# [PATCH] format-patch: notice failure to open cover letter for writing 4 messages from 2019-02-21 to 2019-02-22. Participants: Junio C Hamano, Jeff King, Duy Nguyen. Thread: https://gitlist.dev/t/50555 ## Junio C Hamano, 2019-02-21 23:50 Subject: [PATCH] format-patch: notice failure to open cover letter for writing Message-ID: URL: https://gitlist.dev/e/xmqqlg28snv0.fsf%40gitster-ct.c.googlers.com ``` The make_cover_letter() function is supposed to open a new file for writing, and let the caller write into it via FILE *rev->diffopt.file but because the function does not return anything, the caller does not bother checking the return value. Make sure it dies, instead of keep going with a NULL output filestream and relying on it to cause a crash. Signed-off-by: Junio C Hamano --- builtin/log.c | 2 +- t/t4014-format-patch.sh | 6 ++++++ 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/builtin/log.c b/builtin/log.c index 3e145fe502..43fc9a07df 100644 --- a/builtin/log.c +++ b/builtin/log.c @@ -1047,7 +1047,7 @@ static void make_cover_letter(struct rev_info *rev, int use_stdout, if (!use_stdout && open_next_file(NULL, rev->numbered_files ? NULL : "cover-letter", rev, quiet)) - return; + die(_("Failed to create cover-letter file")); log_write_email_headers(rev, head, &pp.after_subject, &need_8bit_cte, 0); diff --git a/t/t4014-format-patch.sh b/t/t4014-format-patch.sh index 909c743c13..b6e2fdbc44 100755 --- a/t/t4014-format-patch.sh +++ b/t/t4014-format-patch.sh @@ -589,6 +589,12 @@ test_expect_success 'excessive subject' ' ls patches/0004-This-is-an-excessively-long-subject-line-for-a-messa.patch ' +test_expect_success 'failure to write cover-letter aborts gracefully' ' + test_when_finished "rmdir 0000-cover-letter.patch" && + mkdir 0000-cover-letter.patch && + test_must_fail git format-patch --no-renames --cover-letter -1 +' + test_expect_success 'cover-letter inherits diff options' ' git mv file foo && git commit -m foo && ``` ## Jeff King, 2019-02-22 06:26 Subject: Re: [PATCH] format-patch: notice failure to open cover letter for writing Message-ID: <20190222062606.GD10248@sigill.intra.peff.net> URL: https://gitlist.dev/e/20190222062606.GD10248%40sigill.intra.peff.net In-Reply-To: ``` On Thu, Feb 21, 2019 at 03:50:11PM -0800, Junio C Hamano wrote: > The make_cover_letter() function is supposed to open a new file for > writing, and let the caller write into it via FILE *rev->diffopt.file > but because the function does not return anything, the caller does not > bother checking the return value. > > Make sure it dies, instead of keep going with a NULL output > filestream and relying on it to cause a crash. Definitely makes sense. > diff --git a/builtin/log.c b/builtin/log.c > index 3e145fe502..43fc9a07df 100644 > --- a/builtin/log.c > +++ b/builtin/log.c > @@ -1047,7 +1047,7 @@ static void make_cover_letter(struct rev_info *rev, int use_stdout, > > if (!use_stdout && > open_next_file(NULL, rev->numbered_files ? NULL : "cover-letter", rev, quiet)) > - return; > + die(_("Failed to create cover-letter file")); I wondered if we should be showing errno here, but it looks like open_next_file() will give us a more specific error (including errno if applicable). I'd suggest s/F/f/ in the message to match our usual style, though I see this code has a lot of capitalized errors already. :) > +test_expect_success 'failure to write cover-letter aborts gracefully' ' > + test_when_finished "rmdir 0000-cover-letter.patch" && > + mkdir 0000-cover-letter.patch && > + test_must_fail git format-patch --no-renames --cover-letter -1 > +' Cute test. :) -Peff ``` ## Duy Nguyen, 2019-02-22 07:50 Subject: Re: [PATCH] format-patch: notice failure to open cover letter for writing Message-ID: URL: https://gitlist.dev/e/CACsJy8A1cqWkomePW8i6veNT%2BWP2nq_kAZHay74ZgZFsz-d%2Bnw%40mail.gmail.com In-Reply-To: <20190222062606.GD10248@sigill.intra.peff.net> ``` On Fri, Feb 22, 2019 at 1:28 PM Jeff King wrote: > > diff --git a/builtin/log.c b/builtin/log.c > > index 3e145fe502..43fc9a07df 100644 > > --- a/builtin/log.c > > +++ b/builtin/log.c > > @@ -1047,7 +1047,7 @@ static void make_cover_letter(struct rev_info *rev, int use_stdout, > > > > if (!use_stdout && > > open_next_file(NULL, rev->numbered_files ? NULL : "cover-letter", rev, quiet)) > > - return; > > + die(_("Failed to create cover-letter file")); > > I'd suggest s/F/f/ in the message to match our usual style, though I see > this code has a lot of capitalized errors already. :) Thanks! The lowercase wins over uppercase [1] 1517 to 327. Unfortunately it's a tie in this file. But I think it's still good that new messages stick to lowercase. [1] counting error/warn/die only with git grep 'die[_a-z]*(_("[A-Z]\|error[_a-z]*(_("[A-Z]\|warning[_a-z]*(_("[A-Z]' -- \*.c -- Duy ``` ## Junio C Hamano, 2019-02-22 17:54 Subject: Re: [PATCH] format-patch: notice failure to open cover letter for writing Message-ID: URL: https://gitlist.dev/e/xmqqo973r9nk.fsf%40gitster-ct.c.googlers.com In-Reply-To: <20190222062606.GD10248@sigill.intra.peff.net> ``` Jeff King writes: > I'd suggest s/F/f/ in the message to match our usual style, though I see > this code has a lot of capitalized errors already. :) Yup, I'd prepare a prelim clean-up before this step. >> +test_expect_success 'failure to write cover-letter aborts gracefully' ' >> + test_when_finished "rmdir 0000-cover-letter.patch" && >> + mkdir 0000-cover-letter.patch && >> + test_must_fail git format-patch --no-renames --cover-letter -1 >> +' > > Cute test. :) Those who can find this "cute" would probably know, but for others, this is a trick to test codepath for "cannot create a file" error without requiring SANITY prerequisite. ```