clear parsed flag when we free tree buffers

Many code paths will free a tree object's buffer and set it
to NULL after finishing with it in order to keep memory
usage down during a traversal. However, out of 8 sites that
do this, only one actually unsets the "parsed" flag back.
Those sites that don't are setting a trap for later users of
the tree object; even after calling parse_tree, the buffer
will remain NULL, causing potential segfaults.

It is not known whether this is triggerable in the current
code. Most commands do not do an in-memory traversal
followed by actually using the objects again. However, it
does not hurt to be safe for future callers.

In most cases, we can abstract this out to a
"free_tree_buffer" helper. However, there are two
exceptions:

  1. The fsck code relies on the parsed flag to know that we
     were able to parse the object at one point. We can
     switch this to using a flag in the "flags" field.

  2. The index-pack code sets the buffer to NULL but does
     not free it (it is freed by a caller). We should still
     unset the parsed flag here, but we cannot use our
     helper, as we do not want to free the buffer.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
pull: require choice between rebase/merge on non-fast-forward pull

Because it is so easy to let Git handle automatically a trivial
merge with "git pull", a person who is new to Git may not realize
that the project s/he is interacting with may prefer a "rebase"
workflow.

Add a safety valve to fail "git pull" that does not explicitly
specify what branch from which repository to integrate your history
with, when it is neither a fast-forward or "already up-to-date",
until/unless the user expressed her preference between the two ways
of integration.

This can be an irritating backward incompatible change for old
timers, but it can be a one time irritation by doing:

    git config --global pull.rebase false

once to say "I will always --merge", and they'd not even notice.

    http://thread.gmane.org/gmane.comp.version-control.git/225146/focus=225326

for a full discussion.

Helped-by: John Keeping <john@keeping.me.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
git p4 test: sanitize P4CHARSET

In the tests, p4d is started without using "internationalized
mode".  Make sure this environment variable is unset, otherwise
a mis-matched user setting would break the tests.  The error
message would be "Unicode clients require a unicode enabled server."

[pw: use unset, add commit text]

Signed-off-by: Kazuki Saitoh <ksaitoh560@gmail.com>
Signed-off-by: Pete Wyckoff <pw@padd.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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>
config: properly range-check integer values

When we look at a config value as an integer using the
git_config_int function, we carefully range-check the value
we get and complain if it is out of our range. But the range
we compare to is that of a "long", which we then cast to an
"int" in the function's return value. This means that on
systems where "int" and "long" have different sizes (e.g.,
LP64 systems), we may pass the range check, but then return
nonsense by truncating the value as we cast it to an int.

We can solve this by converting git_parse_long into
git_parse_int, and range-checking the "int" range. Nobody
actually cared that we used a "long" internally, since the
result was truncated anyway, and there were no other callers
of git_parse_long.

Of the existing callers, all of them expect small-ish values
that are fine for an "int", and should not be impacted
except when nonsense is fed to them. The one arguable
exception is http.lowSpeedLimit, which is given in bytes per
second, and is fed to curl as a long. However, nobody is
likely to consider 2GB/sec as "low speed", and even if they
did, the new behavior is much better (it barfs and complains
rather than considering the value negative and silently
ignoring it).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
teach git-config to output large integers

Internally we use "unsigned long" to represent large config
values like packed window memory sizes, packfile size
limits, etc.  On 32-bit systems, this limits these config
options to 4G (and we detect and complain about overflow).
On 64-bit systems, they get the full 64-bit range.

However, there is no way for script callers of git-config to
see the numeric values (they cannot treat them as pure
strings, since they would want git-config to process "3g"
into "3221225472").

This patch teaches git-config a "--ulong" type that can
output these unsigned long values, allowing scripts to
examine the values as the internal code would.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --no-index: clarify operation when not inside a repository

Clarify documentation for "diff --no-index".  State that when not
inside a repository, --no-index is implied and two arguments are
mandatory.

Clarify error message from diff-no-index to inform user that CWD is
not inside a repository and thus two arguments are mandatory.

Signed-off-by: Dale Worley <worley@ariadne.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
test-sha1: add a binary output mode

The test-sha1 helper program will run our internal sha1
routines over its input and output the 40-byte hex sha1.
Sometimes, however, it is useful to have the binary 20-byte
sha1 (and it's a pain to convert back in the shell). Let's
add a "-b" option to output the binary version.

Signed-off-by: Jeff King <peff@peff.net>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
commit: search author pattern against mailmap

"git commit --author=$name" sets the author to one whose name
matches the given string from existing commits, when $name is not in
the "Name <e-mail>" format. However, it does not honor the mailmap
to use the canonical name for the author found this way.

Fix it by telling the logic to find a matching existing author to
honor the mailmap, and use the name and email after applying the
mailmap.

Signed-off-by: Antoine Pelisse <apelisse@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
sha1-lookup: handle duplicate keys with GIT_USE_LOOKUP

The sha1_entry_pos function tries to be smart about
selecting the middle of a range for its binary search by
looking at the value differences between the "lo" and "hi"
constraints. However, it is unable to cope with entries with
duplicate keys in the sorted list.

We may hit a point in the search where both our "lo" and
"hi" point to the same key. In this case, the range of
values between our endpoints is 0, and trying to scale the
difference between our key and the endpoints over that range
is undefined (i.e., divide by zero). The current code
catches this with an "assert(lov < hiv)".

Moreover, after seeing that the first 20 byte of the key are
the same, we will try to establish a value from the 21st
byte. Which is nonsensical.

Instead, we can detect the case that we are in a run of
duplicates, and simply do a final comparison against any one
of them (since they are all the same, it does not matter
which). If the keys match, we have found our entry (or one
of them, anyway).  If not, then we know that we do not need
to look further, as we must be in a run of the duplicate
key.

Signed-off-by: Jeff King <peff@peff.net>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
add tests for indexing packs with delta cycles

If we receive a broken or malicious pack from a remote, we
will feed it to index-pack. As index-pack processes the
objects as a stream, reconstructing and hashing each object
to get its name, it is not very susceptible to doing the
wrong with bad data (it simply notices that the data is
bogus and aborts).

However, one question raised on the list is whether it could
be susceptible to problems during the delta-resolution
phase. In particular, can a cycle in the packfile deltas
cause us to go into an infinite loop or cause any other
problem?

The answer is no.

We cannot have a cycle of delta-base offsets, because they
go only in one direction (the OFS_DELTA object mentions its
base by an offset towards the beginning of the file, and we
explicitly reject negative offsets).

We can have a cycle of REF_DELTA objects, which refer to
base objects by sha1 name. However, index-pack does not know
these sha1 names ahead of time; it has to reconstruct the
objects to get their names, and it cannot do so if there is
a delta cycle (in other words, it does not even realize
there is a cycle, but only that there are items that cannot
be resolved).

Even though we can reason out that index-pack should handle
this fine, let's add a few tests to make sure it behaves
correctly.

Signed-off-by: Jeff King <peff@peff.net>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
test index-pack on packs with recoverable delta cycles

The previous commit added tests to show that index-pack
correctly bails in unrecoverable situations. There are some
situations where the data could be recovered, but it is not
currently:

  1. If we can break the cycle using an object from another
     pack via --fix-thin.

  2. If we can break the cycle using a duplicate of one of
     the objects found in the same pack.

Note that neither of these is particularly high priority; a
delta cycle within a pack should never occur, and we have no
record of even a buggy git implementation creating such a
pack.

However, it's worth adding these tests for two reasons. One,
to document that we do not currently handle the situation,
even though it is possible. And two, to exercise the code
that runs in this situation; even though it fails, by
running it we can confirm that index-pack detects the
situation and aborts, and does not misbehave (e.g., by
following the cycle in an infinite loop).

In both cases, we hit an assert that aborts index-pack.

Signed-off-by: Jeff King <peff@peff.net>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Make test "using invalid commit with -C" more strict

In the test 'using invalid commit with -C' git-commit would have failed
even if the -C option had been given the correct commit, as there was
nothing to commit. Pass --allow-empty to make sure it would make a commit,
were there no issues with the argument given to the -C option.

Signed-off-by: Kacper Kornet <draenog@pld-linux.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
add -i test: use skip_all instead of repeated PERL prerequisite

It is too easy to forget to add the PERL prerequisite for new
"add -i" tests, especially given that many people do not test with
NO_PERL so the missing prereq is not always noticed quickly.

The test had used the skip_all mechanism since 1b19ccd2 (2009-04-03)
but switched to explicit PERL prereqs in f0459319 (2010-10-13) in hope
of helping people see how many tests were skipped, perhaps to motivate
them to tweak their platform or tests to improve test coverage.  That
didn't pan out much in practice, so let's move back to the simpler
skip_all method.

Reported-by: Kacper Kornet <draenog@pld-linux.org>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
t/t7106-reset-unborn-branch.sh: Add PERL prerequisite

The test 'reset -p' uses git-reset -p, so it depends on the perl code.

Signed-off-by: Kacper Kornet <draenog@pld-linux.org>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
reset test: modernize style

Avoid command substitution and pipes to ensure that the exit status
from each git command is tested (and in particular that any segfaults
are caught).

Maintain the test setup (no commits, one file named "a", another named
"b") even after the last test, to make it easier to rearrange tests or
add new tests after the last in the future.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
branch: report invalid tracking branch as gone

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>
status: always show tracking branch even no change

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>
Set core.precomposeunicode to true on e.g. HFS+

When core.precomposeunicode was introduced in 76759c7d,
it was set to false on a unicode decomposing file system like HFS+
to be compatible with older versions of Git.

The Mac OS users need to find out that this configuration exist
and change it manually from false to true.

A smoother workflow can be achieved,
so set core.precomposeunicode to true on a decomposing file system.

Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Call it "Git User Manual" and remove reference to very old Git version

Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Thomas Ackermann <th.acker@arcor.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>