+
+/*
+ * Advisory record locking support
+ */
+ufs_advlock(vp, id, op, fl, flags)
+ struct vnode *vp;
+ caddr_t id;
+ int op;
+ register struct flock *fl;
+ int flags;
+{
+ register struct inode *ip = VTOI(vp);
+ register struct lockf *lock;
+ off_t start, end;
+ int error;
+
+ /*
+ * Avoid the common case of unlocking when inode has no locks.
+ */
+ if (ip->i_lockf == (struct lockf *)0) {
+ if (op != F_SETLK) {
+ fl->l_type = F_UNLCK;
+ return (0);
+ }
+ }
+ /*
+ * Convert the flock structure into a start and end.
+ */
+ switch (fl->l_whence) {
+
+ case SEEK_SET:
+ case SEEK_CUR:
+ /*
+ * Caller is responsible for adding any necessary offset
+ * when SEEK_CUR is used.
+ */
+ start = fl->l_start;
+ break;
+
+ case SEEK_END:
+ start = ip->i_size + fl->l_start;
+ break;
+
+ default:
+ return (EINVAL);
+ }
+ if (start < 0)
+ return (EINVAL);
+ if (fl->l_len == 0)
+ end = -1;
+ else
+ end = start + fl->l_len - 1;
+ /*
+ * Create the lockf structure
+ */
+ MALLOC(lock, struct lockf *, sizeof *lock, M_LOCKF, M_WAITOK);
+ lock->lf_start = start;
+ lock->lf_end = end;
+ lock->lf_id = id;
+ lock->lf_inode = ip;
+ lock->lf_type = fl->l_type;
+ lock->lf_next = (struct lockf *)0;
+ lock->lf_block = (struct lockf *)0;
+ lock->lf_flags = flags;
+ /*
+ * Do the requested operation.
+ */
+ switch(op) {
+ case F_SETLK:
+ return (lf_setlock(lock));
+
+ case F_UNLCK:
+ error = lf_clearlock(lock);
+ FREE(lock, M_LOCKF);
+ return (error);
+
+ case F_GETLK:
+ error = lf_getlock(lock, fl);
+ FREE(lock, M_LOCKF);
+ return (error);
+
+ default:
+ free(lock, M_LOCKF);
+ return (EINVAL);
+ }
+ /* NOTREACHED */
+}
projects / unix-history / blobdiff