[ft] Regression tests for integer overflow

[snteam snteam]

Hai,
I want to write regression tests for the fixes in 2.2.1 version.

* src/bdf/bdflib.c (setsbit, sbitset): Handle values >= 128
	gracefully.
	(_bdf_set_default_spacing): Increase `name' buffer size to 256 and
	issue an error for longer names.  This fixes CVE-2007-1351.
	(_bdf_parse_glyphs): Limit allowed number of glyphs in font to the
	number of code points in Unicode.

For this which library I need to include? And which High level functions I need to use?
Can you please help me in this regrad

Thanks,
Lavanya