int do_sigaction(int sig, struct sigaction *sa, struct sigaction *old_sa){
if (sig<1 || sig>NSIG || sig==SIGKILL || sa==NULL) {
syserr(EINVAL);
return -1;
}
// store the old struct sigaction
if (old_sa!=NULL) {
if (vm_verify(old_sa, sizeof(struct sigaction))<0) {
syserr(EFAULT);
return -1;
}
*old_sa = cu->p_sigact[sig-1];
}
// set the new sigaction
if (vm_verify(sa, sizeof(struct sigaction))<0) {
syserr(EFAULT);
return -1;
}
cu->p_sigact[sig-1] = *sa;
cu->p_sigact[sig-1].sa_mask |= (1<<(sig-1));
return 0;
}
/*
* The value of pid can be: (via `man waitpid`)
* < -1 wait for any child process whose process group ID is equal to the absolute value of pid.
* -1 wait for any child process.
* 0 wait for any child process whose process group ID is equal to that of the calling process.
* > 0 wait for the child whose process ID is equal to the value of pid.
*
* opt:
* WNOHANG : return immediately if no child exited.
*
*/
int do_waitpid(int pid, int *stat, int opt){
struct proc *p;
uint nr;
if (vm_verify(stat, sizeof(int)) < 0){
syserr(EFAULT);
return -1;
}
//
_repeat:
for(nr=1; nr<NPROC; nr++){
if ((p=proc[nr]) && p!=cu) {
if (pid < -1) {
if (p->p_ppid!=cu->p_pid || p->p_pgrp!=cu->p_pid)
continue;
}
else if (pid == -1) {
if (p->p_ppid!=cu->p_pid)
continue;
}
else if (pid == 0) {
if (p->p_ppid!=cu->p_pid || p->p_pgrp!=cu->p_pgrp)
continue;
}
else if (pid > 0) {
if (p->p_ppid!=cu->p_pid || p->p_pid!=pid)
continue;
}
// on found
switch(p->p_stat){
case SZOMB:
*stat = p->p_ret;
pid = p->p_pid;
proc[pid] = NULL;
kfree(p, PAGE);
return pid;
default:
continue;
}
}
}
_not_found:
// no child has found
if (opt & WNOHANG) {
return 0;
}
sleep(cu, PWAIT);
goto _repeat;
}
long sys_readdir(unsigned int fd, struct dirent *dirent, unsigned int count)
{
struct file *file;
struct inode *inode;
if (vm_verify(¤t->mm, dirent, sizeof(*dirent), VM_WRITE))
return -EFAULT;
if (fd >= NR_FILES || !(file = current->filp[fd]) ||
!(inode = file->f_inode))
return -EBADF;
if (file->f_op && file->f_op->readdir)
return file->f_op->readdir(inode, file, dirent, count);
return -ENOTDIR;
}
long sys_stat(const char *pathname, size_t name_len, struct stat *s)
{
int error;
struct inode *inode;
error = verify_user_string(pathname, name_len);
if (error)
return error;
if (vm_verify(¤t->mm, s, sizeof(*s), VM_WRITE))
return -EFAULT;
error = namei(pathname, &inode);
if (error)
return error;
do_stat(inode, s);
iput(inode);
return 0;
}
