diff options
Diffstat (limited to 'gfx/skia/skia/src/utils/SkBase64.cpp')
| -rw-r--r-- | gfx/skia/skia/src/utils/SkBase64.cpp | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/gfx/skia/skia/src/utils/SkBase64.cpp b/gfx/skia/skia/src/utils/SkBase64.cpp new file mode 100644 index 0000000000..4ebb9d7ae2 --- /dev/null +++ b/gfx/skia/skia/src/utils/SkBase64.cpp @@ -0,0 +1,154 @@ +/* + * 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 "include/utils/SkBase64.h" + +#include <cstdint> + +#define DecodePad -2 +#define EncodePad 64 + +static const char default_encode[] = + "ABCDEFGHIJKLMNOPQRSTUVWXYZ" + "abcdefghijklmnopqrstuvwxyz" + "0123456789+/="; + +static const signed char decodeData[] = { + 62, -1, -1, -1, 63, + 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, DecodePad, -1, -1, + -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, + 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, + -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, + 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51 +}; + +#if defined _WIN32 // disable 'two', etc. may be used without having been initialized +#pragma warning ( push ) +#pragma warning ( disable : 4701 ) +#endif + +SkBase64::Error SkBase64::Decode(const void* srcv, size_t srcLength, void* dstv, size_t* dstLength){ + const unsigned char* src = static_cast<const unsigned char*>(srcv); + unsigned char* dst = static_cast<unsigned char*>(dstv); + + int i = 0; + bool padTwo = false; + bool padThree = false; + char unsigned const * const end = src + srcLength; + while (src < end) { + unsigned char bytes[4]; + int byte = 0; + do { + unsigned char srcByte = *src++; + if (srcByte == 0) + goto goHome; + if (srcByte <= ' ') + continue; // treat as white space + if (srcByte < '+' || srcByte > 'z') + return kBadCharError; + signed char decoded = decodeData[srcByte - '+']; + bytes[byte] = decoded; + if (decoded < 0) { + if (decoded == DecodePad) + goto handlePad; + return kBadCharError; + } else + byte++; + if (*src) + continue; + if (byte == 0) + goto goHome; + if (byte == 4) + break; +handlePad: + if (byte < 2) + return kPadError; + padThree = true; + if (byte == 2) + padTwo = true; + break; + } while (byte < 4); + int two = 0; + int three = 0; + if (dst) { + int one = (uint8_t) (bytes[0] << 2); + two = bytes[1]; + one |= two >> 4; + two = (uint8_t) ((two << 4) & 0xFF); + three = bytes[2]; + two |= three >> 2; + three = (uint8_t) ((three << 6) & 0xFF); + three |= bytes[3]; + SkASSERT(one < 256 && two < 256 && three < 256); + dst[i] = (unsigned char) one; + } + i++; + if (padTwo) + break; + if (dst) + dst[i] = (unsigned char) two; + i++; + if (padThree) + break; + if (dst) + dst[i] = (unsigned char) three; + i++; + } +goHome: + *dstLength = i; + return kNoError; +} + +#if defined _WIN32 +#pragma warning ( pop ) +#endif + +size_t SkBase64::Encode(const void* srcv, size_t length, void* dstv, const char* encodeMap) { + const unsigned char* src = static_cast<const unsigned char*>(srcv); + unsigned char* dst = static_cast<unsigned char*>(dstv); + + const char* encode; + if (nullptr == encodeMap) { + encode = default_encode; + } else { + encode = encodeMap; + } + if (dst) { + size_t remainder = length % 3; + char unsigned const * const end = &src[length - remainder]; + while (src < end) { + unsigned a = *src++; + unsigned b = *src++; + unsigned c = *src++; + int d = c & 0x3F; + c = (c >> 6 | b << 2) & 0x3F; + b = (b >> 4 | a << 4) & 0x3F; + a = a >> 2; + *dst++ = encode[a]; + *dst++ = encode[b]; + *dst++ = encode[c]; + *dst++ = encode[d]; + } + if (remainder > 0) { + int k1 = 0; + int k2 = EncodePad; + int a = (uint8_t) *src++; + if (remainder == 2) + { + int b = *src++; + k1 = b >> 4; + k2 = (b << 2) & 0x3F; + } + *dst++ = encode[a >> 2]; + *dst++ = encode[(k1 | a << 4) & 0x3F]; + *dst++ = encode[k2]; + *dst++ = encode[EncodePad]; + } + } + return (length + 2) / 3 * 4; +} |