git-commit-vandalism/t/t5527-fetch-odd-refs.sh

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fetch-pack: match refs exactly When we are determining the list of refs to fetch via fetch-pack, we have two sets of refs to compare: those on the remote side, and a "match" list of things we want to fetch. We iterate through the remote refs alphabetically, seeing if each one is wanted by the "match" list. Since def88e9 (Commit first cut at "git-fetch-pack", 2005-07-04), we have used the "path_match" function to do a suffix match, where a remote ref is considered wanted if any of the "match" elements is a suffix of the remote refname. This enables callers of fetch-pack to specify unqualified refs and have them matched up with remote refs (e.g., ask for "A" and get remote's "refs/heads/A"). However, if you provide a fully qualified ref, then there are corner cases where we provide the wrong answer. For example, given a remote with two refs: refs/foo/refs/heads/master refs/heads/master asking for "refs/heads/master" will first match "refs/foo/refs/heads/master" by the suffix rule, and we will erroneously fetch it instead of refs/heads/master. As it turns out, all callers of fetch_pack do provide fully-qualified refs for the match list. There are two ways fetch_pack can get match lists: 1. Through the transport code (i.e., via git-fetch) 2. On the command-line of git-fetch-pack In the first case, we will always be providing the names of fully-qualified refs from "struct ref" objects. We will have pre-matched those ref objects already (since we have to handle more advanced matching, like wildcard refspecs), and are just providing a list of the refs whose objects we need. In the second case, users could in theory be providing non-qualified refs on the command-line. However, the fetch-pack documentation claims that refs should be fully qualified (and has always done so since it was written in 2005). Let's change this path_match call to simply check for string equality, matching what the callers of fetch_pack are expecting. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-12-13 01:48:08 +01:00
#!/bin/sh
test_description='test fetching of oddly-named refs'
. ./test-lib.sh
# afterwards we will have:
# HEAD - two
# refs/for/refs/heads/master - one
# refs/heads/master - three
test_expect_success 'setup repo with odd suffix ref' '
echo content >file &&
git add . &&
git commit -m one &&
git update-ref refs/for/refs/heads/master HEAD &&
echo content >>file &&
git commit -a -m two &&
echo content >>file &&
git commit -a -m three &&
git checkout HEAD^
'
test_expect_success 'suffix ref is ignored during fetch' '
git clone --bare file://"$PWD" suffix &&
echo three >expect &&
git --git-dir=suffix log -1 --format=%s refs/heads/master >actual &&
test_cmp expect actual
'
pkt-line: allow writing of LARGE_PACKET_MAX buffers When we send out pkt-lines with refnames, we use a static 1000-byte buffer. This means that the maximum size of a ref over the git protocol is around 950 bytes (the exact size depends on the protocol line being written, but figure on a sha1 plus some boilerplate). This is enough for any sane workflow, but occasionally odd things happen (e.g., a bug may create a ref "foo/foo/foo/..." accidentally). With the current code, you cannot even use "push" to delete such a ref from a remote. Let's switch to using a strbuf, with a hard-limit of LARGE_PACKET_MAX (which is specified by the protocol). This matches the size of the readers, as of 74543a0 (pkt-line: provide a LARGE_PACKET_MAX static buffer, 2013-02-20). Versions of git older than that will complain about our large packets, but it's really no worse than the current behavior. Right now the sender barfs with "impossibly long line" trying to send the packet, and afterwards the reader will barf with "protocol error: bad line length %d", which is arguably better anyway. Note that we're not really _solving_ the problem here, but just bumping the limits. In theory, the length of a ref is unbounded, and pkt-line can only represent sizes up to 65531 bytes. So we are just bumping the limit, not removing it. But hopefully 64K should be enough for anyone. As a bonus, by using a strbuf for the formatting we can eliminate an unnecessary copy in format_buf_write. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-10 10:47:02 +01:00
test_expect_success 'try to create repo with absurdly long refname' '
ref240=$ZERO_OID/$ZERO_OID/$ZERO_OID/$ZERO_OID/$ZERO_OID/$ZERO_OID &&
pkt-line: allow writing of LARGE_PACKET_MAX buffers When we send out pkt-lines with refnames, we use a static 1000-byte buffer. This means that the maximum size of a ref over the git protocol is around 950 bytes (the exact size depends on the protocol line being written, but figure on a sha1 plus some boilerplate). This is enough for any sane workflow, but occasionally odd things happen (e.g., a bug may create a ref "foo/foo/foo/..." accidentally). With the current code, you cannot even use "push" to delete such a ref from a remote. Let's switch to using a strbuf, with a hard-limit of LARGE_PACKET_MAX (which is specified by the protocol). This matches the size of the readers, as of 74543a0 (pkt-line: provide a LARGE_PACKET_MAX static buffer, 2013-02-20). Versions of git older than that will complain about our large packets, but it's really no worse than the current behavior. Right now the sender barfs with "impossibly long line" trying to send the packet, and afterwards the reader will barf with "protocol error: bad line length %d", which is arguably better anyway. Note that we're not really _solving_ the problem here, but just bumping the limits. In theory, the length of a ref is unbounded, and pkt-line can only represent sizes up to 65531 bytes. So we are just bumping the limit, not removing it. But hopefully 64K should be enough for anyone. As a bonus, by using a strbuf for the formatting we can eliminate an unnecessary copy in format_buf_write. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-10 10:47:02 +01:00
ref1440=$ref240/$ref240/$ref240/$ref240/$ref240/$ref240 &&
git init long &&
(
cd long &&
test_commit long &&
test_commit master
) &&
if git -C long update-ref refs/heads/$ref1440 long; then
test_set_prereq LONG_REF
else
echo >&2 "long refs not supported"
fi
'
test_expect_success LONG_REF 'fetch handles extremely long refname' '
git fetch long refs/heads/*:refs/remotes/long/* &&
cat >expect <<-\EOF &&
long
master
EOF
git for-each-ref --format="%(subject)" refs/remotes/long >actual &&
test_cmp expect actual
'
test_expect_success LONG_REF 'push handles extremely long refname' '
git push long :refs/heads/$ref1440 &&
git -C long for-each-ref --format="%(subject)" refs/heads >actual &&
echo master >expect &&
test_cmp expect actual
'
fetch-pack: match refs exactly When we are determining the list of refs to fetch via fetch-pack, we have two sets of refs to compare: those on the remote side, and a "match" list of things we want to fetch. We iterate through the remote refs alphabetically, seeing if each one is wanted by the "match" list. Since def88e9 (Commit first cut at "git-fetch-pack", 2005-07-04), we have used the "path_match" function to do a suffix match, where a remote ref is considered wanted if any of the "match" elements is a suffix of the remote refname. This enables callers of fetch-pack to specify unqualified refs and have them matched up with remote refs (e.g., ask for "A" and get remote's "refs/heads/A"). However, if you provide a fully qualified ref, then there are corner cases where we provide the wrong answer. For example, given a remote with two refs: refs/foo/refs/heads/master refs/heads/master asking for "refs/heads/master" will first match "refs/foo/refs/heads/master" by the suffix rule, and we will erroneously fetch it instead of refs/heads/master. As it turns out, all callers of fetch_pack do provide fully-qualified refs for the match list. There are two ways fetch_pack can get match lists: 1. Through the transport code (i.e., via git-fetch) 2. On the command-line of git-fetch-pack In the first case, we will always be providing the names of fully-qualified refs from "struct ref" objects. We will have pre-matched those ref objects already (since we have to handle more advanced matching, like wildcard refspecs), and are just providing a list of the refs whose objects we need. In the second case, users could in theory be providing non-qualified refs on the command-line. However, the fetch-pack documentation claims that refs should be fully qualified (and has always done so since it was written in 2005). Let's change this path_match call to simply check for string equality, matching what the callers of fetch_pack are expecting. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-12-13 01:48:08 +01:00
test_done