From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Petazzoni Date: Mon, 27 Nov 2017 22:08:49 +0100 Subject: [Buildroot] potential divide by zero in support/scripts/size-stats In-Reply-To: References: Message-ID: <20171127220849.5f62e6fc@windsurf.home> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net Hello, On Sat, 11 Nov 2017 18:17:36 -0800, Andrey Yurovsky wrote: > I see a divide by zero exception in support/scripts/size-stats when I > use the graph-size target, the package of size zero causing this is > skeleton-init-systemd which I worked out by catching the exception. Is > this package erroneously of size zero or should that be OK? Thanks for reporting this bug and proposing a fix! I have some comments on the implementation, but first about the format: the commit log should contain a Signed-off-by line with your name and e-mail, and the commit log should not be formatted as a personal message, but rather as a description of what is being changed/fixed. Also the first line should look like: "support/scripts/size-stats: ..." > diff --git a/support/scripts/size-stats b/support/scripts/size-stats > index af45000..3cd6838 100755 > --- a/support/scripts/size-stats > +++ b/support/scripts/size-stats > @@ -178,9 +178,12 @@ def gen_files_csv(filesdict, pkgsizes, outputf): > "File size in system (%)"]) > for f, (pkgname, filesize) in filesdict.items(): > pkgsize = pkgsizes[pkgname] > - wr.writerow([f, pkgname, filesize, pkgsize, > - "%.1f" % (float(filesize) / pkgsize * 100), > - "%.1f" % (float(filesize) / total * 100)]) > + try: > + wr.writerow([f, pkgname, filesize, pkgsize, > + "%.1f" % (float(filesize) / pkgsize * 100), > + "%.1f" % (float(filesize) / total * 100)]) > + except ZeroDivisionError: > + print('WARNING: \"%s\" is size 0!' % pkgname) I don't think we want to skip files from zero-sized packages: we want to see them in the CSV. So perhaps something like: if pkgsize != 0: percent_pkg = float(filesize) / pkgsize * 100 else: percent_pkg = 0 percent_total = float(filesize) / total * 100 wr.writerow([f, pkgname, filesize, pkgsize, "%.1f" % percent_pkg, "%.1f" % percent_total]) Could you test it, and resubmit as a new patch, with your Signed-off-by? Thanks a lot! Thomas Petazzoni -- Thomas Petazzoni, CTO, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com