diff --git a/base64/base64.v b/base64/base64.v index 6c6152de44..db1fd66170 100644 --- a/base64/base64.v +++ b/base64/base64.v @@ -15,36 +15,53 @@ const ( ) pub fn decode(data string) string { - p := data.cstr() - len := data.len - mut pad := 0 - if len > 0 && (len % 4 != 0 || p[len - 1] == `=`) { - pad = 1 - } - L := ((len + 3) / 4 - pad) * 4 - str_len := L / 4 * 3 + pad - mut str := malloc(str_len + 2) - mut j := 0 - for i := 0; i < L; i = i+4 { - n := (Index[p[i]] << 18) | (Index[p[i + 1]] << 12) | - (Index[p[i + 2]] << 6) | (Index[p[i + 3]]) - str[j] = n >> 16 - j++ - str[j] = n >> 8 & 0xff - j++ - str[j] = n & 0xff - j++ - } - if pad > 0 { - mut nn := (Index[p[L]] << 18) | (Index[p[L + 1]] << 12) - str[str_len - 1] = nn >> 16 - if len > L + 2 && p[L + 2] != `=` { - nn = nn | (Index[p[L + 2]] << 6) - str[str_len] = nn >> 8 & 0xff + mut padding := 0 + if data.ends_with('=') { + if data.ends_with('==') { + padding = 2 + } else { + padding = 1 } } - str[str_len + 1] = `\0` - return tos(str, str_len+1) + //input_length is the length of meaningful data + input_length := data.len - padding + output_length := input_length * 3 / 4 + + mut i := 0 + mut j := 0 + mut str := malloc(output_length) + + for i < input_length { + mut char_a := 0 + mut char_b := 0 + mut char_c := 0 + mut char_d := 0 + + if i < input_length { + char_a = Index[int(data[i])] + i++ + } + if i < input_length { + char_b = Index[int(data[i])] + i++ + } + if i < input_length { + char_c = Index[int(data[i])] + i++ + } + if i < input_length { + char_d = Index[int(data[i])] + i++ + } + + decoded_bytes := (char_a << 18) | (char_b << 12) | (char_c << 6) | (char_d << 0) + str[j] = decoded_bytes >> 16 + str[j+1] = (decoded_bytes >> 8) & 0xff + str[j+2] = (decoded_bytes >> 0) & 0xff + + j += 3 + } + return tos(str, output_length) } const ( diff --git a/base64/base64_test.v b/base64/base64_test.v index 67f985b099..55f3dc80c6 100644 --- a/base64/base64_test.v +++ b/base64/base64_test.v @@ -3,5 +3,14 @@ import base64 fn test_decode() { assert base64.decode('TWFuIGlzIGRpc3Rpbmd1aXNoZWQsIG5vdCBvbmx5IGJ5IGhpcyByZWFzb24sIGJ1dCBieSB0aGlzIHNpbmd1bGFyIHBhc3Npb24gZnJvbSBvdGhlciBhbmltYWxzLCB3aGljaCBpcyBhIGx1c3Qgb2YgdGhlIG1pbmQsIHRoYXQgYnkgYSBwZXJzZXZlcmFuY2Ugb2YgZGVsaWdodCBpbiB0aGUgY29udGludWVkIGFuZCBpbmRlZmF0aWdhYmxlIGdlbmVyYXRpb24gb2Yga25vd2xlZGdlLCBleGNlZWRzIHRoZSBzaG9ydCB2ZWhlbWVuY2Ugb2YgYW55IGNhcm5hbCBwbGVhc3VyZS4=') == 'Man is distinguished, not only by his reason, but by this singular passion from other animals, which is a lust of the mind, that by a perseverance of delight in the continued and indefatigable generation of knowledge, exceeds the short vehemence of any carnal pleasure.' + + // Test for incorrect padding. + assert base64.decode('aGk') == 'hi' + assert base64.decode('aGk=') == 'hi' + assert base64.decode('aGk==') == 'hi' } +fn test_encode() { + assert base64.encode('Man is distinguished, not only by his reason, but by this singular passion from other animals, which is a lust of the mind, that by a perseverance of delight in the continued and indefatigable generation of knowledge, exceeds the short vehemence of any carnal pleasure.') + == 'TWFuIGlzIGRpc3Rpbmd1aXNoZWQsIG5vdCBvbmx5IGJ5IGhpcyByZWFzb24sIGJ1dCBieSB0aGlzIHNpbmd1bGFyIHBhc3Npb24gZnJvbSBvdGhlciBhbmltYWxzLCB3aGljaCBpcyBhIGx1c3Qgb2YgdGhlIG1pbmQsIHRoYXQgYnkgYSBwZXJzZXZlcmFuY2Ugb2YgZGVsaWdodCBpbiB0aGUgY29udGludWVkIGFuZCBpbmRlZmF0aWdhYmxlIGdlbmVyYXRpb24gb2Yga25vd2xlZGdlLCBleGNlZWRzIHRoZSBzaG9ydCB2ZWhlbWVuY2Ugb2YgYW55IGNhcm5hbCBwbGVhc3VyZS4=' +}