From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Date: Sat, 27 Dec 2008 19:07:33 +0000
Subject: Re: Revisiting threaded udevd
Message-Id: <49567CF5.4070807@tuffmail.co.uk>
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List-Id: <linux-hotplug.vger.kernel.org>
References: <494F7942.6060702@tuffmail.co.uk>
In-Reply-To: <494F7942.6060702@tuffmail.co.uk>
To: linux-hotplug@vger.kernel.org

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Scott James Remnant wrote:
> On Thu, 2008-12-25 at 17:36 +0000, Alan Jenkins wrote:
>  =20
> I think I got it right, maybe I missed something that was in your
> original patch?
>  =20

Could be. Either way, I found your problem:

udev-rules.c: In function =91udev_rules_apply_to_event=92:
udev-rules.c:2201: warning: passing argument 1 of =91udev_exec=92 from=20
incompatible pointer type

(The relevant line says event->udev, when it should probably be event->dev).

I'd already updated my original patches, so you might try them instead=20
(attached). They're not quite as well tested as before, but they should=20
still work. I'd be interested in any results of yours.

> The only vaguely unusual thing I was doing was running udevd in an
> existing booted system, and running udevadm trigger on that - so there
> would already have been udevdb entries for everything.
>  =20

That's exactly how I test.

Thanks
Alan

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diff --git a/udev/Makefile.am b/udev/Makefile.am
index 2d185f4..5739442 100644
--- a/udev/Makefile.am
+++ b/udev/Makefile.am
@@ -18,6 +18,7 @@ common_files = \
 	udev-event.c \
 	udev-node.c \
 	udev-rules.c \
+	udev-exec.c \
 	udev-util.c \
 	lib/libudev.h \
 	lib/libudev-private.h \
diff --git a/udev/test-udev.c b/udev/test-udev.c
index ff1c353..a26f308 100644
--- a/udev/test-udev.c
+++ b/udev/test-udev.c
@@ -60,6 +60,9 @@ int main(int argc, char *argv[])
 	info(udev, "version %s\n", VERSION);
 	udev_selinux_init(udev);
 
+	/* fork exec daemon before opening fds or changing signal handling */
+	udev_exec_init(udev);
+
 	/* set signal handlers */
 	memset(&act, 0x00, sizeof(act));
 	act.sa_handler = (void (*)(int)) sig_handler;
@@ -69,9 +72,6 @@ int main(int argc, char *argv[])
 	sigaction(SIGINT, &act, NULL);
 	sigaction(SIGTERM, &act, NULL);
 
-	/* trigger timeout to prevent hanging processes */
-	alarm(UDEV_EVENT_TIMEOUT);
-
 	action = getenv("ACTION");
 	devpath = getenv("DEVPATH");
 	subsystem = getenv("SUBSYSTEM");
@@ -99,10 +99,6 @@ int main(int argc, char *argv[])
 	event = udev_event_new(dev);
 	err = udev_event_execute_rules(event, rules);
 
-	/* rules may change/disable the timeout */
-	if (udev_device_get_event_timeout(dev) >= 0)
-		alarm(udev_device_get_event_timeout(dev));
-
 	if (err == 0 && !event->ignore_device && udev_get_run(udev))
 		udev_event_execute_run(event);
 
diff --git a/udev/udev-event.c b/udev/udev-event.c
index bc69239..f98638c 100644
--- a/udev/udev-event.c
+++ b/udev/udev-event.c
@@ -717,7 +717,7 @@ int udev_event_execute_run(struct udev_event *event)
 				       udev_device_get_seqnum(event->dev),
 				       program);
 			envp = udev_device_get_properties_envp(event->dev);
-			if (util_run_program(event->udev, program, envp, NULL, 0, NULL) != 0) {
+			if (udev_exec(event->dev, program, NULL, 0, NULL) != 0) {
 				if (!udev_list_entry_get_flag(list_entry))
 					err = -1;
 			}
diff --git a/udev/udev-exec.c b/udev/udev-exec.c
new file mode 100644
index 0000000..ae385bf
--- /dev/null
+++ b/udev/udev-exec.c
@@ -0,0 +1,592 @@
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <ctype.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <sys/wait.h>
+
+#include "udev.h"
+
+/*
+ * This daemon avoids problems with fork+exec from a multithreaded process -
+ * performance, and the need to close irrelevant file descriptors.
+ *
+ * TODO: Timeouts have not been tested
+ */
+
+#define MSG_SIZE 2048
+
+struct child {
+	struct udev_list_node node; /* must be first member */
+	pid_t pid;
+	int statuspipe; /* Pipe to write exit status to */
+};
+
+static int exec_msg(struct udev *udev, int sock, struct child **childp)
+{
+	struct msghdr msg;
+	struct iovec iov[1];
+	char msgbuf[MSG_SIZE];
+	int retval;
+	size_t count;
+	struct cmsghdr *cmsg;
+	char fdbuf[CMSG_SPACE(sizeof(int) * 4)];  /* ancillary data buffer */
+	int *fdptr = NULL;
+	int statuspipe;
+	int inpipe, outpipe, errpipe;
+	char *cmd, *env;
+	size_t cmdlen, envlen;
+	char program[UTIL_PATH_SIZE];
+	char *argv[(MSG_SIZE / 2) + 1];
+	char *envp[(MSG_SIZE / 4) + 1];
+	struct child *child;
+	pid_t pid;
+	int i;
+
+	memset(&msg, 0, sizeof(msg));
+	msg.msg_control = fdbuf;
+	msg.msg_controllen = sizeof(fdbuf);
+
+	iov[0].iov_base = msgbuf;
+	iov[0].iov_len = sizeof(msgbuf);
+	msg.msg_iov = iov;
+	msg.msg_iovlen = 1;
+
+	retval = recvmsg(sock, &msg, 0);
+	if (retval < 0) {
+		err(udev, "read error on socket (quitting): %m\n");
+		return -1;
+	}
+	count = retval;
+	if (count == 0) {
+		info(udev, "socket closed by udevd (quitting)\n");
+		return -1;
+	}
+
+	/* get file descriptors from message */
+	for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL; cmsg = CMSG_NXTHDR(&msg,cmsg)) {
+		if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) {
+			if (cmsg->cmsg_len < CMSG_LEN(sizeof(int) * 4)) {
+				err(udev, "message has too few pipes\n");
+				return 0;
+			}
+
+			fdptr = (int *) CMSG_DATA(cmsg);
+			inpipe = fdptr[0];
+			outpipe = fdptr[1];
+			errpipe = fdptr[2];
+			statuspipe = fdptr[3];
+			break;
+		}
+	}
+	if (fdptr == NULL) {
+		err(udev, "message lacks pipes\n");
+		return 0;
+	}
+
+	/* get command string and environment buffer from message */
+	cmd = &msgbuf[0];
+	cmdlen = strnlen(msgbuf, count);
+	if (cmdlen == count) {
+		err(udev, "message command lacks nul terminator\n");
+		return 0;
+	}
+	count -= (cmdlen + 1);
+	env = &msgbuf[cmdlen + 1];
+	envlen = count;
+
+	/* build argv from command */
+	info(udev, "'%s'\n", cmd);
+	i = 0;
+	if (strchr(cmd, ' ') != NULL) {
+		char *pos = cmd;
+
+		while (pos != NULL && pos[0] != '\0') {
+			if (pos[0] == '\'') {
+				/* do not separate quotes */
+				pos++;
+				argv[i] = strsep(&pos, "\'");
+				while (pos != NULL && pos[0] == ' ')
+					pos++;
+			} else {
+				argv[i] = strsep(&pos, " ");
+			}
+			dbg(udev, "arg[%i] '%s'\n", i, argv[i]);
+			i++;
+		}
+		argv[i] = NULL;
+	} else {
+		argv[0] = cmd;
+		argv[1] = NULL;
+	}
+
+	/* allow programs in /lib/udev/ to be called without the path */
+	if (strchr(argv[0], '/') == NULL) {
+		util_strlcpy(program, UDEV_PREFIX "/lib/udev/", sizeof(program));
+		util_strlcat(program, argv[0], sizeof(program));
+		argv[0] = program;
+	}
+
+	/* build envp from environment buffer */
+	i = 0;
+	if (envlen > 0) {
+		size_t off = 0;
+
+		while (off < envlen) {
+			envp[i] = &env[off];
+			off += strlen(&env[off]);
+			off++;
+			i++;
+		}
+		envp[i] = NULL;
+	} else {
+		envp[0] = NULL;
+	}
+
+
+	child = malloc(sizeof(struct child));
+	if (child == NULL)
+		return 0;
+
+	pid = fork();
+	switch(pid) {
+	case 0:
+		close(sock);
+		close(statuspipe);
+
+		dup2(inpipe, STDIN_FILENO);
+		close(inpipe);
+		dup2(outpipe, STDOUT_FILENO);
+		close(outpipe);
+		dup2(errpipe, STDERR_FILENO);
+		close(errpipe);
+
+		execve(argv[0], argv, envp);
+		if (errno == ENOENT || errno == ENOTDIR) {
+			/* may be on a filesytem which is not mounted right now */
+			info(udev, "program '%s' not found\n", argv[0]);
+		} else {
+			/* other problems */
+			err(udev, "exec of program '%s' failed\n", argv[0]);
+		}
+		_exit(1);
+	case -1:
+		err(udev, "fork of '%s' failed: %m\n", argv[0]);
+		free(child);
+		return 0;
+	default:
+		close(inpipe);
+		close(outpipe);
+		close(errpipe);
+
+		child->pid = pid;
+		child->statuspipe = statuspipe;
+
+		*childp = child;
+		return 0;
+	}
+}
+
+static int signal_pipe[2] = {-1, -1};
+
+static void asmlinkage sig_handler(int signum)
+{
+	/* write to pipe, which will wakeup select() */
+	write(signal_pipe[WRITE_END], "", 1);
+}
+
+static void udev_exec_daemon(struct udev *udev, int sock)
+{
+	struct udev_list_node child_list; /* Oldest first */
+	struct udev_list_node *child_loop;
+	struct sigaction act;
+	fd_set fds;
+	int maxfd;
+	int retval;
+
+	udev_list_init(&child_list);
+
+	/* setup signal handler pipe */
+	retval = pipe(signal_pipe);
+	if (retval < 0) {
+		err(udev, "error getting pipes: %m\n");
+		goto exit;
+	}
+
+	retval = fcntl(signal_pipe[WRITE_END], F_GETFL, 0);
+	if (retval < 0) {
+		err(udev, "error fcntl on pipe: %m\n");
+		goto exit;
+	}
+	retval = fcntl(signal_pipe[WRITE_END], F_SETFL, retval | O_NONBLOCK);
+	if (retval < 0) {
+		err(udev, "error fcntl on pipe: %m\n");
+		goto exit;
+	}
+
+	/* reset handlers to default */
+	memset(&act, 0x00, sizeof(struct sigaction));
+	sigemptyset(&act.sa_mask);
+	act.sa_handler = SIG_DFL;
+	sigaction(SIGINT, &act, NULL);
+	sigaction(SIGTERM, &act, NULL);
+	sigaction(SIGHUP, &act, NULL);
+
+	/* set SIGCHLD handler */
+	act.sa_handler = sig_handler;
+	act.sa_flags = SA_RESTART | SA_NOCLDSTOP;
+	sigaction(SIGCHLD, &act, NULL);
+
+	maxfd = sock;
+	maxfd = UDEV_MAX(maxfd, signal_pipe[READ_END]);
+	while(1) {
+		FD_ZERO(&fds);
+		FD_SET(sock, &fds);
+		FD_SET(signal_pipe[READ_END], &fds);
+
+		retval = select(maxfd+1, &fds, NULL, NULL, NULL);
+		if (retval < 0) {
+			if (errno == EINTR)
+				continue;
+
+			err(udev, "error in select: %m\n");
+			goto exit;
+		}
+
+		/* received a signal, clear our notification pipe */
+		if (FD_ISSET(signal_pipe[READ_END], &fds)) {
+			char buf[256];
+
+			read(signal_pipe[READ_END], &buf, sizeof(buf));
+		}
+
+		/* handle finished children */
+		while (1) {
+			pid_t pid;
+			int status;
+
+			pid = waitpid(-1, &status, WNOHANG);
+			if (pid <= 0)
+				break;
+
+			udev_list_node_foreach(child_loop, &child_list) {
+				struct child *child = (struct child *) child_loop;
+
+				if (child->pid == pid) {
+					write(child->statuspipe, &status, sizeof(status));
+					close(child->statuspipe);
+					udev_list_node_remove(&child->node);
+					free(child);
+					break;
+				}
+			}
+		}
+
+		/* read command and fork child */
+		if (FD_ISSET(sock, &fds)) {
+			struct child *new_child;
+
+			retval = exec_msg(udev, sock, &new_child);
+			if (retval == -1)
+				goto exit; /* read from socket failed - udevd has been terminated */
+
+			if (new_child)
+				udev_list_node_append(&new_child->node, &child_list);
+		}
+	}
+
+exit:
+	if (signal_pipe[READ_END] >= 0)
+		close(signal_pipe[READ_END]);
+	if (signal_pipe[WRITE_END] >= 0)
+		close(signal_pipe[WRITE_END]);
+	close(sock);
+
+	udev_unref(udev);
+	exit(1);
+}
+
+static int udev_exec_sock = -1;
+
+/* Use saved fd in case we re-create /dev/null */
+static int devnull = -1;
+
+int udev_exec_init(struct udev *udev)
+{
+	int sock[2];
+	int retval;
+	pid_t pid;
+
+	/* connection-oriented datagram socket -
+           daemon will die when we close it */
+	retval = socketpair(AF_LOCAL, SOCK_SEQPACKET, 0, sock);
+	if (retval != 0) {
+		err(udev, "error getting socket pair: %m\n");
+		return -1;
+	}
+
+	retval = fflush(NULL);
+	if (retval != 0) {
+		err(udev, "error flushing buffers before fork: %m\n");
+		return -1;
+	}
+
+	pid = fork();
+	switch(pid) {
+	case 0:
+		close(sock[0]);
+		logging_close();
+		logging_init("udev-exec");
+		setpriority(PRIO_PROCESS, 0, UDEV_PRIORITY);
+
+		udev_exec_daemon(udev, sock[1]);
+
+		/* not reached */
+		exit(1);
+	case -1:
+		err(udev, "failed to fork udev-exec daemon: %m\n");
+		return -1;
+	default:
+		udev_exec_sock = sock[0];
+		close(sock[1]);
+	}
+
+	devnull = open("/dev/null", O_RDWR);
+	if (devnull < 0) {
+		err(udev, "open /dev/null failed: %m\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+void udev_exec_cleanup(struct udev *udev)
+{
+	close(udev_exec_sock);
+	close(devnull);
+}
+
+int udev_exec(struct udev_device *dev, const char *command,
+	      char *result, size_t ressize, size_t *reslen)
+{
+	struct udev *udev = udev_device_get_udev(dev);
+	char **envp = udev_device_get_properties_envp(dev);
+	int outpipe[2] = {-1, -1};
+	int errpipe[2] = {-1, -1};
+	int statuspipe[2] = {-1, -1};
+	int status;
+	struct msghdr msg;
+	struct cmsghdr *cmsg;
+	char fdbuf[CMSG_SPACE(sizeof(int) * 4)];  /* ancillary data buffer */
+	int *fdptr;
+	struct iovec iov[2];
+	char envbuf[2048];
+	size_t bufpos = 0;
+	int i;
+	ssize_t count;
+	int maxfd;
+	struct timeval timeout;
+	size_t respos = 0;
+	int err = 0;
+
+	/* prepare pipes from child to parent */
+	if (result != NULL || udev_get_log_priority(udev) >= LOG_INFO) {
+		if (pipe(outpipe) != 0) {
+			err(udev, "pipe failed: %m\n");
+			return -1;
+		}
+	} else
+		outpipe[WRITE_END] = dup(devnull);
+
+	if (udev_get_log_priority(udev) >= LOG_INFO) {
+		if (pipe(errpipe) != 0) {
+			err(udev, "pipe failed: %m\n");
+			return -1;
+		}
+	} else
+		errpipe[WRITE_END] = dup(devnull);
+
+	if (pipe(statuspipe) != 0) {
+		err(udev, "pipe failed: %s\n", strerror(errno));
+		return -1;
+	}
+
+	/* child end of pipes are passed in ancillary data */
+	memset(&msg, 0, sizeof(msg));
+	msg.msg_control = fdbuf;
+	msg.msg_controllen = sizeof(fdbuf);
+	cmsg = CMSG_FIRSTHDR(&msg);
+	cmsg->cmsg_level = SOL_SOCKET;
+	cmsg->cmsg_type = SCM_RIGHTS;
+	cmsg->cmsg_len = CMSG_LEN(sizeof(int) * 4);
+	fdptr = (int *) CMSG_DATA(cmsg);
+	fdptr[0] = devnull;
+	fdptr[1] = outpipe[WRITE_END];
+	fdptr[2] = errpipe[WRITE_END];
+	fdptr[3] = statuspipe[WRITE_END];
+	msg.msg_controllen = cmsg->cmsg_len;
+
+	for (i = 0; envp[i] != NULL && bufpos < (sizeof(envbuf)); i++) {
+		bufpos += util_strlcpy(&envbuf[bufpos], envp[i], sizeof(envbuf) - bufpos);
+		bufpos++;
+	}
+	if (bufpos > sizeof(envbuf))
+		bufpos = sizeof(envbuf);
+
+	/* prepare message payload: command + environment */
+	iov[0].iov_base = (char *) command;
+	iov[0].iov_len = strlen(command) + 1;
+	iov[1].iov_base = envbuf;
+	iov[1].iov_len = bufpos;
+	msg.msg_iov = iov;
+	msg.msg_iovlen = 2;
+
+	/* dispatch request to daemon */
+	count = sendmsg(udev_exec_sock, &msg, 0);
+	if (count < 0) {
+		/* report error, but don't return without closing pipes */
+		err(udev, "failed to send message to exec daemon: %s\n", strerror(errno));
+	}
+
+	/* parent closes child ends of pipes */
+	close(outpipe[WRITE_END]);
+	close(errpipe[WRITE_END]);
+	close(statuspipe[WRITE_END]);
+
+	/* read child output */
+	if (udev_device_get_event_timeout(dev) >= 0)
+		timeout.tv_sec = udev_device_get_event_timeout(dev);
+	else
+		timeout.tv_sec = UDEV_EVENT_TIMEOUT;
+	timeout.tv_usec = 0;
+
+	maxfd = statuspipe[READ_END];
+	maxfd = UDEV_MAX(maxfd, outpipe[READ_END]);
+	maxfd = UDEV_MAX(maxfd, errpipe[READ_END]);
+	while (outpipe[READ_END] > 0 || errpipe[READ_END] > 0 || statuspipe[READ_END] > 0) {
+		int fdcount;
+		fd_set readfds;
+
+		FD_ZERO(&readfds);
+		if (outpipe[READ_END] > 0)
+			FD_SET(outpipe[READ_END], &readfds);
+		if (errpipe[READ_END] > 0)
+			FD_SET(errpipe[READ_END], &readfds);
+		if (statuspipe[READ_END] > 0)
+			FD_SET(statuspipe[READ_END], &readfds);
+		fdcount = select(maxfd+1, &readfds, NULL, NULL, &timeout);
+		if (fdcount < 0) {
+			if (errno == EINTR)
+				continue;
+			err = -1;
+			break;
+		}
+
+		if (timeout.tv_sec == 0 && timeout.tv_usec == 0) {
+			err = -1;
+			break;
+		}
+
+		/* get stdout */
+		if (outpipe[READ_END] > 0 && FD_ISSET(outpipe[READ_END], &readfds)) {
+			char inbuf[1024];
+			char *pos;
+			char *line;
+
+			count = read(outpipe[READ_END], inbuf, sizeof(inbuf)-1);
+			if (count <= 0) {
+				close(outpipe[READ_END]);
+				outpipe[READ_END] = -1;
+				if (count < 0) {
+					err(udev, "stdin read failed: %m\n");
+					err = -1;
+				}
+				continue;
+			}
+			inbuf[count] = '\0';
+
+			/* store result for rule processing */
+			if (result) {
+				if (respos + count < ressize) {
+					memcpy(&result[respos], inbuf, count);
+					respos += count;
+				} else {
+					err(udev, "ressize %ld too short\n", (long)ressize);
+					err = -1;
+				}
+			}
+			pos = inbuf;
+			while ((line = strsep(&pos, "\n")))
+				if (pos || line[0] != '\0')
+					info(udev, "'%s' (stdout) '%s'\n", command, line);
+		}
+
+		/* get stderr */
+		if (errpipe[READ_END] > 0 && FD_ISSET(errpipe[READ_END], &readfds)) {
+			char errbuf[1024];
+			char *pos;
+			char *line;
+
+			count = read(errpipe[READ_END], errbuf, sizeof(errbuf)-1);
+			if (count <= 0) {
+				close(errpipe[READ_END]);
+				errpipe[READ_END] = -1;
+				if (count < 0)
+					err(udev, "stderr read failed: %m\n");
+				continue;
+			}
+			errbuf[count] = '\0';
+			pos = errbuf;
+			while ((line = strsep(&pos, "\n")))
+				if (pos || line[0] != '\0')
+					info(udev, "'%s' (stderr) '%s'\n", command, line);
+		}
+
+		/* get exitstatus */
+		if (statuspipe[READ_END] > 0 && FD_ISSET(statuspipe[READ_END], &readfds)) {
+			count = read(statuspipe[READ_END], &status, sizeof(status));
+
+			if (count <= 0) {
+				if (count < 0)
+					err(udev, "'%s' error reading exit status: %m\n", command);
+				else
+					err(udev, "'%s' EOF on status pipe\n", command);
+				err = -1;
+
+				close(statuspipe[READ_END]);
+				statuspipe[READ_END] = -1;
+				continue;
+			}
+
+			if (WIFEXITED(status))
+				info(udev, "'%s' returned with status %i\n", command, WEXITSTATUS(status));
+			else
+				err(udev, "'%s' abnormal exit\n", command);
+			err = status;
+
+			close(statuspipe[READ_END]);
+			statuspipe[READ_END] = -1;
+		}
+	}
+	if (outpipe[READ_END] > 0)
+		close(outpipe[READ_END]);
+	if (outpipe[READ_END] > 0)
+		close(errpipe[READ_END]);
+	if (statuspipe[READ_END] > 0)
+		close(statuspipe[READ_END]);
+
+	/* return the childs stdout string */
+	if (result) {
+		result[respos] = '\0';
+		dbg(udev, "result='%s'\n", result);
+		if (reslen)
+			*reslen = respos;
+	}
+
+	return err;
+}
diff --git a/udev/udev-rules.c b/udev/udev-rules.c
index afd2e88..736f8ef 100644
--- a/udev/udev-rules.c
+++ b/udev/udev-rules.c
@@ -730,14 +730,11 @@ static int import_file_into_properties(struct udev_device *dev, const char *file
 
 static int import_program_into_properties(struct udev_device *dev, const char *program)
 {
-	struct udev *udev = udev_device_get_udev(dev);
-	char **envp;
 	char result[2048];
 	size_t reslen;
 	char *line;
 
-	envp = udev_device_get_properties_envp(dev);
-	if (util_run_program(udev, program, envp, result, sizeof(result), &reslen) != 0)
+	if (udev_exec(dev, program, result, sizeof(result), &reslen) != 0)
 		return -1;
 
 	line = result;
@@ -2190,19 +2187,17 @@ int udev_rules_apply_to_event(struct udev_rules *rules, struct udev_event *event
 		case TK_M_PROGRAM:
 			{
 				char program[UTIL_PATH_SIZE];
-				char **envp;
 				char result[UTIL_PATH_SIZE];
 
 				free(event->program_result);
 				event->program_result = NULL;
 				util_strlcpy(program, &rules->buf[cur->key.value_off], sizeof(program));
 				udev_event_apply_format(event, program, sizeof(program));
-				envp = udev_device_get_properties_envp(event->dev);
 				info(event->udev, "PROGRAM '%s' %s:%u\n",
 				     program,
 				     &rules->buf[rule->rule.filename_off],
 				     rule->rule.filename_line);
-				if (util_run_program(event->udev, program, envp, result, sizeof(result), NULL) != 0) {
+				if (udev_exec(event->dev, program, result, sizeof(result), NULL) != 0) {
 					if (cur->key.op != OP_NOMATCH)
 						goto nomatch;
 				} else {
diff --git a/udev/udev-util.c b/udev/udev-util.c
index 3d5eb76..be7ebfd 100644
--- a/udev/udev-util.c
+++ b/udev/udev-util.c
@@ -25,7 +25,6 @@
 #include <ctype.h>
 #include <pwd.h>
 #include <grp.h>
-#include <sys/wait.h>
 
 #include "udev.h"
 
@@ -238,215 +237,3 @@ int util_resolve_subsys_kernel(struct udev *udev, const char *string,
 	udev_device_unref(dev);
 	return 0;
 }
-
-int util_run_program(struct udev *udev, const char *command, char **envp,
-		     char *result, size_t ressize, size_t *reslen)
-{
-	int status;
-	int outpipe[2] = {-1, -1};
-	int errpipe[2] = {-1, -1};
-	pid_t pid;
-	char arg[UTIL_PATH_SIZE];
-	char program[UTIL_PATH_SIZE];
-	char *argv[(sizeof(arg) / 2) + 1];
-	int devnull;
-	int i;
-	int err = 0;
-
-	/* build argv from command */
-	util_strlcpy(arg, command, sizeof(arg));
-	i = 0;
-	if (strchr(arg, ' ') != NULL) {
-		char *pos = arg;
-
-		while (pos != NULL && pos[0] != '\0') {
-			if (pos[0] == '\'') {
-				/* do not separate quotes */
-				pos++;
-				argv[i] = strsep(&pos, "\'");
-				while (pos != NULL && pos[0] == ' ')
-					pos++;
-			} else {
-				argv[i] = strsep(&pos, " ");
-			}
-			dbg(udev, "arg[%i] '%s'\n", i, argv[i]);
-			i++;
-		}
-		argv[i] = NULL;
-	} else {
-		argv[0] = arg;
-		argv[1] = NULL;
-	}
-	info(udev, "'%s'\n", command);
-
-	/* prepare pipes from child to parent */
-	if (result != NULL || udev_get_log_priority(udev) >= LOG_INFO) {
-		if (pipe(outpipe) != 0) {
-			err(udev, "pipe failed: %m\n");
-			return -1;
-		}
-	}
-	if (udev_get_log_priority(udev) >= LOG_INFO) {
-		if (pipe(errpipe) != 0) {
-			err(udev, "pipe failed: %m\n");
-			return -1;
-		}
-	}
-
-	/* allow programs in /lib/udev/ to be called without the path */
-	if (strchr(argv[0], '/') == NULL) {
-		util_strlcpy(program, UDEV_PREFIX "/lib/udev/", sizeof(program));
-		util_strlcat(program, argv[0], sizeof(program));
-		argv[0] = program;
-	}
-
-	pid = fork();
-	switch(pid) {
-	case 0:
-		/* child closes parent ends of pipes */
-		if (outpipe[READ_END] > 0)
-			close(outpipe[READ_END]);
-		if (errpipe[READ_END] > 0)
-			close(errpipe[READ_END]);
-
-		/* discard child output or connect to pipe */
-		devnull = open("/dev/null", O_RDWR);
-		if (devnull > 0) {
-			dup2(devnull, STDIN_FILENO);
-			if (outpipe[WRITE_END] < 0)
-				dup2(devnull, STDOUT_FILENO);
-			if (errpipe[WRITE_END] < 0)
-				dup2(devnull, STDERR_FILENO);
-			close(devnull);
-		} else
-			err(udev, "open /dev/null failed: %m\n");
-		if (outpipe[WRITE_END] > 0) {
-			dup2(outpipe[WRITE_END], STDOUT_FILENO);
-			close(outpipe[WRITE_END]);
-		}
-		if (errpipe[WRITE_END] > 0) {
-			dup2(errpipe[WRITE_END], STDERR_FILENO);
-			close(errpipe[WRITE_END]);
-		}
-		execve(argv[0], argv, envp);
-		if (errno == ENOENT || errno == ENOTDIR) {
-			/* may be on a filesytem which is not mounted right now */
-			info(udev, "program '%s' not found\n", argv[0]);
-		} else {
-			/* other problems */
-			err(udev, "exec of program '%s' failed\n", argv[0]);
-		}
-		_exit(1);
-	case -1:
-		err(udev, "fork of '%s' failed: %m\n", argv[0]);
-		return -1;
-	default:
-		/* read from child if requested */
-		if (outpipe[READ_END] > 0 || errpipe[READ_END] > 0) {
-			ssize_t count;
-			size_t respos = 0;
-
-			/* parent closes child ends of pipes */
-			if (outpipe[WRITE_END] > 0)
-				close(outpipe[WRITE_END]);
-			if (errpipe[WRITE_END] > 0)
-				close(errpipe[WRITE_END]);
-
-			/* read child output */
-			while (outpipe[READ_END] > 0 || errpipe[READ_END] > 0) {
-				int fdcount;
-				fd_set readfds;
-
-				FD_ZERO(&readfds);
-				if (outpipe[READ_END] > 0)
-					FD_SET(outpipe[READ_END], &readfds);
-				if (errpipe[READ_END] > 0)
-					FD_SET(errpipe[READ_END], &readfds);
-				fdcount = select(UDEV_MAX(outpipe[READ_END], errpipe[READ_END])+1, &readfds, NULL, NULL, NULL);
-				if (fdcount < 0) {
-					if (errno == EINTR)
-						continue;
-					err = -1;
-					break;
-				}
-
-				/* get stdout */
-				if (outpipe[READ_END] > 0 && FD_ISSET(outpipe[READ_END], &readfds)) {
-					char inbuf[1024];
-					char *pos;
-					char *line;
-
-					count = read(outpipe[READ_END], inbuf, sizeof(inbuf)-1);
-					if (count <= 0) {
-						close(outpipe[READ_END]);
-						outpipe[READ_END] = -1;
-						if (count < 0) {
-							err(udev, "stdin read failed: %m\n");
-							err = -1;
-						}
-						continue;
-					}
-					inbuf[count] = '\0';
-
-					/* store result for rule processing */
-					if (result) {
-						if (respos + count < ressize) {
-							memcpy(&result[respos], inbuf, count);
-							respos += count;
-						} else {
-							err(udev, "ressize %ld too short\n", (long)ressize);
-							err = -1;
-						}
-					}
-					pos = inbuf;
-					while ((line = strsep(&pos, "\n")))
-						if (pos || line[0] != '\0')
-							info(udev, "'%s' (stdout) '%s'\n", argv[0], line);
-				}
-
-				/* get stderr */
-				if (errpipe[READ_END] > 0 && FD_ISSET(errpipe[READ_END], &readfds)) {
-					char errbuf[1024];
-					char *pos;
-					char *line;
-
-					count = read(errpipe[READ_END], errbuf, sizeof(errbuf)-1);
-					if (count <= 0) {
-						close(errpipe[READ_END]);
-						errpipe[READ_END] = -1;
-						if (count < 0)
-							err(udev, "stderr read failed: %m\n");
-						continue;
-					}
-					errbuf[count] = '\0';
-					pos = errbuf;
-					while ((line = strsep(&pos, "\n")))
-						if (pos || line[0] != '\0')
-							info(udev, "'%s' (stderr) '%s'\n", argv[0], line);
-				}
-			}
-			if (outpipe[READ_END] > 0)
-				close(outpipe[READ_END]);
-			if (errpipe[READ_END] > 0)
-				close(errpipe[READ_END]);
-
-			/* return the childs stdout string */
-			if (result) {
-				result[respos] = '\0';
-				dbg(udev, "result='%s'\n", result);
-				if (reslen)
-					*reslen = respos;
-			}
-		}
-		waitpid(pid, &status, 0);
-		if (WIFEXITED(status)) {
-			info(udev, "'%s' returned with status %i\n", argv[0], WEXITSTATUS(status));
-			if (WEXITSTATUS(status) != 0)
-				err = -1;
-		} else {
-			err(udev, "'%s' abnormal exit\n", command);
-			err = -1;
-		}
-	}
-	return err;
-}
diff --git a/udev/udev.h b/udev/udev.h
index ea8c8d9..0bd6ca1 100644
--- a/udev/udev.h
+++ b/udev/udev.h
@@ -35,6 +35,9 @@
 #define READ_END				0
 #define WRITE_END				1
 
+#define UDEVD_PRIORITY			-4 /* nice level for daemon */
+#define UDEV_PRIORITY			-2 /* nice level for programs run by daemon*/
+
 static inline void logging_init(const char *program_name)
 {
 	openlog(program_name, LOG_PID | LOG_CONS, LOG_DAEMON);
@@ -100,14 +103,18 @@ extern int udev_node_add(struct udev_device *dev, mode_t mode, uid_t uid, gid_t
 extern int udev_node_remove(struct udev_device *dev, int test);
 extern void udev_node_update_old_links(struct udev_device *dev, struct udev_device *dev_old, int test);
 
+/* udev-exec.c */
+extern int udev_exec_init(struct udev *udev);
+extern void udev_exec_cleanup(struct udev *udev);
+extern int udev_exec(struct udev_device *dev, const char *command,
+		     char *result, size_t ressize, size_t *reslen);
+
 /* udev-util.c */
 extern int util_create_path(struct udev *udev, const char *path);
 extern int util_delete_path(struct udev *udev, const char *path);
 extern int util_unlink_secure(struct udev *udev, const char *filename);
 extern uid_t util_lookup_user(struct udev *udev, const char *user);
 extern gid_t util_lookup_group(struct udev *udev, const char *group);
-extern int util_run_program(struct udev *udev, const char *command, char **envp,
-			    char *result, size_t ressize, size_t *reslen);
 extern int util_resolve_subsys_kernel(struct udev *udev, const char *string,
 				      char *result, size_t maxsize, int read_value);
 
diff --git a/udev/udevd.c b/udev/udevd.c
index bfd7323..d57006b 100644
--- a/udev/udevd.c
+++ b/udev/udevd.c
@@ -214,16 +214,9 @@ static void event_fork(struct udev_event *event)
 		sigaction(SIGCHLD, &act, NULL);
 		sigaction(SIGHUP, &act, NULL);
 
-		/* set timeout to prevent hanging processes */
-		alarm(UDEV_EVENT_TIMEOUT);
-
 		/* apply rules, create node, symlinks */
 		err = udev_event_execute_rules(event, rules);
 
-		/* rules may change/disable the timeout */
-		if (udev_device_get_event_timeout(event->dev) >= 0)
-			alarm(udev_device_get_event_timeout(event->dev));
-
 		/* execute RUN= */
 		if (err == 0 && !event->ignore_device && udev_get_run(event->udev))
 			udev_event_execute_run(event);
@@ -706,6 +699,13 @@ int main(int argc, char *argv[])
 	if (write(STDERR_FILENO, 0, 0) < 0)
 		dup2(fd, STDERR_FILENO);
 
+	chdir("/");
+	umask(022);
+	setsid();
+
+	/* fork exec daemon before opening more fds or changing signal handling */
+	udev_exec_init(udev);
+
 	/* init control socket, bind() ensures, that only one udevd instance is running */
 	udev_ctrl = udev_ctrl_new_from_socket(udev, UDEV_CTRL_SOCK_PATH);
 	if (udev_ctrl == NULL) {
@@ -799,10 +799,6 @@ int main(int argc, char *argv[])
 	/* set scheduling priority for the daemon */
 	setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
 
-	chdir("/");
-	umask(022);
-	setsid();
-
 	/* OOM_DISABLE == -17 */
 	fd = open("/proc/self/oom_adj", O_RDWR);
 	if (fd < 0)
@@ -986,6 +982,7 @@ exit:
 	if (inotify_fd >= 0)
 		close(inotify_fd);
 	udev_monitor_unref(kernel_monitor);
+	udev_exec_cleanup(udev);
 	udev_selinux_exit(udev);
 	udev_unref(udev);
 	logging_close();

--------------050607090004090203040301
Content-Type: text/plain;
 name="vfork"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="vfork"

diff --git a/udev/udev-exec.c b/udev/udev-exec.c
index ae385bf..6ad4fc1 100644
--- a/udev/udev-exec.c
+++ b/udev/udev-exec.c
@@ -153,7 +153,9 @@ static int exec_msg(struct udev *udev, int sock, struct child **childp)
 	if (child == NULL)
 		return 0;
 
-	pid = fork();
+	/* CAUTION.  Child may (or may not) share memory - including stack.
+	   Child should do the minimum necessary before exec() */
+	pid = vfork();
 	switch(pid) {
 	case 0:
 		close(sock);

--------------050607090004090203040301
Content-Type: text/plain;
 name="build_pthreads"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="build_pthreads"

diff --git a/acx_pthread.m4 b/acx_pthread.m4
new file mode 100644
index 0000000..eb09f5a
--- /dev/null
+++ b/acx_pthread.m4
@@ -0,0 +1,275 @@
+# ===========================================================================
+#              http://autoconf-archive.cryp.to/acx_pthread.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   ACX_PTHREAD([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]])
+#
+# DESCRIPTION
+#
+#   This macro figures out how to build C programs using POSIX threads. It
+#   sets the PTHREAD_LIBS output variable to the threads library and linker
+#   flags, and the PTHREAD_CFLAGS output variable to any special C compiler
+#   flags that are needed. (The user can also force certain compiler
+#   flags/libs to be tested by setting these environment variables.)
+#
+#   Also sets PTHREAD_CC to any special C compiler that is needed for
+#   multi-threaded programs (defaults to the value of CC otherwise). (This
+#   is necessary on AIX to use the special cc_r compiler alias.)
+#
+#   NOTE: You are assumed to not only compile your program with these flags,
+#   but also link it with them as well. e.g. you should link with
+#   $PTHREAD_CC $CFLAGS $PTHREAD_CFLAGS $LDFLAGS ... $PTHREAD_LIBS $LIBS
+#
+#   If you are only building threads programs, you may wish to use these
+#   variables in your default LIBS, CFLAGS, and CC:
+#
+#          LIBS="$PTHREAD_LIBS $LIBS"
+#          CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
+#          CC="$PTHREAD_CC"
+#
+#   In addition, if the PTHREAD_CREATE_JOINABLE thread-attribute constant
+#   has a nonstandard name, defines PTHREAD_CREATE_JOINABLE to that name
+#   (e.g. PTHREAD_CREATE_UNDETACHED on AIX).
+#
+#   ACTION-IF-FOUND is a list of shell commands to run if a threads library
+#   is found, and ACTION-IF-NOT-FOUND is a list of commands to run it if it
+#   is not found. If ACTION-IF-FOUND is not specified, the default action
+#   will define HAVE_PTHREAD.
+#
+#   Please let the authors know if this macro fails on any platform, or if
+#   you have any other suggestions or comments. This macro was based on work
+#   by SGJ on autoconf scripts for FFTW (http://www.fftw.org/) (with help
+#   from M. Frigo), as well as ac_pthread and hb_pthread macros posted by
+#   Alejandro Forero Cuervo to the autoconf macro repository. We are also
+#   grateful for the helpful feedback of numerous users.
+#
+# LAST MODIFICATION
+#
+#   2008-04-12
+#
+# COPYLEFT
+#
+#   Copyright (c) 2008 Steven G. Johnson <stevenj@alum.mit.edu>
+#
+#   This program is free software: you can redistribute it and/or modify it
+#   under the terms of the GNU General Public License as published by the
+#   Free Software Foundation, either version 3 of the License, or (at your
+#   option) any later version.
+#
+#   This program 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/>.
+#
+#   As a special exception, the respective Autoconf Macro's copyright owner
+#   gives unlimited permission to copy, distribute and modify the configure
+#   scripts that are the output of Autoconf when processing the Macro. You
+#   need not follow the terms of the GNU General Public License when using
+#   or distributing such scripts, even though portions of the text of the
+#   Macro appear in them. The GNU General Public License (GPL) does govern
+#   all other use of the material that constitutes the Autoconf Macro.
+#
+#   This special exception to the GPL applies to versions of the Autoconf
+#   Macro released by the Autoconf Macro Archive. When you make and
+#   distribute a modified version of the Autoconf Macro, you may extend this
+#   special exception to the GPL to apply to your modified version as well.
+
+AC_DEFUN([ACX_PTHREAD], [
+AC_REQUIRE([AC_CANONICAL_HOST])
+AC_LANG_SAVE
+AC_LANG_C
+acx_pthread_ok=no
+
+# We used to check for pthread.h first, but this fails if pthread.h
+# requires special compiler flags (e.g. on True64 or Sequent).
+# It gets checked for in the link test anyway.
+
+# First of all, check if the user has set any of the PTHREAD_LIBS,
+# etcetera environment variables, and if threads linking works using
+# them:
+if test x"$PTHREAD_LIBS$PTHREAD_CFLAGS" != x; then
+        save_CFLAGS="$CFLAGS"
+        CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
+        save_LIBS="$LIBS"
+        LIBS="$PTHREAD_LIBS $LIBS"
+        AC_MSG_CHECKING([for pthread_join in LIBS=$PTHREAD_LIBS with CFLAGS=$PTHREAD_CFLAGS])
+        AC_TRY_LINK_FUNC(pthread_join, acx_pthread_ok=yes)
+        AC_MSG_RESULT($acx_pthread_ok)
+        if test x"$acx_pthread_ok" = xno; then
+                PTHREAD_LIBS=""
+                PTHREAD_CFLAGS=""
+        fi
+        LIBS="$save_LIBS"
+        CFLAGS="$save_CFLAGS"
+fi
+
+# We must check for the threads library under a number of different
+# names; the ordering is very important because some systems
+# (e.g. DEC) have both -lpthread and -lpthreads, where one of the
+# libraries is broken (non-POSIX).
+
+# Create a list of thread flags to try.  Items starting with a "-" are
+# C compiler flags, and other items are library names, except for "none"
+# which indicates that we try without any flags at all, and "pthread-config"
+# which is a program returning the flags for the Pth emulation library.
+
+acx_pthread_flags="pthreads none -Kthread -kthread lthread -pthread -pthreads -mthreads pthread --thread-safe -mt pthread-config"
+
+# The ordering *is* (sometimes) important.  Some notes on the
+# individual items follow:
+
+# pthreads: AIX (must check this before -lpthread)
+# none: in case threads are in libc; should be tried before -Kthread and
+#       other compiler flags to prevent continual compiler warnings
+# -Kthread: Sequent (threads in libc, but -Kthread needed for pthread.h)
+# -kthread: FreeBSD kernel threads (preferred to -pthread since SMP-able)
+# lthread: LinuxThreads port on FreeBSD (also preferred to -pthread)
+# -pthread: Linux/gcc (kernel threads), BSD/gcc (userland threads)
+# -pthreads: Solaris/gcc
+# -mthreads: Mingw32/gcc, Lynx/gcc
+# -mt: Sun Workshop C (may only link SunOS threads [-lthread], but it
+#      doesn't hurt to check since this sometimes defines pthreads too;
+#      also defines -D_REENTRANT)
+#      ... -mt is also the pthreads flag for HP/aCC
+# pthread: Linux, etcetera
+# --thread-safe: KAI C++
+# pthread-config: use pthread-config program (for GNU Pth library)
+
+case "${host_cpu}-${host_os}" in
+        *solaris*)
+
+        # On Solaris (at least, for some versions), libc contains stubbed
+        # (non-functional) versions of the pthreads routines, so link-based
+        # tests will erroneously succeed.  (We need to link with -pthreads/-mt/
+        # -lpthread.)  (The stubs are missing pthread_cleanup_push, or rather
+        # a function called by this macro, so we could check for that, but
+        # who knows whether they'll stub that too in a future libc.)  So,
+        # we'll just look for -pthreads and -lpthread first:
+
+        acx_pthread_flags="-pthreads pthread -mt -pthread $acx_pthread_flags"
+        ;;
+esac
+
+if test x"$acx_pthread_ok" = xno; then
+for flag in $acx_pthread_flags; do
+
+        case $flag in
+                none)
+                AC_MSG_CHECKING([whether pthreads work without any flags])
+                ;;
+
+                -*)
+                AC_MSG_CHECKING([whether pthreads work with $flag])
+                PTHREAD_CFLAGS="$flag"
+                ;;
+
+		pthread-config)
+		AC_CHECK_PROG(acx_pthread_config, pthread-config, yes, no)
+		if test x"$acx_pthread_config" = xno; then continue; fi
+		PTHREAD_CFLAGS="`pthread-config --cflags`"
+		PTHREAD_LIBS="`pthread-config --ldflags` `pthread-config --libs`"
+		;;
+
+                *)
+                AC_MSG_CHECKING([for the pthreads library -l$flag])
+                PTHREAD_LIBS="-l$flag"
+                ;;
+        esac
+
+        save_LIBS="$LIBS"
+        save_CFLAGS="$CFLAGS"
+        LIBS="$PTHREAD_LIBS $LIBS"
+        CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
+
+        # Check for various functions.  We must include pthread.h,
+        # since some functions may be macros.  (On the Sequent, we
+        # need a special flag -Kthread to make this header compile.)
+        # We check for pthread_join because it is in -lpthread on IRIX
+        # while pthread_create is in libc.  We check for pthread_attr_init
+        # due to DEC craziness with -lpthreads.  We check for
+        # pthread_cleanup_push because it is one of the few pthread
+        # functions on Solaris that doesn't have a non-functional libc stub.
+        # We try pthread_create on general principles.
+        AC_TRY_LINK([#include <pthread.h>],
+                    [pthread_t th; pthread_join(th, 0);
+                     pthread_attr_init(0); pthread_cleanup_push(0, 0);
+                     pthread_create(0,0,0,0); pthread_cleanup_pop(0); ],
+                    [acx_pthread_ok=yes])
+
+        LIBS="$save_LIBS"
+        CFLAGS="$save_CFLAGS"
+
+        AC_MSG_RESULT($acx_pthread_ok)
+        if test "x$acx_pthread_ok" = xyes; then
+                break;
+        fi
+
+        PTHREAD_LIBS=""
+        PTHREAD_CFLAGS=""
+done
+fi
+
+# Various other checks:
+if test "x$acx_pthread_ok" = xyes; then
+        save_LIBS="$LIBS"
+        LIBS="$PTHREAD_LIBS $LIBS"
+        save_CFLAGS="$CFLAGS"
+        CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
+
+        # Detect AIX lossage: JOINABLE attribute is called UNDETACHED.
+	AC_MSG_CHECKING([for joinable pthread attribute])
+	attr_name=unknown
+	for attr in PTHREAD_CREATE_JOINABLE PTHREAD_CREATE_UNDETACHED; do
+	    AC_TRY_LINK([#include <pthread.h>], [int attr=$attr; return attr;],
+                        [attr_name=$attr; break])
+	done
+        AC_MSG_RESULT($attr_name)
+        if test "$attr_name" != PTHREAD_CREATE_JOINABLE; then
+            AC_DEFINE_UNQUOTED(PTHREAD_CREATE_JOINABLE, $attr_name,
+                               [Define to necessary symbol if this constant
+                                uses a non-standard name on your system.])
+        fi
+
+        AC_MSG_CHECKING([if more special flags are required for pthreads])
+        flag=no
+        case "${host_cpu}-${host_os}" in
+            *-aix* | *-freebsd* | *-darwin*) flag="-D_THREAD_SAFE";;
+            *solaris* | *-osf* | *-hpux*) flag="-D_REENTRANT";;
+        esac
+        AC_MSG_RESULT(${flag})
+        if test "x$flag" != xno; then
+            PTHREAD_CFLAGS="$flag $PTHREAD_CFLAGS"
+        fi
+
+        LIBS="$save_LIBS"
+        CFLAGS="$save_CFLAGS"
+
+        # More AIX lossage: must compile with xlc_r or cc_r
+	if test x"$GCC" != xyes; then
+          AC_CHECK_PROGS(PTHREAD_CC, xlc_r cc_r, ${CC})
+        else
+          PTHREAD_CC=$CC
+	fi
+else
+        PTHREAD_CC="$CC"
+fi
+
+AC_SUBST(PTHREAD_LIBS)
+AC_SUBST(PTHREAD_CFLAGS)
+AC_SUBST(PTHREAD_CC)
+
+# Finally, execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND:
+if test x"$acx_pthread_ok" = xyes; then
+        ifelse([$1],,AC_DEFINE(HAVE_PTHREAD,1,[Define if you have POSIX threads libraries and header files.]),[$1])
+        :
+else
+        acx_pthread_ok=no
+        $2
+fi
+AC_LANG_RESTORE
+])dnl ACX_PTHREAD
diff --git a/configure.ac b/configure.ac
index 6e98f37..7f1c901 100644
--- a/configure.ac
+++ b/configure.ac
@@ -9,6 +9,8 @@ AC_DISABLE_STATIC
 AC_SYS_LARGEFILE
 AC_PROG_LIBTOOL
 
+sinclude(acx_pthread.m4)
+
 dnl /* libudev version */
 LIBUDEV_LT_CURRENT=0
 LIBUDEV_LT_REVISION=3
@@ -25,6 +27,8 @@ AC_SUBST(VOLID_LT_CURRENT)
 AC_SUBST(VOLID_LT_REVISION)
 AC_SUBST(VOLID_LT_AGE)
 
+ACX_PTHREAD(AC_DEFINE(HAVE_PTHREAD), AC_MSG_FAILURE([pthreads unavailable]))
+
 AC_PATH_PROG([XSLTPROC], [xsltproc])
 
 AC_CHECK_LIB(c, inotify_init,
diff --git a/udev/Makefile.am b/udev/Makefile.am
index 2b35bd9..9368e9b 100644
--- a/udev/Makefile.am
+++ b/udev/Makefile.am
@@ -1,5 +1,9 @@
 include $(top_srcdir)/Makefile.am.inc
 
+LIBS += $(PTHREAD_LIBS)
+CFLAGS += $(PTHREAD_CFLAGS)
+CC=$(PTHREAD_CC)
+
 SUBDIRS = \
 	lib
 

--------------050607090004090203040301
Content-Type: text/plain;
 name="use_pthreads"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="use_pthreads"

diff --git a/udev/test-udev.c b/udev/test-udev.c
index a26f308..ce7e3af 100644
--- a/udev/test-udev.c
+++ b/udev/test-udev.c
@@ -107,6 +107,7 @@ int main(int argc, char *argv[])
 fail:
 	udev_rules_unref(rules);
 exit:
+	udev_exec_cleanup(udev);
 	udev_selinux_exit(udev);
 	udev_unref(udev);
 	if (err != 0)
diff --git a/udev/udev.h b/udev/udev.h
index 0bd6ca1..887f92d 100644
--- a/udev/udev.h
+++ b/udev/udev.h
@@ -67,7 +67,7 @@ struct udev_event {
 	uid_t uid;
 	gid_t gid;
 	struct udev_list_node run_list;
-	pid_t pid;
+	pthread_t thread;
 	int exitstatus;
 	time_t queue_time;
 	unsigned long long int delaying_seqnum;
@@ -80,6 +80,7 @@ struct udev_event {
 	unsigned int ignore_device:1;
 	unsigned int trace:1;
 	unsigned int test:1;
+	unsigned int running:1;
 };
 
 /* udev-rules.c */
diff --git a/udev/udevd.c b/udev/udevd.c
index d57006b..785e4c5 100644
--- a/udev/udevd.c
+++ b/udev/udevd.c
@@ -29,18 +29,17 @@
 #include <getopt.h>
 #include <dirent.h>
 #include <sys/select.h>
-#include <sys/wait.h>
 #include <sys/stat.h>
 #include <sys/ioctl.h>
+#include <sys/time.h>
+#include <sys/resource.h>
 #ifdef HAVE_INOTIFY
 #include <sys/inotify.h>
 #endif
+#include <pthread.h>
 
 #include "udev.h"
 
-#define UDEVD_PRIORITY			-4
-#define UDEV_PRIORITY			-2
-
 /* maximum limit of forked childs */
 #define UDEVD_MAX_CHILDS		256
 
@@ -64,7 +63,7 @@ static struct udev_ctrl *udev_ctrl;
 static struct udev_monitor *kernel_monitor;
 static int inotify_fd = -1;
 static int signal_pipe[2] = {-1, -1};
-static volatile int sigchilds_waiting;
+static int event_done_pipe[2] = {-1, -1};
 static volatile int udev_exit;
 static volatile int reload_config;
 static int run_exec_q;
@@ -73,6 +72,8 @@ static int max_childs;
 static int childs;
 static struct udev_list_node event_list;
 
+pthread_attr_t thread_attr;
+
 enum event_state {
 	EVENT_QUEUED,
 	EVENT_FINISHED,
@@ -167,80 +168,71 @@ static void event_queue_delete(struct udev_event *event)
 	udev_event_unref(event);
 }
 
-static void asmlinkage event_sig_handler(int signum)
+static int event_run(struct udev_event *event)
 {
-	if (signum == SIGALRM)
-		exit(1);
+	int err;
+
+	/* apply rules, create node, symlinks */
+	err = udev_event_execute_rules(event, rules);
+
+	/* execute RUN= */
+	if (err == 0 && !event->ignore_device && udev_get_run(event->udev))
+		udev_event_execute_run(event);
+	info(event->udev, "seq %llu exit with %i\n", udev_device_get_seqnum(event->dev), err);
+
+	return err;
 }
 
-static void event_fork(struct udev_event *event)
+static void *event_run_pthread(void *arg)
 {
-	pid_t pid;
-	struct sigaction act;
+	struct udev_event *event = arg;
 	int err;
 
-	if (debug_trace) {
-		event->trace = 1;
-		fprintf(stderr, "fork %s (%llu)\n",
-		       udev_device_get_syspath(event->dev),
-		       udev_device_get_seqnum(event->dev));
-	}
-
-	pid = fork();
-	switch (pid) {
-	case 0:
-		/* child */
-		udev_monitor_unref(kernel_monitor);
-		udev_ctrl_unref(udev_ctrl);
-		if (inotify_fd >= 0)
-			close(inotify_fd);
-		close(signal_pipe[READ_END]);
-		close(signal_pipe[WRITE_END]);
-		logging_close();
-		logging_init("udevd-event");
-		setpriority(PRIO_PROCESS, 0, UDEV_PRIORITY);
-
-		/* set signal handlers */
-		memset(&act, 0x00, sizeof(act));
-		act.sa_handler = (void (*)(int)) event_sig_handler;
-		sigemptyset (&act.sa_mask);
-		act.sa_flags = 0;
-		sigaction(SIGALRM, &act, NULL);
-
-		/* reset to default */
-		act.sa_handler = SIG_DFL;
-		sigaction(SIGINT, &act, NULL);
-		sigaction(SIGTERM, &act, NULL);
-		sigaction(SIGCHLD, &act, NULL);
-		sigaction(SIGHUP, &act, NULL);
-
-		/* apply rules, create node, symlinks */
-		err = udev_event_execute_rules(event, rules);
-
-		/* execute RUN= */
-		if (err == 0 && !event->ignore_device && udev_get_run(event->udev))
-			udev_event_execute_run(event);
-
-		info(event->udev, "seq %llu exit with %i\n", udev_device_get_seqnum(event->dev), err);
-		logging_close();
-		if (err != 0)
-			exit(1);
-		exit(0);
-	case -1:
-		err(event->udev, "fork of child failed: %m\n");
+	err = event_run(event);
+
+	/* write to pipe, which will wakeup select() in our mainloop */
+	write(event_done_pipe[WRITE_END], &event, sizeof(struct udev_event *));
+
+	return (void *) (uintptr_t) err;
+}
+
+static void event_thread_create(struct udev_event *event)
+{
+	if (pthread_create(&event->thread, &thread_attr, event_run_pthread, event) != 0) {
+		err(event->udev, "create thread failed: %m\n");
 		event_queue_delete(event);
-		break;
-	default:
-		/* get SIGCHLD in main loop */
-		info(event->udev, "seq %llu forked, pid [%d], '%s' '%s', %ld seconds old\n",
-		     udev_device_get_seqnum(event->dev),
-		     pid,
-		     udev_device_get_action(event->dev),
-		     udev_device_get_subsystem(event->dev),
-		     time(NULL) - event->queue_time);
-		event->pid = pid;
-		childs++;
+		return;
+	}
+
+	event->running = 1;
+
+	info(event->udev, "seq %llu created, '%s' '%s', %ld seconds old\n",
+	     udev_device_get_seqnum(event->dev),
+	     udev_device_get_action(event->dev),
+	     udev_device_get_subsystem(event->dev),
+	     time(NULL) - event->queue_time);
+}
+
+static int event_thread_join(struct udev_event *event)
+{
+	void *result;
+	int err;
+
+	err = pthread_join(event->thread, &result);
+	if (err) {
+		err(event->udev, "failed to retrieve thread return value: %m\n");
+		return -1;
 	}
+
+	return (int) (uintptr_t) result;
+}
+
+static void event_thread_kill(struct udev_event *event)
+{
+	pthread_kill(event->thread, SIGTERM);
+
+	/* Make sure thread has died before we return */
+	event_thread_join(event);
 }
 
 static void event_queue_insert(struct udev_event *event)
@@ -272,7 +264,7 @@ static void event_queue_insert(struct udev_event *event)
 
 	/* run all events with a timeout set immediately */
 	if (udev_device_get_timeout(event->dev) > 0) {
-		event_fork(event);
+		event_thread_create(event);
 		return;
 	}
 }
@@ -413,7 +405,7 @@ static void event_queue_manager(struct udev *udev)
 			break;
 		}
 
-		if (loop_event->pid != 0)
+		if (loop_event->running)
 			continue;
 
 		/* do not start event if parent or child event is still running */
@@ -424,7 +416,7 @@ static void event_queue_manager(struct udev *udev)
 			continue;
 		}
 
-		event_fork(loop_event);
+		event_thread_create(loop_event);
 		dbg(udev, "moved seq %llu to running list\n", udev_device_get_seqnum(loop_event->dev));
 	}
 }
@@ -502,11 +494,8 @@ static void asmlinkage sig_handler(int signum)
 	switch (signum) {
 		case SIGINT:
 		case SIGTERM:
-			udev_exit = 1;
-			break;
 		case SIGCHLD:
-			/* set flag, then write to pipe if needed */
-			sigchilds_waiting = 1;
+			udev_exit = 1;
 			break;
 		case SIGHUP:
 			reload_config = 1;
@@ -517,50 +506,17 @@ static void asmlinkage sig_handler(int signum)
 	write(signal_pipe[WRITE_END], "", 1);
 }
 
-static void udev_done(int pid, int exitstatus)
+static void udev_done(struct udev_event *event)
 {
-	struct udev_list_node *loop;
+	event->exitstatus = event_thread_join(event);
+	info(event->udev, "seq %llu cleanup, status %i, %ld seconds old\n",
+	     udev_device_get_seqnum(event->dev),
+	     event->exitstatus, time(NULL) - event->queue_time);
 
-	/* find event associated with pid and delete it */
-	udev_list_node_foreach(loop, &event_list) {
-		struct udev_event *loop_event = node_to_event(loop);
-
-		if (loop_event->pid == pid) {
-			info(loop_event->udev, "seq %llu cleanup, pid [%d], status %i, %ld seconds old\n",
-			     udev_device_get_seqnum(loop_event->dev), loop_event->pid,
-			     exitstatus, time(NULL) - loop_event->queue_time);
-			loop_event->exitstatus = exitstatus;
-			if (debug_trace)
-				fprintf(stderr, "exit %s (%llu)\n",
-				       udev_device_get_syspath(loop_event->dev),
-				       udev_device_get_seqnum(loop_event->dev));
-			event_queue_delete(loop_event);
-			childs--;
-
-			/* there may be dependent events waiting */
-			run_exec_q = 1;
-			return;
-		}
-	}
-}
-
-static void reap_sigchilds(void)
-{
-	pid_t pid;
-	int status;
+	event_queue_delete(event);
 
-	while (1) {
-		pid = waitpid(-1, &status, WNOHANG);
-		if (pid <= 0)
-			break;
-		if (WIFEXITED(status))
-			status = WEXITSTATUS(status);
-		else if (WIFSIGNALED(status))
-			status = WTERMSIG(status) + 128;
-		else
-			status = 0;
-		udev_done(pid, status);
-	}
+	/* there may be events waiting with the same devpath */
+	run_exec_q = 1;
 }
 
 static void cleanup_queue_dir(struct udev *udev)
@@ -629,6 +585,8 @@ int main(int argc, char *argv[])
 	int err;
 	int fd;
 	struct sigaction act;
+	int pagesize;
+	int stacksize;
 	fd_set readfds;
 	const char *value;
 	int daemonize = 0;
@@ -736,6 +694,11 @@ int main(int argc, char *argv[])
 		err(udev, "error getting pipes: %m\n");
 		goto exit;
 	}
+	err = pipe(event_done_pipe);
+	if (err < 0) {
+		err(udev, "error getting pipes: %m\n");
+		goto exit;
+	}
 
 	err = fcntl(signal_pipe[READ_END], F_GETFL, 0);
 	if (err < 0) {
@@ -799,6 +762,29 @@ int main(int argc, char *argv[])
 	/* set scheduling priority for the daemon */
 	setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
 
+	pthread_attr_init(&thread_attr);
+
+	/* To create many threads on 32-bit, it may be necessary to explicitly limit the stack size.
+
+	   udevd doesn't use crazy recursion or deep call-chains.
+	   But it does allocate quite a few buffers and temporary strings on the stack.
+	   We may also need extra space for exotic NSS modules (user/group lookup, e.g. over LDAP).
+	   Make a generous guess, double it, and double it again!
+
+	   This comes to just over 200Kb.  The default on i386 is 2Mb.
+	 */
+	stacksize = PTHREAD_STACK_MIN;
+	stacksize += UTIL_PATH_SIZE * 8;
+	stacksize += UTIL_LINE_SIZE * 8;
+	stacksize += UTIL_NAME_SIZE * 8;
+	stacksize += 4096 * 8;
+	stacksize *= 4;
+
+	/* Round up to a whole number of pages */
+	pagesize = sysconf(_SC_PAGESIZE);
+	stacksize = ((stacksize / pagesize) + 1) * pagesize;
+	pthread_attr_setstacksize(&thread_attr, stacksize);
+
 	/* OOM_DISABLE == -17 */
 	fd = open("/proc/self/oom_adj", O_RDWR);
 	if (fd < 0)
@@ -883,12 +869,14 @@ int main(int argc, char *argv[])
 	maxfd = udev_ctrl_get_fd(udev_ctrl);
 	maxfd = UDEV_MAX(maxfd, udev_monitor_get_fd(kernel_monitor));
 	maxfd = UDEV_MAX(maxfd, signal_pipe[READ_END]);
+	maxfd = UDEV_MAX(maxfd, event_done_pipe[READ_END]);
 	maxfd = UDEV_MAX(maxfd, inotify_fd);
 	while (!udev_exit) {
 		int fdcount;
 
 		FD_ZERO(&readfds);
 		FD_SET(signal_pipe[READ_END], &readfds);
+		FD_SET(event_done_pipe[READ_END], &readfds);
 		FD_SET(udev_ctrl_get_fd(udev_ctrl), &readfds);
 		FD_SET(udev_monitor_get_fd(kernel_monitor), &readfds);
 		if (inotify_fd >= 0)
@@ -927,6 +915,21 @@ int main(int argc, char *argv[])
 			read(signal_pipe[READ_END], &buf, sizeof(buf));
 		}
 
+		/* processed events */
+		if (FD_ISSET(event_done_pipe[READ_END], &readfds)) {
+			struct udev_event *buf[32];
+			ssize_t count;
+			unsigned i;
+
+			count = read(event_done_pipe[READ_END], &buf, sizeof(buf));
+			if (count < 0) {
+				err(udev, "read error on thread pipe: %m\n");
+			} else {
+				for (i = 0; i < count / sizeof(buf[0]); i++)
+					udev_done(buf[i]);
+			}
+		}
+
 		/* rules directory inotify watch */
 		if ((inotify_fd >= 0) && FD_ISSET(inotify_fd, &readfds)) {
 			int nbytes;
@@ -959,20 +962,28 @@ int main(int argc, char *argv[])
 			}
 		}
 
-		if (sigchilds_waiting) {
-			sigchilds_waiting = 0;
-			reap_sigchilds();
-		}
-
 		if (run_exec_q) {
 			run_exec_q = 0;
 			if (!stop_exec_q)
 				event_queue_manager(udev);
 		}
 	}
+
+	// todo unified queue
+	if (!udev_list_is_empty(&event_list)) {
+		struct udev_list_node *loop;
+
+		udev_list_node_foreach(loop, &event_list) {
+			struct udev_event *loop_event = node_to_event(loop);
+
+			if (loop_event->running)
+				event_thread_kill(loop_event);
+		}
+	}
 	cleanup_queue_dir(udev);
 	rc = 0;
 exit:
+	pthread_attr_destroy(&thread_attr);
 	udev_rules_unref(rules);
 	if (signal_pipe[READ_END] >= 0)
 		close(signal_pipe[READ_END]);

--------------050607090004090203040301--