Add helpers for initd socket

Signed-off-by: David Oberhollenzer <goliath@infraroot.at>

lib/Makemodule.am

@@ -1,6 +1,8 @@
 libinit_a_SOURCES = lib/init/delsvc.c lib/init/svcmap.c lib/init/rdsvc.c
 libinit_a_SOURCES += lib/init/svcscan.c lib/init/del_svc_list.c
 libinit_a_SOURCES += lib/init/svc_tsort.c lib/include/service.h
+libinit_a_SOURCES += lib/init/init_socket_open.c lib/init/init_socket_create.c
+libinit_a_SOURCES += lib/include/initsock.h lib/init/init_socket_send_request.c
 libinit_a_CPPFLAGS = $(AM_CPPFLAGS)
 libinit_a_CFLAGS = $(AM_CFLAGS)
 

lib/include/initsock.h

@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: ISC */
+#ifndef INITSOCK_H
+#define INITSOCK_H
+
+#include "config.h"
+
+#define INIT_SOCK_PATH SOCKDIR "/init.sock"
+
+typedef enum {
+	EIR_STATUS = 0x00,
+} E_INIT_REQUEST;
+
+typedef struct {
+	E_INIT_REQUEST rq;
+} init_request_t;
+
+int init_socket_create(void);
+
+int init_socket_open(const char *tmppath);
+
+int init_socket_send_request(int fd, E_INIT_REQUEST rq);
+
+#endif /* INITSOCK_H */

lib/init/init_socket_create.c

@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: ISC */
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <unistd.h>
+#include <stdio.h>
+
+#include "initsock.h"
+
+int init_socket_create(void)
+{
+	struct sockaddr_un un;
+	int fd;
+
+	fd = socket(AF_UNIX, SOCK_DGRAM | SOCK_CLOEXEC, 0);
+	if (fd < 0) {
+		perror("socket");
+		return -1;
+	}
+
+	memset(&un, 0, sizeof(un));
+	un.sun_family = AF_UNIX;
+
+	strcpy(un.sun_path, INIT_SOCK_PATH);
+	unlink(INIT_SOCK_PATH);
+
+	if (bind(fd, (struct sockaddr *)&un, sizeof(un))) {
+		perror("bind: " INIT_SOCK_PATH);
+		close(fd);
+		unlink(INIT_SOCK_PATH);
+		return -1;
+	}
+
+	return fd;
+}

lib/init/init_socket_open.c

@@ -0,0 +1,46 @@
+/* SPDX-License-Identifier: ISC */
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <unistd.h>
+#include <string.h>
+#include <errno.h>
+#include <stdio.h>
+
+#include "initsock.h"
+
+int init_socket_open(const char *tmppath)
+{
+	struct sockaddr_un un;
+	int fd;
+
+	fd = socket(AF_UNIX, SOCK_DGRAM | SOCK_CLOEXEC, 0);
+	if (fd < 0) {
+		perror("socket");
+		return -1;
+	}
+
+	memset(&un, 0, sizeof(un));
+	un.sun_family = AF_UNIX;
+
+	strcpy(un.sun_path, tmppath);
+
+	if (bind(fd, (struct sockaddr *)&un, sizeof(un))) {
+		fprintf(stderr, "bind: %s: %s", tmppath, strerror(errno));
+		close(fd);
+		unlink(tmppath);
+		return -1;
+	}
+
+	memset(&un, 0, sizeof(un));
+	un.sun_family = AF_UNIX;
+
+	strcpy(un.sun_path, INIT_SOCK_PATH);
+
+	if (connect(fd, (struct sockaddr *)&un, sizeof(un))) {
+		perror("connect: " INIT_SOCK_PATH);
+		close(fd);
+		return -1;
+	}
+
+	return fd;
+}

lib/init/init_socket_send_request.c

@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: ISC */
+#include <unistd.h>
+#include <string.h>
+#include <stdio.h>
+#include <errno.h>
+
+#include "initsock.h"
+
+int init_socket_send_request(int fd, E_INIT_REQUEST rq)
+{
+	init_request_t request;
+	ssize_t ret;
+
+	memset(&request, 0, sizeof(request));
+	request.rq = rq;
+
+retry:
+	ret = write(fd, &request, sizeof(request));
+
+	if (ret < 0) {
+		if (errno == EINTR)
+			goto retry;
+		perror(INIT_SOCK_PATH);
+		return -1;
+	}
+
+	return 0;
+}