Add Debug class to libmu_cpp.

* include/mailutils/cpp/debug.h, libmu_cpp/debug.cc: New files.
* examples/cpp/mimetest.cc, examples/cpp/sfrom.cc, libmu_cpp/header.cc,
include/mailutils/cpp/header.h: Accept default header value if missing.

@@ -74,7 +74,12 @@ main (int argc, char **argv)
 
   MailboxDefault mbox (argv[i]);
   
-  /* Debugging trace. FIXME: ADD MISSING */
+  /* Debugging trace. */
+  if (debug)
+    {
+      Debug debug = mbox.get_debug ();
+      debug.set_level (MU_DEBUG_LEVEL_UPTO (MU_DEBUG_PROT));
+    }
 
   /* Open the mailbox for reading only. */
   mbox.open ();
@@ -89,7 +94,7 @@ main (int argc, char **argv)
 
     cout << "Message: " << i << endl;
     cout << "From: " << hdr[MU_HEADER_FROM] << endl;
-    cout << "Subject: " << hdr[MU_HEADER_SUBJECT] << endl;
+    cout << "Subject: " << hdr.get_value (MU_HEADER_SUBJECT, "[none]") << endl;
     cout << "Number of parts in message - " << msg.get_num_parts () << endl;
     cout << "Total message size - "
 	 << msg.size () << "/" << msg.lines () << endl;
@@ -162,7 +167,7 @@ message_display_parts (Message& msg, int indent)
 
 	  Header hdr = part.get_header ();
 	  string from = hdr[MU_HEADER_FROM];
-	  string subject = hdr[MU_HEADER_SUBJECT];
+	  string subject = hdr.get_value (MU_HEADER_SUBJECT, "[none]");
 
 	  cout << setw (indent) << setfill (' ')
 	       << "Encapsulated message : " << from << "\t" << subject << endl;

@@ -43,7 +43,7 @@ int main (int argc, char* argv[])
       Message msg = mbox[msgno];
       Header hdr = msg.get_header ();
       cout << hdr[MU_HEADER_FROM] << " "
-	   << hdr[MU_HEADER_SUBJECT] << endl;
+	   << hdr.get_value (MU_HEADER_SUBJECT, "[none]") << endl;
     }
 
     mbox.close ();

@@ -20,6 +20,7 @@ MU_CXX_INCLUDES = \
  address.h\
  attribute.h\
  body.h\
+ debug.h\
  error.h\
  filter.h\
  header.h\

+/*
+   GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2009 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library; if not, write to the
+   Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+   Boston, MA 02110-1301 USA
+*/
+
+#ifndef _MUCPP_DEBUG_H
+#define _MUCPP_DEBUG_H
+
+#include <string>
+#include <mailutils/debug.h>
+
+namespace mailutils
+{
+
+class Debug
+{
+ protected:
+  mu_debug_t debug;
+
+ public:
+  Debug ();
+  Debug (const mu_debug_t);
+
+  void set_level (const mu_log_level_t level);
+};
+
+}
+
+#endif // not _MUCPP_DEBUG_H
+

@@ -37,6 +37,7 @@ class Header
   Header (const mu_header_t);
 
   std::string get_value (const std::string& name);
+  std::string get_value (const std::string& name, const std::string& def);
   size_t size ();
   size_t lines ();
 

@@ -22,6 +22,7 @@
 #define _MUCPP_MAILBOX_H
 
 #include <mailutils/mailbox.h>
+#include <mailutils/cpp/debug.h>
 #include <mailutils/cpp/message.h>
 
 namespace mailutils
@@ -37,6 +38,8 @@ class MailboxBase
   void open (int flag);
   void close ();
 
+  Debug& get_debug ();
+
   size_t messages_count ();
   Message& get_message (size_t num);
 

@@ -27,6 +27,7 @@ libmu_cpp_la_SOURCES = \
  address.cc\
  attribute.cc\
  body.cc\
+ debug.cc\
  filter.cc\
  header.cc\
  iterator.cc\

+/*
+   GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2009 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library; if not, write to the
+   Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+   Boston, MA 02110-1301 USA
+*/
+
+#include <mailutils/cpp/debug.h>
+#include <mailutils/cpp/error.h>
+#include <errno.h>
+
+using namespace mailutils;
+
+//
+// Debug
+//
+
+Debug :: Debug ()
+{
+  this->debug = NULL;
+}
+
+Debug :: Debug (const mu_debug_t debug)
+{
+  if (debug == 0)
+    throw Exception ("Debug::Debug", EINVAL);
+
+  this->debug = debug;
+}
+
+void
+Debug :: set_level (const mu_log_level_t level)
+{
+  int status = mu_debug_set_level (debug, level);
+  if (status)
+    throw Exception ("Debug::set_level", status);
+}
+

@@ -30,6 +30,7 @@ using namespace mailutils;
 
 Header :: Header ()
 {
+  this->hdr = NULL;
 }
 
 Header :: Header (const mu_header_t hdr)
@@ -54,6 +55,22 @@ Header :: get_value (const std::string& name)
   return val;
 }
 
+std::string
+Header :: get_value (const std::string& name, const std::string& def)
+{
+  char* c_val;
+
+  int status = mu_header_aget_value (hdr, name.c_str (), &c_val);
+  if (status == MU_ERR_NOENT)
+    return std::string (def);
+  else if (status)
+    throw Exception ("Header::get_value", status);
+
+  std::string val (c_val);
+  free (c_val);
+  return val;
+}
+
 size_t
 Header :: size ()
 {

@@ -19,7 +19,6 @@
 */
 
 #include <mailutils/cpp/mailbox.h>
-#include <mailutils/cpp/message.h>
 #include <mailutils/cpp/error.h>
 #include <errno.h>
 
@@ -53,6 +52,18 @@ MailboxBase :: close ()
     throw Exception ("MailboxBase::close", status);
 }
 
+Debug&
+MailboxBase :: get_debug ()
+{
+  mu_debug_t c_dbg;
+
+  int status = mu_mailbox_get_debug (mbox, &c_dbg);
+  if (status)
+    throw Exception ("MailboxBase::get_debug", status);
+
+  return *new Debug (c_dbg);
+}
+
 size_t
 MailboxBase :: messages_count ()
 {