mail: implement struct command.

* NEWS, doc/texinfo/programs.texi: Document struct command.
* mail/struct.c: New file.
* mail/Makefile.am (mail_SOURCES): Add struct.c
* mail/decode.c (fprint_msgset, mime_descend): New functions.
Rewrite the rest using mime_descend.
* mail/mail.h (mail_struct): New function.
(MDHINT_SELECTED_HEADERS): New define.
(struct mime_descend_closure, mime_descend_fn): New types.
(mime_descend): New proto.
(util_get_content_type): Get two arguments.
* mail/table.c (mail_command_table): Add st[ruct].
* mail/util.c (util_get_content_type): Get two arguments.
All callers updated.
(util_get_hdr_value): use mu_header_aget_value_unfold and
mu_rtrim_class.

-GNU mailutils NEWS -- history of user-visible changes. 2009-07-12
+GNU mailutils NEWS -- history of user-visible changes. 2009-07-13
 Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 
 2008, 2009 Free Software Foundation, Inc.
 See the end of file for copying conditions.
@@ -53,6 +53,15 @@ is also allowed.
 The -F option (record outgoing messages in a file named after the
 first recipient) is implemented.
 
+** struct command
+
+The st[ruct] command allows to list message MIME structures, e.g.:
+
+& struct 2
+2[1]  text/plain                 513
+2[2]  application/octal-stream  247K
+2[3]  text/x-diff                31K
+
 ** error locations
 
 Diagnostic messages issued while processing `source' command

@@ -2878,6 +2878,7 @@ Displays current mailbox summary. E.g.:
 @kyindex Print, mail command
 @kyindex Type, mail command
 @kyindex decode, mail command
+@kyindex struct, mail command
 @kyindex top, mail command
 @kyindex pipe, mail command
 @kyindex |, mail command
@@ -2926,6 +2927,21 @@ defaults to five.
 Pipe the contents of specified messages through @var{shell-command}. If
 @var{shell-command} is empty but the string variable @code{cmd} is set,
 the value of this variable is used as a command name.
+@item struct [@var{msglist}]
+Prints the @acronym{MIME} structure of each message from
+@var{msglist}. Empty @var{msglist} means current message.
+
+Example:
+
+@smallexample
+@cartouche
+& struct 2
+2      multipart/mixed            14k
+2[1]   text/plain                 296
+2[2]   application/octet-stream    5k
+2[3]   text/x-diff                31k
+@end cartouche
+@end smallexample
 @end table
 
 @node Marking Messages

@@ -84,6 +84,7 @@ mail_SOURCES = \
  shell.c\
  size.c\
  source.c\
+ struct.c\
  summary.c\
  table.c\
  tag.c\

@@ -33,7 +33,8 @@ struct decode_closure
 
 static int print_stream (mu_stream_t, FILE *);
 static int display_message (mu_message_t, msgset_t *msgset, void *closure);
-static int display_message0 (mu_message_t, const msgset_t *, int);
+static int display_submessage (struct mime_descend_closure *closure,
+			       void *data);
 static int get_content_encoding (mu_header_t hdr, char **value);
 static void run_metamail (const char *mailcap, mu_message_t mesg);
 
@@ -59,12 +60,20 @@ display_message (mu_message_t mesg, msgset_t *msgset, void *arg)
 {
   struct decode_closure *closure = arg;
   mu_attribute_t attr = NULL;
-
+  struct mime_descend_closure mclos;
+  
   mu_message_get_attribute (mesg, &attr);
   if (mu_attribute_is_deleted (attr))
     return 1;
 
-  display_message0 (mesg, msgset, closure->select_hdr);
+  mclos.hints = closure->select_hdr ? MDHINT_SELECTED_HEADERS : 0;
+  mclos.msgset = msgset;
+  mclos.message = mesg;
+  mclos.type = NULL;
+  mclos.encoding = NULL;
+  mclos.parent = NULL;
+
+  mime_descend (&mclos, display_submessage, NULL);
 
   /* Mark enclosing message as read */
   if (mu_mailbox_get_message (mbox, msgset->msg_part[0], &mesg) == 0)
@@ -112,9 +121,23 @@ display_headers (FILE *out, mu_message_t mesg,
     }
 }
 
+size_t
+fprint_msgset (FILE *fp, const msgset_t *msgset)
+{
+  int i;
+  size_t n = 0;
+  
+  n = fprintf (fp, "%d", msgset->msg_part[0]);
+  for (i = 1; i < msgset->npart; i++)
+    n += fprintf (fp, "[%d", msgset->msg_part[i]);
+  for (i = 1; i < msgset->npart; i++)
+    n += fprintf (fp, "]");
+  return n;
+}
+
 static void
 display_part_header (FILE *out, const msgset_t *msgset,
-		     char *type, char *encoding)
+		     const char *type, const char *encoding)
 {
   int size = util_screen_columns () - 3;
   unsigned int i;
@@ -124,11 +147,8 @@ display_part_header (FILE *out, const msgset_t *msgset,
     fputc ('-', out);
   fputc ('+', out);
   fputc ('\n', out);
-  fprintf (out, _("| Message=%d"), msgset->msg_part[0]);
-  for (i = 1; i < msgset->npart; i++)
-    fprintf (out, "[%d", msgset->msg_part[i]);
-  for (i = 1; i < msgset->npart; i++)
-    fprintf (out, "]");
+  fprintf (out, "%s", _("| Message="));
+  fprint_msgset (out, msgset);
   fprintf (out, "\n");
 
   fprintf (out, _("| Type=%s\n"), type);
@@ -140,38 +160,49 @@ display_part_header (FILE *out, const msgset_t *msgset,
   fputc ('\n', out);
 }
 
-static int
-display_message0 (mu_message_t mesg, const msgset_t *msgset,
-		  int select_hdr)
+int
+mime_descend (struct mime_descend_closure *closure,
+	      mime_descend_fn fun, void *data)
 {
+  int status = 0;
   size_t nparts = 0;
   mu_header_t hdr = NULL;
   char *type;
   char *encoding;
   int ismime = 0;
-  char *tmp;
+  struct mime_descend_closure subclosure;
 
-  mu_message_get_header (mesg, &hdr);
-  util_get_content_type (hdr, &type);
+  mu_message_get_header (closure->message, &hdr);
+  util_get_content_type (hdr, &type, NULL);
   get_content_encoding (hdr, &encoding);
 
-  mu_message_is_multipart (mesg, &ismime);
+  closure->type = type;
+  closure->encoding = encoding;
+  
+  subclosure.hints = 0;
+  subclosure.parent = closure;
+  
+  mu_message_is_multipart (closure->message, &ismime);
   if (ismime)
     {
       unsigned int j;
-      
-      mu_message_get_num_parts (mesg, &nparts);
+
+      mu_message_get_num_parts (closure->message, &nparts);
 
       for (j = 1; j <= nparts; j++)
 	{
 	  mu_message_t message = NULL;
 
-	  if (mu_message_get_part (mesg, j, &message) == 0)
+	  if (mu_message_get_part (closure->message, j, &message) == 0)
 	    {
-	      msgset_t *set = msgset_expand (msgset_dup (msgset),
+	      msgset_t *set = msgset_expand (msgset_dup (closure->msgset),
 					     msgset_make_1 (j));
-	      display_message0 (message, set, 0);
+	      subclosure.msgset = set;
+	      subclosure.message = message;
+	      status = mime_descend (&subclosure, fun, data);
 	      msgset_free (set);
+	      if (status)
+		break;
 	    }
 	}
     }
@@ -179,14 +210,36 @@ display_message0 (mu_message_t mesg, const msgset_t *msgset,
     {
       mu_message_t submsg = NULL;
 
-      if (mu_message_unencapsulate (mesg, &submsg, NULL) == 0)
-	display_message0 (submsg, msgset, select_hdr);
+      if (mu_message_unencapsulate (closure->message, &submsg, NULL) == 0)
+	{
+	  subclosure.hints = MDHINT_SELECTED_HEADERS;
+	  subclosure.msgset = closure->msgset;
+	  subclosure.message = submsg;
+	  status = mime_descend (&subclosure, fun, data);
+	}
     }
-  else if (mailvar_get (&tmp, "metamail", mailvar_type_string, 0) == 0)
+  else
+    status = fun (closure, data);
+
+  closure->type = NULL;
+  closure->encoding = NULL;
+  
+  free (type);
+  free (encoding);
+
+  return status;
+}
+
+static int
+display_submessage (struct mime_descend_closure *closure, void *data)
+{
+  char *tmp;
+  
+  if (mailvar_get (&tmp, "metamail", mailvar_type_string, 0) == 0)
     {
       /* If `metamail' is set to a string, treat it as command line
 	 of external metamail program. */
-      run_metamail (tmp, mesg);
+      run_metamail (tmp, closure->message);
     }
   else
     {
@@ -197,19 +250,20 @@ display_message0 (mu_message_t mesg, const msgset_t *msgset,
       mu_stream_t stream = NULL;
       mu_header_t hdr = NULL;
       
-      mu_message_get_body (mesg, &body);
-      mu_message_get_header (mesg, &hdr);
+      mu_message_get_body (closure->message, &body);
+      mu_message_get_header (closure->message, &hdr);
       mu_body_get_stream (body, &b_stream);
 
       /* Can we decode.  */
-      if (mu_filter_create(&d_stream, b_stream, encoding,
-			MU_FILTER_DECODE, MU_STREAM_READ) == 0)
+      if (mu_filter_create(&d_stream, b_stream, closure->encoding,
+			   MU_FILTER_DECODE, MU_STREAM_READ) == 0)
 	stream = d_stream;
       else
 	stream = b_stream;
-
-      display_part_header (ofile, msgset, type, encoding);
-
+      
+      display_part_header (ofile, closure->msgset,
+			   closure->type, closure->encoding);
+      
       /* If `metamail' is set to true, enable internal mailcap
 	 support */
       if (mailvar_get (NULL, "metamail", mailvar_type_boolean, 0) == 0)
@@ -225,33 +279,31 @@ display_message0 (mu_message_t mesg, const msgset_t *msgset,
 	  builtin_display = display_stream_mailcap (NULL, stream, hdr, no_ask,
 						    interactive, 0, debug);
 	}
-
+      
       if (builtin_display)
 	{
 	  size_t lines = 0;
 	  int pagelines = util_get_crt ();
 	  FILE *out;
 	  
-	  mu_message_lines (mesg, &lines);
+	  mu_message_lines (closure->message, &lines);
 	  if (pagelines && lines > pagelines)
 	    out = popen (getenv ("PAGER"), "w");
 	  else
 	    out = ofile;
-
-	  display_headers (out, mesg, msgset, select_hdr);
-
+	  
+	  display_headers (out, closure->message, closure->msgset,
+			   closure->hints & MDHINT_SELECTED_HEADERS);
+	  
 	  print_stream (stream, out);
-
+	  
 	  if (out != ofile)
 	    pclose (out);
 	}
       if (d_stream)
 	mu_stream_destroy (&d_stream, NULL);
     }
-
-  free (type);
-  free (encoding);
-
+  
   return 0;
 }
 

@@ -242,6 +242,7 @@ extern int mail_eq (int argc, char **argv);	/* command = */
 extern int mail_setenv (int argc, char **argv);
 extern int mail_envelope (int argc, char **argv);
 extern int print_envelope (msgset_t *mspec, mu_message_t msg, void *data);
+extern int mail_struct (int argc, char **argv);
 
 extern int if_cond (void);
 
@@ -307,6 +308,27 @@ extern int msgset_member (msgset_t *set, size_t n);
 extern msgset_t *msgset_negate (msgset_t *set);
 extern size_t msgset_count (msgset_t *set);
 
+
+#define MDHINT_SELECTED_HEADERS 0x1
+
+struct mime_descend_closure
+{
+  int hints;
+  const msgset_t *msgset;
+  mu_message_t message;
+  const char *type;
+  const char *encoding;
+  const struct mime_descend_closure *parent;
+};
+
+typedef int (*mime_descend_fn) (struct mime_descend_closure *closure,
+				void *data);
+
+extern int mime_descend (struct mime_descend_closure *closure,
+			 mime_descend_fn fun, void *data);
+
+
+
 extern int util_do_command (const char *cmd, ...) MU_PRINTFLIKE(1,2);
 
 extern int util_foreach_msg (int argc, char **argv, int flags,
@@ -369,7 +391,7 @@ extern int util_tempfile (char **namep);
 extern void util_msgset_iterate (msgset_t *msgset, 
                                  int (*fun) (mu_message_t, msgset_t *, void *), 
                                  void *closure);
-extern int util_get_content_type (mu_header_t hdr, char **value);
+extern int util_get_content_type (mu_header_t hdr, char **value, char **args);
 extern int util_get_hdr_value (mu_header_t hdr, const char *name, char **value);
 extern int util_merge_addresses (char **addr_str, const char *value);
 extern int util_header_expand (mu_header_t *hdr);
@@ -383,6 +405,8 @@ void util_mark_read (mu_message_t msg);
 
 const char *util_url_to_string (mu_url_t url);
 
+size_t fprint_msgset (FILE *fp, const msgset_t *msgset);
+
 int is_address_field (const char *name);
 
 extern int ml_got_interrupt (void);

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2009 Free Software Foundation, Inc.
+
+   GNU Mailutils 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, or (at your option)
+   any later version.
+
+   GNU Mailutils 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 GNU Mailutils.  If not, see <http://www.gnu.org/licenses/>. */
+
+#include "mail.h"
+
+#define PART_WIDTH 8
+
+static int
+show_part (struct mime_descend_closure *closure, void *data)
+{
+  size_t width;
+  size_t size = 0;
+  
+  width = fprint_msgset (ofile, closure->msgset);
+  for (; width < 5; width++)
+    fputc (' ', ofile);
+    
+  fprintf (ofile, " %-25s", closure->type);
+
+  mu_message_size (closure->message, &size);
+  if (size < 1024)
+    fprintf (ofile, " %4lu", (unsigned long) size);
+  else if (size < 1024*1024)
+    fprintf (ofile, "%4luK", (unsigned long) size / 1024);
+  else
+    fprintf (ofile, "%4luM", (unsigned long) size / 1024 / 1024);
+
+  fprintf (ofile, "\n");
+  return 0;
+}
+
+static int
+show_struct (msgset_t *msgset, mu_message_t msg, void *data)
+{
+  struct mime_descend_closure mclos;
+  
+  mclos.hints = 0;
+  mclos.msgset = msgset;
+  mclos.message = msg;
+  mclos.type = NULL;
+  mclos.encoding = NULL;
+  mclos.parent = NULL;
+  
+  mime_descend (&mclos, show_part, NULL);
+
+    /* Mark enclosing message as read */
+  if (mu_mailbox_get_message (mbox, msgset->msg_part[0], &msg) == 0)
+    util_mark_read (msg);
+
+  return 0;
+}
+
+int
+mail_struct (int argc, char **argv)
+{
+  return util_foreach_msg (argc, argv, MSG_NODELETED|MSG_SILENT,
+			   show_struct, NULL);
+}

@@ -136,6 +136,8 @@ static const struct mail_command_entry mail_command_table[] = {
     mail_size, msglist_compl },
   { "so",	"source",	"so[urce] file",		0,
     mail_source, NULL },
+  { "st",       "struct",       "st[ruct] [msglist]",           0,
+    mail_struct, NULL },
   { "su",	"summary",	"su[mmary]",			0,
     mail_summary, no_compl },
   { "T",	"Type",		"T[ype] [msglist]",		0,

@@ -793,7 +793,7 @@ util_descend_subparts (mu_message_t mesg, msgset_t *msgset, mu_message_t *part)
       mu_header_t hdr = NULL;
 
       mu_message_get_header (mesg, &hdr);
-      util_get_content_type (hdr, &type);
+      util_get_content_type (hdr, &type, NULL);
       if (mu_c_strncasecmp (type, "message/rfc822", strlen (type)) == 0)
 	{
 	  if (mu_message_unencapsulate (mesg, &submsg, NULL))
@@ -839,12 +839,12 @@ util_msgset_iterate (msgset_t *msgset,
 	return;
 
       if (util_descend_subparts (mesg, msgset, &mesg) == 0)
-	  (*fun)(mesg, msgset, closure);
+	(*fun) (mesg, msgset, closure);
     }
 }
 
 int
-util_get_content_type (mu_header_t hdr, char **value)
+util_get_content_type (mu_header_t hdr, char **value, char **args)
 {
   char *type = NULL;
   util_get_hdr_value (hdr, MU_HEADER_CONTENT_TYPE, &type);
@@ -854,6 +854,17 @@ util_get_content_type (mu_header_t hdr, char **value)
 	free (type);
       type = strdup ("text/plain"); /* Default.  */
     }
+  else
+    {
+      char *p;
+      p = strchr (type, ';');
+      if (p)
+	{
+	  *p++ = 0;
+	  if (args)
+	    *args = p;
+	}
+    }
   *value = type;
   return 0;
 }
@@ -861,16 +872,9 @@ util_get_content_type (mu_header_t hdr, char **value)
 int
 util_get_hdr_value (mu_header_t hdr, const char *name, char **value)
 {
-  int status = mu_header_aget_value (hdr, name, value);
+  int status = mu_header_aget_value_unfold (hdr, name, value);
   if (status == 0)
-    {
-      /* Remove the newlines.  */
-      char *nl;
-      while ((nl = strchr (*value, '\n')) != NULL)
-	{
-	  *nl = ' ';
-	}
-    }
+    mu_rtrim_class (*value, MU_CTYPE_SPACE);
   return status;
 }