Commit Graph

119 Commits

Author SHA1 Message Date
Junio C Hamano
9c7d0cc62f Merge branch 'jk/shallow-update-fix' into maint
* jk/shallow-update-fix:
  shallow: verify shallow file after taking lock
  shallow: automatically clean up shallow tempfiles
  shallow: use stat_validity to check for up-to-date file
2014-04-03 13:39:03 -07:00
Jeff King
0179c945fc shallow: automatically clean up shallow tempfiles
We sometimes write tempfiles of the form "shallow_XXXXXX"
during fetch/push operations with shallow repositories.
Under normal circumstances, we clean up the result when we
are done. However, we do no take steps to clean up after
ourselves when we exit due to die() or signal death.

This patch teaches the tempfile creation code to register
handlers to clean up after ourselves. To handle this, we
change the ownership semantics of the filename returned by
setup_temporary_shallow. It now keeps a copy of the filename
itself, and returns only a const pointer to it.

We can also do away with explicit tempfile removal in the
callers. They all exit not long after finishing with the
file, so they can rely on the auto-cleanup, simplifying the
code.

Note that we keep things simple and maintain only a single
filename to be cleaned. This is sufficient for the current
caller, but we future-proof it with a die("BUG").

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-02-27 12:07:13 -08:00
Nguyễn Thái Ngọc Duy
ff62eca7d1 fetch-pack: fix deepen shallow over smart http with no-done cap
In smart http, upload-pack adds new shallow lines at the beginning of
each rpc response. Only shallow lines from the first rpc call are
useful. After that they are thrown away. It's designed this way
because upload-pack is stateless and has no idea when its shallow
lines are helpful or not.

So after refs are negotiated with multi_ack_detailed and the server
thinks it learned enough, it sends "ACK obj-id ready", terminates the
rpc call and waits for the final rpc round. The client sends "done".
The server sends another response, which also has shallow lines at
the beginning, and the last "ACK obj-id" line.

When no-done is active, the last round is cut out, the server sends
"ACK obj-id ready" and "ACK obj-id" in the same rpc
response. fetch-pack is updated to recognize this and not send
"done". However it still tries to consume shallow lines, which are
never sent.

Update the code, make sure to skip consuming shallow lines when
no-done is enabled.

Reported-by: Jeff King <peff@peff.net>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-02-10 10:21:33 -08:00
Junio C Hamano
f583ace157 Merge branch 'jk/allow-fetch-onelevel-refname'
"git clone" would fail to clone from a repository that has a ref
directly under "refs/", e.g. "refs/stash", because different
validation paths do different things on such a refname.  Loosen the
client side's validation to allow such a ref.

* jk/allow-fetch-onelevel-refname:
  fetch-pack: do not filter out one-level refs
2014-01-27 10:44:14 -08:00
Junio C Hamano
92251b1b5b Merge branch 'nd/shallow-clone'
Fetching from a shallow-cloned repository used to be forbidden,
primarily because the codepaths involved were not carefully vetted
and we did not bother supporting such usage. This attempts to allow
object transfer out of a shallow-cloned repository in a controlled
way (i.e. the receiver become a shallow repository with truncated
history).

* nd/shallow-clone: (31 commits)
  t5537: fix incorrect expectation in test case 10
  shallow: remove unused code
  send-pack.c: mark a file-local function static
  git-clone.txt: remove shallow clone limitations
  prune: clean .git/shallow after pruning objects
  clone: use git protocol for cloning shallow repo locally
  send-pack: support pushing from a shallow clone via http
  receive-pack: support pushing to a shallow clone via http
  smart-http: support shallow fetch/clone
  remote-curl: pass ref SHA-1 to fetch-pack as well
  send-pack: support pushing to a shallow clone
  receive-pack: allow pushes that update .git/shallow
  connected.c: add new variant that runs with --shallow-file
  add GIT_SHALLOW_FILE to propagate --shallow-file to subprocesses
  receive/send-pack: support pushing from a shallow clone
  receive-pack: reorder some code in unpack()
  fetch: add --update-shallow to accept refs that update .git/shallow
  upload-pack: make sure deepening preserves shallow roots
  fetch: support fetching from a shallow repository
  clone: support remote shallow repository
  ...
2014-01-17 12:21:20 -08:00
Jeff King
4c22408111 fetch-pack: do not filter out one-level refs
Currently fetching a one-level ref like "refs/foo" does not
work consistently. The outer "git fetch" program filters the
list of refs, checking each against check_refname_format.
Then it feeds the result to do_fetch_pack to actually
negotiate the haves/wants and get the pack. The fetch-pack
code does its own filter, and it behaves differently.

The fetch-pack filter looks for refs in "refs/", and then
feeds everything _after_ the slash (i.e., just "foo") into
check_refname_format.  But check_refname_format is not
designed to look at a partial refname. It complains that the
ref has only one component, thinking it is at the root
(i.e., alongside "HEAD"), when in reality we just fed it a
partial refname.

As a result, we omit a ref like "refs/foo" from the pack
request, even though "git fetch" then tries to store the
resulting ref.  If we happen to get the object anyway (e.g.,
because the ref is contained in another ref we are
fetching), then the fetch succeeds. But if it is a unique
object, we fail when trying to update "refs/foo".

We can fix this by just passing the whole refname into
check_refname_format; we know the part we were omitting is
"refs/", which is acceptable in a refname. This at least
makes the checks consistent with each other.

This problem happens most commonly with "refs/stash", which
is the only one-level ref in wide use. However, our test
does not use "refs/stash", as we may later want to restrict
it specifically (not because it is one-level, but because
of the semantics of stashes).

We may also want to do away with the multiple levels of
filtering (which can cause problems when they are out of
sync), or even forbid one-level refs entirely. However,
those decisions can come later; this fixes the most
immediate problem, which is the mismatch between the two.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-01-15 12:37:24 -08:00
Ramsay Jones
feefdf62c1 shallow: remove unused code
Commit 58babfff ("shallow.c: the 8 steps to select new commits for
.git/shallow", 05-12-2013) added a function to implement step 5 of
the quoted eight steps, namely 'remove_nonexistent_ours_in_pack()'.
This function implements an optional optimization step in the new
shallow commit selection algorithm. However, this function has no
callers. (The commented out call sites would need to change, in
order to provide information required by the function.)

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Acked-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-01-06 09:05:40 -08:00
Junio C Hamano
ad70448576 Merge branch 'cc/starts-n-ends-with'
Remove a few duplicate implementations of prefix/suffix comparison
functions, and rename them to starts_with and ends_with.

* cc/starts-n-ends-with:
  replace {pre,suf}fixcmp() with {starts,ends}_with()
  strbuf: introduce starts_with() and ends_with()
  builtin/remote: remove postfixcmp() and use suffixcmp() instead
  environment: normalize use of prefixcmp() by removing " != 0"
2013-12-17 12:02:44 -08:00
Nguyễn Thái Ngọc Duy
48d25cae22 fetch: add --update-shallow to accept refs that update .git/shallow
The same steps are done as in when --update-shallow is not given. The
only difference is we now add all shallow commits in "ours" and
"theirs" to .git/shallow (aka "step 8").

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-10 16:14:17 -08:00
Nguyễn Thái Ngọc Duy
4820a33baa fetch: support fetching from a shallow repository
This patch just put together pieces from the 8 steps patch. We stop at
step 7 and reject refs that require new shallow commits.

Note that, by rejecting refs that require new shallow commits, we
leave dangling objects in the repo, which become "object islands" by
the next "git fetch" of the same source.

If the first fetch our "ours" set is zero and we do practically
nothing at step 7, "ours" is full at the next fetch and we may need to
walk through commits for reachability test. Room for improvement.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-10 16:14:17 -08:00
Nguyễn Thái Ngọc Duy
beea4152d9 clone: support remote shallow repository
Cloning from a shallow repository does not follow the "8 steps for new
.git/shallow" because if it does we need to get through step 6 for all
refs. That means commit walking down to the bottom.

Instead the rule to create .git/shallow is simpler and, more
importantly, cheap: if a shallow commit is found in the pack, it's
probably used (i.e. reachable from some refs), so we add it. Others
are dropped.

One may notice this method seems flawed by the word "probably". A
shallow commit may not be reachable from any refs at all if it's
attached to an object island (a group of objects that are not
reachable by any refs).

If that object island is not complete, a new fetch request may send
more objects to connect it to some ref. At that time, because we
incorrectly installed the shallow commit in this island, the user will
not see anything after that commit (fsck is still ok). This is not
desired.

Given that object islands are rare (C Git never sends such islands for
security reasons) and do not really harm the repository integrity, a
tradeoff is made to surprise the user occasionally but work faster
everyday.

A new option --strict could be added later that follows exactly the 8
steps. "git prune" can also learn to remove dangling objects _and_ the
shallow commits that are attached to them from .git/shallow.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-10 16:14:17 -08:00
Nguyễn Thái Ngọc Duy
a796ccee51 fetch-pack.c: move shallow update code out of fetch_pack()
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-10 16:14:16 -08:00
Nguyễn Thái Ngọc Duy
1a30f5a2f2 shallow.c: extend setup_*_shallow() to accept extra shallow commits
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-10 16:14:16 -08:00
Christian Couder
5955654823 replace {pre,suf}fixcmp() with {starts,ends}_with()
Leaving only the function definitions and declarations so that any
new topic in flight can still make use of the old functions, replace
existing uses of the prefixcmp() and suffixcmp() with new API
functions.

The change can be recreated by mechanically applying this:

    $ git grep -l -e prefixcmp -e suffixcmp -- \*.c |
      grep -v strbuf\\.c |
      xargs perl -pi -e '
        s|!prefixcmp\(|starts_with\(|g;
        s|prefixcmp\(|!starts_with\(|g;
        s|!suffixcmp\(|ends_with\(|g;
        s|suffixcmp\(|!ends_with\(|g;
      '

on the result of preparatory changes in this series.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-05 14:13:21 -08:00
Junio C Hamano
5bb62059f2 Merge branch 'jk/robustify-parse-commit'
* jk/robustify-parse-commit:
  checkout: do not die when leaving broken detached HEAD
  use parse_commit_or_die instead of custom message
  use parse_commit_or_die instead of segfaulting
  assume parse_commit checks for NULL commit
  assume parse_commit checks commit->object.parsed
  log_tree_diff: die when we fail to parse a commit
2013-12-05 12:54:01 -08:00
Junio C Hamano
832ee79ab8 Merge branch 'jl/pack-transfer-avoid-double-close'
The codepath that send_pack() calls pack_objects() mistakenly
closed the same file descriptor twice, leading to potentially
closing a wrong file descriptor that was opened in the meantime.

* jl/pack-transfer-avoid-double-close:
  Clear fd after closing to avoid double-close error
2013-10-30 12:10:45 -07:00
Jeff King
0064053bd7 assume parse_commit checks commit->object.parsed
The parse_commit function will check the "parsed" flag of
the object and do nothing if it is set. There is no need
for callers to check the flag themselves, and doing so only
clutters the code.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-10-24 15:43:50 -07:00
Junio C Hamano
6ba0d9551a Merge branch 'nd/fetch-into-shallow' into maint
When there is no sufficient overlap between old and new history
during a "git fetch" into a shallow repository, objects that the
sending side knows the receiving end has were unnecessarily sent.

* nd/fetch-into-shallow:
  Add testcase for needless objects during a shallow fetch
  list-objects: mark more commits as edges in mark_edges_uninteresting
  list-objects: reduce one argument in mark_edges_uninteresting
  upload-pack: delegate rev walking in shallow fetch to pack-objects
  shallow: add setup_temporary_shallow()
  shallow: only add shallow graft points to new shallow file
  move setup_alternate_shallow and write_shallow_commits to shallow.c
2013-10-23 13:32:17 -07:00
Jens Lindstrom
37cb1dd671 Clear fd after closing to avoid double-close error
In send_pack(), clear the fd passed to pack_objects() by setting
it to -1, since pack_objects() closes the fd (via a call to
run_command()).  Likewise, in get_pack(), clear the fd passed to
run_command().

Not doing so risks having git_transport_push(), caller of
send_pack(), closing the fd again, possibly incorrectly closing
some other open file; or similarly with fetch_refs_from_pack(),
indirect caller of get_pack().

Signed-off-by: Jens Lindström <jl@opera.com>
Acked-by: Jeff King <peff@peff.net>
Acked-by: Duy Nguyen <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-10-23 09:07:09 -07:00
Jonathan Nieder
40b77322d2 Merge branch 'nd/fetch-pack-error-reporting-fix'
* nd/fetch-pack-error-reporting-fix:
  fetch-pack.c: show correct command name that fails
2013-09-24 23:27:02 -07:00
Junio C Hamano
238504b014 Merge branch 'nd/fetch-into-shallow'
When there is no sufficient overlap between old and new history
during a fetch into a shallow repository, we unnecessarily sent
objects the sending side knows the receiving end has.

* nd/fetch-into-shallow:
  Add testcase for needless objects during a shallow fetch
  list-objects: mark more commits as edges in mark_edges_uninteresting
  list-objects: reduce one argument in mark_edges_uninteresting
  upload-pack: delegate rev walking in shallow fetch to pack-objects
  shallow: add setup_temporary_shallow()
  shallow: only add shallow graft points to new shallow file
  move setup_alternate_shallow and write_shallow_commits to shallow.c
2013-09-20 12:25:32 -07:00
Nguyễn Thái Ngọc Duy
4727f671b8 fetch-pack.c: show correct command name that fails
When --shallow-file is added to the command line, it has to be
before the subcommand name, the first argument won't be the command
name any more. Stop assuming that and keep track of the command name
explicitly.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-09-18 11:11:53 -07:00
Junio C Hamano
2233ad4534 Merge branch 'jc/push-cas'
Allow a safer "rewind of the remote tip" push than blind "--force",
by requiring that the overwritten remote ref to be unchanged since
the new history to replace it was prepared.

The machinery is more or less ready.  The "--force" option is again
the big red button to override any safety, thanks to J6t's sanity
(the original round allowed --lockref to defeat --force).

The logic to choose the default implemented here is fragile
(e.g. "git fetch" after seeing a failure will update the
remote-tracking branch and will make the next "push" pass,
defeating the safety pretty easily).  It is suitable only for the
simplest workflows, and it may hurt users more than it helps them.

* jc/push-cas:
  push: teach --force-with-lease to smart-http transport
  send-pack: fix parsing of --force-with-lease option
  t5540/5541: smart-http does not support "--force-with-lease"
  t5533: test "push --force-with-lease"
  push --force-with-lease: tie it all together
  push --force-with-lease: implement logic to populate old_sha1_expect[]
  remote.c: add command line option parser for "--force-with-lease"
  builtin/push.c: use OPT_BOOL, not OPT_BOOLEAN
  cache.h: move remote/connect API out of it
2013-09-09 14:30:29 -07:00
Junio C Hamano
2ea3df68e8 Merge branch 'nd/fetch-pack-shallow-fix' into maint
The recent "short-cut clone connectivity check" topic broke a shallow
repository when a fetch operation tries to auto-follow tags.

* nd/fetch-pack-shallow-fix:
  fetch-pack: do not remove .git/shallow file when --depth is not specified
2013-09-05 14:40:58 -07:00
Junio C Hamano
e250020cd0 Merge branch 'nd/fetch-pack-shallow-fix'
The recent "short-cut clone connectivity check" topic broke a
shallow repository when a fetch operation tries to auto-follow tags.

* nd/fetch-pack-shallow-fix:
  fetch-pack: do not remove .git/shallow file when --depth is not specified
2013-08-30 10:05:55 -07:00
Nguyễn Thái Ngọc Duy
6da8bdcbbf fetch-pack: do not remove .git/shallow file when --depth is not specified
fetch_pack() can remove .git/shallow file when a shallow repository
becomes a full one again. This behavior is triggered incorrectly when
tags are also fetched because fetch_pack() will be called twice. At
the first fetch_pack() call:

 - shallow_lock is set up
 - alternate_shallow_file points to shallow_lock.filename, which is
   "shallow.lock"
 - commit_lock_file is called, which sets shallow_lock.filename to "".
   alternate_shallow_file also becomes "" because it points to the
   same memory.

At the second call, setup_alternate_shallow() is not called and
alternate_shallow_file remains "". It's mistaken as unshallow case and
.git/shallow is removed. The end result is a broken repository.

Fix this by always initializing alternate_shallow_file when
fetch_pack() is called. As an extra measure, check if args->depth > 0
before commit/rollback shallow file.

Reported-by: Kacper Kornet <kornet@camk.edu.pl>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-08-25 22:56:03 -07:00
Nguyễn Thái Ngọc Duy
3125fe528b move setup_alternate_shallow and write_shallow_commits to shallow.c
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-08-18 13:00:17 -07:00
Junio C Hamano
47a5918536 cache.h: move remote/connect API out of it
The definition of "struct ref" in "cache.h", a header file so
central to the system, always confused me.  This structure is not
about the local ref used by sha1-name API to name local objects.

It is what refspecs are expanded into, after finding out what refs
the other side has, to define what refs are updated after object
transfer succeeds to what values.  It belongs to "remote.h" together
with "struct refspec".

While we are at it, also move the types and functions related to the
Git transport connection to a new header file connect.h

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-07-08 14:34:24 -07:00
Jeff King
099327b552 fetch-pack: avoid quadratic behavior in rev_list_push
When we call find_common to start finding common ancestors
with the remote side of a fetch, the first thing we do is
insert the tip of each ref into our rev_list linked list. We
keep the list sorted the whole time with
commit_list_insert_by_date, which means our insertion ends
up doing O(n^2) timestamp comparisons.

We could teach rev_list_push to use an unsorted list, and
then sort it once after we have added each ref. However, in
get_rev, we process the list by popping commits off the
front and adding parents back in timestamp-sorted order. So
that procedure would still operate on the large list.

Instead, we can replace the linked list with a heap-based
priority queue, which can do O(log n) insertion, making the
whole insertion procedure O(n log n).

As a result of switching to the prio_queue struct, we fix
two minor bugs:

  1. When we "pop" a commit in get_rev, and when we clear
     the rev_list in find_common, we do not take care to
     free the "struct commit_list", and just leak its
     memory. With the prio_queue implementation, the memory
     management is handled for us.

  2. In get_rev, we look at the head commit of the list,
     possibly push its parents onto the list, and then "pop"
     the front of the list off, assuming it is the same
     element that we just peeked at. This is typically going
     to be the case, but would not be in the face of clock
     skew: the parents are inserted by date, and could
     potentially be inserted at the head of the list if they
     have a timestamp newer than their descendent. In this
     case, we would accidentally pop the parent, and never
     process it at all.

     The new implementation pulls the commit off of the
     queue as we examine it, and so does not suffer from
     this problem.

With this patch, a fetch of a single commit into a
repository with 50,000 refs went from:

  real    0m7.984s
  user    0m7.852s
  sys     0m0.120s

to:

  real    0m2.017s
  user    0m1.884s
  sys     0m0.124s

Before this patch, a larger case with 370K refs still had
not completed after tens of minutes; with this patch, it
completes in about 12 seconds.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-07-02 12:05:46 -07:00
Jeff King
16445242ed fetch-pack: avoid quadratic list insertion in mark_complete
We insert the commit pointed to by each ref one-by-one into
the "complete" commit_list using insert_by_date. Because
each insertion is O(n), we end up with O(n^2) behavior.

This typically doesn't matter, because the number of refs is
reasonably small. And even if there are a lot of refs, they
often point to a smaller set of objects (in which case the
optimization in commit ea5f220 keeps our "n" small).

However, in pathological repositories (hundreds of thousands
of refs, each pointing to a unique commit), this quadratic
behavior can make a difference. Since we do not care about
the list order until we have finished building it, we can
simply keep it unsorted during the insertion phase, then
sort it afterwards.

On a repository like the one described above, this dropped
the time to do a no-op fetch from 2.0s to 1.7s. On normal
repositories, it probably does not matter at all, but it
does not hurt to protect ourselves from pathological cases.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-07-02 12:03:34 -07:00
Nguyễn Thái Ngọc Duy
c6807a40dc clone: open a shortcut for connectivity check
In order to make sure the cloned repository is good, we run "rev-list
--objects --not --all $new_refs" on the repository. This is expensive
on large repositories. This patch attempts to mitigate the impact in
this special case.

In the "good" clone case, we only have one pack. If all of the
following are met, we can be sure that all objects reachable from the
new refs exist, which is the intention of running "rev-list ...":

 - all refs point to an object in the pack
 - there are no dangling pointers in any object in the pack
 - no objects in the pack point to objects outside the pack

The second and third checks can be done with the help of index-pack as
a slight variation of --strict check (which introduces a new condition
for the shortcut: pack transfer must be used and the number of objects
large enough to call index-pack). The first is checked in
check_everything_connected after we get an "ok" from index-pack.

"index-pack + new checks" is still faster than the current "index-pack
+ rev-list", which is the whole point of this patch. If any of the
conditions fail, we fall back to the good old but expensive "rev-list
..". In that case it's even more expensive because we have to pay for
the new checks in index-pack. But that should only happen when the
other side is either buggy or malicious.

Cloning linux-2.6 over file://

        before         after
real    3m25.693s      2m53.050s
user    5m2.037s       4m42.396s
sys     0m13.750s      0m16.574s

A more realistic test with ssh:// over wireless

        before         after
real    11m26.629s     10m4.213s
user    5m43.196s      5m19.444s
sys     0m35.812s      0m37.630s

This shortcut is not applied to shallow clones, partly because shallow
clones should have no more objects than a usual fetch and the cost of
rev-list is acceptable, partly to avoid dealing with corner cases when
grafting is involved.

This shortcut does not apply to unpack-objects code path either
because the number of objects must be small in order to trigger that
code path.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-05-28 08:07:20 -07:00
Nguyễn Thái Ngọc Duy
6035d6aad8 fetch-pack: prepare updated shallow file before fetching the pack
index-pack --strict looks up and follows parent commits. If shallow
information is not ready by the time index-pack is run, index-pack may
be led to non-existent objects. Make fetch-pack save shallow file to
disk before invoking index-pack.

git learns new global option --shallow-file to pass on the alternate
shallow file path. Undocumented (and not even support --shallow-file=
syntax) because it's unlikely to be used again elsewhere.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-05-28 08:06:08 -07:00
Junio C Hamano
e013bdab0f Merge branch 'jk/pkt-line-cleanup'
Clean up pkt-line API, implementation and its callers to make them
more robust.

* jk/pkt-line-cleanup:
  do not use GIT_TRACE_PACKET=3 in tests
  remote-curl: always parse incoming refs
  remote-curl: move ref-parsing code up in file
  remote-curl: pass buffer straight to get_remote_heads
  teach get_remote_heads to read from a memory buffer
  pkt-line: share buffer/descriptor reading implementation
  pkt-line: provide a LARGE_PACKET_MAX static buffer
  pkt-line: move LARGE_PACKET_MAX definition from sideband
  pkt-line: teach packet_read_line to chomp newlines
  pkt-line: provide a generic reading function with options
  pkt-line: drop safe_write function
  pkt-line: move a misplaced comment
  write_or_die: raise SIGPIPE when we get EPIPE
  upload-archive: use argv_array to store client arguments
  upload-archive: do not copy repo name
  send-pack: prefer prefixcmp over memcmp in receive_status
  fetch-pack: fix out-of-bounds buffer offset in get_ack
  upload-pack: remove packet debugging harness
  upload-pack: do not add duplicate objects to shallow list
  upload-pack: use get_sha1_hex to parse "shallow" lines
2013-04-01 08:59:37 -07:00
Junio C Hamano
e4e1c54990 Merge branch 'jc/fetch-raw-sha1'
Allows requests to fetch objects at any tip of refs (including
hidden ones).  It seems that there may be use cases even outside
Gerrit (e.g. $gmane/215701).

* jc/fetch-raw-sha1:
  fetch: fetch objects by their exact SHA-1 object names
  upload-pack: optionally allow fetching from the tips of hidden refs
  fetch: use struct ref to represent refs to be fetched
  parse_fetch_refspec(): clarify the codeflow a bit
2013-03-21 14:02:27 -07:00
Jeff King
74543a0423 pkt-line: provide a LARGE_PACKET_MAX static buffer
Most of the callers of packet_read_line just read into a
static 1000-byte buffer (callers which handle arbitrary
binary data already use LARGE_PACKET_MAX). This works fine
in practice, because:

  1. The only variable-sized data in these lines is a ref
     name, and refs tend to be a lot shorter than 1000
     characters.

  2. When sending ref lines, git-core always limits itself
     to 1000 byte packets.

However, the only limit given in the protocol specification
in Documentation/technical/protocol-common.txt is
LARGE_PACKET_MAX; the 1000 byte limit is mentioned only in
pack-protocol.txt, and then only describing what we write,
not as a specific limit for readers.

This patch lets us bump the 1000-byte limit to
LARGE_PACKET_MAX. Even though git-core will never write a
packet where this makes a difference, there are two good
reasons to do this:

  1. Other git implementations may have followed
     protocol-common.txt and used a larger maximum size. We
     don't bump into it in practice because it would involve
     very long ref names.

  2. We may want to increase the 1000-byte limit one day.
     Since packets are transferred before any capabilities,
     it's difficult to do this in a backwards-compatible
     way. But if we bump the size of buffer the readers can
     handle, eventually older versions of git will be
     obsolete enough that we can justify bumping the
     writers, as well. We don't have plans to do this
     anytime soon, but there is no reason not to start the
     clock ticking now.

Just bumping all of the reading bufs to LARGE_PACKET_MAX
would waste memory. Instead, since most readers just read
into a temporary buffer anyway, let's provide a single
static buffer that all callers can use. We can further wrap
this detail away by having the packet_read_line wrapper just
use the buffer transparently and return a pointer to the
static storage.  That covers most of the cases, and the
remaining ones already read into their own LARGE_PACKET_MAX
buffers.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-02-20 13:42:22 -08:00
Jeff King
819b929d33 pkt-line: teach packet_read_line to chomp newlines
The packets sent during ref negotiation are all terminated
by newline; even though the code to chomp these newlines is
short, we end up doing it in a lot of places.

This patch teaches packet_read_line to auto-chomp the
trailing newline; this lets us get rid of a lot of inline
chomping code.

As a result, some call-sites which are not reading
line-oriented data (e.g., when reading chunks of packfiles
alongside sideband) transition away from packet_read_line to
the generic packet_read interface. This patch converts all
of the existing callsites.

Since the function signature of packet_read_line does not
change (but its behavior does), there is a possibility of
new callsites being introduced in later commits, silently
introducing an incompatibility.  However, since a later
patch in this series will change the signature, such a
commit would have to be merged directly into this commit,
not to the tip of the series; we can therefore ignore the
issue.

This is an internal cleanup and should produce no change of
behavior in the normal case. However, there is one corner
case to note. Callers of packet_read_line have never been
able to tell the difference between a flush packet ("0000")
and an empty packet ("0004"), as both cause packet_read_line
to return a length of 0. Readers treat them identically,
even though Documentation/technical/protocol-common.txt says
we must not; it also says that implementations should not
send an empty pkt-line.

By stripping out the newline before the result gets to the
caller, we will now treat the newline-only packet ("0005\n")
the same as an empty packet, which in turn gets treated like
a flush packet. In practice this doesn't matter, as neither
empty nor newline-only packets are part of git's protocols
(at least not for the line-oriented bits, and readers who
are not expecting line-oriented packets will be calling
packet_read directly, anyway). But even if we do decide to
care about the distinction later, it is orthogonal to this
patch.  The right place to tighten would be to stop treating
empty packets as flush packets, and this change does not
make doing so any harder.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-02-20 13:42:21 -08:00
Jeff King
cdf4fb8e33 pkt-line: drop safe_write function
This is just write_or_die by another name. The one
distinction is that write_or_die will treat EPIPE specially
by suppressing error messages. That's fine, as we die by
SIGPIPE anyway (and in the off chance that it is disabled,
write_or_die will simulate it).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-02-20 13:42:21 -08:00
Jeff King
030e9dd64f fetch-pack: fix out-of-bounds buffer offset in get_ack
When we read acks from the remote, we expect either:

  ACK <sha1>

or

  ACK <sha1> <multi-ack-flag>

We parse the "ACK <sha1>" bit from the line, and then start
looking for the flag strings at "line+45"; if we don't have
them, we assume it's of the first type.  But if we do have
the first type, then line+45 is not necessarily inside our
string at all!

It turns out that this works most of the time due to the way
we parse the packets. They should come in with a newline,
and packet_read puts an extra NUL into the buffer, so we end
up with:

  ACK <sha1>\n\0

with the newline at offset 44 and the NUL at offset 45. We
then strip the newline, putting a NUL at offset 44. So
when we look at "line+45", we are looking past the end of
our string; but it's OK, because we hit the terminator from
the original string.

This breaks down, however, if the other side does not
terminate their packets with a newline. In that case, our
packet is one character shorter, and we start looking
through uninitialized memory for the flag. No known
implementation sends such a packet, so it has never come up
in practice.

This patch tightens the check by looking for a short,
flagless ACK before trying to parse the flag.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-02-20 13:42:21 -08:00
Junio C Hamano
6e7b66eebd fetch: fetch objects by their exact SHA-1 object names
Teach "git fetch" to accept an exact SHA-1 object name the user may
obtain out of band on the LHS of a pathspec, and send it on a "want"
message when the server side advertises the allow-tip-sha1-in-want
capability.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-02-07 14:07:53 -08:00
Junio C Hamano
f2db854d24 fetch: use struct ref to represent refs to be fetched
Even though "git fetch" has full infrastructure to parse refspecs to
be fetched and match them against the list of refs to come up with
the final list of refs to be fetched, the list of refs that are
requested to be fetched were internally converted to a plain list of
strings at the transport layer and then passed to the underlying
fetch-pack driver.

Stop this conversion and instead pass around an array of refs.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-02-07 13:53:59 -08:00
Junio C Hamano
4acfff9dda Merge branch 'jk/gc-auto-after-fetch'
Help "fetch only" repositories that do not trigger "gc --auto"
often enough.

* jk/gc-auto-after-fetch:
  fetch-pack: avoid repeatedly re-scanning pack directory
  fetch: run gc --auto after fetching
2013-02-01 12:40:16 -08:00
Junio C Hamano
012a1bb524 Merge branch 'jk/maint-gc-auto-after-fetch' into jk/gc-auto-after-fetch
* jk/maint-gc-auto-after-fetch:
  fetch-pack: avoid repeatedly re-scanning pack directory
  fetch: run gc --auto after fetching
2013-01-26 19:42:09 -08:00
Junio C Hamano
8cabd200d2 Merge branch 'mk/qnx'
Port to QNX.

* mk/qnx:
  Port to QNX
  Make lock local to fetch_pack
2013-01-03 10:28:33 -08:00
Nguyễn Thái Ngọc Duy
745f7a8cac fetch-pack: move core code to libgit.a
fetch_pack() is used by transport.c, part of libgit.a while it stays
in builtin/fetch-pack.c. Move it to fetch-pack.c so that we won't get
undefined reference if a program that uses libgit.a happens to pull it
in.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
2012-10-29 03:40:29 -04:00
Daniel Barkalow
2d4177c01c Make fetch-pack a builtin with an internal API
Signed-off-by: Daniel Barkalow <barkalow@iabervon.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-09-19 03:22:30 -07:00
Junio C Hamano
a6080a0a44 War on whitespace
This uses "git-apply --whitespace=strip" to fix whitespace errors that have
crept in to our source files over time.  There are a few files that need
to have trailing whitespaces (most notably, test vectors).  The results
still passes the test, and build result in Documentation/ area is unchanged.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-06-07 00:04:01 -07:00
Michael S. Tsirkin
7841ce7985 connect: display connection progress
Make git notify the user about host resolution/connection attempts.
This is useful both as a progress indicator on slow links, and helps
reassure the user there are no firewall problems.

Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-05-16 12:48:18 -07:00
Junio C Hamano
3ddad98b74 Merge branch 'js/fetch-progress' (early part)
* 'js/fetch-progress' (early part):
  Fixup no-progress for fetch & clone
  fetch & clone: do not output progress when not on a tty

Conflicts:

	git-fetch.sh
2007-03-04 17:31:21 -08:00
Johannes Schindelin
b0e908977e Fixup no-progress for fetch & clone
The intent of the commit 'fetch & clone: do not output progress when
not on a tty' was to make fetching and cloning less chatty when
output was not redirected (such as in a cron job).

However, there was a serious thinko in that commit. It assumed that
the client _and_ the server got this update at the same time. But
this is obviously not the case, and therefore upload-pack died on
seeing the option "--no-progress".

This patch fixes that issue by making it a protocol option. So, until
your server is updated, you still see the progress, but once the
server has this patch, it will be quiet.

A minor issue was also fixed: when cloning, the checkout did not
heed no_progress.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-02-24 00:26:18 -08:00
Junio C Hamano
599065a3bb prefixcmp(): fix-up mechanical conversion.
Previous step converted use of strncmp() with literal string
mechanically even when the result is only used as a boolean:

    if (!strncmp("foo", arg, 3)) ==> if (!(-prefixcmp(arg, "foo")))

This step manually cleans them up to read:

    if (!prefixcmp(arg, "foo"))

Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-02-20 22:03:15 -08:00