fixup! Add service(8).

init/.gitignore

@@ -1,2 +1,2 @@
 init
-*.o
+service

init/service.c

@@ -0,0 +1,123 @@
+/*
+ * Copyright (c) 2024 Jonas 'Sortie' Termansen.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ * service.c
+ * Start and stop services.
+ */
+
+#include <sys/socket.h>
+#include <sys/un.h>
+
+#include <err.h>
+#include <getopt.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <unistd.h>
+
+static int open_local_client_socket(const char* path, int flags)
+{
+	size_t path_length = strlen(path);
+	size_t addr_size = offsetof(struct sockaddr_un, sun_path) + path_length + 1;
+	struct sockaddr_un* sockaddr = malloc(addr_size);
+	if ( !sockaddr )
+		return -1;
+	sockaddr->sun_family = AF_LOCAL;
+	strcpy(sockaddr->sun_path, path);
+	int fd = socket(AF_LOCAL, SOCK_STREAM | flags, 0);
+	if ( fd < 0 )
+		return free(sockaddr), -1;
+	if ( connect(fd, (const struct sockaddr*) sockaddr, addr_size) < 0 )
+		return close(fd), free(sockaddr), -1;
+	free(sockaddr);
+	return fd;
+}
+
+int main(int argc, char* argv[])
+{
+	const char* init_socket = getenv("INIT_SOCKET");
+	if ( !init_socket )
+		init_socket = "/var/run/init";
+
+	bool raw = false;
+	const char* source = "local";
+	
+	const struct option longopts[] =
+	{
+		{"source", required_argument, NULL, 't'},
+		{"raw", no_argument, NULL, 'r'},
+		{0, 0, 0, 0}
+	};
+	const char* opts = "rs:";
+	int opt;
+	while ( (opt = getopt_long(argc, argv, opts, longopts, NULL)) != -1 )
+	{
+		switch ( opt )
+		{
+		case 'r': raw = true; break;
+		case 's': source = optarg; break;
+		default: return 2;
+		}
+	}
+
+	int fd = open_local_client_socket(init_socket, 0);
+	if ( fd < 0 )
+		err(1, "%s", init_socket);
+
+	if ( raw )
+	{
+		for ( int i = optind; i < argc; i++ )
+		{
+			if ( dprintf(fd, "%s%c", argv[i], i + 1 == argc ? '\n' : ' ') < 0 )
+				err(1, "%s", init_socket);
+		}
+		return 0;
+	}
+
+	if ( argc - optind < 2 )
+		errx(1, "usage: <daemon> <command>");
+
+	const char* daemon = argv[optind++];
+	const char* command = argv[optind++];
+
+	if ( !strcmp(command, "enable") )
+	{
+		// TODO: Option for not writing out a new config.
+		if ( dprintf(fd, "require %s %s start\n", source, daemon) < 0 )
+			err(1, "%s", init_socket);
+	}
+	else if ( !strcmp(command, "disable") )
+	{
+		// TODO: Option for not writing out a new config.
+		if ( dprintf(fd, "unrequire %s %s\n", source, daemon) < 0 )
+			err(1, "%s", init_socket);
+	}
+	else if ( !strcmp(command, "start") )
+	{
+		if ( dprintf(fd, "require %s %s start\n", source, daemon) < 0 )
+			err(1, "%s", init_socket);
+	}
+	else if ( !strcmp(command, "stop") )
+	{
+		if ( dprintf(fd, "unrequire %s %s stop\n", source, daemon) < 0 )
+			err(1, "%s", init_socket);
+	}
+	else
+		errx(1, "unknown command: %s", command);
+
+	return 0;
+}