Hi Junio, On Tue, 21 Jun 2016, Junio C Hamano wrote: > Junio C Hamano <gitster@xxxxxxxxx> writes: > > > Junio C Hamano <gitster@xxxxxxxxx> writes: > > > >> Johannes Schindelin <johannes.schindelin@xxxxxx> writes: > >> > >>> We are about to teach the log_tree machinery to reuse the diffopt.file > >>> setting to output to a file stream different from stdout. > >>> > >>> This means that builtin am can no longer ask the diff machinery to > >>> close the file when actually calling the log_tree machinery (which > >>> wants to flush the very same file stream that would then already be > >>> closed). > >> > >> Sorry for being slow, but I am not sure why the first paragraph has > >> to mean the second paragraph. This existing caller opens a new > >> stream, sets .fp to it, and expects that the log_tree_commit() to > >> close it if told by setting .close_file to true, all of which sounds > >> sensible. > >> > >> If a codepath wants to use the same stream for two or more calls to > >> log_tree by pointing the stream with .fp, it would be of course a > >> problem for the caller to set .close_file to true in its first call, > >> as .fp will be closed and no longer usable for second and subsequent > >> call, and that would be a bug, but for a single-shot call it feels > >> entirely a sensible request to make, no? > >> > >> Obviously you have looked at the codepaths involved a lot longer > >> than I did, and I do not doubt your conclusion, but I cannot quite > >> convince myself with the above explanation. > >> > >> The option parser of "git diff" family sets ->close_file to true > >> when the --output option is given. > >> > >> Wouldn't this patch break "git log --output=foo -3"? > > > > I wonder if the right approach is to stop using .close_file > > everywhere. > > > > With this "do not set .close_file if you use log_tree_commit()", > > "git log --output=/dev/stdout -3" gets broken, but removing that > > check is not sufficient to correct the same command with "-p", as > > letting .close_file to close the output file after finishing a > > single diff would mean that subsequent write to the same file > > descriptor will trigger a failure. > > We could say "git log --output=foo -3 [-p]" without any of your > patches is already broken, and it is a valid excuse to take this > change that we are not making things worse with it. > > It is just 3/9 is a logical first step to correct that exact > problem, i.e. some codepaths, even though there is a place that > holds the output stream and command line parser does prepare one for > "foo" when --output=foo is given, ignore it and send thigns to the > standard output stream. You might not have written 3/9 in order to > fix that "git log --output=foo" problem, but a fix for it should > look exactly like your 3/9, I would think. > > And it is sad that this step makes that fix impossible. Okay, I ended up seeing that there is no way I can avoid Doing The Right Thing. It is not quite as pretty as I hoped it would be (callers of log_tree_commit() that want to call it in a loop still have to override close_file manually), but it does produce a nicer story. Please see the fixes in the latest iteration I just sent out. Ciao, Dscho -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html