Commit Graph

29 Commits

Author SHA1 Message Date
Ævar Arnfjörð Bjarmason
c7c4bdeccf run-command API: remove "env" member, always use "env_array"
Remove the "env" member from "struct child_process" in favor of always
using the "env_array". As with the preceding removal of "argv" in
favor of "args" this gets rid of current and future oddities around
memory management at the API boundary (see the amended API docs).

For some of the conversions we can replace patterns like:

    child.env = env->v;

With:

    strvec_pushv(&child.env_array, env->v);

But for others we need to guard the strvec_pushv() with a NULL check,
since we're not passing in the "v" member of a "struct strvec",
e.g. in the case of tmp_objdir_env()'s return value.

Ideally we'd rename the "env_array" member to simply "env" as a
follow-up, since it and "args" are now inconsistent in not having an
"_array" suffix, and seemingly without any good reason, unless we look
at the history of how they came to be.

But as we've currently got 122 in-tree hits for a "git grep env_array"
let's leave that for now (and possibly forever). Doing that rename
would be too disruptive.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-11-25 22:15:08 -08:00
Ævar Arnfjörð Bjarmason
2b7098936c run-command API users: use strvec_pushl(), not argv construction
Change a pattern of hardcoding an "argv" array size, populating it and
assigning to the "argv" member of "struct child_process" to instead
use "strvec_pushl()" to add data to the "args" member.

This implements the same behavior as before in fewer lines of code,
and moves us further towards being able to remove the "argv" member in
a subsequent commit.

Since we've entirely removed the "argv" variable(s) we can be sure
that no potential logic errors of the type discussed in a preceding
commit are being introduced here, i.e. ones where the local "argv" was
being modified after the assignment to "struct child_process"'s
"argv".

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-11-25 22:15:07 -08:00
Junio C Hamano
4150a1677b Merge branch 'jc/save-restore-terminal-revert'
Regression fix for 2.34

* jc/save-restore-terminal-revert:
  Revert "editor: save and reset terminal after calling EDITOR"
2021-11-22 18:40:11 -08:00
Junio C Hamano
e3f7e01b50 Revert "editor: save and reset terminal after calling EDITOR"
This reverts commit 3d411afabc,
blindly opening /dev/tty and calling tcsetattr() seems to be causing
problems.

cf. https://bugs.eclipse.org/bugs/show_bug.cgi?id=577358
cf. https://lore.kernel.org/git/04ab7301-ea34-476c-eae4-4044fef74b91@gmail.com/

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-11-22 15:04:20 -08:00
Junio C Hamano
853ec9aa9b Merge branch 'cm/save-restore-terminal'
An editor session launched during a Git operation (e.g. during 'git
commit') can leave the terminal in a funny state.  The code path
has updated to save the terminal state before, and restore it
after, it spawns an editor.

* cm/save-restore-terminal:
  editor: save and reset terminal after calling EDITOR
  terminal: teach git how to save/restore its terminal settings
2021-10-18 15:47:57 -07:00
Carlo Marcelo Arenas Belón
3d411afabc editor: save and reset terminal after calling EDITOR
When EDITOR is invoked to modify a commit message, it will likely
change the terminal settings, and if it misbehaves will leave the
terminal output damaged as shown in a recent report from Windows
Terminal[1]

Instead use the functions provided by compat/terminal to save the
settings and recover safely.

[1] https://github.com/microsoft/terminal/issues/9359

Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-06 08:53:03 -07:00
Ben Boeckel
ed9bff0817 advice: remove read uses of most global advice_ variables
In c4a09cc9cc (Merge branch 'hw/advise-ng', 2020-03-25), a new API for
accessing advice variables was introduced and deprecated `advice_config`
in favor of a new array, `advice_setting`.

This patch ports all but two uses which read the status of the global
`advice_` variables over to the new `advice_enabled` API. We'll deal
with advice_add_embedded_repo and advice_graft_file_deprecated
separately.

Signed-off-by: Ben Boeckel <mathstuf@gmail.com>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-08-25 12:07:52 -07:00
Jeff King
f1de981e8b config: fix leaks from git_config_get_string_const()
There are two functions to get a single config string:

  - git_config_get_string()

  - git_config_get_string_const()

One might naively think that the first one allocates a new string and
the second one just points us to the internal configset storage. But
in fact they both allocate a new copy; the second one exists only to
avoid having to cast when using it with a const global which we never
intend to free.

The documentation for the function explains that clearly, but it seems
I'm not alone in being surprised by this. Of 17 calls to the function,
13 of them leak the resulting value.

We could obviously fix these by adding the appropriate free(). But it
would be simpler still if we actually had a non-allocating way to get
the string. There's git_config_get_value() but that doesn't quite do
what we want. If the config key is present but is a boolean with no
value (e.g., "[foo]bar" in the file), then we'll get NULL (whereas the
string versions will print an error and die).

So let's introduce a new variant, git_config_get_string_tmp(), that
behaves as these callers expect. We need a new name because we have new
semantics but the same function signature (so even if we converted the
four remaining callers, topics in flight might be surprised). The "tmp"
is because this value should only be held onto for a short time. In
practice it's rare for us to clear and refresh the configset,
invalidating the pointer, but hopefully the "tmp" makes callers think
about the lifetime. In each of the converted cases here the value only
needs to last within the local function or its immediate caller.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-14 10:52:04 -07:00
Alexandr Miloslavskiy
3d7747e318 real_path: remove unsafe API
Returning a shared buffer invites very subtle bugs due to reentrancy or
multi-threading, as demonstrated by the previous patch.

There was an unfinished effort to abolish this [1].

Let's finally rid of `real_path()`, using `strbuf_realpath()` instead.

This patch uses a local `strbuf` for most places where `real_path()` was
previously called.

However, two places return the value of `real_path()` to the caller. For
them, a `static` local `strbuf` was added, effectively pushing the
problem one level higher:
    read_gitfile_gently()
    get_superproject_working_tree()

[1] https://lore.kernel.org/git/1480964316-99305-1-git-send-email-bmwill@google.com/

Signed-off-by: Alexandr Miloslavskiy <alexandr.miloslavskiy@syntevo.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-03-10 11:41:40 -07:00
SZEDER Gábor
cd1096b282 pager: add a helper function to clear the last line in the terminal
There are a couple of places where we want to clear the last line on
the terminal, e.g. when a progress bar line is overwritten by a
shorter line, then the end of that progress line would remain visible,
unless we cover it up.

In 'progress.c' we did this by always appending a fixed number of
space characters to the next line (even if it was not shorter than the
previous), but as it turned out that fixed number was not quite large
enough, see the fix in 9f1fd84e15 (progress: clear previous progress
update dynamically, 2019-04-12).  From then on we've been keeping
track of the length of the last displayed progress line and appending
the appropriate number of space characters to the next line, if
necessary, but, alas, this approach turned out to be error prone, see
the fix in 1aed1a5f25 (progress: avoid empty line when breaking the
progress line, 2019-05-19).  The next patch in this series is about to
fix a case where we don't clear the last line, and on occasion do end
up with such garbage at the end of the line.  It would be great if we
could do that without the need to deal with that without meticulously
computing the necessary number of space characters.

So add a helper function to clear the last line on the terminal using
an ANSI escape sequence, which has the advantage to clear the whole
line no matter how wide it is, even after the terminal width changed.
Such an escape sequence is not available on dumb terminals, though, so
in that case fall back to simply print a whole terminal width (as
reported by term_columns()) worth of space characters.

In 'editor.c' launch_specified_editor() already used this ANSI escape
sequence, so replace it with a call to this function.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-06-24 13:38:46 -07:00
Jeff Hostetler
eee73d1dce trace2:data: add editor/pager child classification
Add trace2 process classification for editor and pager
child processes.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-02-22 15:27:59 -08:00
Alban Gruin
2aed01811d editor: add a function to launch the sequence editor
As part of the rewrite of interactive rebase, the sequencer will need to
open the sequence editor to allow the user to edit the todo list.
Instead of duplicating the existing launch_editor() function, this
refactors it to a new function, launch_specified_editor(), which takes
the editor as a parameter, in addition to the path, the buffer and the
environment variables.  launch_sequence_editor() is then added to launch
the sequence editor.

Signed-off-by: Alban Gruin <alban.gruin@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-10 11:56:22 -07:00
Lars Schneider
abfb04d0c7 launch_editor(): indicate that Git waits for user input
When a graphical GIT_EDITOR is spawned by a Git command that opens
and waits for user input (e.g. "git rebase -i"), then the editor window
might be obscured by other windows. The user might be left staring at
the original Git terminal window without even realizing that s/he needs
to interact with another window before Git can proceed. To this user Git
appears hanging.

Print a message that Git is waiting for editor input in the original
terminal and get rid of it when the editor returns, if the terminal
supports erasing the last line.  Also, make sure that our message is
terminated with a whitespace so that any message the editor may show
upon starting up will be kept separate from our message.

Power users might not want to see this message or their editor might
already print such a message (e.g. emacsclient). Allow these users to
suppress the message by disabling the "advice.waitingForEditor" config.

The standard advise() function is not used here as it would always add
a newline which would make deleting the message harder.

Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Lars Schneider <larsxschneider@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-12-07 10:10:19 -08:00
Lars Schneider
a64f213d3f refactor "dumb" terminal determination
Move the code to detect "dumb" terminals into a single location. This
avoids duplicating the terminal detection code yet again in a subsequent
commit.

Signed-off-by: Lars Schneider <larsxschneider@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-12-04 09:38:30 -08:00
Nguyễn Thái Ngọc Duy
9f9a522c15 editor.c: use error_errno()
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-05-09 12:29:08 -07:00
René Scharfe
d318027932 run-command: introduce CHILD_PROCESS_INIT
Most struct child_process variables are cleared using memset first after
declaration.  Provide a macro, CHILD_PROCESS_INIT, that can be used to
initialize them statically instead.  That's shorter, doesn't require a
function call and is slightly more readable (especially given that we
already have STRBUF_INIT, ARGV_ARRAY_INIT etc.).

Helped-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-08-20 09:53:37 -07:00
Ramkumar Ramachandra
09c5ae5a50 editor: use canonicalized absolute path
By improving the relative_path() algorithm, e02ca72 (path.c:
refactor relative_path(), not only strip prefix, 2013-06-25)
uncovered a latent bug in Emacs.  While most editor applications
like cat and vim handle non-canonicalized relative paths fine, emacs
does not.  This is due to a long-standing bug in emacs, where it
refuses to resolve symlinks in the supplied path:

  #!/bin/sh
  cd /tmp
  mkdir z z/a z/b
  echo moodle >z/a/file
  ln -s z/b
  cd b
  emacs ../a/file # fail: attempts to open /tmp/a/file

Even if emacs were to be patched to fix this bug, it may be nicer to
help users running older versions.

Note that this can potentially regress for users of all editors,
when they ask "what file am I editing?" to the editor, as it is
likely to answer with an unsightly long full path.

Co-authored-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-07-29 12:15:27 -07:00
Jeff King
709ca730f8 run-command: encode signal death as a positive integer
When a sub-command dies due to a signal, we encode the
signal number into the numeric exit status as "signal -
128". This is easy to identify (versus a regular positive
error code), and when cast to an unsigned integer (e.g., by
feeding it to exit), matches what a POSIX shell would return
when reporting a signal death in $? or through its own exit
code.

So we have a negative value inside the code, but once it
passes across an exit() barrier, it looks positive (and any
code we receive from a sub-shell will have the positive
form). E.g., death by SIGPIPE (signal 13) will look like
-115 to us in inside git, but will end up as 141 when we
call exit() with it. And a program killed by SIGPIPE but run
via the shell will come to us with an exit code of 141.

Unfortunately, this means that when the "use_shell" option
is set, we need to be on the lookout for _both_ forms. We
might or might not have actually invoked the shell (because
we optimize out some useless shell calls). If we didn't invoke
the shell, we will will see the sub-process's signal death
directly, and run-command converts it into a negative value.
But if we did invoke the shell, we will see the shell's
128+signal exit status. To be thorough, we would need to
check both, or cast the value to an unsigned char (after
checking that it is not -1, which is a magic error value).

Fortunately, most callsites do not care at all whether the
exit was from a code or from a signal; they merely check for
a non-zero status, and sometimes propagate the error via
exit(). But for the callers that do care, we can make life
slightly easier by just using the consistent positive form.

This actually fixes two minor bugs:

  1. In launch_editor, we check whether the editor died from
     SIGINT or SIGQUIT. But we checked only the negative
     form, meaning that we would fail to notice a signal
     death exit code which was propagated through the shell.

  2. In handle_alias, we assume that a negative return value
     from run_command means that errno tells us something
     interesting (like a fork failure, or ENOENT).
     Otherwise, we simply propagate the exit code. Negative
     signal death codes confuse us, and we print a useless
     "unable to run alias 'foo': Success" message. By
     encoding signal deaths using the positive form, the
     existing code just propagates it as it would a normal
     non-zero exit code.

The downside is that callers of run_command can no longer
differentiate between a signal received directly by the
sub-process, and one propagated. However, no caller
currently cares, and since we already optimize out some
calls to the shell under the hood, that distinction is not
something that should be relied upon by callers.

Fix the same logic in t/test-terminal.perl for consistency [jc:
raised by Jonathan in the discussion].

Signed-off-by: Jeff King <peff@peff.net>
Acked-by: Johannes Sixt <j6t@kdbg.org>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-01-06 11:09:18 -08:00
Jeff King
1250857c6c launch_editor: propagate signals from editor to git
We block SIGINT and SIGQUIT while the editor runs so that
git is not killed accidentally by a stray "^C" meant for the
editor or its subprocesses. This works because most editors
ignore SIGINT.

However, some editor wrappers, like emacsclient, expect to
die due to ^C. We detect the signal death in the editor and
properly exit, but not before writing a useless error
message to stderr. Instead, let's notice when the editor was
killed by a terminal signal and just raise the signal on
ourselves.  This skips the message and looks to our parent
like we received SIGINT ourselves.

The end effect is that if the user's editor ignores SIGINT,
we will, too. And if it does not, then we will behave as if
we did not ignore it. That should make all users happy.

Note that in the off chance that another part of git has
ignored SIGINT while calling launch_editor, we will still
properly detect and propagate the failed return code from
the editor (i.e., the worst case is that we generate the
useless error, not fail to notice the editor's death).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-12-02 02:07:08 -08:00
Paul Fox
913ef36093 launch_editor: ignore terminal signals while editor has control
The user's editor likely catches SIGINT (ctrl-C).  but if
the user spawns a command from the editor and uses ctrl-C to
kill that command, the SIGINT will likely also kill git
itself (depending on the editor, this can leave the terminal
in an unusable state).

Let's ignore it while the editor is running, and do the same
for SIGQUIT, which many editors also ignore. This matches
the behavior if we were to use system(3) instead of
run-command.

Signed-off-by: Paul Fox <pgf@foxharp.boston.ma.us>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-12-02 02:06:04 -08:00
Jeff King
f42ca31d8d launch_editor: refactor to use start/finish_command
The launch_editor function uses the convenient run_command_*
interface. Let's use the more flexible start_command and
finish_command functions, which will let us manipulate the
parent state while we're waiting for the child to finish.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-12-02 02:05:41 -08:00
Jeff King
bac8037081 editor: use run_command's shell feature
Now that run_command implements the same code in a more
general form, we can make use of it.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-01-05 23:41:51 -08:00
Jonathan Nieder
8f4b576ad1 Provide a build time default-editor setting
Provide a DEFAULT_EDITOR knob to allow setting the fallback
editor to use instead of vi (when VISUAL, EDITOR, and GIT_EDITOR
are unset).  The value can be set at build time according to a
system’s policy.  For example, on Debian systems, the default
editor should be the 'editor' command.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Ben Walton <bwalton@artsci.utoronto.ca>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-11-13 12:20:54 -08:00
Jonathan Nieder
44fcb4977c Teach git var about GIT_EDITOR
Expose the command used by launch_editor() for scripts to use.
This should allow one to avoid searching for a proper editor
separately in each command.

git_editor(void) uses the logic to decide which editor to use
that used to live in launch_editor().  The function returns NULL
if there is no suitable editor; the caller is expected to issue
an error message when appropriate.

launch_editor() uses git_editor() and gives the error message the
same way as before when EDITOR is not set.

"git var GIT_EDITOR" gives the editor name, or an error message
when there is no appropriate one.

"git var -l" gives GIT_EDITOR=name only if there is an
appropriate editor.

Originally-submitted-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-11-13 12:17:00 -08:00
Jonathan Nieder
d33738d7d3 Do not use VISUAL editor on dumb terminals
Refuse to use $VISUAL and fall back to $EDITOR if TERM is unset
or set to "dumb".  Traditionally, VISUAL is set to a screen
editor and EDITOR to a line-based editor, which should be more
useful in that situation.

vim, for example, is happy to assume a terminal supports ANSI
sequences even if TERM is dumb (e.g., when running from a text
editor like Acme).  git already refuses to fall back to vi on a
dumb terminal if GIT_EDITOR, core.editor, VISUAL, and EDITOR are
unset, but without this patch, that check is suppressed by
VISUAL=vi.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-11-13 12:15:28 -08:00
Jonathan Nieder
eab58f1e8e Handle more shell metacharacters in editor names
Pass the editor name to the shell if it contains any susv3 shell
special character (globs, redirections, variable substitutions,
escapes, etc).  This way, the meaning of some characters will not
meaninglessly change when others are added, and git commands
implemented in C and in shell scripts will interpret editor names
in the same way.

This does not make the GIT_EDITOR setting any more expressive,
since one could always use single quotes to force the editor to
be passed to the shell.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-10-30 19:15:38 -07:00
Brandon Casey
f285a2d7ed Replace calls to strbuf_init(&foo, 0) with STRBUF_INIT initializer
Many call sites use strbuf_init(&foo, 0) to initialize local
strbuf variable "foo" which has not been accessed since its
declaration. These can be replaced with a static initialization
using the STRBUF_INIT macro which is just as readable, saves a
function call, and takes up fewer lines.

Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2008-10-12 12:36:19 -07:00
Stephan Beyer
7198203ae3 editor.c: Libify launch_editor()
This patch removes exit()/die() calls and builtin-specific messages
from launch_editor(), so that it can be used as a general libgit.a
function to launch an editor.

Signed-off-by: Stephan Beyer <s-beyer@gmx.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-07-25 17:09:38 -07:00
Stephan Beyer
d82f33e20d Move launch_editor() from builtin-tag.c to editor.c
launch_editor() is declared in strbuf.h but defined in builtin-tag.c.
This patch moves launch_editor() into a new source file editor.c,
but keeps the declaration in strbuf.h.

Signed-off-by: Stephan Beyer <s-beyer@gmx.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-07-25 17:08:34 -07:00