comparison mercurial/branchmap.py @ 28557:4b83507bfc91

cache: safer handling of failing seek when writing revision branch cache

If the seek for some reason fails (perhaps because the file is too short to
search to the requested position), make sure we seek to the start and rewrite
everything.

It is unknown if this fixes a real problem that ever happened.

28556:0706d60d070f

            try:
                f = repo.vfs.open(_rbcrevs, 'ab')
                if f.tell() != start:
                    repo.ui.debug("truncating %s to %s\n" % (_rbcrevs, start))
                    f.seek(start)
                    f.truncate()
                end = revs * _rbcrecsize
                f.write(self._rbcrevs[start:end])
                f.close()
            except (IOError, OSError, error.Abort) as inst:

28557:4b83507bfc91

            try:
                f = repo.vfs.open(_rbcrevs, 'ab')
                if f.tell() != start:
                    repo.ui.debug("truncating %s to %s\n" % (_rbcrevs, start))
                    f.seek(start)
                    if f.tell() != start:
                        start = 0
                        f.seek(start)
                    f.truncate()
                end = revs * _rbcrecsize
                f.write(self._rbcrevs[start:end])
                f.close()
            except (IOError, OSError, error.Abort) as inst: