diff -r 000000000000 -r 6474c204b198 gfx/skia/trunk/src/core/SkUtils.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/gfx/skia/trunk/src/core/SkUtils.cpp Wed Dec 31 06:09:35 2014 +0100 @@ -0,0 +1,397 @@ + +/* + * 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. + */ + + +#include "SkUtils.h" + +#if 0 +#define assign_16_longs(dst, value) \ + do { \ + (dst)[0] = value; (dst)[1] = value; \ + (dst)[2] = value; (dst)[3] = value; \ + (dst)[4] = value; (dst)[5] = value; \ + (dst)[6] = value; (dst)[7] = value; \ + (dst)[8] = value; (dst)[9] = value; \ + (dst)[10] = value; (dst)[11] = value; \ + (dst)[12] = value; (dst)[13] = value; \ + (dst)[14] = value; (dst)[15] = value; \ + } while (0) +#else +#define assign_16_longs(dst, value) \ + do { \ + *(dst)++ = value; *(dst)++ = value; \ + *(dst)++ = value; *(dst)++ = value; \ + *(dst)++ = value; *(dst)++ = value; \ + *(dst)++ = value; *(dst)++ = value; \ + *(dst)++ = value; *(dst)++ = value; \ + *(dst)++ = value; *(dst)++ = value; \ + *(dst)++ = value; *(dst)++ = value; \ + *(dst)++ = value; *(dst)++ = value; \ + } while (0) +#endif + +/////////////////////////////////////////////////////////////////////////////// + +void sk_memset16_portable(uint16_t dst[], uint16_t value, int count) { + SkASSERT(dst != NULL && count >= 0); + + if (count <= 0) { + return; + } + + // not sure if this helps to short-circuit on small values of count + if (count < 8) { + do { + *dst++ = (uint16_t)value; + } while (--count != 0); + return; + } + + // ensure we're on a long boundary + if ((size_t)dst & 2) { + *dst++ = (uint16_t)value; + count -= 1; + } + + uint32_t value32 = ((uint32_t)value << 16) | value; + + // handle the bulk with our unrolled macro + { + int sixteenlongs = count >> 5; + if (sixteenlongs) { + uint32_t* dst32 = (uint32_t*)dst; + do { + assign_16_longs(dst32, value32); + } while (--sixteenlongs != 0); + dst = (uint16_t*)dst32; + count &= 31; + } + } + + // handle (most) of the rest + { + int longs = count >> 1; + if (longs) { + do { + *(uint32_t*)dst = value32; + dst += 2; + } while (--longs != 0); + } + } + + // cleanup a possible trailing short + if (count & 1) { + *dst = (uint16_t)value; + } +} + +void sk_memset32_portable(uint32_t dst[], uint32_t value, int count) { + SkASSERT(dst != NULL && count >= 0); + + int sixteenlongs = count >> 4; + if (sixteenlongs) { + do { + assign_16_longs(dst, value); + } while (--sixteenlongs != 0); + count &= 15; + } + + if (count) { + do { + *dst++ = value; + } while (--count != 0); + } +} + +static void sk_memset16_stub(uint16_t dst[], uint16_t value, int count) { + SkMemset16Proc proc = SkMemset16GetPlatformProc(); + sk_memset16 = proc ? proc : sk_memset16_portable; + sk_memset16(dst, value, count); +} + +SkMemset16Proc sk_memset16 = sk_memset16_stub; + +static void sk_memset32_stub(uint32_t dst[], uint32_t value, int count) { + SkMemset32Proc proc = SkMemset32GetPlatformProc(); + sk_memset32 = proc ? proc : sk_memset32_portable; + sk_memset32(dst, value, count); +} + +SkMemset32Proc sk_memset32 = sk_memset32_stub; + +/////////////////////////////////////////////////////////////////////////////// + +/* 0xxxxxxx 1 total + 10xxxxxx // never a leading byte + 110xxxxx 2 total + 1110xxxx 3 total + 11110xxx 4 total + + 11 10 01 01 xx xx xx xx 0... + 0xE5XX0000 + 0xE5 << 24 +*/ + +#ifdef SK_DEBUG + static void assert_utf8_leadingbyte(unsigned c) { + SkASSERT(c <= 0xF7); // otherwise leading byte is too big (more than 4 bytes) + SkASSERT((c & 0xC0) != 0x80); // can't begin with a middle char + } + + int SkUTF8_LeadByteToCount(unsigned c) { + assert_utf8_leadingbyte(c); + return (((0xE5 << 24) >> (c >> 4 << 1)) & 3) + 1; + } +#else + #define assert_utf8_leadingbyte(c) +#endif + +int SkUTF8_CountUnichars(const char utf8[]) { + SkASSERT(utf8); + + int count = 0; + + for (;;) { + int c = *(const uint8_t*)utf8; + if (c == 0) { + break; + } + utf8 += SkUTF8_LeadByteToCount(c); + count += 1; + } + return count; +} + +int SkUTF8_CountUnichars(const char utf8[], size_t byteLength) { + SkASSERT(NULL != utf8 || 0 == byteLength); + + int count = 0; + const char* stop = utf8 + byteLength; + + while (utf8 < stop) { + utf8 += SkUTF8_LeadByteToCount(*(const uint8_t*)utf8); + count += 1; + } + return count; +} + +SkUnichar SkUTF8_ToUnichar(const char utf8[]) { + SkASSERT(NULL != utf8); + + const uint8_t* p = (const uint8_t*)utf8; + int c = *p; + int hic = c << 24; + + assert_utf8_leadingbyte(c); + + if (hic < 0) { + uint32_t mask = (uint32_t)~0x3F; + hic <<= 1; + do { + c = (c << 6) | (*++p & 0x3F); + mask <<= 5; + } while ((hic <<= 1) < 0); + c &= ~mask; + } + return c; +} + +SkUnichar SkUTF8_NextUnichar(const char** ptr) { + SkASSERT(NULL != ptr && NULL != *ptr); + + const uint8_t* p = (const uint8_t*)*ptr; + int c = *p; + int hic = c << 24; + + assert_utf8_leadingbyte(c); + + if (hic < 0) { + uint32_t mask = (uint32_t)~0x3F; + hic <<= 1; + do { + c = (c << 6) | (*++p & 0x3F); + mask <<= 5; + } while ((hic <<= 1) < 0); + c &= ~mask; + } + *ptr = (char*)p + 1; + return c; +} + +SkUnichar SkUTF8_PrevUnichar(const char** ptr) { + SkASSERT(NULL != ptr && NULL != *ptr); + + const char* p = *ptr; + + if (*--p & 0x80) { + while (*--p & 0x40) { + ; + } + } + + *ptr = (char*)p; + return SkUTF8_NextUnichar(&p); +} + +size_t SkUTF8_FromUnichar(SkUnichar uni, char utf8[]) { + if ((uint32_t)uni > 0x10FFFF) { + SkDEBUGFAIL("bad unichar"); + return 0; + } + + if (uni <= 127) { + if (utf8) { + *utf8 = (char)uni; + } + return 1; + } + + char tmp[4]; + char* p = tmp; + size_t count = 1; + + SkDEBUGCODE(SkUnichar orig = uni;) + + while (uni > 0x7F >> count) { + *p++ = (char)(0x80 | (uni & 0x3F)); + uni >>= 6; + count += 1; + } + + if (utf8) { + p = tmp; + utf8 += count; + while (p < tmp + count - 1) { + *--utf8 = *p++; + } + *--utf8 = (char)(~(0xFF >> count) | uni); + } + + SkASSERT(utf8 == NULL || orig == SkUTF8_ToUnichar(utf8)); + return count; +} + +/////////////////////////////////////////////////////////////////////////////// + +int SkUTF16_CountUnichars(const uint16_t src[]) { + SkASSERT(src); + + int count = 0; + unsigned c; + while ((c = *src++) != 0) { + SkASSERT(!SkUTF16_IsLowSurrogate(c)); + if (SkUTF16_IsHighSurrogate(c)) { + c = *src++; + SkASSERT(SkUTF16_IsLowSurrogate(c)); + } + count += 1; + } + return count; +} + +int SkUTF16_CountUnichars(const uint16_t src[], int numberOf16BitValues) { + SkASSERT(src); + + const uint16_t* stop = src + numberOf16BitValues; + int count = 0; + while (src < stop) { + unsigned c = *src++; + SkASSERT(!SkUTF16_IsLowSurrogate(c)); + if (SkUTF16_IsHighSurrogate(c)) { + SkASSERT(src < stop); + c = *src++; + SkASSERT(SkUTF16_IsLowSurrogate(c)); + } + count += 1; + } + return count; +} + +SkUnichar SkUTF16_NextUnichar(const uint16_t** srcPtr) { + SkASSERT(srcPtr && *srcPtr); + + const uint16_t* src = *srcPtr; + SkUnichar c = *src++; + + SkASSERT(!SkUTF16_IsLowSurrogate(c)); + if (SkUTF16_IsHighSurrogate(c)) { + unsigned c2 = *src++; + SkASSERT(SkUTF16_IsLowSurrogate(c2)); + + // c = ((c & 0x3FF) << 10) + (c2 & 0x3FF) + 0x10000 + // c = (((c & 0x3FF) + 64) << 10) + (c2 & 0x3FF) + c = (c << 10) + c2 + (0x10000 - (0xD800 << 10) - 0xDC00); + } + *srcPtr = src; + return c; +} + +SkUnichar SkUTF16_PrevUnichar(const uint16_t** srcPtr) { + SkASSERT(srcPtr && *srcPtr); + + const uint16_t* src = *srcPtr; + SkUnichar c = *--src; + + SkASSERT(!SkUTF16_IsHighSurrogate(c)); + if (SkUTF16_IsLowSurrogate(c)) { + unsigned c2 = *--src; + SkASSERT(SkUTF16_IsHighSurrogate(c2)); + c = (c2 << 10) + c + (0x10000 - (0xD800 << 10) - 0xDC00); + } + *srcPtr = src; + return c; +} + +size_t SkUTF16_FromUnichar(SkUnichar uni, uint16_t dst[]) { + SkASSERT((unsigned)uni <= 0x10FFFF); + + int extra = (uni > 0xFFFF); + + if (dst) { + if (extra) { + // dst[0] = SkToU16(0xD800 | ((uni - 0x10000) >> 10)); + // dst[0] = SkToU16(0xD800 | ((uni >> 10) - 64)); + dst[0] = SkToU16((0xD800 - 64) + (uni >> 10)); + dst[1] = SkToU16(0xDC00 | (uni & 0x3FF)); + + SkASSERT(SkUTF16_IsHighSurrogate(dst[0])); + SkASSERT(SkUTF16_IsLowSurrogate(dst[1])); + } else { + dst[0] = SkToU16(uni); + SkASSERT(!SkUTF16_IsHighSurrogate(dst[0])); + SkASSERT(!SkUTF16_IsLowSurrogate(dst[0])); + } + } + return 1 + extra; +} + +size_t SkUTF16_ToUTF8(const uint16_t utf16[], int numberOf16BitValues, + char utf8[]) { + SkASSERT(numberOf16BitValues >= 0); + if (numberOf16BitValues <= 0) { + return 0; + } + + SkASSERT(utf16 != NULL); + + const uint16_t* stop = utf16 + numberOf16BitValues; + size_t size = 0; + + if (utf8 == NULL) { // just count + while (utf16 < stop) { + size += SkUTF8_FromUnichar(SkUTF16_NextUnichar(&utf16), NULL); + } + } else { + char* start = utf8; + while (utf16 < stop) { + utf8 += SkUTF8_FromUnichar(SkUTF16_NextUnichar(&utf16), utf8); + } + size = utf8 - start; + } + return size; +}