58 inline SkUnichar SkUTF8_NextUnichar(const char** ptr, const char* end) {
59 SkUnichar val = SkUTF8_NextUnicharWithError(ptr, end);
60 if (val < 0) {
61 *ptr = end;
62 return 0xFFFD; // REPLACEMENT CHARACTER
63 }
64 return val;
65 }
66
67 SkUnichar SkUTF8_ToUnichar(const char utf8[]);
68 SkUnichar SkUTF8_NextUnichar(const char**);
69 SkUnichar SkUTF8_PrevUnichar(const char**);
70
71 /** Return the number of bytes need to convert a unichar
72 into a utf8 sequence. Will be 1..kMaxBytesInUTF8Sequence,
73 or 0 if uni is illegal.
74 */
75 size_t SkUTF8_FromUnichar(SkUnichar uni, char utf8[] = nullptr);
76
77 ///////////////////////////////////////////////////////////////////////////////
78
79 #define SkUTF16_IsHighSurrogate(c) (((c) & 0xFC00) == 0xD800)
80 #define SkUTF16_IsLowSurrogate(c) (((c) & 0xFC00) == 0xDC00)
81
82 int SkUTF16_CountUnichars(const uint16_t utf16[]);
83 // returns the current unichar and then moves past it (*p++)
84 SkUnichar SkUTF16_NextUnichar(const uint16_t**);
85 // this guy backs up to the previus unichar value, and returns it (*--p)
86 SkUnichar SkUTF16_PrevUnichar(const uint16_t**);
87 size_t SkUTF16_FromUnichar(SkUnichar uni, uint16_t utf16[] = nullptr);
88
89 size_t SkUTF16_ToUTF8(const uint16_t utf16[], int numberOf16BitValues,
90 char utf8[] = nullptr);
91
SkUnichar_IsVariationSelector(SkUnichar uni)92 inline bool SkUnichar_IsVariationSelector(SkUnichar uni) {
93 /* The 'true' ranges are:
94 * 0x180B <= uni <= 0x180D
95 * 0xFE00 <= uni <= 0xFE0F
96 * 0xE0100 <= uni <= 0xE01EF
97 */
98 if (uni < 0x180B || uni > 0xE01EF) {
99 return false;
100 }
101 if ((uni > 0x180D && uni < 0xFE00) || (uni > 0xFE0F && uni < 0xE0100)) {
102 return false;
103 }
104 return true;
105 }
106
107 namespace SkHexadecimalDigits {
108 extern const char gUpper[16]; // 0-9A-F
109 extern const char gLower[16]; // 0-9a-f
110 }
111
112 #endif
113