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#include "inc.h"
static int search_dir(
struct inode *ldir_ptr, /* dir record parent */
char string[NAME_MAX], /* component to search for */
ino_t *numb /* pointer to new dir record */
) {
/*
* The search_dir function performs the operation of searching for the
* component ``string" in ldir_ptr. It returns the response and the
* number of the inode in numb.
*/
int r, i;
/*
* This function search a particular element (in string) in a inode and
* return its number.
*/
if ((ldir_ptr->i_stat.st_mode & S_IFMT) != S_IFDIR)
return ENOTDIR;
r = read_directory(ldir_ptr);
if (r != OK)
return r;
if (strcmp(".", string) == 0) {
*numb = ldir_ptr->i_stat.st_ino;
return OK;
}
/* Walk the directory listing. */
for (i = 0; i < ldir_ptr->dir_size; i++) {
if (strcmp(string, ldir_ptr->dir_contents[i].name) == 0) {
*numb = ldir_ptr->dir_contents[i].i_node->i_stat.st_ino;
return OK;
}
}
return ENOENT;
}
int fs_lookup(ino_t dir_nr, char *name, struct fsdriver_node *node,
int *is_mountpt)
{
/* Given a directory and a component of a path, look up the component
* in the directory, find the inode, open it, and return its details.
*/
struct inode *dirp, *rip;
ino_t ino_nr;
int r;
/* Find the starting inode. */
if ((dirp = get_inode(dir_nr)) == NULL)
return EINVAL;
/* Look up the directory entry. */
if ((r = search_dir(dirp, name, &ino_nr)) != OK)
return r;
/* The component has been found in the directory. Get the inode. */
if ((rip = open_inode(ino_nr)) == NULL)
return EIO; /* FIXME: this could have multiple causes */
/* Return its details to the caller. */
node->fn_ino_nr = rip->i_stat.st_ino;
node->fn_mode = rip->i_stat.st_mode;
node->fn_size = rip->i_stat.st_size;
node->fn_uid = rip->i_stat.st_uid;
node->fn_gid = rip->i_stat.st_gid;
node->fn_dev = rip->i_stat.st_rdev;
*is_mountpt = rip->i_mountpoint;
return OK;
}
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