but the pointer could just as easily overflow to -1, so that's broken too. allan
On Tue, Dec 9, 2008 at 10:48 AM, Mattias Ellert <mattias.ellert at fysast.uu.se> wrote: > m?n 2008-12-08 klockan 09:46 -0500 skrev m. allan noah: >> After some private mails with Ian, it seems this is a bug in sane-avision: >> >> during sane_cancel(), the backend calls: sanei_thread_kill >> (s->reader_pid), but s->reader_pid is 0, which signals the entire >> group. There is a test to try and avoid this, but it relies on prior >> code to have set s->reader_pid = -1, which has not happened in the >> case of no paper. >> >> I just expanded the test to require a positive value, since the pid >> should never be negative anyway? My fix has just been commited to CVS >> (backend version 289 nice round number for Ford and Studebaker fans). >> Ian and Rene- please test. >> >> allan > > This breaks the MacOS X port. The PID number (being a pointer) can be > arbitrary large, and when cast to an integer it can easily overflow to a > negative value. The code was fixed for this problem by removing all > places where the code was checking for a PID > 0. For the avision > backend this was done here: > > https://alioth.debian.org/plugins/scmcvs/cvsweb.php/sane-backends/backend/avision.c.diff?r1=1.38;r2=1.39;cvsroot=sane > > Your commit: > > https://alioth.debian.org/plugins/scmcvs/cvsweb.php/sane-backends/backend/avision.c.diff?r1=1.43;r2=1.44;cvsroot=sane > > reintroduces the problem fixed by the earlier commit. Please revert it > and fix the new problem in a way that doesn't break the MacOS X port. > > Mattias > > -- "The truth is an offense, but not a sin"
