From 47986995dec30eec382ebad67d0d59907fe6df23 Mon Sep 17 00:00:00 2001
From: Leonid Krivoshein <klark@altlinux.org>
Date: Mon, 25 Sep 2023 00:07:27 +0300
Subject: [PATCH 1/1] udev.c: redirect udev messages to /var/log/udevd.log

---
 udev.c | 55 +++++++++++++++++++++++++++++--------------------------
 1 file changed, 29 insertions(+), 26 deletions(-)

diff --git a/udev.c b/udev.c
index 0c211a9..e64dd0a 100644
--- a/udev.c
+++ b/udev.c
@@ -19,13 +19,14 @@
  *
  */
 
+#define _GNU_SOURCE
 #include <errno.h>
 #include <string.h>
 #include <stdlib.h>
 #include <stdio.h>
+#include <fcntl.h>
 #include <unistd.h>
 #include <dirent.h>
-#include <fcntl.h>
 #include <limits.h>
 #include <sys/stat.h>
 #include <sys/vfs.h>
@@ -49,17 +50,7 @@ extern char * const env[];
 static pid_t udevd_pid;
 
 
-static void spawn_wait(char * const command[], const char *message)
-{
-	int status = 0;
-
-	if (waitpid(spawn(command), &status, 0) < 0 || !(WIFEXITED(status))) {
-		warn(message);
-	}
-}
-
-
-static void spawn_silent(char * const command[])
+static pid_t spawn_silent(char * const command[], const char *log)
 {
 	int fd = 0;
 	pid_t pid = fork();
@@ -67,19 +58,31 @@ static void spawn_silent(char * const command[])
 	if (pid < 0)
 		fatal(command[0]);
 	else if (pid == 0) {
-		fd = open("/dev/null", O_WRONLY, 0666);
-		if (fd >= 0) {
-			dup2(fd, 1);
-			dup2(fd, 2);
-			close(fd);
-		}
+		if (log)
+			fd = creat(log, 0640);
+		else
+			fd = open(log = "/dev/null", O_WRONLY, 0644);
+		if (fd < 0)
+			fatal(log);
+		close(1);
+		close(2);
+		dup3(fd, 1, O_CLOEXEC);
+		dup3(1, 2, O_CLOEXEC);
+		close(fd);
 		execve(command[0], &command[1], env);
-		perror(command[0]);
-		exit(1);
+		fatal(command[0]);
 	}
 
-	if (waitpid(pid, &fd, 0) >= 0) {
-		fd = WIFEXITED(fd);
+	return pid;
+}
+
+
+static void spawn_wait(char * const command[], const char *message)
+{
+	int status = 0;
+
+	if (waitpid(spawn_silent(command, NULL), &status, 0) < 0 || !(WIFEXITED(status))) {
+		warn(message);
 	}
 }
 
@@ -105,16 +108,16 @@ void udev_start(void)
 
 	printf("Spawning udevd... ");
 
-	udevd_pid = spawn(udevd);
+	udevd_pid = spawn_silent(udevd, "/var/log/udevd.log");
 	spawn_wait(priority, "udev_priority");
 	spawn_wait(startup, "udev_startup");
-	spawn_silent(reload);
+	spawn_silent(reload, NULL);
 
 	if (mkdir_dev(".udev/queue") < 0)
 		fatal("cannot create /dev/.udev/queue");
 
-	spawn_silent(subsys);
-	spawn_silent(devices);
+	spawn_silent(subsys, NULL);
+	spawn_silent(devices, NULL);
 	udev_settle();
 
 	printf("done\n");
-- 
2.34.1