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authorDavid Oberhollenzer <david.oberhollenzer@tele2.at>2018-02-25 14:33:19 +0100
committerDavid Oberhollenzer <david.oberhollenzer@tele2.at>2018-03-24 17:04:20 +0100
commit9a88f7da453eadc72d8f333700dbd80777feecd1 (patch)
tree8a096e37123ece1d20bcb4d0ae8e064bdd39747a /initd/main.c
Initial commit
Signed-off-by: David Oberhollenzer <david.oberhollenzer@tele2.at>
Diffstat (limited to 'initd/main.c')
-rw-r--r--initd/main.c238
1 files changed, 238 insertions, 0 deletions
diff --git a/initd/main.c b/initd/main.c
new file mode 100644
index 0000000..211188e
--- /dev/null
+++ b/initd/main.c
@@ -0,0 +1,238 @@
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <sys/socket.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <errno.h>
+#include <poll.h>
+
+#include <sys/signalfd.h>
+
+#include "init.h"
+
+static service_list_t cfg;
+
+static int target = TGT_BOOT; /* runlevel we are targetting */
+static int runlevel = -1; /* runlevel we are currently on */
+
+static void handle_exited(service_t *svc)
+{
+ switch (svc->type) {
+ case SVC_RESPAWN:
+ if (target == TGT_REBOOT || target == TGT_SHUTDOWN) {
+ delsrv(svc);
+ break;
+ }
+
+ svc->pid = runlst(svc->exec, svc->num_exec, svc->ctty);
+ if (svc->pid == -1) {
+ print_status(svc->desc, STATUS_FAIL, false);
+ delsrv(svc);
+ }
+
+ svclist_add(svc);
+ break;
+ case SVC_ONCE:
+ print_status(svc->desc,
+ svc->status == EXIT_SUCCESS ?
+ STATUS_OK : STATUS_FAIL, false);
+ /* fall-through */
+ default:
+ delsrv(svc);
+ break;
+ }
+}
+
+static void handle_signal(int sigfd)
+{
+ struct signalfd_siginfo info;
+ service_t *svc;
+ int status;
+ pid_t pid;
+
+ if (read(sigfd, &info, sizeof(info)) != sizeof(info)) {
+ perror("read on signal fd");
+ return;
+ }
+
+ switch (info.ssi_signo) {
+ case SIGCHLD:
+ for (;;) {
+ pid = waitpid(-1, &status, WNOHANG);
+ if (pid <= 0)
+ break;
+
+ status = WIFEXITED(status) ? WEXITSTATUS(status) :
+ EXIT_FAILURE;
+
+ svc = svclist_remove(pid);
+
+ if (svc != NULL)
+ handle_exited(svc);
+ }
+ break;
+ case SIGINT:
+ /* TODO: ctrl-alt-del */
+ break;
+ }
+}
+
+static void start_runlevel(int level)
+{
+ service_t *svc;
+ int status;
+
+ while (cfg.targets[level] != NULL) {
+ svc = cfg.targets[level];
+ cfg.targets[level] = svc->next;
+
+ if (!svc->num_exec) {
+ print_status(svc->desc, STATUS_OK, false);
+ delsrv(svc);
+ continue;
+ }
+
+ if (svc->type == SVC_WAIT) {
+ print_status(svc->desc, STATUS_WAIT, false);
+
+ status = runlst_wait(svc->exec, svc->num_exec,
+ svc->ctty);
+
+ print_status(svc->desc,
+ status == EXIT_SUCCESS ?
+ STATUS_OK : STATUS_FAIL,
+ true);
+ delsrv(svc);
+ } else {
+ svc->pid = runlst(svc->exec, svc->num_exec, svc->ctty);
+ if (svc->pid == -1) {
+ print_status(svc->desc, STATUS_FAIL, false);
+ delsrv(svc);
+ continue;
+ }
+
+ svclist_add(svc);
+ }
+ }
+}
+
+static int read_msg(int fd, ti_msg_t *msg)
+{
+ ssize_t ret;
+retry:
+ ret = read(fd, msg, sizeof(*msg));
+
+ if (ret < 0) {
+ if (errno == EINTR)
+ goto retry;
+ perror("read on telinit socket");
+ return -1;
+ }
+
+ if ((size_t)ret < sizeof(*msg)) {
+ fputs("short read on telinit socket", stderr);
+ return -1;
+ }
+
+ return 0;
+}
+
+static void handle_tellinit(int ti_sock)
+{
+ ti_msg_t msg;
+ int fd;
+
+ fd = accept(ti_sock, NULL, NULL);
+ if (fd == -1)
+ return;
+
+ if (read_msg(fd, &msg)) {
+ close(fd);
+ return;
+ }
+
+ switch (msg.type) {
+ case TI_SHUTDOWN:
+ target = TGT_SHUTDOWN;
+ break;
+ case TI_REBOOT:
+ target = TGT_REBOOT;
+ break;
+ }
+
+ close(fd);
+}
+
+int main(void)
+{
+ int ti_sock, sfd, ret;
+ struct pollfd pfd[2];
+ sigset_t mask;
+
+ if (getpid() != 1) {
+ fputs("init does not have pid 1, terminating!\n", stderr);
+ return EXIT_FAILURE;
+ }
+
+ if (reboot(LINUX_REBOOT_CMD_CAD_OFF))
+ perror("cannot disable CTRL+ALT+DEL");
+
+ if (srvscan(SVCDIR, &cfg)) {
+ fputs("Error reading service list from " SVCDIR "\n"
+ "Trying to continue anyway\n", stderr);
+ }
+
+ sigfillset(&mask);
+ if (sigprocmask(SIG_SETMASK, &mask, NULL) == -1) {
+ perror("sigprocmask");
+ return EXIT_FAILURE;
+ }
+
+ sfd = signalfd(-1, &mask, SFD_CLOEXEC);
+ if (sfd == -1) {
+ perror("signalfd");
+ return EXIT_FAILURE;
+ }
+
+ ti_sock = mksock();
+ if (ti_sock == -1)
+ return EXIT_FAILURE;
+
+ if (setup_tty())
+ return EXIT_FAILURE;
+
+ memset(pfd, 0, sizeof(pfd));
+ pfd[0].fd = sfd;
+ pfd[1].fd = ti_sock;
+ pfd[0].events = pfd[1].events = POLLIN;
+
+ for (;;) {
+ if (!svclist_have_singleshot()) {
+ if (target != runlevel) {
+ start_runlevel(target);
+ runlevel = target;
+ continue;
+ }
+
+ if (runlevel == TGT_SHUTDOWN)
+ do_shutdown(RB_POWER_OFF);
+
+ if (runlevel == TGT_REBOOT)
+ do_shutdown(RB_AUTOBOOT);
+ }
+
+ ret = poll(pfd, sizeof(pfd) / sizeof(pfd[0]), -1);
+
+ if (ret > 0) {
+ if (pfd[0].revents & POLLIN)
+ handle_signal(sfd);
+
+ if (pfd[1].revents & POLLIN)
+ handle_tellinit(ti_sock);
+ }
+ }
+
+ return EXIT_SUCCESS;
+}