+/* vi: set sw=4 ts=4: */
/*
* Mini init implementation for busybox
*
- *
* Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>.
+ * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
* Adjusted by so many folks, it's impossible to keep track.
*
- * 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
- *
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
-#include "internal.h"
-#include <stdio.h>
-#include <stdlib.h>
-#include <stdarg.h>
-#include <unistd.h>
-#include <errno.h>
-#include <signal.h>
-#include <termios.h>
-#include <sys/types.h>
-#include <sys/fcntl.h>
-#include <sys/wait.h>
-#include <string.h>
-#include <sys/mount.h>
+#include "libbb.h"
+#include <syslog.h>
+#include <paths.h>
#include <sys/reboot.h>
-#include <sys/kdaemon.h>
-#include <sys/sysmacros.h>
-#include <linux/serial.h> /* for serial_struct */
-#include <sys/vt.h> /* for vt_stat */
-#include <sys/ioctl.h>
-
-#define VT_CONSOLE "/dev/console" /* Logical system console */
-#define VT_PRIMARY "/dev/tty1" /* Primary virtual console */
-#define VT_SECONDARY "/dev/tty2" /* Virtual console */
-#define VT_LOG "/dev/tty3" /* Virtual console */
-#define SERIAL_CON0 "/dev/ttyS0" /* Primary serial console */
-#define SERIAL_CON1 "/dev/ttyS1" /* Serial console */
-#define SHELL "/bin/sh" /* Default shell */
-#define INITSCRIPT "/etc/init.d/rcS" /* Initscript. */
-#define PATH_DEFAULT "PATH=/usr/local/sbin:/sbin:/bin:/usr/sbin:/usr/bin"
-
-#define LOG 0x1
-#define CONSOLE 0x2
-static char *console = VT_CONSOLE;
-static char *second_console = VT_SECONDARY;
-static char *log = VT_LOG;
-static int kernel_version = 0;
-
-
-/* try to open up the specified device */
-int device_open(char *device, int mode)
+
+/* Was a CONFIG_xxx option. A lot of people were building
+ * not fully functional init by switching it on! */
+#define DEBUG_INIT 0
+
+#define COMMAND_SIZE 256
+#define CONSOLE_NAME_SIZE 32
+#define MAXENV 16 /* Number of env. vars */
+
+/*
+ * When a file named CORE_ENABLE_FLAG_FILE exists, setrlimit is called
+ * before processes are spawned to set core file size as unlimited.
+ * This is for debugging only. Don't use this is production, unless
+ * you want core dumps lying about....
+ */
+#define CORE_ENABLE_FLAG_FILE "/.init_enable_core"
+#include <sys/resource.h>
+
+#define INITTAB "/etc/inittab" /* inittab file location */
+#ifndef INIT_SCRIPT
+#define INIT_SCRIPT "/etc/init.d/rcS" /* Default sysinit script. */
+#endif
+
+/* Allowed init action types */
+#define SYSINIT 0x01
+#define RESPAWN 0x02
+/* like respawn, but wait for <Enter> to be pressed on tty: */
+#define ASKFIRST 0x04
+#define WAIT 0x08
+#define ONCE 0x10
+#define CTRLALTDEL 0x20
+#define SHUTDOWN 0x40
+#define RESTART 0x80
+
+/* Set up a linked list of init_actions, to be read from inittab */
+struct init_action {
+ struct init_action *next;
+ pid_t pid;
+ uint8_t action_type;
+ char terminal[CONSOLE_NAME_SIZE];
+ char command[COMMAND_SIZE];
+};
+
+/* Static variables */
+static struct init_action *init_action_list = NULL;
+
+static const char *log_console = VC_5;
+
+enum {
+ L_LOG = 0x1,
+ L_CONSOLE = 0x2,
+
+#if ENABLE_FEATURE_EXTRA_QUIET
+ MAYBE_CONSOLE = 0x0,
+#else
+ MAYBE_CONSOLE = L_CONSOLE,
+#endif
+
+#ifndef RB_HALT_SYSTEM
+ RB_HALT_SYSTEM = 0xcdef0123, /* FIXME: this overflows enum */
+ RB_ENABLE_CAD = 0x89abcdef,
+ RB_DISABLE_CAD = 0,
+ RB_POWER_OFF = 0x4321fedc,
+ RB_AUTOBOOT = 0x01234567,
+#endif
+};
+
+/* Function prototypes */
+static void halt_reboot_pwoff(int sig) NORETURN;
+
+static void waitfor(pid_t pid)
{
- int m, f, fd = -1;
-
- m = mode | O_NONBLOCK;
-
- /* Retry up to 5 times */
- for (f = 0; f < 5; f++)
- if ((fd = open(device, m)) >= 0)
- break;
- if (fd < 0)
- return fd;
- /* Reset original flags. */
- if (m != mode)
- fcntl(fd, F_SETFL, mode);
- return fd;
+ /* waitfor(run(x)): protect against failed fork inside run() */
+ if (pid <= 0)
+ return;
+
+ /* Wait for any child (prevent zombies from exiting orphaned processes)
+ * but exit the loop only when specified one has exited. */
+ while (wait(NULL) != pid)
+ continue;
}
-/* print a message to the specified device:
- * device may be bitwise-or'd from LOG | CONSOLE */
-void message(int device, char *fmt, ...)
+static void loop_forever(void) NORETURN;
+static void loop_forever(void)
{
- int fd;
- static int log_fd=-1;
- va_list arguments;
-
- /* Take full control of the log tty, and never close it.
- * It's mine, all mine! Muhahahaha! */
- if (log_fd < 0) {
- if (log == NULL) {
- /* don't even try to log, because there is no such console */
- log_fd = -2;
- /* log to main console instead */
- device = CONSOLE;
- }
- else if ((log_fd = device_open(log, O_RDWR|O_NDELAY)) < 0) {
- log_fd=-1;
- fprintf(stderr, "Bummer, can't write to log on %s!\r\n", log);
- fflush(stderr);
- return;
- }
- }
+ while (1)
+ sleep(1);
+}
- if ( (device & LOG) && (log_fd >= 0) ) {
+/* Print a message to the specified device.
+ * "where" may be bitwise-or'd from L_LOG | L_CONSOLE
+ * NB: careful, we can be called after vfork!
+ */
+#define messageD(...) do { if (DEBUG_INIT) message(__VA_ARGS__); } while (0)
+static void message(int where, const char *fmt, ...)
+ __attribute__ ((format(printf, 2, 3)));
+static void message(int where, const char *fmt, ...)
+{
+ static int log_fd = -1;
+ va_list arguments;
+ unsigned l;
+ char msg[128];
+
+ msg[0] = '\r';
va_start(arguments, fmt);
- vdprintf(log_fd, fmt, arguments);
+ l = vsnprintf(msg + 1, sizeof(msg) - 2, fmt, arguments);
+ if (l > sizeof(msg) - 2)
+ l = sizeof(msg) - 2;
+ msg[l] = '\0';
va_end(arguments);
- }
- if (device & CONSOLE) {
- if ((fd = device_open(console, O_WRONLY|O_NOCTTY|O_NDELAY)) >= 0) {
- va_start(arguments, fmt);
- vdprintf(fd, fmt, arguments);
- va_end(arguments);
- close(fd);
+
+ if (ENABLE_FEATURE_INIT_SYSLOG) {
+ /* Log the message to syslogd */
+ if (where & L_LOG) {
+ /* don't print out "\r" */
+ openlog(applet_name, 0, LOG_DAEMON);
+ syslog(LOG_INFO, "init: %s", msg + 1);
+ closelog();
+ }
+ msg[l++] = '\n';
+ msg[l] = '\0';
} else {
- fprintf(stderr, "Bummer, can't print: ");
- va_start(arguments, fmt);
- vfprintf(stderr, fmt, arguments);
- fflush(stderr);
- va_end(arguments);
+ msg[l++] = '\n';
+ msg[l] = '\0';
+ /* Take full control of the log tty, and never close it.
+ * It's mine, all mine! Muhahahaha! */
+ if (log_fd < 0) {
+ if (!log_console) {
+ log_fd = STDERR_FILENO;
+ } else {
+ log_fd = device_open(log_console, O_WRONLY | O_NONBLOCK | O_NOCTTY);
+ if (log_fd < 0) {
+ bb_error_msg("can't log to %s", log_console);
+ where = L_CONSOLE;
+ } else {
+ close_on_exec_on(log_fd);
+ }
+ }
+ }
+ if (where & L_LOG) {
+ full_write(log_fd, msg, l);
+ if (log_fd == STDERR_FILENO)
+ return; /* don't print dup messages */
+ }
+ }
+
+ if (where & L_CONSOLE) {
+ /* Send console messages to console so people will see them. */
+ full_write(STDERR_FILENO, msg, l);
}
- }
}
+/* From <linux/serial.h> */
+struct serial_struct {
+ int type;
+ int line;
+ unsigned int port;
+ int irq;
+ int flags;
+ int xmit_fifo_size;
+ int custom_divisor;
+ int baud_base;
+ unsigned short close_delay;
+ char io_type;
+ char reserved_char[1];
+ int hub6;
+ unsigned short closing_wait; /* time to wait before closing */
+ unsigned short closing_wait2; /* no longer used... */
+ unsigned char *iomem_base;
+ unsigned short iomem_reg_shift;
+ unsigned int port_high;
+ unsigned long iomap_base; /* cookie passed into ioremap */
+ int reserved[1];
+ /* Paranoia (imagine 64bit kernel overwriting 32bit userspace stack) */
+ uint32_t bbox_reserved[16];
+};
+static void console_init(void)
+{
+ struct serial_struct sr;
+ char *s;
+
+ s = getenv("CONSOLE");
+ if (!s)
+ s = getenv("console");
+ if (s) {
+ int fd = open(s, O_RDWR | O_NONBLOCK | O_NOCTTY);
+ if (fd >= 0) {
+ dup2(fd, STDIN_FILENO);
+ dup2(fd, STDOUT_FILENO);
+ xmove_fd(fd, STDERR_FILENO);
+ }
+ messageD(L_LOG, "console='%s'", s);
+ } else {
+ /* Make sure fd 0,1,2 are not closed
+ * (so that they won't be used by future opens) */
+ bb_sanitize_stdio();
+// Users report problems
+// /* Make sure init can't be blocked by writing to stderr */
+// fcntl(STDERR_FILENO, F_SETFL, fcntl(STDERR_FILENO, F_GETFL) | O_NONBLOCK);
+ }
+
+ s = getenv("TERM");
+ if (ioctl(STDIN_FILENO, TIOCGSERIAL, &sr) == 0) {
+ /* Force the TERM setting to vt102 for serial console
+ * if TERM is set to linux (the default) */
+ if (!s || strcmp(s, "linux") == 0)
+ putenv((char*)"TERM=vt102");
+ if (!ENABLE_FEATURE_INIT_SYSLOG)
+ log_console = NULL;
+ } else if (!s)
+ putenv((char*)"TERM=linux");
+}
-/* Set terminal settings to reasonable defaults */
-void set_term( int fd)
+/* Set terminal settings to reasonable defaults.
+ * NB: careful, we can be called after vfork! */
+static void set_sane_term(void)
{
- struct termios tty;
- static const char control_characters[] = {
- '\003', '\034', '\177', '\030', '\004', '\0',
- '\1', '\0', '\021', '\023', '\032', '\0', '\022',
- '\017', '\027', '\026', '\0'
- };
+ struct termios tty;
- tcgetattr(fd, &tty);
+ tcgetattr(STDIN_FILENO, &tty);
- /* Make it be sane */
- tty.c_cflag &= CBAUD|CBAUDEX|CSIZE|CSTOPB|PARENB|PARODD;
- tty.c_cflag |= HUPCL|CLOCAL;
+ /* set control chars */
+ tty.c_cc[VINTR] = 3; /* C-c */
+ tty.c_cc[VQUIT] = 28; /* C-\ */
+ tty.c_cc[VERASE] = 127; /* C-? */
+ tty.c_cc[VKILL] = 21; /* C-u */
+ tty.c_cc[VEOF] = 4; /* C-d */
+ tty.c_cc[VSTART] = 17; /* C-q */
+ tty.c_cc[VSTOP] = 19; /* C-s */
+ tty.c_cc[VSUSP] = 26; /* C-z */
- /* input modes */
- tty.c_iflag = IGNPAR|ICRNL|IXON|IXOFF|IXANY;
+ /* use line discipline 0 */
+ tty.c_line = 0;
- /* use line dicipline 0 */
- tty.c_line = 0;
+ /* Make it be sane */
+ tty.c_cflag &= CBAUD | CBAUDEX | CSIZE | CSTOPB | PARENB | PARODD;
+ tty.c_cflag |= CREAD | HUPCL | CLOCAL;
- /* output modes */
- tty.c_oflag = OPOST|ONLCR;
+ /* input modes */
+ tty.c_iflag = ICRNL | IXON | IXOFF;
- /* local modes */
- tty.c_lflag = ISIG|ICANON|ECHO|ECHOE|ECHOK|ECHOCTL|ECHOPRT|ECHOKE|IEXTEN;
+ /* output modes */
+ tty.c_oflag = OPOST | ONLCR;
- /* control chars */
- memcpy(tty.c_cc, control_characters, sizeof(control_characters));
+ /* local modes */
+ tty.c_lflag =
+ ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHOCTL | ECHOKE | IEXTEN;
- tcsetattr(fd, TCSANOW, &tty);
+ tcsetattr_stdin_TCSANOW(&tty);
}
-/* How much memory does this machine have? */
-static int mem_total()
+/* Open the new terminal device.
+ * NB: careful, we can be called after vfork! */
+static void open_stdio_to_tty(const char* tty_name, int exit_on_failure)
{
- char s[80];
- char *p = "/proc/meminfo";
- FILE *f;
- const char pattern[] = "MemTotal:";
-
- if ((f = fopen(p, "r")) < 0) {
- message(LOG, "Error opening %s: %s\n", p, strerror( errno));
- return -1;
- }
- while (NULL != fgets(s, 79, f)) {
- p = strstr(s, pattern);
- if (NULL != p) {
- fclose(f);
- return (atoi(p + strlen(pattern)));
+ /* empty tty_name means "use init's tty", else... */
+ if (tty_name[0]) {
+ int fd;
+ close(STDIN_FILENO);
+ /* fd can be only < 0 or 0: */
+ fd = device_open(tty_name, O_RDWR);
+ if (fd) {
+ message(L_LOG | L_CONSOLE, "can't open %s: %s",
+ tty_name, strerror(errno));
+ if (exit_on_failure)
+ _exit(EXIT_FAILURE);
+ if (DEBUG_INIT)
+ _exit(2);
+ /* NB: we don't reach this if we were called after vfork.
+ * Thus halt_reboot_pwoff() itself need not be vfork-safe. */
+ halt_reboot_pwoff(SIGUSR1); /* halt the system */
+ }
+ dup2(STDIN_FILENO, STDOUT_FILENO);
+ dup2(STDIN_FILENO, STDERR_FILENO);
}
- }
- return -1;
+ set_sane_term();
}
-static void console_init()
+/* Wrapper around exec:
+ * Takes string (max COMMAND_SIZE chars).
+ * If chars like '>' detected, execs '[-]/bin/sh -c "exec ......."'.
+ * Otherwise splits words on whitespace, deals with leading dash,
+ * and uses plain exec().
+ * NB: careful, we can be called after vfork!
+ */
+static void init_exec(const char *command)
{
- int fd;
- int tried_devcons = 0;
- int tried_vtprimary = 0;
- struct serial_struct sr;
- char *s;
-
- if ((s = getenv("CONSOLE")) != NULL) {
- console = s;
- }
-#if #cpu(sparc)
- /* sparc kernel supports console=tty[ab] parameter which is also
- * passed to init, so catch it here */
- else if ((s = getenv("console")) != NULL) {
- /* remap tty[ab] to /dev/ttyS[01] */
- if (strcmp( s, "ttya" )==0)
- console = SERIAL_CON0;
- else if (strcmp( s, "ttyb" )==0)
- console = SERIAL_CON1;
- }
-#endif
- else {
- struct vt_stat vt;
- static char the_console[13];
-
- console = the_console;
- /* 2.2 kernels: identify the real console backend and try to use it */
- if (ioctl(0,TIOCGSERIAL,&sr) == 0) {
- /* this is a serial console */
- snprintf( the_console, sizeof the_console, "/dev/ttyS%d", sr.line );
- }
- else if (ioctl(0, VT_GETSTATE, &vt) == 0) {
- /* this is linux virtual tty */
- snprintf( the_console, sizeof the_console, "/dev/tty%d", vt.v_active );
+ char *cmd[COMMAND_SIZE / 2];
+ char buf[COMMAND_SIZE + 6]; /* COMMAND_SIZE+strlen("exec ")+1 */
+ int dash = (command[0] == '-' /* maybe? && command[1] == '/' */);
+
+ /* See if any special /bin/sh requiring characters are present */
+ if (strpbrk(command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) {
+ strcpy(buf, "exec ");
+ strcpy(buf + 5, command + dash); /* excluding "-" */
+ /* NB: LIBBB_DEFAULT_LOGIN_SHELL define has leading dash */
+ cmd[0] = (char*)(LIBBB_DEFAULT_LOGIN_SHELL + !dash);
+ cmd[1] = (char*)"-c";
+ cmd[2] = buf;
+ cmd[3] = NULL;
} else {
- console = VT_CONSOLE;
- tried_devcons++;
+ /* Convert command (char*) into cmd (char**, one word per string) */
+ char *word, *next;
+ int i = 0;
+ next = strcpy(buf, command); /* including "-" */
+ while ((word = strsep(&next, " \t")) != NULL) {
+ if (*word != '\0') { /* not two spaces/tabs together? */
+ cmd[i] = word;
+ i++;
+ }
+ }
+ cmd[i] = NULL;
}
- }
-
- while ((fd = open(console, O_RDONLY | O_NONBLOCK)) < 0) {
- /* Can't open selected console -- try /dev/console */
- if (!tried_devcons) {
- tried_devcons++;
- console = VT_CONSOLE;
- continue;
+ /* If we saw leading "-", it is interactive shell.
+ * Try harder to give it a controlling tty.
+ * And skip "-" in actual exec call. */
+ if (dash) {
+ /* _Attempt_ to make stdin a controlling tty. */
+ if (ENABLE_FEATURE_INIT_SCTTY)
+ ioctl(STDIN_FILENO, TIOCSCTTY, 0 /*only try, don't steal*/);
}
- /* Can't open selected console -- try vt1 */
- if (!tried_vtprimary) {
- tried_vtprimary++;
- console = VT_PRIMARY;
- continue;
+ BB_EXECVP(cmd[0] + dash, cmd);
+ message(L_LOG | L_CONSOLE, "cannot run '%s': %s", cmd[0], strerror(errno));
+ /* returns if execvp fails */
+}
+
+/* Used only by run_actions */
+static pid_t run(const struct init_action *a)
+{
+ pid_t pid;
+ sigset_t nmask, omask;
+
+ /* Block sigchild while forking (why?) */
+ sigemptyset(&nmask);
+ sigaddset(&nmask, SIGCHLD);
+ sigprocmask(SIG_BLOCK, &nmask, &omask);
+ if (BB_MMU && (a->action_type & ASKFIRST))
+ pid = fork();
+ else
+ pid = vfork();
+ sigprocmask(SIG_SETMASK, &omask, NULL);
+
+ if (pid < 0)
+ message(L_LOG | L_CONSOLE, "can't fork");
+ if (pid)
+ return pid;
+
+ /* Child */
+
+ /* Reset signal handlers that were set by the parent process */
+ bb_signals(0
+ + (1 << SIGUSR1)
+ + (1 << SIGUSR2)
+ + (1 << SIGINT)
+ + (1 << SIGTERM)
+ + (1 << SIGHUP)
+ + (1 << SIGQUIT)
+ + (1 << SIGCONT)
+ + (1 << SIGSTOP)
+ + (1 << SIGTSTP)
+ , SIG_DFL);
+
+ /* Create a new session and make ourself the process
+ * group leader */
+ setsid();
+
+ /* Open the new terminal device */
+ open_stdio_to_tty(a->terminal, 1 /* - exit if open fails */);
+
+// NB: do not enable unless you change vfork to fork above
+#ifdef BUT_RUN_ACTIONS_ALREADY_DOES_WAITING
+ /* If the init Action requires us to wait, then force the
+ * supplied terminal to be the controlling tty. */
+ if (a->action_type & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
+ /* Now fork off another process to just hang around */
+ pid = fork();
+ if (pid < 0) {
+ message(L_LOG | L_CONSOLE, "can't fork");
+ _exit(EXIT_FAILURE);
+ }
+
+ if (pid > 0) {
+ /* Parent - wait till the child is done */
+ bb_signals(0
+ + (1 << SIGINT)
+ + (1 << SIGTSTP)
+ + (1 << SIGQUIT)
+ , SIG_IGN);
+ signal(SIGCHLD, SIG_DFL);
+
+ waitfor(pid);
+ /* See if stealing the controlling tty back is necessary */
+ if (tcgetpgrp(0) != getpid())
+ _exit(EXIT_SUCCESS);
+
+ /* Use a temporary process to steal the controlling tty. */
+ pid = fork();
+ if (pid < 0) {
+ message(L_LOG | L_CONSOLE, "can't fork");
+ _exit(EXIT_FAILURE);
+ }
+ if (pid == 0) {
+ setsid();
+ ioctl(0, TIOCSCTTY, 1);
+ _exit(EXIT_SUCCESS);
+ }
+ waitfor(pid);
+ _exit(EXIT_SUCCESS);
+ }
+ /* Child - fall though to actually execute things */
}
- break;
- }
- if (fd < 0)
- /* Perhaps we should panic here? */
- console = "/dev/null";
- else {
- /* check for serial console and disable logging to tty3 & running a
- * shell to tty2 */
- if (ioctl(0,TIOCGSERIAL,&sr) == 0) {
- log = NULL;
- second_console = NULL;
+#endif
+
+ /* NB: on NOMMU we can't wait for input in child, so
+ * "askfirst" will work the same as "respawn". */
+ if (BB_MMU && (a->action_type & ASKFIRST)) {
+ static const char press_enter[] ALIGN1 =
+#ifdef CUSTOMIZED_BANNER
+#include CUSTOMIZED_BANNER
+#endif
+ "\nPlease press Enter to activate this console. ";
+ char c;
+ /*
+ * Save memory by not exec-ing anything large (like a shell)
+ * before the user wants it. This is critical if swap is not
+ * enabled and the system has low memory. Generally this will
+ * be run on the second virtual console, and the first will
+ * be allowed to start a shell or whatever an init script
+ * specifies.
+ */
+ messageD(L_LOG, "waiting for enter to start '%s'"
+ "(pid %d, tty '%s')\n",
+ a->command, getpid(), a->terminal);
+ full_write(STDOUT_FILENO, press_enter, sizeof(press_enter) - 1);
+ while (safe_read(STDIN_FILENO, &c, 1) == 1 && c != '\n')
+ continue;
+ }
+
+ if (ENABLE_FEATURE_INIT_COREDUMPS) {
+ struct stat sb;
+ if (stat(CORE_ENABLE_FLAG_FILE, &sb) == 0) {
+ struct rlimit limit;
+ limit.rlim_cur = RLIM_INFINITY;
+ limit.rlim_max = RLIM_INFINITY;
+ setrlimit(RLIMIT_CORE, &limit);
+ }
+ }
+
+ /* Log the process name and args */
+ message(L_LOG, "starting pid %d, tty '%s': '%s'",
+ getpid(), a->terminal, a->command);
+
+ /* Now run it. The new program will take over this PID,
+ * so nothing further in init.c should be run. */
+ init_exec(a->command);
+ /* We're still here? Some error happened. */
+ _exit(-1);
+}
+
+static void delete_init_action(struct init_action *action)
+{
+ struct init_action *a, *b = NULL;
+
+ for (a = init_action_list; a; b = a, a = a->next) {
+ if (a == action) {
+ if (b == NULL) {
+ init_action_list = a->next;
+ } else {
+ b->next = a->next;
+ }
+ free(a);
+ break;
+ }
}
- close(fd);
- }
- message(LOG, "console=%s\n", console );
}
-static int waitfor(int pid)
+/* Run all commands of a particular type */
+static void run_actions(int action_type)
{
- int status, wpid;
-
- message(LOG, "Waiting for process %d.\n", pid);
- while ((wpid = wait(&status)) != pid) {
- if (wpid > 0)
- message(LOG, "pid %d exited, status=0x%x.\n", wpid, status);
- }
- return wpid;
+ struct init_action *a, *tmp;
+
+ for (a = init_action_list; a; a = tmp) {
+ tmp = a->next;
+ if (a->action_type & action_type) {
+ // Pointless: run() will error out if open of device fails.
+ ///* a->terminal of "" means "init's console" */
+ //if (a->terminal[0] && access(a->terminal, R_OK | W_OK)) {
+ // //message(L_LOG | L_CONSOLE, "Device %s cannot be opened in RW mode", a->terminal /*, strerror(errno)*/);
+ // delete_init_action(a);
+ //} else
+ if (a->action_type & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
+ waitfor(run(a));
+ delete_init_action(a);
+ } else if (a->action_type & ONCE) {
+ run(a);
+ delete_init_action(a);
+ } else if (a->action_type & (RESPAWN | ASKFIRST)) {
+ /* Only run stuff with pid==0. If they have
+ * a pid, that means it is still running */
+ if (a->pid == 0) {
+ a->pid = run(a);
+ }
+ }
+ }
+ }
}
+static void init_reboot(unsigned long magic)
+{
+ pid_t pid;
+ /* We have to fork here, since the kernel calls do_exit(EXIT_SUCCESS) in
+ * linux/kernel/sys.c, which can cause the machine to panic when
+ * the init process is killed.... */
+ pid = vfork();
+ if (pid == 0) { /* child */
+ reboot(magic);
+ _exit(EXIT_SUCCESS);
+ }
+ waitfor(pid);
+}
-static pid_t run(const char * const* command,
- char *terminal, int get_enter)
+static void kill_all_processes(void)
{
- int fd;
- pid_t pid;
- const char * const* cmd = command+1;
- static const char press_enter[] =
- "\nPlease press Enter to activate this console. ";
-
- if ((pid = fork()) == 0) {
- /* Clean up */
- close(0);
- close(1);
- close(2);
- setsid();
+ /* run everything to be run at "shutdown". This is done _prior_
+ * to killing everything, in case people wish to use scripts to
+ * shut things down gracefully... */
+ run_actions(SHUTDOWN);
- /* Reset signal handlers set for parent process */
- signal(SIGUSR1, SIG_DFL);
- signal(SIGUSR2, SIG_DFL);
- signal(SIGINT, SIG_DFL);
- signal(SIGTERM, SIG_DFL);
+ /* first disable all our signals */
+ sigprocmask_allsigs(SIG_BLOCK);
- if ((fd = device_open(terminal, O_RDWR)) < 0) {
- message(LOG, "Bummer, can't open %s\r\n", terminal);
- exit(-1);
- }
- dup(fd);
- dup(fd);
- tcsetpgrp(0, getpgrp());
- set_term(0);
-
- if (get_enter==TRUE) {
- /*
- * Save memory by not exec-ing anything large (like a shell)
- * before the user wants it. This is critical if swap is not
- * enabled and the system has low memory. Generally this will
- * be run on the second virtual console, and the first will
- * be allowed to start a shell or whatever an init script
- * specifies.
- */
- char c;
- message(LOG, "Waiting for enter to start '%s' (pid %d, console %s)\r\n",
- *cmd, getpid(), terminal );
- write(1, press_enter, sizeof(press_enter) - 1);
- read(0, &c, 1);
+ message(L_CONSOLE | L_LOG, "The system is going down NOW!");
+
+ /* Allow Ctrl-Alt-Del to reboot system. */
+ init_reboot(RB_ENABLE_CAD);
+
+ /* Send signals to every process _except_ pid 1 */
+ message(L_CONSOLE | L_LOG, "Sending SIG%s to all processes", "TERM");
+ kill(-1, SIGTERM);
+ sync();
+ sleep(1);
+
+ message(L_CONSOLE | L_LOG, "Sending SIG%s to all processes", "KILL");
+ kill(-1, SIGKILL);
+ sync();
+ sleep(1);
+}
+
+static void halt_reboot_pwoff(int sig)
+{
+ const char *m = "halt";
+ int rb;
+
+ kill_all_processes();
+
+ rb = RB_HALT_SYSTEM;
+ if (sig == SIGTERM) {
+ m = "reboot";
+ rb = RB_AUTOBOOT;
+ } else if (sig == SIGUSR2) {
+ m = "poweroff";
+ rb = RB_POWER_OFF;
}
+ message(L_CONSOLE | L_LOG, "Requesting system %s", m);
+ /* allow time for last message to reach serial console */
+ sleep(2);
+ init_reboot(rb);
+ loop_forever();
+}
- /* Log the process name and args */
- message(LOG, "Starting pid %d, console %s: '", getpid(), terminal);
- while ( *cmd) message(LOG, "%s ", *cmd++);
- message(LOG, "'\r\n");
-
- /* Now run it. The new program will take over this PID,
- * so nothing further in init.c should be run. */
- execvp(*command, (char**)command+1);
+/* Handler for QUIT - exec "restart" action,
+ * else (no such action defined) do nothing */
+static void exec_restart_action(int sig UNUSED_PARAM)
+{
+ struct init_action *a;
+
+ for (a = init_action_list; a; a = a->next) {
+ if (a->action_type & RESTART) {
+ kill_all_processes();
- message(LOG, "Bummer, could not run '%s'\n", command);
- exit(-1);
- }
- return pid;
+ /* unblock all signals (blocked in kill_all_processes()) */
+ sigprocmask_allsigs(SIG_UNBLOCK);
+
+ /* Open the new terminal device */
+ open_stdio_to_tty(a->terminal, 0 /* - halt if open fails */);
+
+ messageD(L_CONSOLE | L_LOG, "Trying to re-exec %s", a->command);
+ init_exec(a->command);
+ sleep(2);
+ init_reboot(RB_HALT_SYSTEM);
+ loop_forever();
+ }
+ }
}
-/* Make sure there is enough memory to do something useful. *
- * Calls swapon if needed so be sure /proc is mounted. */
-static void check_memory()
+static void ctrlaltdel_signal(int sig UNUSED_PARAM)
{
- struct stat statbuf;
- const char* const swap_on_cmd[] =
- { "/bin/swapon", "swapon", "-a", 0};
-
- if (mem_total() > 3500)
- return;
-
- if (stat("/etc/fstab", &statbuf) == 0) {
- /* Try to turn on swap */
- waitfor(run(swap_on_cmd, log, FALSE));
- if (mem_total() < 3500)
- goto goodnight;
- } else
- goto goodnight;
- return;
-
-goodnight:
- message(CONSOLE, "Sorry, your computer does not have enough memory.\r\n");
- while (1) sleep(1);
+ run_actions(CTRLALTDEL);
}
-static void shutdown_system(void)
+/* The SIGCONT handler is set to record_signo().
+ * It just sets bb_got_signal = SIGCONT. */
+
+/* The SIGSTOP & SIGTSTP handler */
+static void stop_handler(int sig UNUSED_PARAM)
{
- const char* const swap_off_cmd[] = { "swapoff", "swapoff", "-a", 0};
- const char* const umount_cmd[] = { "umount", "umount", "-a", "-n", 0};
+ int saved_errno = errno;
-#ifndef DEBUG_INIT
- /* Allow Ctrl-Alt-Del to reboot system. */
- reboot(RB_ENABLE_CAD);
-#endif
- message(CONSOLE, "The system is going down NOW !!\r\n");
- sync();
- /* Send signals to every process _except_ pid 1 */
- message(CONSOLE, "Sending SIGHUP to all processes.\r\n");
-#ifndef DEBUG_INIT
- kill(-1, SIGHUP);
-#endif
- sleep(2);
- sync();
- message(CONSOLE, "Sending SIGKILL to all processes.\r\n");
-#ifndef DEBUG_INIT
- kill(-1, SIGKILL);
-#endif
- sleep(1);
- waitfor(run( swap_off_cmd, console, FALSE));
- waitfor(run( umount_cmd, console, FALSE));
- sync();
- if (kernel_version > 0 && kernel_version <= 2 * 65536 + 2 * 256 + 11) {
- /* bdflush, kupdate not needed for kernels >2.2.11 */
- message(CONSOLE, "Flushing buffers.\r\n");
- bdflush(1, 0);
- sync();
- }
+ bb_got_signal = 0;
+ while (bb_got_signal == 0)
+ pause();
+
+ errno = saved_errno;
}
-static void halt_signal(int sig)
+static void new_init_action(uint8_t action_type, const char *command, const char *cons)
{
- shutdown_system();
- message(CONSOLE,
- "The system is halted. Press CTRL-ALT-DEL or turn off power\r\n");
- sync();
-#ifndef DEBUG_INIT
- reboot(RB_HALT_SYSTEM);
- //reboot(RB_POWER_OFF);
-#endif
- exit(0);
+ struct init_action *a, *last;
+
+// Why?
+// if (strcmp(cons, bb_dev_null) == 0 && (action & ASKFIRST))
+// return;
+
+ /* Append to the end of the list */
+ for (a = last = init_action_list; a; a = a->next) {
+ /* don't enter action if it's already in the list,
+ * but do overwrite existing actions */
+ if ((strcmp(a->command, command) == 0)
+ && (strcmp(a->terminal, cons) == 0)
+ ) {
+ a->action_type = action_type;
+ return;
+ }
+ last = a;
+ }
+
+ a = xzalloc(sizeof(*a));
+ if (last) {
+ last->next = a;
+ } else {
+ init_action_list = a;
+ }
+ a->action_type = action_type;
+ safe_strncpy(a->command, command, sizeof(a->command));
+ safe_strncpy(a->terminal, cons, sizeof(a->terminal));
+ messageD(L_LOG | L_CONSOLE, "command='%s' action=%d tty='%s'\n",
+ a->command, a->action_type, a->terminal);
}
-static void reboot_signal(int sig)
+/* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
+ * then parse_inittab() simply adds in some default
+ * actions(i.e., runs INIT_SCRIPT and then starts a pair
+ * of "askfirst" shells). If CONFIG_FEATURE_USE_INITTAB
+ * _is_ defined, but /etc/inittab is missing, this
+ * results in the same set of default behaviors.
+ */
+static void parse_inittab(void)
{
- shutdown_system();
- message(CONSOLE, "Please stand by while rebooting the system.\r\n");
- sync();
-#ifndef DEBUG_INIT
- reboot(RB_AUTOBOOT);
-#endif
- exit(0);
+ char *token[4];
+ /* order must correspond to SYSINIT..RESTART constants */
+ static const char actions[] ALIGN1 =
+ "sysinit\0""respawn\0""askfirst\0""wait\0""once\0"
+ "ctrlaltdel\0""shutdown\0""restart\0";
+
+ parser_t *parser = config_open2(INITTAB, fopen_for_read);
+ /* No inittab file -- set up some default behavior */
+ if (parser == NULL) {
+ /* Reboot on Ctrl-Alt-Del */
+ new_init_action(CTRLALTDEL, "reboot", "");
+ /* Umount all filesystems on halt/reboot */
+ new_init_action(SHUTDOWN, "umount -a -r", "");
+ /* Swapoff on halt/reboot */
+ if (ENABLE_SWAPONOFF)
+ new_init_action(SHUTDOWN, "swapoff -a", "");
+ /* Prepare to restart init when a QUIT is received */
+ new_init_action(RESTART, "init", "");
+ /* Askfirst shell on tty1-4 */
+ new_init_action(ASKFIRST, bb_default_login_shell, "");
+//TODO: VC_1 instead of ""? "" is console -> ctty problems -> angry users
+ new_init_action(ASKFIRST, bb_default_login_shell, VC_2);
+ new_init_action(ASKFIRST, bb_default_login_shell, VC_3);
+ new_init_action(ASKFIRST, bb_default_login_shell, VC_4);
+ /* sysinit */
+ new_init_action(SYSINIT, INIT_SCRIPT, "");
+ return;
+ }
+ /* optional_tty:ignored_runlevel:action:command
+ * Delims are not to be collapsed and need exactly 4 tokens
+ */
+ while (config_read(parser, token, 4, 0, "#:",
+ PARSE_NORMAL & ~(PARSE_TRIM | PARSE_COLLAPSE))) {
+ int action;
+ char *tty = token[0];
+
+ if (!token[3]) /* less than 4 tokens */
+ goto bad_entry;
+ action = index_in_strings(actions, token[2]);
+ if (action < 0 || !token[3][0]) /* token[3]: command */
+ goto bad_entry;
+ /* turn .*TTY -> /dev/TTY */
+ if (tty[0]) {
+ if (strncmp(tty, "/dev/", 5) == 0)
+ tty += 5;
+ tty = concat_path_file("/dev/", tty);
+ }
+ new_init_action(1 << action, token[3], tty);
+ if (tty[0])
+ free(tty);
+ continue;
+ bad_entry:
+ message(L_LOG | L_CONSOLE, "Bad inittab entry at line %d",
+ parser->lineno);
+ }
+ config_close(parser);
}
-extern int init_main(int argc, char **argv)
+#if ENABLE_FEATURE_USE_INITTAB
+static void reload_signal(int sig UNUSED_PARAM)
{
- int run_rc = TRUE;
- int wait_for_enter = TRUE;
- pid_t pid1 = 0;
- pid_t pid2 = 0;
- struct stat statbuf;
- const char* const init_commands[] = { INITSCRIPT, INITSCRIPT, 0};
- const char* const shell_commands[] = { SHELL, "-" SHELL, 0};
- const char* const* tty0_commands = shell_commands;
- const char* const* tty1_commands = shell_commands;
-#ifdef DEBUG_INIT
- char *hello_msg_format =
- "init(%d) started: BusyBox v%s (%s) multi-call binary\r\n";
-#else
- char *hello_msg_format =
- "init started: BusyBox v%s (%s) multi-call binary\r\n";
-#endif
+ struct init_action *a, *tmp;
-
- /* Check if we are supposed to be in single user mode */
- if ( argc > 1 && (!strcmp(argv[1], "single") ||
- !strcmp(argv[1], "-s") || !strcmp(argv[1], "1"))) {
- run_rc = FALSE;
- }
-
-
- /* Set up sig handlers -- be sure to
- * clear all of these in run() */
- signal(SIGUSR1, halt_signal);
- signal(SIGUSR2, reboot_signal);
- signal(SIGINT, reboot_signal);
- signal(SIGTERM, reboot_signal);
-
- /* Turn off rebooting via CTL-ALT-DEL -- we get a
- * SIGINT on CAD so we can shut things down gracefully... */
-#ifndef DEBUG_INIT
- reboot(RB_DISABLE_CAD);
-#endif
-
- /* Figure out where the default console should be */
- console_init();
-
- /* Close whatever files are open, and reset the console. */
- close(0);
- close(1);
- close(2);
- set_term(0);
- setsid();
-
- /* Make sure PATH is set to something sane */
- putenv(PATH_DEFAULT);
-
-
- /* Hello world */
-#ifndef DEBUG_INIT
- message(CONSOLE|LOG, hello_msg_format, BB_VER, BB_BT);
-#else
- message(CONSOLE|LOG, hello_msg_format, getpid(), BB_VER, BB_BT);
+ message(L_LOG, "reloading /etc/inittab");
+
+ /* disable old entrys */
+ for (a = init_action_list; a; a = a->next) {
+ a->action_type = ONCE;
+ }
+
+ parse_inittab();
+
+ if (ENABLE_FEATURE_KILL_REMOVED) {
+ /* Be nice and send SIGTERM first */
+ for (a = init_action_list; a; a = a->next) {
+ pid_t pid = a->pid;
+ if ((a->action_type & ONCE) && pid != 0) {
+ kill(pid, SIGTERM);
+ }
+ }
+#if CONFIG_FEATURE_KILL_DELAY
+ /* NB: parent will wait in NOMMU case */
+ if ((BB_MMU ? fork() : vfork()) == 0) { /* child */
+ sleep(CONFIG_FEATURE_KILL_DELAY);
+ for (a = init_action_list; a; a = a->next) {
+ pid_t pid = a->pid;
+ if ((a->action_type & ONCE) && pid != 0) {
+ kill(pid, SIGKILL);
+ }
+ }
+ _exit(EXIT_SUCCESS);
+ }
#endif
+ }
-
- /* Mount /proc */
- if (mount ("proc", "/proc", "proc", 0, 0) == 0) {
- message(CONSOLE|LOG, "Mounting /proc: done.\n");
- kernel_version = get_kernel_revision();
- } else
- message(CONSOLE|LOG, "Mounting /proc: failed!\n");
+ /* remove unused entrys */
+ for (a = init_action_list; a; a = tmp) {
+ tmp = a->next;
+ if ((a->action_type & (ONCE | SYSINIT | WAIT)) && a->pid == 0) {
+ delete_init_action(a);
+ }
+ }
+ run_actions(RESPAWN | ASKFIRST);
+}
+#endif
- /* Make sure there is enough memory to do something useful. */
- check_memory();
+int init_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int init_main(int argc UNUSED_PARAM, char **argv)
+{
+ struct init_action *a;
+ pid_t wpid;
+ die_sleep = 30 * 24*60*60; /* if xmalloc will ever die... */
- /* Make sure an init script exists before trying to run it */
- if (run_rc == TRUE && stat(INITSCRIPT, &statbuf)==0) {
- wait_for_enter = FALSE;
- tty0_commands = init_commands;
- }
+ if (argv[1] && !strcmp(argv[1], "-q")) {
+ return kill(1, SIGHUP);
+ }
+ if (!DEBUG_INIT) {
+ /* Expect to be invoked as init with PID=1 or be invoked as linuxrc */
+ if (getpid() != 1
+ && (!ENABLE_FEATURE_INITRD || !strstr(applet_name, "linuxrc"))
+ ) {
+ bb_show_usage();
+ }
+ /* Set up sig handlers -- be sure to
+ * clear all of these in run() */
+ signal(SIGQUIT, exec_restart_action);
+ bb_signals(0
+ + (1 << SIGUSR1) /* halt */
+ + (1 << SIGUSR2) /* poweroff */
+ + (1 << SIGTERM) /* reboot */
+ , halt_reboot_pwoff);
+ signal(SIGINT, ctrlaltdel_signal);
+ signal(SIGCONT, record_signo);
+ bb_signals(0
+ + (1 << SIGSTOP)
+ + (1 << SIGTSTP)
+ , stop_handler);
+
+ /* Turn off rebooting via CTL-ALT-DEL -- we get a
+ * SIGINT on CAD so we can shut things down gracefully... */
+ init_reboot(RB_DISABLE_CAD);
+ }
- /* Ok, now launch the rc script and/or prepare to
- * start up some VTs if somebody hits enter...
- */
- for (;;) {
- pid_t wpid;
- int status;
+ /* Figure out where the default console should be */
+ console_init();
+ set_sane_term();
+ xchdir("/");
+ setsid();
- if (pid1 == 0 && tty0_commands) {
- pid1 = run(tty0_commands, console, wait_for_enter);
+ /* Make sure environs is set to something sane */
+ putenv((char *) "HOME=/");
+ putenv((char *) bb_PATH_root_path);
+ putenv((char *) "SHELL=/bin/sh");
+ putenv((char *) "USER=root"); /* needed? why? */
+
+ if (argv[1])
+ xsetenv("RUNLEVEL", argv[1]);
+
+ /* Hello world */
+ message(MAYBE_CONSOLE | L_LOG, "init started: %s", bb_banner);
+
+ /* Make sure there is enough memory to do something useful. */
+ if (ENABLE_SWAPONOFF) {
+ struct sysinfo info;
+
+ if (!sysinfo(&info) &&
+ (info.mem_unit ? : 1) * (long long)info.totalram < 1024*1024)
+ {
+ message(L_CONSOLE, "Low memory, forcing swapon");
+ /* swapon -a requires /proc typically */
+ new_init_action(SYSINIT, "mount -t proc proc /proc", "");
+ /* Try to turn on swap */
+ new_init_action(SYSINIT, "swapon -a", "");
+ run_actions(SYSINIT); /* wait and removing */
+ }
}
- if (pid2 == 0 && tty1_commands && second_console) {
- pid2 = run(tty1_commands, second_console, TRUE);
+
+ /* Check if we are supposed to be in single user mode */
+ if (argv[1]
+ && (!strcmp(argv[1], "single") || !strcmp(argv[1], "-s") || LONE_CHAR(argv[1], '1'))
+ ) {
+ /* ??? shouldn't we set RUNLEVEL="b" here? */
+ /* Start a shell on console */
+ new_init_action(RESPAWN, bb_default_login_shell, "");
+ } else {
+ /* Not in single user mode -- see what inittab says */
+
+ /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
+ * then parse_inittab() simply adds in some default
+ * actions(i.e., runs INIT_SCRIPT and then starts a pair
+ * of "askfirst" shells */
+ parse_inittab();
}
- wpid = wait(&status);
- if (wpid > 0 ) {
- message(LOG, "pid %d exited, status=%x.\n", wpid, status);
+
+#if ENABLE_SELINUX
+ if (getenv("SELINUX_INIT") == NULL) {
+ int enforce = 0;
+
+ putenv((char*)"SELINUX_INIT=YES");
+ if (selinux_init_load_policy(&enforce) == 0) {
+ BB_EXECVP(argv[0], argv);
+ } else if (enforce > 0) {
+ /* SELinux in enforcing mode but load_policy failed */
+ message(L_CONSOLE, "cannot load SELinux Policy. "
+ "Machine is in enforcing mode. Halting now.");
+ exit(EXIT_FAILURE);
+ }
}
- /* Don't respawn init script if it exits */
- if (wpid == pid1) {
- if (run_rc == FALSE) {
- pid1 = 0;
- }
-#if 0
-/* Turn this on to start a shell on the console if the init script exits.... */
- else {
- run_rc=FALSE;
- wait_for_enter=TRUE;
- tty0_commands=shell_commands;
- }
+#endif /* CONFIG_SELINUX */
+
+ /* Make the command line just say "init" - thats all, nothing else */
+ strncpy(argv[0], "init", strlen(argv[0]));
+ /* Wipe argv[1]-argv[N] so they don't clutter the ps listing */
+ while (*++argv)
+ memset(*argv, 0, strlen(*argv));
+
+ /* Now run everything that needs to be run */
+
+ /* First run the sysinit command */
+ run_actions(SYSINIT);
+
+ /* Next run anything that wants to block */
+ run_actions(WAIT);
+
+ /* Next run anything to be run only once */
+ run_actions(ONCE);
+
+ /* Redefine SIGHUP to reread /etc/inittab */
+#if ENABLE_FEATURE_USE_INITTAB
+ signal(SIGHUP, reload_signal);
+#else
+ signal(SIGHUP, SIG_IGN);
#endif
+
+ /* Now run the looping stuff for the rest of forever */
+ while (1) {
+ /* run the respawn/askfirst stuff */
+ run_actions(RESPAWN | ASKFIRST);
+
+ /* Don't consume all CPU time -- sleep a bit */
+ sleep(1);
+
+ /* Wait for any child process to exit */
+ wpid = wait(NULL);
+ while (wpid > 0) {
+ /* Find out who died and clean up their corpse */
+ for (a = init_action_list; a; a = a->next) {
+ if (a->pid == wpid) {
+ /* Set the pid to 0 so that the process gets
+ * restarted by run_actions() */
+ a->pid = 0;
+ message(L_LOG, "process '%s' (pid %d) exited. "
+ "Scheduling for restart.",
+ a->command, wpid);
+ }
+ }
+ /* see if anyone else is waiting to be reaped */
+ wpid = wait_any_nohang(NULL);
+ }
}
- if (wpid == pid2) {
- pid2 = 0;
- }
- sleep(1);
- }
}
projects / oweals / busybox.git / blobdiff