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-rw-r--r--init.c438
1 files changed, 438 insertions, 0 deletions
diff --git a/init.c b/init.c
new file mode 100644
index 0000000..4771722
--- /dev/null
+++ b/init.c
@@ -0,0 +1,438 @@
+#include "internal.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <unistd.h>
+#include <errno.h>
+#include <signal.h>
+#include <termios.h>
+#include <sys/types.h>
+#include <sys/fcntl.h>
+#include <sys/wait.h>
+#include <string.h>
+#include <sys/mount.h>
+#include <sys/reboot.h>
+#include <sys/kdaemon.h>
+#include <sys/swap.h>
+#include <sys/sysmacros.h>
+
+const char init_usage[] = "Used internally by the system.";
+char console[16] = "";
+const char * default_console = "/dev/tty1";
+char * first_terminal = NULL;
+const char * second_terminal = "/dev/tty2";
+const char log[] = "/dev/tty3";
+char * term_ptr = NULL;
+
+static void
+message(const char * terminal, const char * pattern, ...)
+{
+ int fd;
+ FILE * con = 0;
+ va_list arguments;
+
+ /*
+ * 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 ( ((fd = open(terminal, O_WRONLY|O_NOCTTY)) < 0)
+ || ((con = fdopen(fd, "w")) == NULL) )
+ return;
+
+ va_start(arguments, pattern);
+ vfprintf(con, pattern, arguments);
+ va_end(arguments);
+ fclose(con);
+}
+
+static int
+waitfor(int pid)
+{
+ 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;
+}
+
+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'
+ };
+
+ static char * environment[] = {
+ "HOME=/",
+ "PATH=/bin:/sbin:/usr/bin:/usr/sbin",
+ "SHELL=/bin/sh",
+ 0,
+ "USER=root",
+ 0
+ };
+
+ static const char press_enter[] =
+ "Please press Enter to activate this console. ";
+
+ 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 the installation system.
+ */
+ 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;
+}
+
+static int
+mem_total()
+{
+ 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)));
+ }
+ }
+ return -1;
+}
+
+static void
+set_free_pages()
+{
+ 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);
+}
+
+static void
+shutdown_system(int do_reboot)
+{
+ static const char * const umount_args[] = {"/bin/umount", "-a", "-n", 0};
+
+ 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);
+ sync();
+ message(console, "Sending SIGKILL to all processes.\r\n");
+ kill(-1, SIGKILL);
+ sleep(1);
+ waitfor(run("/bin/umount", umount_args, console, 0));
+ sync();
+ bdflush(1, 0);
+ sync();
+ reboot(do_reboot ?RB_AUTOBOOT : RB_HALT_SYSTEM);
+ exit(0);
+}
+
+static void
+halt_signal(int sig)
+{
+ shutdown_system(0);
+}
+
+static void
+reboot_signal(int sig)
+{
+ shutdown_system(1);
+}
+
+static void
+exit_signal(int sig)
+{
+
+ /* initrd doesn't work anyway */
+
+ shutdown_system(1);
+
+ /* This is used on the initial ramdisk */
+
+ /* message(log, "Init exiting.");
+ exit(0);
+ */
+}
+
+void
+configure_terminals( int serial_cons );
+
+extern int
+init_main(struct FileInfo * i, int argc, char * * argv)
+{
+ static const char * const rc = "etc/rc";
+ const char * arguments[100];
+ int run_rc = 1;
+ int j;
+ int pid1 = 0;
+ int pid2 = 0;
+ int create_swap= -1;
+ struct stat statbuf;
+#ifndef INCLUDE_DINSTALL
+ const char * tty_commands[2] = { "bin/sh", "bin/sh"};
+#else
+ const char * tty_commands[2] = { "sbin/dinstall", "bin/sh"};
+#endif
+ char swap[20];
+ int serial_console = 0;
+
+ /*
+ * 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();
+
+ signal(SIGUSR1, halt_signal);
+ signal(SIGUSR2, reboot_signal);
+ signal(SIGINT, reboot_signal);
+ signal(SIGTERM, exit_signal);
+
+ reboot(RB_DISABLE_CAD);
+
+ message(log, "%s: started. ", argv[0]);
+
+ for ( j = 1; j < argc; j++ ) {
+ if ( strcmp(argv[j], "single") == 0 ) {
+ run_rc = 0;
+ 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];
+ }
+ }
+ configure_terminals( serial_console );
+
+ printf("mounting /proc ...\n");
+ if (mount("/proc","/proc","proc",0,0)) {
+ perror("mounting /proc failed\n");
+ }
+ printf("\tdone.\n");
+
+ set_free_pages();
+
+ if (mem_total() < 3500) { /* not enough memory for standard install */
+ int retval;
+ retval= stat("/etc/swappartition",&statbuf);
+ if (retval) {
+ printf("
+You do not have enough RAM, hence you must boot using the Boot Disk
+for Low Memory systems.
+
+Read the instructions in the install.html file.
+");
+ while (1) {;}
+ } else { /* everything OK */
+ FILE *f;
+
+ f=fopen("/etc/swappartition","r");
+ fgets(swap,19,f);
+ fclose(f);
+ *(strstr(swap,"\n"))='\0';
+
+ if (swapon(swap,0)) {
+ perror("swapon failed\n");
+ } else {
+ f=fopen("/etc/swaps","w");
+ fprintf(f,"%s none swap rw 0 0",swap);
+ fclose(f);
+ create_swap = 0;
+ }
+ }
+ }
+
+ /*
+ * Don't modify **argv directly, it would show up in the "ps" display.
+ * I don't want "init" to look like "rc".
+ */
+ arguments[0] = rc;
+ for ( j = 1; j < argc; j++ ) {
+ arguments[j] = argv[j];
+ }
+ arguments[j] = 0;
+
+ if ( run_rc )
+ waitfor(run(rc, arguments, console, 0));
+
+ if ( 0 == create_swap) {
+ if (unlink("/etc/swappartition")) {
+ perror("unlinking /etc/swappartition");
+ }
+ }
+
+ arguments[0] = "-sh";
+ arguments[1] = 0;
+ for ( ; ; ) {
+ int wpid;
+ int status;
+
+ if ( pid1 == 0 && tty_commands[0] ) {
+ /* Ask before starting a shell */
+ /*
+ arguments[0] = tty_commands[0];
+ */
+ pid1 = run(tty_commands[0], arguments, first_terminal, 0);
+ }
+ if ( pid2 == 0 && tty_commands[1] )
+ pid2 = run(tty_commands[1], arguments, second_terminal, 1);
+ wpid = wait(&status);
+ if ( wpid > 0 ) {
+ /* DEBUGGING */
+ message(log, "pid %d exited, status=%x.\n", wpid, status);
+ }
+ if ( wpid == pid1 ) {
+ pid1 = 0;
+ }
+ if ( wpid == pid2 )
+ pid2 = 0;
+ }
+}
+
+void
+configure_terminals( int serial_cons )
+{
+ //struct stat statbuf;
+ char *tty;
+
+ switch (serial_cons) {
+ case 1:
+ strcpy( console, "/dev/ttyS0" );
+ break;
+ case 2:
+ strcpy( console, "/dev/ttyS1" );
+ break;
+ default:
+ tty = ttyname(0);
+ if (tty) {
+ strcpy( console, tty );
+ if (!strncmp( tty, "/dev/ttyS", 9 ))
+ serial_cons=1;
+ }
+ else
+ /* falls back to /dev/tty1 if an error occurs */
+ strcpy( console, default_console );
+ }
+ if (!first_terminal)
+ first_terminal = console;
+ if (serial_cons && !strncmp(term_ptr,"TERM=linux",10))
+ term_ptr = "TERM=vt100";
+}