Convert 'C' function to SQL

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Project Budget (USD)
$10 - $30

Project Description:
I want to convert the PHP function "SIMILAR_TEXT" into an SQL (preferably MYSQL) Function that returns a % match.
SIMILAR_TEXT is a fuzzy string matching function, but I want to use it via MYSQL, and to also return a % match.
You can try it out here :

The function is very small, and written in 'C'. The original C code is attached within the 'string.c' file.
A simpler version in pure 'C' in the attached 'c_version.txt' file.

The end result should be a MYSQL (or SQL) FUNCTION of the type FN_SIMILAR_TEXT(str1, str2) RETURNS FLOAT;
that returns the % match between the two strings.

Skills required:
C Programming, MySQL, PHP, SQL
Additional Files: c_version.txt string.c
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