/*      $NetBSD: eval.h,v 1.25 2026/05/20 00:50:00 kre Exp $    */

/*-
 * Copyright (c) 1991, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Kenneth Almquist.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      @(#)eval.h      8.2 (Berkeley) 5/4/95
 */

extern const char *commandname; /* currently executing command */
extern int exitstatus;          /* exit status of last command */
extern int back_exitstatus;     /* exit status of backquoted command */
extern struct strlist *cmdenviron;  /* environment for builtin command */

        /*
         * Note: this will be set in both parent and child, during the
         * vfork() process, in the parent it MUST be cleared at any time
         * a signal might arrive (ie: signals must be blocked before setting
         * it, and it must cleared again before releasing the block).   In
         * the child it will be set when the fork occurs, and then needs to
         * be cleared sometime before the child would want to receive and
         * process a signal that has been set for it to catch (ie: no big
         * hurry, but fairly soon - it happens once the trap[] array is
         * reset to allow child traps to be set).
         *
         * Aside from inside evalcommand() which uses it to properly process
         * vfork(), its value should only ever be tested in signal handlers
         * - that is its sole (externally visible) purpose.
         */
extern volatile int vforking;   /* Set if a vfork() is in progress */


struct backcmd {                /* result of evalbackcmd */
        int fd;                 /* file descriptor to read from */
        char *buf;              /* buffer */
        int nleft;              /* number of chars in buffer */
        struct job *jp;         /* job structure for command */
};

void evalstring(const char *, int);
union node;     /* BLETCH for ansi C */
void evaltree(union node *, int);
void evalbackcmd(union node *, struct backcmd *);

const char *syspath(void);

/* in_function returns nonzero if we are currently evaluating a function */
int in_function(void);          /* return non-zero, if evaluating a function */

/* reasons for skipping commands (see comment on breakcmd routine) */
enum skipstate {
      SKIPNONE  = 0,    /* not skipping */
      SKIPBREAK,        /* break */
      SKIPCONT,         /* continue */
      SKIPFUNC,         /* return in a function */
      SKIPFILE          /* return in a dot command */
};

struct skipsave {
        enum skipstate state;   /* skipping or not */
        int count;              /* when break or continue, how many */
};

enum skipstate current_skipstate(void);
void save_skipstate(struct skipsave *);
void restore_skipstate(const struct skipsave *);
void stop_skipping(void);       /* reset internal skipping state to SKIPNONE */
int set_dot_funcnest(int);

/*
 * Only for use by reset() in init.c!
 */
void reset_eval(void);

/* flags in argument to evaltree */
#define EV_EXIT         0x01    /* exit after evaluating tree */
#define EV_TESTED       0x02    /* exit status is checked; ignore -e flag */
#define EV_BACKCMD      0x04    /* command executing within back quotes */