parser.h

操作系统源代码

/*-
 * Copyright (c) 1991 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 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	5.1 (Berkeley) 3/7/91
 */

/* 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 */

/* variable substitution byte (follows CTLVAR) */
#define VSTYPE 07		/* type of variable substitution */
#define VSNUL 040		/* colon--treat the empty string as unset */
#define VSQUOTE 0100		/* inside double quotes--suppress splitting */

/* values of VSTYPE field */
#define VSNORMAL 1		/* normal variable:  $var or ${var} */
#define VSMINUS 2		/* ${var-text} */
#define VSPLUS 3		/* ${var+text} */
#define VSQUESTION 4		/* ${var?message} */
#define VSASSIGN 5		/* ${var=text} */


/*
 * 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)


#ifdef __STDC__
union node *parsecmd(int);
int goodname(char *);
#else
union node *parsecmd();
int goodname();
#endif