freebsd-skq/bin/sh/parser.h
jilles bd55770c94 sh: Do parameter expansion before printing PS4 (set -x).
The function name expandstr() and the general idea of doing this kind of
expansion by treating the text as a here document without end marker is from
dash.

All variants of parameter expansion and arithmetic expansion also work (the
latter is not required by POSIX but it does not take extra code and many
other shells also allow it).

Command substitution is prevented because I think it causes too much code to
be re-entered (for example creating an unbounded recursion of trace lines).

Unfortunately, our LINENO is somewhat crude, otherwise PS4='$LINENO+ ' would
be quite useful.
2011-06-09 23:12:23 +00:00

86 lines
3.4 KiB
C

/*-
* 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.
* 4. 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
* $FreeBSD$
*/
/* control characters in argument strings */
#define CTLESC '\300'
#define CTLVAR '\301'
#define CTLENDVAR '\371'
#define CTLBACKQ '\372'
#define CTLQUOTE 01 /* ored with CTLBACKQ code if in quotes */
/* CTLBACKQ | CTLQUOTE == '\205' */
#define CTLARI '\374'
#define CTLENDARI '\375'
#define CTLQUOTEMARK '\376'
#define CTLQUOTEEND '\377' /* only for ${v+-...} */
/* 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 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} */
#define VSERROR 0xb /* Syntax error, issue when expanded */
/*
* 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.
*/
extern int tokpushback;
#define NEOF ((union node *)&tokpushback)
extern int whichprompt; /* 1 == PS1, 2 == PS2 */
extern const char *const parsekwd[];
union node *parsecmd(int);
void fixredir(union node *, const char *, int);
int goodname(const char *);
int isassignment(const char *);
char *getprompt(void *);
const char *expandstr(char *);