Particularly when calling Git from applications, such as Visual Studio's
Team Explorer, it is important that stdin/stdout/stderr are closed
properly. However, when spawning processes on Windows, those handles
must be marked as inheritable if we want to use them, but that flag is a
global flag and may very well be used by other spawned processes which
then do not know to close those handles.
Let's introduce a set of environment variables (GIT_REDIRECT_STDIN and
friends) that specify paths to files, or even better, named pipes (which
are similar to Unix sockets) and that are used by the spawned Git
process. This helps work around above-mentioned issue: those named
pipes will be opened in a non-inheritable way upon startup, and no
handles are passed around (and therefore no inherited handles need to be
closed by any spawned child).
This feature shipped with Git for Windows (marked as experimental) since
v2.11.0(2), so it has seen some serious testing in the meantime.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A possible oom error is now caught as a fatal error, instead of
continuing and dereferencing NULL.
* ao/path-use-xmalloc:
path.c: use xmalloc() in add_to_trie()
The descriptions of the options '--parents', '--children' and
'--graph' say "see 'History Simplification' below", although the
referred section is in fact above the description of these options.
Send readers in the right direction by saying "above" instead of
"below".
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Transactions to update multiple references that involves a deletion
was quite broken in an error codepath and did not abort everything
correctly.
* mh/ref-locking-fix:
files_transaction_prepare(): fix handling of ref lock failure
t1404: add a bunch of tests of D/F conflicts
Add usage of xmalloc() instead of malloc() in add_to_trie() as xmalloc wraps
and checks memory allocation result.
Signed-off-by: Andrey Okoshkin <a.okoshkin@samsung.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since dc39e09942 (files_ref_store: use a transaction to update packed
refs, 2017-09-08), failure to lock a reference has been handled
incorrectly by `files_transaction_prepare()`. If
`lock_ref_for_update()` fails in the lock-acquisition loop of that
function, it sets `ret` then breaks out of that loop. Prior to
dc39e09942, that was OK, because the only thing following the loop was
the cleanup code. But dc39e09942 added another blurb of code between
the loop and the cleanup. That blurb sometimes resets `ret` to zero,
making the cleanup code think that the locking was successful.
Specifically, whenever
* One or more reference deletions have been processed successfully in
the lock-acquisition loop. (Processing the first such reference
causes a packed-ref transaction to be initialized.)
* Then `lock_ref_for_update()` fails for a subsequent reference. Such
a failure can happen for a number of reasons, such as the old SHA-1
not being correct, lock contention, etc. This causes a `break` out
of the lock-acquisition loop.
* The `packed-refs` lock is acquired successfully and
`ref_transaction_prepare()` succeeds for the packed-ref transaction.
This has the effect of resetting `ret` back to 0, and making the
cleanup code think that lock acquisition was successful.
In that case, any reference updates that were processed prior to
breaking out of the loop would be carried out (loose and packed), but
the reference that couldn't be locked and any subsequent references
would silently be ignored.
This can easily cause data loss if, for example, the user was trying
to push a new name for an existing branch while deleting the old name.
After the push, the branch could be left unreachable, and could even
subsequently be garbage-collected.
This problem was noticed in the context of deleting one reference and
creating another in a single transaction, when the two references D/F
conflict with each other, like
git update-ref --stdin <<EOF
delete refs/foo
create refs/foo/bar HEAD
EOF
This triggers the above bug because the deletion is processed
successfully for `refs/foo`, then the D/F conflict causes
`lock_ref_for_update()` to fail when `refs/foo/bar` is processed. In
this case the transaction *should* fail, but instead it causes
`refs/foo` to be deleted without creating `refs/foo`. This could
easily result in data loss.
The fix is simple: instead of just breaking out of the loop, jump
directly to the cleanup code. This fixes some tests in t1404 that were
added in the previous commit.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It is currently not allowed, in a single transaction, to add one
reference and delete another reference if the two reference names D/F
conflict with each other (e.g., like `refs/foo/bar` and `refs/foo`).
The reason is that the code would need to take locks
$GIT_DIR/refs/foo.lock
$GIT_DIR/refs/foo/bar.lock
But the latter lock couldn't coexist with the loose reference file
$GIT_DIR/refs/foo
, because `$GIT_DIR/refs/foo` cannot be both a directory and a file at
the same time (hence the name "D/F conflict).
Add a bunch of tests that we cleanly reject such transactions.
In fact, many of the new tests currently fail. They will be fixed in
the next commit along with an explanation.
Reported-by: Jeff King <peff@peff.net>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A regression fix for 2.11 that made the code to read the list of
alternate object stores overrun the end of the string.
* jk/info-alternates-fix:
read_info_alternates: warn on non-trivial errors
read_info_alternates: read contents into strbuf
"git fetch <there> <src>:<dst>" allows an object name on the <src>
side when the other side accepts such a request since Git v2.5, but
the documentation was left stale.
* jc/fetch-refspec-doc-update:
fetch doc: src side of refspec could be full SHA-1
Many codepaths did not diagnose write failures correctly when disks
go full, due to their misuse of write_in_full() helper function,
which have been corrected.
* jk/write-in-full-fix:
read_pack_header: handle signed/unsigned comparison in read result
config: flip return value of store_write_*()
notes-merge: use ssize_t for write_in_full() return value
pkt-line: check write_in_full() errors against "< 0"
convert less-trivial versions of "write_in_full() != len"
avoid "write_in_full(fd, buf, len) != len" pattern
get-tar-commit-id: check write_in_full() return against 0
config: avoid "write_in_full(fd, buf, len) < len" pattern
The scripts to drive TravisCI has been reorganized and then an
optimization to avoid spending cycles on a branch whose tip is
tagged has been implemented.
* ls/travis-scriptify:
travis-ci: fix "skip_branch_tip_with_tag()" string comparison
travis: dedent a few scripts that are indented overly deeply
travis-ci: skip a branch build if equal tag is present
travis-ci: move Travis CI code into dedicated scripts
The checkpoint command "git fast-import" did not flush updates to
refs and marks unless at least one object was created since the
last checkpoint, which has been corrected, as these things can
happen without any new object getting created.
* er/fast-import-dump-refs-on-checkpoint:
fast-import: checkpoint: dump branches/tags/marks even if object_count==0
"git fast-export" with -M/-C option issued "copy" instruction on a
path that is simultaneously modified, which was incorrect.
* jt/fast-export-copy-modify-fix:
fast-export: do not copy from modified file
"git branch -M a b" while on a branch that is completely unrelated
to either branch a or branch b misbehaved when multiple worktree
was in use. This has been fixed.
* nd/worktree-kill-parse-ref:
branch: fix branch renaming not updating HEADs correctly
Update the documentation for "git filter-branch" so that the filter
options are listed in the same order as they are applied, as
described in an earlier part of the doc.
* dg/filter-branch-filter-order-doc:
doc: list filter-branch subdirectory-filter first
"git fetch <there> <src>:<dst>" allows an object name on the <src>
side when the other side accepts such a request since Git v2.5, but
the documentation was left stale.
* jc/fetch-refspec-doc-update:
fetch doc: src side of refspec could be full SHA-1
Change the word "bla" to "section.variable"; "bla" is a placeholder
for a variable name but it wasn't clear for everyone.
While we're here, also reformat this sample command line to use
monospace instead of italics, to better match the rest of the file.
Use a space instead of a dash in "git config", as is common in the
rest of Git's documentation.
Reported-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: MOY Matthieu <matthieu.moy@univ-lyon1.fr>
Signed-off-by: Daniel Bensoussan <daniel.bensoussan--bohm@etu.univ-lyon1.fr>
Signed-off-by: Timothee Albertin <timothee.albertin@etu.univ-lyon1.fr>
Signed-off-by: Nathan Payre <nathan.payre@etu.univ-lyon1.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
