cmd/Makemodule.am

@@ -3,6 +3,12 @@ shutdown_CPPFLAGS = $(AM_CPPFLAGS)
 shutdown_CFLAGS = $(AM_CFLAGS)
 shutdown_LDFLAGS = $(AM_LDFLAGS)
 
+runsvc_SOURCES = cmd/runsvc/runsvc.c cmd/runsvc/env.c cmd/runsvc/runsvc.h
+runsvc_CPPFLAGS = $(AM_CPPFLAGS)
+runsvc_CFLAGS = $(AM_CFLAGS)
+runsvc_LDFLAGS = $(AM_LDFLAGS)
+runsvc_LDADD = libinit.a libcfg.a libutil.a
+
 killall5_SOURCES = cmd/killall5.c
 killall5_CPPFLAGS = $(AM_CPPFLAGS)
 killall5_CFLAGS = $(AM_CFLAGS)
@@ -24,11 +30,11 @@ service_SOURCES += $(SRVHEADERS)
 service_CPPFLAGS = $(AM_CPPFLAGS)
 service_CFLAGS = $(AM_CFLAGS)
 service_LDFLAGS = $(AM_LDFLAGS)
-service_LDADD = libinit.a libcfg.a
+service_LDADD = libinit.a libcfg.a libutil.a
 
 dist_man8_MANS += cmd/shutdown.8 cmd/service/service.8
 
 EXTRA_DIST += $(SRVHEADERS)
 
 sbin_PROGRAMS += service shutdown
-helper_PROGRAMS += killall5 waitfile
+helper_PROGRAMS += killall5 runsvc waitfile

cmd/killall5.c

@@ -9,7 +9,9 @@
 #include <ctype.h>
 #include <errno.h>
 
-static __attribute__((noreturn)) void usage_and_exit(void)
+#include "util.h"
+
+static NORETURN void usage_and_exit(void)
 {
 	fputs("Usage: killall5 SIGNAL\n", stderr);
 	exit(EXIT_FAILURE);

cmd/runsvc/env.c

@@ -0,0 +1,109 @@
+/* SPDX-License-Identifier: ISC */
+#include "runsvc.h"
+
+struct entry {
+	struct entry *next;
+	char data[];
+};
+
+extern char **environ;
+
+static void free_list(struct entry *list)
+{
+	struct entry *e;
+
+	while (list != NULL) {
+		e = list;
+		list = list->next;
+		free(e);
+	}
+}
+
+static struct entry *parse_list(rdline_t *rd)
+{
+	struct entry *e, *list = NULL;
+	char *ptr;
+
+	while (rdline(rd) == 0) {
+		ptr = rd->line;
+
+		while (*ptr != '\0' && *ptr != ' ' && *ptr != '=')
+			++ptr;
+
+		if (*ptr == ' ')
+			memmove(ptr, ptr + 1, strlen(ptr + 1) + 1);
+
+		if (*(ptr++) != '=') {
+			fprintf(stderr, "%s: %zu: line is not of the shape "
+					"'key = value', skipping\n",
+				rd->filename, rd->lineno);
+			continue;
+		}
+
+		if (*ptr == ' ')
+			memmove(ptr, ptr + 1, strlen(ptr + 1) + 1);
+
+		if (unescape(ptr)) {
+			fprintf(stderr, "%s: %zu: malformed string constant, "
+					"skipping\n",
+				rd->filename, rd->lineno);
+			continue;
+		}
+
+		e = calloc(1, sizeof(*e) + strlen(rd->line) + 1);
+		if (e == NULL)
+			goto fail_oom;
+
+		strcpy(e->data, rd->line);
+		e->next = list;
+		list = e;
+	}
+
+	return list;
+fail_oom:
+	fputs("out of memory\n", stderr);
+	free_list(list);
+	return NULL;
+}
+
+static struct entry *list_from_file(void)
+{
+	struct entry *list;
+	rdline_t rd;
+
+	if (rdline_init(&rd, AT_FDCWD, ENVFILE, 0, NULL))
+		return NULL;
+
+	list = parse_list(&rd);
+	rdline_cleanup(&rd);
+	return list;
+}
+
+int initenv(void)
+{
+	struct entry *list, *e;
+	int i, count;
+	char **envp;
+
+	list = list_from_file();
+	if (list == NULL)
+		return -1;
+
+	for (count = 0, e = list; e != NULL; e = e->next)
+		++count;
+
+	envp = malloc((count + 1) * sizeof(char *));
+	if (envp == NULL) {
+		fputs("out of memory\n", stderr);
+		free_list(list);
+		return -1;
+	}
+
+	for (i = 0, e = list; e != NULL; e = e->next)
+		envp[i] = e->data;
+
+	envp[i] = NULL;
+
+	environ = envp;
+	return 0;
+}

cmd/runsvc/runsvc.c

@@ -0,0 +1,72 @@
+/* SPDX-License-Identifier: ISC */
+#include "runsvc.h"
+
+static int run_sequentially(exec_t *list)
+{
+	pid_t ret, pid;
+	int status;
+
+	for (; list != NULL; list = list->next) {
+		if (list->next == NULL)
+			argv_exec(list);
+
+		pid = fork();
+
+		if (pid == 0)
+			argv_exec(list);
+
+		if (pid == -1) {
+			perror("fork");
+			return EXIT_FAILURE;
+		}
+
+		do {
+			ret = waitpid(pid, &status, 0);
+		} while (ret != pid);
+
+		if (!WIFEXITED(status))
+			return EXIT_FAILURE;
+
+		if (WEXITSTATUS(status) != EXIT_SUCCESS)
+			return WEXITSTATUS(status);
+	}
+
+	return EXIT_SUCCESS;
+}
+
+/*****************************************************************************/
+
+int main(int argc, char **argv)
+{
+	service_t *svc = NULL;
+	int dirfd;
+
+	if (argc != 3) {
+		fputs("usage: runsvc <directory> <filename>\n", stderr);
+		return EXIT_FAILURE;
+	}
+
+	if (getppid() != 1) {
+		fputs("must be run by init!\n", stderr);
+		return EXIT_FAILURE;
+	}
+
+	dirfd = open(argv[1], O_RDONLY | O_DIRECTORY);
+	if (dirfd < 0) {
+		perror(argv[1]);
+		return EXIT_FAILURE;
+	}
+
+	svc = rdsvc(dirfd, argv[2], RDSVC_NO_FNAME | RDSVC_NO_DEPS);
+	close(dirfd);
+	if (svc == NULL)
+		return EXIT_FAILURE;
+
+	if (initenv())
+		return EXIT_FAILURE;
+
+	if (setup_tty(svc->ctty, (svc->flags & SVC_FLAG_TRUNCATE_OUT) != 0))
+		return EXIT_FAILURE;
+
+	return run_sequentially(svc->exec);
+}

cmd/runsvc/runsvc.h

@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: ISC */
+#ifndef RUNSVC_H
+#define RUNSVC_H
+
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <fcntl.h>
+
+#include "service.h"
+#include "libcfg.h"
+#include "util.h"
+
+#define ENVFILE ETCPATH "/initd.env"
+
+int initenv(void);
+
+#endif /* RUNSVC_H */

cmd/service/dumpscript.c

@@ -93,7 +93,7 @@ static int cmd_dumpscript(int argc, char **argv)
 		strcat(filename, argv[i]);
 	}
 
-	svc = loadsvc(SVCDIR, filename);
+	svc = loadsvc(SVCDIR, filename, 0);
 
 	if (svc == NULL) {
 		fprintf(stderr, "Could not load service '%s'\n", filename);

cmd/service/list.c

@@ -24,7 +24,7 @@ static int cmd_list(int argc, char **argv)
 	if (check_arguments(argv[0], argc, 1, 2))
 		return EXIT_FAILURE;
 
-	if (svcscan(SVCDIR, &list)) {
+	if (svcscan(SVCDIR, &list, 0)) {
 		fprintf(stderr, "Error while reading services from %s\n",
 			SVCDIR);
 		ret = EXIT_FAILURE;

cmd/service/loadsvc.c

@@ -5,7 +5,7 @@
 #include <fcntl.h>
 #include <stdio.h>
 
-service_t *loadsvc(const char *directory, const char *filename)
+service_t *loadsvc(const char *directory, const char *filename, int flags)
 {
 	service_t *svc;
 	int dirfd;
@@ -17,7 +17,7 @@ service_t *loadsvc(const char *directory, const char *filename)
 		return NULL;
 	}
 
-	svc = rdsvc(dirfd, filename);
+	svc = rdsvc(dirfd, filename, flags);
 	close(dirfd);
 	return svc;
 }

cmd/service/servicecmd.c

@@ -5,6 +5,7 @@
 #include "servicecmd.h"
 #include "service.h"
 #include "config.h"
+#include "util.h"
 
 
 command_t *commands;

cmd/service/servicecmd.h

@@ -2,14 +2,13 @@
 #ifndef SERVICECMD_H
 #define SERVICECMD_H
 
-#include <stdbool.h>
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>
 #include <ctype.h>
 
 #include "service.h"
-#include "config.h"
+#include "util.h"
 
 /*
 	Describes a command that can be launched by passing its name as
@@ -40,13 +39,13 @@ typedef struct command_t {
 /* Global list of available commands */
 extern command_t *commands;
 
-service_t *loadsvc(const char *directory, const char *filename);
+service_t *loadsvc(const char *directory, const char *filename, int flags);
 
 /*
 	Implemented in servicecmd.c. Prints program usage message and
 	terminates with the given exit status.
 */
-void usage(int status) __attribute__((noreturn));
+void usage(int status) NORETURN;
 
 /*
 	Write a message to stderr that advises the user how to consult the

cmd/service/status.c

@@ -128,7 +128,9 @@ static int cmd_status(int argc, char **argv)
 			printf("\tTemplate name: %s\n", resp.service_name);
 			printf("\tExit status: %d\n", resp.exit_status);
 
-			svc = loadsvc(SVCDIR, resp.filename);
+			svc = loadsvc(SVCDIR, resp.filename,
+				      RDSVC_NO_EXEC | RDSVC_NO_DEPS |
+				      RDSVC_NO_CTTY | RDSVC_NO_FNAME);
 
 			if (svc == NULL) {
 				fputs("\tError loading service file\n", stdout);

cmd/shutdown.c

@@ -10,6 +10,8 @@
 #include <sys/reboot.h>
 #include <linux/reboot.h>
 
+#include "util.h"
+
 #define FL_FORCE 0x01
 #define FL_NOSYNC 0x02
 
@@ -27,7 +29,7 @@ static const char *shortopt = "hprfn";
 static const char *defact_str = "power-off";
 static int defact = RB_POWER_OFF;
 
-static __attribute__((noreturn)) void usage(const char *progname, int status)
+static NORETURN void usage(const char *progname, int status)
 {
 	fprintf(status == EXIT_SUCCESS ? stdout : stderr,
 "%s [OPTIONS...]\n\n"

initd/Makemodule.am

@@ -1,8 +1,8 @@
-init_SOURCES = initd/main.c initd/init.h initd/runsvc.c
+init_SOURCES = initd/main.c initd/init.h initd/signal_linux.c initd/runsvc.c
 init_SOURCES += initd/status.c initd/supervisor.c initd/initsock.c
 init_CPPFLAGS = $(AM_CPPFLAGS)
 init_CFLAGS = $(AM_CFLAGS)
 init_LDFLAGS = $(AM_LDFLAGS)
-init_LDADD = libinit.a libcfg.a
+init_LDADD = libinit.a libcfg.a libutil.a
 
 sbin_PROGRAMS += init

initd/init.h

@@ -17,15 +17,13 @@
 #include <linux/reboot.h>
 #include <sys/signalfd.h>
 #include <sys/reboot.h>
-#include <stdbool.h>
 #include <signal.h>
 
 #include "initsock.h"
 #include "service.h"
-#include "config.h"
+#include "util.h"
 
-#define ENVFILE ETCPATH "/initd.env"
-#define PROCFDDIR "/proc/self/fd"
+#define RUNSVCBIN SCRIPTDIR "/runsvc"
 
 enum {
 	STATUS_OK = 0,
@@ -79,6 +77,29 @@ void supervisor_start(int id);
 
 void supervisor_stop(int id);
 
+/********** signal_<platform>.c **********/
+
+/*
+	Setup signal handling. Returns -1 on error, a file descriptor on
+	success.
+
+	The returned file descriptor can be polled and becomes readable
+	when a signal arrives. Reading from it returns a signalfd_siginfo
+	structure.
+
+	The returned file descriptor has the close on exec flag set.
+
+	The kernel is also told to send us SIGINT signals if a user presses
+	the local equivalent of CTRL+ALT+DEL.
+*/
+int sigsetup(void);
+
+/*
+	Undo everything that sigsetup() changed about signal handling and
+	restore the default.
+*/
+void sigreset(void);
+
 /********** initsock.c **********/
 
 int init_socket_create(void);

initd/main.c

@@ -96,29 +96,6 @@ void target_completed(int target)
 	}
 }
 
-static int sigsetup(void)
-{
-	sigset_t mask;
-	int sfd;
-
-	sigfillset(&mask);
-	if (sigprocmask(SIG_SETMASK, &mask, NULL) == -1) {
-		perror("sigprocmask");
-		return -1;
-	}
-
-	sfd = signalfd(-1, &mask, SFD_CLOEXEC);
-	if (sfd == -1) {
-		perror("signalfd");
-		return -1;
-	}
-
-	if (reboot(LINUX_REBOOT_CMD_CAD_OFF))
-		perror("cannot disable CTRL+ALT+DEL");
-
-	return sfd;
-}
-
 int main(void)
 {
 	int i, ret, count;

initd/runsvc.c

@@ -3,175 +3,32 @@
 #include <sys/wait.h>
 #include <unistd.h>
 #include <stdlib.h>
-#include <dirent.h>
 #include <stdio.h>
-#include <fcntl.h>
-#include <errno.h>
-#include <ctype.h>
 
 #include "init.h"
 
-static int setup_env(void)
-{
-	int status = -1;
-	ssize_t ret;
-	FILE *fp;
-
-	clearenv();
-
-	fp = fopen(ENVFILE, "r");
-	if (fp == NULL) {
-		perror(ENVFILE);
-		return -1;
-	}
-
-	do {
-		char *line = NULL;
-		size_t n = 0;
-
-		errno = 0;
-		ret = getline(&line, &n, fp);
-
-		if (ret < 0) {
-			if (errno == 0) {
-				status = 0;
-			} else {
-				perror(ENVFILE);
-			}
-		} else if (ret > 0 && putenv(line) != 0) {
-			perror("putenv");
-			ret = -1;
-		}
-
-		free(line);
-	} while (ret >= 0);
-
-	fclose(fp);
-	return status;
-}
-
-static int close_all_files(void)
-{
-	struct dirent *ent;
-	DIR *dir;
-	int fd;
-
-	dir = opendir(PROCFDDIR);
-	if (dir == NULL) {
-		perror(PROCFDDIR);
-		return -1;
-	}
-
-	while ((ent = readdir(dir)) != NULL) {
-		if (!isdigit(ent->d_name[0]))
-			continue;
-
-		fd = atoi(ent->d_name);
-		close(fd);
-	}
-
-	closedir(dir);
-	return 0;
-}
-
-static int setup_tty(const char *tty, bool truncate)
-{
-	int fd;
-
-	if (tty == NULL)
-		return 0;
-
-	fd = open(tty, O_RDWR);
-	if (fd < 0) {
-		perror(tty);
-		return -1;
-	}
-
-	if (truncate)
-		ftruncate(fd, 0);
-
-	setsid();
-
-	dup2(fd, STDIN_FILENO);
-	dup2(fd, STDOUT_FILENO);
-	dup2(fd, STDERR_FILENO);
-	close(fd);
-	return 0;
-}
-
-static __attribute__((noreturn)) void argv_exec(exec_t *e)
-{
-	char **argv = alloca(sizeof(char *) * (e->argc + 1)), *ptr;
-	int i;
-
-	for (ptr = e->args, i = 0; i < e->argc; ++i, ptr += strlen(ptr) + 1)
-		argv[i] = ptr;
-
-	argv[i] = NULL;
-	execvp(argv[0], argv);
-	perror(argv[0]);
-	exit(EXIT_FAILURE);
-}
-
-static int run_sequentially(exec_t *list)
-{
-	pid_t ret, pid;
-	int status;
-
-	for (; list != NULL; list = list->next) {
-		if (list->next == NULL)
-			argv_exec(list);
-
-		pid = fork();
-
-		if (pid == 0)
-			argv_exec(list);
-
-		if (pid == -1) {
-			perror("fork");
-			return EXIT_FAILURE;
-		}
-
-		do {
-			ret = waitpid(pid, &status, 0);
-		} while (ret != pid);
-
-		if (!WIFEXITED(status))
-			return EXIT_FAILURE;
-
-		if (WEXITSTATUS(status) != EXIT_SUCCESS)
-			return WEXITSTATUS(status);
-	}
-
-	return EXIT_SUCCESS;
-}
-
 pid_t runsvc(service_t *svc)
 {
-	sigset_t mask;
+	char *argv[4], *envp[1];
 	pid_t pid;
 
+	argv[0] = (char *)RUNSVCBIN;
+	argv[1] = (char *)SVCDIR;
+	argv[2] = svc->fname;
+	argv[3] = NULL;
+
+	envp[0] = NULL;
+
 	pid = fork();
 
 	if (pid == -1)
 		perror("fork");
 
 	if (pid == 0) {
-		sigemptyset(&mask);
-		sigprocmask(SIG_SETMASK, &mask, NULL);
-
-		if (setup_env())
-			exit(EXIT_FAILURE);
-
-		if (close_all_files())
-			exit(EXIT_FAILURE);
-
-		if (setup_tty(svc->ctty,
-			      (svc->flags & SVC_FLAG_TRUNCATE_OUT) != 0)) {
-			exit(EXIT_FAILURE);
-		}
-
-		exit(run_sequentially(svc->exec));
+		sigreset();
+		execve(argv[0], argv, envp);
+		perror(argv[0]);
+		exit(EXIT_FAILURE);
 	}
 
 	return pid;

initd/signal_linux.c

@@ -0,0 +1,42 @@
+/* SPDX-License-Identifier: ISC */
+#include <stdio.h>
+
+#include "init.h"
+
+int sigsetup(void)
+{
+	sigset_t mask;
+	int sfd;
+
+	sigfillset(&mask);
+	if (sigprocmask(SIG_SETMASK, &mask, NULL) == -1) {
+		perror("sigprocmask");
+		return -1;
+	}
+
+	sigemptyset(&mask);
+	sigaddset(&mask, SIGCHLD);
+	sigaddset(&mask, SIGINT);
+	sigaddset(&mask, SIGTERM);
+	sigaddset(&mask, SIGUSR1);
+	sigaddset(&mask, SIGHUP);
+
+	sfd = signalfd(-1, &mask, SFD_CLOEXEC);
+	if (sfd == -1) {
+		perror("signalfd");
+		return -1;
+	}
+
+	if (reboot(LINUX_REBOOT_CMD_CAD_OFF))
+		perror("cannot disable CTRL+ALT+DEL");
+
+	return sfd;
+}
+
+void sigreset(void)
+{
+	sigset_t mask;
+
+	sigemptyset(&mask);
+	sigprocmask(SIG_SETMASK, &mask, NULL);
+}

initd/supervisor.c

@@ -175,7 +175,7 @@ void supervisor_init(void)
 {
 	int status = STATUS_OK;
 
-	if (svcscan(SVCDIR, &cfg))
+	if (svcscan(SVCDIR, &cfg, RDSVC_NO_EXEC | RDSVC_NO_CTTY))
 		status = STATUS_FAIL;
 
 	target = TGT_BOOT;
@@ -191,7 +191,7 @@ void supervisor_reload_config(void)
 	service_t *svc;
 	int i;
 
-	if (svcscan(SVCDIR, &newcfg))
+	if (svcscan(SVCDIR, &newcfg, RDSVC_NO_EXEC | RDSVC_NO_CTTY))
 		return;
 
 	for (i = 0; i < TGT_MAX; ++i) {
@@ -317,7 +317,7 @@ static service_t *remove_by_id(service_t **list, int id)
 		if (prev == NULL) {
 			*list = svc->next;
 		} else {
-			prev->next = svc->next;
+			prev = svc->next;
 		}
 	}
 

lib/Makemodule.am

@@ -7,9 +7,13 @@ libinit_a_SOURCES += lib/init/init_socket_recv_status.c
 libinit_a_CPPFLAGS = $(AM_CPPFLAGS)
 libinit_a_CFLAGS = $(AM_CFLAGS)
 
+libutil_a_SOURCES = lib/util/argv_exec.c lib/include/util.h
+libutil_a_CPPFLAGS = $(AM_CPPFLAGS)
+libutil_a_CFLAGS = $(AM_CFLAGS)
+
 libcfg_a_SOURCES = lib/libcfg/rdline.c lib/libcfg/unescape.c lib/libcfg/rdcfg.c
 libcfg_a_SOURCES += lib/libcfg/pack_argv.c lib/include/libcfg.h
 libcfg_a_CPPFLAGS = $(AM_CPPFLAGS)
 libcfg_a_CFLAGS = $(AM_CFLAGS)
 
-noinst_LIBRARIES += libinit.a libcfg.a
+noinst_LIBRARIES += libinit.a libcfg.a libutil.a

lib/include/libcfg.h

@@ -27,7 +27,7 @@ typedef struct {
 	 */
 	unsigned int allow_block : 1;
 
-	int (*handle)(void *obj, char *arg, rdline_t *rd);
+	int (*handle)(void *obj, char *arg, rdline_t *rd, int flags);
 } cfg_param_t;
 
 /*
@@ -92,10 +92,11 @@ int pack_argv(char *str);
 
 /*
 	Parse a configuration file containing '<keyword> [arguments...]' lines.
-	The cfgobj is passed to the callback in the params array.
+	The cfgobj and flags are passed to the callback in the params array.
 
 	Returns zero on success.
  */
-int rdcfg(void *cfgobj, rdline_t *rd, const cfg_param_t *params, size_t count);
+int rdcfg(void *cfgobj, rdline_t *rd, const cfg_param_t *params, size_t count,
+	  int flags);
 
 #endif /* LIBCONFIG_H */

lib/include/service.h

@@ -4,11 +4,7 @@
 
 #include <sys/types.h>
 
-typedef struct exec_t {
-	struct exec_t *next;
-	int argc;		/* number of elements in argument vector */
-	char args[];		/* argument vectot string blob */
-} exec_t;
+#include "util.h"
 
 enum {
 	/*
@@ -35,6 +31,13 @@ enum {
 	TGT_MAX
 };
 
+enum {
+	RDSVC_NO_FNAME = 0x01,	/* do not store a copy of the filename */
+	RDSVC_NO_EXEC = 0x02,	/* do not store executable script */
+	RDSVC_NO_CTTY = 0x04,	/* do not store the controlling tty */
+	RDSVC_NO_DEPS = 0x08,	/* do not store dependencies */
+};
+
 enum {
 	/* truncate stdout */
 	SVC_FLAG_TRUNCATE_OUT = 0x01,
@@ -79,7 +82,7 @@ typedef struct {
 /*
 	Read a service from a file.
 */
-service_t *rdsvc(int dirfd, const char *filename);
+service_t *rdsvc(int dirfd, const char *filename, int flags);
 
 void delsvc(service_t *svc);
 
@@ -90,7 +93,7 @@ void delsvc(service_t *svc);
 	Returns 0 on success, -1 on failure. The function takes care of
 	printing error messages on failure.
 */
-int svcscan(const char *directory, service_list_t *list);
+int svcscan(const char *directory, service_list_t *list, int flags);
 
 void del_svc_list(service_list_t *list);
 

lib/include/util.h

@@ -0,0 +1,39 @@
+/* SPDX-License-Identifier: ISC */
+#ifndef UTIL_H
+#define UTIL_H
+
+#include <sys/types.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdio.h>
+
+#include "config.h"
+
+#ifdef __GNUC__
+	#define NORETURN __attribute__((noreturn))
+#endif
+
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
+
+typedef struct exec_t {
+	struct exec_t *next;
+	int argc;		/* number of elements in argument vector */
+	char args[];		/* argument vectot string blob */
+} exec_t;
+
+enum {
+	/* only allow root to connect */
+	SOCK_FLAG_ROOT_ONLY = 0x01,
+
+	/* allow everyone to connect */
+	SOCK_FLAG_EVERYONE = 0x02,
+
+	/* create a datagram socket, otherwise use a stream socket */
+	SOCK_FLAG_DGRAM = 0x04,
+};
+
+int setup_tty(const char *tty, bool truncate);
+
+NORETURN void argv_exec(exec_t *e);
+
+#endif /* UTIL_H */

lib/init/rdsvc.c

@@ -11,6 +11,7 @@
 
 #include "service.h"
 #include "libcfg.h"
+#include "util.h"
 
 static int try_unescape(char *arg, rdline_t *rd)
 {
@@ -43,9 +44,10 @@ static int try_pack_argv(char *str, rdline_t *rd)
 	return count;
 }
 
-static int svc_desc(void *user, char *arg, rdline_t *rd)
+static int svc_desc(void *user, char *arg, rdline_t *rd, int flags)
 {
 	service_t *svc = user;
+	(void)flags;
 
 	if (try_unescape(arg, rd))
 		return -1;
@@ -53,10 +55,13 @@ static int svc_desc(void *user, char *arg, rdline_t *rd)
 	return svc->desc == NULL ? -1 : 0;
 }
 
-static int svc_tty(void *user, char *arg, rdline_t *rd)
+static int svc_tty(void *user, char *arg, rdline_t *rd, int flags)
 {
 	service_t *svc = user;
 
+	if (flags & RDSVC_NO_CTTY)
+		return 0;
+
 	if (strncmp(arg, "truncate", 8) == 0 && isspace(arg[8])) {
 		svc->flags |= SVC_FLAG_TRUNCATE_OUT;
 		arg += 8;
@@ -71,13 +76,16 @@ static int svc_tty(void *user, char *arg, rdline_t *rd)
 	return svc->ctty == NULL ? -1 : 0;
 }
 
-static int svc_exec(void *user, char *arg, rdline_t *rd)
+static int svc_exec(void *user, char *arg, rdline_t *rd, int flags)
 {
 	service_t *svc = user;
 	exec_t *e, *end;
 
 	svc->flags |= SVC_FLAG_HAS_EXEC;
 
+	if (flags & RDSVC_NO_EXEC)
+		return 0;
+
 	e = calloc(1, sizeof(*e) + strlen(arg) + 1);
 	if (e == NULL) {
 		fprintf(stderr, "%s: %zu: out of memory\n",
@@ -101,10 +109,13 @@ static int svc_exec(void *user, char *arg, rdline_t *rd)
 	return 0;
 }
 
-static int svc_before(void *user, char *arg, rdline_t *rd)
+static int svc_before(void *user, char *arg, rdline_t *rd, int flags)
 {
 	service_t *svc = user;
 
+	if (flags & RDSVC_NO_DEPS)
+		return 0;
+
 	if (svc->before != NULL) {
 		fprintf(stderr, "%s: %zu: 'before' dependencies respecified\n",
 			rd->filename, rd->lineno);
@@ -119,10 +130,13 @@ static int svc_before(void *user, char *arg, rdline_t *rd)
 	return (svc->num_before < 0) ? -1 : 0;
 }
 
-static int svc_after(void *user, char *arg, rdline_t *rd)
+static int svc_after(void *user, char *arg, rdline_t *rd, int flags)
 {
 	service_t *svc = user;
 
+	if (flags & RDSVC_NO_DEPS)
+		return 0;
+
 	if (svc->after != NULL) {
 		fprintf(stderr, "%s: %zu: 'after' dependencies respecified\n",
 			rd->filename, rd->lineno);
@@ -137,10 +151,11 @@ static int svc_after(void *user, char *arg, rdline_t *rd)
 	return (svc->num_after < 0) ? -1 : 0;
 }
 
-static int svc_type(void *user, char *arg, rdline_t *rd)
+static int svc_type(void *user, char *arg, rdline_t *rd, int flags)
 {
 	service_t *svc = user;
 	int count = try_pack_argv(arg, rd);
+	(void)flags;
 
 	if (count < 1)
 		return -1;
@@ -184,10 +199,11 @@ fail_limit:
 	return -1;
 }
 
-static int svc_target(void *user, char *arg, rdline_t *rd)
+static int svc_target(void *user, char *arg, rdline_t *rd, int flags)
 {
 	service_t *svc = user;
 	int target;
+	(void)flags;
 
 	if (try_unescape(arg, rd))
 		return -1;
@@ -214,7 +230,7 @@ static const cfg_param_t svc_params[] = {
 	{ "after", 0, svc_after },
 };
 
-service_t *rdsvc(int dirfd, const char *filename)
+service_t *rdsvc(int dirfd, const char *filename, int flags)
 {
 	const char *arg, *args[1];
 	service_t *svc = NULL;
@@ -238,17 +254,17 @@ service_t *rdsvc(int dirfd, const char *filename)
 	if (svc == NULL)
 		goto fail_oom;
 
-	svc->fname = strdup(filename);
-	if (svc->fname == NULL)
-		goto fail_oom;
+	if (!(flags & RDSVC_NO_FNAME)) {
+		svc->fname = strdup(filename);
+		if (svc->fname == NULL)
+			goto fail_oom;
+	}
 
 	memcpy(svc->name, filename, nlen);
 	svc->id = -1;
 
-	if (rdcfg(svc, &rd, svc_params,
-		  sizeof(svc_params) / sizeof(svc_params[0]))) {
+	if (rdcfg(svc, &rd, svc_params, ARRAY_SIZE(svc_params), flags))
 		goto fail;
-	}
 
 out:
 	rdline_cleanup(&rd);

lib/init/svcmap.c

@@ -23,7 +23,7 @@ int svc_type_from_string(const char *type)
 {
 	size_t i;
 
-	for (i = 0; i < sizeof(type_map) / sizeof(type_map[0]); ++i) {
+	for (i = 0; i < ARRAY_SIZE(type_map); ++i) {
 		if (strcmp(type_map[i], type) == 0)
 			return i;
 	}
@@ -40,7 +40,7 @@ int svc_target_from_string(const char *target)
 {
 	size_t i;
 
-	for (i = 0; i < sizeof(target_map) / sizeof(target_map[0]); ++i) {
+	for (i = 0; i < ARRAY_SIZE(target_map); ++i) {
 		if (strcmp(target_map[i], target) == 0)
 			return i;
 	}

lib/init/svcscan.c

@@ -11,7 +11,7 @@
 
 #include "service.h"
 
-int svcscan(const char *directory, service_list_t *list)
+int svcscan(const char *directory, service_list_t *list, int flags)
 {
 	int i, dfd, type, ret = 0;
 	struct dirent *ent;
@@ -66,7 +66,7 @@ int svcscan(const char *directory, service_list_t *list)
 		if (type != S_IFREG && type != S_IFLNK)
 			continue;
 
-		svc = rdsvc(dfd, ent->d_name);
+		svc = rdsvc(dfd, ent->d_name, flags);
 		if (svc == NULL) {
 			ret = -1;
 			continue;

lib/libcfg/rdcfg.c

@@ -47,7 +47,8 @@ static int splitkv(rdline_t *rd, char **k, char **v)
 	return 0;
 }
 
-int rdcfg(void *cfgobj, rdline_t *rd, const cfg_param_t *params, size_t count)
+int rdcfg(void *cfgobj, rdline_t *rd, const cfg_param_t *params, size_t count,
+	  int flags)
 {
 	const cfg_param_t *p;
 	char *key, *value;
@@ -66,7 +67,7 @@ int rdcfg(void *cfgobj, rdline_t *rd, const cfg_param_t *params, size_t count)
 				;
 
 			if (*value != '\0') {
-				ret = p->handle(cfgobj, value, rd);
+				ret = p->handle(cfgobj, value, rd, flags);
 				if (ret)
 					return -1;
 			}
@@ -74,7 +75,7 @@ int rdcfg(void *cfgobj, rdline_t *rd, const cfg_param_t *params, size_t count)
 			while ((ret = rdline(rd)) == 0) {
 				if (strcmp(rd->line, "}") == 0)
 					break;
-				if (p->handle(cfgobj, rd->line, rd))
+				if (p->handle(cfgobj, rd->line, rd, flags))
 					return -1;
 			}
 
@@ -82,7 +83,7 @@ int rdcfg(void *cfgobj, rdline_t *rd, const cfg_param_t *params, size_t count)
 				return -1;
 			if (ret > 0)
 				goto fail_bra;
-		} else if (p->handle(cfgobj, value, rd)) {
+		} else if (p->handle(cfgobj, value, rd, flags)) {
 			return -1;
 		}
 	}

lib/libcfg/rdline.c

@@ -8,6 +8,7 @@
 #include <fcntl.h>
 
 #include "libcfg.h"
+#include "util.h"
 
 int rdline_init(rdline_t *t, int dirfd, const char *filename,
 		int argc, const char *const *argv)

lib/util/argv_exec.c

@@ -0,0 +1,51 @@
+/* SPDX-License-Identifier: ISC */
+#include "service.h"
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <fcntl.h>
+#include <stdio.h>
+
+int setup_tty(const char *tty, bool truncate)
+{
+	int fd;
+
+	if (tty == NULL)
+		return 0;
+
+	fd = open(tty, O_RDWR);
+	if (fd < 0) {
+		perror(tty);
+		return -1;
+	}
+
+	if (truncate)
+		ftruncate(fd, 0);
+
+	close(STDIN_FILENO);
+	close(STDOUT_FILENO);
+	close(STDERR_FILENO);
+
+	setsid();
+
+	dup2(fd, STDIN_FILENO);
+	dup2(fd, STDOUT_FILENO);
+	dup2(fd, STDERR_FILENO);
+	close(fd);
+	return 0;
+}
+
+void argv_exec(exec_t *e)
+{
+	char **argv = alloca(sizeof(char *) * (e->argc + 1)), *ptr;
+	int i;
+
+	for (ptr = e->args, i = 0; i < e->argc; ++i, ptr += strlen(ptr) + 1)
+		argv[i] = ptr;
+
+	argv[i] = NULL;
+	execvp(argv[0], argv);
+	perror(argv[0]);
+	exit(EXIT_FAILURE);
+}