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#include <errno.h>
#include <signal.h>
#include <sys/wait.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/tty.h>
#include <asm/segment.h>
int sys_pause(void);
int sys_close(int fd);
void release(struct task_struct * p)
{
int i;
if (!p)
return;
for (i=1 ; i<NR_TASKS ; i++)
if (task[i]==p) {
task[i]=NULL;
free_page((long)p);
schedule();
return;
}
panic("trying to release non-existent task");
}
static inline void send_sig(long sig,struct task_struct * p,int priv)
{
if (!p || sig<1 || sig>32)
return;
if (priv ||
current->uid==p->uid ||
current->euid==p->uid ||
current->uid==p->euid ||
current->euid==p->euid)
p->signal |= (1<<(sig-1));
}
void do_kill(long pid,long sig,int priv)
{
struct task_struct **p = NR_TASKS + task;
if (!pid) while (--p > &FIRST_TASK) {
if (*p && (*p)->pgrp == current->pid)
send_sig(sig,*p,priv);
} else if (pid>0) while (--p > &FIRST_TASK) {
if (*p && (*p)->pid == pid)
send_sig(sig,*p,priv);
} else if (pid == -1) while (--p > &FIRST_TASK)
send_sig(sig,*p,priv);
else while (--p > &FIRST_TASK)
if (*p && (*p)->pgrp == -pid)
send_sig(sig,*p,priv);
}
int sys_kill(int pid,int sig)
{
do_kill(pid,sig,!(current->uid || current->euid));
return 0;
}
int do_exit(long code)
{
int i;
free_page_tables(get_base(current->ldt[1]),get_limit(0x0f));
free_page_tables(get_base(current->ldt[2]),get_limit(0x17));
for (i=0 ; i<NR_TASKS ; i++)
if (task[i] && task[i]->father == current->pid)
task[i]->father = 0;
for (i=0 ; i<NR_OPEN ; i++)
if (current->filp[i])
sys_close(i);
iput(current->pwd);
current->pwd=NULL;
iput(current->root);
current->root=NULL;
if (current->leader && current->tty >= 0)
tty_table[current->tty].pgrp = 0;
if (last_task_used_math == current)
last_task_used_math = NULL;
if (current->father) {
current->state = TASK_ZOMBIE;
do_kill(current->father,SIGCHLD,1);
current->exit_code = code;
} else
release(current);
schedule();
return (-1); /* just to suppress warnings */
}
int sys_exit(int error_code)
{
return do_exit((error_code&0xff)<<8);
}
int sys_waitpid(pid_t pid,int * stat_addr, int options)
{
int flag=0;
struct task_struct ** p;
verify_area(stat_addr,4);
repeat:
for(p = &LAST_TASK ; p > &FIRST_TASK ; --p)
if (*p && *p != current &&
(pid==-1 || (*p)->pid==pid ||
(pid==0 && (*p)->pgrp==current->pgrp) ||
(pid<0 && (*p)->pgrp==-pid)))
if ((*p)->father == current->pid) {
flag=1;
if ((*p)->state==TASK_ZOMBIE) {
put_fs_long((*p)->exit_code,
(unsigned long *) stat_addr);
current->cutime += (*p)->utime;
current->cstime += (*p)->stime;
flag = (*p)->pid;
release(*p);
return flag;
}
}
if (flag) {
if (options & WNOHANG)
return 0;
sys_pause();
if (!(current->signal &= ~(1<<(SIGCHLD-1))))
goto repeat;
else
return -EINTR;
}
return -ECHILD;
}
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