After calling stat_tracking_info, callers often want to
print the name of the upstream branch (in addition to the
tracking count). To do this, they have to access
branch->merge->dst[0] themselves. This is not wrong, as the
return value from stat_tracking_info tells us whether we
have an upstream branch or not. But it is a bit leaky, as we
make an assumption about how it calculated the upstream
name.
Instead, let's add an out-parameter that lets the caller
know the upstream name we found.
As a bonus, we can get rid of the unusual tri-state return
from the function. We no longer need to use it to
differentiate between "no tracking config" and "tracking ref
does not exist" (since you can check the upstream_name for
that), so we can just use the usual 0/-1 convention for
success/error.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The error-diagnosis logic in branch_get_upstream was copied
straight from sha1_name.c in the previous commit. However,
because we check all error cases and upfront and then later
diagnose them, the logic is a bit tangled. In particular:
- if branch->merge[0] is NULL, we may end up dereferencing
it for an error message (in practice, it should never be
NULL, so this is probably not a triggerable bug).
- We may enter the code path because branch->merge[0]->dst
is NULL, but we then start our error diagnosis by
checking whether our local branch exists. But that is
only relevant to diagnosing missing merge config, not a
missing tracking ref; our diagnosis may hide the real
problem.
Instead, let's just use a sequence of "if" blocks to check
for each error type, diagnose it, and return NULL.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When the previous commit introduced the branch_get_upstream
helper, there was one call-site that could not be converted:
the one in sha1_name.c, which gives detailed error messages
for each possible failure.
Let's teach the helper to optionally report these specific
errors. This lets us convert another callsite, and means we
can use the helper in other locations that want to give the
same error messages.
The logic and error messages come straight from sha1_name.c,
with the exception that we start each error with a lowercase
letter, as is our usual style (note that a few tests need
updated as a result).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
All of the information needed to find the @{upstream} of a
branch is included in the branch struct, but callers have to
navigate a series of possible-NULL values to get there.
Let's wrap that logic up in an easy-to-read helper.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Before the previous commit, we had to make sure that
read_config() was called before entering remote_get_1,
because we needed to pass pushremote_name by value. But now
that we pass a function, we can let remote_get_1 handle
loading the config itself, turning our wrappers into true
one-liners.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When remote.c loads its config, it records the
branch.*.pushremote for the current branch along with the
global remote.pushDefault value, and then binds them into a
single value: the default push for the current branch. We
then pass this value (which may be NULL) to remote_get_1
when looking up a remote for push.
This has a few downsides:
1. It's confusing. The early-binding of the "current
value" led to bugs like the one fixed by 98b406f
(remote: handle pushremote config in any order,
2014-02-24). And the fact that pushremotes fall back to
ordinary remotes is not explicit at all; it happens
because remote_get_1 cannot tell the difference between
"we are not asking for the push remote" and "there is
no push remote configured".
2. It throws away intermediate data. After read_config()
finishes, we have no idea what the value of
remote.pushDefault was, because the string has been
overwritten by the current branch's
branch.*.pushremote.
3. It doesn't record other data. We don't note the
branch.*.pushremote value for anything but the current
branch.
Let's make this more like the fetch-remote config. We'll
record the pushremote for each branch, and then explicitly
compute the correct remote for the current branch at the
time of reading.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We'll want to use this logic as a fallback when looking up
the pushremote, so let's pull it out into its own function.
We don't technically need to make this available outside of
remote.c, but doing so will provide a consistent API with
pushremote_for_branch, which we will add later.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we create each branch struct, we fill in the
"remote_name" field from the config, and then fill in the
actual "remote" field (with a "struct remote") based on that
name. However, it turns out that nobody really cares about
the latter field. The only two sites that access it at all
are:
1. git-merge, which uses it to notice when the branch does
not have a remote defined. But we can easily replace this
with looking at remote_name instead.
2. remote.c itself, when setting up the @{upstream} merge
config. But we don't need to save the "remote" in the
"struct branch" for that; we can just look it up for
the duration of the operation.
So there is no need to have both fields; they are redundant
with each other (the struct remote contains the name, or you
can look up the struct from the name). It would be nice to
simplify this, especially as we are going to add matching
pushremote config in a future patch (and it would be nice to
keep them consistent).
So which one do we keep and which one do we get rid of?
If we had a lot of callers accessing the struct, it would be
more efficient to keep it (since you have to do a lookup to
go from the name to the struct, but not vice versa). But we
don't have a lot of callers; we have exactly one, so
efficiency doesn't matter. We can decide this based on
simplicity and readability.
And the meaning of the struct value is somewhat unclear. Is
it always the remote matching remote_name? If remote_name is
NULL (i.e., no per-branch config), does the struct fall back
to the "origin" remote, or is it also NULL? These questions
will get even more tricky with pushremotes, whose fallback
behavior is more complicated. So let's just store the name,
which pretty clearly represents the branch.*.remote config.
Any lookup or fallback behavior can then be implemented in
helper functions.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we call branch_get() to lookup or create a "struct
branch", we make sure the "merge" field is filled in so that
callers can access it. But the conditions under which we do
so are a little confusing, and can lead to two funny
situations:
1. If there's no branch.*.remote config, we cannot provide
branch->merge (because it is really just an application
of branch.*.merge to our remote's refspecs). But
branch->merge_nr may be non-zero, leading callers to be
believe they can access branch->merge (e.g., in
branch_merge_matches and elsewhere).
It doesn't look like this can cause a segfault in
practice, as most code paths dealing with merge config
will bail early if there is no remote defined. But it's
a bit of a dangerous construct.
We can fix this by setting merge_nr to "0" explicitly
when we realize that we have no merge config. Note that
merge_nr also counts the "merge_name" fields (which we
_do_ have; that's how merge_nr got incremented), so we
will "lose" access to them, in the sense that we forget
how many we had. But no callers actually care; we use
merge_name only while iteratively reading the config,
and then convert it to the final "merge" form the first
time somebody calls branch_get().
2. We set up the "merge" field every time branch_get is
called, even if it has already been done. This leaks
memory.
It's not a big deal in practice, since most code paths
will access only one branch, or perhaps each branch
only one time. But if you want to be pathological, you
can leak arbitrary memory with:
yes @{upstream} | head -1000 | git rev-list --stdin
We can fix this by skipping setup when branch->merge is
already non-NULL.
In addition to those two fixes, this patch pushes the "do we
need to setup merge?" logic down into set_merge, where it is
a bit easier to follow.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we read the remote config from disk, we update a
default_remote_name variable if we see branch.*.remote
config for the current branch. This isn't wrong, or even all
that complicated, but it is a bit simpler (because it
reduces our overall state) to just lazily compute the
default when we need it.
The ulterior motive here is that the push config uses a
similar structure, and _is_ much more complicated as a
result. That will be simplified in a future patch, and it's
more readable if the logic for remotes and push-remotes
matches.
Note that we also used default_remote_name as a signal that
the remote config has been loaded; after this patch, we now
use an explicit flag.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This replaces "x ? xstrdup(x) : NULL" with xstrdup_or_null(x).
The change is fairly mechanical, with the exception of
resolve_refdup, which can eliminate a temporary variable.
There are still a few hits grepping for "?.*xstrdup", but
these are of slightly different forms and cannot be
converted (e.g., "x ? xstrdup(x->foo) : NULL").
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The new name is more consistent with the names of other
string_list-related functions.
Suggested-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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>
When checking out a branch that is set to build on top of another
branch (often, a remote-tracking branch), "git checkout" reports how
your work relates to the other branch, e.g.
Your branch is behind 'origin/master', and can be fast-forwarded.
Back when this feature was introduced, this was only done for
branches that build on remote-tracking branches, but 5e6e2b48 (Make
local branches behave like remote branches when --tracked,
2009-04-01) added support to give the same report for branches that
build on other local branches (i.e. branches whose branch.*.remote
variables are set to '.'). Unlike the support for the branches
building on remote-tracking branches, however, this did not take
into account the fact that branch.*.merge configuration is allowed
to record a shortened branch name.
When branch.*.merge is set to 'master' (not 'refs/heads/master'),
i.e. "my branch builds on the local 'master' branch", this caused
"git checkout" to report:
Your branch is based on 'master', but the upstream is gone.
The upstream is our repository and is definitely not gone, so this
output is nonsense.
The fix is fairly obvious; just like the branch name is DWIMed when
"git pull" merges from the 'master' branch without complaint on such
a branch, the name of the branch the current branch builds upon
needs to be DWIMed the same way.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Make the code simpler and shorter by avoiding repetitive use of
string length variables and leaving memory allocation to strbuf
functions.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Even the documentation tells us:
You should check if it returns any error (non-zero return
code) and if it does not, you can start using get_revision()
to do the iteration.
In preparation for this commit, I grepped all occurrences of
prepare_revision_walk and added error messages, when there were none.
Signed-off-by: Stefan Beller <stefanbeller@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Remotes are stored as an array, so looking one up or adding one without
duplication is an O(n) operation. Reading an entire config file full of
remotes is O(n^2) in the number of remotes. For a repository with tens of
thousands of remotes, the running time can hit multiple minutes.
Hash tables are way faster. So we add a hashmap from remote name to
struct remote and use it for all lookups. The time to add a new remote to
a repo that already has 50,000 remotes drops from ~2 minutes to < 1
second.
We retain the old array of remotes so iterators proceed in config-file
order.
Signed-off-by: Patrick Reynolds <patrick.reynolds@github.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It's a common idiom to match a prefix and then skip past it
with strlen, like:
if (starts_with(foo, "bar"))
foo += strlen("bar");
This avoids magic numbers, but means we have to repeat the
string (and there is no compiler check that we didn't make a
typo in one of the strings).
We can use skip_prefix to handle this case without repeating
ourselves.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In many parts of the code, we do an ugly and error-prone
malloc like:
const char *fmt = "something %s";
buf = xmalloc(strlen(foo) + 10 + 1);
sprintf(buf, fmt, foo);
This makes the code brittle, and if we ever get the
allocation wrong, is a potential heap overflow. Let's
instead favor xstrfmt, which handles the allocation
automatically, and makes the code shorter and more readable.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert three cases of checking for a constant prefix using memcmp() to
starts_with(). This way there is no need for magic string length
constants and we avoid running over the end of the string should it be
shorter than the prefix.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
xcalloc() takes two arguments: the number of elements and their size.
parse_refspec_internal passes the arguments in reverse order, passing the
size of a refspec, followed by the number to allocate.
Rearrange them so they are in the correct order.
Signed-off-by: Brian Gesiak <modocache@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We need to consider that a remote-tracking branch may match more than
one rhs of a fetch refspec. In such a case, it is not enough to stop at
the first match but look at all of the matches in order to determine
whether a head is stale.
To this goal, introduce a variant of query_refspecs which returns all of
the matching refspecs and loop over those answers to check for
staleness.
Signed-off-by: Carlos Martín Nieto <cmn@elego.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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>
The match_explicit_lhs function has all of the logic
necessary to verify the refspecs without actually doing any
work. This patch lets callers pass a NULL "match" pointer to
indicate they want a "verify only" operation.
For the most part, we just need to avoid writing to the NULL
pointer. However, we also have to refactor the
try_explicit_object_name sub-function; it indicates success by
allocating and returning a new ref. Instead, we give it an
"out" parameter for the match and return a numeric status.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In preparation for being able to check the left-hand side of
our push refspecs separately, this pulls the examination of
them out into its own function. There should be no behavior
change.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The remote we push can be defined either by
remote.pushdefault or by branch.*.pushremote for the current
branch. The order in which they appear in the config file
should not matter to precedence (which should be to prefer
the branch-specific config).
The current code parses the config linearly and uses a
single string to store both values, overwriting any
previous value. Thus, config like:
[branch "master"]
pushremote = foo
[remote]
pushdefault = bar
erroneously ends up pushing to "bar" from the master branch.
We can fix this by storing both values and resolving the
correct value after all config is read.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We used to use two separate rules for the normal ref resolution
dwimming and dwimming done to decide which remote ref to grab. The
third parameter to refname_match() selected which rules to use.
When these two rules were harmonized in
2011-11-04 dd621df9cd refs DWIMmery: use the same rule for both "git fetch" and others
, ref_fetch_rules was #defined to avoid potential breakages for
in-flight topics.
It is now safe to remove the backwards-compatibility code, so remove
refname_match()'s third parameter, make ref_rev_parse_rules private to
refs.c, and remove ref_fetch_rules entirely.
Suggested-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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>
Since f2690487 (fetch: opportunistically update tracking refs,
2013-05-11), we stopped taking a non-storing refspec given on the
command line of "git fetch" literally, and instead started mapping
it via remote.$name.fetch refspecs. This allows
$ git fetch origin master
from the 'origin' repository, which is configured with
[remote "origin"]
fetch = +refs/heads/*:refs/remotes/origin/*
to update refs/remotes/origin/master with the result, as if the
command line were
$ git fetch origin +master:refs/remotes/origin/master
to reduce surprises and improve usability. Before that change, a
refspec on the command line without a colon was only to fetch the
history and leave the result in FETCH_HEAD, without updating the
remote-tracking branches.
When you are simulating a fetch from you by your mothership with a
push by you into your mothership, instead of having:
[remote "satellite"]
fetch = +refs/heads/*:refs/remotes/satellite/*
on the mothership repository and running:
mothership$ git fetch satellite
you would have:
[remote "mothership"]
push = +refs/heads/*:refs/remotes/satellite/*
on your satellite machine, and run:
satellite$ git push mothership
Because we so far did not make the corresponding change to the push
side, this command:
satellite$ git push mothership master
does _not_ allow you on the satellite to only push 'master' out but
still to the usual destination (i.e. refs/remotes/satellite/master).
Implement the logic to map an unqualified refspec given on the
command line via the remote.$name.push refspec. This will bring a
bit more symmetry between "fetch" and "push".
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If we find two refspecs that want to update the same local reference,
emit an error message that is more informative based on whether one of
the conflicting refspecs is an opportunistic update during a fetch
with explicit command-line refspecs. And especially, do not die if an
opportunistic reference update conflicts with an express wish of the
user; rather, just emit a warning and skip the opportunistic reference
update.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the loop body into the more straightforward
* remove item from the front of the old list
* if necessary, add it to the tail of the new list
and return a pointer to the new list (even though it is currently
always the same as the input argument, because the first element in
the list is currently never deleted).
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The old code called string_list_lookup(), and if that failed called
string_list_insert(), thus doing the bisection search through the
string list twice in the latter code path.
Instead, just call string_list_insert() right away. If an entry for
that peer reference name already existed, then its util pointer is
always non-NULL.
Of course this doesn't change the fact that the repeated
string_list_insert() calls make the function scale like O(N^2) if the
input reference list is not already approximately sorted.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The old code could leak *expn_name if match_name_with_pattern()
succeeded but ignore_symref_update() returned true. So make sure that
*expn_name is freed in any case.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Our default_remote_name starts at "origin", but may be
overridden by the config file. In the former case, we
allocate a new string, but in the latter case, we point to
the remote name in an existing "struct branch".
This gives the variable inconsistent free() semantics (we
are sometimes responsible for freeing the string and
sometimes pointing to somebody else's storage), and causes a
small leak when the allocated string is overridden by
config.
We can fix both by simply dropping the extra copy and
pointing to the string literal.
Noticed-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In order to see what the current branch is tracking, one way is using
"git branch -v -v", but branches other than the current are also
reported. Another way is using "git status", such as:
$ git status
# On branch master
# Your branch is ahead of 'origin/master' by 1 commit.
...
But this will not work if there is no change between the current
branch and its upstream. Always report upstream tracking info
even if there is no difference, so that "git status" is consistent
for checking tracking info for current branch. E.g.
$ git status
# On branch feature1
# Your branch is up-to-date with 'github/feature1'.
...
$ git status -bs
## feature1...github/feature1
...
$ git checkout feature1
Already on 'feature1'
Your branch is up-to-date with 'github/feature1'.
...
Also add some test cases in t6040.
Signed-off-by: Jiang Xin <worldhello.net@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Command "git branch -vv" will report tracking branches, but invalid
tracking branches are also reported. This is because the function
stat_tracking_info() can not distinguish invalid tracking branch
from other cases which it would not like to report, such as
there is no upstream settings at all, or nothing is changed between
one branch and its upstream.
Junio suggested missing upstream should be reported [1] like:
$ git branch -v -v
master e67ac84 initial
* topic 3fc0f2a [topicbase: gone] topic
$ git status
# On branch topic
# Your branch is based on 'topicbase', but the upstream is gone.
# (use "git branch --unset-upstream" to fixup)
...
$ git status -b -s
## topic...topicbase [gone]
...
In order to do like that, we need to distinguish these three cases
(i.e. no tracking, with configured but no longer valid tracking, and
with tracking) in function stat_tracking_info(). So the refactored
function stat_tracking_info() has three return values: -1 (with "gone"
base), 0 (no base), and 1 (with base).
If the caller does not like to report tracking info when nothing
changed between the branch and its upstream, simply checks if
num_theirs and num_ours are both 0.
[1]: http://thread.gmane.org/gmane.comp.version-control.git/231830/focus=232288
Suggested-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Jiang Xin <worldhello.net@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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>
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>
Update "git push" and "git send-pack" to parse this commnd line
option.
The intended sematics is:
* "--force-with-lease" alone, without specifying the details, will
protect _all_ remote refs that are going to be updated by
requiring their current value to be the same as some reasonable
default, unless otherwise specified;
* "--force-with-lease=refname", without specifying the expected
value, will protect that refname, if it is going to be updated,
by requiring its current value to be the same as some reasonable
default.
* "--force-with-lease=refname:value" will protect that refname, if
it is going to be updated, by requiring its current value to be
the same as the specified value; and
* "--no-force-with-lease" will cancel all the previous --force-with-lease on the
command line.
For now, "some reasonable default" is tentatively defined as "the
value of the remote-tracking branch we have for the ref of the
remote being updated", and it is an error if we do not have such a
remote-tracking branch. But this is known to be fragile, its use is
not yet recommended, and hopefully we will find more reasonable
default as we gain experience with this feature. The manual marks
the feature as experimental unless the expected value is specified
explicitly for this reason.
Because the command line options are parsed _before_ we know which
remote we are pushing to, there needs further processing to the
parsed data after we instantiate the transport object to:
* expand "refname" given by the user to a full refname to be
matched with the list of "struct ref" used in match_push_refs()
and set_ref_status_for_push(); and
* learning the actual local ref that is the remote-tracking branch
for the specified remote ref.
Further, some processing need to be deferred until we find the set
of remote refs and match_push_refs() returns in order to find the
ones that need to be checked after explicit ones have been processed
for "--force-with-lease" (no specific details).
These post-processing will be the topic of the next patch.
This option was originally called "cas" (for "compare and swap"),
the name which nobody liked because it was too technical. The
second attempt called it "lockref" (because it is conceptually like
pushing after taking a lock) but the word "lock" was hated because
it implied that it may reject push by others, which is not the way
this option works. This round calls it "force-with-lease". You
assume you took the lease on the ref when you fetched to decide what
the rebased history should be, and you can push back only if the
lease has not been broken.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Without "git fetch --prune", remote-tracking branches for a branch
the other side already has removed will stay forever. Some people
want to always run "git fetch --prune".
To accommodate users who want to either prune always or when fetching
from a particular remote, add two new configuration variables
"fetch.prune" and "remote.<name>.prune":
- "fetch.prune" allows to enable prune for all fetch operations.
- "remote.<name>.prune" allows to change the behaviour per remote.
The latter will naturally override the former, and the --[no-]prune
option from the command line will override the configured default.
Since --prune is a potentially destructive operation (Git doesn't
keep reflogs for deleted references yet), we don't want to prune
without users consent, so this configuration will not be on by
default.
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Michael Schubert <mschub@elegosoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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>
When pushing using a matching refspec or a pattern refspec, each ref
in the local repository must be paired with a ref advertised by the
remote server. This is accomplished by using the refspec to transform
the name of the local ref into the name it should have in the remote
repository, and then performing a linear search through the list of
remote refs to see if the remote ref was advertised by the remote
system.
Each of these lookups has O(n) complexity and makes match_push_refs()
be an O(m*n) operation, where m is the number of local refs and n is
the number of remote refs. If there are many refs 100,000+, then this
ref matching can take a significant amount of time. Let's prepare an
index of the remote refs to allow searching in O(log n) time and
reduce the complexity of match_push_refs() to O(m log n).
We prepare the index lazily so that it is only created when necessary.
So, there should be no impact when _not_ using a matching or pattern
refspec, i.e. when pushing using only explicit refspecs.
Dry-run push of a repository with 121,913 local and remote refs:
before after
real 1m40.582s 0m0.804s
user 1m39.914s 0m0.515s
sys 0m0.125s 0m0.106s
The creation of the index has overhead. So, if there are very few
local refs, then it could take longer to create the index than it
would have taken to just perform n linear lookups into the remote
ref space. Using the index should provide some improvement when
the number of local refs is roughly greater than the log of the
number of remote refs (i.e. m >= log n). The pathological case is
when there is a single local ref and very many remote refs.
Dry-run push of a repository with 121,913 remote refs and a single
local ref:
before after
real 0m0.525s 0m0.566s
user 0m0.243s 0m0.279s
sys 0m0.075s 0m0.099s
Using an index takes 41 ms longer, or roughly 7.8% longer.
Jeff King measured a no-op push of a single ref into a remote repo
with 370,000 refs:
before after
real 0m1.087s 0m1.156s
user 0m1.344s 0m1.412s
sys 0m0.288s 0m0.284s
Using an index takes 69 ms longer, or roughly 6.3% longer.
None of the measurements above required transferring any objects to
the remote repository. If the push required transferring objects and
updating the refs in the remote repository, the impact of preparing
the search index would be even smaller.
A similar operation is performed in the reverse direction when pruning
using a matching or pattern refspec. Let's avoid O(m*n) behavior in
the same way by lazily preparing an index on the local refs.
Signed-off-by: Brandon Casey <drafnel@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The first line of the function checks that the remote-name contains a
slash ('/'), and sets the "slash" variable accordingly. The only caller
of read_branches_file() is remote_get_1(); the calling codepath is
guarded by valid_remote_nick(), which checks that the remote does not
contain a slash. Therefore, the "slash" variable can never be set:
remove the dead code that assumes otherwise.
Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King