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/*
* linux/kernel/sys.c
*
* (C) 1991 Linus Torvalds
*/
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <sys/stat.h>
#include <errno.h>
#include <linux/sched.h>
#include <linux/tty.h>
#include <linux/kernel.h>
#include <asm/segment.h>
#include <sys/times.h>
#include <sys/utsname.h>
//ADD FOR getcwd
struct linux_dirent {
long d_ino;
off_t d_off;
unsigned short d_reclen;
char d_name[];
};
long sys_getcwd(char *buf,size_t size)
{
int block=current->pwd->i_zone[0];
int idev=current->pwd->i_dev;
int flag=0;
struct buffer_head * bh;
struct dir_entry * de;
struct m_inode *dir=current->pwd,*rdir=current->root;
if(dir==rdir)
{
flag=1;
goto mytag;
}
unsigned short curinode,finode,tempfi;
char name[128],base[128];
int entries,i;
if (!(block = current->pwd->i_zone[0]))
return NULL;
if (!(bh = bread(current->pwd->i_dev,block)))
return NULL;
de = (struct dir_entry *) bh->b_data;
curinode=de->inode;
de++;
finode=de->inode;
while (rdir!=dir)
{
//update father
dir=iget(idev,finode);
if (!(block = dir->i_zone[0]))
return NULL;
if (!(bh = bread(dir->i_dev,block)))
return NULL;
i = 0;
entries = dir->i_size / (sizeof (struct dir_entry));
de = (struct dir_entry *) bh->b_data;
tempfi=(de+1)->inode;
while (i < entries) {
if ((char *)de >= BLOCK_SIZE+bh->b_data) {
brelse(bh);
bh = NULL;
if (!(block = bmap(dir,i/DIR_ENTRIES_PER_BLOCK)) ||
!(bh = bread(dir->i_dev,block))) {
i += DIR_ENTRIES_PER_BLOCK;
continue;
}
de = (struct dir_entry *) bh->b_data;
}
if(de->inode==curinode)
{
memset(base,'\0',sizeof(base));
strcat(base,"/");
strcat(base,de->name);
strcat(base,name);
strcpy(name,base);
break;
}
de++;
i++;
}
curinode=finode;
finode=tempfi;
}
mytag:
if(flag) strcpy(name,"/");
size_t len=strlen(name);
if(size<len && buf!=NULL)
{
errno=ERANGE;
return NULL;
}
if(!buf)
buf=(char*)malloc(len);
char *p1=buf;
char *p2=name;
while(len--)
put_fs_byte(*(p2++),p1++);
return buf;
}
//THE END
int sys_getdents(unsigned int fd,struct linux_dirent *dirp,unsigned int count)
{
struct m_inode *filenode =current->filp[fd]->f_inode;
int block,i,entries,sizdir=sizeof(struct dir_entry);
struct buffer_head * bh;
struct dir_entry * de;
struct linux_dirent *initmp,*temp;
if(!(temp=(struct linux_dirent *)malloc(count+64)))
return -1;
initmp=temp;
int size=sizeof(long)+sizeof(off_t)+sizeof(unsigned short);
if (!(block = filenode->i_zone[0]))
return -1;
if (!(bh = bread(filenode->i_dev,block)))
return -1;
de = (struct dir_entry *) bh->b_data;
entries=filenode->i_size/(sizeof(struct dir_entry));
i=0;
int nread=0,pos=0;
while(i<entries)
{
if ((char *)de >= BLOCK_SIZE+bh->b_data) {
brelse(bh);
bh = NULL;
if (!(block = bmap(filenode,i/DIR_ENTRIES_PER_BLOCK)) ||
!(bh = bread(filenode->i_dev,block))) {
i += DIR_ENTRIES_PER_BLOCK;
continue;
}
pos+=((char*) bh->b_data-(char*)(de-1));
de = (struct dir_entry *) bh->b_data;
}
temp->d_ino=de->inode;
temp->d_off=pos;
strcpy(temp->d_name,de->name);
temp->d_reclen=size+strlen(de->name)+1;
nread+=temp->d_reclen;
temp=(struct linux_dirent*)((char*)temp+temp->d_reclen);
de++;
pos+=sizdir;
i++;
}
if(count<nread)
{
errno=ERANGE;
return -1;
}//printk("%d",nread);
i=nread;
char *p1=dirp;
char *p2=initmp;
while(i--)
put_fs_byte(*(p2++),p1++);
free(initmp);
return nread;
}
int sys_pipe2()
{
return -1;
}
unsigned int sys_sleep(unsigned int seconds)
{
struct sigaction tmp;
tmp.sa_handler = (void (*)(int)) SIG_IGN;
tmp.sa_mask = 0;
tmp.sa_flags = SA_ONESHOT | SA_NOMASK;
tmp.sa_restorer = (void (*)(void)) NULL;
current->sigaction[SIGALRM-1] = tmp;
current->alarm=(seconds>0)?(jiffies+HZ*seconds):0;
current->state=TASK_INTERRUPTIBLE;
current->counter=(current->counter>>1)+current->priority;
schedule();
return 0;
}
int sys_mmap()
{
return -1;
}
int sys_munmap()
{
return -1;
}
int sys_clone()
{
return -1;
}
int sys_ftime()
{
return -ENOSYS;
}
int sys_break()
{
return -ENOSYS;
}
int sys_ptrace()
{
return -ENOSYS;
}
int sys_stty()
{
return -ENOSYS;
}
int sys_gtty()
{
return -ENOSYS;
}
int sys_rename()
{
return -ENOSYS;
}
int sys_prof()
{
return -ENOSYS;
}
int sys_setregid(int rgid, int egid)
{
if (rgid>0) {
if ((current->gid == rgid) ||
suser())
current->gid = rgid;
else
return(-EPERM);
}
if (egid>0) {
if ((current->gid == egid) ||
(current->egid == egid) ||
suser()) {
current->egid = egid;
current->sgid = egid;
} else
return(-EPERM);
}
return 0;
}
int sys_setgid(int gid)
{
/* return(sys_setregid(gid, gid)); */
if (suser())
current->gid = current->egid = current->sgid = gid;
else if ((gid == current->gid) || (gid == current->sgid))
current->egid = gid;
else
return -EPERM;
return 0;
}
int sys_acct()
{
return -ENOSYS;
}
int sys_phys()
{
return -ENOSYS;
}
int sys_lock()
{
return -ENOSYS;
}
int sys_mpx()
{
return -ENOSYS;
}
int sys_ulimit()
{
return -ENOSYS;
}
int sys_time(long * tloc)
{
int i;
i = CURRENT_TIME;
if (tloc) {
verify_area(tloc,4);
put_fs_long(i,(unsigned long *)tloc);
}
return i;
}
/*
* Unprivileged users may change the real user id to the effective uid
* or vice versa.
*/
int sys_setreuid(int ruid, int euid)
{
int old_ruid = current->uid;
if (ruid>0) {
if ((current->euid==ruid) ||
(old_ruid == ruid) ||
suser())
current->uid = ruid;
else
return(-EPERM);
}
if (euid>0) {
if ((old_ruid == euid) ||
(current->euid == euid) ||
suser()) {
current->euid = euid;
current->suid = euid;
} else {
current->uid = old_ruid;
return(-EPERM);
}
}
return 0;
}
int sys_setuid(int uid)
{
/* return(sys_setreuid(uid, uid)); */
if (suser())
current->uid = current->euid = current->suid = uid;
else if ((uid == current->uid) || (uid == current->suid))
current->euid = uid;
else
return -EPERM;
return(0);
}
int sys_stime(long * tptr)
{
if (!suser())
return -EPERM;
startup_time = get_fs_long((unsigned long *)tptr) - jiffies/HZ;
return 0;
}
int sys_times(struct tms * tbuf)
{
if (tbuf) {
verify_area(tbuf,sizeof *tbuf);
put_fs_long(current->utime,(unsigned long *)&tbuf->tms_utime);
put_fs_long(current->stime,(unsigned long *)&tbuf->tms_stime);
put_fs_long(current->cutime,(unsigned long *)&tbuf->tms_cutime);
put_fs_long(current->cstime,(unsigned long *)&tbuf->tms_cstime);
}
return jiffies;
}
int sys_brk(unsigned long end_data_seg)
{
if (end_data_seg >= current->end_code &&
end_data_seg < current->start_stack - 16384)
current->brk = end_data_seg;
return current->brk;
}
/*
* This needs some heave checking ...
* I just haven't get the stomach for it. I also don't fully
* understand sessions/pgrp etc. Let somebody who does explain it.
*/
int sys_setpgid(int pid, int pgid)
{
int i;
if (!pid)
pid = current->pid;
if (!pgid)
pgid = current->pid;
for (i=0 ; i<NR_TASKS ; i++)
if (task[i] && task[i]->pid==pid) {
if (task[i]->leader)
return -EPERM;
if (task[i]->session != current->session)
return -EPERM;
task[i]->pgrp = pgid;
return 0;
}
return -ESRCH;
}
int sys_getpgrp(void)
{
return current->pgrp;
}
int sys_setsid(void)
{
if (current->leader && !suser())
return -EPERM;
current->leader = 1;
current->session = current->pgrp = current->pid;
current->tty = -1;
return current->pgrp;
}
int sys_getgroups()
{
return -ENOSYS;
}
int sys_setgroups()
{
return -ENOSYS;
}
int sys_uname(struct utsname * name)
{
static struct utsname thisname = {
"linux .0","nodename","release ","version ","machine "
};
int i;
if (!name) return -ERROR;
verify_area(name,sizeof *name);
for(i=0;i<sizeof *name;i++)
put_fs_byte(((char *) &thisname)[i],i+(char *) name);
return 0;
}
int sys_sethostname()
{
return -ENOSYS;
}
int sys_getrlimit()
{
return -ENOSYS;
}
int sys_setrlimit()
{
return -ENOSYS;
}
int sys_getrusage()
{
return -ENOSYS;
}
int sys_gettimeofday()
{
return -ENOSYS;
}
int sys_settimeofday()
{
return -ENOSYS;
}
int sys_umask(int mask)
{
int old = current->umask;
current->umask = mask & 0777;
return (old);
}