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/*
* Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
* Licensed under the GPL
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <limits.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/utsname.h>
#include <sys/param.h>
#include <sys/time.h>
#include "asm/types.h"
#include <ctype.h>
#include <signal.h>
#include <wait.h>
#include <errno.h>
#include <stdarg.h>
#include <sched.h>
#include <termios.h>
#include <string.h>
#include "kern_util.h"
#include "user.h"
#include "mem_user.h"
#include "init.h"
#include "ptrace_user.h"
#include "uml-config.h"
#include "os.h"
#include "longjmp.h"
#include "kern_constants.h"
void stack_protections(unsigned long address)
{
if(mprotect((void *) address, UM_THREAD_SIZE,
PROT_READ | PROT_WRITE | PROT_EXEC) < 0)
panic("protecting stack failed, errno = %d", errno);
}
int raw(int fd)
{
struct termios tt;
int err;
CATCH_EINTR(err = tcgetattr(fd, &tt));
if(err < 0)
return -errno;
cfmakeraw(&tt);
CATCH_EINTR(err = tcsetattr(fd, TCSADRAIN, &tt));
if(err < 0)
return -errno;
/* XXX tcsetattr could have applied only some changes
* (and cfmakeraw() is a set of changes) */
return 0;
}
void setup_machinename(char *machine_out)
{
struct utsname host;
uname(&host);
#ifdef UML_CONFIG_UML_X86
# ifndef UML_CONFIG_64BIT
if (!strcmp(host.machine, "x86_64")) {
strcpy(machine_out, "i686");
return;
}
# else
if (!strcmp(host.machine, "i686")) {
strcpy(machine_out, "x86_64");
return;
}
# endif
#endif
strcpy(machine_out, host.machine);
}
void setup_hostinfo(char *buf, int len)
{
struct utsname host;
uname(&host);
snprintf(buf, len, "%s %s %s %s %s", host.sysname, host.nodename,
host.release, host.version, host.machine);
}
int setjmp_wrapper(void (*proc)(void *, void *), ...)
{
va_list args;
jmp_buf buf;
int n;
n = UML_SETJMP(&buf);
if(n == 0){
va_start(args, proc);
(*proc)(&buf, &args);
}
va_end(args);
return n;
}
void os_dump_core(void)
{
int pid;
signal(SIGSEGV, SIG_DFL);
/*
* We are about to SIGTERM this entire process group to ensure that
* nothing is around to run after the kernel exits. The
* kernel wants to abort, not die through SIGTERM, so we
* ignore it here.
*/
signal(SIGTERM, SIG_IGN);
kill(0, SIGTERM);
/*
* Most of the other processes associated with this UML are
* likely sTopped, so give them a SIGCONT so they see the
* SIGTERM.
*/
kill(0, SIGCONT);
/*
* Now, having sent signals to everyone but us, make sure they
* die by ptrace. Processes can survive what's been done to
* them so far - the mechanism I understand is receiving a
* SIGSEGV and segfaulting immediately upon return. There is
* always a SIGSEGV pending, and (I'm guessing) signals are
* processed in numeric order so the SIGTERM (signal 15 vs
* SIGSEGV being signal 11) is never handled.
*
* Run a waitpid loop until we get some kind of error.
* Hopefully, it's ECHILD, but there's not a lot we can do if
* it's something else. Tell os_kill_ptraced_process not to
* wait for the child to report its death because there's
* nothing reasonable to do if that fails.
*/
while ((pid = waitpid(-1, NULL, WNOHANG)) > 0)
os_kill_ptraced_process(pid, 0);
abort();
}
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