From 8d1178788a203e032b8ab10ce4ec7059bc18d203 Mon Sep 17 00:00:00 2001
From: Danila Fedorin <danila.fedorin@gmail.com>
Date: Thu, 20 Jul 2017 21:58:51 -0700
Subject: [PATCH] Update libds.

---
 external/libds    |  2 +-
 include/pairmap.h |  6 +++---
 src/pairmap.c     | 14 +++++++-------
 3 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/external/libds b/external/libds
index cd822fe..1d037dd 160000
--- a/external/libds
+++ b/external/libds
@@ -1 +1 @@
-Subproject commit cd822fedfc1357919b6cba46a9b61e58e2fc1dde
+Subproject commit 1d037dd31e4a242518e2f562d8d2c980443a1869
diff --git a/include/pairmap.h b/include/pairmap.h
index 50f5d8c..019e8ec 100644
--- a/include/pairmap.h
+++ b/include/pairmap.h
@@ -36,20 +36,20 @@ typedef struct pairmap_key_s pairmap_key;
  * @param key the key for the hash table.
  * @return the resulting hash.
  */
-unsigned long pairmap_hash_func(void* key);
+unsigned long pairmap_hash_func(const void* key);
 /**
  * Compares two pairmap_key's.
  * @param a the first pairmap_key
  * @param b the second pairmap_key
  * @return
  */
-int pairmap_cmp_func(void* a, void* b);
+int pairmap_cmp_func(const void* a, const void* b);
 /**
  * Copies a pairmap_key.
  * @param key the key to copy.
  * @return the copy of the key.
  */
-void* pairmap_copy_func(void* key);
+void* pairmap_copy_func(const void* key);
 /**
  * Initializes a hash table with functions used for pair maps.
  * @param ht the hash table to initialize.
diff --git a/src/pairmap.c b/src/pairmap.c
index 2745573..32d429e 100644
--- a/src/pairmap.c
+++ b/src/pairmap.c
@@ -1,19 +1,19 @@
 #include "pairmap.h"
 #include <stdlib.h>
 
-unsigned long pairmap_hash_func(void* key){
-  pairmap_key* new_key = key;
+unsigned long pairmap_hash_func(const void* key){
+  const pairmap_key* new_key = key;
   unsigned int hash = 0;
   hash |= ((new_key->x & 0xffff) << 8) + (new_key->y & 0xffff);
   return hash;
 }
-int pairmap_cmp_func(void* a, void* b){
-  pairmap_key* new_key_a = a;
-  pairmap_key* new_key_b = b;
+int pairmap_cmp_func(const void* a, const void* b){
+  const pairmap_key* new_key_a = a;
+  const pairmap_key* new_key_b = b;
   return (new_key_a->x == new_key_b->x) && (new_key_a->y == new_key_b->y);
 }
-void* pairmap_copy_func(void* key){
-  pairmap_key* copy_from = key;
+void* pairmap_copy_func(const void* key){
+  const pairmap_key* copy_from = key;
   pairmap_key* new_key = malloc(sizeof(*new_key));
   if(new_key){
     new_key->x = copy_from->x;