* src/tgbaalgos/emptiness.hh,

src/tgbaalgos/emptiness.cc (emptiness_check::safe): New method.
* src/tgbaalgos/magic.cc, src/tgbaalgos/magic.hh,
src/tgbaalgos/se05.hh, src/tgbaalgos/se05.cc: Implement it.
* src/tgbatest/randtgba.cc: Simplify.

ChangeLog

@@ -1,5 +1,11 @@
 2005-02-17  Alexandre Duret-Lutz  <adl@src.lip6.fr>
 
+	* src/tgbaalgos/emptiness.hh,
+	src/tgbaalgos/emptiness.cc (emptiness_check::safe): New method.
+	* src/tgbaalgos/magic.cc, src/tgbaalgos/magic.hh,
+	src/tgbaalgos/se05.hh, src/tgbaalgos/se05.cc: Implement it.
+	* src/tgbatest/randtgba.cc: Simplify.
+
 	* src/tgbaalgos/magic.hh, src/tgbaalgos/magic.cc,
 	src/tgbaalgos/se05.hh, src/tgbaalgos/se05.cc: Provide wrapper
 	functions that read the hash-map size from a "bsh" option.

src/tgbaalgos/emptiness.cc

@@ -51,7 +51,8 @@ namespace spot
       }
   }
 
-  std::ostream& print_tgba_run(std::ostream& os,
+  std::ostream&
+  print_tgba_run(std::ostream& os,
 		 const tgba* a,
 		 const tgba_run* run)
   {
@@ -105,6 +106,21 @@ namespace spot
     return dynamic_cast<const unsigned_statistics*>(this);
   }
 
+  const char*
+  emptiness_check_result::parse_options(char* options)
+  {
+    option_map old(o_);
+    const char* s = o_.parse_options(options);
+    options_updated(old);
+    return s;
+  }
+
+  void
+  emptiness_check_result::options_updated(const option_map&)
+  {
+  }
+
+
   emptiness_check::~emptiness_check()
   {
   }
@@ -115,6 +131,26 @@ namespace spot
     return dynamic_cast<const unsigned_statistics*>(this);
   }
 
+  const char*
+  emptiness_check::parse_options(char* options)
+  {
+    option_map old(o_);
+    const char* s = o_.parse_options(options);
+    options_updated(old);
+    return s;
+  }
+
+  void
+  emptiness_check::options_updated(const option_map&)
+  {
+  }
+
+  bool
+  emptiness_check::safe() const
+  {
+    return true;
+  }
+
   std::ostream&
   emptiness_check::print_stats(std::ostream& os) const
   {
@@ -131,7 +167,8 @@ namespace spot
     }
   }
 
-  tgba* tgba_run_to_tgba(const tgba* a, const tgba_run* run)
+  tgba*
+  tgba_run_to_tgba(const tgba* a, const tgba_run* run)
   {
     tgba_explicit* res = new tgba_explicit(a->get_dict());
     res->copy_acceptance_conditions_of(a);

src/tgbaalgos/emptiness.hh

@@ -114,29 +114,18 @@ namespace spot
       return o_;
     }
 
-    /// Modify the options parametrizing how the accepting run is computed.
+    /// Modify the algorithm options.
-    const char*
+    const char* parse_options(char* options);
-    parse_options(char* options)
-    {
-      option_map old(o_);
-      const char* s = o_.parse_options(options);
-      options_updated(old);
-      return s;
-    }
 
     /// Return statistics, if available.
     virtual const unsigned_statistics* statistics() const;
 
   protected:
-    /// React when options are modified.
+    /// Notify option updates.
-    virtual void
+    virtual void options_updated(const option_map& old);
-    options_updated(const option_map& old)
-    {
-      (void)old;
-    }
 
     const tgba* a_;		///< The automaton.
-    option_map o_;		///< The options
+    option_map o_;		///< The options.
   };
 
   /// Common interface to emptiness check algorithms.
@@ -163,19 +152,15 @@ namespace spot
       return o_;
     }
 
-    /// Modify the options parametrizing how the accepting run is realized.
+    /// Modify the algorithm options.
-    const char*
+    const char* parse_options(char* options);
-    parse_options(char* options)
+
-    {
+    /// Return false iff accepting_run() can return 0 for non-empty automata.
-      option_map old(o_);
+    virtual bool safe() const;
-      const char* s = o_.parse_options(options);
-      options_updated(old);
-      return s;
-    }
 
     /// \brief Check whether the automaton contain an accepting run.
     ///
-    /// Return 0 if the automaton accept no run.  Return an instance
+    /// Return 0 if the automaton accepts no run.  Return an instance
     /// of emptiness_check_result otherwise.  This instance might
     /// allow to obtain one sample acceptance run.  The result has to
     /// be destroyed before the emptiness_check instance that
@@ -183,6 +168,10 @@ namespace spot
     ///
     /// Some emptiness_check algorithms may allow check() to be called
     /// several time, but generally you should not assume that.
+    ///
+    /// Some emptiness_check algorithms, especially those using bit state
+    /// hashing may return 0 even if the automaton is not empty.
+    /// \see safe()
     virtual emptiness_check_result* check() = 0;
 
     /// Return statistics, if available.
@@ -191,11 +180,8 @@ namespace spot
     /// Print statistics, if any.
     virtual std::ostream& print_stats(std::ostream& os) const;
 
-    /// React when options are modified.
+    /// Notify option updates.
-    virtual void options_updated(const option_map& old)
+    virtual void options_updated(const option_map& old);
-    {
-      (void)old;
-    }
 
   protected:
     const tgba* a_;		///< The automaton.

src/tgbaalgos/magic.cc

@@ -125,6 +125,11 @@ namespace spot
         return os;
       }
 
+      virtual bool safe() const
+      {
+	return heap::Safe;
+      }
+
       const heap& get_heap() const
       {
 	return h;
@@ -421,6 +426,8 @@ namespace spot
     class explicit_magic_search_heap
     {
     public:
+      enum { Safe = 1 };
+
       class color_ref
       {
       public:
@@ -505,6 +512,8 @@ namespace spot
     class bsh_magic_search_heap
     {
     public:
+      enum { Safe = 0 };
+
       class color_ref
       {
       public:

src/tgbaalgos/se05.cc

@@ -125,6 +125,11 @@ namespace spot
         return os;
       }
 
+      virtual bool safe() const
+      {
+	return heap::Safe;
+      }
+
       const heap& get_heap() const
       {
 	return h;
@@ -436,6 +441,8 @@ namespace spot
       typedef Sgi::hash_map<const state*, color,
                 state_ptr_hash, state_ptr_equal> hash_type;
     public:
+      enum { Safe = 1 };
+
       class color_ref
       {
       public:
@@ -568,6 +575,8 @@ namespace spot
       typedef Sgi::hash_set<const state*,
                 state_ptr_hash, state_ptr_equal> hcyan_type;
     public:
+      enum { Safe = 0 };
+
       class color_ref
       {
       public:

src/tgbatest/randtgba.cc

@@ -75,37 +75,36 @@ struct ec_algo
   spot::emptiness_check* (*construct)(const spot::tgba*, spot::option_map o);
   unsigned int min_acc;
   unsigned int max_acc;
-  bool safe;
 };
 
 ec_algo ec_algos[] =
   {
     { "Cou99",          "!poprem",
-                        couvreur99_cons,                     0, -1U, true },
+                        couvreur99_cons,                     0, -1U },
     { "Cou99_shy-",     "!poprem shy !group",
-                        couvreur99_cons,                     0, -1U, true },
+                        couvreur99_cons,                     0, -1U },
     { "Cou99_shy",      "!poprem shy group",
-                        couvreur99_cons,                     0, -1U, true },
+                        couvreur99_cons,                     0, -1U },
     { "Cou99_rem",      "poprem",
-                        couvreur99_cons,                     0, -1U, true },
+                        couvreur99_cons,                     0, -1U },
     { "Cou99_rem_shy-", "poprem shy !group",
-                        couvreur99_cons,                     0, -1U, true },
+                        couvreur99_cons,                     0, -1U },
     { "Cou99_rem_shy",  "poprem shy group",
-                        couvreur99_cons,                     0, -1U, true },
+                        couvreur99_cons,                     0, -1U },
     { "CVWY90",         0,
-                        spot::magic_search,                  0,   1, true },
+                        spot::magic_search,                  0,   1 },
     { "CVWY90_bsh",     "bsh=4K",
-                        spot::magic_search,                  0,   1, false },
+                        spot::magic_search,                  0,   1 },
     { "GV04",           0,
-                        spot::explicit_gv04_check,           0,   1, true },
+                        spot::explicit_gv04_check,           0,   1 },
     { "SE05",           0,
-                        spot::se05,                          0,   1, true },
+                        spot::se05,                          0,   1 },
     { "SE05_bsh",       "bsh=4K",
-                        spot::se05,                          0,   1, false },
+                        spot::se05,                          0,   1 },
     { "Tau03",          0,
-                        spot::explicit_tau03_search,         1, -1U, true },
+                        spot::explicit_tau03_search,         1, -1U },
     { "Tau03_opt",      0,
-                        spot::explicit_tau03_opt_search,     0, -1U, true },
+                        spot::explicit_tau03_opt_search,     0, -1U },
   };
 
 spot::option_map options;
@@ -1038,7 +1037,7 @@ main(int argc, char** argv)
 		    }
 		  else
 		    {
-		      if (ec_algos[i].safe)
+		      if (ec->safe())
 			{
 			  if (!opt_paper)
 			    std::cout << "empty language" << std::endl;