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This commit is contained in:
Eric Andersen 1999-10-25 23:32:44 +00:00
parent d143e8f2bd
commit 0460ff2e5d
13 changed files with 931 additions and 618 deletions
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3
Changelog
View File

@ -4,6 +4,9 @@
* Fixed mkdir -m option so that it works.
* kill segfaulted w/o any arguments. Now it doesn't do that.
* kill wasn't properly accepting signal names. It does now.
* Added new apps chvt and deallocvt
* Major adjustment of init.c. Code is now readable IMHO,
and much more solid.
-Erik Andersen

2
Makefile
View File

@ -22,7 +22,7 @@ BUILDTIME=$(shell date "+%Y%m%d-%H%M")
# Comment out the following to make a debuggable build
# Leave this off for production use.
DODEBUG=false
DODEBUG=true
# If you want a static binary, turn this on. I can't think
# of many situations where anybody would ever want it static,
# but...

9
applets/busybox.c
View File

@ -51,6 +51,12 @@ static const struct Applet applets[] = {
#ifdef BB_FIND //usr/bin
{"find", find_main},
#endif
#ifdef BB_CHVT //usr/bin
{"chvt", chvt_main},
#endif
#ifdef BB_DEALLOCVT //usr/bin
{"deallocvt", deallocvt_main},
#endif
#ifdef BB_FSCK_MINIX //sbin
{"fsck.minix", fsck_minix_main},
#endif
@ -156,6 +162,9 @@ static const struct Applet applets[] = {
{"true", true_main},
{"false", false_main},
#endif
#ifdef BB_UNAME //bin
{"uname", uname_main},
#endif
#ifdef BB_UMOUNT //bin
{"umount", umount_main},
#endif

9
busybox.c
View File

@ -51,6 +51,12 @@ static const struct Applet applets[] = {
#ifdef BB_FIND //usr/bin
{"find", find_main},
#endif
#ifdef BB_CHVT //usr/bin
{"chvt", chvt_main},
#endif
#ifdef BB_DEALLOCVT //usr/bin
{"deallocvt", deallocvt_main},
#endif
#ifdef BB_FSCK_MINIX //sbin
{"fsck.minix", fsck_minix_main},
#endif
@ -156,6 +162,9 @@ static const struct Applet applets[] = {
{"true", true_main},
{"false", false_main},
#endif
#ifdef BB_UNAME //bin
{"uname", uname_main},
#endif
#ifdef BB_UMOUNT //bin
{"umount", umount_main},
#endif

3
busybox.def.h
View File

@ -18,6 +18,8 @@
#define BB_FIND
//#define BB_FSCK_MINIX
//#define BB_MKFS_MINIX
#define BB_CHVT
#define BB_DEALLOCVT
#define BB_GREP
//#define BB_HALT
#define BB_INIT
@ -53,6 +55,7 @@
//#define BB_TRUE_FALSE // Supplied by ash
#define BB_UMOUNT
#define BB_UPDATE
#define BB_UNAME
#define BB_ZCAT
//#define BB_GZIP
// Don't turn BB_UTILITY off. It contains support code

36
chvt.c Normal file
View File

@ -0,0 +1,36 @@
/*
* chvt.c - aeb - 940227 - Change virtual terminal
*
* busyboxed by Erik Andersen
*/
#include "internal.h"
#include <sys/types.h>
#include <sys/ioctl.h>
#include <linux/vt.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
extern int getfd(void);
int
chvt_main(int argc, char** argv)
{
int fd, num;
if ( ( argc != 2) || (**(argv+1) == '-' ) ) {
usage ("chvt </dev/ttyN>\n");
}
fd = get_console_fd("/dev/console");
num = atoi(argv[1]);
if (ioctl(fd,VT_ACTIVATE,num)) {
perror("VT_ACTIVATE");
exit(FALSE);
}
if (ioctl(fd,VT_WAITACTIVE,num)) {
perror("VT_WAITACTIVE");
exit(FALSE);
}
exit( TRUE);
}

36
console-tools/chvt.c Normal file
View File

@ -0,0 +1,36 @@
/*
* chvt.c - aeb - 940227 - Change virtual terminal
*
* busyboxed by Erik Andersen
*/
#include "internal.h"
#include <sys/types.h>
#include <sys/ioctl.h>
#include <linux/vt.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
extern int getfd(void);
int
chvt_main(int argc, char** argv)
{
int fd, num;
if ( ( argc != 2) || (**(argv+1) == '-' ) ) {
usage ("chvt </dev/ttyN>\n");
}
fd = get_console_fd("/dev/console");
num = atoi(argv[1]);
if (ioctl(fd,VT_ACTIVATE,num)) {
perror("VT_ACTIVATE");
exit(FALSE);
}
if (ioctl(fd,VT_WAITACTIVE,num)) {
perror("VT_WAITACTIVE");
exit(FALSE);
}
exit( TRUE);
}

47
console-tools/deallocvt.c Normal file
View File

@ -0,0 +1,47 @@
/*
* disalloc.c - aeb - 940501 - Disallocate virtual terminal(s)
* Renamed deallocvt.
*/
#include <stdlib.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <linux/vt.h>
#include <stdio.h>
extern int getfd(void);
char *progname;
int
deallocvt_main(int argc, char *argv[]) {
int fd, num, i;
if (argc < 1) /* unlikely */
exit(1);
progname = argv[0];
fd = get_console_fd("/dev/console");
if (argc == 1) {
/* deallocate all unused consoles */
if (ioctl(fd,VT_DISALLOCATE,0)) {
perror("VT_DISALLOCATE");
exit(1);
}
} else
for (i = 1; i < argc; i++) {
num = atoi(argv[i]);
if (num == 0)
fprintf(stderr, "%s: 0: illegal VT number\n", progname);
else if (num == 1)
fprintf(stderr, "%s: VT 1 cannot be deallocated\n", progname);
else
if (ioctl(fd,VT_DISALLOCATE,num)) {
perror("VT_DISALLOCATE");
fprintf(stderr, "%s: could not deallocate console %d\n",
progname, num);
exit(1);
}
}
exit(0);
}

47
deallocvt.c Normal file
View File

@ -0,0 +1,47 @@
/*
* disalloc.c - aeb - 940501 - Disallocate virtual terminal(s)
* Renamed deallocvt.
*/
#include <stdlib.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <linux/vt.h>
#include <stdio.h>
extern int getfd(void);
char *progname;
int
deallocvt_main(int argc, char *argv[]) {
int fd, num, i;
if (argc < 1) /* unlikely */
exit(1);
progname = argv[0];
fd = get_console_fd("/dev/console");
if (argc == 1) {
/* deallocate all unused consoles */
if (ioctl(fd,VT_DISALLOCATE,0)) {
perror("VT_DISALLOCATE");
exit(1);
}
} else
for (i = 1; i < argc; i++) {
num = atoi(argv[i]);
if (num == 0)
fprintf(stderr, "%s: 0: illegal VT number\n", progname);
else if (num == 1)
fprintf(stderr, "%s: VT 1 cannot be deallocated\n", progname);
else
if (ioctl(fd,VT_DISALLOCATE,num)) {
perror("VT_DISALLOCATE");
fprintf(stderr, "%s: could not deallocate console %d\n",
progname, num);
exit(1);
}
}
exit(0);
}

630
init.c
View File

@ -41,144 +41,88 @@
#include <sys/vt.h> /* for vt_stat */
#include <sys/ioctl.h>
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;
#define DEBUG_INIT
static void
message(const char* terminal, const char * pattern, ...)
#define CONSOLE "/dev/console" /* Logical system console */
#define VT_PRIMARY "/dev/tty0" /* Virtual console master */
#define VT_SECONDARY "/dev/tty1" /* Virtual console master */
#define VT_LOG "/dev/tty2" /* Virtual console master */
#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"
static int maxproclen=0;
static char* argv0;
static char* console = CONSOLE;
static char* second_terminal = "/dev/tty2";
static char* log = "/dev/tty3";
/* try to open up the specified device */
int device_open(char* device, int mode)
{
int fd;
FILE * con = 0;
va_list arguments;
int m, f, fd = -1;
mode = m | 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;
/* Set original flags. */
if (m != mode)
fcntl(fd, F_SETFL, mode);
return fd;
}
/*
* 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) )
return;
va_start(arguments, pattern);
vfprintf(con, pattern, arguments);
/* print a message to the specified device */
void message(char* device, char *fmt, ...)
{
int fd;
va_list arguments;
if ((fd = device_open(device, O_WRONLY|O_NOCTTY|O_NDELAY)) >= 0) {
va_start(arguments, fmt);
vdprintf(fd, fmt, arguments);
va_end(arguments);
fclose(con);
}
close( fd);
}
static int
waitfor(int pid)
/* Set terminal settings to reasonable defaults */
void set_term()
{
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);
}
}
return wpid;
}
int fd;
struct termios tty;
static int
run(const char* program, const char* const* arguments,
const char* terminal, int get_enter)
{
static const char control_characters[] = {
'\003',
'\034',
'\177',
'\025',
'\004',
'\0',
'\1',
'\0',
'\021',
'\023',
'\032',
'\0',
'\022',
'\017',
'\027',
'\026',
'\0'
};
if ((fd = device_open(console, O_RDWR|O_NOCTTY)) < 0) {
message(log, "can't open %s", console);
return;
}
ioctl(fd, TCGETS, &tty);
tty.c_cflag &= CBAUD|CBAUDEX|CSIZE|CSTOPB|PARENB|PARODD;
tty.c_cflag |= HUPCL|CLOCAL;
static char * environment[] = {
"HOME=/",
"PATH=/bin:/sbin:/usr/bin:/usr/sbin",
"SHELL=/bin/sh",
0,
"USER=root",
0
};
tty.c_cc[VINTR] = 3;
tty.c_cc[VQUIT] = 28;
tty.c_cc[VERASE] = 127;
tty.c_cc[VKILL] = 24;
tty.c_cc[VEOF] = 4;
tty.c_cc[VTIME] = 0;
tty.c_cc[VMIN] = 1;
tty.c_cc[VSTART] = 17;
tty.c_cc[VSTOP] = 19;
tty.c_cc[VSUSP] = 26;
static const char press_enter[] =
"\nPlease press Enter to activate this console. ";
/* Set pre and post processing */
tty.c_iflag = IGNPAR|ICRNL|IXON|IXANY;
tty.c_oflag = OPOST|ONLCR;
tty.c_lflag = ISIG|ICANON|ECHO|ECHOCTL|ECHOPRT|ECHOKE;
int pid;
environment[3]=term_ptr;
pid = fork();
if ( pid == 0 ) {
struct termios t;
const char * const * arg;
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);
}
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 set the terminal line. */
ioctl(fd, TCSETS, &tty);
close( fd);
}
static int
@ -217,33 +161,168 @@ set_free_pages()
fclose(f);
}
static void
console_init()
{
int fd;
int tried_devcons = 0;
int tried_vtmaster = 0;
char *s;
if ((s = getenv("CONSOLE")) != NULL)
console = s;
else {
console = CONSOLE;
tried_devcons++;
}
while ((fd = open(console, O_RDONLY|O_NONBLOCK)) < 0) {
if (!tried_devcons) {
tried_devcons++;
console = CONSOLE;
continue;
}
if (!tried_vtmaster) {
tried_vtmaster++;
console = VT_PRIMARY;
continue;
}
break;
}
if (fd < 0)
console = "/dev/null";
else
close(fd);
}
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=%x.\n", wpid, status);
}
return wpid;
}
static int
run(const char* command, char* terminal, int get_enter)
{
int f, pid;
char *args[16];
char buf[256];
char* ptr;
static const char press_enter[] =
"\nPlease press Enter to activate this console. ";
/* Make a proper command from the command string */
strcpy(buf, command);
ptr = buf;
for(f = 1; f < 15; f++) {
/* Skip white space */
while(*ptr == ' ' || *ptr == '\t') ptr++;
args[f] = ptr;
/* May be trailing space.. */
if (*ptr == 0) break;
/* Skip this `word' */
while(*ptr && *ptr != ' ' && *ptr != '\t' && *ptr != '#')
ptr++;
/* If end-of-line, break */
if (*ptr == '#' || *ptr == 0) {
f++;
*ptr = 0;
break;
}
/* End word with \0 and continue */
args[f] = NULL;
}
args[0] = args[1];
if ((pid = fork()) == 0) {
/* Clean up */
close(0);
close(1);
close(2);
setsid();
if ((f = device_open(terminal, O_RDWR|O_NOCTTY)) < 0) {
message( log, "open(%s) failed: %s", terminal, strerror(errno));
return -1;
}
dup(f);
dup(f);
tcsetpgrp(0, getpgrp());
set_term();
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);
}
/* Log the process name and args */
message(log, "Executing '%s'\n", command);
/* Now run it. This should take over the PID, so nothing
* further in init.c should be run by this PID. */
execvp(args[1], args + 1);
/* If shell scripts are not executed, force the issue */
if (errno == ENOEXEC) {
char buf[256];
args[1] = SHELL;
args[2] = "-c";
strcpy(buf, "exec ");
strcat(buf, command);
args[3] = buf;
args[4] = NULL;
execvp(args[1], args + 1);
}
message(log, "Could not execute '%s'\n", command, strerror(errno));
exit(-1);
}
return pid;
}
#ifndef DEBUG_INIT
static void
shutdown_system(void)
{
static const char * const umount_args[] = {"/bin/umount", "-a", "-n", 0};
static const char * const swapoff_args[] = {"/bin/swapoff", "-a", 0};
message(console, "The system is going down NOW !!");
sync();
/* Allow Ctrl-Alt-Del to reboot system. */
reboot(RB_ENABLE_CAD);
message(console, "The system is going down NOW !!");
sync();
/* Allow Ctrl-Alt-Del to reboot system. */
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);
/* Send signals to every process _except_ pid 1 */
message(console, "Sending SIGHUP to all processes.\r\n");
kill(-1, SIGHUP);
sleep(2);
sync();
message(console, "Sending SIGKILL to all processes.\r\n");
kill(-1, SIGKILL);
sleep(1);
waitfor(run("/bin/swapoff -a", console, 0));
waitfor(run("/bin/umount -a -n", console, 0));
sync();
if (get_kernel_revision() <= 2*65536+2*256+11) {
/* Removed bdflush call, kupdate in kernels >2.2.11 */
bdflush(1, 0);
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));
sync();
if (get_kernel_revision() <= 2*65536+2*256+11) {
/* Removed bdflush call, kupdate in kernels >2.2.11 */
bdflush(1, 0);
sync();
}
}
}
static void
@ -251,7 +330,7 @@ halt_signal(int sig)
{
shutdown_system();
message(console, "The system is halted. Press CTRL-ALT-DEL or turn off power\r\n");
reboot( RB_HALT_SYSTEM);
reboot( RB_POWER_OFF);
exit(0);
}
@ -263,202 +342,136 @@ reboot_signal(int sig)
reboot( RB_AUTOBOOT);
exit(0);
}
static void
configure_terminals( int serial_cons, int single_user_mode )
{
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;
}
else
/* falls back to /dev/tty1 if an error occurs */
strcpy( console, default_console );
}
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;
}
int setproctitle(char *fmt, ...)
{
va_list ap;
int len;
char buf[256];
buf[0] = 0;
va_start(ap, fmt);
len = vsprintf(buf, fmt, ap);
va_end(ap);
memset(argv0, 0, maxproclen + 1);
strncpy(argv0, buf, maxproclen);
return len;
}
extern int
init_main(int argc, char * * argv)
{
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;
int run_rc = TRUE;
int pid1 = 0;
int pid2 = 0;
struct stat statbuf;
const char* init_commands = SHELL "-c exec " INITSCRIPT;
const char* shell_commands = SHELL;
const char* tty0_commands = init_commands;
const char* tty1_commands = shell_commands;
const char* no_memory =
"Sorry, your computer does not have enough memory.\n";
/*
* 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.
*/
/* For later use */
argv0 = argv[0];
maxproclen = strlen(argv[0]);
setproctitle("init [boot]");
#ifndef DEBUG_INIT
/* Set up sig handlers */
signal(SIGUSR1, halt_signal);
signal(SIGSEGV, halt_signal);
signal(SIGPWR, halt_signal);
signal(SIGALRM, halt_signal);
signal(SIGHUP, halt_signal);
signal(SIGUSR2, reboot_signal);
signal(SIGINT, reboot_signal);
signal(SIGTERM, reboot_signal);
#endif
/* Figure out where the default console should be */
console_init();
/* 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
/* Close whatever files are open, and reset the console. */
close(0);
close(1);
close(2);
set_term();
setsid();
signal(SIGUSR1, halt_signal);
signal(SIGUSR2, reboot_signal);
signal(SIGINT, reboot_signal);
signal(SIGTERM, reboot_signal);
/* Make sure PATH is set to something sane */
if (getenv("PATH") == NULL)
putenv(PATH_DEFAULT);
reboot(RB_DISABLE_CAD);
/* Hello world */
message(console, "%s started: BusyBox v%s (%s) multi-call binary",
argv[0], BB_VER, BB_BT);
message(log, "%s started: BusyBox v%s (%s) multi-call binary",
argv[0], BB_VER, BB_BT);
message(log, "%s: started. ", argv[0]);
for ( j = 1; j < argc; j++ ) {
if ( strcmp(argv[j], "single") == 0 ) {
run_rc = FALSE;
tty_commands[0] = "bin/sh";
tty_commands[1] = 0;
}
}
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;
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;
}
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];
}
}
printf("mounting /proc ...\n");
/* Mount /proc */
message(console, "Mounting /proc: \n");
if (mount("/proc","/proc","proc",0,0)) {
perror("mounting /proc failed\n");
message(log, "%s: could not mount /proc!\n", argv[0]);
message(console, "failed!\n");
}
printf("\tdone.\n");
message(console, "done.\n");
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;
}
/* Make sure /etc/init.d/rc exists */
retval= stat(tty_commands[0],&statbuf);
if (retval)
run_rc = FALSE;
configure_terminals( serial_console, run_rc);
/* Make sure there is enough memory to do something useful*/
set_free_pages();
/* not enough memory to do anything useful*/
if (mem_total() < 2000) {
int retval;
retval= stat("/etc/fstab",&statbuf);
if (retval) {
printf("You do not have enough RAM, sorry.\n");
message(console, "%s", no_memory);
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));
waitfor(run("/bin/swapon -a", console, 0));
if (mem_total() < 2000) {
printf("You do not have enough RAM, sorry.\n");
message(console, "%s", no_memory);
while (1) { sleep(1);}
}
}
}
/*
* 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];
/* Check if we are supposed to be in single user mode */
if (!strcmp(argv[1], "single") || !strcmp(argv[1], "-s") || !strcmp(argv[1], "1")) {
run_rc = FALSE;
tty0_commands = shell_commands;
tty1_commands = 0;
setproctitle("init [S]");
} else {
setproctitle("init [1]");
}
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
/* Make sure an init script exists before trying to run it */
if ( run_rc == TRUE && stat( INITSCRIPT, &statbuf)) {
tty0_commands = shell_commands;
tty1_commands = shell_commands;
}
/* Ok, now launch the rc script and/or prepare to
* start up some VTs 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 ( pid1 == 0 && *tty0_commands ) {
pid1 = run(tty0_commands, console, 1);
}
if ( pid2 == 0 && second_terminal && tty_commands[1] ) {
pid2 = run(tty_commands[1], arguments, second_terminal, 1);
if ( pid2 == 0 && *tty1_commands ) {
pid2 = run(tty1_commands, second_terminal, 1);
}
wpid = wait(&status);
if ( wpid > 0 && wpid != pid1) {
@ -467,6 +480,7 @@ init_main(int argc, char * * argv)
if ( wpid == pid2 ) {
pid2 = 0;
}
sleep(1);
}
}

630
init/init.c
View File

@ -41,144 +41,88 @@
#include <sys/vt.h> /* for vt_stat */
#include <sys/ioctl.h>
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;
#define DEBUG_INIT
static void
message(const char* terminal, const char * pattern, ...)
#define CONSOLE "/dev/console" /* Logical system console */
#define VT_PRIMARY "/dev/tty0" /* Virtual console master */
#define VT_SECONDARY "/dev/tty1" /* Virtual console master */
#define VT_LOG "/dev/tty2" /* Virtual console master */
#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"
static int maxproclen=0;
static char* argv0;
static char* console = CONSOLE;
static char* second_terminal = "/dev/tty2";
static char* log = "/dev/tty3";
/* try to open up the specified device */
int device_open(char* device, int mode)
{
int fd;
FILE * con = 0;
va_list arguments;
int m, f, fd = -1;
mode = m | 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;
/* Set original flags. */
if (m != mode)
fcntl(fd, F_SETFL, mode);
return fd;
}
/*
* 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) )
return;
va_start(arguments, pattern);
vfprintf(con, pattern, arguments);
/* print a message to the specified device */
void message(char* device, char *fmt, ...)
{
int fd;
va_list arguments;
if ((fd = device_open(device, O_WRONLY|O_NOCTTY|O_NDELAY)) >= 0) {
va_start(arguments, fmt);
vdprintf(fd, fmt, arguments);
va_end(arguments);
fclose(con);
}
close( fd);
}
static int
waitfor(int pid)
/* Set terminal settings to reasonable defaults */
void set_term()
{
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);
}
}
return wpid;
}
int fd;
struct termios tty;
static int
run(const char* program, const char* const* arguments,
const char* terminal, int get_enter)
{
static const char control_characters[] = {
'\003',
'\034',
'\177',
'\025',
'\004',
'\0',
'\1',
'\0',
'\021',
'\023',
'\032',
'\0',
'\022',
'\017',
'\027',
'\026',
'\0'
};
if ((fd = device_open(console, O_RDWR|O_NOCTTY)) < 0) {
message(log, "can't open %s", console);
return;
}
ioctl(fd, TCGETS, &tty);
tty.c_cflag &= CBAUD|CBAUDEX|CSIZE|CSTOPB|PARENB|PARODD;
tty.c_cflag |= HUPCL|CLOCAL;
static char * environment[] = {
"HOME=/",
"PATH=/bin:/sbin:/usr/bin:/usr/sbin",
"SHELL=/bin/sh",
0,
"USER=root",
0
};
tty.c_cc[VINTR] = 3;
tty.c_cc[VQUIT] = 28;
tty.c_cc[VERASE] = 127;
tty.c_cc[VKILL] = 24;
tty.c_cc[VEOF] = 4;
tty.c_cc[VTIME] = 0;
tty.c_cc[VMIN] = 1;
tty.c_cc[VSTART] = 17;
tty.c_cc[VSTOP] = 19;
tty.c_cc[VSUSP] = 26;
static const char press_enter[] =
"\nPlease press Enter to activate this console. ";
/* Set pre and post processing */
tty.c_iflag = IGNPAR|ICRNL|IXON|IXANY;
tty.c_oflag = OPOST|ONLCR;
tty.c_lflag = ISIG|ICANON|ECHO|ECHOCTL|ECHOPRT|ECHOKE;
int pid;
environment[3]=term_ptr;
pid = fork();
if ( pid == 0 ) {
struct termios t;
const char * const * arg;
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);
}
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 set the terminal line. */
ioctl(fd, TCSETS, &tty);
close( fd);
}
static int
@ -217,33 +161,168 @@ set_free_pages()
fclose(f);
}
static void
console_init()
{
int fd;
int tried_devcons = 0;
int tried_vtmaster = 0;
char *s;
if ((s = getenv("CONSOLE")) != NULL)
console = s;
else {
console = CONSOLE;
tried_devcons++;
}
while ((fd = open(console, O_RDONLY|O_NONBLOCK)) < 0) {
if (!tried_devcons) {
tried_devcons++;
console = CONSOLE;
continue;
}
if (!tried_vtmaster) {
tried_vtmaster++;
console = VT_PRIMARY;
continue;
}
break;
}
if (fd < 0)
console = "/dev/null";
else
close(fd);
}
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=%x.\n", wpid, status);
}
return wpid;
}
static int
run(const char* command, char* terminal, int get_enter)
{
int f, pid;
char *args[16];
char buf[256];
char* ptr;
static const char press_enter[] =
"\nPlease press Enter to activate this console. ";
/* Make a proper command from the command string */
strcpy(buf, command);
ptr = buf;
for(f = 1; f < 15; f++) {
/* Skip white space */
while(*ptr == ' ' || *ptr == '\t') ptr++;
args[f] = ptr;
/* May be trailing space.. */
if (*ptr == 0) break;
/* Skip this `word' */
while(*ptr && *ptr != ' ' && *ptr != '\t' && *ptr != '#')
ptr++;
/* If end-of-line, break */
if (*ptr == '#' || *ptr == 0) {
f++;
*ptr = 0;
break;
}
/* End word with \0 and continue */
args[f] = NULL;
}
args[0] = args[1];
if ((pid = fork()) == 0) {
/* Clean up */
close(0);
close(1);
close(2);
setsid();
if ((f = device_open(terminal, O_RDWR|O_NOCTTY)) < 0) {
message( log, "open(%s) failed: %s", terminal, strerror(errno));
return -1;
}
dup(f);
dup(f);
tcsetpgrp(0, getpgrp());
set_term();
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);
}
/* Log the process name and args */
message(log, "Executing '%s'\n", command);
/* Now run it. This should take over the PID, so nothing
* further in init.c should be run by this PID. */
execvp(args[1], args + 1);
/* If shell scripts are not executed, force the issue */
if (errno == ENOEXEC) {
char buf[256];
args[1] = SHELL;
args[2] = "-c";
strcpy(buf, "exec ");
strcat(buf, command);
args[3] = buf;
args[4] = NULL;
execvp(args[1], args + 1);
}
message(log, "Could not execute '%s'\n", command, strerror(errno));
exit(-1);
}
return pid;
}
#ifndef DEBUG_INIT
static void
shutdown_system(void)
{
static const char * const umount_args[] = {"/bin/umount", "-a", "-n", 0};
static const char * const swapoff_args[] = {"/bin/swapoff", "-a", 0};
message(console, "The system is going down NOW !!");
sync();
/* Allow Ctrl-Alt-Del to reboot system. */
reboot(RB_ENABLE_CAD);
message(console, "The system is going down NOW !!");
sync();
/* Allow Ctrl-Alt-Del to reboot system. */
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);
/* Send signals to every process _except_ pid 1 */
message(console, "Sending SIGHUP to all processes.\r\n");
kill(-1, SIGHUP);
sleep(2);
sync();
message(console, "Sending SIGKILL to all processes.\r\n");
kill(-1, SIGKILL);
sleep(1);
waitfor(run("/bin/swapoff -a", console, 0));
waitfor(run("/bin/umount -a -n", console, 0));
sync();
if (get_kernel_revision() <= 2*65536+2*256+11) {
/* Removed bdflush call, kupdate in kernels >2.2.11 */
bdflush(1, 0);
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));
sync();
if (get_kernel_revision() <= 2*65536+2*256+11) {
/* Removed bdflush call, kupdate in kernels >2.2.11 */
bdflush(1, 0);
sync();
}
}
}
static void
@ -251,7 +330,7 @@ halt_signal(int sig)
{
shutdown_system();
message(console, "The system is halted. Press CTRL-ALT-DEL or turn off power\r\n");
reboot( RB_HALT_SYSTEM);
reboot( RB_POWER_OFF);
exit(0);
}
@ -263,202 +342,136 @@ reboot_signal(int sig)
reboot( RB_AUTOBOOT);
exit(0);
}
static void
configure_terminals( int serial_cons, int single_user_mode )
{
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;
}
else
/* falls back to /dev/tty1 if an error occurs */
strcpy( console, default_console );
}
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;
}
int setproctitle(char *fmt, ...)
{
va_list ap;
int len;
char buf[256];
buf[0] = 0;
va_start(ap, fmt);
len = vsprintf(buf, fmt, ap);
va_end(ap);
memset(argv0, 0, maxproclen + 1);
strncpy(argv0, buf, maxproclen);
return len;
}
extern int
init_main(int argc, char * * argv)
{
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;
int run_rc = TRUE;
int pid1 = 0;
int pid2 = 0;
struct stat statbuf;
const char* init_commands = SHELL "-c exec " INITSCRIPT;
const char* shell_commands = SHELL;
const char* tty0_commands = init_commands;
const char* tty1_commands = shell_commands;
const char* no_memory =
"Sorry, your computer does not have enough memory.\n";
/*
* 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.
*/
/* For later use */
argv0 = argv[0];
maxproclen = strlen(argv[0]);
setproctitle("init [boot]");
#ifndef DEBUG_INIT
/* Set up sig handlers */
signal(SIGUSR1, halt_signal);
signal(SIGSEGV, halt_signal);
signal(SIGPWR, halt_signal);
signal(SIGALRM, halt_signal);
signal(SIGHUP, halt_signal);
signal(SIGUSR2, reboot_signal);
signal(SIGINT, reboot_signal);
signal(SIGTERM, reboot_signal);
#endif
/* Figure out where the default console should be */
console_init();
/* 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
/* Close whatever files are open, and reset the console. */
close(0);
close(1);
close(2);
set_term();
setsid();
signal(SIGUSR1, halt_signal);
signal(SIGUSR2, reboot_signal);
signal(SIGINT, reboot_signal);
signal(SIGTERM, reboot_signal);
/* Make sure PATH is set to something sane */
if (getenv("PATH") == NULL)
putenv(PATH_DEFAULT);
reboot(RB_DISABLE_CAD);
/* Hello world */
message(console, "%s started: BusyBox v%s (%s) multi-call binary",
argv[0], BB_VER, BB_BT);
message(log, "%s started: BusyBox v%s (%s) multi-call binary",
argv[0], BB_VER, BB_BT);
message(log, "%s: started. ", argv[0]);
for ( j = 1; j < argc; j++ ) {
if ( strcmp(argv[j], "single") == 0 ) {
run_rc = FALSE;
tty_commands[0] = "bin/sh";
tty_commands[1] = 0;
}
}
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;
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;
}
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];
}
}
printf("mounting /proc ...\n");
/* Mount /proc */
message(console, "Mounting /proc: \n");
if (mount("/proc","/proc","proc",0,0)) {
perror("mounting /proc failed\n");
message(log, "%s: could not mount /proc!\n", argv[0]);
message(console, "failed!\n");
}
printf("\tdone.\n");
message(console, "done.\n");
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;
}
/* Make sure /etc/init.d/rc exists */
retval= stat(tty_commands[0],&statbuf);
if (retval)
run_rc = FALSE;
configure_terminals( serial_console, run_rc);
/* Make sure there is enough memory to do something useful*/
set_free_pages();
/* not enough memory to do anything useful*/
if (mem_total() < 2000) {
int retval;
retval= stat("/etc/fstab",&statbuf);
if (retval) {
printf("You do not have enough RAM, sorry.\n");
message(console, "%s", no_memory);
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));
waitfor(run("/bin/swapon -a", console, 0));
if (mem_total() < 2000) {
printf("You do not have enough RAM, sorry.\n");
message(console, "%s", no_memory);
while (1) { sleep(1);}
}
}
}
/*
* 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];
/* Check if we are supposed to be in single user mode */
if (!strcmp(argv[1], "single") || !strcmp(argv[1], "-s") || !strcmp(argv[1], "1")) {
run_rc = FALSE;
tty0_commands = shell_commands;
tty1_commands = 0;
setproctitle("init [S]");
} else {
setproctitle("init [1]");
}
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
/* Make sure an init script exists before trying to run it */
if ( run_rc == TRUE && stat( INITSCRIPT, &statbuf)) {
tty0_commands = shell_commands;
tty1_commands = shell_commands;
}
/* Ok, now launch the rc script and/or prepare to
* start up some VTs 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 ( pid1 == 0 && *tty0_commands ) {
pid1 = run(tty0_commands, console, 1);
}
if ( pid2 == 0 && second_terminal && tty_commands[1] ) {
pid2 = run(tty_commands[1], arguments, second_terminal, 1);
if ( pid2 == 0 && *tty1_commands ) {
pid2 = run(tty1_commands, second_terminal, 1);
}
wpid = wait(&status);
if ( wpid > 0 && wpid != pid1) {
@ -467,6 +480,7 @@ init_main(int argc, char * * argv)
if ( wpid == pid2 ) {
pid2 = 0;
}
sleep(1);
}
}

5
internal.h
View File

@ -82,6 +82,8 @@ extern int loadfont_main(int argc, char** argv);
extern int loadkmap_main(int argc, char** argv);
extern int losetup_main(int argc, char** argv);
extern int ls_main(int argc, char** argv);
extern int chvt_main(int argc, char** argv);
extern int deallocvt_main(int argc, char** argv);
extern int makedevs_main(int argc, char** argv);
extern int math_main(int argc, char** argv);
extern int mkdir_main(int argc, char** argv);
@ -110,6 +112,7 @@ extern int true_main(int argc, char** argv);
extern int tryopen_main(int argc, char** argv);
extern int umount_main(int argc, char** argv);
extern int update_main(int argc, char** argv);
extern int uname_main(int argc, char** argv);
extern int zcat_main(int argc, char** argv);
extern int gzip_main(int argc, char** argv);
@ -141,7 +144,7 @@ extern gid_t my_getgrnam(char *name);
extern void my_getpwuid(char* name, uid_t uid);
extern void my_getgrgid(char* group, gid_t gid);
extern int get_kernel_revision();
extern int get_console_fd(char* tty_name);
#if defined (BB_FSCK_MINIX) || defined (BB_MKFS_MINIX)

92
utility.c
View File

@ -720,5 +720,97 @@ extern int find_match(char *haystack, char *needle, int ignoreCase)
}
#endif
#if (defined BB_CHVT) || (defined BB_DEALLOCVT)
#include <linux/kd.h>
#include <sys/ioctl.h>
int is_a_console(int fd)
{
char arg;
arg = 0;
return (ioctl(fd, KDGKBTYPE, &arg) == 0
&& ((arg == KB_101) || (arg == KB_84)));
}
static int open_a_console(char *fnam)
{
int fd;
/* try read-only */
fd = open(fnam, O_RDWR);
/* if failed, try read-only */
if (fd < 0 && errno == EACCES)
fd = open(fnam, O_RDONLY);
/* if failed, try write-only */
if (fd < 0 && errno == EACCES)
fd = open(fnam, O_WRONLY);
/* if failed, fail */
if (fd < 0)
return -1;
/* if not a console, fail */
if (! is_a_console(fd))
{
close(fd);
return -1;
}
/* success */
return fd;
}
/*
* Get an fd for use with kbd/console ioctls.
* We try several things because opening /dev/console will fail
* if someone else used X (which does a chown on /dev/console).
*
* if tty_name is non-NULL, try this one instead.
*/
int get_console_fd(char* tty_name)
{
int fd;
if (tty_name)
{
if (-1 == (fd = open_a_console(tty_name)))
return -1;
else
return fd;
}
fd = open_a_console("/dev/tty");
if (fd >= 0)
return fd;
fd = open_a_console("/dev/tty0");
if (fd >= 0)
return fd;
fd = open_a_console("/dev/console");
if (fd >= 0)
return fd;
for (fd = 0; fd < 3; fd++)
if (is_a_console(fd))
return fd;
fprintf(stderr,
"Couldnt get a file descriptor referring to the console\n");
return -1; /* total failure */
}
#endif
/* END CODE */