X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=init%2Finit.c;h=f7eb8f34ba3510d1b463e8acc1b1d18a97795e07;hb=ce34cccf28d3b46defbc048f8748d0c870ac3178;hp=c32124dd0d0af372e247eb355d431bfdc8320fe5;hpb=c49960189a04b73e033016bd0f43fbb950f800e1;p=oweals%2Fbusybox.git diff --git a/init/init.c b/init/init.c index c32124dd0..f7eb8f34b 100644 --- a/init/init.c +++ b/init/init.c @@ -1,472 +1,999 @@ +/* vi: set sw=4 ts=4: */ /* * Mini init implementation for busybox * - * * Copyright (C) 1995, 1996 by Bruce Perens . + * Copyright (C) 1999-2004 by Erik Andersen * 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 -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include +#include "libbb.h" +#include #include -#include -#include -#include /* for serial_struct */ -#include /* for vt_stat */ -#include - -static const char init_usage[] = "Used internally by the system."; -static char console[16] = ""; -static const char* default_console = "/dev/tty2"; -static char* first_terminal = NULL; -static const char* second_terminal = "/dev/tty2"; -static const char* log = "/dev/tty3"; -static char* term_ptr = NULL; - -static void -message(const char* terminal, const char * pattern, ...) -{ - int fd; - FILE * con = 0; - va_list arguments; +#include - /* - * Open the console device each time a message is printed. If the user - * has switched consoles, the open will get the new console. If we kept - * the console open, we'd always print to the same one. - */ - if ( !terminal - || ((fd = open(terminal, O_WRONLY|O_NOCTTY)) < 0) - || ((con = fdopen(fd, "w")) == NULL) ) +#define INIT_BUFFS_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 + +#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 0x001 +#define RESPAWN 0x002 +#define ASKFIRST 0x004 +#define WAIT 0x008 +#define ONCE 0x010 +#define CTRLALTDEL 0x020 +#define SHUTDOWN 0x040 +#define RESTART 0x080 + +#define STR_SYSINIT "\x01" +#define STR_RESPAWN "\x02" +#define STR_ASKFIRST "\x04" +#define STR_WAIT "\x08" +#define STR_ONCE "\x10" +#define STR_CTRLALTDEL "\x20" +#define STR_SHUTDOWN "\x40" +#define STR_RESTART "\x80" + +/* 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; + char terminal[CONSOLE_NAME_SIZE]; + char command[INIT_BUFFS_SIZE]; +}; + +/* Static variables */ +static struct init_action *init_action_list = NULL; + +static const char *log_console = VC_5; +static sig_atomic_t got_cont = 0; + +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 +}; + +static const char *const environment[] = { + "HOME=/", + bb_PATH_root_path, + "SHELL=/bin/sh", + "USER=root", + NULL +}; + +/* Function prototypes */ +static void delete_init_action(struct init_action *a); +static void halt_reboot_pwoff(int sig) ATTRIBUTE_NORETURN; + +static void waitfor(pid_t pid) +{ + /* waitfor(run(x)): protect against failed fork inside run() */ + if (pid <= 0) return; - va_start(arguments, pattern); - vfprintf(con, pattern, arguments); + /* 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; +} + +static void loop_forever(void) ATTRIBUTE_NORETURN; +static void loop_forever(void) +{ + while (1) + sleep(1); +} + +/* Print a message to the specified device. + * Device may be bitwise-or'd from L_LOG | L_CONSOLE */ +#define messageD(...) do { if (ENABLE_DEBUG_INIT) message(__VA_ARGS__); } while (0) +static void message(int device, const char *fmt, ...) + __attribute__ ((format(printf, 2, 3))); +static void message(int device, const char *fmt, ...) +{ + static int log_fd = -1; + va_list arguments; + int l; + char msg[128]; + + msg[0] = '\r'; + va_start(arguments, fmt); + vsnprintf(msg + 1, sizeof(msg) - 2, fmt, arguments); va_end(arguments); - fclose(con); + msg[sizeof(msg) - 2] = '\0'; + l = strlen(msg); + + if (ENABLE_FEATURE_INIT_SYSLOG) { + /* Log the message to syslogd */ + if (device & L_LOG) { + /* don't out "\r" */ + openlog(applet_name, 0, LOG_DAEMON); + syslog(LOG_INFO, "init: %s", msg + 1); + closelog(); + } + msg[l++] = '\n'; + msg[l] = '\0'; + } else { + 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 = 2; + } 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); + device = L_CONSOLE; + } else { + close_on_exec_on(log_fd); + } + } + } + if (device & L_LOG) { + full_write(log_fd, msg, l); + if (log_fd == 2) + return; /* don't print dup messages */ + } + } + + if (device & L_CONSOLE) { + /* Send console messages to console so people will see them. */ + full_write(2, msg, l); + } } -static int -waitfor(int pid) +/* From */ +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) { - int status; - int wpid; - - message(log, "Waiting for process %d.\n", pid); - while ( (wpid = wait(&status)) != pid ) { - if ( wpid > 0 ) { - message( - log - ,"pid %d exited, status=%x.\n" - ,wpid - ,status); + 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, 0); + dup2(fd, 1); + dup2(fd, 2); + while (fd > 2) close(fd--); } + messageD(L_LOG, "console='%s'", s); + } else { + /* Make sure fd 0,1,2 are not closed */ + bb_sanitize_stdio(); } - return wpid; + + s = getenv("TERM"); + if (ioctl(0, 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"); } -static int -run(const char* program, const char* const* arguments, - const char* terminal, int get_enter) +/* Set terminal settings to reasonable defaults */ +static void set_sane_term(void) { - static const char control_characters[] = { - '\003', - '\034', - '\177', - '\025', - '\004', - '\0', - '\1', - '\0', - '\021', - '\023', - '\032', - '\0', - '\022', - '\017', - '\027', - '\026', - '\0' - }; - - static char * environment[] = { - "HOME=/", - "PATH=/bin:/sbin:/usr/bin:/usr/sbin", - "SHELL=/bin/sh", - 0, - "USER=root", - 0 - }; - - static const char press_enter[] = - "\nPlease press Enter to activate this console. "; - - int pid; - - environment[3]=term_ptr; + struct termios tty; - pid = fork(); - if ( pid == 0 ) { - struct termios t; - const char * const * arg; + tcgetattr(STDIN_FILENO, &tty); + + /* 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 */ + /* 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; + + /* 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(STDIN_FILENO, TCSANOW, &tty); +} + +/* Open the new terminal device */ +static void open_stdio_to_tty(const char* tty_name, int exit_on_failure) +{ + /* empty tty_name means "use init's tty", else... */ + if (tty_name[0]) { + int fd; close(0); - close(1); - close(2); - setsid(); - - open(terminal, O_RDWR); - dup(0); - dup(0); - tcsetpgrp(0, getpgrp()); - - tcgetattr(0, &t); - memcpy(t.c_cc, control_characters, sizeof(control_characters)); - t.c_line = 0; - t.c_iflag = ICRNL|IXON|IXOFF; - t.c_oflag = OPOST|ONLCR; - t.c_lflag = ISIG|ICANON|ECHO|ECHOE|ECHOK|ECHOCTL|ECHOKE|IEXTEN; - tcsetattr(0, TCSANOW, &t); - - if ( get_enter ) { - /* - * 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; - write(1, press_enter, sizeof(press_enter) - 1); - read(0, &c, 1); + /* 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(1); + if (ENABLE_DEBUG_INIT) + _exit(2); + halt_reboot_pwoff(SIGUSR1); /* halt the system */ + } + dup2(0, 1); + dup2(0, 2); + } + set_sane_term(); +} + +/* Used only by run_actions */ +static pid_t run(const struct init_action *a) +{ + int i; + pid_t pid; + char *s, *tmpCmd, *cmdpath; + char *cmd[INIT_BUFFS_SIZE]; + char buf[INIT_BUFFS_SIZE + 6]; /* INIT_BUFFS_SIZE+strlen("exec ")+1 */ + sigset_t nmask, omask; + + /* Block sigchild while forking (why?) */ + sigemptyset(&nmask); + sigaddset(&nmask, SIGCHLD); + sigprocmask(SIG_BLOCK, &nmask, &omask); + pid = fork(); + 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 */ + signal(SIGUSR1, SIG_DFL); + signal(SIGUSR2, SIG_DFL); + signal(SIGINT, SIG_DFL); + signal(SIGTERM, SIG_DFL); + signal(SIGHUP, SIG_DFL); + signal(SIGQUIT, SIG_DFL); + signal(SIGCONT, SIG_DFL); + signal(SIGSTOP, SIG_DFL); + signal(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*/); + +#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 & (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(1); + } + + if (pid > 0) { + /* Parent - wait till the child is done */ + signal(SIGINT, SIG_IGN); + signal(SIGTSTP, SIG_IGN); + signal(SIGQUIT, SIG_IGN); + signal(SIGCHLD, SIG_DFL); + + waitfor(pid); + /* See if stealing the controlling tty back is necessary */ + if (tcgetpgrp(0) != getpid()) + _exit(0); + + /* Use a temporary process to steal the controlling tty. */ + pid = fork(); + if (pid < 0) { + message(L_LOG | L_CONSOLE, "Can't fork"); + _exit(1); + } + if (pid == 0) { + setsid(); + ioctl(0, TIOCSCTTY, 1); + _exit(0); + } + waitfor(pid); + _exit(0); + } + + /* Child - fall though to actually execute things */ + } +#endif + + /* See if any special /bin/sh requiring characters are present */ + if (strpbrk(a->command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) { + cmd[0] = (char*)DEFAULT_SHELL; + cmd[1] = (char*)"-c"; + cmd[2] = strcat(strcpy(buf, "exec "), a->command); + cmd[3] = NULL; + } else { + /* Convert command (char*) into cmd (char**, one word per string) */ + strcpy(buf, a->command); + s = buf; + for (tmpCmd = buf, i = 0; (tmpCmd = strsep(&s, " \t")) != NULL;) { + if (*tmpCmd != '\0') { + cmd[i] = tmpCmd; + i++; + } + } + cmd[i] = NULL; + } + + cmdpath = cmd[0]; + + /* + * Interactive shells want to see a dash in argv[0]. This + * typically is handled by login, argv will be setup this + * way if a dash appears at the front of the command path + * (like "-/bin/sh"). + */ + if (*cmdpath == '-') { + /* skip over the dash */ + ++cmdpath; + +#ifdef WHY_WE_DO_THIS_SHELL_MUST_HANDLE_THIS_ITSELF + /* find the last component in the command pathname */ + s = bb_get_last_path_component_nostrip(cmdpath); + /* make a new argv[0] */ + cmd[0] = malloc(strlen(s) + 2); + if (cmd[0] == NULL) { + message(L_LOG | L_CONSOLE, bb_msg_memory_exhausted); + cmd[0] = cmdpath; + } else { + cmd[0][0] = '-'; + strcpy(cmd[0] + 1, s); + } +#endif + + /* _Attempt_ to make stdin a controlling tty. */ + if (ENABLE_FEATURE_INIT_SCTTY) + ioctl(0, TIOCSCTTY, 0 /*only try, don't steal*/); + } + + if (a->action & 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", + cmdpath, getpid(), a->terminal); + full_write(1, press_enter, sizeof(press_enter) - 1); + while (safe_read(0, &c, 1) == 1 && c != '\n') + continue; + } + + /* Log the process name and args */ + message(L_LOG, "starting pid %d, tty '%s': '%s'", + getpid(), a->terminal, cmdpath); + + 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); } - - message(log, "Executing "); - arg = arguments; - while ( *arg != 0 ) - message(log, "%s ", *arg++); - message(log, "\n"); - - execve(program, (char * *)arguments, (char * *)environment); - message(log, "%s: could not execute: %s.\r\n", program, strerror(errno)); - exit(-1); } - return pid; + + /* Now run it. The new program will take over this PID, + * so nothing further in init.c should be run. */ + BB_EXECVP(cmdpath, cmd); + + /* We're still here? Some error happened. */ + message(L_LOG | L_CONSOLE, "Cannot run '%s': %s", + cmdpath, strerror(errno)); + _exit(-1); } -static int -mem_total() +/* Run all commands of a particular type */ +static void run_actions(int action) { - char s[80]; - char *p; - FILE *f; - const char pattern[]="MemTotal:"; - - f=fopen("/proc/meminfo","r"); - while (NULL != fgets(s,79,f)) { - p=strstr(s, pattern); - if (NULL != p) { - fclose(f); - return(atoi(p+strlen(pattern))); + struct init_action *a, *tmp; + + for (a = init_action_list; a; a = tmp) { + tmp = a->next; + if (a->action == action) { + // 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 & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) { + waitfor(run(a)); + delete_init_action(a); + } else if (a->action & ONCE) { + run(a); + delete_init_action(a); + } else if (a->action & (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); + } + } + } } - } - return -1; } -static void -set_free_pages() +static void init_reboot(unsigned long magic) { - char s[80]; - FILE *f; - - f=fopen("/proc/sys/vm/freepages","r"); - fgets(s,79,f); - if (atoi(s) < 32) { - fclose(f); - f=fopen("/proc/sys/vm/freepages","w"); - fprintf(f,"30\t40\t50\n"); - printf("\nIncreased /proc/sys/vm/freepages values to 30/40/50\n"); - } - fclose(f); + pid_t pid; + /* We have to fork here, since the kernel calls do_exit(0) 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(0); + } + waitfor(pid); } -static void -shutdown_system(void) +static void kill_all_processes(void) { - static const char * const umount_args[] = {"/bin/umount", "-a", "-n", 0}; - static const char * const swapoff_args[] = {"/bin/swapoff", "-a", 0}; + sigset_t block_signals; + + /* 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); + + /* first disable all our signals */ + sigfillset(&block_signals); + /*sigemptyset(&block_signals); + sigaddset(&block_signals, SIGHUP); + sigaddset(&block_signals, SIGQUIT); + sigaddset(&block_signals, SIGCHLD); + sigaddset(&block_signals, SIGUSR1); + sigaddset(&block_signals, SIGUSR2); + sigaddset(&block_signals, SIGINT); + sigaddset(&block_signals, SIGTERM); + sigaddset(&block_signals, SIGCONT); + sigaddset(&block_signals, SIGSTOP); + sigaddset(&block_signals, SIGTSTP);*/ + sigprocmask(SIG_BLOCK, &block_signals, NULL); + + message(L_CONSOLE | L_LOG, "The system is going down NOW!"); - message(console, "The system is going down NOW !!"); - sync(); /* Allow Ctrl-Alt-Del to reboot system. */ - reboot(RB_ENABLE_CAD); + init_reboot(RB_ENABLE_CAD); /* Send signals to every process _except_ pid 1 */ - message(console, "Sending SIGHUP to all processes.\r\n"); - kill(-1, SIGHUP); - sleep(2); + message(L_CONSOLE | L_LOG, "Sending SIG%s to all processes", "TERM"); + kill(-1, SIGTERM); sync(); - message(console, "Sending SIGKILL to all processes.\r\n"); - kill(-1, SIGKILL); sleep(1); - waitfor(run("/bin/swapoff", swapoff_args, console, 0)); - waitfor(run("/bin/umount", umount_args, console, 0)); + + message(L_CONSOLE | L_LOG, "Sending SIG%s to all processes", "KILL"); + kill(-1, SIGKILL); sync(); - if (get_kernel_revision() <= 2*65536+2*256+11) { - /* Removed bdflush call, kupdate in kernels >2.2.11 */ - bdflush(1, 0); - sync(); + sleep(1); +} + +static void halt_reboot_pwoff(int sig) +{ + const char *m; + int rb; + + kill_all_processes(); + + m = "halt"; + 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(); +} + +/* Handler for HUP and QUIT - exec "restart" action, + * else (no such action defined) do nothing */ +static void exec_restart_action(int sig ATTRIBUTE_UNUSED) +{ + struct init_action *a, *tmp; + sigset_t unblock_signals; + + for (a = init_action_list; a; a = tmp) { + tmp = a->next; + if (a->action & RESTART) { + kill_all_processes(); + + /* unblock all signals (blocked in kill_all_processes()) */ + sigfillset(&unblock_signals); + /*sigemptyset(&unblock_signals); + sigaddset(&unblock_signals, SIGHUP); + sigaddset(&unblock_signals, SIGQUIT); + sigaddset(&unblock_signals, SIGCHLD); + sigaddset(&unblock_signals, SIGUSR1); + sigaddset(&unblock_signals, SIGUSR2); + sigaddset(&unblock_signals, SIGINT); + sigaddset(&unblock_signals, SIGTERM); + sigaddset(&unblock_signals, SIGCONT); + sigaddset(&unblock_signals, SIGSTOP); + sigaddset(&unblock_signals, SIGTSTP);*/ + sigprocmask(SIG_UNBLOCK, &unblock_signals, NULL); + + /* 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); + BB_EXECLP(a->command, a->command, NULL); + + message(L_CONSOLE | L_LOG, "Cannot run '%s': %s", + a->command, strerror(errno)); + sleep(2); + init_reboot(RB_HALT_SYSTEM); + loop_forever(); + } } } -static void -halt_signal(int sig) +static void ctrlaltdel_signal(int sig ATTRIBUTE_UNUSED) { - shutdown_system(); - message(console, "The system is halted. Press CTRL-ALT-DEL or turn off power\r\n"); - reboot( RB_HALT_SYSTEM); - exit(0); + run_actions(CTRLALTDEL); } -static void -reboot_signal(int sig) +/* The SIGSTOP & SIGTSTP handler */ +static void stop_handler(int sig ATTRIBUTE_UNUSED) { - shutdown_system(); - message(console, "Please stand by while rebooting the system.\r\n"); - reboot( RB_AUTOBOOT); - exit(0); + int saved_errno = errno; + + got_cont = 0; + while (!got_cont) + pause(); + + errno = saved_errno; } -static void -configure_terminals( int serial_cons, int single_user_mode ) +/* The SIGCONT handler */ +static void cont_handler(int sig ATTRIBUTE_UNUSED) { - char *tty; - struct serial_struct sr; - struct vt_stat vt; - - - switch (serial_cons) { - case -1: - /* 2.2 kernels: - * identify the real console backend and try to make use of it */ - if (ioctl(0,TIOCGSERIAL,&sr) == 0) { - sprintf( console, "/dev/ttyS%d", sr.line ); - serial_cons = sr.line+1; - } - else if (ioctl(0, VT_GETSTATE, &vt) == 0) { - sprintf( console, "/dev/tty%d", vt.v_active ); - serial_cons = 0; - } - else { - /* unknown backend: fallback to /dev/console */ - strcpy( console, "/dev/console" ); - serial_cons = 0; - } - break; - - case 1: - strcpy( console, "/dev/cua0" ); - break; - case 2: - strcpy( console, "/dev/cua1" ); - break; - default: - tty = ttyname(0); - if (tty) { - strcpy( console, tty ); - if (!strncmp( tty, "/dev/cua", 8 )) - serial_cons=1; + got_cont = 1; +} + +static void new_init_action(uint8_t action, const char *command, const char *cons) +{ + struct init_action *new_action, *a, *last; + + 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 = action; + return; } - else - /* falls back to /dev/tty1 if an error occurs */ - strcpy( console, default_console ); + last = a; } - if (!first_terminal) - first_terminal = console; -#if defined (__sparc__) - if (serial_cons > 0 && !strncmp(term_ptr,"TERM=linux",10)) - term_ptr = "TERM=vt100"; -#endif - if (serial_cons) { - /* disable other but the first terminal: - * VT is not initialized anymore on 2.2 kernel when booting from - * serial console, therefore modprobe is flooding the display with - * "can't locate module char-major-4" messages. */ - log = 0; - second_terminal = 0; + + new_action = xzalloc(sizeof(struct init_action)); + if (last) { + last->next = new_action; + } else { + init_action_list = new_action; + } + strcpy(new_action->command, command); + new_action->action = action; + strcpy(new_action->terminal, cons); + messageD(L_LOG | L_CONSOLE, "command='%s' action=%d tty='%s'\n", + new_action->command, new_action->action, new_action->terminal); +} + +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; + } } } -extern int -init_main(int argc, char * * argv) +/* 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) { - const char * rc_arguments[100]; - const char * arguments[100]; - int run_rc = TRUE; - int j; - int pid1 = 0; - int pid2 = 0; - struct stat statbuf; - const char * tty_commands[3] = { "etc/init.d/rcS", "bin/sh"}; - int serial_console = 0; - int retval; + FILE *file; + char buf[INIT_BUFFS_SIZE]; + + if (ENABLE_FEATURE_USE_INITTAB) + file = fopen(INITTAB, "r"); + else + file = NULL; + + /* No inittab file -- set up some default behavior */ + if (file == 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 HUP is received */ + new_init_action(RESTART, "init", ""); + /* Askfirst shell on tty1-4 */ + new_init_action(ASKFIRST, bb_default_login_shell, ""); + 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, ""); - /* - * If I am started as /linuxrc instead of /sbin/init, I don't have the - * environment that init expects. I can't fix the signal behavior. Try - * to divorce from the controlling terminal with setsid(). This won't work - * if I am the process group leader. - */ - setsid(); + return; + } - signal(SIGUSR1, halt_signal); - signal(SIGUSR2, reboot_signal); - signal(SIGINT, reboot_signal); - signal(SIGTERM, reboot_signal); + while (fgets(buf, INIT_BUFFS_SIZE, file) != NULL) { + static const char actions[] = + STR_SYSINIT "sysinit\0" + STR_RESPAWN "respawn\0" + STR_ASKFIRST "askfirst\0" + STR_WAIT "wait\0" + STR_ONCE "once\0" + STR_CTRLALTDEL "ctrlaltdel\0" + STR_SHUTDOWN "shutdown\0" + STR_RESTART "restart\0" + ; + char tmpConsole[CONSOLE_NAME_SIZE]; + char *id, *runlev, *action, *command; + const char *a; + + /* Skip leading spaces */ + id = skip_whitespace(buf); + /* Skip the line if it's a comment */ + if (*id == '#' || *id == '\n') + continue; + /* Trim the trailing '\n' */ + *strchrnul(id, '\n') = '\0'; + + /* Line is: "id:runlevel_ignored:action:command" */ + runlev = strchr(id, ':'); + if (runlev == NULL /*|| runlev[1] == '\0' - not needed */) + goto bad_entry; + action = strchr(runlev + 1, ':'); + if (action == NULL /*|| action[1] == '\0' - not needed */) + goto bad_entry; + command = strchr(action + 1, ':'); + if (command == NULL || command[1] == '\0') + goto bad_entry; + + *command = '\0'; /* action => ":action\0" now */ + for (a = actions; a[0]; a += strlen(a) + 1) { + if (strcmp(a + 1, action + 1) == 0) { + *runlev = '\0'; + if (*id != '\0') { + if (strncmp(id, "/dev/", 5) == 0) + id += 5; + strcpy(tmpConsole, "/dev/"); + safe_strncpy(tmpConsole + 5, id, + sizeof(tmpConsole) - 5); + id = tmpConsole; + } + new_init_action((uint8_t)a[0], command + 1, id); + goto next_line; + } + } + *command = ':'; + /* Choke on an unknown action */ + bad_entry: + message(L_LOG | L_CONSOLE, "Bad inittab entry: %s", id); + next_line: ; + } + fclose(file); +} - reboot(RB_DISABLE_CAD); +static void reload_signal(int sig ATTRIBUTE_UNUSED) +{ + struct init_action *a, *tmp; - message(log, "%s: started. ", argv[0]); + message(L_LOG, "reloading /etc/inittab"); - for ( j = 1; j < argc; j++ ) { - if ( strcmp(argv[j], "single") == 0 ) { - run_rc = FALSE; - tty_commands[0] = "bin/sh"; - tty_commands[1] = 0; - } + /* disable old entrys */ + for (a = init_action_list; a; a = a->next) { + a->action = ONCE; } - for ( j = 0; __environ[j] != 0; j++ ) { - if ( strncmp(__environ[j], "tty", 3) == 0 - && __environ[j][3] >= '1' - && __environ[j][3] <= '2' - && __environ[j][4] == '=' ) { - const char * s = &__environ[j][5]; - if ( *s == 0 || strcmp(s, "off") == 0 ) - s = 0; + parse_inittab(); - tty_commands[__environ[j][3] - '1'] = s; - } - /* Should catch the syntax of Sparc kernel console setting. */ - /* The kernel does not recognize a serial console when getting*/ - /* console=/dev/ttySX !! */ - else if ( strcmp(__environ[j], "console=ttya") == 0 ) { - serial_console=1; + 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 & ONCE) && pid != 0) { + kill(pid, SIGTERM); + } } - else if ( strcmp(__environ[j], "console=ttyb") == 0 ) { - serial_console=2; - } - /* standard console settings */ - else if ( strncmp(__environ[j], "console=", 8) == 0 ) { - first_terminal=&(__environ[j][8]); - } - else if ( strncmp(__environ[j], "TERM=", 5) == 0) { - term_ptr=__environ[j]; +#if CONFIG_FEATURE_KILL_DELAY + if (fork() == 0) { /* child */ + sleep(CONFIG_FEATURE_KILL_DELAY); + for (a = init_action_list; a; a = a->next) { + pid_t pid = a->pid; + if ((a->action & ONCE) && pid != 0) { + kill(pid, SIGKILL); + } + } + _exit(0); } +#endif } - printf("mounting /proc ...\n"); - if (mount("/proc","/proc","proc",0,0)) { - perror("mounting /proc failed\n"); + /* remove unused entrys */ + for (a = init_action_list; a; a = tmp) { + tmp = a->next; + if ((a->action & (ONCE | SYSINIT | WAIT)) && a->pid == 0) { + delete_init_action(a); + } } - printf("\tdone.\n"); + run_actions(RESPAWN); +} + +int init_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; +int init_main(int argc, char **argv) +{ + struct init_action *a; + pid_t wpid; - if (get_kernel_revision() >= 2*65536+1*256+71) { - /* if >= 2.1.71 kernel, /dev/console is not a symlink anymore: - * use it as primary console */ - serial_console=-1; + die_sleep = 30 * 24*60*60; /* if xmalloc will ever die... */ + + if (argc > 1 && !strcmp(argv[1], "-q")) { + return kill(1, SIGHUP); } - /* Make sure /etc/init.d/rc exists */ - retval= stat(tty_commands[0],&statbuf); - if (retval) - run_rc = FALSE; - - configure_terminals( serial_console, run_rc); - - set_free_pages(); - - /* not enough memory to do anything useful*/ - if (mem_total() < 2000) { - retval= stat("/etc/fstab",&statbuf); - if (retval) { - printf("You do not have enough RAM, sorry.\n"); - while (1) { sleep(1);} - } else { - /* Try to turn on swap */ - static const char * const swapon_args[] = {"/bin/swapon", "-a", 0}; - waitfor(run("/bin/swapon", swapon_args, console, 0)); - if (mem_total() < 2000) { - printf("You do not have enough RAM, sorry.\n"); - while (1) { sleep(1);} + if (!ENABLE_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(SIGHUP, exec_restart_action); + signal(SIGQUIT, exec_restart_action); + signal(SIGUSR1, halt_reboot_pwoff); /* halt */ + signal(SIGUSR2, halt_reboot_pwoff); /* poweroff */ + signal(SIGTERM, halt_reboot_pwoff); /* reboot */ + signal(SIGINT, ctrlaltdel_signal); + signal(SIGCONT, cont_handler); + signal(SIGSTOP, stop_handler); + signal(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); } - /* - * Don't modify **argv directly, it would show up in the "ps" display. - * I don't want "init" to look like "rc". - */ - rc_arguments[0] = tty_commands[0]; - for ( j = 1; j < argc; j++ ) { - rc_arguments[j] = argv[j]; + /* Figure out where the default console should be */ + console_init(); + set_sane_term(); + chdir("/"); + setsid(); + { + const char *const *e; + /* Make sure environs is set to something sane */ + for (e = environment; *e; e++) + putenv((char *) *e); } - rc_arguments[j] = 0; - arguments[0] = "-sh"; - arguments[1] = 0; - - /* Ok, now launch the rc script /etc/init.d/rcS and prepare to start up - * some VTs on tty1 and tty2 if somebody hits enter - */ - for ( ; ; ) { - int wpid; - int status; - - if ( pid1 == 0 && tty_commands[0] ) { - if ( run_rc == TRUE ) { - pid1 = run(tty_commands[0], rc_arguments, first_terminal, 0); - } else { - pid2 = run(tty_commands[1], arguments, first_terminal, 1); - } - } - if ( pid2 == 0 && second_terminal && tty_commands[1] ) { - pid2 = run(tty_commands[1], arguments, second_terminal, 1); + if (argc > 1) setenv("RUNLEVEL", argv[1], 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 */ } - wpid = wait(&status); - if ( wpid > 0 && wpid != pid1) { - message(log, "pid %d exited, status=%x.\n", wpid, status); + } + + /* Check if we are supposed to be in single user mode */ + if (argc > 1 + && (!strcmp(argv[1], "single") || !strcmp(argv[1], "-s") || LONE_CHAR(argv[1], '1')) + ) { + /* 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(); + } + +#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(1); } - if ( wpid == pid2 ) { - pid2 = 0; + } +#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); + + /* Now run the looping stuff for the rest of forever */ + while (1) { + /* run the respawn stuff */ + run_actions(RESPAWN); + + /* run the askfirst stuff */ + run_actions(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 it for restart.", + a->command, wpid); + } + } + /* see if anyone else is waiting to be reaped */ + wpid = wait_any_nohang(NULL); } } } -