randomize: new function

* src/tgbaalgos/randomize.cc, src/tgbaalgos/randomize.hh: New files.
* src/tgbaalgos/Makefile.am: Add them.
* src/graph/graph.hh (rename_states_): New method.
* src/bin/autfilt.cc: Add options --randomize and --seed.
* src/tgbatest/randomize.test: Test them.
* src/tgbatest/Makefile.am: Add randomize.test.
* NEWS: Mention randomize().

NEWS

@@ -43,6 +43,10 @@ New in spot 1.99a (not yet released)
       used in a stream.  The parser currently ignore all optional
       headers (starting with a lowercase letter).
 
+    - randomize() is a new algorithm that reorder the states
+      and transition of an automaton at random.  It can be
+      used from the command-line using "autfilt --randomize".
+
     - Spot is now compiling in C++11 mode.  The set of features we use
       requires GCC >= 4.6 or Clang >= 3.1.  These minimum versions
       are old enough that it should not be an issue to most people.

src/bin/autfilt.cc

@@ -39,11 +39,13 @@
 #include "tgba/bddprint.hh"
 #include "misc/optionmap.hh"
 #include "misc/timer.hh"
+#include "misc/random.hh"
 #include "hoaparse/public.hh"
 #include "tgbaalgos/sccinfo.hh"
+#include "tgbaalgos/randomize.hh"
 
 
-const char argp_program_doc[] ="\
+static const char argp_program_doc[] ="\
 Convert, transform, and filter Büchi automata.\n\
 ";
 
@@ -53,6 +55,8 @@ Convert, transform, and filter Büchi automata.\n\
 #define OPT_LBTT 3
 #define OPT_SPOT 4
 #define OPT_STATS 5
+#define OPT_RANDOMIZE 6
+#define OPT_SEED 7
 
 static const argp_option options[] =
   {
@@ -111,24 +115,44 @@ static const argp_option options[] =
     { "%%", 0, 0, OPTION_DOC | OPTION_NO_USAGE,
       "a single %", 0 },
     /**************************************************/
+    { 0, 0, 0, 0, "Transformation:", -1 },
+    { "randomize", OPT_RANDOMIZE, "s|t", OPTION_ARG_OPTIONAL,
+      "randomize states and transitions (specify 's' or 't' to"
+      "randomize only states or transitions)", 0 },
+    /**************************************************/
     { 0, 0, 0, 0, "Miscellaneous options:", -1 },
     { "extra-options", 'x', "OPTS", 0,
       "fine-tuning options (see spot-x (7))", 0 },
+    { "seed", OPT_SEED, "INT", 0,
+      "seed for the random number generator (0)", 0 },
     { 0, 0, 0, 0, 0, 0 }
   };
 
-const struct argp_child children[] =
+static const struct argp_child children[] =
   {
     { &post_argp_disabled, 0, 0, 20 },
     { &misc_argp, 0, 0, -1 },
     { 0, 0, 0, 0 }
   };
 
-enum output_format { Dot, Lbtt, Lbtt_t, Spin, Spot, Stats, Hoa } format = Dot;
-bool utf8 = false;
-const char* stats = "";
-const char* hoa_opt = 0;
-spot::option_map extra_options;
+static enum output_format { Dot, Lbtt, Lbtt_t, Spin, Spot, Stats, Hoa }
+  format = Dot;
+static const char* stats = "";
+static const char* hoa_opt = 0;
+static spot::option_map extra_options;
+static bool randomize_st = false;
+static bool randomize_tr = false;
+static int opt_seed = 0;
+
+static int
+to_int(const char* s)
+{
+  char* endptr;
+  int res = strtol(s, &endptr, 10);
+  if (*endptr)
+    error(2, 0, "failed to parse '%s' as an integer.", s);
+  return res;
+}
 
 static int
 parse_opt(int key, char* arg, struct argp_state*)
@@ -180,6 +204,31 @@ parse_opt(int key, char* arg, struct argp_state*)
 	  format = Lbtt;
 	}
       break;
+    case OPT_RANDOMIZE:
+      if (arg)
+	{
+	  for (auto p = arg; *p; ++p)
+	    switch (*p)
+	      {
+	      case 's':
+		randomize_st = true;
+		break;
+	      case 't':
+		randomize_tr = true;
+		break;
+	      default:
+		error(2, 0, "unknown argument for --randomize: '%c'", *p);
+	      }
+	}
+      else
+	{
+	  randomize_tr = true;
+	  randomize_st = true;
+	}
+      break;
+    case OPT_SEED:
+      opt_seed = to_int(arg);
+      break;
     case OPT_SPOT:
       format = Spot;
       break;
@@ -301,6 +350,9 @@ namespace
       auto aut = post.run(haut->aut, nullptr);
       const double conversion_time = sw.stop();
 
+      if (randomize_st || randomize_tr)
+	spot::randomize(aut, randomize_st, randomize_tr);
+
       switch (format)
 	{
 	case Dot:
@@ -385,6 +437,8 @@ main(int argc, char** argv)
   if (jobs.empty())
     jobs.emplace_back("-", true);
 
+  spot::srand(opt_seed);
+
   spot::postprocessor post(&extra_options);
   post.set_pref(pref | comp);
   post.set_type(type);

src/graph/graph.hh

@@ -725,6 +725,21 @@ namespace spot
       //dump_storage(std::cerr);
     }
 
+    // Rename all the states in the transition vector.  The
+    // transitions_ vector is left in a state that is incorrect and
+    // should eventually be fixed by a call to chain_transitions_()
+    // before any iteration on the successor of a state is performed.
+    void rename_states_(const std::vector<unsigned>& newst)
+    {
+      assert(newst.size() == states_.size());
+      unsigned tend = transitions_.size();
+      for (unsigned t = 1; t < tend; t++)
+	{
+	  transitions_[t].dst = newst[transitions_[t].dst];
+	  transitions_[t].src = newst[transitions_[t].src];
+	}
+    }
+
     void defrag_states(std::vector<unsigned>&& newst, unsigned used_states)
     {
       assert(newst.size() == states_.size());

src/tgbaalgos/Makefile.am

@@ -57,6 +57,7 @@ tgbaalgos_HEADERS = \
   product.hh \
   projrun.hh \
   randomgraph.hh \
+  randomize.hh \
   reachiter.hh \
   reducerun.hh \
   replayrun.hh \
@@ -108,6 +109,7 @@ libtgbaalgos_la_SOURCES = \
   product.cc \
   projrun.cc \
   randomgraph.cc \
+  randomize.cc \
   reachiter.cc \
   reducerun.cc \
   replayrun.cc \

src/tgbaalgos/randomize.cc

@@ -0,0 +1,55 @@
+// -*- coding: utf-8 -*-
+// Copyright (C) 2014 Laboratoire de Recherche et Développement de
+// l'Epita (LRDE).
+//
+// This file is part of Spot, a model checking library.
+//
+// Spot is free software; you can redistribute it and/or modify it
+// under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 3 of the License, or
+// (at your option) any later version.
+//
+// Spot is distributed in the hope that it will be useful, but WITHOUT
+// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+// or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
+// License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+#include <algorithm>
+#include <numeric>
+#include "randomize.hh"
+#include "misc/random.hh"
+
+namespace spot
+{
+  SPOT_API void
+  randomize(tgba_digraph_ptr& aut, bool randomize_states,
+	    bool randomize_transitions)
+  {
+    if (!randomize_states && !randomize_transitions)
+      return;
+    auto& g = aut->get_graph();
+    if (randomize_states)
+      {
+	unsigned n = g.num_states();
+	std::vector<unsigned> nums(n);
+	std::iota(nums.begin(), nums.end(), 0);
+	std::random_shuffle(nums.begin(), nums.end(), spot::mrand);
+	g.rename_states_(nums);
+	aut->set_init_state(nums[aut->get_init_state_number()]);
+      }
+    if (randomize_transitions)
+      {
+	auto begin = g.transitions().begin() + 1;
+	auto end = g.transitions().end();
+	std::random_shuffle(begin, end, spot::mrand);
+      }
+
+    typedef tgba_digraph::graph_t::trans_storage_t tr_t;
+    g.sort_transitions_([](const tr_t& lhs, const tr_t& rhs)
+			{ return lhs.src < rhs.src; });
+    g.chain_transitions_();
+  }
+}

src/tgbaalgos/randomize.hh

@@ -0,0 +1,37 @@
+// -*- coding: utf-8 -*-
+// Copyright (C) 2014 Laboratoire de Recherche et
+// Développement de l'Epita (LRDE).
+//
+// This file is part of Spot, a model checking library.
+//
+// Spot is free software; you can redistribute it and/or modify it
+// under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 3 of the License, or
+// (at your option) any later version.
+//
+// Spot is distributed in the hope that it will be useful, but WITHOUT
+// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+// or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
+// License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+#ifndef SPOT_TGBAALGOS_RANDOMIZE_HH
+# define SPOT_TGBAALGOS_RANDOMIZE_HH
+
+#include "tgba/tgbagraph.hh"
+
+namespace spot
+{
+  /// \brief Randomize a TGBA
+  ///
+  /// Make a random permutation of the state, and of the transitions
+  /// leaving this state.
+  SPOT_API void
+  randomize(tgba_digraph_ptr& aut,
+	    bool randomize_states = true,
+	    bool randomize_transitions = true);
+}
+
+#endif // SPOT_TGBAALGOS_RANDOMGRAPH_HH

src/tgbatest/Makefile.am

@@ -104,6 +104,7 @@ TESTS = \
   degenid.test \
   degenlskip.test \
   kv.test \
+  randomize.test \
   lbttparse.test \
   scc.test \
   sccsimpl.test \

src/tgbatest/randomize.test

@@ -0,0 +1,82 @@
+#!/bin/sh
+# -*- coding: utf-8 -*-
+# Copyright (C) 2014 Laboratoire de Recherche et Développement de
+# l'Epita (LRDE).
+#
+# This file is part of Spot, a model checking library.
+#
+# Spot is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# Spot is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+# or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
+# License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+. ./defs
+
+set -e
+
+ltl2tgba=../../bin/ltl2tgba
+autfilt=../../bin/autfilt
+
+$ltl2tgba --hoa 'Ga | Gb | Gc | Gd' > out
+
+cat >expected <<EOF
+HOA: v1
+name: "Ga | Gb | Gc | Gd"
+States: 5
+Start: 0
+AP: 4 "a" "b" "c" "d"
+acc-name: all
+Acceptance: 0 t
+properties: trans-labels explicit-labels state-acc
+--BODY--
+State: 0
+[0] 1
+[1] 2
+[2] 3
+[3] 4
+State: 1
+[0] 1
+State: 2
+[1] 2
+State: 3
+[2] 3
+State: 4
+[3] 4
+--END--
+EOF
+
+diff out expected
+
+# The seed and formula where chosen so that these four outputs are
+# different.
+run 0 $autfilt --seed=1 --dot out > 1.dot
+run 0 $autfilt --seed=1 --dot --randomize=t out > 2.dot
+run 0 $autfilt --seed=1 --dot --randomize=s out > 3.dot
+run 0 $autfilt --seed=1 --dot --randomize=st out > 4.dot
+
+cmp 1.dot 2.dot && exit 1
+cmp 1.dot 3.dot && exit 1
+cmp 2.dot 3.dot && exit 1
+cmp 2.dot 4.dot && exit 1
+cmp 3.dot 4.dot && exit 1
+
+# A second run should produce the same output
+$autfilt --seed=1 --dot out > 1b.dot
+$autfilt --seed=1 --dot --randomize=t out > 2b.dot
+$autfilt --seed=1 --dot --randomize=s out > 3b.dot
+$autfilt --seed=1 --dot --randomize=st out > 4b.dot
+diff 1.dot 1b.dot
+diff 2.dot 2b.dot
+diff 3.dot 3b.dot
+diff 4.dot 4b.dot
+
+$autfilt --randomize=foo out 2>stderr && exit 1
+grep "unknown argument for --randomize: 'f'" stderr