delta/git.git/pager.c, branch nd/unify-ref-parse

Merge branch 'je/pager-do-not-recurse'

2014-06-06T18:17:00+00:00

We used to unconditionally disable the pager in the pager process
we spawn to feed out output, but that prevented people who want to
run "less" within "less" from doing so.

* je/pager-do-not-recurse:
  pager: do allow spawning pager recursively

pager: remove 'S' from $LESS by default

2014-05-07T20:41:04+00:00

By default, Git used to set $LESS to -FRSX if $LESS was not set by
the user. The FRX flags actually make sense for Git (F and X because
sometimes the output Git pipes to less is short, and R because Git
pipes colored output). The S flag (chop long lines), on the other
hand, is not related to Git and is a matter of user preference. Git
should not decide for the user to change LESS's default.

More specifically, the S flag harms users who review untrusted code
within a pager, since a patch looking like:

    -old code;
    +new good code; [... lots of tabs ...] malicious code;

would appear identical to:

    -old code;
    +new good code;

Users who prefer the old behavior can still set the $LESS environment
variable to -FRSX explicitly, or set core.pager to 'less -S'.

The documentation in config.txt is made a bit longer to keep both an
example setting the 'S' flag (needed to recover the old behavior)
and an example showing how to unset a flag set by Git.

Signed-off-by: Matthieu Moy 
Signed-off-by: Junio C Hamano

pager: do allow spawning pager recursively

2014-04-28T23:03:22+00:00

This reverts commit 88e8f908f2b0c56f9ccf8134d8ff9f689af9cc84, which
tried to allow

    GIT_PAGER="git -p column --mode='dense color'" git -p branch

and still wanted to avoid "git -p column" to invoke itself.  However,
this falls into "don't do that -p then" category.

In particular, inside "git log", with results going through less, a
potentially interesting commit may be found and from there inside
"less", the user may want to execute "git show ".  Before
the commit being reverted, this used to show the patch in less but
it no longer does.

Signed-off-by: Jörn Engel 
Reviewed-by: Jeff King 
Reviewed-by: Matthieu Moy 
Acked-by: Duy Nguyen 
Signed-off-by: Junio C Hamano

Merge branch 'jn/pager-lv-default-env'

2014-01-13T19:33:35+00:00

Just like we give a reasonable default for "less" via the LESS
environment variable, specify a reasonable default for "lv" via the
"LV" environment variable when spawning the pager.

* jn/pager-lv-default-env:
  pager: set LV=-c alongside LESS=FRSX

pager: set LV=-c alongside LESS=FRSX

2014-01-07T17:23:41+00:00

On systems with lv configured as the preferred pager (i.e.,
DEFAULT_PAGER=lv at build time, or PAGER=lv exported in the
environment) git commands that use color show control codes instead of
color in the pager:

	$ git diff
	^[[1mdiff --git a/.mailfilter b/.mailfilter^[[m
	^[[1mindex aa4f0b2..17e113e 100644^[[m
	^[[1m--- a/.mailfilter^[[m
	^[[1m+++ b/.mailfilter^[[m
	^[[36m@@ -1,11 +1,58 @@^[[m

"less" avoids this problem because git uses the LESS environment
variable to pass the -R option ('output ANSI color escapes in raw
form') by default.  Use the LV environment variable to pass 'lv' the
-c option ('allow ANSI escape sequences for text decoration / color')
to fix it for lv, too.

Noticed when the default value for color.ui flipped to 'auto' in
v1.8.4-rc0~36^2~1 (2013-06-10).

Reported-by: Olaf Meeuwissen 
Signed-off-by: Jonathan Nieder 
Signed-off-by: Junio C Hamano

replace {pre,suf}fixcmp() with {starts,ends}_with()

2013-12-05T22:13:21+00:00

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 
Signed-off-by: Junio C Hamano

pager: turn on "cat" optimization for DEFAULT_PAGER

2013-09-03T17:36:12+00:00

If the user specifies a pager of "cat" (or the empty
string), whether it is in the environment or from config, we
automagically optimize it out to mean "no pager" and avoid
forking at all. We treat an empty pager variable similary.

However, we did not apply this optimization when
DEFAULT_PAGER was set to "cat" (or the empty string). There
is no reason to treat DEFAULT_PAGER any differently. The
optimization should not be user-visible (unless the user has
a bizarre "cat" in their PATH). And even if it is, we are
better off behaving consistently between the compile-time
default and the environment and config settings.

The stray "else" we are removing from this code was
introduced by 402461a (pager: do not fork a pager if PAGER
is set to empty., 2006-04-16). At that time, the line
directly above used:

   if (!pager)
	   pager = "less";

as a fallback, meaning that it could not possibly trigger
the optimization. Later, a3d023d (Provide a build time
default-pager setting, 2009-10-30) turned that constant into
a build-time setting which could be anything, but didn't
loosen the "else" to let DEFAULT_PAGER use the optimization.

Noticed-by: Dale R. Worley 
Suggested-by: Matthieu Moy 
Signed-off-by: Jeff King 
Signed-off-by: Junio C Hamano

Move setup_diff_pager to libgit.a

2012-10-29T07:08:30+00:00

This is used by diff-no-index.c, part of libgit.a while it stays in
builtin/diff.c. Move it to diff.c so that we won't get undefined
reference if a program that uses libgit.a happens to pull it in.

While at it, move check_pager from git.c to pager.c. It makes more
sense there and pager.c is also part of libgit.a

Signed-off-by: Nguyễn Thái Ngọc Duy 
Signed-off-by: Jeff King

pager: drop "wait for output to run less" hack

2012-06-05T16:38:00+00:00

Commit 35ce862 (pager: Work around window resizing bug in
'less', 2007-01-24) causes git's pager sub-process to wait
to receive input after forking but before exec-ing the
pager. To handle this, run-command had to grow a "pre-exec
callback" feature. Unfortunately, this feature does not work
at all on Windows (where we do not fork), and interacts
poorly with run-command's parent notification system. Its
use should be discouraged.

The bug in less was fixed in version 406, which was released
in June 2007. It is probably safe at this point to remove
our workaround. That lets us rip out the preexec_cb feature
entirely.

Signed-off-by: Jeff King 
Signed-off-by: Junio C Hamano

Stop starting pager recursively

2012-04-27T16:26:38+00:00

git-column can be used as a pager for other git commands, something
like this:

    GIT_PAGER="git -p column --mode='dense color'" git -p branch

The problem with this is that "git -p column" also has $GIT_PAGER set so
the pager runs itself again as another pager. The end result is an
infinite loop of forking. Other git commands have the same problem if
being abused this way.

Check if $GIT_PAGER is already set and stop launching another pager.

Signed-off-by: Nguyễn Thái Ngọc Duy 
Signed-off-by: Junio C Hamano