Thanks to Jernej Simoncic for these:

Also, here are the declarations for kunzip.dll for use with Inno Setup
<http://www.jrsoftware.org/isinfo.php>. I have tested the first 4, but the
rest should work, too:

function kunzip_inflate_init(): Integer; external
'kunzip_inflate_init@files:kunzip.dll cdecl';
function kunzip_inflate_free(): Integer; external
'kunzip_inflate_free@files:kunzip.dll cdecl';
function kunzip_get_name(Filename, Name: String; Offset: Integer): Integer;
external 'kunzip_get_name@files:kunzip.dll cdecl';
function kunzip_next(Filename,Basedir: String; Offset: Integer): Integer;
external 'kunzip_next@files:kunzip.dll cdecl';

function kunzip_count_files(FileName: String): Integer; external
'kunzip_count_files@files:kunzip.dll cdecl';
function kunzip_all(FileName, BaseDir: String): Integer; external
'kunzip_all@files:kunzip.dll cdecl';
function kunzip_get_version(Version: String): Integer; external
'kunzip_get_version@files:kunzip.dll cdecl';
function kunzip_print_version(): Integer; external
'kunzip_print_version@files:kunzip.dll cdecl';