/*
 * Minimal fake declarations of "kernel" data types
 */
struct superblock;

struct inode {
	int i_nlink;
	int i_size;
	int i_ctime;
	int i_mtime;
	struct superblock *i_sb;
};

struct dentry {
	struct inode *d_inode;
};

#define d_inode(dentry) ((dentry)->d_inode)

extern int current_time(struct inode *);
extern void inc_nlink(struct inode *);
extern void ihold(struct inode *);
extern void dget(struct dentry *);
extern void d_instantiate(struct dentry *, struct inode *);
extern int shmem_reserve_inode(struct superblock *);

#define BOGO_DIRENT_SIZE 20

/*
 * The actual function where I'd have expected a warning
 * about "ret might be used uninitialized"
 */
int shmem_link(struct dentry *old_dentry, struct inode *dir,
		      struct dentry *dentry)
{
	struct inode *inode = d_inode(old_dentry);
	int ret;

	/*
	 * No ordinary (disk based) filesystem counts links as inodes;
	 * but each new link needs a new dentry, pinning lowmem, and
	 * tmpfs dentries cannot be pruned until they are unlinked.
	 * But if an O_TMPFILE file is linked into the tmpfs, the
	 * first link must skip that, to get the accounting right.
	 */
	if (inode->i_nlink) {
		ret = shmem_reserve_inode(inode->i_sb);
#ifndef HIDE_PROBLEM
		if (ret)
			return ret;
#endif
	}

	dir->i_size += BOGO_DIRENT_SIZE;
	inode->i_ctime = dir->i_ctime = dir->i_mtime = current_time(inode);
	inc_nlink(inode);
	ihold(inode);		/* New dentry reference */
	dget(dentry);		/* Extra pinning count for the created dentry */
	d_instantiate(dentry, inode);
	return ret;
}