Implementation of scan command.

+/* GNU mailutils - a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc.
+
+   This program 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, or (at your option)
+   any later version.
+
+   This program 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 this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
+
+/* MH scan command */
+
+#include <mh.h>
+#ifdef HAVE_TERMCAP_H
+# include <termcap.h>
+#endif
+
+const char *argp_program_version = "scan (" PACKAGE ") " VERSION;
+const char *argp_program_bug_address = "<bug-mailutils@gnu.org>";
+static char doc[] = "GNU MH scan";
+static char args_doc[] = "";
+
+/* GNU options */
+static struct argp_option options[] = {
+  {"folder",  'f', "FOLDER", 0, "Specify folder to scan"},
+  {"clear",   'c', "BOOL",   OPTION_ARG_OPTIONAL, "Clear screen after displaying the list"},
+  {"form",    'F', "FILE",   0, "Read format from given file"},
+  {"format",  't', "FORMAT", 0, "Use this format string"},
+  {"header",  'H', "BOOL",   OPTION_ARG_OPTIONAL, "Display header"},
+  {"width",   'w', "NUMBER", 0, "Set output width"},
+  {"reverse", 'r', "BOOL",   OPTION_ARG_OPTIONAL, "List messages in reverse order"},
+  {"file",    'i', "FILE",   0, "[Not yet implemented]"},
+  
+  {"license", 'l', 0,        0, "Display software license", -1},
+
+  { "\nUse -help switch to obtain the list of traditional MH options. ", 0, 0, OPTION_DOC, "" },
+  
+  { 0 }
+};
+
+/* Traditional MH options */
+struct mh_option mh_option[] = {
+  {"clear",   1,  'c', MH_OPT_BOOL},
+  {"form",    4,  'F', MH_OPT_ARG, "formatfile"},
+  {"format",  5,  't', MH_OPT_ARG, "string"},
+  {"header",  3,  'H', MH_OPT_BOOL},
+  {"width",   1,  'w', MH_OPT_ARG, "number"},
+  {"reverse", 1,  'r', MH_OPT_BOOL},
+  {"file",    4,  'i', MH_OPT_ARG, "file"},
+  { 0 }
+};
+
+static char *scan_folder = "inbox";
+static int clear;
+static char *formfile;
+static char *format_str = 
+"%4(msg)%<(cur)+%| %>%<{replied}-%?{encrypted}E%| %>"
+"%02(mon{date})/%02(mday{date})"
+"%<{date} %|*%>"
+"%<(mymbox{from})%<{to}To:%14(friendly{to})%>%>"
+"%<(zero)%17(friendly{from})%>"
+"  %{subject}%<{body}<<%{body}>>%>";
+
+static int width = 80;
+static int reverse;
+
+static mh_format_t format;
+
+void list_message (mailbox_t mbox, size_t msgno, char *bp, size_t width);
+int scan (mailbox_t mbox);
+
+static int
+opt_handler (int key, char *arg, void *unused)
+{
+  switch (key)
+    {
+    case 'f': 
+      scan_folder = arg;
+      break;
+      
+    case 'c':
+      clear = arg[0] == 'y';
+      break;
+      
+    case 'F':
+      formfile = arg;
+      break;
+      
+    case 't':
+      format_str = arg;
+      break;
+      
+    case 'H':
+      clear = arg[0] == 'y';
+      break;
+      
+    case 'w':
+      width = strtoul (arg, NULL, 0);
+      if (!width)
+	{
+	  mh_error ("Invalid width");
+	  exit (1);
+	}
+      break;
+      
+    case 'r':
+      reverse = arg[0] == 'y';
+      break;
+      
+    case 'i':
+      mh_error ("'i' is not yet implemented.");
+      break;
+      
+    case 'l':
+      mh_license (argp_program_version);
+      break;
+      
+    default:
+      return 1;
+    }
+  return 0;
+}
+
+void
+set_folder ()
+{
+  scan_folder = mu_tilde_expansion (scan_folder, "/", NULL);
+  if (strchr (scan_folder, '/') == NULL)
+    {
+      char *p = mu_get_homedir ();
+      asprintf (&scan_folder, "mh:%s/Mail/%s", p, scan_folder);
+      if (!scan_folder)
+	{
+	  mh_error ("low memory");
+	  exit (1);
+	}
+    }
+  else if (strchr (scan_folder, ':') == NULL)
+    {
+      char *p;
+      p = xmalloc (strlen (scan_folder) + 4);
+      strcat (strcpy (p, "mh:"), scan_folder);
+      scan_folder = p;
+    }
+}
+
+int
+main (int argc, char **argv)
+{
+  mailbox_t mbox = NULL;
+
+  mh_init ();
+  mh_argp_parse (argc, argv, options, mh_option, args_doc, doc,
+		 opt_handler, NULL);
+
+  set_folder ();
+  if (mh_format_parse (format_str, &format))
+    {
+      mh_error ("Bad format string");
+      exit (1);
+    }
+
+  if (mailbox_create_default (&mbox, scan_folder))
+    {
+      mh_error ("Can't create mailbox %s: %s", scan_folder, strerror (errno));
+      exit (1);
+    }
+
+  if (mailbox_open (mbox, MU_STREAM_READ))
+    {
+      mh_error ("Can't open mailbox %s: %s", scan_folder, strerror (errno));
+      exit (1);
+    }
+
+  return scan (mbox);
+}
+
+#ifdef HAVE_TERMCAP_H
+/* A subroutine for tputs */
+int
+putstdout(char c)
+{
+  return putc(c, stdout);
+}
+#endif
+
+void
+clear_screen ()
+{
+#ifdef HAVE_TERMCAP_H
+  if (clear)
+    {
+      char termcap_buf[1024];
+      char *buffer;
+      char *termname;
+      
+      if ((termname = getenv("TERM")) == NULL)
+	  /* No terminal; Try ansi */
+	termname = "ansi";
+      
+      if (tgetent(termcap_buf, termname) != 1)
+	fprintf (stdout, "\f");
+      else
+	{
+	  char *clr = tgetstr ("cl", &buffer);
+	  if (clr)
+	    tputs(clr, 1, (int (*)())putstdout);
+	  else
+	    fprintf (stdout, "\f");
+	}
+    }
+#endif
+}
+
+int
+scan (mailbox_t mbox)
+{
+  size_t i, total;
+  char *buffer;
+
+  buffer = xmalloc (width);
+  
+  mailbox_messages_count (mbox, &total);
+
+  if (reverse)
+    for (i = total; i >= 1; i--)
+      list_message (mbox, i, buffer, width);
+  else
+    for (i = 1; i <= total; i++)
+      list_message (mbox, i, buffer, width);
+  clear_screen ();
+  return 0;
+}
+
+void
+list_message (mailbox_t mbox, size_t msgno, char *buffer, size_t width)
+{
+  message_t msg;
+
+  buffer[0] = 0;
+  mailbox_get_message (mbox, msgno, &msg);
+  mh_format (&format, msg, msgno, buffer, width);
+  printf ("%s\n", buffer);
+}