Files
deskflow/src/lib/arch/unix/ArchDaemonUnix.cpp
2025-08-11 17:14:45 +01:00

109 lines
2.5 KiB
C++

/*
* Deskflow -- mouse and keyboard sharing utility
* SPDX-FileCopyrightText: (C) 2025 Deskflow Developers
* SPDX-FileCopyrightText: (C) 2012 - 2016 Symless Ltd.
* SPDX-FileCopyrightText: (C) 2002 Chris Schoeneman
* SPDX-License-Identifier: GPL-2.0-only WITH LicenseRef-OpenSSL-Exception
*/
#include "arch/unix/ArchDaemonUnix.h"
#include "arch/ArchException.h"
#include "arch/unix/XArchUnix.h"
#include "base/Log.h"
#include <cstdlib>
#include <errno.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
//
// ArchDaemonUnix
//
#ifdef __APPLE__
// In Mac OS X, fork()'d child processes can't use most APIs (the frameworks
// that Deskflow uses in fact prevent it and make the process just up and die),
// so need to exec a copy of the program that doesn't fork so isn't limited.
int execSelfNonDaemonized()
{
extern char **NXArgv;
char **selfArgv = NXArgv;
setenv("_DESKFLOW_DAEMONIZED", "", 1);
execvp(selfArgv[0], selfArgv);
return 0;
}
bool alreadyDaemonized()
{
return std::getenv("_DESKFLOW_DAEMONIZED") != nullptr;
}
#endif
int ArchDaemonUnix::daemonize(const char *name, DaemonFunc const &func)
{
#ifdef __APPLE__
if (alreadyDaemonized())
return func(1, &name);
#endif
// fork so shell thinks we're done and so we're not a process
// group leader
switch (fork()) {
case -1:
// failed
throw ArchDaemonFailedException(errorToString(errno));
case 0:
// child
break;
default:
// parent exits
exit(0);
}
// become leader of a new session
setsid();
#ifndef __APPLE__
// NB: don't run chdir on apple; causes strange behaviour.
// chdir to root so we don't keep mounted filesystems points busy
// TODO: this is a bit of a hack - can we find a better solution?
if (int chdirErr = chdir("/"); chdirErr)
// NB: file logging actually isn't working at this point!
LOG_ERR("chdir error: %i", chdirErr);
#endif
// mask off permissions for any but owner
umask(077);
// close open files. we only expect stdin, stdout, stderr to be open.
close(0);
close(1);
close(2);
// attach file descriptors 0, 1, 2 to /dev/null so inadvertent use
// of standard I/O safely goes in the bit bucket.
open("/dev/null", O_RDONLY);
open("/dev/null", O_RDWR);
if (int dupErr = dup(1); dupErr < 0) {
// NB: file logging actually isn't working at this point!
LOG_ERR("dup error: %i", dupErr);
}
#ifdef __APPLE__
return execSelfNonDaemonized();
#endif
// invoke function
return func(1, &name);
}