marmoute created this revision. Herald added a reviewer: indygreg. Herald added a reviewer: hg-reviewers. Herald added a subscriber: mercurial-patches.
REVISION SUMMARY The code doing actual writing is already doing the necessary seeking, so we could safely use 'r+'. This make the file objecs usable in more situation, like updating the sidedata information during pull. revlog: forcibly move the file cursor at the right location before writing This is a paranoid change in case the changelog computation moved the cursors under our feets. This is not known to happens right now. REPOSITORY rHG Mercurial BRANCH default REVISION DETAIL https://phab.mercurial-scm.org/D10608 AFFECTED FILES mercurial/revlog.py mercurial/store.py CHANGE DETAILS diff --git a/mercurial/store.py b/mercurial/store.py --- a/mercurial/store.py +++ b/mercurial/store.py @@ -706,7 +706,7 @@ # do not trigger a fncache load when adding a file that already is # known to exist. notload = self.fncache.entries is None and self.vfs.exists(encoded) - if notload and b'a' in mode and not self.vfs.stat(encoded).st_size: + if notload and b'r+' in mode and not self.vfs.stat(encoded).st_size: # when appending to an existing file, if the file has size zero, # it should be considered as missing. Such zero-size files are # the result of truncation when a transaction is aborted. diff --git a/mercurial/revlog.py b/mercurial/revlog.py --- a/mercurial/revlog.py +++ b/mercurial/revlog.py @@ -2016,7 +2016,7 @@ if existing_handles: # switched from inline to conventional reopen the index - ifh = self._indexfp(b"a+") + ifh = self._indexfp(b"r+") self._writinghandles = (ifh, new_dfh) new_dfh = None finally: @@ -2037,11 +2037,23 @@ dsize = self.end(r - 1) dfh = None if not self._inline: - dfh = self._datafp(b"a+") + try: + dfh = self._datafp(b"r+") + dfh.seek(0, os.SEEK_END) + except IOError as inst: + if inst.errno != errno.ENOENT: + raise + dfh = self._datafp(b"w+") transaction.add(self._datafile, dsize) try: isize = r * self.index.entry_size - ifh = self._indexfp(b"a+") + try: + ifh = self._indexfp(b"r+") + ifh.seek(0, os.SEEK_END) + except IOError as inst: + if inst.errno != errno.ENOENT: + raise + ifh = self._indexfp(b"w+") if self._inline: transaction.add(self._indexfile, dsize + isize) else: @@ -3174,6 +3186,8 @@ entry = (new_offset_flags,) + entry[1:8] entry += (current_offset, len(serialized_sidedata)) + # the sidedata computation might have move the file cursors around + dfh.seek(current_offset, os.SEEK_SET) dfh.write(serialized_sidedata) new_entries.append(entry) current_offset += len(serialized_sidedata) To: marmoute, indygreg, #hg-reviewers Cc: mercurial-patches, mercurial-devel _______________________________________________ Mercurial-devel mailing list Mercurial-devel@mercurial-scm.org https://www.mercurial-scm.org/mailman/listinfo/mercurial-devel
