( )⚙ D9268 chg: close file descriptors when starting the daemon

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Differential D9268

chg: close file descriptors when starting the daemon
ClosedPublic

Authored by Mathiasdm on Nov 2 2020, 8:20 AM.

Details

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Group Reviewers
hg-reviewers
Commits
rHG8711dc13474c: chg: close file descriptors when starting the daemon
Summary

It's good practice to close file descriptors when forking to start a daemon.
This did not appear to happen yet, which results in flock hanging
in one location in our system (because the chg daemon keeps
the locked file open).

Diff Detail

Repository
rHG Mercurial
Lint
Automatic diff as part of commit; lint not applicable.
Unit
Automatic diff as part of commit; unit tests not applicable.

Event Timeline

Mathiasdm created this revision.Nov 2 2020, 8:20 AM
Mathias De Mare <mathias.de_mare@nokia.com> added a commit: rHG8711dc13474c: chg: close file descriptors when starting the daemon.Nov 2 2020, 3:34 PM
This revision was not accepted when it landed; it landed in state Needs Review.
Closed by commit rHG8711dc13474c: chg: close file descriptors when starting the daemon (authored by Mathias De Mare <mathias.de_mare@nokia.com>). · Explain Why
This revision was automatically updated to reflect the committed changes.

Revision Contents
Changeset List

PathPackages
Mcontrib/chg/chg.c (26 lines)

Diff 23404

contrib/chg/chg.c

/* /*
* A fast client for Mercurial command server * A fast client for Mercurial command server
* *
* Copyright (c) 2011 Yuya Nishihara <yuya@tcha.org> * Copyright (c) 2011 Yuya Nishihara <yuya@tcha.org>
* *
* This software may be used and distributed according to the terms of the * This software may be used and distributed according to the terms of the
* GNU General Public License version 2 or any later version. * GNU General Public License version 2 or any later version.
*/ */
#include <assert.h> #include <assert.h>
#include <dirent.h>
#include <errno.h> #include <errno.h>
#include <fcntl.h> #include <fcntl.h>
#include <signal.h> #include <signal.h>
#include <stdio.h> #include <stdio.h>
#include <stdlib.h> #include <stdlib.h>
#include <string.h> #include <string.h>
#include <sys/file.h> #include <sys/file.h>
#include <sys/stat.h> #include <sys/stat.h>
if (putenv("CHG_CLEAR_LC_CTYPE=") != 0) if (putenv("CHG_CLEAR_LC_CTYPE=") != 0)
abortmsgerrno("failed to putenv CHG_CLEAR_LC_CTYPE"); abortmsgerrno("failed to putenv CHG_CLEAR_LC_CTYPE");
} else { } else {
if (setenv("CHGORIG_LC_CTYPE", lc_ctype_env, 1) != 0) { if (setenv("CHGORIG_LC_CTYPE", lc_ctype_env, 1) != 0) {
abortmsgerrno("failed to setenv CHGORIG_LC_CTYPE"); abortmsgerrno("failed to setenv CHGORIG_LC_CTYPE");
} }
} }
/* close any open files to avoid hanging locks */
DIR *dp = opendir("/proc/self/fd");
if (dp != NULL) {
debugmsg("closing files based on /proc contents");
struct dirent *de;
while ((de = readdir(dp))) {
char *end;
long fd_value = strtol(de->d_name, &end, 10);
if (end == de->d_name) {
/* unable to convert to int (. or ..) */
continue;
}
if (errno == ERANGE) {
debugmsg("tried to parse %s, but range error occurred", de->d_name);
continue;
}
if (fd_value > STDERR_FILENO) {
int res = close(fd_value);
if (res) {
debugmsg("tried to close fd %ld: %d (errno: %d)", fd_value, res, errno);
}
}
}
}
if (putenv("CHGINTERNALMARK=") != 0) if (putenv("CHGINTERNALMARK=") != 0)
abortmsgerrno("failed to putenv"); abortmsgerrno("failed to putenv");
if (execvp(hgcmd, (char **)argv) < 0) if (execvp(hgcmd, (char **)argv) < 0)
abortmsgerrno("failed to exec cmdserver"); abortmsgerrno("failed to exec cmdserver");
free(argv); free(argv);
} }
/* Retry until we can connect to the server. Give up after some time. */ /* Retry until we can connect to the server. Give up after some time. */