mirror of
https://github.com/git/git.git
synced 2024-11-25 19:04:18 +08:00
61b80509e3
If you do this (and you are not an Emacs user who uses PAGER=cat
in your *shell* buffer):
$ git init
Initialized empty Git repository in .git/
$ echo hello world >foo
$ H=$(git hash-object -w foo)
$ git tag -a foo-tag -m "Tags $H" $H
$ echo $H
3b18e512db
$ rm -f .git/objects/3b/18e5*
$ git show foo-tag
tag foo-tag
Tagger: Junio C Hamano <gitster@pobox.com>
Date: Sat Feb 16 10:43:23 2008 -0800
Tags 3b18e512db
you do not get any indication of error. If you are careful, you
would notice that no contents from the tagged object is
displayed, but that is about it. If you run the "show" command
without pager, however, you will see the error:
$ git --no-pager show foo-tag
tag foo-tag
Tagger: Junio C Hamano <gitster@pobox.com>
Date: Sat Feb 16 10:43:23 2008 -0800
Tags 3b18e512db
error: Could not read object 3b18e512db
Because we spawn the pager as the foreground process and feed
its input via pipe from the real command, we cannot affect the
exit status the shell sees from git command when the pager is in
use (I think there is not much gain we can have by working it
around, though). But at least it may make sense to show the
error message to the user sitting in front of the pager.
[jc: Edgar Toernig suggested a much nicer implementation than
what I originally posted, which I took.]
Signed-off-by: Junio C Hamano <gitster@pobox.com>
87 lines
1.4 KiB
C
87 lines
1.4 KiB
C
#include "cache.h"
|
|
|
|
/*
|
|
* This is split up from the rest of git so that we might do
|
|
* something different on Windows, for example.
|
|
*/
|
|
|
|
static int spawned_pager;
|
|
|
|
static void run_pager(const char *pager)
|
|
{
|
|
/*
|
|
* Work around bug in "less" by not starting it until we
|
|
* have real input
|
|
*/
|
|
fd_set in;
|
|
|
|
FD_ZERO(&in);
|
|
FD_SET(0, &in);
|
|
select(1, &in, NULL, &in, NULL);
|
|
|
|
execlp(pager, pager, NULL);
|
|
execl("/bin/sh", "sh", "-c", pager, NULL);
|
|
}
|
|
|
|
void setup_pager(void)
|
|
{
|
|
pid_t pid;
|
|
int fd[2];
|
|
const char *pager = getenv("GIT_PAGER");
|
|
|
|
if (!isatty(1))
|
|
return;
|
|
if (!pager) {
|
|
if (!pager_program)
|
|
git_config(git_default_config);
|
|
pager = pager_program;
|
|
}
|
|
if (!pager)
|
|
pager = getenv("PAGER");
|
|
if (!pager)
|
|
pager = "less";
|
|
else if (!*pager || !strcmp(pager, "cat"))
|
|
return;
|
|
|
|
spawned_pager = 1; /* means we are emitting to terminal */
|
|
|
|
if (pipe(fd) < 0)
|
|
return;
|
|
pid = fork();
|
|
if (pid < 0) {
|
|
close(fd[0]);
|
|
close(fd[1]);
|
|
return;
|
|
}
|
|
|
|
/* return in the child */
|
|
if (!pid) {
|
|
dup2(fd[1], 1);
|
|
dup2(fd[1], 2);
|
|
close(fd[0]);
|
|
close(fd[1]);
|
|
return;
|
|
}
|
|
|
|
/* The original process turns into the PAGER */
|
|
dup2(fd[0], 0);
|
|
close(fd[0]);
|
|
close(fd[1]);
|
|
|
|
setenv("LESS", "FRSX", 0);
|
|
run_pager(pager);
|
|
die("unable to execute pager '%s'", pager);
|
|
exit(255);
|
|
}
|
|
|
|
int pager_in_use(void)
|
|
{
|
|
const char *env;
|
|
|
|
if (spawned_pager)
|
|
return 1;
|
|
|
|
env = getenv("GIT_PAGER_IN_USE");
|
|
return env ? git_config_bool("GIT_PAGER_IN_USE", env) : 0;
|
|
}
|