Bugfixes in AMD code.

* libproto/include/amd.h (new_msg_file_name): Add an argument indicating
whether an actual expunsion is going to take place, as opposed to saving
message flags.
* libproto/maildir/mbox.c (maildir_new_message_name): Sync with above changes.
* libproto/mh/mbox.c (_mh_new_message_name): Likewise.
* mailbox/amd.c (_amd_message_save): Handle unlink requests
(new_msg_file_name returning NULL name). This avoids creating temp files.
(amd_expunge): Remove messages that have had MU_ATTRIBUTE_DELETED on mailbox
open, if the underlying mailbox implementation allows that.

@@ -72,7 +72,7 @@ struct _amd_data
 			      const mu_message_t);
   void (*msg_free) (struct _amd_message *);
   int (*cur_msg_file_name) (struct _amd_message *, char **);	
-  int (*new_msg_file_name) (struct _amd_message *, int attr_flags, char **);
+  int (*new_msg_file_name) (struct _amd_message *, int, int, char **);
   int (*scan0)     (mu_mailbox_t mailbox, size_t msgno, size_t *pcount,
 		    int do_notify);
   int (*mailbox_size) (mu_mailbox_t mailbox, mu_off_t *psize);

@@ -342,14 +342,13 @@ maildir_cur_message_name (struct _amd_message *amsg, char **pname)
 }
 
 static int
-maildir_new_message_name (struct _amd_message *amsg, int flags, char **pname)
+maildir_new_message_name (struct _amd_message *amsg, int flags, int expunge,
+			  char **pname)
 {
   struct _maildir_message *msg = (struct _maildir_message *) amsg;
-  if (flags & MU_ATTRIBUTE_DELETED)
+  if (expunge && (flags & MU_ATTRIBUTE_DELETED))
     {
-      /* Force amd.c to unlink the file.
-	 FIXME: We could also add a 'T' info to it. Should
-	 we have an option deciding which approach to take? */
+      /* Force amd.c to unlink the file. */
       *pname = NULL;
     }
   else if (strcmp (msg->dir, CURSUF) == 0)

@@ -126,7 +126,9 @@ _mh_cur_message_name (struct _amd_message *amsg, char **pname)
 /* Return newfilename for the message.
    NOTE: Allocates memory. */
 static int
-_mh_new_message_name (struct _amd_message *amsg, int flags, char **pname)
+_mh_new_message_name (struct _amd_message *amsg, int flags,
+		      int expunge MU_ARG_UNUSED,
+		      char **pname)
 {
   int status = 0;
   struct _mh_message *mhm = (struct _mh_message *) amsg;

@@ -600,7 +600,7 @@ _amd_message_save (struct _amd_data *amd, struct _amd_message *mhm,
 		   int expunge)
 {
   mu_stream_t stream = NULL;
-  char *name = NULL, *buf = NULL, *msg_name;
+  char *name = NULL, *buf = NULL, *msg_name, *old_name;
   size_t n, off = 0;
   size_t bsize;
   size_t nlines, nbytes;
@@ -618,9 +618,27 @@ _amd_message_save (struct _amd_data *amd, struct _amd_message *mhm,
   if (status)
     return status;
 
+  status = amd->new_msg_file_name (mhm, mhm->attr_flags, expunge, &msg_name);
+  if (status)
+    return status;
+  if (!msg_name)
+    {
+      /* Unlink the original file */
+      char *old_name;
+      status = amd->cur_msg_file_name (mhm, &old_name);
+      free (msg_name);
+      if (status == 0 && unlink (old_name))
+	status = errno;
+      free (old_name);
+      return status;
+    }      
+    
   fp = _amd_tempfile (mhm->amd, &name);
   if (!fp)
+    {
+      free (msg_name);
       return errno;
+    }
 
   /* Try to allocate large buffer */
   for (; bsize > 1; bsize /= 2)
@@ -628,7 +646,12 @@ _amd_message_save (struct _amd_data *amd, struct _amd_message *mhm,
       break;
 
   if (!bsize)
+    {
+      unlink (name);
+      free (name);
+      free (msg_name);
       return ENOMEM;
+    }
 
   /* Copy flags */
   mu_message_get_header (msg, &hdr);
@@ -724,10 +747,6 @@ _amd_message_save (struct _amd_data *amd, struct _amd_message *mhm,
   free (buf);
   fclose (fp);
 
-  status = amd->new_msg_file_name (mhm, mhm->attr_flags, &msg_name);
-  if (status == 0)
-    {
-      char *old_name;
   status = amd->cur_msg_file_name (mhm, &old_name);
   if (status == 0)
     {
@@ -759,7 +778,6 @@ _amd_message_save (struct _amd_data *amd, struct _amd_message *mhm,
       mhm->orig_flags = mhm->attr_flags;
     }
   free (msg_name);
-    }
   free (name);
 
   return status;
@@ -1065,8 +1083,6 @@ amd_expunge (mu_mailbox_t mailbox)
       
       if (mhm->attr_flags & MU_ATTRIBUTE_DELETED)
 	{
-	  if (!(mhm->orig_flags & MU_ATTRIBUTE_DELETED))
-	    {
 	  int rc;
 	  char *old_name;
 	  char *new_name;
@@ -1074,7 +1090,8 @@ amd_expunge (mu_mailbox_t mailbox)
 	  rc = amd->cur_msg_file_name (mhm, &old_name);
 	  if (rc)
 	    return rc;
-	      rc = amd->new_msg_file_name (mhm, mhm->attr_flags, &new_name);
+	  rc = amd->new_msg_file_name (mhm, mhm->attr_flags, 1,
+				       &new_name);
 	  if (rc)
 	    {
 	      free (old_name);
@@ -1083,15 +1100,21 @@ amd_expunge (mu_mailbox_t mailbox)
 
 	  if (new_name)
 	    {
+	      /* FIXME: It may be a good idea to have a capability flag
+		 in struct _amd_data indicating that no actual removal
+		 is needed (e.g. for traditional MH). It will allow to
+		 bypass lots of no-op code here. */
+	      if (strcmp (old_name, new_name))
 		/* Rename original message */
 		rename (old_name, new_name);
-		  free (new_name);
 	    }
 	  else
 	    /* Unlink original file */
 	    unlink (old_name);
+	  
 	  free (old_name);
-	    }
+	  free (new_name);
+
 	  _amd_message_delete (amd, mhm);
 	  updated = 1;
 	  /* Do not increase i! */