Commit Graph

254 Commits

Author SHA1 Message Date
Junio C Hamano
b21089db6a Merge branch 'db/push-sign-if-asked'
The client side codepaths in "git push" have been cleaned up
and the user can request to perform an optional "signed push",
i.e. sign only when the other end accepts signed push.

* db/push-sign-if-asked:
  push: add a config option push.gpgSign for default signed pushes
  push: support signing pushes iff the server supports it
  builtin/send-pack.c: use parse_options API
  config.c: rename git_config_maybe_bool_text and export it as git_parse_maybe_bool
  transport: remove git_transport_options.push_cert
  gitremote-helpers.txt: document pushcert option
  Documentation/git-send-pack.txt: document --signed
  Documentation/git-send-pack.txt: wrap long synopsis line
  Documentation/git-push.txt: document when --signed may fail
2015-08-31 15:39:08 -07:00
Junio C Hamano
1f76a10b2d write_file(): drop caller-supplied LF from calls to create a one-liner file
All of the callsites covered by this change call write_file() or
write_file_gently() to create a one-liner file.  Drop the caller
supplied LF and let these callees to append it as necessary.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-25 12:49:19 -07:00
Junio C Hamano
12d6ce1dba write_file(): drop "fatal" parameter
All callers except three passed 1 for the "fatal" parameter to ask
this function to die upon error, but to a casual reader of the code,
it was not all obvious what that 1 meant.  Instead, split the
function into two based on a common write_file_v() that takes the
flag, introduce write_file_gently() as a new way to attempt creating
a file without dying on error, and make three callers to call it.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-24 13:09:02 -07:00
Dave Borowitz
30261094b1 push: support signing pushes iff the server supports it
Add a new flag --sign=true (or --sign=false), which means the same
thing as the original --signed (or --no-signed).  Give it a third
value --sign=if-asked to tell push and send-pack to send a push
certificate if and only if the server advertised a push cert nonce.

If not, warn the user that their push may not be as secure as they
thought.

Signed-off-by: Dave Borowitz <dborowitz@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-19 12:58:45 -07:00
Dave Borowitz
87c0d08b3d transport: remove git_transport_options.push_cert
This field was set in transport_set_option, but never read in the push
code. The push code basically ignores the smart_options field
entirely, and derives its options from the flags arguments to the
push* callbacks. Note that in git_transport_push there are already
several args set from flags that have no corresponding field in
git_transport_options; after this change, push_cert is just like
those.

Signed-off-by: Dave Borowitz <dborowitz@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-19 12:41:54 -07:00
Michael Haggerty
1700cb3b05 write_one_ref(): rewrite to take an object_id argument
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-05-25 12:19:36 -07:00
Michael Haggerty
f31ba7e116 write_refs_to_temp_dir(): convert local variable sha1 to object_id
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-05-25 12:19:36 -07:00
Michael Haggerty
2b2a5be394 each_ref_fn: change to take an object_id parameter
Change typedef each_ref_fn to take a "const struct object_id *oid"
parameter instead of "const unsigned char *sha1".

To aid this transition, implement an adapter that can be used to wrap
old-style functions matching the old typedef, which is now called
"each_ref_sha1_fn"), and make such functions callable via the new
interface. This requires the old function and its cb_data to be
wrapped in a "struct each_ref_fn_sha1_adapter", and that object to be
used as the cb_data for an adapter function, each_ref_fn_adapter().

This is an enormous diff, but most of it consists of simple,
mechanical changes to the sites that call any of the "for_each_ref"
family of functions. Subsequent to this change, the call sites can be
rewritten one by one to use the new interface.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-05-25 12:19:27 -07:00
Junio C Hamano
68a2e6a2c8 Merge branch 'nd/multiple-work-trees'
A replacement for contrib/workdir/git-new-workdir that does not
rely on symbolic links and make sharing of objects and refs safer
by making the borrowee and borrowers aware of each other.

* nd/multiple-work-trees: (41 commits)
  prune --worktrees: fix expire vs worktree existence condition
  t1501: fix test with split index
  t2026: fix broken &&-chain
  t2026 needs procondition SANITY
  git-checkout.txt: a note about multiple checkout support for submodules
  checkout: add --ignore-other-wortrees
  checkout: pass whole struct to parse_branchname_arg instead of individual flags
  git-common-dir: make "modules/" per-working-directory directory
  checkout: do not fail if target is an empty directory
  t2025: add a test to make sure grafts is working from a linked checkout
  checkout: don't require a work tree when checking out into a new one
  git_path(): keep "info/sparse-checkout" per work-tree
  count-objects: report unused files in $GIT_DIR/worktrees/...
  gc: support prune --worktrees
  gc: factor out gc.pruneexpire parsing code
  gc: style change -- no SP before closing parenthesis
  checkout: clean up half-prepared directories in --to mode
  checkout: reject if the branch is already checked out elsewhere
  prune: strategies for linked checkouts
  checkout: support checking out into a new working directory
  ...
2015-05-11 14:23:39 -07:00
Junio C Hamano
2f6ef71387 Merge branch 'jk/fetch-pack'
"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
2015-03-25 12:54:25 -07:00
Junio C Hamano
daea6fca35 Merge branch 'rs/use-isxdigit'
Code cleanup.

* rs/use-isxdigit:
  use isxdigit() for checking if a character is a hexadecimal digit
2015-03-20 13:11:52 -07:00
Jeff King
626df76e3d fetch_refs_via_pack: free extra copy of refs
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>
2015-03-19 14:11:35 -07:00
René Scharfe
6f75d45b24 use isxdigit() for checking if a character is a hexadecimal digit
Use the standard function isxdigit() to make the intent clearer and
avoid using magic constants.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-03-10 15:44:41 -07:00
Junio C Hamano
39fa6112ec Merge branch 'sb/atomic-push'
"git push" has been taught a "--atomic" option that makes push to
update more than one ref an "all-or-none" affair.

* sb/atomic-push:
  Document receive.advertiseatomic
  t5543-atomic-push.sh: add basic tests for atomic pushes
  push.c: add an --atomic argument
  send-pack.c: add --atomic command line argument
  send-pack: rename ref_update_to_be_sent to check_to_send_update
  receive-pack.c: negotiate atomic push support
  receive-pack.c: add execute_commands_atomic function
  receive-pack.c: move transaction handling in a central place
  receive-pack.c: move iterating over all commands outside execute_commands
  receive-pack.c: die instead of error in case of possible future bug
  receive-pack.c: shorten the execute_commands loop over all commands
2015-02-11 13:43:51 -08:00
Ronnie Sahlberg
d0e8e09cd8 push.c: add an --atomic argument
Add a command line argument to the git push command to request atomic
pushes.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-01-07 19:56:44 -08:00
Ronnie Sahlberg
4ff17f10c4 send-pack.c: add --atomic command line argument
This adds support to send-pack to negotiate and use atomic pushes
iff the server supports it. Atomic pushes are activated by a new command
line flag --atomic.

In order to do this we also need to change the semantics for send_pack()
slightly. The existing send_pack() function actually doesn't send all the
refs back to the server when multiple refs are involved, for example
when using --all. Several of the failure modes for pushes can already be
detected locally in the send_pack client based on the information from the
initial server side list of all the refs as generated by receive-pack.
Any such refs that we thus know would fail to push are thus pruned from
the list of refs we send to the server to update.

For atomic pushes, we have to deal thus with both failures that are detected
locally as well as failures that are reported back from the server. In order
to do so we treat all local failures as push failures too.

We introduce a new status code REF_STATUS_ATOMIC_PUSH_FAILED so we can
flag all refs that we would normally have tried to push to the server
but we did not due to local failures. This is to improve the error message
back to the end user to flag that "these refs failed to update since the
atomic push operation failed."

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-01-07 19:56:44 -08:00
René Scharfe
6b33894f99 transport: simplify duplicating a substring in transport_get() using xmemdupz()
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-29 09:39:23 -08:00
Nguyễn Thái Ngọc Duy
91aacda85a use new wrapper write_file() for simple file writing
This fixes common problems in these code about error handling,
forgetting to close the file handle after fprintf() fails, or not
printing out the error string..

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-01 11:00:16 -08:00
Junio C Hamano
95d2255bfe Merge branch 'sb/plug-transport-leak'
Code clean-up.

* sb/plug-transport-leak:
  .mailmap: add Stefan Bellers corporate mail address
  transport: free leaking head in transport_print_push_status()
2014-10-24 15:00:09 -07:00
Stefan Beller
dc76c7f783 transport: free leaking head in transport_print_push_status()
Found by scan.coverity.com (ID: 1248110)

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-21 11:01:18 -07:00
Ronnie Sahlberg
7695d118e5 refs.c: change resolve_ref_unsafe reading argument to be a flags field
resolve_ref_unsafe takes a boolean argument for reading (a nonexistent ref
resolves successfully for writing but not for reading).  Change this to be
a flags field instead, and pass the new constant RESOLVE_REF_READING when
we want this behaviour.

While at it, swap two of the arguments in the function to put output
arguments at the end.  As a nice side effect, this ensures that we can
catch callers that were unaware of the new API so they can be audited.

Give the wrapper functions resolve_refdup and read_ref_full the same
treatment for consistency.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-15 10:47:24 -07:00
Junio C Hamano
fb06b5280e Merge branch 'jc/push-cert'
Allow "git push" request to be signed, so that it can be verified and
audited, using the GPG signature of the person who pushed, that the
tips of branches at a public repository really point the commits
the pusher wanted to, without having to "trust" the server.

* jc/push-cert: (24 commits)
  receive-pack::hmac_sha1(): copy the entire SHA-1 hash out
  signed push: allow stale nonce in stateless mode
  signed push: teach smart-HTTP to pass "git push --signed" around
  signed push: fortify against replay attacks
  signed push: add "pushee" header to push certificate
  signed push: remove duplicated protocol info
  send-pack: send feature request on push-cert packet
  receive-pack: GPG-validate push certificates
  push: the beginning of "git push --signed"
  pack-protocol doc: typofix for PKT-LINE
  gpg-interface: move parse_signature() to where it should be
  gpg-interface: move parse_gpg_output() to where it should be
  send-pack: clarify that cmds_sent is a boolean
  send-pack: refactor inspecting and resetting status and sending commands
  send-pack: rename "new_refs" to "need_pack_data"
  receive-pack: factor out capability string generation
  send-pack: factor out capability string generation
  send-pack: always send capabilities
  send-pack: refactor decision to send update per ref
  send-pack: move REF_STATUS_REJECT_NODELETE logic a bit higher
  ...
2014-10-08 13:05:25 -07:00
Junio C Hamano
9be89160e7 signed push: add "pushee" header to push certificate
Record the URL of the intended recipient for a push (after
anonymizing it if it has authentication material) on a new "pushee
URL" header.  Because the networking configuration (SSH-tunnels,
proxies, etc.) on the pushing user's side varies, the receiving
repository may not know the single canonical URL all the pushing
users would refer it as (besides, many sites allow pushing over
ssh://host/path and https://host/path protocols to the same
repository but with different local part of the path).  So this
value may not be reliably used for replay-attack prevention
purposes, but this will still serve as a human readable hint to
identify the repository the certificate refers to.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-09-15 13:23:28 -07:00
Junio C Hamano
a85b377d04 push: the beginning of "git push --signed"
While signed tags and commits assert that the objects thusly signed
came from you, who signed these objects, there is not a good way to
assert that you wanted to have a particular object at the tip of a
particular branch.  My signing v2.0.1 tag only means I want to call
the version v2.0.1, and it does not mean I want to push it out to my
'master' branch---it is likely that I only want it in 'maint', so
the signature on the object alone is insufficient.

The only assurance to you that 'maint' points at what I wanted to
place there comes from your trust on the hosting site and my
authentication with it, which cannot easily audited later.

Introduce a mechanism that allows you to sign a "push certificate"
(for the lack of better name) every time you push, asserting that
what object you are pushing to update which ref that used to point
at what other object.  Think of it as a cryptographic protection for
ref updates, similar to signed tags/commits but working on an
orthogonal axis.

The basic flow based on this mechanism goes like this:

 1. You push out your work with "git push --signed".

 2. The sending side learns where the remote refs are as usual,
    together with what protocol extension the receiving end
    supports.  If the receiving end does not advertise the protocol
    extension "push-cert", an attempt to "git push --signed" fails.

    Otherwise, a text file, that looks like the following, is
    prepared in core:

	certificate version 0.1
	pusher Junio C Hamano <gitster@pobox.com> 1315427886 -0700

	7339ca65... 21580ecb... refs/heads/master
	3793ac56... 12850bec... refs/heads/next

    The file begins with a few header lines, which may grow as we
    gain more experience.  The 'pusher' header records the name of
    the signer (the value of user.signingkey configuration variable,
    falling back to GIT_COMMITTER_{NAME|EMAIL}) and the time of the
    certificate generation.  After the header, a blank line follows,
    followed by a copy of the protocol message lines.

    Each line shows the old and the new object name at the tip of
    the ref this push tries to update, in the way identical to how
    the underlying "git push" protocol exchange tells the ref
    updates to the receiving end (by recording the "old" object
    name, the push certificate also protects against replaying).  It
    is expected that new command packet types other than the
    old-new-refname kind will be included in push certificate in the
    same way as would appear in the plain vanilla command packets in
    unsigned pushes.

    The user then is asked to sign this push certificate using GPG,
    formatted in a way similar to how signed tag objects are signed,
    and the result is sent to the other side (i.e. receive-pack).

    In the protocol exchange, this step comes immediately before the
    sender tells what the result of the push should be, which in
    turn comes before it sends the pack data.

 3. When the receiving end sees a push certificate, the certificate
    is written out as a blob.  The pre-receive hook can learn about
    the certificate by checking GIT_PUSH_CERT environment variable,
    which, if present, tells the object name of this blob, and make
    the decision to allow or reject this push.  Additionally, the
    post-receive hook can also look at the certificate, which may be
    a good place to log all the received certificates for later
    audits.

Because a push certificate carry the same information as the usual
command packets in the protocol exchange, we can omit the latter
when a push certificate is in use and reduce the protocol overhead.
This however is not included in this patch to make it easier to
review (in other words, the series at this step should never be
released without the remainder of the series, as it implements an
interim protocol that will be incompatible with the final one).
As such, the documentation update for the protocol is left out of
this step.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-09-15 13:23:20 -07:00
René Scharfe
d318027932 run-command: introduce CHILD_PROCESS_INIT
Most struct child_process variables are cleared using memset first after
declaration.  Provide a macro, CHILD_PROCESS_INIT, that can be used to
initialize them statically instead.  That's shorter, doesn't require a
function call and is slightly more readable (especially given that we
already have STRBUF_INIT, ARGV_ARRAY_INIT etc.).

Helped-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-08-20 09:53:37 -07:00
Junio C Hamano
ad524f834a Merge branch 'jk/misc-fixes-maint'
* jk/misc-fixes-maint:
  apply: avoid possible bogus pointer
  fix memory leak parsing core.commentchar
  transport: fix leaks in refs_from_alternate_cb
  free ref string returned by dwim_ref
  receive-pack: don't copy "dir" parameter
2014-07-28 11:30:41 -07:00
Jeff King
def0697167 transport: fix leaks in refs_from_alternate_cb
The function starts by creating a copy of the static buffer
returned by real_path, but forgets to free it in the error
code paths. We can solve this by jumping to the cleanup code
that is already there.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-24 13:57:50 -07:00
Junio C Hamano
955d7be808 Merge branch 'ta/string-list-init'
* ta/string-list-init:
  replace memset with string-list initializers
  string-list: add string_list initializer helper function
2014-07-23 11:35:54 -07:00
Tanay Abhra
f93d7c6fa0 replace memset with string-list initializers
Using memset and then manually setting values of the string-list
members is not future proof as the internal representation of
string-list may change any time.
Use `string_list_init()` or STRING_LIST_INIT_* macros instead of
memset.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-21 10:23:44 -07:00
René Scharfe
e929f515fa transport: simplify fetch_objs_via_rsync() using argv_array
Use the existing argv_array member instead of building the arguments
list using a string array and a strbuf.  This way we don't need magic
number constants and allocations are cleaned up for us automatically
by run_command().

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-18 11:15:23 -07:00
Jeff King
cf4fff579e refactor skip_prefix to return a boolean
The skip_prefix() function returns a pointer to the content
past the prefix, or NULL if the prefix was not found. While
this is nice and simple, in practice it makes it hard to use
for two reasons:

  1. When you want to conditionally skip or keep the string
     as-is, you have to introduce a temporary variable.
     For example:

       tmp = skip_prefix(buf, "foo");
       if (tmp)
	       buf = tmp;

  2. It is verbose to check the outcome in a conditional, as
     you need extra parentheses to silence compiler
     warnings. For example:

       if ((cp = skip_prefix(buf, "foo"))
	       /* do something with cp */

Both of these make it harder to use for long if-chains, and
we tend to use starts_with() instead. However, the first line
of "do something" is often to then skip forward in buf past
the prefix, either using a magic constant or with an extra
strlen(3) (which is generally computed at compile time, but
means we are repeating ourselves).

This patch refactors skip_prefix() to return a simple boolean,
and to provide the pointer value as an out-parameter. If the
prefix is not found, the out-parameter is untouched. This
lets you write:

  if (skip_prefix(arg, "foo ", &arg))
	  do_foo(arg);
  else if (skip_prefix(arg, "bar ", &arg))
	  do_bar(arg);

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-20 10:44:43 -07:00
Jeff King
ba928c13d7 push: detect local refspec errors early
When pushing, we do not even look at our push refspecs until
after we have made contact with the remote receive-pack and
gotten its list of refs. This means that we may go to some
work, including asking the user to log in, before realizing
we have simple errors like "git push origin matser".

We cannot catch all refspec problems, since fully evaluating
the refspecs requires knowing what the remote side has. But
we can do a quick sanity check of the local side and catch a
few simple error cases.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-05 13:23:27 -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
Junio C Hamano
1945e8ac85 Merge branch 'tb/clone-ssh-with-colon-for-port'
Be more careful when parsing remote repository URL given in the
scp-style host:path notation.

* tb/clone-ssh-with-colon-for-port:
  git_connect(): use common return point
  connect.c: refactor url parsing
  git_connect(): refactor the port handling for ssh
  git fetch: support host:/~repo
  t5500: add test cases for diag-url
  git fetch-pack: add --diag-url
  git_connect: factor out discovery of the protocol and its parts
  git_connect: remove artificial limit of a remote command
  t5601: add tests for ssh
  t5601: remove clear_ssh, refactor setup_ssh_wrapper
2013-12-17 12:03:32 -08:00
Nguyễn Thái Ngọc Duy
b016918b2f send-pack: support pushing to a shallow clone
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-10 16:14:18 -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
b06dcd7d68 connect.c: teach get_remote_heads to parse "shallow" lines
No callers pass a non-empty pointer as shallow_points at this
stage. As a result, all clients still refuse to talk to shallow
repository on the other end.

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
13eb4626c4 remote.h: replace struct extra_have_objects with struct sha1_array
The latter can do everything the former can and is used in many more
places.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-10 16:14:15 -08:00
Torsten Bögershausen
c59ab2e52a connect.c: refactor url parsing
Make the function is_local() in transport.c public, rename it into
url_is_local_not_ssh() and use it in both transport.c and connect.c

Use a protocol "local" for URLs for the local file system.

One note about using file:// under Windows:

The (absolute) path on Unix like system typically starts with "/".
When the host is empty, it can be omitted, so that a shell scriptlet
url=file://$pwd
will give a URL like "file:///home/user/repo".

Windows does not have the same concept of a root directory located in "/".
When parsing the URL allow "file://C:/user/repo"
(even if RFC1738 indicates that "file:///C:/user/repo" should be used).

Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-09 14:54:48 -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
20419de969 Merge branch 'jc/transport-do-not-use-connect-twice-in-fetch'
The auto-tag-following code in "git fetch" tries to reuse the same
transport twice when the serving end does not cooperate and does
not give tags that point to commits that are asked for as part of
the primary transfer.  Unfortunately, Git-aware transport helper
interface is not designed to be used more than once, hence this
does not work over smart-http transfer.

* jc/transport-do-not-use-connect-twice-in-fetch:
  builtin/fetch.c: Fix a sparse warning
  fetch: work around "transport-take-over" hack
  fetch: refactor code that fetches leftover tags
  fetch: refactor code that prepares a transport
  fetch: rename file-scope global "transport" to "gtransport"
  t5802: add test for connect helper
2013-09-09 14:50:37 -07:00
Junio C Hamano
b26ed4305f fetch: work around "transport-take-over" hack
A Git-aware "connect" transport allows the "transport_take_over" to
redirect generic transport requests like fetch(), push_refs() and
get_refs_list() to the native Git transport handling methods.  The
take-over process replaces transport->data with a fake data that
these method implementations understand.

While this hack works OK for a single request, it breaks when the
transport needs to make more than one requests.  transport->data
that used to hold necessary information for the specific helper to
work correctly is destroyed during the take-over process.

One codepath that this matters is "git fetch" in auto-follow mode;
when it does not get all the tags that ought to point at the history
it got (which can be determined by looking at the peeled tags in the
initial advertisement) from the primary transfer, it internally
makes a second request to complete the fetch.  Because "take-over"
hack has already destroyed the data necessary to talk to the
transport helper by the time this happens, the second request cannot
make a request to the helper to make another connection to fetch
these additional tags.

Mark such a transport as "cannot_reuse", and use a separate
transport to perform the backfill fetch in order to work around
this breakage.

Note that this problem does not manifest itself when running t5802,
because our upload-pack gives you all the necessary auto-followed
tags during the primary transfer.  You would need to step through
"git fetch" in a debugger, stop immediately after the primary
transfer finishes and writes these auto-followed tags, remove the
tag references and repack/prune the repository to convince the
"find-non-local-tags" procedure that the primary transfer failed to
give us all the necessary tags, and then let it continue, in order
to trigger the bug in the secondary transfer this patch fixes.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-08-07 16:24:30 -07:00
Junio C Hamano
631b5ef219 push --force-with-lease: tie it all together
This teaches the deepest part of the callchain for "git push" (and
"git send-pack") to enforce "the old value of the ref must be this,
otherwise fail this push" (aka "compare-and-swap" / "--lockref").

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-07-22 22:33:21 -07:00
Junio C Hamano
91048a9537 push --force-with-lease: implement logic to populate old_sha1_expect[]
This plugs the push_cas_option data collected by the command line
option parser to the transport system with a new function
apply_push_cas(), which is called after match_push_refs() has
already been called.

At this point, we know which remote we are talking to, and what
remote refs we are going to update, so we can fill in the details
that may have been missing from the command line, such as

 (1) what abbreviated refname the user gave us matches the actual
     refname at the remote; and

 (2) which remote-tracking branch in our local repository to read
     the value of the object to expect at the remote.

to populate the old_sha1_expect[] field of each of the remote ref.
As stated in the documentation, the use of remote-tracking branch
as the default is a tentative one, and we may come up with a better
logic as we gain experience.

Still nobody uses this information, which is the topic of the next
patch.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-07-22 22:18:19 -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
Junio C Hamano
2ddc898bc0 Merge branch 'ph/builtin-srcs-are-in-subdir-these-days'
* ph/builtin-srcs-are-in-subdir-these-days:
  fix "builtin-*" references to be "builtin/*"
2013-06-26 15:07:48 -07:00
Phil Hord
09b7e2204a fix "builtin-*" references to be "builtin/*"
Documentation and some comments still refer to files in builtin/
as 'builtin-*.[cho]'.  Update these to show the correct location.

Signed-off-by: Phil Hord <hordp@cisco.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Assisted-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-06-18 11:05:51 -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