Factor the %-formating machinery.

* src/misc/formater.hh: New file.
* src/misc/Makefile.am: Add it.
* src/tgbaalgos/stats.cc, src/tgbaalgos/stats.hh: Use it.

src/misc/formater.hh

@@ -0,0 +1,195 @@
+// -*- coding: utf-8 -*-
+// Copyright (C) 2012 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 2 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 Spot; see the file COPYING.  If not, write to the Free
+// Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+// 02111-1307, USA.
+
+#ifndef SPOT_SRC_MISC_FORMATER_HH
+#define SPOT_SRC_MISC_FORMATER_HH
+
+#include <iostream>
+#include <string>
+#include <vector>
+
+namespace spot
+{
+  class printable
+  {
+  public:
+    ~printable()
+    {
+    }
+    virtual void
+    print(std::ostream&, const char*) const = 0;
+  };
+
+
+  template <class T>
+  class printable_value: public printable
+  {
+  protected:
+    T val_;
+  public:
+    operator T() const
+    {
+      return val_;
+    }
+
+    printable_value&
+    operator=(const T& new_val)
+    {
+      val_ = new_val;
+      return *this;
+    }
+
+    virtual void
+    print(std::ostream& os, const char*) const
+    {
+      os << val_;
+    }
+  };
+
+  /// The default callback simply writes "%c".
+  class printable_id: public printable
+  {
+  public:
+    virtual void
+    print(std::ostream& os, const char* x) const
+    {
+      os << '%' << *x;
+    }
+  };
+
+  /// Called by default for "%%" and "%\0".
+  class printable_percent: public printable
+  {
+  public:
+    virtual void
+    print(std::ostream& os, const char*) const
+    {
+      os << '%';
+    }
+  };
+
+
+  class formater
+  {
+    printable_id id;
+    printable_percent percent;
+  public:
+
+    formater()
+      : has_(256), call_(256, &id)
+    {
+      call_['%'] = call_[0] = &percent;
+    }
+
+    /// Collect the %-sequences occurring in \a fmt.
+    void
+    prime(const char* fmt)
+    {
+      for (const char* pos = fmt; *pos; ++pos)
+	if (*pos == '%')
+	  {
+	    char c = *++pos;
+	    has_[c] = true;
+	    if (!c)
+	      break;
+	  }
+    }
+
+    /// Collect the %-sequences occurring in \a fmt.
+    void
+    prime(const std::string& fmt)
+    {
+      prime(fmt.c_str());
+    }
+
+    /// Whether %c occurred in the primed formats.
+    bool
+    has(char c) const
+    {
+      return has_[c];
+    }
+
+    /// Declare a callback function for %c.
+    void
+    declare(char c, const printable* f)
+    {
+      call_[c] = f;
+    }
+
+    /// Remember where to output any string.
+    void
+    set_output(std::ostream& output)
+    {
+      output_ = &output;
+    }
+
+    /// Expand the %-sequences in \a fmt, write the result on \a output_.
+    std::ostream&
+    format(const char* fmt)
+    {
+      for (const char* pos = fmt; *pos; ++pos)
+	if (*pos != '%')
+	  {
+	    *output_ << *pos;
+	  }
+	else
+	  {
+	    char c = *++pos;
+	    call_[c]->print(*output_, pos);
+	    if (!c)
+	      break;
+	  }
+      return *output_;
+    }
+
+    /// Expand the %-sequences in \a fmt, write the result on \a output.
+    std::ostream&
+    format(std::ostream& output, const char* fmt)
+    {
+      set_output(output);
+      return format(fmt);
+    }
+
+    /// Expand the %-sequences in \a fmt, write the result on \a output_.
+    std::ostream&
+    format(const std::string& fmt)
+    {
+      return format(fmt.c_str());
+    }
+
+    /// Expand the %-sequences in \a fmt, write the result on \a output.
+    std::ostream&
+    format(std::ostream& output, const std::string& fmt)
+    {
+      return format(output, fmt.c_str());
+    }
+
+  private:
+    std::vector<bool> has_;
+    std::vector<const printable*> call_;
+  protected:
+    std::ostream* output_;
+    const char* pos_;
+  };
+
+}
+
+#endif // SPOT_SRC_MISC_FORMATER_HH