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Diffstat (limited to 'Source/kwsys/Base64.c')
| -rw-r--r-- | Source/kwsys/Base64.c | 262 |
1 files changed, 262 insertions, 0 deletions
diff --git a/Source/kwsys/Base64.c b/Source/kwsys/Base64.c new file mode 100644 index 0000000..cdb0675 --- /dev/null +++ b/Source/kwsys/Base64.c @@ -0,0 +1,262 @@ +/*========================================================================= + +Program: KWSys - Kitware System Library +Module: $RCSfile$ +Language: C++ +Date: $Date$ +Version: $Revision$ + +Copyright (c) 2002 Kitware, Inc., Insight Consortium. All rights reserved. +See http://www.cmake.org/HTML/Copyright.html for details. + +This software is distributed WITHOUT ANY WARRANTY; without even +the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR +PURPOSE. See the above copyright notices for more information. + +=========================================================================*/ +#define KWSYS_IN_PROCESS_C +#include <Base64.h> + +/*--------------------------------------------------------------------------*/ +static const unsigned char kwsysBase64EncodeTable[65] = +"ABCDEFGHIJKLMNOPQRSTUVWXYZ" +"abcdefghijklmnopqrstuvwxyz" +"0123456789+/"; + +/*--------------------------------------------------------------------------*/ +static const unsigned char kwsysBase64DecodeTable[256] = +{ + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0xFF,0xFF,0x3E,0xFF,0xFF,0xFF,0x3F, + 0x34,0x35,0x36,0x37,0x38,0x39,0x3A,0x3B, + 0x3C,0x3D,0xFF,0xFF,0xFF,0x00,0xFF,0xFF, + 0xFF,0x00,0x01,0x02,0x03,0x04,0x05,0x06, + 0x07,0x08,0x09,0x0A,0x0B,0x0C,0x0D,0x0E, + 0x0F,0x10,0x11,0x12,0x13,0x14,0x15,0x16, + 0x17,0x18,0x19,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0x1A,0x1B,0x1C,0x1D,0x1E,0x1F,0x20, + 0x21,0x22,0x23,0x24,0x25,0x26,0x27,0x28, + 0x29,0x2A,0x2B,0x2C,0x2D,0x2E,0x2F,0x30, + 0x31,0x32,0x33,0xFF,0xFF,0xFF,0xFF,0xFF, + /*------------------------------------*/ + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, + 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF +}; + +/*--------------------------------------------------------------------------*/ +static unsigned char kwsysBase64EncodeChar(unsigned char c) +{ + return kwsysBase64EncodeTable[c]; +} + +/*--------------------------------------------------------------------------*/ +static unsigned char kwsysBase64DecodeChar(unsigned char c) +{ + return kwsysBase64DecodeTable[c]; +} + +/*--------------------------------------------------------------------------*/ +/* Encode 3 bytes into a 4 byte string. */ +void kwsysBase64_Encode3(const unsigned char *src, unsigned char *dest) +{ + dest[0] = kwsysBase64EncodeChar((src[0] >> 2) & 0x3F); + dest[1] = kwsysBase64EncodeChar(((src[0] << 4) & 0x30)|((src[1] >> 4) & 0x0F)); + dest[2] = kwsysBase64EncodeChar(((src[1] << 2) & 0x3C)|((src[2] >> 6) & 0x03)); + dest[3] = kwsysBase64EncodeChar(src[2] & 0x3F); +} + +/*--------------------------------------------------------------------------*/ +/* Encode 2 bytes into a 4 byte string. */ +void kwsysBase64_Encode2(const unsigned char *src, unsigned char *dest) +{ + dest[0] = kwsysBase64EncodeChar((src[0] >> 2) & 0x3F); + dest[1] = kwsysBase64EncodeChar(((src[0] << 4) & 0x30)|((src[1] >> 4) & 0x0F)); + dest[2] = kwsysBase64EncodeChar(((src[1] << 2) & 0x3C)|((src[2] >> 6) & 0x03)); + dest[3] = '='; +} + +/*--------------------------------------------------------------------------*/ +/* Encode 1 bytes into a 4 byte string. */ +void kwsysBase64_Encode1(const unsigned char *src, unsigned char *dest) +{ + dest[0] = kwsysBase64EncodeChar((src[0] >> 2) & 0x3F); + dest[1] = kwsysBase64EncodeChar(((src[0] << 4) & 0x30)); + dest[2] = '='; + dest[3] = '='; +} + +/*--------------------------------------------------------------------------*/ +/* Encode 'length' bytes from the input buffer and store the + encoded stream into the output buffer. Return the length of the encoded + buffer (output). Note that the output buffer must be allocated by the caller + (length * 1.5 should be a safe estimate). If 'mark_end' is true than an + extra set of 4 bytes is added to the end of the stream if the input is a + multiple of 3 bytes. These bytes are invalid chars and therefore they will + stop the decoder thus enabling the caller to decode a stream without + actually knowing how much data to expect (if the input is not a multiple of + 3 bytes then the extra padding needed to complete the encode 4 bytes will + stop the decoding anyway). */ +unsigned long kwsysBase64_Encode(const unsigned char *input, + unsigned long length, unsigned char *output, int mark_end) +{ + const unsigned char *ptr = input; + const unsigned char *end = input + length; + unsigned char *optr = output; + + /* Encode complete triplet */ + + while ((end - ptr) >= 3) + { + kwsysBase64_Encode3(ptr, optr); + ptr += 3; + optr += 4; + } + + /* Encodes a 2-byte ending into 3 bytes and 1 pad byte and writes. */ + + if (end - ptr == 2) + { + kwsysBase64_Encode2(ptr, optr); + optr += 4; + } + + /* Encodes a 1-byte ending into 2 bytes and 2 pad bytes */ + + else if (end - ptr == 1) + { + kwsysBase64_Encode1(ptr, optr); + optr += 4; + } + + /* Do we need to mark the end */ + + else if (mark_end) + { + optr[0] = optr[1] = optr[2] = optr[3] = '='; + optr += 4; + } + + return optr - output; +} +/*--------------------------------------------------------------------------*/ +/* Decode 4 bytes into a 3 byte string. */ +int kwsysBase64_Decode3(const unsigned char *src, unsigned char *dest) +{ + unsigned char d0, d1, d2, d3; + + d0 = kwsysBase64DecodeChar(src[0]); + d1 = kwsysBase64DecodeChar(src[1]); + d2 = kwsysBase64DecodeChar(src[2]); + d3 = kwsysBase64DecodeChar(src[3]); + + /* Make sure all characters were valid */ + + if (d0 == 0xFF || d1 == 0xFF || d2 == 0xFF || d3 == 0xFF) + { + return 0; + } + + /* Decode the 3 bytes */ + + dest[0] = ((d0 << 2) & 0xFC) | ((d1 >> 4) & 0x03); + dest[1] = ((d1 << 4) & 0xF0) | ((d2 >> 2) & 0x0F); + dest[2] = ((d2 << 6) & 0xC0) | ((d3 >> 0) & 0x3F); + + /* Return the number of bytes actually decoded */ + + if (src[2] == '=') + { + return 1; + } + if (src[3] == '=') + { + return 2; + } + return 3; +} + +/*--------------------------------------------------------------------------*/ +/* Decode bytes from the input buffer and store the decoded stream + into the output buffer until 'length' bytes have been decoded. Return the + real length of the decoded stream (which should be equal to 'length'). Note + that the output buffer must be allocated by the caller. If + 'max_input_length' is not null, then it specifies the number of encoded + bytes that should be at most read from the input buffer. In that case the + 'length' parameter is ignored. This enables the caller to decode a stream + without actually knowing how much decoded data to expect (of course, the + buffer must be large enough). */ +unsigned long kwsysBase64_Decode(const unsigned char *input, + unsigned long length, unsigned char *output, unsigned long max_input_length) +{ + const unsigned char *ptr = input; + unsigned char *optr = output; + + /* Decode complete triplet */ + + if (max_input_length) + { + const unsigned char *end = input + max_input_length; + while (ptr < end) + { + int len = kwsysBase64_Decode3(ptr, optr); + optr += len; + if(len < 3) + { + return optr - output; + } + ptr += 4; + } + } + else + { + unsigned char *oend = output + length; + while ((oend - optr) >= 3) + { + int len = kwsysBase64_Decode3(ptr, optr); + optr += len; + if(len < 3) + { + return optr - output; + } + ptr += 4; + } + + /* Decode the last triplet */ + + if (oend - optr == 2) + { + unsigned char temp[3]; + int len = kwsysBase64_Decode3(ptr, temp); + optr[0] = temp[0]; + optr[1] = temp[1]; + optr += (len > 2 ? 2 : len); + } + else if (oend - optr == 1) + { + unsigned char temp[3]; + int len = kwsysBase64_Decode3(ptr, temp); + optr[0] = temp[0]; + optr += (len > 2 ? 2 : len); + } + } + + return optr - output; +} |