Rewrite parseopt help routines using wordwrap streams

* include/mailutils/stream.h (MU_IOCTL_WORDWRAP_SET_NEXT_MARGIN)
(MU_IOCTL_WORDWRAP_GET_OFFSET): New opcodes.
* libmailutils/stream/wordwrap.c (_wordwrap_flush_line): Replace
whitespace-only lines with single newline on output.
(_wordwrap_flush): Fix condition.
(set_margin): Bugfix.
(_wordwrap_ctl): Handle new opcodes.

* include/mailutils/cli.h (mu_version_func): Change signature.
* include/mailutils/opt.h (mu_parseopt) <po_help_hook>
<po_version_hook>: Change signature.
(mu_parseopt_fmt_text): Remove.
(mu_option_describe_options, mu_program_help)
(mu_program_usage): Change signature.
(mu_program_version): New prototype.
* libmailutils/cli/cli.c (mu_version_func): Take mu_stream_t as
2nd argument.  Use mu_stream_printf for output.
(extra_help_hook): Likewise.
* libmailutils/opt/help.c: Rewrite using wordwrap streams.
* libmailutils/opt/opt.c (fn_help, fn_usage, fn_version): Update.
* libmailutils/tests/parseopt.c (version_hook): Write to mu_stream_t.

* libmailutils/tests/parseopt_help00.at: Fix expected output.
* libmailutils/tests/parseopt_help01.at: Likewise.
* libmailutils/tests/parseopt_help02.at: Likewise.
* libmailutils/tests/parseopt_help03.at: Likewise.
* libmailutils/tests/parseopt_help04.at: Likewise.
* libmailutils/tests/parseopt_help05.at: Likewise.
* libmailutils/tests/parseopt_help06.at: Likewise.
* libmailutils/tests/parseopt_help07.at: Likewise.
* libmailutils/tests/parseopt_help08.at: Likewise.
* libmailutils/tests/parseopt_help09.at: Likewise.
* libmailutils/tests/parseopt_help10.at: Likewise.
* libmailutils/tests/parseopt_help11.at: Likewise.

@@ -50,7 +50,7 @@ struct mu_cli_setup
 				  errors */
 };
 
-void mu_version_func (struct mu_parseopt *po, FILE *stream);
+void mu_version_func (struct mu_parseopt *po, mu_stream_t stream);
 void mu_cli (int argc, char **argv, struct mu_cli_setup *setup,
 	     char **capa, void *data,
 	     int *ret_argc, char ***ret_argv);

@@ -131,9 +131,8 @@ struct mu_parseopt
   char const *po_package_url;
   char const *po_extra_info;
 
-  /* FIXME: should these take mu_stream_t ?*/
-  void (*po_help_hook) (struct mu_parseopt *po, FILE *stream); 
-  void (*po_version_hook) (struct mu_parseopt *po, FILE *stream);
+  void (*po_help_hook) (struct mu_parseopt *po, mu_stream_t stream); 
+  void (*po_version_hook) (struct mu_parseopt *po, mu_stream_t stream);
   
   /* Output data */
   int po_ind;                      /* Index of the next option */
@@ -169,11 +168,12 @@ int mu_parseopt_apply (struct mu_parseopt *p);
 void mu_parseopt_free (struct mu_parseopt *p);
 
 unsigned mu_parseopt_getcolumn (const char *name);
-void mu_parseopt_fmt_text (const char *text, size_t col);
 
-void mu_option_describe_options (struct mu_option **optbuf, size_t optcnt);
-void mu_program_help (struct mu_parseopt *p);
-void mu_program_usage (struct mu_parseopt *p);
+void mu_option_describe_options (mu_stream_t str,
+				 struct mu_option **optbuf, size_t optcnt);
+void mu_program_help (struct mu_parseopt *p, mu_stream_t str);
+void mu_program_usage (struct mu_parseopt *p, mu_stream_t str);
+void mu_program_version (struct mu_parseopt *po, mu_stream_t str);
 
 void mu_option_set_value (struct mu_parseopt *po, struct mu_option *opt,
 			  char const *arg);

@@ -208,10 +208,12 @@ enum mu_buffer_type
   ((n) == MU_TRANSPORT_INPUT || (n) == MU_TRANSPORT_OUTPUT)
 
 /* Word wrapper streams */
-#define MU_IOCTL_WORDWRAP_GET_MARGIN  0
-#define MU_IOCTL_WORDWRAP_SET_MARGIN  1   
-#define MU_IOCTL_WORDWRAP_MOVE_MARGIN 2
-  
+#define MU_IOCTL_WORDWRAP_GET_MARGIN      0
+#define MU_IOCTL_WORDWRAP_SET_MARGIN      1  
+#define MU_IOCTL_WORDWRAP_MOVE_MARGIN     2
+#define MU_IOCTL_WORDWRAP_SET_NEXT_MARGIN 3
+#define MU_IOCTL_WORDWRAP_GET_OFFSET      4
+
 struct mu_nullstream_pattern
 {
   char *pattern;

@@ -53,40 +53,37 @@ const char mu_version_copyright[] =
   "Copyright %s 2007-2016 Free Software Foundation, inc.";
 
 void
-mu_version_func (struct mu_parseopt *po, FILE *stream)
+mu_version_func (struct mu_parseopt *po, mu_stream_t stream)
 {
 #ifdef GIT_DESCRIBE
-  fprintf (stream, "%s (%s) %s [%s]\n",
-	   mu_program_name, PACKAGE_NAME, PACKAGE_VERSION, GIT_DESCRIBE);
+  mu_stream_printf (stream, "%s (%s) %s [%s]\n",
+		    mu_program_name, PACKAGE_NAME, PACKAGE_VERSION,
+		    GIT_DESCRIBE);
 #else
-  fprintf (stream, "%s (%s) %s\n", mu_program_name,
-	   PACKAGE_NAME, PACKAGE_VERSION);
+  mu_stream_printf (stream, "%s (%s) %s\n", mu_program_name,
+		    PACKAGE_NAME, PACKAGE_VERSION);
 #endif
   /* TRANSLATORS: Translate "(C)" to the copyright symbol
      (C-in-a-circle), if this symbol is available in the user's
      locale.  Otherwise, do not translate "(C)"; leave it as-is.  */
-  fprintf (stream, mu_version_copyright, _("(C)"));
-  fputs (_("\
+  mu_stream_printf (stream, mu_version_copyright, _("(C)"));
+  mu_stream_printf (stream, _("\
 \n\
 License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>\nThis is free software: you are free to change and redistribute it.\n\
 There is NO WARRANTY, to the extent permitted by law.\n\
 \n\
-"),
-	 stream);
+"));
 }
 
 static char gnu_general_help_url[] =
   N_("General help using GNU software: <http://www.gnu.org/gethelp/>");
 
 static void
-extra_help_hook (struct mu_parseopt *po, FILE *stream)
+extra_help_hook (struct mu_parseopt *po, mu_stream_t stream)
 {
   struct mu_cfg_parse_hints *hints = po->po_data;
   struct mu_cli_setup *setup = hints->data;
-  char *extra_doc = _(setup->prog_extra_doc);
-  /* FIXME: mu_parseopt help output should get FILE * argument */
-  mu_parseopt_fmt_text (extra_doc, 0);
-  fputc ('\n', stdout);
+  mu_stream_printf (stream, "%s\n", _(setup->prog_extra_doc));
 }
 
 static void

@@ -24,6 +24,7 @@
 #include <mailutils/opt.h>
 #include <mailutils/nls.h>
 #include <mailutils/errno.h>
+#include <mailutils/stdstream.h>
 
 #define EXIT_SUCCESS 0
 #define EXIT_ERROR   1
@@ -78,7 +79,7 @@ sort_group (struct mu_option **optbuf, size_t start)
 static void
 fn_help (struct mu_parseopt *po, struct mu_option *opt, char const *unused)
 {
-  mu_program_help (po);
+  mu_program_help (po, mu_strout);
   exit (EXIT_SUCCESS);
 }
 
@@ -86,14 +87,14 @@ fn_help (struct mu_parseopt *po, struct mu_option *opt, char const *unused)
 static void
 fn_usage (struct mu_parseopt *po, struct mu_option *opt, char const *unused)
 {
-  mu_program_usage (po);
+  mu_program_usage (po, mu_strout);
   exit (EXIT_SUCCESS);
 }
 
 static void
 fn_version (struct mu_parseopt *po, struct mu_option *opt, char const *unused)
 {
-  po->po_version_hook (po, stdout);
+  mu_program_version (po, mu_strout);
   exit (EXIT_SUCCESS);
 }
 

@@ -88,7 +88,7 @@ _wordwrap_flush_line (struct mu_wordwrap_stream *str, int lookahead)
 	}
     }
 
-  while (length > 0 && mu_isblank (str->buffer[length - 1]))
+  while (length > 0 && mu_isspace (str->buffer[length - 1]))
     length--;
   
   if (length == 0 || str->buffer[length - 1] != '\n')
@@ -147,7 +147,7 @@ static int
 _wordwrap_flush (mu_stream_t stream)
 {
   struct mu_wordwrap_stream *str = (struct mu_wordwrap_stream *)stream;
-  if (str->offset)
+  if (str->offset > str->left_margin)
     _wordwrap_flush_line (str, 0);
   return mu_stream_flush (str->transport);
 }
@@ -177,18 +177,19 @@ set_margin (mu_stream_t stream, unsigned lmargin, int off)
   
   if (lmargin >= str->right_margin)
     return EINVAL;
-  if (lmargin < str->offset)
+
+  str->left_margin = lmargin;
+  if (lmargin < str->offset ||
+      (str->offset > 0 && str->buffer[str->offset - 1] == '\n'))
     {
-      str->left_margin = lmargin;
       _wordwrap_flush (stream);
     }
   else if (lmargin > str->offset)
     {
-      memset (str->buffer + str->offset, ' ',
-	      lmargin - str->offset);
-      str->left_margin = lmargin;
+      memset (str->buffer + str->offset, ' ', lmargin - str->offset);
       str->offset = lmargin;
     }
+      
   return 0;
 }
 
@@ -217,12 +218,30 @@ _wordwrap_ctl (mu_stream_t stream, int code, int opcode, void *arg)
 	  else
 	    return set_margin (stream, *(unsigned*)arg, 0);
 
+	case MU_IOCTL_WORDWRAP_SET_NEXT_MARGIN:
+	  if (!arg)
+	    return EINVAL;
+	  else
+	    {
+	      unsigned marg = *(unsigned*)arg;
+	      if (marg >= str->right_margin)
+		return EINVAL;
+	      str->left_margin = marg;
+	    }
+	  break;
+	  
 	case MU_IOCTL_WORDWRAP_MOVE_MARGIN:
 	  if (!arg)
 	    return EINVAL;
 	  else
 	    return set_margin (stream, str->offset, *(int*)arg);
-	  
+
+	case MU_IOCTL_WORDWRAP_GET_OFFSET:
+	  if (!arg)
+	    return EINVAL;
+	  *(unsigned*)arg = str->offset;
+	  break;
+
 	default:
 	  return EINVAL;
 	}

@@ -64,9 +64,9 @@ struct mu_option group_b[] = {
 struct mu_option *optv[] = { group_a, group_b, NULL };
 
 static void
-version_hook (struct mu_parseopt *po, FILE *fp)
+version_hook (struct mu_parseopt *po, mu_stream_t str)
 {
-  fputs ("version hook called\n", fp);
+  mu_stream_printf (str, "version hook called\n");
 }
 
 #define S(s) ((s)?(s):"(null)")

@@ -30,8 +30,8 @@ parseopt --help
   -x                         short-only option
 
  Group B
-  -F, --find=VALUE           find VALUE
   -d, -v, --debug, --verbose another option
+  -F, --find=VALUE           find VALUE
   -j, --jobs=N               sets numeric value
 
   -?, --help                 give this help list

@@ -21,8 +21,8 @@ PARSEOPT_DEFAULT
 parseopt --usage
 ],
 [0],
-[[Usage: parseopt [-advx?] [-f FILE] [-F VALUE] [-j N] [-o FILE] [--all]
+[[Usage: parseopt [-advx?] [-f FILE] [-F VALUE] [-j N] [-o[FILE]] [--all]
             [--debug] [--file=FILE] [--find=VALUE] [--help] [--jobs=N]
-            [--optional=FILE] [--usage] [--verbose]
+            [--optional[=FILE]] [--usage] [--verbose]
 ]])
 AT_CLEANUP

@@ -30,8 +30,8 @@ MU_PARSEOPT_PROG_NAME=newname parseopt --help
   -x                         short-only option
 
  Group B
-  -F, --find=VALUE           find VALUE
   -d, -v, --debug, --verbose another option
+  -F, --find=VALUE           find VALUE
   -j, --jobs=N               sets numeric value
 
   -?, --help                 give this help list

@@ -31,8 +31,8 @@ Tests option parsing
   -x                         short-only option
 
  Group B
-  -F, --find=VALUE           find VALUE
   -d, -v, --debug, --verbose another option
+  -F, --find=VALUE           find VALUE
   -j, --jobs=N               sets numeric value
 
   -?, --help                 give this help list

@@ -30,8 +30,8 @@ MU_PARSEOPT_PROG_ARGS="SOME MORE ARGS" parseopt --help
   -x                         short-only option
 
  Group B
-  -F, --find=VALUE           find VALUE
   -d, -v, --debug, --verbose another option
+  -F, --find=VALUE           find VALUE
   -j, --jobs=N               sets numeric value
 
   -?, --help                 give this help list

@@ -30,8 +30,8 @@ MU_PARSEOPT_BUG_ADDRESS='gray@gnu.org' parseopt --help
   -x                         short-only option
 
  Group B
-  -F, --find=VALUE           find VALUE
   -d, -v, --debug, --verbose another option
+  -F, --find=VALUE           find VALUE
   -j, --jobs=N               sets numeric value
 
   -?, --help                 give this help list

@@ -30,8 +30,8 @@ MU_PARSEOPT_PACKAGE_NAME='GNU Mailutils' MU_PARSEOPT_PACKAGE_URL='http://mailuti
   -x                         short-only option
 
  Group B
-  -F, --find=VALUE           find VALUE
   -d, -v, --debug, --verbose another option
+  -F, --find=VALUE           find VALUE
   -j, --jobs=N               sets numeric value
 
   -?, --help                 give this help list

@@ -37,8 +37,8 @@ Tests option parsing
   -x                         short-only option
 
  Group B
-  -F, --find=VALUE           find VALUE
   -d, -v, --debug, --verbose another option
+  -F, --find=VALUE           find VALUE
   -j, --jobs=N               sets numeric value
 
   -?, --help                 give this help list

@@ -31,8 +31,8 @@ ARGP_HELP_FMT=dup-args,no-dup-args-note,short-opt-col=1,opt-doc-col=32,header-co
  -x                             short-only option
 
           Group B
- -F VALUE, --find=VALUE         find VALUE
  -d, -v, --debug, --verbose     another option
+ -F VALUE, --find=VALUE         find VALUE
  -j N, --jobs=N                 sets numeric value
 
  -?,  --help                    give this help list

@@ -23,7 +23,7 @@ ARGP_HELP_FMT=rmargin=62,usage-indent=1\
 ],
 [0],
 [[Usage: parseopt [-advx?] [-f FILE] [-F VALUE] [-j N]
- [-o FILE] [--all] [--debug] [--file=FILE] [--find=VALUE]
- [--help] [--jobs=N] [--optional=FILE] [--usage] [--verbose]
+ [-o[FILE]] [--all] [--debug] [--file=FILE] [--find=VALUE]
+ [--help] [--jobs=N] [--optional[=FILE]] [--usage] [--verbose]
 ]])
 AT_CLEANUP

@@ -21,8 +21,8 @@ PARSEOPT_DEFAULT
 MU_PARSEOPT_VERSION_HOOK=1 parseopt --usage
 ],
 [0],
-[[Usage: parseopt [-advVx?] [-f FILE] [-F VALUE] [-j N] [-o FILE] [--all]
+[[Usage: parseopt [-advVx?] [-f FILE] [-F VALUE] [-j N] [-o[FILE]] [--all]
             [--debug] [--file=FILE] [--find=VALUE] [--help] [--jobs=N]
-            [--optional=FILE] [--usage] [--verbose] [--version]
+            [--optional[=FILE]] [--usage] [--verbose] [--version]
 ]])
 AT_CLEANUP

@@ -30,8 +30,8 @@ MU_PARSEOPT_VERSION_HOOK=1 parseopt --help
   -x                         short-only option
 
  Group B
-  -F, --find=VALUE           find VALUE
   -d, -v, --debug, --verbose another option
+  -F, --find=VALUE           find VALUE
   -j, --jobs=N               sets numeric value
 
   -?, --help                 give this help list