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/* $NetBSD: parser.h,v 1.27 2018/12/11 13:31:20 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.
*
* @(#)parser.h 8.3 (Berkeley) 5/4/95
*/
/* control characters in argument strings */
#define CTL_FIRST '\201' /* first 'special' character */
#define CTLESC '\201' /* escape next character */
#define CTLVAR '\202' /* variable defn */
#define CTLENDVAR '\203'
#define CTLBACKQ '\204'
#define CTLQUOTE 01 /* ored with CTLBACKQ code if in quotes */
/* CTLBACKQ | CTLQUOTE == '\205' */
#define CTLARI '\206' /* arithmetic expression */
#define CTLENDARI '\207'
#define CTLQUOTEMARK '\210'
#define CTLQUOTEEND '\211' /* only inside ${...} */
#define CTLNONL '\212' /* The \n in a deleted \ \n sequence */
/* pure concidence that (CTLNONL & 0x7f) == '\n' */
#define CTLCNL '\213' /* A $'\n' - newline not counted */
#define CTL_LAST '\213' /* last 'special' character */
/* variable substitution byte (follows CTLVAR) */
#define VSTYPE 0x0f /* type of variable substitution */
#define VSNUL 0x10 /* colon--treat the empty string as unset */
#define VSLINENO 0x20 /* expansion of $LINENO, the line number
follows immediately */
#define VSPATQ 0x40 /* ensure correct pattern quoting in ${x#pat} */
#define VSQUOTE 0x80 /* inside double quotes--suppress splitting */
/* values of VSTYPE field */
#define VSNORMAL 0x1 /* normal variable: $var or ${var} */
#define VSMINUS 0x2 /* ${var-text} */
#define VSPLUS 0x3 /* ${var+text} */
#define VSQUESTION 0x4 /* ${var?message} */
#define VSASSIGN 0x5 /* ${var=text} */
#define VSTRIMLEFT 0x6 /* ${var#pattern} */
#define VSTRIMLEFTMAX 0x7 /* ${var##pattern} */
#define VSTRIMRIGHT 0x8 /* ${var%pattern} */
#define VSTRIMRIGHTMAX 0x9 /* ${var%%pattern} */
#define VSLENGTH 0xa /* ${#var} */
union node *parsecmd(int);
void fixredir(union node *, const char *, int);
int goodname(const char *);
int isassignment(const char *);
const char *getprompt(void *);
const char *expandstr(char *, int);
const char *expandenv(char *);
struct HereDoc;
union node;
struct nodelist;
struct parse_state {
struct HereDoc *ps_heredoclist; /* list of here documents to read */
int ps_parsebackquote; /* nonzero inside backquotes */
int ps_doprompt; /* if set, prompt the user */
int ps_needprompt; /* true if interactive at line start */
int ps_lasttoken; /* last token read */
int ps_tokpushback; /* last token pushed back */
char *ps_wordtext; /* text of last word returned by readtoken */
int ps_checkkwd; /* word expansion flags, see below */
struct nodelist *ps_backquotelist; /* list of cmdsubs to process */
union node *ps_redirnode; /* node for current redirect */
struct HereDoc *ps_heredoc; /* current heredoc << beign parsed */
int ps_quoteflag; /* set if (part) of token was quoted */
int ps_startlinno; /* line # where last token started */
int ps_funclinno; /* line # of the current function */
int ps_elided_nl; /* count of \ \n pairs we have seen */
};
/*
* The parser references the elements of struct parse_state quite
* frequently - they used to be simple globals, so one memory ref
* per access, adding an indirect through global ptr would not be
* nice. The following gross hack allows most of that cost to be
* avoided, by allowing the compiler to understand that the global
* pointer is in fact constant in any function, and so its value can
* be cached, rather than needing to be fetched every time in case
* some other called function has changed it.
*
* The rule to make this work is that any function that wants
* to alter the global must restore it before it returns (and thus
* must have an error trap handler). That means that the struct
* used for the new parser state can be a local in that function's
* stack frame, it never needs to be malloc'd.
*/
union parse_state_p {
struct parse_state *const c_current_parser;
struct parse_state * v_current_parser;
};
extern union parse_state_p psp;
#define current_parser (psp.c_current_parser)
/*
* Perhaps one day emulate "static" by moving most of these definitions into
* parser.c ... (only checkkwd & tokpushback are used outside parser.c,
* and only in init.c as a RESET activity)
*/
#define tokpushback (current_parser->ps_tokpushback)
#define checkkwd (current_parser->ps_checkkwd)
#define noalias (current_parser->ps_noalias)
#define heredoclist (current_parser->ps_heredoclist)
#define parsebackquote (current_parser->ps_parsebackquote)
#define doprompt (current_parser->ps_doprompt)
#define needprompt (current_parser->ps_needprompt)
#define lasttoken (current_parser->ps_lasttoken)
#define wordtext (current_parser->ps_wordtext)
#define backquotelist (current_parser->ps_backquotelist)
#define redirnode (current_parser->ps_redirnode)
#define heredoc (current_parser->ps_heredoc)
#define quoteflag (current_parser->ps_quoteflag)
#define startlinno (current_parser->ps_startlinno)
#define funclinno (current_parser->ps_funclinno)
#define elided_nl (current_parser->ps_elided_nl)
/*
* Values that can be set in checkkwd
*/
#define CHKKWD 0x01 /* turn word into keyword (if it is) */
#define CHKNL 0x02 /* ignore leading \n's */
#define CHKALIAS 0x04 /* lookup words as aliases and ... */
/*
* NEOF is returned by parsecmd when it encounters an end of file. It
* must be distinct from NULL, so we use the address of a variable that
* happens to be handy.
*/
#define NEOF ((union node *)&psp)
#ifdef DEBUG
extern int parsing;
#endif
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