Main header for mh functions.

+/* 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.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+#include <argp.h>
+#include <mh_getopt.h>
+
+#include <string.h>
+
+#include <mailutils/parse822.h>
+#include <mailutils/mailbox.h>
+#include <mailutils/message.h>
+#include <mailutils/header.h>
+#include <mailutils/body.h>
+#include <mailutils/registrar.h>
+#include <mailutils/list.h>
+#include <mailutils/iterator.h>
+#include <mailutils/address.h>
+#include <mailutils/mutil.h>
+#include <mailutils/filter.h>
+
+#define MH_FMT_RALIGN 0x1000
+#define MH_FMT_ZEROPAD 0x2000
+#define MH_WIDTH_MASK  0x0fff
+
+enum mh_opcode
+{
+  /* 0. Stop. Format: mhop_stop */
+  mhop_stop,
+  /* 1. Branch.
+     Format: mhop_branch offset */
+  mhop_branch,
+  /* 2. Assign to numeric register
+     Format: mhop_num_asgn number */
+  mhop_num_asgn,
+  /* 3. Assign to string register
+     Format: mhop_str_asgn length string */
+  mhop_str_asgn,
+  /* 4. Numeric arg follows.
+     Format: mhop_num_arg number */
+  mhop_num_arg,
+  /* 5. String arg follows.
+     Format: mhop_str_arg length string */
+  mhop_str_arg,
+  /* 6. Branch if reg_num is zero.
+     Format: mhop_num_branch dest-off */
+  mhop_num_branch,
+  /* 7. Branch if reg_str is zero.
+     Format: mhop_str_branch dest-off */
+  mhop_str_branch,
+  /* 8. Set str to the value of the header component
+     Format: mhop_header */
+  mhop_header,
+
+  /* 9. Read message body contents into str.
+     Format: mhop_body */
+  mhop_body,
+  
+  /* 10. Call a function.
+     Format: mhop_call function-pointer */
+  mhop_call,
+
+  /* 11. assign reg_num to arg_num */
+  mhop_num_to_arg,
+
+  /* 12. assign reg_str to arg_str */
+  mhop_str_to_arg,
+
+  /* 13. Convert arg_str to arg_num */
+  mhop_str_to_num,
+  
+  /* 14. Convert arg_num to arg_str */
+  mhop_num_to_str,
+
+  /* 15. Print reg_num */
+  mhop_num_print,
+
+  /* 16. Print reg_str */
+  mhop_str_print,
+
+  /* 17. Set format specification.
+     Format: mhop_fmtspec number */
+  mhop_fmtspec
+};    
+
+enum mh_type
+{
+  mhtype_none,
+  mhtype_num,
+  mhtype_str
+};
+
+typedef int mh_opcode_t;
+typedef struct mh_format mh_format_t;
+struct mh_format
+{
+  size_t progsize;          /* Size of allocated program*/
+  mh_opcode_t *prog;        /* Program itself */
+};
+struct mh_machine;
+typedef void (*mh_builtin_fp)(struct mh_machine *);
+
+typedef struct mh_builtin mh_builtin_t;
+
+struct mh_builtin
+{
+  char *name;
+  mh_builtin_fp fun;
+  int type;
+  int argtype;
+  int optarg;
+};
+
+void mh_init (void);
+int mh_format (mh_format_t *fmt, message_t msg, size_t msgno,
+	       char *buffer, size_t bufsize);
+int mh_format_parse (char *format_str, mh_format_t *fmt);
+void mh_format_free (mh_format_t *fmt);
+mh_builtin_t *mh_lookup_builtin (char *name, int *rest);
+
+void mh_error(const char *fmt, ...);
+
+void *xmalloc (size_t);
+void *xrealloc (void *, size_t);
+