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/*
* Copyright (C) 2002 Jeff Dike (jdike@addtoit.com)
* Licensed under the GPL
*/
#include <unistd.h>
#include <stdio.h>
#include <errno.h>
#include <signal.h>
#include <setjmp.h>
#include <linux/unistd.h>
#include <sys/mman.h>
#include <sys/wait.h>
#include "ptrace_user.h"
#include "os.h"
#include "user.h"
#include "user_util.h"
#include "process.h"
#include "irq_user.h"
#include "kern_util.h"
#include "longjmp.h"
#include "skas_ptrace.h"
#define ARBITRARY_ADDR -1
#define FAILURE_PID -1
#define STAT_PATH_LEN sizeof("/proc/#######/stat\0")
#define COMM_SCANF "%*[^)])"
unsigned long os_process_pc(int pid)
{
char proc_stat[STAT_PATH_LEN], buf[256];
unsigned long pc;
int fd, err;
sprintf(proc_stat, "/proc/%d/stat", pid);
fd = os_open_file(proc_stat, of_read(OPENFLAGS()), 0);
if(fd < 0){
printk("os_process_pc - couldn't open '%s', err = %d\n",
proc_stat, -fd);
return(ARBITRARY_ADDR);
}
err = os_read_file(fd, buf, sizeof(buf));
if(err < 0){
printk("os_process_pc - couldn't read '%s', err = %d\n",
proc_stat, -err);
os_close_file(fd);
return(ARBITRARY_ADDR);
}
os_close_file(fd);
pc = ARBITRARY_ADDR;
if(sscanf(buf, "%*d " COMM_SCANF " %*c %*d %*d %*d %*d %*d %*d %*d "
"%*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d "
"%*d %*d %*d %*d %*d %lu", &pc) != 1){
printk("os_process_pc - couldn't find pc in '%s'\n", buf);
}
return(pc);
}
int os_process_parent(int pid)
{
char stat[STAT_PATH_LEN];
char data[256];
int parent, n, fd;
if(pid == -1) return(-1);
snprintf(stat, sizeof(stat), "/proc/%d/stat", pid);
fd = os_open_file(stat, of_read(OPENFLAGS()), 0);
if(fd < 0){
printk("Couldn't open '%s', err = %d\n", stat, -fd);
return(FAILURE_PID);
}
n = os_read_file(fd, data, sizeof(data));
os_close_file(fd);
if(n < 0){
printk("Couldn't read '%s', err = %d\n", stat, -n);
return(FAILURE_PID);
}
parent = FAILURE_PID;
n = sscanf(data, "%*d " COMM_SCANF " %*c %d", &parent);
if(n != 1)
printk("Failed to scan '%s'\n", data);
return(parent);
}
void os_stop_process(int pid)
{
kill(pid, SIGSTOP);
}
void os_kill_process(int pid, int reap_child)
{
kill(pid, SIGKILL);
if(reap_child)
CATCH_EINTR(waitpid(pid, NULL, 0));
}
/* This is here uniquely to have access to the userspace errno, i.e. the one
* used by ptrace in case of error.
*/
long os_ptrace_ldt(long pid, long addr, long data)
{
int ret;
ret = ptrace(PTRACE_LDT, pid, addr, data);
if (ret < 0)
return -errno;
return ret;
}
/* Kill off a ptraced child by all means available. kill it normally first,
* then PTRACE_KILL it, then PTRACE_CONT it in case it's in a run state from
* which it can't exit directly.
*/
void os_kill_ptraced_process(int pid, int reap_child)
{
kill(pid, SIGKILL);
ptrace(PTRACE_KILL, pid);
ptrace(PTRACE_CONT, pid);
if(reap_child)
CATCH_EINTR(waitpid(pid, NULL, 0));
}
void os_usr1_process(int pid)
{
kill(pid, SIGUSR1);
}
/* Don't use the glibc version, which caches the result in TLS. It misses some
* syscalls, and also breaks with clone(), which does not unshare the TLS.
*/
inline _syscall0(pid_t, getpid)
int os_getpid(void)
{
return(getpid());
}
int os_getpgrp(void)
{
return getpgrp();
}
int os_map_memory(void *virt, int fd, unsigned long long off, unsigned long len,
int r, int w, int x)
{
void *loc;
int prot;
prot = (r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) |
(x ? PROT_EXEC : 0);
loc = mmap64((void *) virt, len, prot, MAP_SHARED | MAP_FIXED,
fd, off);
if(loc == MAP_FAILED)
return(-errno);
return(0);
}
int os_protect_memory(void *addr, unsigned long len, int r, int w, int x)
{
int prot = ((r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) |
(x ? PROT_EXEC : 0));
if(mprotect(addr, len, prot) < 0)
return(-errno);
return(0);
}
int os_unmap_memory(void *addr, int len)
{
int err;
err = munmap(addr, len);
if(err < 0)
return(-errno);
return(0);
}
void init_new_thread_stack(void *sig_stack, void (*usr1_handler)(int))
{
int flags = 0, pages;
if(sig_stack != NULL){
pages = (1 << UML_CONFIG_KERNEL_STACK_ORDER);
set_sigstack(sig_stack, pages * page_size());
flags = SA_ONSTACK;
}
if(usr1_handler) set_handler(SIGUSR1, usr1_handler, flags, -1);
}
void init_new_thread_signals(int altstack)
{
int flags = altstack ? SA_ONSTACK : 0;
set_handler(SIGSEGV, (__sighandler_t) sig_handler, flags,
SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
set_handler(SIGTRAP, (__sighandler_t) sig_handler, flags,
SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
set_handler(SIGFPE, (__sighandler_t) sig_handler, flags,
SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
set_handler(SIGILL, (__sighandler_t) sig_handler, flags,
SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
set_handler(SIGBUS, (__sighandler_t) sig_handler, flags,
SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
set_handler(SIGUSR2, (__sighandler_t) sig_handler,
flags, SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
signal(SIGHUP, SIG_IGN);
init_irq_signals(altstack);
}
int run_kernel_thread(int (*fn)(void *), void *arg, void **jmp_ptr)
{
sigjmp_buf buf;
int n, enable;
*jmp_ptr = &buf;
n = UML_SIGSETJMP(&buf, enable);
if(n != 0)
return(n);
(*fn)(arg);
return(0);
}
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