Commit ec268534 authored by Sebastian Thiel's avatar Sebastian Thiel
Browse files

Fix for empty stacks 

The culprit is that `sk_num(stack)` can return -1
as c_int if there is no stack allocated.

Previously, thanks to unsafe casts, this would result in
a isize::max() for len() and iteration size if there was no stack.

Now this case is handled specifically, which fixes the issue.
parent f92ac247

openssl/src/stack.rs

+11 −2
Original line number Diff line number Diff line
@@ -116,7 +116,7 @@ pub struct IntoIter<T: Stackable> { 


impl<T: Stackable> IntoIter<T> {

    fn stack_len(&self) -> c_int {

        unsafe { OPENSSL_sk_num(self.stack as *mut _) }

        safe_stack_size(self.stack as *mut _) as c_int

    }

}
@@ -154,6 +154,15 @@ impl<T: Stackable> ExactSizeIterator for IntoIter<T> {} 


pub struct StackRef<T: Stackable>(Opaque, PhantomData<T>);



fn safe_stack_size(stack: *mut OPENSSL_STACK) -> usize {

    let l = unsafe { OPENSSL_sk_num(stack) as isize };

    if l < 0 {

        0

    } else {

        l as usize

    }

}



impl<T: Stackable> ForeignTypeRef for StackRef<T> {

    type CType = T::StackType;

}
@@ -165,7 +174,7 @@ impl<T: Stackable> StackRef<T> { 


    /// Returns the number of items in the stack

    pub fn len(&self) -> usize {

        unsafe { OPENSSL_sk_num(self.as_stack()) as usize }

        safe_stack_size(self.as_stack())

    }



    pub fn iter(&self) -> Iter<T> {