Message ID | 20241009135747.3563204-3-bence@ferdinandy.com (mailing list archive) |
---|---|
State | Superseded |
Headers | show |
Series | [v5,1/6] refs_update_symref: atomically record overwritten ref | expand |
Bence Ferdinandy <bence@ferdinandy.com> writes: > +static void report_auto(const char *remote, const char *head_name, > + struct strbuf *buf_prev) { > + struct strbuf buf_prefix = STRBUF_INIT; > + const char *prev_head; I think we need to initialize prev_head to NULL. > + strbuf_addf(&buf_prefix, "refs/remotes/%s/", remote); > + skip_prefix(buf_prev->buf, buf_prefix.buf, &prev_head); If the symref was not pointing into the "refs/remotes/<remote>/" hierarchy previously, skip_prefix() comes back without touching prev_head (i.e. not starting with the prefix does not clear it). Assuming that we fix the initialization, the rest of the function looks more or less correct. > + if (prev_head && !strcmp(prev_head, head_name)) > + printf("'%s/HEAD' is unchanged and points to '%s'\n", > + remote, head_name); > + else if (prev_head) > + printf("'%s/HEAD' has changed from '%s' and now points to '%s'\n", > + remote, prev_head, head_name); > + else > + printf("'%s/HEAD' is now created and points to '%s'\n", > + remote, head_name); The "more or less" part is that the message does not let you tell between refs/remotes/<name>/HEAD that did not exist, and refs/remotes/<name>/HEAD that used to point at somewhere unexpected, outside refs/remotes/<name>/ hierarchy. For that, we can check if buf_prev->len is 0 (in which case, the "now created and points at" applies) or non-zero (in which case, we say something like "used to point at '%s' (which is unusual), but now points at '%s' as requested").
Junio C Hamano <gitster@pobox.com> writes: > Bence Ferdinandy <bence@ferdinandy.com> writes: > >> +static void report_auto(const char *remote, const char *head_name, >> + struct strbuf *buf_prev) { >> + struct strbuf buf_prefix = STRBUF_INIT; >> + const char *prev_head; > > I think we need to initialize prev_head to NULL. > >> + strbuf_addf(&buf_prefix, "refs/remotes/%s/", remote); >> + skip_prefix(buf_prev->buf, buf_prefix.buf, &prev_head); > > If the symref was not pointing into the "refs/remotes/<remote>/" > hierarchy previously, skip_prefix() comes back without touching > prev_head (i.e. not starting with the prefix does not clear it). The two uninitialized prev_head were also noticed by compilers in multiple jobs at GitHub CI. https://github.com/git/git/actions/runs/11265515664
On 10/10/2024 16:57, Junio C Hamano wrote: > Junio C Hamano <gitster@pobox.com> writes: > >> Bence Ferdinandy <bence@ferdinandy.com> writes: >> >>> +static void report_auto(const char *remote, const char *head_name, >>> + struct strbuf *buf_prev) { >>> + struct strbuf buf_prefix = STRBUF_INIT; >>> + const char *prev_head; >> >> I think we need to initialize prev_head to NULL. >> >>> + strbuf_addf(&buf_prefix, "refs/remotes/%s/", remote); >>> + skip_prefix(buf_prev->buf, buf_prefix.buf, &prev_head); >> >> If the symref was not pointing into the "refs/remotes/<remote>/" >> hierarchy previously, skip_prefix() comes back without touching >> prev_head (i.e. not starting with the prefix does not clear it). > > The two uninitialized prev_head were also noticed by compilers in > multiple jobs at GitHub CI. > > https://github.com/git/git/actions/runs/11265515664 Heh, I was just about to send a patch to fix up these two warnings (errors with -Werror), so that I could build 'seen'. However, it seems to be well in hand, so I won't bother! :) ATB, Ramsay Jones
On Thu Oct 10, 2024 at 17:57, Junio C Hamano <gitster@pobox.com> wrote: > Junio C Hamano <gitster@pobox.com> writes: > >> Bence Ferdinandy <bence@ferdinandy.com> writes: >> >>> +static void report_auto(const char *remote, const char *head_name, >>> + struct strbuf *buf_prev) { >>> + struct strbuf buf_prefix = STRBUF_INIT; >>> + const char *prev_head; >> >> I think we need to initialize prev_head to NULL. >> >>> + strbuf_addf(&buf_prefix, "refs/remotes/%s/", remote); >>> + skip_prefix(buf_prev->buf, buf_prefix.buf, &prev_head); >> >> If the symref was not pointing into the "refs/remotes/<remote>/" >> hierarchy previously, skip_prefix() comes back without touching >> prev_head (i.e. not starting with the prefix does not clear it). > > The two uninitialized prev_head were also noticed by compilers in > multiple jobs at GitHub CI. > > https://github.com/git/git/actions/runs/11265515664 I wonder why that didn't fail the build for me locally. I was running make -j8 install PREFIX=$HOME/.local for testing. Should I have added a flag or ENV variable somewhere? Anyhow, the v6 I sent earlier today should fix this (and hopefully all your other comments as well). Thanks, Bence
diff --git a/builtin/remote.c b/builtin/remote.c index 353ffd2c43..2480128b88 100644 --- a/builtin/remote.c +++ b/builtin/remote.c @@ -1399,10 +1399,30 @@ static int show(int argc, const char **argv, const char *prefix) return result; } +static void report_auto(const char *remote, const char *head_name, + struct strbuf *buf_prev) { + struct strbuf buf_prefix = STRBUF_INIT; + const char *prev_head; + + strbuf_addf(&buf_prefix, "refs/remotes/%s/", remote); + skip_prefix(buf_prev->buf, buf_prefix.buf, &prev_head); + + if (prev_head && !strcmp(prev_head, head_name)) + printf("'%s/HEAD' is unchanged and points to '%s'\n", + remote, head_name); + else if (prev_head) + printf("'%s/HEAD' has changed from '%s' and now points to '%s'\n", + remote, prev_head, head_name); + else + printf("'%s/HEAD' is now created and points to '%s'\n", + remote, head_name); +} + static int set_head(int argc, const char **argv, const char *prefix) { int i, opt_a = 0, opt_d = 0, result = 0; - struct strbuf buf = STRBUF_INIT, buf2 = STRBUF_INIT; + struct strbuf buf = STRBUF_INIT, buf2 = STRBUF_INIT, + buf_prev = STRBUF_INIT; char *head_name = NULL; struct ref_store *refs = get_main_ref_store(the_repository); @@ -1445,15 +1465,17 @@ static int set_head(int argc, const char **argv, const char *prefix) /* make sure it's valid */ if (!refs_ref_exists(refs, buf2.buf)) result |= error(_("Not a valid ref: %s"), buf2.buf); - else if (refs_update_symref(refs, buf.buf, buf2.buf, "remote set-head", NULL)) + else if (refs_update_symref(refs, buf.buf, buf2.buf, "remote set-head", &buf_prev)) result |= error(_("Could not setup %s"), buf.buf); - else if (opt_a) - printf("%s/HEAD set to %s\n", argv[0], head_name); + else if (opt_a) { + report_auto(argv[0], head_name, &buf_prev); + } free(head_name); } strbuf_release(&buf); strbuf_release(&buf2); + strbuf_release(&buf_prev); return result; } diff --git a/t/t5505-remote.sh b/t/t5505-remote.sh index 532035933f..262a4de0aa 100755 --- a/t/t5505-remote.sh +++ b/t/t5505-remote.sh @@ -434,7 +434,7 @@ test_expect_success 'set-head --auto has no problem w/multiple HEADs' ' cd test && git fetch two "refs/heads/*:refs/remotes/two/*" && git remote set-head --auto two >output 2>&1 && - echo "two/HEAD set to main" >expect && + echo "'\''two/HEAD'\'' is unchanged and points to '\''main'\''" >expect && test_cmp expect output ) ' @@ -453,6 +453,17 @@ test_expect_success 'set-head explicit' ' ) ' + +test_expect_success 'set-head --auto reports change' ' + ( + cd test && + git remote set-head origin side2 && + git remote set-head --auto origin >output 2>&1 && + echo "'\''origin/HEAD'\'' has changed from '\''side2'\'' and now points to '\''main'\''" >expect && + test_cmp expect output + ) +' + cat >test/expect <<EOF Pruning origin URL: $(pwd)/one
Currently, set-head --auto will print a message saying "remote/HEAD set to branch", which implies something was changed. Change the output of --auto, so the output actually reflects what was done: a) set a previously unset HEAD, b) change HEAD because remote changed or c) no updates. Signed-off-by: Bence Ferdinandy <bence@ferdinandy.com> --- Notes: v1-v2: was RFC in https://lore.kernel.org/git/20240910203835.2288291-1-bence@ferdinandy.com/ v3: This patch was originally sent along when I thought set-head was going to be invoked by fetch, but the discussion on the RFC concluded that it should be not. This opened the possibility to make it more explicit. Note: although I feel both things the patch does are really just cosmetic, an argument could be made for breaking it into two, one for the no-op part and one for the --auto print update. Was sent in: https://lore.kernel.org/git/20240915221055.904107-1-bence@ferdinandy.com/ v4: - changes are now handled atomically via the ref update transaction - outputs have changed along the lines of Junio's suggestion - minor refactor to set_head for improved legibility v5: - the minor refactor has been split out into its own patch builtin/remote.c | 30 ++++++++++++++++++++++++++---- t/t5505-remote.sh | 13 ++++++++++++- 2 files changed, 38 insertions(+), 5 deletions(-)