Add a lockfile to the Tor data directory to avoid situations where two Tors... (f80ac31d) · Commits · David Goulet / Tor

ChangeLog

+4 −0

Original line number	Diff line number	Diff line
		@@ -3,6 +3,10 @@ Changes in version 0.2.1.6-alpha - 2008-09-xx
		- Fix compile on OpenBSD 4.4-current. Bugfix on 0.2.1.5-alpha.
		Reported by Tas.

		o Minor features:
		- Use a lockfile to make sure that two Tor processes are not
		simultaneously running with the same datadir.


		Changes in version 0.2.1.5-alpha - 2008-08-31
		o Major features:

configure.in

+1 −1

Original line number	Diff line number	Diff line
		@@ -324,7 +324,7 @@ AC_CHECK_HEADERS(netdb.h sys/ioctl.h sys/socket.h arpa/inet.h netinet/in.h pwd.h

		dnl These headers are not essential

		AC_CHECK_HEADERS(stdint.h sys/types.h inttypes.h sys/param.h sys/wait.h limits.h sys/limits.h netinet/in.h arpa/inet.h machine/limits.h syslog.h sys/time.h sys/resource.h inttypes.h utime.h sys/utime.h sys/mman.h netinet/in6.h malloc.h sys/syslimits.h malloc/malloc.h linux/types.h)
		AC_CHECK_HEADERS(stdint.h sys/types.h inttypes.h sys/param.h sys/wait.h limits.h sys/limits.h netinet/in.h arpa/inet.h machine/limits.h syslog.h sys/time.h sys/resource.h inttypes.h utime.h sys/utime.h sys/mman.h netinet/in6.h malloc.h sys/syslimits.h malloc/malloc.h linux/types.h sys/file.h)

		TOR_CHECK_PROTOTYPE(malloc_good_size, HAVE_MALLOC_GOOD_SIZE_PROTOTYPE,
		[#ifdef HAVE_MALLOC_H

src/common/compat.c

+75 −0

Original line number	Diff line number	Diff line
		@@ -26,6 +26,7 @@ const char compat_c_id[] =
		#ifdef MS_WINDOWS
		#include <process.h>
		#include <windows.h>
		#include <sys/locking.h>
		#endif

		#ifdef HAVE_UNAME
		@@ -98,6 +99,9 @@ const char compat_c_id[] =
		#ifdef HAVE_SYS_SYSLIMITS_H
		#include <sys/syslimits.h>
		#endif
		#ifdef HAVE_SYS_FILE_H
		#include <sys/file.h>
		#endif

		#ifdef USE_BSOCKETS
		#include <bsocket.h>
		@@ -488,6 +492,77 @@ touch_file(const char *fname)
		return 0;
		}

		struct tor_lockfile_t {
		char *filename;
		int fd;
		};

		tor_lockfile_t *
		tor_lockfile_lock(const char filename, int blocking, int locked_out)
		{
		tor_lockfile_t *result;
		int fd;
		*locked_out = 0;

		log_info(LD_FS, "Locking \"%s\"", filename);
		fd = open(filename, O_RDWR\|O_CREAT\|O_TRUNC, 0600);
		if (fd < 0) {
		log_warn(LD_FS,"Couldn't open \"%s\" for locking: %s", filename,
		strerror(errno));
		return NULL;
		}
		#ifdef WIN32
		_lseek(fd, 0, SEEK_SET);
		if (_locking(fd, blocking ? _LK_LOCK : _LK_NBLOCK, 0) < 0) {
		if (errno != EDEADLOCK)
		log_warn(LD_FS,"Couldn't lock \"%s\": %s", filename, strerror(errno));
		else
		*locked_out = 1;
		close(fd);
		return NULL;
		}
		#else
		if (flock(fd, LOCK_EX\|(blocking ? 0 : LOCK_NB)) < 0) {
		if (errno != EWOULDBLOCK)
		log_warn(LD_FS,"Couldn't lock \"%s\": %s", filename, strerror(errno));
		else
		*locked_out = 1;
		close(fd);
		return NULL;
		}
		#endif

		result = tor_malloc(sizeof(tor_lockfile_t));
		result->filename = tor_strdup(filename);
		result->fd = fd;
		return result;
		}

		void
		tor_lockfile_unlock(tor_lockfile_t *lockfile)
		{
		tor_assert(lockfile);

		log_info(LD_FS, "Unlocking \"%s\"", lockfile->filename);
		#ifdef WIN32
		_lseek(fd, 0, SEEK_SET);
		if (_locking(fd, _LK_UNLCK, 0) < 0) {
		log_warn(LD_FS,"Error unlocking \"%s\": %s", lockfile->filename,
		strerror(errno));
		}
		#else
		if (flock(lockfile->fd, LOCK_UN) < 0) {
		log_warn(LD_FS, "Error unlocking \"%s\": %s", lockfile->filename,
		strerror(errno));
		}
		#endif

		close(lockfile->fd);
		lockfile->fd = -1;
		tor_free(lockfile->filename);
		tor_free(lockfile);
		}

		#undef DEBUG_SOCKET_COUNTING
		#ifdef DEBUG_SOCKET_COUNTING
		/** A bitarray of all fds that should be passed to tor_socket_close(). Only

src/common/compat.h

+5 −0

Original line number	Diff line number	Diff line
		@@ -266,6 +266,11 @@ struct tm tor_gmtime_r(const time_t timep, struct tm *result);
		int replace_file(const char from, const char to);
		int touch_file(const char *fname);

		typedef struct tor_lockfile_t tor_lockfile_t;
		tor_lockfile_t tor_lockfile_lock(const char filename, int blocking,
		int *locked_out);
		void tor_lockfile_unlock(tor_lockfile_t *lockfile);

		#ifdef MS_WINDOWS
		#define PATH_SEPARATOR "\\"
		#else

src/or/config.c

+8 −3

Original line number	Diff line number	Diff line
		@@ -1172,6 +1172,11 @@ options_act(or_options_t *old_options)
		int running_tor = options->command == CMD_RUN_TOR;
		char *msg;

		if (running_tor && !have_lockfile()) {
		if (try_locking(options, 1) < 0)
		return -1;
		}

		if (consider_adding_dir_authorities(options, old_options) < 0)
		return -1;

		@@ -4883,10 +4888,10 @@ get_or_state(void)
		* Note: Consider using the get_datadir_fname* macros in or.h.
		*/
		char *
		get_datadir_fname2_suffix(const char sub1, const char sub2,
		options_get_datadir_fname2_suffix(or_options_t *options,
		const char sub1, const char sub2,
		const char *suffix)
		{
		or_options_t *options = get_options();
		char *fname = NULL;
		size_t len;
		tor_assert(options);