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Base32 encoding and decoding functions in Microsoft T-SQL
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IF EXISTS ( | |
SELECT * | |
FROM sys.objects | |
WHERE object_id = OBJECT_ID(N'[dbo].[base32enc]') | |
AND type IN ( | |
N'FN' | |
,N'IF' | |
,N'TF' | |
,N'FS' | |
,N'FT' | |
) | |
) | |
DROP FUNCTION [dbo].[base32enc] | |
GO | |
CREATE FUNCTION [dbo].[base32enc] ( | |
@x VARBINARY(max) | |
,@pad INT = 1 | |
) | |
RETURNS VARCHAR(max) | |
AS | |
BEGIN | |
/* RFC 4648 compliant BASE32 encoding function, takes varbinary data to | |
encode as first parameter, and then a 0 or 1 to indicate whether or not | |
padding characters (equals signs) should be included in the output. */ | |
DECLARE @p INT | |
DECLARE @c BIGINT | |
DECLARE @s BIGINT | |
DECLARE @q BIGINT | |
DECLARE @t BIGINT | |
DECLARE @o VARCHAR(max) | |
DECLARE @op VARCHAR(8) | |
SET @o = '' | |
SET @p = DATALENGTH(@x) % 5 --encode with 40-bit blocks | |
IF @p <> 0 | |
SET @x = @x + SUBSTRING(0x0000000000, 1, 5 - @p) | |
SET @c = 0 | |
WHILE @c < DATALENGTH(@x) | |
BEGIN | |
SET @s = 0 | |
SET @t = CAST(SUBSTRING(@x, @c + 1, 5) AS BIGINT) | |
SET @op = '' | |
WHILE @s < 8 | |
BEGIN | |
SET @q = @t % 32 | |
SET @op = CASE | |
WHEN @q BETWEEN 0 | |
AND 25 | |
THEN CHAR(@q + 65) | |
ELSE CHAR(@q + 24) | |
END + @op | |
SET @t = @t / 32 | |
SET @s = @s + 1 | |
END | |
SET @o = @o + @op | |
SET @c = @c + 5 | |
END | |
DECLARE @padc CHAR(1) | |
--padding section | |
SET @padc = CASE | |
WHEN @pad IS NULL | |
OR @pad = 1 | |
THEN '=' | |
ELSE '' | |
END | |
SET @o = CASE | |
WHEN @p = 1 | |
THEN SUBSTRING(@o, 1, DATALENGTH(@o) - 6) + REPLICATE(@padc, 6) | |
WHEN @p = 2 | |
THEN SUBSTRING(@o, 1, DATALENGTH(@o) - 4) + REPLICATE(@padc, 4) | |
WHEN @p = 3 | |
THEN SUBSTRING(@o, 1, DATALENGTH(@o) - 3) + REPLICATE(@padc, 3) | |
WHEN @p = 4 | |
THEN SUBSTRING(@o, 1, DATALENGTH(@o) - 1) + REPLICATE(@padc, 1) | |
ELSE @o | |
END | |
RETURN LTRIM(RTRIM(@o)) | |
END | |
GO | |
GRANT EXECUTE | |
ON [dbo].[base32enc] | |
TO PUBLIC | |
GO | |
IF EXISTS ( | |
SELECT * | |
FROM sys.objects | |
WHERE object_id = OBJECT_ID(N'[dbo].[base32dec]') | |
AND type IN ( | |
N'FN' | |
,N'IF' | |
,N'TF' | |
,N'FS' | |
,N'FT' | |
) | |
) | |
DROP FUNCTION [dbo].[base32dec] | |
GO | |
CREATE FUNCTION [dbo].[base32dec] (@x VARCHAR(max)) | |
RETURNS VARBINARY(max) | |
AS | |
BEGIN | |
/* RFC 4648 compliant BASE32 decoding function, takes varchar data to decode as only parameter*/ | |
DECLARE @p INT | |
DECLARE @c BIGINT | |
DECLARE @s BIGINT | |
DECLARE @q BIGINT | |
DECLARE @t BIGINT | |
DECLARE @o VARBINARY(max) | |
SET @o = CAST('' AS VARBINARY(max)) | |
SET @p = 0 --initialize padding character count | |
--we can strip off padding characters since BASE32 is unambiguous without them | |
SET @x = REPLACE(@x, '=', '') | |
SET @p = DATALENGTH(@x) % 8 --encode with 40-bit blocks | |
IF @p <> 0 | |
SET @x = @x + SUBSTRING('AAAAAAAA', 1, 8 - @p) | |
SET @x = UPPER(@x) | |
SET @x = REPLACE(@x, '1', 'I') | |
SET @x = REPLACE(@x, '0', 'O') | |
SET @c = 1 | |
WHILE @c < DATALENGTH(@x) + 1 | |
BEGIN | |
SET @s = 0 | |
SET @t = 0 | |
WHILE @s < 8 --accumulate 8 characters (40 bits) at a time in a bigint | |
BEGIN | |
SET @t = @t * 32 | |
SET @t = @t + CASE | |
WHEN SUBSTRING(@x, @c, 1) BETWEEN 'A' | |
AND 'Z' | |
THEN ASCII(SUBSTRING(@x, @c, 1)) - 65 | |
WHEN SUBSTRING(@x, @c, 1) BETWEEN '2' | |
AND '7' | |
THEN ASCII(SUBSTRING(@x, @c, 1)) - 24 | |
ELSE 0 | |
END | |
SET @s = @s + 1 | |
SET @c = @c + 1 | |
END | |
SET @o = @o + SUBSTRING(CAST(@t AS BINARY (8)), 4, 5) | |
END | |
--remove padding section | |
SET @o = CASE | |
WHEN @p = 2 | |
THEN SUBSTRING(@o, 1, DATALENGTH(@o) - 4) | |
WHEN @p = 4 | |
THEN SUBSTRING(@o, 1, DATALENGTH(@o) - 3) | |
WHEN @p = 5 | |
THEN SUBSTRING(@o, 1, DATALENGTH(@o) - 2) | |
WHEN @p = 7 | |
THEN SUBSTRING(@o, 1, DATALENGTH(@o) - 1) | |
ELSE @o | |
END | |
RETURN @o | |
END | |
GO | |
GRANT EXECUTE | |
ON [dbo].[base32dec] | |
TO PUBLIC | |
GO | |
/* | |
Copyright © 2012 Ryan Malayter. All Rights Reserved. | |
Redistribution and use in source and binary forms, with or without | |
modification, are permitted provided that the following conditions are | |
met: | |
1. Redistributions of source code must retain the above copyright | |
notice, this list of conditions and the following disclaimer. | |
2. Redistributions in binary form must reproduce the above copyright | |
notice, this list of conditions and the following disclaimer in the | |
documentation and/or other materials provided with the distribution. | |
3. The name of the author may not be used to endorse or promote products | |
derived from this software without specific prior written permission. | |
THIS SOFTWARE IS PROVIDED BY Ryan Malayter "AS IS" AND ANY EXPRESS OR | |
IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED | |
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE | |
DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, | |
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES | |
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR | |
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, | |
STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN | |
ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE | |
POSSIBILITY OF SUCH DAMAGE. | |
*/ |
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