diff --git a/cmText.c b/cmText.c index 7af0957..1dba9ec 100644 --- a/cmText.c +++ b/cmText.c @@ -1026,3 +1026,212 @@ cmChar_t* cmTextOutdent( cmChar_t* s, unsigned outdent ) return s; } + +unsigned cmTextDecodeBase64BufferByteCount( const char* xV, unsigned xN ) +{ + if( xN % 4 != 0 ) + return cmInvalidCnt; + + unsigned yN = xN / 4 * 3; + + if( xV[xN-1] == '=' ) + yN -= 1; + + if( xV[xN-2] == '=' ) + yN -= 2; + + return yN; +} + +cmTxRC_t cmTextDecodeBase64( const char* xV, unsigned xN, void* yV, unsigned yN ) +{ + int t[] = + { + 64, // 0 + 64, // 1 + 64, // 2 + 64, // 3 + 64, // 4 + 64, // 5 + 64, // 6 + 64, // 7 + 64, // 8 + 64, // 9 + 64, // 10 + 64, // 11 + 64, // 12 + 64, // 13 + 64, // 14 + 64, // 15 + 64, // 16 + 64, // 17 + 64, // 18 + 64, // 19 + 64, // 20 + 64, // 21 + 64, // 22 + 64, // 23 + 64, // 24 + 64, // 25 + 64, // 26 + 64, // 27 + 64, // 28 + 64, // 29 + 64, // 30 + 64, // 31 + 64, // 32 + 64, // 33 + 64, // 34 + 64, // 35 + 64, // 36 + 64, // 37 + 64, // 38 + 64, // 39 + 64, // 40 + 64, // 41 + 64, // 42 + 62, // 43 + + 64, // 44 + 64, // 45 + 64, // 46 + 63, // 47 / + 52, // 48 0 + 53, // 49 1 + 54, // 50 2 + 55, // 51 3 + 56, // 52 4 + 57, // 53 5 + 58, // 54 6 + 59, // 55 7 + 60, // 56 8 + 61, // 57 9 + 64, // 58 + 64, // 59 + 64, // 60 + 64, // 61 + 64, // 62 + 64, // 63 + 64, // 64 + 0, // 65 A + 1, // 66 B + 2, // 67 C + 3, // 68 D + 4, // 69 E + 5, // 70 F + 6, // 71 G + 7, // 72 H + 8, // 73 I + 9, // 74 J + 10, // 75 K + 11, // 76 L + 12, // 77 M + 13, // 78 N + 14, // 79 O + 15, // 80 P + 16, // 81 Q + 17, // 82 R + 18, // 83 S + 19, // 84 T + 20, // 85 U + 21, // 86 V + 22, // 87 W + 23, // 88 X + 24, // 89 Y + 25, // 90 Z + 64, // 91 + 64, // 92 + 64, // 93 + 64, // 94 + 64, // 95 + 64, // 96 + 26, // 97 a + 27, // 98 b + 28, // 99 c + 29, //100 d + 30, //101 e + 31, //102 f + 32, //103 g + 33, //104 h + 34, //105 i + 35, //106 j + 36, //107 k + 37, //108 l + 38, //109 m + 39, //110 n + 40, //111 o + 41, //112 p + 42, //113 q + 43, //114 r + 44, //115 s + 45, //116 t + 46, //117 u + 47, //118 v + 48, //119 w + 49, //120 x + 50, //121 y + 51, //122 z + 64, //123 + 64, //124 + 64, //125 + 64, //126 + 64 //127 + }; + + unsigned i = 0; + unsigned j = 0; + char* zV = (char*)yV; + + while( i < xN ) + { + unsigned yn = 3; + + if( xV[i+3] == '=' ) + --yn; + + if( xV[i+2] == '=' ) + --yn; + + unsigned v = 0; + + v += t[(int)xV[i++]] << 18; + v += t[(int)xV[i++]] << 12; + v += t[(int)xV[i++]] << 6; + v += t[(int)xV[i++]] << 0; + + if( j >= yN ) + break; + + zV[j++] = (v & 0xff0000) >> 16; + + if( yn > 1 ) + { + if( j >= yN ) + break; + + zV[j++] = (v & 0x00ff00) >> 8; + } + + if( yn > 2 ) + { + if( j >= yN ) + break; + + zV[j++] = (v & 0x0000ff) >> 0; + } + + } + + return j; +} + + +unsigned cmTextEncodeBase64BufferByteCount( unsigned binByteCnt ) +{ + return 0; +} + +cmTxRC_t cmTextEncodeBase64( const void* xV, unsigned xN, char* yV, unsigned yN ) +{ + // const char* t = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; + return kOkTxRC; +} diff --git a/cmText.h b/cmText.h index 8742abe..dfc10f6 100644 --- a/cmText.h +++ b/cmText.h @@ -18,7 +18,8 @@ extern "C" { kOkTxRC = 0, kNullTxRC, kCvtErrTxRC, - kLHeapFailTxRC + kLHeapFailTxRC, + kBufTooSmallTxRC }; typedef unsigned cmTxRC_t; @@ -273,6 +274,28 @@ extern "C" { // then all leading white space is removed. cmChar_t* cmTextOutdent( cmChar_t* s, unsigned n ); + // Given a string containing binary data encoded as base64 + // return the size of the buffer required to hold the + // decoded binary data. Note that if xV[] is a legal base64 + // string then xN must be a multiple of 4. If xN is not + // a mulitple of 4 then the function returns kInvalidCnt. + unsigned cmTextDecodeBase64BufferByteCount( const char* xV, unsigned xN ); + + // Decode the base64 data in xV[xN] into yV[yN]. Note that the + // minimum value of yN can be determined via + // cmTextDecodeBase64BufferByteCount(). + // Return the actual count of bytes decoded into yV[]. + unsigned cmTextDecodeBase64( const char* xV, unsigned xN, void* yV, unsigned yN ); + + // Given the count of bytes in a binary array, return + // the count of bytes required to store the array in base64. + unsigned cmTextEncodeBase64BufferByteCount( unsigned xN ); + + // Encode the binary array xV[xN] into yV[yN]. Note that the value + // of yN can be determined via cmTextEncodeBase64BufferByteCount(). + cmTxRC_t cmTextEncodeBase64( const void* xV, unsigned xN, char* yV, unsigned yN ); + + //) //}