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 /** This function is safe: invalid UTF8 sequences will return -1; */
47 int SkUTF8_CountUnicharsWithError(const char utf8[], size_t byteLength);
48
49 /** This function is safe: invalid UTF8 sequences will return 0; */
SkUTF8_CountUnichars(const char utf8[],size_t byteLength)50 inline int SkUTF8_CountUnichars(const char utf8[], size_t byteLength) {
51 return SkClampPos(SkUTF8_CountUnicharsWithError(utf8, byteLength));
52 }
53
54 /** This function is safe: invalid UTF8 sequences will return -1
55 * When -1 is returned, ptr is unchanged.
56 * Precondition: *ptr < end;
57 */
58 SkUnichar SkUTF8_NextUnicharWithError(const char** ptr, const char* end);
59
60 /** this version replaces invalid utf-8 sequences with code point U+FFFD. */
SkUTF8_NextUnichar(const char ** ptr,const char * end)61 inline SkUnichar SkUTF8_NextUnichar(const char** ptr, const char* end) {
62 SkUnichar val = SkUTF8_NextUnicharWithError(ptr, end);
63 if (val < 0) {
64 *ptr = end;
65 return 0xFFFD; // REPLACEMENT CHARACTER
66 }
67 return val;
68 }
69
70 SkUnichar SkUTF8_ToUnichar(const char utf8[]);
71 SkUnichar SkUTF8_NextUnichar(const char**);
72 SkUnichar SkUTF8_PrevUnichar(const char**);
73
74 /** Return the number of bytes need to convert a unichar
75 into a utf8 sequence. Will be 1..kMaxBytesInUTF8Sequence,
76 or 0 if uni is illegal.
77 */
78 size_t SkUTF8_FromUnichar(SkUnichar uni, char utf8[] = NULL);
79
80 ///////////////////////////////////////////////////////////////////////////////
81
82 #define SkUTF16_IsHighSurrogate(c) (((c) & 0xFC00) == 0xD800)
83 #define SkUTF16_IsLowSurrogate(c) (((c) & 0xFC00) == 0xDC00)
84
85 int SkUTF16_CountUnichars(const uint16_t utf16[]);
86 int SkUTF16_CountUnichars(const uint16_t utf16[], int numberOf16BitValues);
87 // returns the current unichar and then moves past it (*p++)
88 SkUnichar SkUTF16_NextUnichar(const uint16_t**);
89 // this guy backs up to the previus unichar value, and returns it (*--p)
90 SkUnichar SkUTF16_PrevUnichar(const uint16_t**);
91 size_t SkUTF16_FromUnichar(SkUnichar uni, uint16_t utf16[] = NULL);
92
93 size_t SkUTF16_ToUTF8(const uint16_t utf16[], int numberOf16BitValues,
94 char utf8[] = NULL);
95
SkUnichar_IsVariationSelector(SkUnichar uni)96 inline bool SkUnichar_IsVariationSelector(SkUnichar uni) {
97 /* The 'true' ranges are:
98 * 0x180B <= uni <= 0x180D
99 * 0xFE00 <= uni <= 0xFE0F
100 * 0xE0100 <= uni <= 0xE01EF
101 */
102 if (uni < 0x180B || uni > 0xE01EF) {
103 return false;
104 }
105 if ((uni > 0x180D && uni < 0xFE00) || (uni > 0xFE0F && uni < 0xE0100)) {
106 return false;
107 }
108 return true;
109 }
110
111 namespace SkHexadecimalDigits {
112 extern const char gUpper[16]; // 0-9A-F
113 extern const char gLower[16]; // 0-9a-f
114 }
115
116 #endif
117