From 597d05b8f8ceb754cbfe5c3b6789be6786fb0149 Mon Sep 17 00:00:00 2001
From: Steven Fackler <sfackler@palantir.com>
Date: Sun, 6 Nov 2016 23:46:42 -0800
Subject: [PATCH] Add stack creation and push

---
 openssl-sys/src/ossl10x.rs |  2 ++
 openssl-sys/src/ossl110.rs |  2 ++
 openssl/src/lib.rs         |  4 ++++
 openssl/src/ssl/mod.rs     |  4 ++++
 openssl/src/stack.rs       | 29 ++++++++++++++++++++++++-----
 openssl/src/types.rs       |  3 +++
 6 files changed, 39 insertions(+), 5 deletions(-)

diff --git a/openssl-sys/src/ossl10x.rs b/openssl-sys/src/ossl10x.rs
index acaf85ec..f552be01 100644
--- a/openssl-sys/src/ossl10x.rs
+++ b/openssl-sys/src/ossl10x.rs
@@ -602,10 +602,12 @@ extern {
     pub fn EVP_MD_CTX_create() -> *mut EVP_MD_CTX;
     pub fn EVP_MD_CTX_destroy(ctx: *mut EVP_MD_CTX);
 
+    pub fn sk_new_null() -> *mut _STACK;
     pub fn sk_num(st: *const _STACK) -> c_int;
     pub fn sk_value(st: *const _STACK, n: c_int) -> *mut c_void;
     pub fn sk_free(st: *mut _STACK);
     pub fn sk_pop_free(st: *mut _STACK, free: Option<unsafe extern "C" fn (*mut c_void)>);
+    pub fn sk_push(st: *mut _STACK, data: *mut c_void) -> c_int;
     pub fn sk_pop(st: *mut _STACK) -> *mut c_void;
 
     pub fn SSLeay() -> c_ulong;
diff --git a/openssl-sys/src/ossl110.rs b/openssl-sys/src/ossl110.rs
index 1d68b601..eca4c84e 100644
--- a/openssl-sys/src/ossl110.rs
+++ b/openssl-sys/src/ossl110.rs
@@ -151,7 +151,9 @@ extern {
 
     pub fn OpenSSL_version_num() -> c_ulong;
     pub fn OpenSSL_version(key: c_int) -> *const c_char;
+    pub fn OPENSSL_sk_new_null() -> *mut ::OPENSSL_STACK;
     pub fn OPENSSL_sk_free(st: *mut ::OPENSSL_STACK);
     pub fn OPENSSL_sk_pop_free(st: *mut ::OPENSSL_STACK, free: Option<unsafe extern "C" fn (*mut c_void)>);
+    pub fn OPENSSL_sk_push(st: *mut ::OPENSSL_STACK, data: *const c_void) -> c_int;
     pub fn OPENSSL_sk_pop(st: *mut ::OPENSSL_STACK) -> *mut c_void;
 }
diff --git a/openssl/src/lib.rs b/openssl/src/lib.rs
index ec8d93eb..5750b410 100644
--- a/openssl/src/lib.rs
+++ b/openssl/src/lib.rs
@@ -31,6 +31,10 @@ macro_rules! type_ {
             unsafe fn from_ptr(ptr: *mut $c) -> $n {
                 $n(ptr)
             }
+
+            fn as_ptr(&self) -> *mut $c {
+                self.0
+            }
         }
 
         impl Drop for $n {
diff --git a/openssl/src/ssl/mod.rs b/openssl/src/ssl/mod.rs
index 1e7efc63..7060433f 100644
--- a/openssl/src/ssl/mod.rs
+++ b/openssl/src/ssl/mod.rs
@@ -822,6 +822,10 @@ impl OpenSslType for SslCipher {
     unsafe fn from_ptr(ptr: *mut ffi::SSL_CIPHER) -> SslCipher {
         SslCipher(ptr)
     }
+
+    fn as_ptr(&self) -> *mut ffi::SSL_CIPHER {
+        self.0
+    }
 }
 
 impl Deref for SslCipher {
diff --git a/openssl/src/stack.rs b/openssl/src/stack.rs
index dae42ca8..87aa86c5 100644
--- a/openssl/src/stack.rs
+++ b/openssl/src/stack.rs
@@ -6,14 +6,18 @@ use std::marker::PhantomData;
 use libc::c_int;
 use std::mem;
 
+use {cvt, cvt_p};
+use error::ErrorStack;
 use types::{OpenSslType, OpenSslTypeRef};
 use util::Opaque;
 
 #[cfg(ossl10x)]
 use ffi::{sk_pop as OPENSSL_sk_pop, sk_free as OPENSSL_sk_free, sk_num as OPENSSL_sk_num,
-          sk_value as OPENSSL_sk_value, _STACK as OPENSSL_STACK};
+          sk_value as OPENSSL_sk_value, _STACK as OPENSSL_STACK,
+          sk_new_null as OPENSSL_sk_new_null, sk_push as OPENSSL_sk_push};
 #[cfg(ossl110)]
-use ffi::{OPENSSL_sk_pop, OPENSSL_sk_free, OPENSSL_sk_num, OPENSSL_sk_value, OPENSSL_STACK};
+use ffi::{OPENSSL_sk_pop, OPENSSL_sk_free, OPENSSL_sk_num, OPENSSL_sk_value, OPENSSL_STACK,
+          OPENSSL_sk_new_null, OPENSSL_sk_push};
 
 /// Trait implemented by types which can be placed in a stack.
 ///
@@ -31,9 +35,11 @@ pub trait Stackable: OpenSslType {
 pub struct Stack<T: Stackable>(*mut T::StackType);
 
 impl<T: Stackable> Stack<T> {
-    /// Return a new Stack<T>, taking ownership of the handle
-    pub unsafe fn from_ptr(stack: *mut T::StackType) -> Stack<T> {
-        Stack(stack)
+    pub fn new() -> Result<Stack<T>, ErrorStack> {
+        unsafe {
+            let ptr = try!(cvt_p(OPENSSL_sk_new_null()));
+            Ok(Stack(ptr as *mut _))
+        }
     }
 }
 
@@ -79,6 +85,10 @@ impl<T: Stackable> OpenSslType for Stack<T> {
     unsafe fn from_ptr(ptr: *mut T::StackType) -> Stack<T> {
         Stack(ptr)
     }
+
+    fn as_ptr(&self) -> *mut T::StackType {
+        self.0
+    }
 }
 
 impl<T: Stackable> Deref for Stack<T> {
@@ -198,6 +208,15 @@ impl<T: Stackable> StackRef<T> {
         }
     }
 
+    /// Pushes a value onto the top of the stack.
+    pub fn push(&mut self, data: T) -> Result<(), ErrorStack> {
+        unsafe {
+            try!(cvt(OPENSSL_sk_push(self.as_stack(), data.as_ptr() as *mut _)));
+            mem::forget(data);
+            Ok(())
+        }
+    }
+
     /// Removes the last element from the stack and returns it.
     pub fn pop(&mut self) -> Option<T> {
         unsafe {
diff --git a/openssl/src/types.rs b/openssl/src/types.rs
index 2fadfd42..a444529d 100644
--- a/openssl/src/types.rs
+++ b/openssl/src/types.rs
@@ -13,6 +13,9 @@ pub trait OpenSslType: Sized {
 
     /// Constructs an instance of this type from its raw type.
     unsafe fn from_ptr(ptr: *mut Self::CType) -> Self;
+
+    /// Returns a raw pointer to the wrapped value.
+    fn as_ptr(&self) -> *mut Self::CType;
 }
 
 /// A trait implemented by types which reference borrowed OpenSSL types.