aboutsummaryrefslogtreecommitdiff
path: root/toys/pending
diff options
context:
space:
mode:
Diffstat (limited to 'toys/pending')
-rw-r--r--toys/pending/init.c470
1 files changed, 470 insertions, 0 deletions
diff --git a/toys/pending/init.c b/toys/pending/init.c
new file mode 100644
index 00000000..facf3b57
--- /dev/null
+++ b/toys/pending/init.c
@@ -0,0 +1,470 @@
+/* init.c - init program.
+ *
+ * Copyright 2012 Harvind Singh <harvindsingh1981@gmail.com>
+ * Copyright 2013 Kyungwan Han <asura321@gmail.com>
+ *
+ * No Standard
+
+USE_INIT(NEWTOY(init, "", TOYFLAG_SBIN))
+
+config INIT
+ bool "init"
+ default n
+ help
+ usage: init
+
+ init the system.
+*/
+
+#include "toys.h"
+#include<linux/vt.h>
+#include<sys/reboot.h>
+
+struct action_list_seed {
+ struct action_list_seed *next;
+ pid_t pid;
+ uint8_t action;
+ char *terminal_name;
+ char *command;
+};
+struct action_list_seed *action_list_pointer = NULL;
+int caught_signal;
+
+//INITTAB action defination
+#define SYSINIT 0x01
+#define WAIT 0x02
+#define ONCE 0x04
+#define RESPAWN 0x08
+#define ASKFIRST 0x10
+#define CTRLALTDEL 0x20
+#define SHUTDOWN 0x40
+#define RESTART 0x80
+
+static void initialize_console(void)
+{
+ int fd;
+ char *p = (p = getenv("CONSOLE")) ? p : getenv("console");
+ if (!p) {
+ fd = open("/dev/null", O_RDWR);
+ if (fd >= 0) {
+ while(fd < 2) fd = dup(fd);
+ while(fd > 2) close(fd--);
+ }
+ } else {
+ fd = open(p, O_RDWR | O_NONBLOCK | O_NOCTTY);
+ if (fd < 0) xprintf("Unable to open console %s\n",p);
+ else {
+ dup2(fd,0);
+ dup2(fd,1);
+ dup2(fd,2);
+ }
+ }
+ p = getenv("TERM");
+#ifdef VT_OPENQRY
+ int terminal_no;
+ if (ioctl(0, VT_OPENQRY, &terminal_no)) {
+ if (!p || !strcmp(p,"linux")) putenv((char*)"TERM=vt102");
+ } else
+#endif
+ if (!p) putenv((char*)"TERM=linux");
+}
+
+static void set_sane_term(void)
+{
+ struct termios terminal;
+ tcgetattr(0, &terminal);
+ terminal.c_cc[VINTR] = 3;//ctrl-c
+ terminal.c_cc[VQUIT] = 28;/*ctrl-\*/
+ terminal.c_cc[VERASE] = 127;//ctrl-?
+ terminal.c_cc[VKILL] = 21;//ctrl-u
+ terminal.c_cc[VEOF] = 4;//ctrl-d
+ terminal.c_cc[VSTART] = 17;//ctrl-q
+ terminal.c_cc[VSTOP] = 19;//ctrl-s
+ terminal.c_cc[VSUSP] = 26;//ctrl-z
+
+ terminal.c_line = 0;
+ terminal.c_cflag = terminal.c_cflag&(CRTSCTS|PARODD|PARENB|CSTOPB|CSIZE|CBAUDEX|CBAUD);
+ terminal.c_cflag = terminal.c_cflag|(CLOCAL|HUPCL|CREAD);
+ terminal.c_iflag = IXON|IXOFF|ICRNL;//enable start/stop input and output control + map CR to NL on input
+ terminal.c_oflag = ONLCR|OPOST;//Map NL to CR-NL on output
+ terminal.c_lflag = IEXTEN|ECHOKE|ECHOCTL|ECHOK|ECHOE|ECHO|ICANON|ISIG;
+ tcsetattr(0, TCSANOW, &terminal);
+}
+
+static void set_enviornment(void)
+{
+ putenv((char*)"HOME=/");
+ putenv((char*)"PATH=/sbin:/usr/sbin:/bin:/usr/bin");
+ putenv((char*)"SHELL=/bin/sh");
+ putenv((char*)"USER=root");
+}
+
+static void add_new_action(uint8_t action,char *command,char *term)
+{
+ struct action_list_seed *x,**y;
+ y = &action_list_pointer;
+ x = *y;
+ while(x) {
+ if (!(strcmp(x->command,command)) && !(strcmp(x->terminal_name,term))) {
+ *y = x->next;//remove from the list
+ while(*y) y = &(*y)->next;//traverse through list till end
+ x->next = NULL;
+ break;
+ }
+ y = &(x)->next;
+ x = *y;
+ }
+ //create a new node
+ if (!x) {
+ x = xzalloc(sizeof(*x));
+ x->command = xstrdup(command);
+ x->terminal_name = xstrdup(term);
+ }
+ x->action = action;
+ *y = x;
+}
+
+static void inittab_parsing(void)
+{
+ int i, fd, line_number = 0, token_count = 0;
+ char *p, *q, *extracted_token, *tty_name = NULL, *command = NULL, *tmp;
+ uint8_t action = 0;
+ char *act_name = "sysinit\0wait\0once\0respawn\0askfirst\0ctrlaltdel\0"
+ "shutdown\0restart\0";
+
+ fd = open("/etc/inittab", O_RDONLY);
+ if (fd < 0) {
+ error_msg("Unable to open /etc/inittab. Using Default inittab");
+ add_new_action(SYSINIT, "/etc/init.d/rcS", "");
+ add_new_action(RESPAWN, "/sbin/getty -n -l /bin/sh -L 115200 tty1 vt100", "");
+ } else {
+ while((q = p = get_line(fd))) { //read single line from /etc/inittab
+ char *x;
+ if((x = strchr(p, '#'))) *x = '\0';
+ line_number++;
+ token_count = 0;
+ action = 0;
+ while((extracted_token = strsep(&p,":"))) {
+ token_count++;
+ switch (token_count) {
+ case 1:
+ if (*extracted_token) {
+ if(!strncmp(extracted_token, "/dev/", 5))
+ tty_name = xmsprintf("%s",extracted_token);
+ else tty_name = xmsprintf("/dev/%s",extracted_token);
+ } else tty_name = xstrdup("");
+ break;
+ case 2:
+ break;
+ case 3:
+ for(tmp = act_name, i = 0; *tmp; i++, tmp += strlen(tmp) +1) {
+ if ( !strcmp(tmp, extracted_token)) {
+ action = 1 << i;
+ break;
+ }
+ }
+ if (!*tmp) error_msg("Invalid action at line number %d ---- ignoring",line_number);
+ break;
+ case 4:
+ command = xstrdup(extracted_token);
+ break;
+ default:
+ error_msg("Bad inittab entry at line %d", line_number);
+ break;
+ }
+ } //while token
+ if (q) free(q);
+ if (token_count != 4) continue;
+ if (action) add_new_action(action, command, tty_name);
+ free(tty_name);
+ free(command);
+ }//while line
+ close(fd);
+ }
+}
+
+static void run_command(char *command)
+{
+ char *final_command[128];
+ int hyphen = (command[0]=='-');
+
+ command = command + hyphen;
+ if (!strpbrk(command, "?<>'\";[]{}\\|=()*&^$!`~")) {
+ char *next_command;
+ char *extracted_command;
+ int x = 0;
+ next_command = strncpy(toybuf, command - hyphen, sizeof(toybuf));
+ next_command[sizeof(toybuf) - 1] = toybuf[sizeof(toybuf) - 1 ] = '\0';
+ command = next_command + hyphen;
+ while((extracted_command = strsep(&next_command," \t"))) {
+ if (*extracted_command) {
+ final_command[x] = extracted_command;
+ x++;
+ }
+ }
+ final_command[x] = NULL;
+ } else {
+ snprintf(toybuf, sizeof(toybuf), "exec %s", command);
+ command = "-/bin/sh"+1;
+ final_command[0] = (char*)("-/bin/sh"+!hyphen);
+ final_command[1] = (char*)"-c";
+ final_command[2] = toybuf;
+ final_command[3] = NULL;
+ }
+ if (hyphen) ioctl(0, TIOCSCTTY, 0);
+ execvp(command, final_command);
+ error_msg("unable to run %s",command);
+}
+
+//runs all same type of actions
+static pid_t final_run(struct action_list_seed *x)
+{
+ pid_t pid;
+ int fd;
+ sigset_t signal_set;
+
+ sigfillset(&signal_set);
+ sigprocmask(SIG_BLOCK, &signal_set, NULL);
+ if (x->action & ASKFIRST) pid = fork();
+ else pid = vfork();
+ if (pid > 0) {
+ //parent process or error
+ //unblock the signals
+ sigfillset(&signal_set);
+ sigprocmask(SIG_UNBLOCK, &signal_set, NULL);
+ return pid;
+ } else if (pid < 0) perror_exit("fork fail");
+ //new born child process
+ sigset_t signal_set_c;
+ sigfillset(&signal_set_c);
+ sigprocmask(SIG_UNBLOCK, &signal_set_c, NULL);
+ setsid();//new session
+ if (x->terminal_name[0]) {
+ close(0);
+ fd = open(x->terminal_name,(O_RDWR|O_NONBLOCK),0600);
+ if (fd != 0) {
+ error_msg("Unable to open %s,%s\n",x->terminal_name,strerror(errno));
+ _exit(EXIT_FAILURE);
+ } else {
+ dup2(0,1);
+ dup2(0,2);
+ }
+ }
+ set_sane_term();
+ run_command(x->command);
+ _exit(-1);
+}
+
+static struct action_list_seed* mark_as_terminated_process(pid_t pid)
+{
+ struct action_list_seed *x;
+ if (pid > 0) {
+ for (x = action_list_pointer; x; x = x->next) {
+ if (x->pid == pid) {
+ x->pid = 0;
+ return x;
+ }
+ }
+ }
+ return NULL;
+}
+
+static void waitforpid(pid_t pid)
+{
+ if (pid <= 0) return;
+ for(;;) {
+ pid_t y = wait(NULL);
+ mark_as_terminated_process(y);
+ if (kill(y,0)) break;
+ }
+}
+static void run_action_from_list(int action)
+{
+ pid_t pid;
+ struct action_list_seed *x = action_list_pointer;
+ for (; x; x = x->next) {
+ if (!(x->action & action)) continue;
+ if (x->action & (SHUTDOWN|ONCE|SYSINIT|CTRLALTDEL|WAIT)) {
+ pid = final_run(x);
+ if (x->action & (SHUTDOWN|SYSINIT|CTRLALTDEL|WAIT)) waitforpid(pid);
+ }
+ if (x->action & (ASKFIRST|RESPAWN))
+ if (!(x->pid)) x->pid = final_run(x);
+ }
+}
+
+static void set_defualt(void)
+{
+ sigset_t signal_set_c;
+
+ signal(SIGUSR1,SIG_DFL);
+ signal(SIGUSR2,SIG_DFL);
+ signal(SIGTERM,SIG_DFL);
+ signal(SIGQUIT,SIG_DFL);
+ signal(SIGINT,SIG_DFL);
+ signal(SIGHUP,SIG_DFL);
+ signal(SIGTSTP,SIG_DFL);
+ signal(SIGSTOP,SIG_DFL);
+ sigfillset(&signal_set_c);
+ sigprocmask(SIG_UNBLOCK,&signal_set_c, NULL);
+ run_action_from_list(SHUTDOWN);
+ error_msg("The system is going down NOW!");
+ kill(-1, SIGTERM);
+ error_msg("Sent SIGTERM to all processes");
+ sync();
+ sleep(1);
+ kill(-1,SIGKILL);
+ sync();
+}
+
+static void halt_poweroff_reboot_handler(int sig_no)
+{
+ unsigned int reboot_magic_no = 0;
+ pid_t pid;
+ set_defualt();
+ switch (sig_no) {
+ case SIGUSR1:
+ error_msg("Requesting system halt");
+ reboot_magic_no=RB_HALT_SYSTEM;
+ break;
+ case SIGUSR2:
+ error_msg("Requesting system poweroff");
+ reboot_magic_no=RB_POWER_OFF;
+ break;
+ case SIGTERM:
+ error_msg("Requesting system reboot");
+ reboot_magic_no=RB_AUTOBOOT;
+ break;
+ default:
+ break;
+ }
+ sleep(1);
+ pid = vfork();
+ if (pid == 0) {
+ reboot(reboot_magic_no);
+ _exit(EXIT_SUCCESS);
+ }
+ while(1) sleep(1);
+}
+static void restart_init_handler(int sig_no)
+{
+ struct action_list_seed *x;
+ pid_t pid;
+ int fd;
+ for (x = action_list_pointer; x; x = x->next) {
+ if (!(x->action & RESTART)) continue;
+
+ set_defualt();
+ if (x->terminal_name[0]) {
+ close(0);
+ fd = open(x->terminal_name,(O_RDWR|O_NONBLOCK),0600);
+ if (fd != 0) {
+ error_msg("Unable to open %s,%s\n",x->terminal_name,strerror(errno));
+ sleep(1);
+ pid = vfork();
+ if (pid == 0) {
+ reboot(RB_HALT_SYSTEM);
+ _exit(EXIT_SUCCESS);
+ }
+ while(1) sleep(1);
+ } else {
+ dup2(0,1);
+ dup2(0,2);
+ set_sane_term();
+ run_command(x->command);
+ }
+ }
+ }
+}
+
+static void catch_signal(int sig_no)
+{
+ caught_signal = sig_no;
+ error_msg("signal seen");
+}
+
+static void pause_handler(int sig_no)
+{
+ int signal_backup,errno_backup;
+ pid_t pid;
+ errno_backup = errno;
+ signal_backup = caught_signal;
+ signal(SIGCONT, catch_signal);
+ while(1) {
+ if (caught_signal == SIGCONT) break;
+ do
+ pid = waitpid(-1,NULL,WNOHANG);
+ while((pid==-1) && (errno=EINTR));
+ mark_as_terminated_process(pid);
+ sleep(1);
+ }
+ signal(SIGCONT,SIG_DFL);
+ errno = errno_backup;
+ caught_signal = signal_backup;
+}
+
+static void assign_signal_handler(void)
+{
+ struct sigaction sig_act;
+ signal(SIGUSR1, halt_poweroff_reboot_handler);//halt
+ signal(SIGUSR2, halt_poweroff_reboot_handler);//poweroff
+ signal(SIGTERM, halt_poweroff_reboot_handler);//reboot
+ signal(SIGQUIT, restart_init_handler);//restart init
+ memset(&sig_act, 0, sizeof(sig_act));
+ sigfillset(&sig_act.sa_mask);
+ sigdelset(&sig_act.sa_mask, SIGCONT);
+ sig_act.sa_handler = pause_handler;
+ sigaction(SIGTSTP, &sig_act, NULL);
+
+ memset(&sig_act, 0, sizeof(sig_act));
+ sig_act.sa_handler = catch_signal;
+ sigaction(SIGINT, &sig_act, NULL);
+ sigaction(SIGHUP, &sig_act, NULL);
+}
+
+static int check_if_pending_signals(void)
+{
+ int signal_caught = 0;
+ while(1) {
+ int sig = caught_signal;
+ if (!sig) return signal_caught;
+ caught_signal = 0;
+ signal_caught = 1;
+ if (sig == SIGINT) run_action_from_list(CTRLALTDEL);
+ }
+}
+void init_main(void)
+{
+ if (getpid() != 1) error_exit("Already running");
+ xprintf("Started init\n");
+ initialize_console();
+ set_sane_term();
+
+ if (chdir("/")) perror_exit("Can't cd to /");
+ setsid();
+
+ set_enviornment();
+ inittab_parsing();
+ assign_signal_handler();
+ run_action_from_list(SYSINIT);
+ check_if_pending_signals();
+ run_action_from_list(WAIT);
+ check_if_pending_signals();
+ run_action_from_list(ONCE);
+ while(1) {
+ int suspected_WNOHANG;
+ suspected_WNOHANG = check_if_pending_signals();
+ run_action_from_list(RESPAWN | ASKFIRST);
+ suspected_WNOHANG = suspected_WNOHANG|check_if_pending_signals();
+ sleep(1);//let cpu breath
+ suspected_WNOHANG = suspected_WNOHANG|check_if_pending_signals();
+ if (suspected_WNOHANG) suspected_WNOHANG=WNOHANG;
+ while(1) {
+ pid_t pid;
+ pid = waitpid(-1, NULL, suspected_WNOHANG);
+ if (pid <= 0) break;
+ mark_as_terminated_process(pid);
+ suspected_WNOHANG = WNOHANG;
+ }
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-23 21:58:54 +0000