From d69d7614ea8b9720f934a94249ee8199bbcaf70c Mon Sep 17 00:00:00 2001
From: dzwdz
Date: Sat, 13 Aug 2022 17:40:44 +0200
Subject: user: add /initctl for shutting the system down in a cleaner way
---
src/user/app/init/driver/driver.h | 2 ++
src/user/app/init/driver/initctl.c | 40 ++++++++++++++++++++++++++++++++++++++
src/user/app/init/init.c | 26 +++++++++++++++++++++----
3 files changed, 64 insertions(+), 4 deletions(-)
create mode 100644 src/user/app/init/driver/initctl.c
(limited to 'src/user/app/init')
diff --git a/src/user/app/init/driver/driver.h b/src/user/app/init/driver/driver.h
index c99955a..fc9f51b 100644
--- a/src/user/app/init/driver/driver.h
+++ b/src/user/app/init/driver/driver.h
@@ -1,5 +1,7 @@
#pragma once
+#include <camellia/types.h>
+void initctl_drv(handle_t killswitch);
void ps2_drv(void);
void tmpfs_drv(void);
diff --git a/src/user/app/init/driver/initctl.c b/src/user/app/init/driver/initctl.c
new file mode 100644
index 0000000..b8fbb9b
--- /dev/null
+++ b/src/user/app/init/driver/initctl.c
@@ -0,0 +1,40 @@
+#include "driver.h"
+#include <camellia/syscalls.h>
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+
+void initctl_drv(handle_t killswitch) {
+ struct fs_wait_response res;
+ char buf[64];
+ const size_t buflen = sizeof buf;
+ while (!_syscall_fs_wait(buf, buflen, &res)) {
+ switch (res.op) {
+ case VFSOP_OPEN:
+ _syscall_fs_respond(NULL, res.len == 0 ? 0 : -1, 0);
+ break;
+ case VFSOP_WRITE:
+ /* null terminate */
+ if (res.len > buflen - 1)
+ res.len = buflen - 1;
+ buf[res.len] = '\0';
+ /* cut at first whitespace */
+ for (size_t i = 0; buf[i]; i++) {
+ if (isspace(buf[i])) {
+ buf[i] = '\0';
+ break;
+ }
+ }
+ if (!strcmp(buf, "halt")) {
+ _syscall_write(killswitch, "halt", 4, 0, 0);
+ exit(1);
+ }
+ _syscall_fs_respond(NULL, res.len, 0);
+ break;
+ default:
+ _syscall_fs_respond(NULL, -ENOSYS, 0);
+ break;
+ }
+ }
+ exit(1);
+}
diff --git a/src/user/app/init/init.c b/src/user/app/init/init.c
index 2ae8048..ee8554f 100644
--- a/src/user/app/init/init.c
+++ b/src/user/app/init/init.c
@@ -25,6 +25,8 @@ void redirect(const char *exe, const char *out, const char *in) {
}
int main(void) {
+ handle_t killswitch_pipe[2];
+
freopen("/kdev/com1", "a+", stdout);
freopen("/kdev/com1", "a+", stderr);
printf("in init (stage 2), main at 0x%x\n", &main);
@@ -50,6 +52,16 @@ int main(void) {
fs_union(list);
}
+ if (_syscall_pipe(killswitch_pipe, 0) < 0) {
+ printf("couldn't create the killswitch pipe, quitting...\n");
+ return 1;
+ }
+ MOUNT_AT("/initctl") {
+ close(killswitch_pipe[0]);
+ initctl_drv(killswitch_pipe[1]);
+ }
+ close(killswitch_pipe[1]);
+
if (fork()) {
/* used to trigger a kernel bug
* 7c96f9c03502e0c60f23f4c550d12a629f3b3daf */
@@ -57,10 +69,16 @@ int main(void) {
exit(1);
}
- redirect("/bin/shell", "/kdev/com1", "/kdev/com1");
- redirect("/bin/shell", "/vtty", "/keyboard");
+ if (!fork()) {
+ // TODO close on exec
+ close(killswitch_pipe[0]);
+ redirect("/bin/shell", "/kdev/com1", "/kdev/com1");
+ redirect("/bin/shell", "/vtty", "/keyboard");
+ _syscall_await();
+ printf("init: restarting children not yet implemented\n");
+ exit(1);
+ }
- _syscall_await();
- printf("init: quitting\n");
+ _syscall_read(killswitch_pipe[0], NULL, 0, 0);
return 0;
}
--
cgit v1.2.3