ar: reuse existing ar unpacking code
get_header_tar: handle autodetection for tiny .tar.gz files too
unarchive.h: do not include CONFIGed out things
function old new delta
get_header_tar 1521 1534 +13
dpkg_deb_main 400 380 -20
ar_main 260 196 -64
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(add/remove: 0/0 grow/shrink: 1/2 up/down: 13/-84) Total: -71 bytes
open_transformer(), common code for pipe+fork.
Function pointer for read() no longer needed.
Allow inflate to be initialised with a specified buffer size to avoid
over-reading.
Reset static variables in inflate_get_next_window to fix a bug where
only the first file in a .zip would be be extracted.