minit, a Minimal init system.

1 files changed, 300 insertions, 0 deletions

diff --git a/init/msvc.c b/init/msvc.c
new file mode 100644
index 0000000..d72ddce
--- /dev/null
+++ b/init/msvc.c
@@ -0,0 +1,300 @@
+/*
+ *  minit version 0.9.1 by Felix von Leitner
+ *  ported to busybox by Glenn McGrath <bug1@optushome.com.au>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <sys/fcntl.h>
+#include <sys/file.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "busybox.h"
+
+static int infd, outfd;
+
+static char buf[1500];
+
+static unsigned int fmt_ulong(char *dest, unsigned long i)
+{
+	register unsigned long len, tmp, len2;
+
+	/* first count the number of bytes needed */
+	for (len = 1, tmp = i; tmp > 9; ++len)
+		tmp /= 10;
+	if (dest)
+		for (tmp = i, dest += len, len2 = len + 1; --len2; tmp /= 10)
+			*--dest = (tmp % 10) + '0';
+	return len;
+}
+
+static void addservice(char *service)
+{
+	char *service_ptr;
+
+	if (strncmp(service, "/etc/minit/", 11) == 0) {
+		service += 11;
+	}
+
+	while ((service_ptr = last_char_is(service, '/')) != NULL) {
+		*service_ptr = 0;
+	}
+	strncpy(buf + 1, service, 1400);
+	buf[1400] = 0;
+}
+
+static int addreadwrite(char *service)
+{
+	addservice(service);
+	write(infd, buf, strlen(buf));
+	return read(outfd, buf, 1500);
+}
+
+/* return PID, 0 if error */
+static pid_t __readpid(char *service)
+{
+	int len;
+
+	buf[0] = 'p';
+	len = addreadwrite(service);
+	if (len < 0)
+		return 0;
+	buf[len] = 0;
+	return atoi(buf);
+}
+
+/* return nonzero if error */
+static int respawn(char *service, int yesno)
+{
+	int len;
+
+	buf[0] = yesno ? 'R' : 'r';
+	len = addreadwrite(service);
+	return (len != 1 || buf[0] == '0');
+}
+
+/* return nonzero if error */
+static int startservice(char *service)
+{
+	int len;
+
+	buf[0] = 's';
+	len = addreadwrite(service);
+	return (len != 1 || buf[0] == '0');
+}
+
+extern int msvc_main(int argc, char **argv)
+{
+	if (argc < 2) {
+		bb_show_usage();
+	}
+	infd = bb_xopen("/etc/minit/in", O_WRONLY);
+	outfd = bb_xopen("/etc/minit/out", O_RDONLY);
+
+	while (lockf(infd, F_LOCK, 1)) {
+		bb_perror_msg("could not aquire lock!\n");
+		sleep(1);
+	}
+
+	if (argc == 2) {
+		pid_t pid = __readpid(argv[1]);
+
+		if (buf[0] != '0') {
+			int len;
+			int up_time;
+
+			printf("%s: ", argv[1]);
+			if (pid == 0)
+				printf("down ");
+			else if (pid == 1)
+				printf("finished ");
+			else {
+				printf("up (pid %d) ", pid);
+			}
+
+			buf[0] = 'u';
+			len = addreadwrite(argv[1]);
+			if (len < 0) {
+				up_time = 0;
+			} else {
+				buf[len] = 0;
+				up_time = atoi(buf);
+			}
+			printf("%d seconds\n", up_time);
+
+			if (pid == 0)
+				return 2;
+			else if (pid == 1)
+				return 3;
+			else
+				return 0;
+		} else {
+			bb_error_msg_and_die("no such service");
+		}
+	} else {
+		int i;
+		int ret = 0;
+		int sig = 0;
+		pid_t pid;
+
+		if (argv[1][0] == '-') {
+			switch (argv[1][1]) {
+			case 'g':
+				for (i = 2; i < argc; ++i) {
+					pid = __readpid(argv[i]);
+					if (pid < 2) {
+						if (pid == 1) {
+							bb_error_msg("%s, service termination", argv[i]);
+						} else {
+							bb_error_msg("%s, no such service", argv[i]);
+						}
+						ret = 1;
+					}
+					printf("%d\n", pid);
+				}
+				break;
+			case 'p':
+				sig = SIGSTOP;
+				goto dokill;
+				break;
+			case 'c':
+				sig = SIGCONT;
+				goto dokill;
+				break;
+			case 'h':
+				sig = SIGHUP;
+				goto dokill;
+				break;
+			case 'a':
+				sig = SIGALRM;
+				goto dokill;
+				break;
+			case 'i':
+				sig = SIGINT;
+				goto dokill;
+				break;
+			case 't':
+				sig = SIGTERM;
+				goto dokill;
+				break;
+			case 'k':
+				sig = SIGKILL;
+				goto dokill;
+				break;
+			case 'o':
+				for (i = 2; i < argc; ++i)
+					if (startservice(argv[i]) || respawn(argv[i], 0)) {
+						bb_error_msg("Couldnt not start %s\n", argv[i]);
+						ret = 1;
+					}
+				break;
+			case 'd':
+				for (i = 2; i < argc; ++i) {
+					pid = __readpid(argv[i]);
+					if (pid == 0) {
+						bb_error_msg("%s, no such service\n", argv[i]);
+						ret = 1;
+					} else if (pid == 1)
+						continue;
+					if (respawn(argv[i], 0) || kill(pid, SIGTERM)
+						|| kill(pid, SIGCONT));
+				}
+				break;
+			case 'u':
+				for (i = 2; i < argc; ++i) {
+					if (startservice(argv[i]) || respawn(argv[i], 1)) {
+						bb_error_msg("Couldnt not start %s\n", argv[i]);
+						ret = 1;
+					}
+					break;
+				}
+			case 'C':
+				for (i = 2; i < argc; ++i) {
+					int len;
+
+					buf[0] = 'C';
+					len = addreadwrite(argv[i]);
+					if (len != 1 || buf[0] == '0') {
+						bb_error_msg("%s has terminated or was killed\n",
+									 argv[i]);
+						ret = 1;
+					}
+				}
+				break;
+			case 'P':
+				pid = atoi(argv[1] + 2);
+				if (pid > 1) {
+					char *tmp;
+					int len;
+
+					buf[0] = 'P';
+					addservice(argv[2]);
+					tmp = buf + strlen(buf) + 1;
+					tmp[fmt_ulong(tmp, pid)] = 0;
+					write(infd, buf, strlen(buf) + strlen(tmp) + 2);
+					len = read(outfd, buf, 1500);
+					if (len != 1 || buf[0] == '0') {
+						bb_error_msg_and_die("Couldnt not set pid of service %s\n", argv[2]);
+					}
+				}
+				break;
+			default:
+				bb_show_usage();
+			}
+		} else {
+			bb_show_usage();
+		}
+		return ret;
+dokill:
+		for (i = 2; i < argc; i++) {
+			pid = __readpid(argv[i]);
+			if (!pid) {
+				bb_error_msg("%s no such service\n", argv[i]);
+				ret = 1;
+			}
+			if (kill(pid, sig)) {
+				bb_error_msg("%s, could not send signal %d to PID %d\n",
+							 argv[i], sig, pid);
+				ret = 1;
+			}
+		}
+		return ret;
+	}
+}
+
+/*
+  -u   Up.  If the service is not running, start it.  If the service stops,
+       restart it.
+  -d   Down.  If the service is running, send it a TERM signal and then a CONT
+       signal.  After it stops, do not restart it.
+  -o   Once.  If the service is not running, start it.  Do not restart it if it
+       stops.
+  -r   Tell supervise that the service is normally running; this affects status
+       messages.
+  -s   Tell supervise that the service is normally stopped; this affects status
+       messages.
+  -p   Pause.  Send the service a STOP signal.
+  -c   Continue.  Send the service a CONT signal.
+  -h   Hangup.  Send the service a HUP signal.
+  -a   Alarm.  Send the service an ALRM signal.
+  -i   Interrupt.  Send the service an INT signal.
+  -t   Terminate.  Send the service a TERM signal.
+  -k   Kill.  Send the service a KILL signal.
+  -x   Exit.  supervise will quit as soon as the service is down.
+*/