The input buffer is initialised to a reasonable size and extended
if necessary. When this happened the offset into the buffer wasn't
reset to zero so subsequent lines were appended to the long line.
Fix this and add some tests.
function old new delta
rev_main 377 368 -9
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(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-9) Total: -9 bytes
Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
