Problem: read-only arguments of mtrie are not declared as const

Solution: add const, introduce typedef

src/mtrie.cpp

@@ -57,14 +57,12 @@ zmq::mtrie_t::~mtrie_t ()
     }
 }
 
-bool zmq::mtrie_t::add (unsigned char *prefix_, size_t size_, pipe_t *pipe_)
+bool zmq::mtrie_t::add (prefix_t prefix_, size_t size_, pipe_t *pipe_)
 {
     return add_helper (prefix_, size_, pipe_);
 }
 
-bool zmq::mtrie_t::add_helper (unsigned char *prefix_,
-                               size_t size_,
-                               pipe_t *pipe_)
+bool zmq::mtrie_t::add_helper (prefix_t prefix_, size_t size_, pipe_t *pipe_)
 {
     //  We are at the node corresponding to the prefix. We are done.
     if (!size_) {
@@ -139,9 +137,7 @@ bool zmq::mtrie_t::add_helper (unsigned char *prefix_,
 
 
 void zmq::mtrie_t::rm (pipe_t *pipe_,
-                       void (*func_) (unsigned char *data_,
-                                      size_t size_,
-                                      void *arg_),
+                       void (*func_) (prefix_t data_, size_t size_, void *arg_),
                        void *arg_,
                        bool call_on_uniq_)
 {
@@ -154,7 +150,7 @@ void zmq::mtrie_t::rm_helper (pipe_t *pipe_,
                               unsigned char **buff_,
                               size_t buffsize_,
                               size_t maxbuffsize_,
-                              void (*func_) (unsigned char *data_,
+                              void (*func_) (prefix_t data_,
                                              size_t size_,
                                              void *arg_),
                               void *arg_,
@@ -275,14 +271,12 @@ void zmq::mtrie_t::rm_helper (pipe_t *pipe_,
     }
 }
 
-bool zmq::mtrie_t::rm (unsigned char *prefix_, size_t size_, pipe_t *pipe_)
+bool zmq::mtrie_t::rm (prefix_t prefix_, size_t size_, pipe_t *pipe_)
 {
     return rm_helper (prefix_, size_, pipe_);
 }
 
-bool zmq::mtrie_t::rm_helper (unsigned char *prefix_,
-                              size_t size_,
-                              pipe_t *pipe_)
+bool zmq::mtrie_t::rm_helper (prefix_t prefix_, size_t size_, pipe_t *pipe_)
 {
     if (!size_) {
         if (pipes) {
@@ -372,7 +366,7 @@ bool zmq::mtrie_t::rm_helper (unsigned char *prefix_,
     return ret;
 }
 
-void zmq::mtrie_t::match (unsigned char *data_,
+void zmq::mtrie_t::match (prefix_t data_,
                           size_t size_,
                           void (*func_) (pipe_t *pipe_, void *arg_),
                           void *arg_)

src/mtrie.hpp

@@ -44,43 +44,45 @@ class pipe_t;
 class mtrie_t
 {
   public:
+    typedef const unsigned char *prefix_t;
+
     mtrie_t ();
     ~mtrie_t ();
 
     //  Add key to the trie. Returns true if it's a new subscription
     //  rather than a duplicate.
-    bool add (unsigned char *prefix_, size_t size_, zmq::pipe_t *pipe_);
+    bool add (prefix_t prefix_, size_t size_, zmq::pipe_t *pipe_);
 
     //  Remove all subscriptions for a specific peer from the trie.
     //  The call_on_uniq_ flag controls if the callback is invoked
     //  when there are no subscriptions left on some topics or on
     //  every removal.
-    void rm (zmq::pipe_t *pipe_,
-             void (*func_) (unsigned char *data_, size_t size_, void *arg_),
-             void *arg_,
-             bool call_on_uniq_);
+    void
+    rm (zmq::pipe_t *pipe_,
+        void (*func_) (const unsigned char *data_, size_t size_, void *arg_),
+        void *arg_,
+        bool call_on_uniq_);
 
     //  Remove specific subscription from the trie. Return true is it was
     //  actually removed rather than de-duplicated.
-    bool rm (unsigned char *prefix_, size_t size_, zmq::pipe_t *pipe_);
+    bool rm (prefix_t prefix_, size_t size_, zmq::pipe_t *pipe_);
 
     //  Signal all the matching pipes.
-    void match (unsigned char *data_,
+    void match (prefix_t data_,
                 size_t size_,
                 void (*func_) (zmq::pipe_t *pipe_, void *arg_),
                 void *arg_);
 
   private:
-    bool add_helper (unsigned char *prefix_, size_t size_, zmq::pipe_t *pipe_);
-    void
-    rm_helper (zmq::pipe_t *pipe_,
-               unsigned char **buff_,
-               size_t buffsize_,
-               size_t maxbuffsize_,
-               void (*func_) (unsigned char *data_, size_t size_, void *arg_),
-               void *arg_,
-               bool call_on_uniq_);
-    bool rm_helper (unsigned char *prefix_, size_t size_, zmq::pipe_t *pipe_);
+    bool add_helper (prefix_t prefix_, size_t size_, zmq::pipe_t *pipe_);
+    void rm_helper (zmq::pipe_t *pipe_,
+                    unsigned char **buff_,
+                    size_t buffsize_,
+                    size_t maxbuffsize_,
+                    void (*func_) (prefix_t data_, size_t size_, void *arg_),
+                    void *arg_,
+                    bool call_on_uniq_);
+    bool rm_helper (prefix_t prefix_, size_t size_, zmq::pipe_t *pipe_);
     bool is_redundant () const;
 
     typedef std::set<zmq::pipe_t *> pipes_t;

src/xpub.cpp

@@ -188,7 +188,7 @@ int zmq::xpub_t::xsetsockopt (int option_,
     return 0;
 }
 
-static void stub (unsigned char *data_, size_t size_, void *arg_)
+static void stub (zmq::mtrie_t::prefix_t data_, size_t size_, void *arg_)
 {
     LIBZMQ_UNUSED (data_);
     LIBZMQ_UNUSED (size_);
@@ -295,7 +295,7 @@ bool zmq::xpub_t::xhas_in ()
     return !pending_data.empty ();
 }
 
-void zmq::xpub_t::send_unsubscription (unsigned char *data_,
+void zmq::xpub_t::send_unsubscription (zmq::mtrie_t::prefix_t data_,
                                        size_t size_,
                                        void *arg_)
 {

src/xpub.hpp

@@ -66,8 +66,9 @@ class xpub_t : public socket_base_t
   private:
     //  Function to be applied to the trie to send all the subscriptions
     //  upstream.
-    static void
-    send_unsubscription (unsigned char *data_, size_t size_, void *arg_);
+    static void send_unsubscription (zmq::mtrie_t::prefix_t data_,
+                                     size_t size_,
+                                     void *arg_);
 
     //  Function to be applied to each matching pipes.
     static void mark_as_matching (zmq::pipe_t *pipe_, void *arg_);