apply: do not leak patches and fragments

In the while loop inside apply_patch, patch and fragments are
dynamically allocated with a calloc. However, only unused patches
are actually freed and the rest are left to leak. Since a list is
actively built up consisting of the used patches, they can simply be
iterated and freed at the end of the function.

In addition, the text in fragments were not freed, primarily because
they mostly point into a patch text that is freed as a whole. But
there are some cases where new piece of memory is allocated and
pointed by a fragment (namely, when handling a binary patch).

Introduce a free_patch bitfield to mark each fragment if its text
needs to be freed, and free patches, fragments and fragment text
that need to be freed when we are done with the input.

Signed-off-by: Jared Hance <jaredhance@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
fmt-merge-msg: show those involved in a merged series

As we already walk the history of the branch that gets merged to
come up with a short log, let's label it with names of the primary
authors, so that the user who summarizes the merge can easily give
credit to them in the log message.

Also infer the names of "lieutents" to help integrators at higher
level of the food-chain to give credit to them, by counting:

 * The committer of the 'tip' commit that is merged
 * The committer of merge commits that are merged

Often the first one gives the owner of the history being pulled, but
his last pull from his sublieutenants may have been a fast-forward,
in which case the first one would not be.  The latter rule will
count the integrator of the history, so together it might be a
reasonable heuristics.

There are two special cases:

 - The "author" credit is omitted when the series is written solely
   by the same author who is making the merge. The name can be seen
   on the "Author" line of the "git log" output to view the log
   message anyway.

 - The "lieutenant" credit is omitted when there is only one key
   committer in the merged branch and it is the committer who is
   making the merge. Typically this applies to the case where the
   developer merges his own branch.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
push: Provide situational hints for non-fast-forward errors

Pushing a non-fast-forward update to a remote repository will result in
an error, but the hint text doesn't provide the correct resolution in
every case. Give better resolution advice in three push scenarios:

1) If you push your current branch and it triggers a non-fast-forward
error, you should merge remote changes with 'git pull' before pushing
again.

2) If you push to a shared repository others push to, and your local
tracking branches are not kept up to date, the 'matching refs' default
will generate non-fast-forward errors on outdated branches. If this is
your workflow, the 'matching refs' default is not for you. Consider
setting the 'push.default' configuration variable to 'current' or
'upstream' to ensure only your current branch is pushed.

3) If you explicitly specify a ref that is not your current branch or
push matching branches with ':', you will generate a non-fast-forward
error if any pushed branch tip is out of date. You should checkout the
offending branch and merge remote changes before pushing again.

Teach transport.c to recognize these scenarios and configure push.c
to hint for them. If 'git push's default behavior changes or we
discover more scenarios, extension is easy. Standardize on the
advice API and add three new advice variables, 'pushNonFFCurrent',
'pushNonFFDefault', and 'pushNonFFMatching'. Setting any of these
to 'false' will disable their affiliated advice. Setting
'pushNonFastForward' to false will disable all three, thus preserving the
config option for users who already set it, but guaranteeing new
users won't disable push advice accidentally.

Based-on-patch-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Christopher Tiwald <christiwald@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
log --graph --stat: three-dash separator should come after graph lines

Output from "git log --graph --stat -p" emits the three-dash separator
line before the graph that shows ancestry lines.  The separator should
come after the ancestry lines just like all the other output.

Signed-off-by: Lucian Poston <lucian.poston@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
log --graph: fix break in graph lines

Output from "git log --graph --stat -p" broke the ancestry graph lines
with a single empty line between the diffstat and the patch.

Signed-off-by: Lucian Poston <lucian.poston@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
t4202: add test for "log --graph --stat -p" separator lines

Add tests to make sure that the three-dash separator lines appear
after the graph ancestry lines, and also the graph ancestry lines
are not broken between the diffstat and the patch.

Signed-off-by: Lucian Poston <lucian.poston@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
clean up struct ref's nonfastforward field

Each ref structure contains a "nonfastforward" field which
is set during push to show whether the ref rewound history.
Originally this was a single bit, but it was changed in
f25950f (push: Provide situational hints for non-fast-forward
errors) to an enum differentiating a non-ff of the current
branch versus another branch.

However, we never actually set the member according to the
enum values, nor did we ever read it expecting anything but
a boolean value. But we did use the side effect of declaring
the enum constants to store those values in a totally
different integer variable. The code as-is isn't buggy, but
the enum declaration inside "struct ref" is somewhat
misleading.

Let's convert nonfastforward back into a single bit, and
then define the NON_FF_* constants closer to where they
would be used (they are returned via the "int *nonfastforward"
parameter to transport_push, so we can define them there).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
apply: rename free_patch() to free_patch_list()

As that is the only logical name for a function that walks a list
and frees each element on it.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
apply: free patch->{def,old,new}_name fields

These were all allocated in the heap by parsing the header parts of the
patch, but we did not bother to free them.  Some used to share the memory
(e.g. copying def_name to old_name) so this is not just the matter of
adding three calls to free().

Signed-off-by: Junio C Hamano <gitster@pobox.com>
apply: release memory for fn_table

The fn_table is used to record the result of earlier patch application in
case a hand-crafted input file contains multiple patches to the same file.
Both its string key (filename) and the contents are borrowed from "struct
patch" that represents the previous application in the same apply_patch()
call, and they do not leak, but the table itself was not freed properly.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
apply: free patch->result

This is by far the largest piece of data, much larger than the patch and
fragment structures or the three name fields in the patch structure.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
am -3: list the paths that needed 3-way fallback

When applying a patch that was based on an older release with "am -3", I
often wonder changes to which files need to be reviewed with extra care to
spot mismerges, but there is no good indication.

The paths that needed 3-way fallback can easily be obtained by comparing
the synthesized (partial) base tree and the current HEAD and noticing only
additions and modifications (removals only show the sparseness of the fake
ancestor tree, which is not useful information at all).  List them in the
usual --name-status format.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
am: support --include option

am supports a number of pass-through options
to apply, like --exclude and --directory. Add
--include to this list.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
apply: free unused fragments for submodule patch

We simply discarded the fragments that we are not going to use upon seeing
a patch to update the submodule commit bound at path that we have not
checked out.

Free these fragments, not to leak them.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
var doc: default editor and pager are configurable at build time

Some distributors customize the fallback pager and editor used by git
commands when the user has not indicated a preference via the
core.editor/core.pager configuration or GIT_EDITOR, GIT_PAGER, VISUAL,
EDITOR, and PAGER environment variables, and git's build system
provides DEFAULT_PAGER and DEFAULT_EDITOR makefile settings to help
them with that (see v1.6.6-rc0~24, 2009-11-20).

Unfortunately those compile-time settings do not affect the
documentation, so the uninitiated user who tries to understand git by
reading the git-var(1) manpage can easily be confused when git falls
back to 'nano' and 'more' instead of 'vi' and 'less'.  Even if the
distributor patches the distributed docs to reflect the new default,
the user may read the official documentation from the git-htmldocs
repository online and be confused in the same way.

Add a few words stating that the defaults are customizable at
compile time to make the behavior crystal clear.

Reported-by: Rodrigo Silva (MestreLion) <linux@rodrigosilva.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
push: error out when the "upstream" semantics does not make sense

The user can say "git push" without specifying any refspec.  When using
the "upstream" semantics via the push.default configuration, the user
wants to update the "upstream" branch of the current branch, which is the
branch at a remote repository the current branch is set to integrate with,
with this command.

However, there are cases that such a "git push" that uses the "upstream"
semantics does not make sense:

 - The current branch does not have branch.$name.remote configured.  By
   definition, "git push" that does not name where to push to will not
   know where to push to.  The user may explicitly say "git push $there",
   but again, by definition, no branch at repository $there is set to
   integrate with the current branch in this case and we wouldn't know
   which remote branch to update.

 - The current branch does have branch.$name.remote configured, but it
   does not specify branch.$name.merge that names what branch at the
   remote this branch integrates with. "git push" knows where to push in
   this case (or the user may explicitly say "git push $remote" to tell us
   where to push), but we do not know which remote branch to update.

 - The current branch does have its remote and upstream branch configured,
   but the user said "git push $there", where $there is not the remote
   named by "branch.$name.remote".  By definition, no branch at repository
   $there is set to integrate with the current branch in this case, and
   this push is not meant to update any branch at the remote repository
   $there.

The first two cases were already checked correctly, but the third case was
not checked and we ended up updating the branch named branch.$name.merge
at repository $there, which was totally bogus.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
compat/mingw.[ch]: Change return type of exec functions to int

The POSIX standard specifies a return type of int for all six exec
functions. In addition, all exec functions return -1 on error, and
simply do not return on success. However, the current emulation of
the exec functions on mingw are declared with a void return type.

This would cause a problem should any code attempt to call the
exec function in a non-void context. In particular, if an exec
function were used in a conditional it would fail to compile.

In order to improve the fidelity of the emulation, we change the
return type of the mingw_execv[p] functions to int and return -1
on error.

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
run-command: treat inaccessible directories as ENOENT

When execvp reports EACCES, it can be one of two things:

  1. We found a file to execute, but did not have
     permissions to do so.

  2. We did not have permissions to look in some directory
     in the $PATH.

In the former case, we want to consider this a
permissions problem and report it to the user as such (since
getting this for something like "git foo" is likely a
configuration error).

In the latter case, there is a good chance that the
inaccessible directory does not contain anything of
interest. Reporting "permission denied" is confusing to the
user (and prevents our usual "did you mean...?" lookup). It
also prevents git from trying alias lookup, since we do so
only when an external command does not exist (not when it
exists but has an error).

This patch detects EACCES from execvp, checks whether we are
in case (2), and if so converts errno to ENOENT. This
behavior matches that of "bash" (but not of simpler shells
that use execvp more directly, like "dash").

Test stolen from Junio.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Avoid bug in Solaris xpg4/sed as used in submodule

The sed provided by Solaris in /usr/xpg4/bin has a bug whereby an
unanchored regex using * for zero or more repetitions sees two
separate matches fed to the substitution engine in some cases.

This is evidenced by:

$ for sed in /usr/xpg4/bin/sed /usr/bin/sed /opt/csw/gnu/sed; do \
echo 'ab' | $sed -e 's|[a]*|X|g'; \
done
XXbX
XbX
XbX

This bug was triggered during a git submodule clone operation as
exercised in the setup stage of t5526-fetch-submodules when using the
default SANE_TOOL_PATH for Solaris.  It led to paths such as
..../.. being used in the submodule .git gitdir reference.

Using the expression 's|\([^/]*\(/*\)\)|..\2|g' provides the desired
result with all three three tested sed implementations but is harder
to read.  As we do not need to handle fully qualified paths though,
the expression could actually be [^/]+ which isn't properly handled
either.  Instead, use [^/][^/]*, as suggested by Andreas Schwab, which
works on all three tested sed implementations.

The new expression is semantically different than the original one.
It will not place a leading '..' on a fully qualified path as the
original expression did.  All of the paths being passed through this
regex are relative and did not rely on this behaviour so it's a safe
change.

Signed-off-by: Ben Walton <bwalton@artsci.utoronto.ca>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
git-p4: move to toplevel

Move git-p4 out of contrib/fast-import into the main code base,
aside other foreign SCM tools.

Signed-off-by: Pete Wyckoff <pw@padd.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>