apply.c:update_pre_post_images(): the preimage can be truncated

5166714 (apply: Allow blank context lines to match beyond EOF,
2010-03-06) and then later 0c3ef98 (apply: Allow blank *trailing*
context lines to match beyond EOF, 2010-04-08) taught "git apply"
to trim new blank lines at the end in the patch text when matching
the contents being patched and the preimage recorded in the patch,
under --whitespace=fix mode.

When a preimage is modified to match the current contents in
preparation for such a "fixed" patch application, the context lines
in the postimage must be updated to match (otherwise, it would
reintroduce whitespace breakages), and update_pre_post_images()
function is responsible for doing this.  However, this function was
not updated to take into account a case where the removal of
trailing blank lines reduces the number of lines in the preimage,
and triggered an assertion error.

The logic to fix the postimage by copying the corrected context
lines from the preimage was not prepared to handle this case,
either, but it was protected by the assert() and only got exposed
when the assertion is corrected.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
config, gitignore: failure to access with ENOTDIR is ok

The access_or_warn() function is used to check for optional
configuration files like .gitconfig and .gitignore and warn when they
are not accessible due to a configuration issue (e.g., bad
permissions).  It is not supposed to complain when a file is simply
missing.

Noticed on a system where ~/.config/git was a file --- when the new
XDG_CONFIG_HOME support looks for ~/.config/git/config it should
ignore ~/.config/git instead of printing irritating warnings:

 $ git status -s
 warning: unable to access '/home/jrn/.config/git/config': Not a directory
 warning: unable to access '/home/jrn/.config/git/config': Not a directory
 warning: unable to access '/home/jrn/.config/git/config': Not a directory
 warning: unable to access '/home/jrn/.config/git/config': Not a directory

Compare v1.7.12.1~2^2 (attr:failure to open a .gitattributes file
is OK with ENOTDIR, 2012-09-13).

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
config: treat user and xdg config permission problems as errors

Git reads multiple configuration files: settings come first from the
system config file (typically /etc/gitconfig), then the xdg config
file (typically ~/.config/git/config), then the user's dotfile
(~/.gitconfig), then the repository configuration (.git/config).

Git has always used access(2) to decide whether to use each file; as
an unfortunate side effect, that means that if one of these files is
unreadable (e.g., EPERM or EIO), git skips it.  So if I use
~/.gitconfig to override some settings but make a mistake and give it
the wrong permissions then I am subject to the settings the sysadmin
chose for /etc/gitconfig.

Better to error out and ask the user to correct the problem.

This only affects the user and xdg config files, since the user
presumably has enough access to fix their permissions.  If the system
config file is unreadable, the best we can do is to warn about it so
the user knows to notify someone and get on with work in the meantime.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
doc: advertise GIT_CONFIG_NOSYSTEM

On a multiuser system where mortals do not have write access to /etc,
the GIT_CONFIG_NOSYSTEM variable is the best tool we have to keep
getting work done when a syntax error or other problem renders
/etc/gitconfig buggy, until the sysadmin sorts the problem out.

Noticed while experimenting with teaching git to error out when
/etc/gitconfig is unreadable.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
config: exit on error accessing any config file

There is convenience in warning and moving on when somebody has a
bogus permissions on /etc/gitconfig and cannot do anything about it.
But the cost in predictability and security is too high --- when
unreadable config files are skipped, it means an I/O error or
permissions problem causes important configuration to be bypassed.

For example, servers may depend on /etc/gitconfig to enforce security
policy (setting transfer.fsckObjects or receive.deny*).  Best to
always error out when encountering trouble accessing a config file.

This may add inconvenience in some cases:

  1. You are inspecting somebody else's repo, and you do not have
     access to their .git/config file.  Git typically dies in this
     case already since we cannot read core.repositoryFormatVersion,
     so the change should not be too noticeable.

  2. You have used "sudo -u" or a similar tool to switch uid, and your
     environment still points Git at your original user's global
     config, which is not readable.  In this case people really would
     be inconvenienced (they would rather see the harmless warning and
     continue the operation) but they can work around it by setting
     HOME appropriately after switching uids.

  3. You do not have access to /etc/gitconfig due to a broken setup.
     In this case, erroring out is a good way to put pressure on the
     sysadmin to fix the setup.  While they wait for a reply, users
     can set GIT_CONFIG_NOSYSTEM to true to keep Git working without
     complaint.

After this patch, errors accessing the repository-local and systemwide
config files and files requested in include directives cause Git to
exit, just like errors accessing ~/.gitconfig.

Explained-by: Jeff King <peff@peff.net>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
completion: add new __gitcompadd helper

The idea is to never touch the COMPREPLY variable directly.

This allows other completion systems override __gitcompadd, and do
something different instead.

Also, this allows the simplifcation of the completino tests (separate
patch).

There should be no functional changes.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
tests: use __gitcompadd to simplify completion tests

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
completion: add new zsh completion

It seems there's always issues with zsh's bash completion emulation.
I've tried to fix as many as I could and most of the fixes are already
in the latest version of zsh, but still, there are issues.

There is no point in going through all that pain; the emulation is easy
to achieve, and this patch works better than zsh's emulation.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
git-cvsimport: allow author-specific timezones

CVS patchsets are imported with timestamps having an offset of +0000
(UTC).  The cvs-authors file is already used to translate the CVS
username to full name and email in the corresponding commit.  Extend
this file to support an optional timezone for calculating a user-
specific timestamp offset.

Signed-off-by: Chris Rorvick <chris@rorvick.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
exclude: stricten a length check in EXC_FLAG_ENDSWITH case

This block of code deals with the "basename" part only, which has the
length of "pathlen - (basename - pathname)". Stricten the length check
and remove "pathname" from the main expression to avoid confusion.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
exclude: split basename matching code into a separate function

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
exclude: fix a bug in prefix compare optimization

When "namelen" becomes zero at this stage, we have matched the fixed
part, but whether it actually matches the pattern still depends on the
pattern in "exclude". As demonstrated in t3001, path "three/a.3"
exists and it matches the "three/a.3" part in pattern "three/a.3[abc]",
but that does not mean a true match.

Don't be too optimistic and let fnmatch() do the job.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
exclude: split pathname matching code into a separate function

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
gitignore: make pattern parsing code a separate function

This function can later be reused by attr.c. Also turn to_exclude
field into a flag.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
attr: more matching optimizations from .gitignore

.gitattributes and .gitignore share the same pattern syntax but has
separate matching implementation. Over the years, ignore's
implementation accumulates more optimizations while attr's stays the
same.

This patch reuses the core matching functions that are also used by
excluded_from_list. excluded_from_list and path_matches can't be
merged due to differences in exclude and attr, for example:

* "!pattern" syntax is forbidden in .gitattributes.  As an attribute
  can be unset (i.e. set to a special value "false") or made back to
  unspecified (i.e. not even set to "false"), "!pattern attr" is unclear
  which one it means.

* we support attaching attributes to directories, but git-core
  internally does not currently make use of attributes on
  directories.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
ctype: make sane_ctype[] const array

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
ctype: support iscntrl, ispunct, isxdigit and isprint

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Import wildmatch from rsync

These files are from rsync.git commit
f92f5b166e3019db42bc7fe1aa2f1a9178cd215d, which was the last commit
before rsync turned GPL-3. All files are imported as-is and
no-op. Adaptation is done in a separate patch.

rsync.git           ->  git.git
lib/wildmatch.[ch]      wildmatch.[ch]
wildtest.txt            t/t3070/wildtest.txt

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
wildmatch: remove unnecessary functions

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
wildmatch: follow Git's coding convention

wildmatch's coding style is pretty close to Git's except the use of 4
space indentation instead of 8. This patch should produce empty diff
with "git diff -b"

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>