048f26671a
The code is inspired by NetBSD sh somewhat, but different because we
preserve the old Almquist/Bourne/Korn ability to have an unquoted part in a
quoted ${v+word}. For example, "${v-"*"}" expands to $v as a single field if
v is set, but generates filenames otherwise.
Note that this is the only place where we split text literally from the
script (the similar ${v=word} assigns to v and then expands $v). The parser
must now add additional markers to allow the expansion code to know whether
arbitrary characters in substitutions are quoted.
Example:
for i in ${$+a b c}; do echo $i; done
Exp-run done by: pav (with some other sh(1) changes)
84 lines
3.4 KiB
C
84 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 '\201'
|
|
#define CTLVAR '\202'
|
|
#define CTLENDVAR '\203'
|
|
#define CTLBACKQ '\204'
|
|
#define CTLQUOTE 01 /* ored with CTLBACKQ code if in quotes */
|
|
/* CTLBACKQ | CTLQUOTE == '\205' */
|
|
#define CTLARI '\206'
|
|
#define CTLENDARI '\207'
|
|
#define CTLQUOTEMARK '\210'
|
|
#define CTLQUOTEEND '\211' /* 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 *);
|
|
char *getprompt(void *);
|