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+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2006 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 2, 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, write to the Free Software
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+   MA 02110-1301 USA */
+
+#define obstack_chunk_alloc malloc
+#define obstack_chunk_free free
+#include <obstack.h>
+
+typedef struct       /* A string object type */
+{
+  int size;          /* Allocated size or 0 for static storage */
+  char *ptr;         /* Actual data */
+}
+strobj_t;
+
+#define strobj_ptr(p) ((p)->ptr ? (p)->ptr : "")
+#define strobj_len(p) (strobj_is_null(p) ? 0 : strlen((p)->ptr))
+#define strobj_is_null(p) ((p)->ptr == NULL)
+#define strobj_is_static(p) ((p)->size == 0)
+
+struct mh_machine
+{
+  strobj_t reg_str;         /* String register */
+  int reg_num;              /* Numeric register */
+
+  strobj_t arg_str;         /* String argument */
+  long arg_num;             /* Numeric argument */
+  
+  size_t pc;                /* Program counter */
+  size_t progsize;          /* Size of allocated program*/
+  mh_instr_t *prog;         /* Program itself */
+  int stop;                 /* Stop execution immediately */
+
+  struct obstack stk;       /* Output buffer */
+  size_t width;             /* Output buffer width */
+  size_t ind;               /* Output buffer index */
+
+  mu_list_t addrlist;       /* The list of email addresses output this far */
+  int fmtflags;             /* Current formatting flags */
+  
+  mu_message_t message;     /* Current message */
+  size_t msgno;             /* Its number */
+};
+
+void strobj_free (strobj_t *obj);
+void strobj_create (strobj_t *lvalue, char *str);
+void strobj_set (strobj_t *lvalue, char *str);
+void strobj_assign (strobj_t *lvalue, strobj_t *rvalue);
+void strobj_copy (strobj_t *lvalue, strobj_t *rvalue);
+void strobj_realloc (strobj_t *obj, size_t length);