moving 1.4 to trunk

src/lib/arch/CArchDaemonUnix.cpp

@@ -0,0 +1,127 @@
+/*
+ * synergy -- mouse and keyboard sharing utility
+ * Copyright (C) 2002 Chris Schoeneman, Nick Bolton, Sorin Sbarnea
+ * 
+ * This package is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * found in the file COPYING that should have accompanied this file.
+ * 
+ * This package is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "CArchDaemonUnix.h"
+#include "XArchUnix.h"
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <cstdlib>
+#include "CLog.h"
+
+//
+// CArchDaemonUnix
+//
+
+CArchDaemonUnix::CArchDaemonUnix()
+{
+	// do nothing
+}
+
+CArchDaemonUnix::~CArchDaemonUnix()
+{
+	// do nothing
+}
+
+
+#ifdef __APPLE__
+
+// In Mac OS X, fork()'d child processes can't use most APIs (the frameworks
+// that Synergy 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("_SYNERGY_DAEMONIZED", "", 1);
+	
+	execvp(selfArgv[0], selfArgv);
+	return 0;
+}
+
+bool alreadyDaemonized() {
+	return getenv("_SYNERGY_DAEMONIZED") != NULL;
+}
+
+#endif
+
+int
+CArchDaemonUnix::daemonize(const char* name, DaemonFunc 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 XArchDaemonFailed(new XArchEvalUnix(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?
+	int chdirErr = chdir("/");
+	if (chdirErr)
+		// NB: file logging actually isn't working at this point!
+		LOG((CLOG_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);
+	
+	int dupErr = dup(1);
+	if (dupErr)
+		// NB: file logging actually isn't working at this point!
+		LOG((CLOG_ERR "dup error: %i", dupErr));
+	
+#ifdef __APPLE__
+	return execSelfNonDaemonized();
+#endif
+	
+	// invoke function
+	return func(1, &name);
+}