run(): add support for logging/redirect

This patch adds support for optional logging of output from all run()
commands.  For run_interactive() we've opted to log instead of just
redirect, meaning output on error is till on console but also in log.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

plugins/bootmisc.c

@@ -198,7 +198,7 @@ static void setup(void *arg)
 	mksubsys("/var/run/sudo", 0711, "root", "root");
 	mksubsys("/var/run/sudo/ts", 0700, "root", "root");
 	if (whichp("restorecon"))
-		run("restorecon /var/run/sudo /var/run/sudo/ts");
+		run("restorecon /var/run/sudo /var/run/sudo/ts", "restorecon");
 
 	umask(prev);
 }

plugins/procps.c

@@ -34,9 +34,7 @@
 
 static void setup(void *arg)
 {
-	size_t i;
 	glob_t gl;
-	char buf[160];
 
 	if (rescue) {
 		_d("Skipping %s plugin in rescue mode.", __FILE__);
@@ -51,9 +49,13 @@ static void setup(void *arg)
 	glob("/mnt/sysctl.d/*.conf",           GLOB_APPEND, NULL, &gl);
 	glob("/etc/sysctl.conf",               GLOB_APPEND, NULL, &gl);
 	if (gl.gl_pathc > 0) {
+		size_t i;
+
 		for (i = 0; i < gl.gl_pathc; i++) {
-			snprintf(buf, sizeof(buf), "/sbin/sysctl -e -p %s >/dev/null", gl.gl_pathv[i]);
-			run(buf);
+			char cmd[160];
+
+			snprintf(cmd, sizeof(cmd), "/sbin/sysctl -e -p %s >/dev/null", gl.gl_pathv[i]);
+			run(cmd, "sysctl");
 		}
 		globfree(&gl);
 	}

plugins/x11-common.c

@@ -58,7 +58,7 @@ static void setup(void *arg)
 	if ((fd = open("/var/run/console/console.lock", O_CREAT|O_WRONLY|O_TRUNC, 0644)) >= 0) {
 		write(fd, username, strlen(username));
 		close(fd);
-		run("pam_console_apply");
+		run("pam_console_apply", "pam-console");
 	}
 #endif
 
@@ -66,7 +66,7 @@ static void setup(void *arg)
 	makedir("/tmp/.ICE-unix", 01777);
 
 	if (whichp("restorecon"))
-		run("restorecon /tmp/.ICE-unix /tmp/.X11-unix");
+		run("restorecon /tmp/.ICE-unix /tmp/.X11-unix", "restorecon");
 
 	umask(prev);
 }

src/exec.c

@@ -28,6 +28,7 @@
 #include <dirent.h>
 #include <err.h>
 #include <stdarg.h>
+#include <sysexits.h>
 #include <sys/ioctl.h>
 #include <sys/prctl.h>
 #include <sys/wait.h>
@@ -70,74 +71,110 @@ int complete(char *cmd, int pid)
 	return status;
 }
 
-int run(char *cmd)
+static int do_redirect(void)
+{
+	FILE *fp;
+
+	fp = fopen("/dev/null", "w");
+	if (fp) {
+		int fd = fileno(fp);
+
+		dup2(fd, STDIN_FILENO);
+		dup2(fd, STDOUT_FILENO);
+		dup2(fd, STDERR_FILENO);
+
+		return fclose(fp);
+	}
+
+	return -1;
+}
+
+/*
+ * Run 'cmd' and wait for completion.  If 'log' is not NULL any output
+ * from the command is logged with the given string as prefix, use "" to
+ * skip.  If 'log' is NULL all output is redirected to /dev/null, which
+ * is what this function originally did.
+ */
+int run(char *cmd, char *log)
 {
 	int status, result, i = 0;
-	char *args[NUM_ARGS + 1], *arg, *backup;
+	char *args[NUM_ARGS + 1], *arg;
+	char *backup = NULL;
 	pid_t pid;
 
-	/* We must create a copy that is possible to modify. */
-	backup = arg = strdup(cmd);
-	if (!arg)
-		return 1; /* Failed allocating a string to be modified. */
+	if (!log) {
+		/* We must create a copy that is possible to modify. */
+		backup = arg = strdup(cmd);
+		if (!arg)
+			return 1;
 
-	/* Split command line into tokens of an argv[] array. */
-	args[i++] = strsep(&arg, "\t ");
-	while (arg && i < NUM_ARGS) {
-		/* Handle run("su -c \"dbus-daemon --system\" messagebus");
-		 *   => "su", "-c", "\"dbus-daemon --system\"", "messagebus" */
-		if (*arg == '\'' || *arg == '"') {
-			char *p, delim[2] = " ";
+		/* Split command line into tokens of an argv[] array. */
+		args[i++] = strsep(&arg, "\t ");
+		while (arg && i < NUM_ARGS) {
+			/* Handle run("su -c \"dbus-daemon --system\" messagebus");
+			 *   => "su", "-c", "\"dbus-daemon --system\"", "messagebus" */
+			if (*arg == '\'' || *arg == '"') {
+				char *p, delim[2] = " ";
 
-			delim[0]  = arg[0];
-			args[i++] = arg++;
-			strsep(&arg, delim);
-			 p     = arg - 1;
-			*p     = *delim;
-			*arg++ = 0;
-		} else {
-			args[i++] = strsep(&arg, "\t ");
+				delim[0]  = arg[0];
+				args[i++] = arg++;
+				strsep(&arg, delim);
+				 p     = arg - 1;
+				*p     = *delim;
+				*arg++ = 0;
+			} else {
+				args[i++] = strsep(&arg, "\t ");
+			}
 		}
-	}
-	args[i] = NULL;
+		args[i] = NULL;
 
-	if (i == NUM_ARGS && arg) {
-		_e("Command too long: %s", cmd);
-		free(backup);
-		errno = EOVERFLOW;
-		return 1;
+		if (i == NUM_ARGS && arg) {
+			_e("Command too long: %s", cmd);
+			free(backup);
+			errno = EOVERFLOW;
+			return 1;
+		}
 	}
 
 	pid = fork();
 	if (0 == pid) {
-		FILE *fp;
+		int rc = EX_OSERR;
 
 		setsid();
+		sig_unblock();
+		if (!log) {
+			do_redirect();
+			execvp(args[0], args);
+		} else {
+			char *pfx = *log ? ": " : "";
+			FILE *pp;
 
-		/* Always redirect stdio for run() */
-		fp = fopen("/dev/null", "w");
-		if (fp) {
-			int fd = fileno(fp);
+			pp = popen(cmd, "r");
+			if (pp) {
+				char buf[256];
 
-			dup2(fd, STDIN_FILENO);
-			dup2(fd, STDOUT_FILENO);
-			dup2(fd, STDERR_FILENO);
+				while (fgets(buf, sizeof(buf), pp)) {
+					chomp(buf);
+					logit(LOG_NOTICE, "%s%s%s", log, pfx, buf);
+				}
+
+				rc = pclose(pp);
+			}
 		}
 
-		sig_unblock();
-		execvp(args[0], args);
-
-		_exit(1); /* Only if execv() fails. */
+		_exit(rc);
 	} else if (-1 == pid) {
 		_pe("%s", args[0]);
-		free(backup);
+		if (backup)
+			free(backup);
 
 		return -1;
 	}
 
 	status = complete(args[0], pid);
 	if (-1 == status) {
-		free(backup);
+		if (backup)
+			free(backup);
 		return 1;
 	}
 
@@ -152,7 +189,8 @@ int run(char *cmd)
 				     * change their return code accordingly. --Jocke */
 	}
 
-	free(backup);
+	if (backup)
+		free(backup);
 
 	return result;
 }
@@ -186,7 +224,7 @@ int run_interactive(char *cmd, char *fmt, ...)
 	}
 
 	/* Run cmd ... */
-	status = run(cmd);
+	status = run(cmd, "");
 
 	/* Restore stderr/stdout */
 	if (fp && !debug) {

src/finit.c

@@ -333,7 +333,7 @@ static void fs_mount_all(void)
 	_d("Calling extra mount hook, after mount -a ...");
 	plugin_run_hooks(HOOK_MOUNT_POST);
 
-	run("swapon -ea");
+	run("swapon -ea", "swapon");
 
 	_d("Finalize, ensure common file systems are available ...");
 	fs_finalize();

src/helpers.h

@@ -96,7 +96,7 @@ void    networking      (int updown);
 int     in_container    (void);
 
 int     complete        (char *cmd, int pid);
-int     run             (char *cmd);
+int     run             (char *cmd, char *log);
 int     run_interactive (char *cmd, char *fmt, ...);
 int     exec_runtask    (char *cmd, char *args[]);
 pid_t   run_getty       (char *tty, char *cmd, char *args[], int noclear, int nowait, struct rlimit rlimit[]);

src/sig.c

@@ -313,16 +313,16 @@ void do_shutdown(shutop_t op)
 
 	/* Unmount any tmpfs before unmounting swap ... */
 	unmount_tmpfs();
-	run("swapoff -e -a");
+	run("swapoff -e -a", "swapoff");
 
 	/* ... unmount remaining regular file systems. */
 	unmount_regular();
 
 	/* We sit on / so we must remount it ro, try all the things! */
 	sync();
-	run("mount -n -o remount,ro -t dummytype dummydev /");
-	run("mount -n -o remount,ro dummydev /");
-	run("mount -n -o remount,ro /");
+	run("mount -n -o remount,ro -t dummytype dummydev /", "mount");
+	run("mount -n -o remount,ro dummydev /", "mount");
+	run("mount -n -o remount,ro /", "mount");
 
 	/* Call mdadm to mark any RAID array(s) as clean before halting. */
 	mdadm_wait();