Revert "dir.c: don't exclude whole dir prematurely if neg pattern may match"
This reverts commit 57534ee77d22e725d971ee89c77dc6aad61c573f. The
feature added in that commit requires that patterns behave the same way
from anywhere. But some patterns can behave differently depending on
current "working" directory. The conditions to catch and avoid these
patterns are too loose. The untracked listing[1] and sparse-checkout
selection[2] can become incorrect as a result.
dir.c: don't exclude whole dir prematurely if neg pattern may match
If there is a pattern "!foo/bar", this patch makes it not exclude "foo"
right away. This gives us a chance to examine "foo" and re-include
"foo/bar".
In order for it to detect that the directory under examination should
not be excluded right away, in other words it is a parent directory of a
negative pattern, the "directory path" of the negative pattern must be
literal. Patterns like "!f?o/bar" can't stop "foo" from being excluded.
Basename matching (i.e. "no slashes in the pattern") or must-be-dir
matching (i.e. "trailing slash in the pattern") does not work well with
this. For example, if we descend in "foo" and are examining "foo/abc",
current code for "foo/" pattern will check if path "foo/abc", not "foo",
is a directory. The same problem with basename matching. These may need
big code reorg to make it work.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
dir.c: make last_exclude_matching_from_list() run til the end
The next patch adds some post processing to the result value before it's
returned to the caller. Keep all branches reach the end of the function,
so we can do it all in one place.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we show "branch@{0}", we format into a fixed-size
buffer using sprintf. This can overflow if you have long
branch names. We can fix it by using a temporary strbuf.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
read_info_alternates: handle paths larger than PATH_MAX
This function assumes that the relative_base path passed
into it is no larger than PATH_MAX, and writes into a
fixed-size buffer. However, this path may not have actually
come from the filesystem; for example, add_submodule_odb
generates a path using a strbuf and passes it in. This is
hard to trigger in practice, though, because the long
submodule directory would have to exist on disk before we
would try to open its info/alternates file.
We can easily avoid the bug, though, by simply creating the
filename on the heap.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we are loading a notes tree into our internal hash
table, we also collect any files that are clearly non-notes.
We format the name of the file into a PATH_MAX buffer, but
unlike true notes (which cannot be larger than a fanned-out
sha1 hash), these tree entries can be arbitrarily long,
overflowing our buffer.
We can fix this by switching to a strbuf. It doesn't even
cost us an extra allocation, as we can simply hand ownership
of the buffer over to the non-note struct.
This is of moderate security interest, as you might fetch
notes trees from an untrusted remote. However, we do not do
so by default, so you would have to manually fetch into the
notes namespace.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
verify_absent: allow filenames longer than PATH_MAX
When unpack-trees wants to know whether a path will
overwrite anything in the working tree, we use lstat() to
see if there is anything there. But if we are going to write
"foo/bar", we can't just lstat("foo/bar"); we need to look
for leading prefixes (e.g., "foo"). So we use the lstat cache
to find the length of the leading prefix, and copy the
filename up to that length into a temporary buffer (since
the original name is const, we cannot just stick a NUL in
it).
The copy we make goes into a PATH_MAX-sized buffer, which
will overflow if the prefix is longer than PATH_MAX. How
this happens is a little tricky, since in theory PATH_MAX is
the biggest path we will have read from the filesystem. But
this can happen if:
- the compiled-in PATH_MAX does not accurately reflect
what the filesystem is capable of
- the leading prefix is not _quite_ what is on disk; it
contains the next element from the name we are checking.
So if we want to write "aaa/bbb/ccc/ddd" and "aaa/bbb"
exists, the prefix of interest is "aaa/bbb/ccc". If
"aaa/bbb" approaches PATH_MAX, then "ccc" can overflow
it.
So this can be triggered, but it's hard to do. In
particular, you cannot just "git clone" a bogus repo. The
verify_absent checks happen before unpack-trees writes
anything to the filesystem, so there are never any leading
prefixes during the initial checkout, and the bug doesn't
trigger. And by definition, these files are larger than
PATH_MAX, so writing them will fail, and clone will
complain (though it may write a partial path, which will
cause a subsequent "git checkout" to hit the bug).
We can fix it by creating the temporary path on the heap.
The extra malloc overhead is not important, as we are
already making at least one stat() call (and probably more
for the prefix discovery).
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'jc/diff-no-index-d-f' into maint-2.3
The usual "git diff" when seeing a file turning into a directory
showed a patchset to remove the file and create all files in the
directory, but "git diff --no-index" simply refused to work. Also,
when asked to compare a file and a directory, imitate POSIX "diff"
and compare the file with the file with the same name in the
directory, instead of refusing to run.
* jc/diff-no-index-d-f:
diff-no-index: align D/F handling with that of normal Git
diff-no-index: DWIM "diff D F" into "diff D/F F"
Merge branch 'tb/connect-ipv6-parse-fix' into maint
An earlier update to the parser that disects a URL broke an
address, followed by a colon, followed by an empty string (instead
of the port number), e.g. ssh://example.com:/path/to/repo.
* tb/connect-ipv6-parse-fix:
connect.c: ignore extra colon after hostname
The "git push --signed" protocol extension did not limit what the
"nonce" that is a server-chosen string can contain or how long it
can be, which was unnecessarily lax. Limit both the length and the
alphabet to a reasonably small space that can still have enough
entropy.
* jc/push-cert:
push --signed: tighten what the receiving end can ask to sign
"diff-highlight" (in contrib/) used to show byte-by-byte
differences, which meant that multi-byte characters can be chopped
in the middle. It learned to pay attention to character boundaries
(assuming the UTF-8 payload).
* jk/colors:
diff-highlight: do not split multibyte characters
* jk/test-annoyances:
t5551: make EXPENSIVE test cheaper
t5541: move run_with_cmdline_limit to test-lib.sh
t: pass GIT_TRACE through Apache
t: redirect stderr GIT_TRACE to descriptor 4
t: translate SIGINT to an exit
The old wording was somehow implying that <start> and <end> were not
regular expressions. Also, the common case is to use a plain function
name here so <funcname> makes sense (the fact that it is a regular
expression is documented in line-range-format.txt).
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr> Signed-off-by: Junio C Hamano <gitster@pobox.com>
parse_date_basic(): let the system handle DST conversion
The function parses the input to compute the broken-down time in
"struct tm", and the GMT timezone offset. If the timezone offset
does not exist in the input, the broken-down time is turned into the
number of seconds since epoch both in the current timezone and in
GMT and the offset is computed as their difference.
However, we forgot to make sure tm.tm_isdst is set to -1 (i.e. let
the system figure out if DST is in effect in the current timezone
when turning the broken-down time to the number of seconds since
epoch); it is done so at the beginning of the function, but a call
to match_digit() in the function can lead to a call to gmtime_r() to
clobber the field.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Diagnosed-by: Eric Sunshine <sunshine@sunshineco.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
parse_date_basic(): return early when given a bogus timestamp
When the input does not have GMT timezone offset, the code computes
it by computing the local and GMT time for the given timestamp. But
there is no point doing so if the given timestamp is known to be a
bogus one.
Changed inaccurate count of "rough rules" from three to the more
generic 'a few'.
Signed-off-by: Julian Gindi <juliangindi@gmail.com> Reviewed-by: Eric Sunshine <sunshine@sunshineco.com> Reviewed-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Ignore an extra ':' at the end of the hostname in URL's like
"ssh://example.com:/path/to/repo"
The colon is meant to separate a port number from the hostname.
If the port is empty, the colon should be ignored, see RFC 3986.
It had been working for URLs with ssh:// scheme, but was unintentionally
broken in 86ceb3, "allow ssh://user@[2001:db8::1]/repo.git"
Reported-by: Reid Woodbury Jr. <reidw@rawsound.com> Signed-off-by: Torsten Bögershausen <tboegi@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
When the input is UTF-8 and Perl is operating on bytes instead of
characters, a diff that changes one multibyte character to another
that shares an initial byte sequence will result in a broken diff
display as the common byte sequence prefix will be separated from
the rest of the bytes in the multibyte character.
For example, if a single line contains only the unicode character
U+C9C4 (encoded as UTF-8 0xEC, 0xA7, 0x84) and that line is then
changed to the unicode character U+C9C0 (encoded as UTF-8 0xEC,
0xA7, 0x80), when operating on bytes diff-highlight will show only
the single byte change from 0x84 to 0x80 thus creating invalid UTF-8
and a broken diff display.
Fix this by putting Perl into character mode when splitting the line
and then back into byte mode after the split is finished.
The utf8::xxx functions require Perl 5.8 so we require that as well.
Also, since we are mucking with code in the split_line function, we
change a '*' quantifier to a '+' quantifier when matching the $COLOR
expression which has the side effect of speeding everything up while
eliminating useless '' elements in the returned array.
Reported-by: Yi EungJun <semtlenori@gmail.com> Signed-off-by: Kyle J. McKay <mackyle@gmail.com> Acked-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
push --signed: tighten what the receiving end can ask to sign
Instead of blindly trusting the receiving side to give us a sensible
nonce to sign, limit the length (max 256 bytes) and the alphabet
(alnum and a few selected punctuations, enough to encode in base64)
that can be used in nonce.
howto: document more tools for recovery corruption
Long ago, I documented a corruption recovery I did and gave
some C code that I used to help find a flipped bit. I had
to fix a similar case recently, and I ended up writing a few
more tools. I hope nobody ever has to use these, but it
does not hurt to share them, just in case.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merges with an absurd number of parents are still a bad idea because
they do not render well in tools like gitk, but if they are present
in the repository being imported into git then there's no need to
avoid reproducing them faithfully.
In olden times, before v1.6.0-rc0~194 (2008-06-27), git commit-tree
and higher-level tools built on top of it were limited to writing 16
parents for a commit. Nowadays normal git operations are happy to
write more parents when asked, so the motivation for this note in the
fast-import documentation is gone and we can remove it.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
gitweb.conf.txt: say "build-time", not "built-time"
"build-time" is used everywhere else.
Signed-off-by: Jérôme Zago <git-patch@agt-the-walker.net> Reviewed-by: Jakub Narębski <jnareb@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
In b3256eb (standardize and improve lookup rules for external local
repos), enter_repo() was modified to use a different precedence
ordering of suffixes for DWIM of the repository path, and to ensure
that the repository path is actually valid instead of just testing
for existence.
However, the documentation was not modified to reflect these
changes. Fix the documentation to match the code.
Documentation contributed by Jeff King.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Paul Tan <pyokagan@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
cherry-pick: fix docs describing handling of empty commits
Commit b27cfb0 (git-cherry-pick: Add keep-redundant-commits
option, 2012-04-20), added the --keep-redundant-commits
option, and switched the default behavior (without that
option) to silently ignore empty commits. Later, the second
half of that commit was reverted in ac2b0e8 (cherry-pick:
regression fix for empty commits, 2012-05-29), but the
documentation added for --keep-redundant-commits was never
updated to match. Let's do so now.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
docs: clarify what git-rebase's "-p" / "--preserve-merges" does
Ignoring a merge can be read as ignoring the changes a merge commit
introduces altogether, as if the entire side branch the merge commit
merged was removed from the history. But that is not what happens
if "-p" is not specified. What happens is that the individual
commits a merge commit introduces are replayed in order, and only
any possible merge conflict resolutions or manual amendments to the
merge commit are ignored.
Get this straight in the docs.
Also, do not say that merge commits are *tried* to be recreated. As that is
true almost everywhere it is better left unsaid.
Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
parse-options.h: OPTION_{BIT,SET_INT} do not store pointer to defval
When 20d1c652 (parse-options: remove unused OPT_SET_PTR, 2014-03-30)
removed OPT_SET_PTR, the comment in the header that describes what
the option did to defval field was left behind by mistake. Remove
it.
Signed-off-by: Ivan Ukhov <ivan.ukhov@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
An failure early in the "git clone" that started creating the
working tree and repository could have resulted in some directories
and files left without getting cleaned up.
* jk/cleanup-failed-clone:
clone: drop period from end of die_errno message
clone: initialize atexit cleanup handler earlier
"git fetch" that fetches a commit using the allow-tip-sha1-in-want
extension could have failed to fetch all the requested refs.
* jk/fetch-pack:
fetch-pack: remove dead assignment to ref->new_sha1
fetch_refs_via_pack: free extra copy of refs
filter_ref: make a copy of extra "sought" entries
filter_ref: avoid overwriting ref->old_sha1 with garbage
Merge branch 'tg/fix-check-order-with-split-index' into maint
The split-index mode introduced at v2.3.0-rc0~41 was broken in the
codepath to protect us against a broken reimplementation of Git
that writes an invalid index with duplicated index entries, etc.
* tg/fix-check-order-with-split-index:
read-cache: fix reading of split index
Merge branch 'jk/prune-with-corrupt-refs' into maint
"git prune" used to largely ignore broken refs when deciding which
objects are still being used, which could spread an existing small
damage and make it a larger one.
* jk/prune-with-corrupt-refs:
refs.c: drop curate_packed_refs
repack: turn on "ref paranoia" when doing a destructive repack
prune: turn on ref_paranoia flag
refs: introduce a "ref paranoia" flag
t5312: test object deletion code paths in a corrupted repository
Merge branch 'js/completion-ctags-pattern-substitution-fix' into maint
The code that reads from the ctags file in the completion script
(in contrib/) did not spell ${param/pattern/string} substitution
correctly, which happened to work with bash but not with zsh.
* js/completion-ctags-pattern-substitution-fix:
contrib/completion: escape the forward slash in __git_match_ctag
diff-no-index: align D/F handling with that of normal Git
When a commit changes a path P that used to be a file to a directory
and creates a new path P/X in it, "git show" would say that file P
was removed and file P/X was created for such a commit.
However, if we compare two directories, D1 and D2, where D1 has a
file D1/P in it and D2 has a directory D2/P under which there is a
file D2/P/X, and ask "git diff --no-index D1 D2" to show their
differences, we simply get a refusal "file/directory conflict".
Surely, that may be what GNU diff does, but we can do better and it
is easy to do so.
docs: clarify "preserve" option wording for git-pull
The "also" sounds as if "preserve" does a rebase as an additional
step that "true" would not do, but that is not the case. Clarify
this by omitting "also", and rewording the sentence a bit.
Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The help text for the --force-with-lease option to git-push
does not parse cleanly. Clean up the wording and syntax to
be more sensible. Also remove redundant information in the
"--force-with-lease alone" description.
Signed-off-by: Phil Hord <hordp@cisco.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git diff --no-index" was supposed to be a poor-man's approach to
allow using Git diff goodies outside of a Git repository, without
having to patch mainstream diff implementations.
Unlike a POSIX diff that treats "diff D F" (or "diff F D") as a
request to compare D/F and F (or F and D/F) when D is a directory
and F is a file, however, we did not accept such a command line and
instead barfed with "file/directory conflict".
Imitate what POSIX diff does and append the basename of the file
after the name of the directory before comparing.
The expected call sequence is for the caller to use match_pathspec()
repeatedly on a set of pathspecs, accumulating the "hits" in a
separate array, and then call this function to diagnose a pathspec
that never matched anything, as that can indicate a typo from the
command line, e.g. "git commit Maekfile".
Many builtin commands use this function from builtin/ls-files.c,
which is not a very healthy arrangement. ls-files might have been
the first command to feel the need for such a helper, but the need
is shared by everybody who uses the "match and then report" pattern.
Move it to dir.c where match_pathspec() is defined.
At the first look, a user may think the default version is "23". Even
with UNIX background, there's no reference anywhere close that may
indicate this is glob or regex.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'jc/decorate-leaky-separator-color' into maint
"git log --decorate" did not reset colors correctly around the
branch names.
* jc/decorate-leaky-separator-color:
log --decorate: do not leak "commit" color into the next item
Documentation/config.txt: simplify boolean description in the syntax section
Documentation/config.txt: describe 'color' value type in the "Values" section
Documentation/config.txt: have a separate "Values" section
Documentation/config.txt: describe the structure first and then meaning
Documentation/config.txt: explain multi-valued variables once
Documentation/config.txt: avoid unnecessary negation
Merge branch 'km/imap-send-libcurl-options' into maint
"git imap-send" learned to optionally talk with an IMAP server via
libcURL; because there is no other option when Git is built with
NO_OPENSSL option, use that codepath by default under such
configuration.
* km/imap-send-libcurl-options:
imap-send: use cURL automatically when NO_OPENSSL defined
"git rebase -i" recently started to include the number of
commits in the insn sheet to be processed, but on a platform
that prepends leading whitespaces to "wc -l" output, the numbers
are shown with extra whitespaces that aren't necessary.
Merge branch 'tb/connect-ipv6-parse-fix' into maint
We did not parse username followed by literal IPv6 address in SSH
transport URLs, e.g. ssh://user@[2001:db8::1]:22/repo.git
correctly.
* tb/connect-ipv6-parse-fix:
t5500: show user name and host in diag-url
t5601: add more test cases for IPV6
connect.c: allow ssh://user@[2001:db8::1]/repo.git
completion: use __gitcomp_nl() for completing refs
We do that almost everywhere, because it's faster for large number of
refs, see a31e62629 (completion: optimize refs completion, 2011-10-15).
These were the last two places where we still used __gitcomp() for
completing refs.
Signed-off-by: SZEDER Gábor <szeder@ira.uka.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The split index extension uses ewah bitmaps to mark index entries as
deleted, instead of removing them from the index directly. This can
result in an on-disk index, in which entries of stage #0 and higher
stages appear, which are removed later when the index bases are merged.
15999d0 read_index_from(): catch out of order entries when reading an
index file introduces a check which checks if the entries are in order
after each index entry is read in do_read_index. This check may however
fail when a split index is read.
Fix this by moving checking the index after we know there is no split
index or after the split index bases are successfully merged instead.
Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we delete a ref, we have to rewrite the entire
packed-refs file. We take this opportunity to "curate" the
packed-refs file and drop any entries that are crufty or
broken.
Dropping broken entries (e.g., with bogus names, or ones
that point to missing objects) is actively a bad idea, as it
means that we lose any notion that the data was there in the
first place. Aside from the general hackiness that we might
lose any information about ref "foo" while deleting an
unrelated ref "bar", this may seriously hamper any attempts
by the user at recovering from the corruption in "foo".
They will lose the sha1 and name of "foo"; the exact pointer
may still be useful even if they recover missing objects
from a different copy of the repository. But worse, once the
ref is gone, there is no trace of the corruption. A
follow-up "git prune" may delete objects, even though it
would otherwise bail when seeing corruption.
We could just drop the "broken" bits from
curate_packed_refs, and continue to drop the "crufty" bits:
refs whose loose counterpart exists in the filesystem. This
is not wrong to do, and it does have the advantage that we
may write out a slightly smaller packed-refs file. But it
has two disadvantages:
1. It is a potential source of races or mistakes with
respect to these refs that are otherwise unrelated to
the operation. To my knowledge, there aren't any active
problems in this area, but it seems like an unnecessary
risk.
2. We have to spend time looking up the matching loose
refs for every item in the packed-refs file. If you
have a large number of packed refs that do not change,
that outweighs the benefit from writing out a smaller
packed-refs file (it doesn't get smaller, and you do a
bunch of directory traversal to find that out).
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
repack: turn on "ref paranoia" when doing a destructive repack
If we are repacking with "-ad", we will drop any unreachable
objects. Likewise, using "-Ad --unpack-unreachable=<time>"
will drop any old, unreachable objects. In these cases, we
want to make sure the reachability we compute with "--all"
is complete. We can do this by passing GIT_REF_PARANOIA=1 in
the environment to pack-objects.
Note that "-Ad" is safe already, because it only loosens
unreachable objects. It is up to "git prune" to avoid
deleting them.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Prune should know about broken objects at the tips of refs,
so that we can feed them to our traversal rather than
ignoring them. It's better for us to abort the operation on
the broken object than it is to start deleting objects with
an incomplete view of the reachability namespace.
Note that for missing objects, aborting is the best we can
do. For a badly-named ref, we technically could use its sha1
as a reachability tip. However, the iteration code just
feeds us a null sha1, so there would be a reasonable amount
of code involved to pass down our wishes. It's not really
worth trying to do better, because this is a case that
should happen extremely rarely, and the message we provide:
fatal: unable to parse object: refs/heads/bogus:name
is probably enough to point the user in the right direction.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Most operations that iterate over refs are happy to ignore
broken cruft. However, some operations should be performed
with knowledge of these broken refs, because it is better
for the operation to choke on a missing object than it is to
silently pretend that the ref did not exist (e.g., if we are
computing the set of reachable tips in order to prune
objects).
These processes could just call for_each_rawref, except that
ref iteration is often hidden behind other interfaces. For
instance, for a destructive "repack -ad", we would have to
inform "pack-objects" that we are destructive, and then it
would in turn have to tell the revision code that our
"--all" should include broken refs.
It's much simpler to just set a global for "dangerous"
operations that includes broken refs in all iterations.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
t5312: test object deletion code paths in a corrupted repository
When we are doing a destructive operation like "git prune",
we want to be extra careful that the set of reachable tips
we compute is valid. If there is any corruption or oddity,
we are better off aborting the operation and letting the
user figure things out rather than plowing ahead and
possibly deleting some data that cannot be recovered.
The tests here include:
1. Pruning objects mentioned only be refs with invalid
names. This used to abort prior to d0f810f (refs.c:
allow listing and deleting badly named refs,
2014-09-03), but since then we silently ignore the tip.
Likewise, we test repacking that can drop objects
(either "-ad", which drops anything unreachable,
or "-Ad --unpack-unreachable=<time>", which tries to
optimize out a loose object write that would be
directly pruned).
2. Pruning objects when some refs point to missing
objects. We don't know whether any dangling objects
would have been reachable from the missing objects. We
are better to keep them around, as they are better than
nothing for helping the user recover history.
3. Packed refs that point to missing objects can sometimes
be dropped. By itself, this is more of an annoyance
(you do not have the object anyway; even if you can
recover it from elsewhere, all you are losing is a
placeholder for your state at the time of corruption).
But coupled with (2), if we drop the ref and then go
on to prune, we may lose unrecoverable objects.
Note that we use test_might_fail for some of the operations.
In some cases, it would be appropriate to abort the
operation, and in others, it might be acceptable to continue
but taking the information into account. The tests don't
care either way, and check only for data loss.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The different index versions have different sha-1 checksums. Those
checksums are checked in t1700, which makes it fail when the test suite
is run with TEST_GIT_INDEX_VERSION=4. Fix it.
Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
fetch-pack: remove dead assignment to ref->new_sha1
In everything_local(), we used to assign the current ref's value
found in ref->old_sha1 to ref->new_sha1 when we already have all the
necessary objects to complete the history leading to that
commit. This copying was broken at 49bb805e (Do not ask for
objects known to be complete., 2005-10-19) and ever since we
instead stuffed a random bytes in ref->new_sha1 here. No
code complained or failed due to this breakage.
It turns out that no code path that comes after this
assignment even looks at ref->new_sha1 at all.
- The only caller of everything_local(), do_fetch_pack(),
returns this list of refs, whose element has bogus
new_sha1 values, to its caller. It does not look at the
elements itself, but does pass them to find_common, which
looks only at the name and old_sha1 fields.
- The only caller of do_fetch_pack(), fetch_pack(), returns this
list to its caller. It does not look at the elements nor act on
them.
- One of the two callers of fetch_pack() is cmd_fetch_pack(), the
top-level that implements "git fetch-pack". The only thing it
looks at in the elements of the returned ref list is the old_sha1
and name fields.
- The other caller of fetch_pack() is fetch_refs_via_pack() in the
transport layer, which is a helper that implements "git fetch".
It only cares about whether the returned list is empty (i.e.
failed to fetch anything).
Just drop the bogus assignment, that is not even necessary. The
remote-tracking refs are updated based on a different list and not
using the ref list being manipulated by this code path; the caller
do_fetch_pack() created a copy of that real ref list and passed the
copy down to this function, and modifying the elements here does not
affect anything.
Noticed-by: Kyle J. McKay <mackyle@gmail.com> Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
When fetch_refs_via_pack calls fetch_pack(), we pass a
list of refs to fetch, and the function returns either a
copy of that list, with the fetched items filled in, or
NULL. We check the return value to see whether the fetch was
successful, but do not otherwise look at the copy, and
simply leak it at the end of the function.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
If the server supports allow_tip_sha1_in_want, we add any
unmatched raw-sha1 entries in our "sought" list of refs to
the list of refs we will ask the other side for. We do so by
inserting the original "struct ref" directly into our list,
rather than making a copy. This has several problems.
The most minor problem is that one cannot ever free the
resulting list; it contains structs that are copies of the
remote refs (made earlier by fetch_pack) along with sought
refs that are referenced elsewhere.
But more importantly that we set the ref->next pointer to
NULL, chopping off the remainder of any existing list that
the ref was a part of. We get the set of "sought" refs in
an array rather than a linked list, but that array is often
in turn generated from a list. The test modification in
t5516 demonstrates this. Rather than fetching just an exact
sha1, we fetch that sha1 plus another ref:
- we build a linked list of refs to fetch when do_fetch
calls get_ref_map; the exact sha1 is first, followed by
the named ref ("refs/heads/extra" in this case).
- we pass that linked list to transport_fetch_ref, which
squashes it into an array of pointers
- that array goes to fetch_pack, which calls filter_ref.
There we generate the want list from a mix of what the
remote side has advertised, and the "sought" entry for
the exact sha1. We set the sought entry's "next" pointer
to NULL.
- after we return from transport_fetch_refs, we then try
to update the refs by following the linked list. But our
list is now truncated, and we do not update
refs/heads/extra at all.
We can fix this by making a copy of the ref. There's nothing
that fetch_pack does to it that must be reflected in the
original "sought" list (and indeed, if that were the case we
would have a serious bug, because it is only exact-sha1
entries which are treated this way).
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
filter_ref: avoid overwriting ref->old_sha1 with garbage
If the server supports allow_tip_sha1_in_want, then
fetch-pack's filter_refs function tries to check whether a
ref is a request for a straight sha1 by running:
if (get_sha1_hex(ref->name, ref->old_sha1))
...
I.e., we are using get_sha1_hex to ask "is this ref name a
sha1?". If it is true, then the contents of ref->old_sha1
will end up unchanged. But if it is false, then get_sha1_hex
makes no guarantees about what it has written. With a ref
name like "abcdefoo", we would overwrite 3 bytes of
ref->old_sha1 before realizing that it was not a sha1.
This is likely not a problem in practice, as anything in
refs->name (besides a sha1) will start with "refs/", meaning
that we would notice on the first character that there is a
problem. Still, we are making assumptions about the state
left in the output when get_sha1_hex returns an error (e.g.,
it could start from the end of the string, or error check
the values only once they were placed in the output). It's
better to be defensive.
We could just check that we have exactly 40 characters of
sha1. But let's be even more careful and make sure that we
have a 40-char hex refname that matches what is in old_sha1.
This is perhaps overly defensive, but spells out our
assumptions clearly.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
If clone fails, we generally try to clean up any directories
we've created. We do this by installing an atexit handler,
so that we don't have to manually trigger cleanup. However,
since we install this after touching the filesystem, any
errors between our initial mkdir() and our atexit() call
will result in us leaving a crufty directory around.
We can fix this by moving our atexit() call earlier. It's OK
to do it before the junk_work_tree variable is set, because
remove_junk makes sure the variable is initialized. This
means we "activate" the handler by assigning to the
junk_work_tree variable, which we now bump down to just
after we call mkdir(). We probably do not want to do it
before, because a plausible reason for mkdir() to fail is
EEXIST (i.e., we are racing with another "git init"), and we
would not want to remove their work.
OTOH, this is probably not that big a deal; we will allow
cloning into an empty directory (and skip the mkdir), which
is already racy (i.e., one clone may see the other's empty
dir and start writing into it). Still, it does not hurt to
err on the side of caution here.
Note that writing into junk_work_tree and junk_git_dir after
installing the handler is also technically racy, as we call
our handler on an async signal. Depending on the platform,
we could see a sheared write to the variables. Traditionally
we have not worried about this, and indeed we already do
this later in the function. If we want to address that, it
can come as a separate topic.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>