Make RefCount<> more sensible

the previous version of operator*() made no sense. E.g., it violated the invariant
(*ptr).foo <=> ptr->foo. The dereferencing operator now returns a reference to the pointed-to
object, rather than a pointer to it.

I also added a bool conversion operator, which can be used in testing the NULL-ness of the
pointer. Anyone wondering if that could be done in a simpler way is encouraged to read
<http://www.artima.com/cppsource/safebool.html>.

And, finally, I removed the mutable flag from the m_data member, since it does not need it.

6 files changed, 16 insertions, 12 deletions

diff --git a/src/FbTk/LogicCommands.cc b/src/FbTk/LogicCommands.cc
index b3abe31..bda67f5 100644
--- a/src/FbTk/LogicCommands.cc
+++ b/src/FbTk/LogicCommands.cc
@@ -44,7 +44,7 @@ M *addCommands(M *macro, const string &args, bool trusted) {
     std::vector<std::string>::iterator it = cmds.begin(), it_end = cmds.end();
     for (; it != it_end; ++it) {
         cmd = CommandParser<bool>::instance().parse(*it, trusted);
-        if (*cmd)
+        if (cmd)
             macro->add(cmd);
     }
 
@@ -91,13 +91,13 @@ Command<void> *IfCommand::parse(const std::string &command, const std::string &a
         return 0;
 
     cond = CommandParser<bool>::instance().parse(cmds[0], trusted);
-    if (*cond == 0)
+    if (cond == 0)
         return 0;
 
     t = CommandParser<void>::instance().parse(cmds[1], trusted);
     if (cmds.size() >= 3)
         f = CommandParser<void>::instance().parse(cmds[2], trusted);
-    if (*t == 0 && *f == 0)
+    if (t == 0 && f == 0)
         return 0;
 
     return new IfCommand(cond, t, f);
diff --git a/src/FbTk/LogicCommands.hh b/src/FbTk/LogicCommands.hh
index 5e84473..c0cb938 100644
--- a/src/FbTk/LogicCommands.hh
+++ b/src/FbTk/LogicCommands.hh
@@ -38,9 +38,9 @@ public:
         m_cond(cond), m_t(t), m_f(f) { }
     void execute() {
         if (m_cond->execute()) {
-            if (*m_t) m_t->execute();
+            if (m_t) m_t->execute();
         } else
-            if (*m_f) m_f->execute();
+            if (m_f) m_f->execute();
     }
     static Command<void> *parse(const std::string &cmd, const std::string &args,
                           bool trusted);
diff --git a/src/FbTk/MacroCommand.cc b/src/FbTk/MacroCommand.cc
index 0b7a6b8..e04d92a 100644
--- a/src/FbTk/MacroCommand.cc
+++ b/src/FbTk/MacroCommand.cc
@@ -42,7 +42,7 @@ M *addCommands(M *macro, const std::string &args, bool trusted) {
         std::list<std::string>::iterator it = cmds.begin(), it_end = cmds.end();
         for (; it != it_end; ++it) {
             cmd = CommandParser<void>::instance().parse(*it, trusted);
-            if (*cmd)
+            if (cmd)
                 macro->add(cmd);
         }
     }
diff --git a/src/FbTk/MultiButtonMenuItem.cc b/src/FbTk/MultiButtonMenuItem.cc
index ed67c83..1b61a99 100644
--- a/src/FbTk/MultiButtonMenuItem.cc
+++ b/src/FbTk/MultiButtonMenuItem.cc
@@ -55,7 +55,7 @@ void MultiButtonMenuItem::click(int button, int time, unsigned int mods) {
     if (button <= 0 || button > static_cast<signed>(buttons()) || buttons() == 0)
         return;
 
-    if (*m_button_exe[button - 1] != 0)
+    if (m_button_exe[button - 1] != 0)
         m_button_exe[button - 1]->execute();
 }
 
diff --git a/src/FbTk/RefCount.hh b/src/FbTk/RefCount.hh
index 6d1b9b7..597f847 100644
--- a/src/FbTk/RefCount.hh
+++ b/src/FbTk/RefCount.hh
@@ -27,6 +27,8 @@ namespace FbTk {
 /// holds a pointer with reference counting, similar to std:auto_ptr
 template <typename Pointer>
 class RefCount {
+    typedef Pointer* RefCount::*bool_type;
+
 public:
     RefCount();
     explicit RefCount(Pointer *p);
@@ -35,9 +37,11 @@ public:
     ~RefCount();
     RefCount<Pointer> &operator = (const RefCount<Pointer> &copy);
     RefCount<Pointer> &operator = (Pointer *p);
-    Pointer *operator * () const { return get(); } 
+    Pointer &operator * () const { return *get(); }
     Pointer *operator -> () const { return get(); }
     Pointer *get() const { return m_data; }
+    /// conversion to "bool"
+    operator bool_type() const { return m_data ? &RefCount::m_data : 0; }
 
 private:
     /// increase reference count
@@ -45,7 +49,7 @@ private:
     /// decrease reference count
     void decRefCount();
     Pointer *m_data; ///< data holder
-    mutable unsigned int *m_refcount; ///< holds reference counting
+    unsigned int *m_refcount; ///< holds reference counting
 };
 
 // implementation
diff --git a/src/FbTk/Timer.cc b/src/FbTk/Timer.cc
index 60df968..cb9ac59 100644
--- a/src/FbTk/Timer.cc
+++ b/src/FbTk/Timer.cc
@@ -98,7 +98,7 @@ void Timer::start() {
     gettimeofday(&m_start, 0);
 
     // only add Timers that actually DO something
-    if ((! m_timing || m_interval != 0) && *m_handler) {
+    if ((! m_timing || m_interval != 0) && m_handler) {
         m_timing = true;
         addTimer(this); //add us to the list
     }
@@ -121,7 +121,7 @@ void Timer::makeEndTime(timeval &tm) const {
 
 
 void Timer::fireTimeout() {
-    if (*m_handler)
+    if (m_handler)
         m_handler->execute();
 }
 
@@ -273,7 +273,7 @@ Command<void> *DelayedCmd::parse(const std::string &command,
         return 0;
 
     RefCount<Command<void> > cmd(CommandParser<void>::instance().parse(cmd_str, trusted));
-    if (*cmd == 0)
+    if (cmd == 0)
         return 0;
 
     int delay = 200000;