From 7dd4051b014741732271785c0915599b1f0c1a47 Mon Sep 17 00:00:00 2001 From: Karthik Nayak Date: Fri, 7 Jun 2024 15:33:04 +0200 Subject: [PATCH] update-ref: add support for 'symref-update' command Add 'symref-update' command to the '--stdin' mode of 'git-update-ref' to allow updates of symbolic refs. The 'symref-update' command takes in a , which the will be updated to. If the doesn't exist it will be created. It also optionally takes either an `ref ` or `oid `. If the is provided, it checks to see if the targets the before the update. If is provided it checks to ensure that it is a regular ref and is the OID before the update. This by extension also means that this when a zero is provided, it ensures that the ref didn't exist before. The divergence in syntax from the regular `update` command is because if we don't use a `(ref | oid)` prefix for the old_value, then there is ambiguity around if the value provided should be treated as an oid or a reference. This is more so the reason, because we allow anything committish to be provided as an oid. While 'symref-verify' and 'symref-delete' also take in `` we do not have this divergence there as those commands only work with symrefs. Whereas 'symref-update' also works with regular refs and allows users to convert regular refs to symrefs. The command allows users to perform symbolic ref updates within a transaction. This provides atomicity and allows users to perform a set of operations together. This command supports deref mode, to ensure that we can update dereferenced regular refs to symrefs. Helped-by: Patrick Steinhardt Helped-by: Junio C Hamano Signed-off-by: Karthik Nayak Signed-off-by: Junio C Hamano --- Documentation/git-update-ref.txt | 7 ++ builtin/update-ref.c | 92 ++++++++++++++ t/t1400-update-ref.sh | 203 +++++++++++++++++++++++++++++++ t/t1416-ref-transaction-hooks.sh | 4 + 4 files changed, 306 insertions(+) diff --git a/Documentation/git-update-ref.txt b/Documentation/git-update-ref.txt index 364ef78af1..afcf33cf60 100644 --- a/Documentation/git-update-ref.txt +++ b/Documentation/git-update-ref.txt @@ -65,6 +65,7 @@ performs all modifications together. Specify commands of the form: create SP SP LF delete SP [SP ] LF verify SP [SP ] LF + symref-update SP SP [SP (ref SP | oid SP )] LF symref-create SP SP LF symref-delete SP [SP ] LF symref-verify SP [SP ] LF @@ -89,6 +90,7 @@ quoting: create SP NUL NUL delete SP NUL [] NUL verify SP NUL [] NUL + symref-update SP NUL [NUL (ref NUL | oid NUL )] NUL symref-create SP NUL NUL symref-delete SP [NUL ] NUL symref-verify SP [NUL ] NUL @@ -119,6 +121,11 @@ delete:: Delete after verifying it exists with , if given. If given, may not be zero. +symref-update:: + Set to after verifying or , + if given. Specify a zero to ensure that the ref does not + exist before the update. + verify:: Verify against but do not change it. If is zero or missing, the ref must not exist. diff --git a/builtin/update-ref.c b/builtin/update-ref.c index 989c0ebc5f..d3cfae64ed 100644 --- a/builtin/update-ref.c +++ b/builtin/update-ref.c @@ -98,6 +98,42 @@ static char *parse_next_refname(const char **next) return parse_refname(next); } +/* + * Wrapper around parse_arg which skips the next delimiter. + */ +static char *parse_next_arg(const char **next) +{ + struct strbuf arg = STRBUF_INIT; + + if (line_termination) { + /* Without -z, consume SP and use next argument */ + if (!**next || **next == line_termination) + return NULL; + if (**next != ' ') + die("expected SP but got: %s", *next); + } else { + /* With -z, read the next NUL-terminated line */ + if (**next) + return NULL; + } + /* Skip the delimiter */ + (*next)++; + + if (line_termination) { + /* Without -z, use the next argument */ + *next = parse_arg(*next, &arg); + } else { + /* With -z, use everything up to the next NUL */ + strbuf_addstr(&arg, *next); + *next += arg.len; + } + + if (arg.len) + return strbuf_detach(&arg, NULL); + + strbuf_release(&arg); + return NULL; +} /* * The value being parsed is (as opposed to ; the @@ -237,6 +273,61 @@ static void parse_cmd_update(struct ref_transaction *transaction, strbuf_release(&err); } +static void parse_cmd_symref_update(struct ref_transaction *transaction, + const char *next, const char *end) +{ + char *refname, *new_target, *old_arg; + char *old_target = NULL; + struct strbuf err = STRBUF_INIT; + struct object_id old_oid; + int have_old_oid = 0; + + refname = parse_refname(&next); + if (!refname) + die("symref-update: missing "); + + new_target = parse_next_refname(&next); + if (!new_target) + die("symref-update %s: missing ", refname); + + old_arg = parse_next_arg(&next); + if (old_arg) { + old_target = parse_next_arg(&next); + if (!old_target) + die("symref-update %s: expected old value", refname); + + if (!strcmp(old_arg, "oid")) { + if (repo_get_oid(the_repository, old_target, &old_oid)) + die("symref-update %s: invalid oid: %s", refname, old_target); + + have_old_oid = 1; + } else if (!strcmp(old_arg, "ref")) { + if (check_refname_format(old_target, REFNAME_ALLOW_ONELEVEL)) + die("symref-update %s: invalid ref: %s", refname, old_target); + } else { + die("symref-update %s: invalid arg '%s' for old value", refname, old_arg); + } + } + + if (*next != line_termination) + die("symref-update %s: extra input: %s", refname, next); + + if (ref_transaction_update(transaction, refname, NULL, + have_old_oid ? &old_oid : NULL, + new_target, + have_old_oid ? NULL : old_target, + update_flags | create_reflog_flag, + msg, &err)) + die("%s", err.buf); + + update_flags = default_flags; + free(refname); + free(old_arg); + free(old_target); + free(new_target); + strbuf_release(&err); +} + static void parse_cmd_create(struct ref_transaction *transaction, const char *next, const char *end) { @@ -502,6 +593,7 @@ static const struct parse_cmd { { "create", parse_cmd_create, 2, UPDATE_REFS_OPEN }, { "delete", parse_cmd_delete, 2, UPDATE_REFS_OPEN }, { "verify", parse_cmd_verify, 2, UPDATE_REFS_OPEN }, + { "symref-update", parse_cmd_symref_update, 4, UPDATE_REFS_OPEN }, { "symref-create", parse_cmd_symref_create, 2, UPDATE_REFS_OPEN }, { "symref-delete", parse_cmd_symref_delete, 2, UPDATE_REFS_OPEN }, { "symref-verify", parse_cmd_symref_verify, 2, UPDATE_REFS_OPEN }, diff --git a/t/t1400-update-ref.sh b/t/t1400-update-ref.sh index 79f029ad22..d662ab3508 100755 --- a/t/t1400-update-ref.sh +++ b/t/t1400-update-ref.sh @@ -1360,6 +1360,7 @@ test_expect_success 'fails with duplicate HEAD update' ' ' test_expect_success 'fails with duplicate ref update via symref' ' + test_when_finished "git symbolic-ref -d refs/heads/symref2" && git branch target2 $A && git symbolic-ref refs/heads/symref2 refs/heads/target2 && cat >stdin <<-EOF && @@ -1862,6 +1863,208 @@ do git reflog exists refs/heads/symref ' + test_expect_success "stdin $type symref-update fails with too many arguments" ' + format_command $type "symref-update refs/heads/symref" "$a" "ref" "$a" "$a" >stdin && + test_must_fail git update-ref --stdin $type --no-deref err && + if test "$type" = "-z" + then + grep "fatal: unknown command: $a" err + else + grep "fatal: symref-update refs/heads/symref: extra input: $a" err + fi + ' + + test_expect_success "stdin $type symref-update fails with wrong old value argument" ' + format_command $type "symref-update refs/heads/symref" "$a" "foo" "$a" "$a" >stdin && + test_must_fail git update-ref --stdin $type --no-deref err && + grep "fatal: symref-update refs/heads/symref: invalid arg ${SQ}foo${SQ} for old value" err + ' + + test_expect_success "stdin $type symref-update creates with zero old value" ' + test_when_finished "git symbolic-ref -d refs/heads/symref" && + format_command $type "symref-update refs/heads/symref" "$a" "oid" "$Z" >stdin && + git update-ref --stdin $type --no-deref expect && + git symbolic-ref refs/heads/symref >actual && + test_cmp expect actual + ' + + test_expect_success "stdin $type symref-update creates with no old value" ' + test_when_finished "git symbolic-ref -d refs/heads/symref" && + format_command $type "symref-update refs/heads/symref" "$a" >stdin && + git update-ref --stdin $type --no-deref expect && + git symbolic-ref refs/heads/symref >actual && + test_cmp expect actual + ' + + test_expect_success "stdin $type symref-update creates dangling" ' + test_when_finished "git symbolic-ref -d refs/heads/symref" && + test_must_fail git rev-parse refs/heads/nonexistent && + format_command $type "symref-update refs/heads/symref" "refs/heads/nonexistent" >stdin && + git update-ref --stdin $type --no-deref expect && + git symbolic-ref refs/heads/symref >actual && + test_cmp expect actual + ' + + test_expect_success "stdin $type symref-update fails with wrong old value" ' + test_when_finished "git symbolic-ref -d refs/heads/symref" && + git symbolic-ref refs/heads/symref $a && + format_command $type "symref-update refs/heads/symref" "$m" "ref" "$b" >stdin && + test_must_fail git update-ref --stdin $type --no-deref err && + grep "fatal: verifying symref target: ${SQ}refs/heads/symref${SQ}: is at $a but expected $b" err && + test_must_fail git rev-parse --verify -q $c + ' + + test_expect_success "stdin $type symref-update updates dangling ref" ' + test_when_finished "git symbolic-ref -d refs/heads/symref" && + test_must_fail git rev-parse refs/heads/nonexistent && + git symbolic-ref refs/heads/symref refs/heads/nonexistent && + format_command $type "symref-update refs/heads/symref" "$a" >stdin && + git update-ref --stdin $type --no-deref expect && + git symbolic-ref refs/heads/symref >actual && + test_cmp expect actual + ' + + test_expect_success "stdin $type symref-update updates dangling ref with old value" ' + test_when_finished "git symbolic-ref -d refs/heads/symref" && + test_must_fail git rev-parse refs/heads/nonexistent && + git symbolic-ref refs/heads/symref refs/heads/nonexistent && + format_command $type "symref-update refs/heads/symref" "$a" "ref" "refs/heads/nonexistent" >stdin && + git update-ref --stdin $type --no-deref expect && + git symbolic-ref refs/heads/symref >actual && + test_cmp expect actual + ' + + test_expect_success "stdin $type symref-update fails update dangling ref with wrong old value" ' + test_when_finished "git symbolic-ref -d refs/heads/symref" && + test_must_fail git rev-parse refs/heads/nonexistent && + git symbolic-ref refs/heads/symref refs/heads/nonexistent && + format_command $type "symref-update refs/heads/symref" "$a" "ref" "refs/heads/wrongref" >stdin && + test_must_fail git update-ref --stdin $type --no-deref expect && + git symbolic-ref refs/heads/symref >actual && + test_cmp expect actual + ' + + test_expect_success "stdin $type symref-update works with right old value" ' + test_when_finished "git symbolic-ref -d refs/heads/symref" && + git symbolic-ref refs/heads/symref $a && + format_command $type "symref-update refs/heads/symref" "$m" "ref" "$a" >stdin && + git update-ref --stdin $type --no-deref expect && + git symbolic-ref refs/heads/symref >actual && + test_cmp expect actual + ' + + test_expect_success "stdin $type symref-update works with no old value" ' + test_when_finished "git symbolic-ref -d refs/heads/symref" && + git symbolic-ref refs/heads/symref $a && + format_command $type "symref-update refs/heads/symref" "$m" >stdin && + git update-ref --stdin $type --no-deref expect && + git symbolic-ref refs/heads/symref >actual && + test_cmp expect actual + ' + + test_expect_success "stdin $type symref-update fails with empty old ref-target" ' + test_when_finished "git symbolic-ref -d refs/heads/symref" && + git symbolic-ref refs/heads/symref $a && + format_command $type "symref-update refs/heads/symref" "$m" "ref" "" >stdin && + test_must_fail git update-ref --stdin $type --no-deref expect && + git symbolic-ref refs/heads/symref >actual && + test_cmp expect actual + ' + + test_expect_success "stdin $type symref-update creates (with deref)" ' + test_when_finished "git symbolic-ref -d refs/heads/symref" && + format_command $type "symref-update refs/heads/symref" "$a" >stdin && + git update-ref --stdin $type expect && + git symbolic-ref --no-recurse refs/heads/symref >actual && + test_cmp expect actual && + test-tool ref-store main for-each-reflog-ent refs/heads/symref >actual && + grep "$Z $(git rev-parse $a)" actual + ' + + test_expect_success "stdin $type symref-update regular ref to symref with correct old-oid" ' + test_when_finished "git symbolic-ref -d --no-recurse refs/heads/regularref" && + git update-ref --no-deref refs/heads/regularref $a && + format_command $type "symref-update refs/heads/regularref" "$a" "oid" "$(git rev-parse $a)" >stdin && + git update-ref --stdin $type expect && + git symbolic-ref --no-recurse refs/heads/regularref >actual && + test_cmp expect actual && + test-tool ref-store main for-each-reflog-ent refs/heads/regularref >actual && + grep "$(git rev-parse $a) $(git rev-parse $a)" actual + ' + + test_expect_success "stdin $type symref-update regular ref to symref fails with wrong old-oid" ' + test_when_finished "git update-ref -d refs/heads/regularref" && + git update-ref --no-deref refs/heads/regularref $a && + format_command $type "symref-update refs/heads/regularref" "$a" "oid" "$(git rev-parse refs/heads/target2)" >stdin && + test_must_fail git update-ref --stdin $type err && + grep "fatal: cannot lock ref ${SQ}refs/heads/regularref${SQ}: is at $(git rev-parse $a) but expected $(git rev-parse refs/heads/target2)" err && + echo $(git rev-parse $a) >expect && + git rev-parse refs/heads/regularref >actual && + test_cmp expect actual + ' + + test_expect_success "stdin $type symref-update regular ref to symref fails with invalid old-oid" ' + test_when_finished "git update-ref -d refs/heads/regularref" && + git update-ref --no-deref refs/heads/regularref $a && + format_command $type "symref-update refs/heads/regularref" "$a" "oid" "not-a-ref-oid" >stdin && + test_must_fail git update-ref --stdin $type err && + grep "fatal: symref-update refs/heads/regularref: invalid oid: not-a-ref-oid" err && + echo $(git rev-parse $a) >expect && + git rev-parse refs/heads/regularref >actual && + test_cmp expect actual + ' + + test_expect_success "stdin $type symref-update existing symref with zero old-oid" ' + test_when_finished "git symbolic-ref -d --no-recurse refs/heads/symref" && + git symbolic-ref refs/heads/symref refs/heads/target2 && + format_command $type "symref-update refs/heads/symref" "$a" "oid" "$Z" >stdin && + test_must_fail git update-ref --stdin $type err && + grep "fatal: cannot lock ref ${SQ}refs/heads/symref${SQ}: reference already exists" err && + echo refs/heads/target2 >expect && + git symbolic-ref refs/heads/symref >actual && + test_cmp expect actual + ' + + test_expect_success "stdin $type symref-update regular ref to symref (with deref)" ' + test_when_finished "git symbolic-ref -d refs/heads/symref" && + test_when_finished "git update-ref -d --no-deref refs/heads/symref2" && + git update-ref refs/heads/symref2 $a && + git symbolic-ref --no-recurse refs/heads/symref refs/heads/symref2 && + format_command $type "symref-update refs/heads/symref" "$a" >stdin && + git update-ref $type --stdin expect && + git symbolic-ref --no-recurse refs/heads/symref2 >actual && + test_cmp expect actual && + echo refs/heads/symref2 >expect && + git symbolic-ref --no-recurse refs/heads/symref >actual && + test_cmp expect actual && + test-tool ref-store main for-each-reflog-ent refs/heads/symref >actual && + grep "$(git rev-parse $a) $(git rev-parse $a)" actual + ' + + test_expect_success "stdin $type symref-update regular ref to symref" ' + test_when_finished "git symbolic-ref -d --no-recurse refs/heads/regularref" && + git update-ref --no-deref refs/heads/regularref $a && + format_command $type "symref-update refs/heads/regularref" "$a" >stdin && + git update-ref $type --stdin expect && + git symbolic-ref --no-recurse refs/heads/regularref >actual && + test_cmp expect actual && + test-tool ref-store main for-each-reflog-ent refs/heads/regularref >actual && + grep "$(git rev-parse $a) $(git rev-parse $a)" actual + ' + done test_done diff --git a/t/t1416-ref-transaction-hooks.sh b/t/t1416-ref-transaction-hooks.sh index ff77dcca6b..5a812ca3c0 100755 --- a/t/t1416-ref-transaction-hooks.sh +++ b/t/t1416-ref-transaction-hooks.sh @@ -163,6 +163,7 @@ test_expect_success 'hook gets all queued symref updates' ' git update-ref refs/heads/branch $POST_OID && git symbolic-ref refs/heads/symref refs/heads/main && git symbolic-ref refs/heads/symrefd refs/heads/main && + git symbolic-ref refs/heads/symrefu refs/heads/main && test_hook reference-transaction <<-\EOF && echo "$*" >>actual @@ -190,10 +191,12 @@ test_expect_success 'hook gets all queued symref updates' ' ref:refs/heads/main $ZERO_OID refs/heads/symref ref:refs/heads/main $ZERO_OID refs/heads/symrefd $ZERO_OID ref:refs/heads/main refs/heads/symrefc + ref:refs/heads/main ref:refs/heads/branch refs/heads/symrefu committed ref:refs/heads/main $ZERO_OID refs/heads/symref ref:refs/heads/main $ZERO_OID refs/heads/symrefd $ZERO_OID ref:refs/heads/main refs/heads/symrefc + ref:refs/heads/main ref:refs/heads/branch refs/heads/symrefu EOF git update-ref --no-deref --stdin <<-EOF && @@ -201,6 +204,7 @@ test_expect_success 'hook gets all queued symref updates' ' symref-verify refs/heads/symref refs/heads/main symref-delete refs/heads/symrefd refs/heads/main symref-create refs/heads/symrefc refs/heads/main + symref-update refs/heads/symrefu refs/heads/branch ref refs/heads/main prepare commit EOF