making tree function in xv6 - unix

Question

I want to make tree command in xv6, if you don't know the tree is to list out directories on the terminal. I know this is probably easy for you but the code is so far
#include "types.h"
#include "stat.h"
#include "user.h"
#include "fcntl.h"
#include "fs.h"
#include "file.h"
int
main(int argc, char *argv[])
{
if(argc < 2){
printf(2, "Usage: tree [path]...\n");
exit();
}
tree(argv[1]);
int fd = open(argv[1],O_RDONLY);
if(fd<0)
return -1;
struct dirent dir;
while(read(fd,&dir,sizeof(dir))!=0){
printf(1,"|_ %d,%d",dir.name,dir.inum);
//struct stat *st;
struct inode ip;
ip= getinode(dir.inum);
if(ip.type==T_DIR){
int i;
for(i=0;i<NDIRECT;i++ ){
uint add=ip.addrs[i];
printf(1,"%d",add);
}
}
}
return 0;
}
and it has been giving me numerous error on the terminal the first being file.h:17:20: error: field ‘lock’ has incomplete type
struct sleeplock lock; // protects everything below here
^~~~
I'm searching for sleeplock and there is nothing like that in the code. What is wrong with the code? Thank you for your help

Answer 1

You cannot use kernel headers (like file.h) in a user code. To use kernel functionnalities in your code, you must use system calls.
To achieve what you want, you could start from ls function and make it recursive.
One example made quickly:
I added a parameter to the ls function to display the depth of crawling
and call itself on each directory elements but two first which are . and ..
void
ls(char *path, int decal)
{
char buf[512], *p;
int fd, i, skip = 2;
struct dirent de;
struct stat st;
if((fd = open(path, 0)) < 0){
printf(2, "tree: cannot open %s\n", path);
return;
}
if(fstat(fd, &st) < 0){
printf(2, "tree: cannot stat %s\n", path);
close(fd);
return;
}
switch(st.type){
case T_FILE:
for (i = 0; i < decal; i++)
printf(1, " ");
printf(1, "%s %d %d %d\n", fmtname(path), st.type, st.ino, st.size);
break;
case T_DIR:
if(strlen(path) + 1 + DIRSIZ + 1 > sizeof buf){
printf(1, "tree: path too long\n");
break;
}
strcpy(buf, path);
p = buf+strlen(buf);
*p++ = '/';
while(read(fd, &de, sizeof(de)) == sizeof(de)){
if(de.inum == 0)
continue;
memmove(p, de.name, DIRSIZ);
p[DIRSIZ] = 0;
if(stat(buf, &st) < 0){
printf(1, "tree: cannot stat %s\n", buf);
continue;
}
for (i = 0; i < decal; i++)
printf(1, " ");
printf(1, "%s %d %d %d\n", fmtname(buf), st.type, st.ino, st.size);
if (skip)
skip--;
else
ls(buf, decal+1);
}
break;
}
close(fd);
}