| /* |
| * Mini init implementation for busybox |
| * |
| * |
| * Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>. |
| * 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 |
| * |
| */ |
| |
| #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 <paths.h> |
| #include <sys/types.h> |
| #include <sys/fcntl.h> |
| #include <sys/wait.h> |
| #include <string.h> |
| #include <sys/mount.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> |
| #ifdef BB_SYSLOGD |
| #include <sys/syslog.h> |
| #endif |
| |
| #if ! defined BB_FEATURE_USE_PROCFS |
| #error Sorry, I depend on the /proc filesystem right now. |
| #endif |
| |
| |
| #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 GETTY "/sbin/getty" /* Default location of getty */ |
| #define SHELL "/bin/sh" /* Default shell */ |
| #define INITSCRIPT "/etc/init.d/rcS" /* Initscript. */ |
| |
| #define LOG 0x1 |
| #define CONSOLE 0x2 |
| static char *console = _PATH_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) |
| { |
| 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; |
| } |
| |
| /* print a message to the specified device: |
| * device may be bitwise-or'd from LOG | CONSOLE */ |
| void message(int device, char *fmt, ...) |
| { |
| int fd; |
| va_list arguments; |
| #ifdef BB_SYSLOGD |
| |
| /* Log the message to syslogd */ |
| if (device & LOG ) { |
| char msg[1024]; |
| va_start(arguments, fmt); |
| vsnprintf(msg, sizeof(msg), fmt, arguments); |
| va_end(arguments); |
| syslog(LOG_DAEMON|LOG_NOTICE, msg); |
| } |
| |
| #else |
| static int log_fd=-1; |
| |
| /* 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; |
| } |
| } |
| if ( (device & LOG) && (log_fd >= 0) ) { |
| va_start(arguments, fmt); |
| vdprintf(log_fd, fmt, arguments); |
| va_end(arguments); |
| } |
| #endif |
| |
| if (device & CONSOLE) { |
| /* Always send console messages to /dev/console so people will see them. */ |
| if ((fd = device_open(_PATH_CONSOLE, O_WRONLY|O_NOCTTY|O_NDELAY)) >= 0) { |
| va_start(arguments, fmt); |
| vdprintf(fd, fmt, arguments); |
| va_end(arguments); |
| close(fd); |
| } else { |
| fprintf(stderr, "Bummer, can't print: "); |
| va_start(arguments, fmt); |
| vfprintf(stderr, fmt, arguments); |
| fflush(stderr); |
| va_end(arguments); |
| } |
| } |
| } |
| |
| |
| /* Set terminal settings to reasonable defaults */ |
| void set_term( int fd) |
| { |
| struct termios tty; |
| #if 0 |
| static const char control_characters[] = { |
| '\003', '\034', '\177', '\030', '\004', '\0', |
| '\1', '\0', '\021', '\023', '\032', '\0', '\022', |
| '\017', '\027', '\026', '\0' |
| }; |
| #else |
| static const char control_characters[] = { |
| '\003', '\034', '\177', '\025', '\004', '\0', |
| '\1', '\0', '\021', '\023', '\032', '\0', '\022', |
| '\017', '\027', '\026', '\0' |
| }; |
| #endif |
| |
| tcgetattr(fd, &tty); |
| |
| /* set control chars */ |
| memcpy(tty.c_cc, control_characters, sizeof(control_characters)); |
| |
| /* use line dicipline 0 */ |
| tty.c_line = 0; |
| |
| /* Make it be sane */ |
| //tty.c_cflag &= CBAUD|CBAUDEX|CSIZE|CSTOPB|PARENB|PARODD; |
| //tty.c_cflag |= HUPCL|CLOCAL; |
| |
| /* input modes */ |
| tty.c_iflag = ICRNL|IXON|IXOFF; |
| |
| /* output modes */ |
| tty.c_oflag = OPOST|ONLCR; |
| |
| /* local modes */ |
| tty.c_lflag = ISIG|ICANON|ECHO|ECHOE|ECHOK|ECHOCTL|ECHOKE|IEXTEN; |
| |
| tcsetattr(fd, TCSANOW, &tty); |
| } |
| |
| /* How much memory does this machine have? */ |
| static int mem_total() |
| { |
| 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))); |
| } |
| } |
| return -1; |
| } |
| |
| static void console_init() |
| { |
| 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 ); |
| } else { |
| console = _PATH_CONSOLE; |
| tried_devcons++; |
| } |
| } |
| |
| while ((fd = open(console, O_RDONLY | O_NONBLOCK)) < 0) { |
| /* Can't open selected console -- try /dev/console */ |
| if (!tried_devcons) { |
| tried_devcons++; |
| console = _PATH_CONSOLE; |
| continue; |
| } |
| /* Can't open selected console -- try vt1 */ |
| if (!tried_vtprimary) { |
| tried_vtprimary++; |
| console = VT_PRIMARY; |
| continue; |
| } |
| 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) { |
| message(LOG|CONSOLE, "serial console detected. Disabling 2nd virtual terminal.\r\n", console ); |
| log = NULL; |
| second_console = NULL; |
| } |
| close(fd); |
| } |
| message(LOG, "console=%s\n", console ); |
| } |
| |
| static int waitfor(int pid) |
| { |
| 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; |
| } |
| |
| |
| static pid_t run(const char * const* command, |
| char *terminal, int get_enter) |
| { |
| 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(); |
| |
| /* Reset signal handlers set for parent process */ |
| signal(SIGUSR1, SIG_DFL); |
| signal(SIGUSR2, SIG_DFL); |
| signal(SIGINT, SIG_DFL); |
| signal(SIGTERM, SIG_DFL); |
| |
| 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); |
| } |
| |
| /* 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); |
| |
| message(LOG, "Bummer, could not run '%s'\n", command); |
| exit(-1); |
| } |
| return pid; |
| } |
| |
| /* Make sure there is enough memory to do something useful. * |
| * Calls swapon if needed so be sure /proc is mounted. */ |
| static void check_memory() |
| { |
| 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); |
| } |
| |
| static void shutdown_system(void) |
| { |
| const char* const swap_off_cmd[] = { "swapoff", "swapoff", "-a", 0}; |
| const char* const umount_cmd[] = { "umount", "umount", "-a", "-n", 0}; |
| |
| #ifndef DEBUG_INIT |
| /* Allow Ctrl-Alt-Del to reboot system. */ |
| reboot(RB_ENABLE_CAD); |
| #endif |
| message(CONSOLE, "\r\nThe 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); |
| message(CONSOLE, "Disabling swap.\r\n"); |
| waitfor(run( swap_off_cmd, console, FALSE)); |
| message(CONSOLE, "Unmounting filesystems.\r\n"); |
| 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(); |
| } |
| } |
| |
| static void halt_signal(int sig) |
| { |
| shutdown_system(); |
| message(CONSOLE, |
| "The system is halted. Press CTRL-ALT-DEL or turn off power\r\n"); |
| sync(); |
| #ifndef DEBUG_INIT |
| while (1) sleep(1); |
| reboot(RB_HALT_SYSTEM); |
| //reboot(RB_POWER_OFF); |
| #endif |
| exit(0); |
| } |
| |
| static void reboot_signal(int sig) |
| { |
| shutdown_system(); |
| message(CONSOLE, "Please stand by while rebooting the system.\r\n"); |
| sync(); |
| while (1) sleep(1); |
| #ifndef DEBUG_INIT |
| reboot(RB_AUTOBOOT); |
| #endif |
| exit(0); |
| } |
| |
| extern int init_main(int argc, char **argv) |
| { |
| int run_rc = FALSE; |
| int single = FALSE; |
| int wait_for_enter_tty1 = TRUE; |
| int wait_for_enter_tty2 = TRUE; |
| pid_t pid1 = 0; |
| pid_t pid2 = 0; |
| struct stat statbuf; |
| const char* const rc_script_command[] = { INITSCRIPT, INITSCRIPT, 0}; |
| const char* const getty1_command[] = { GETTY, GETTY, VT_PRIMARY, 0}; |
| const char* const getty2_command[] = { GETTY, GETTY, VT_SECONDARY, 0}; |
| const char* const shell_command[] = { SHELL, "-" SHELL, 0}; |
| const char* const* tty1_command = shell_command; |
| const char* const* tty2_command = shell_command; |
| #ifdef BB_INIT_CMD_IF_RC_SCRIPT_EXITS |
| const char* const rc_exit_command[] = { "BB_INIT_CMD_IF_RC_SCRIPT_EXITS", |
| "BB_INIT_CMD_IF_RC_SCRIPT_EXITS", 0 }; |
| #endif |
| |
| #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 |
| |
| |
| #ifndef DEBUG_INIT |
| /* Expect to be PID 1 iff we are run as init (not linuxrc) */ |
| if (getpid() != 1 && strstr(argv[0], "init")!=NULL ) { |
| usage( "init\n\nInit is the parent of all processes.\n\n" |
| "This version of init is designed to be run only by the kernel\n"); |
| } |
| #endif |
| |
| /* 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_STDPATH); |
| |
| |
| /* 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); |
| #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"); |
| |
| /* Make sure there is enough memory to do something useful. */ |
| check_memory(); |
| |
| /* 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"))) { |
| single = TRUE; |
| tty1_command = shell_command; |
| tty2_command = shell_command; |
| } |
| |
| /* Make sure an init script exists before trying to run it */ |
| if (single==FALSE && stat(INITSCRIPT, &statbuf)==0) { |
| run_rc = TRUE; |
| wait_for_enter_tty1 = FALSE; |
| tty1_command = rc_script_command; |
| } |
| |
| /* Make sure /sbin/getty exists before trying to run it */ |
| if (stat(GETTY, &statbuf)==0) { |
| char* where; |
| wait_for_enter_tty2 = FALSE; |
| where = strrchr( console, '/'); |
| if ( where != NULL) { |
| strcpy( (char*)getty2_command[2], where); |
| } |
| tty2_command = getty2_command; |
| /* Check on hooking a getty onto tty1 */ |
| if (run_rc == FALSE && single==FALSE) { |
| wait_for_enter_tty1 = FALSE; |
| where = strrchr( second_console, '/'); |
| if ( where != NULL) { |
| strcpy( (char*)getty1_command[2], where); |
| } |
| tty1_command = getty1_command; |
| } |
| } |
| |
| |
| /* Ok, now launch the tty1_command and tty2_command */ |
| for (;;) { |
| pid_t wpid; |
| int status; |
| |
| if (pid1 == 0 && tty1_command) { |
| pid1 = run(tty1_command, console, wait_for_enter_tty1); |
| } |
| #ifdef BB_FEATURE_INIT_SECOND_CONSOLE |
| if (pid2 == 0 && tty2_command && second_console) { |
| pid2 = run(tty2_command, second_console, wait_for_enter_tty2); |
| } |
| #endif |
| wpid = wait(&status); |
| if (wpid > 0 ) { |
| message(LOG, "pid %d exited, status=%x.\n", wpid, status); |
| } |
| /* Don't respawn init script if it exits */ |
| if (wpid == pid1) { |
| if (run_rc == FALSE) { |
| pid1 = 0; |
| } |
| #ifdef BB_INIT_CMD_IF_RC_SCRIPT_EXITS |
| else { |
| pid1 = 0; |
| run_rc=FALSE; |
| wait_for_enter_tty1=TRUE; |
| tty1_command=rc_exit_command; |
| } |
| #endif |
| } |
| #ifdef BB_FEATURE_INIT_SECOND_CONSOLE |
| if (wpid == pid2) { |
| pid2 = 0; |
| } |
| #endif |
| sleep(1); |
| } |
| } |