main.c

来自「<B>Digital的Unix操作系统VAX 4.2源码</B>」· C语言 代码 · 共 169 行

#ifndef lint
static char *sccsid = "@(#)main.c	4.1	ULTRIX	7/17/90";
#endif lint

/************************************************************************
 *									*
 *			Copyright (c) 1989 by				*
 *		Digital Equipment Corporation, Maynard, MA		*
 *			All rights reserved.				*
 *									*
 *   This software is furnished under a license and may be used and	*
 *   copied  only  in accordance with the terms of such license and	*
 *   with the  inclusion  of  the  above  copyright  notice.   This	*
 *   software  or  any  other copies thereof may not be provided or	*
 *   otherwise made available to any other person.  No title to and	*
 *   ownership of the software is hereby transferred.			*
 *									*
 *   This software is  derived  from  software  received  from  the	*
 *   University    of   California,   Berkeley,   and   from   Bell	*
 *   Laboratories.  Use, duplication, or disclosure is  subject  to	*
 *   restrictions  under  license  agreements  with  University  of	*
 *   California and with AT&T.						*
 *									*
 *   The information in this software is subject to change  without	*
 *   notice  and should not be construed as a commitment by Digital	*
 *   Equipment Corporation.						*
 *									*
 *   Digital assumes no responsibility for the use  or  reliability	*
 *   of its software on equipment which is not supplied by Digital.	*
 *									*
 ************************************************************************/

/************************************************************************
 *	Modification History
 *      --------------------
 *
 *	9-Jan-89		Tim N
 *		Added usage error message for bad options.
 *		Added check for null pointer on command line when getting
 *		the -f switch.  Added sccs keywords, header and this comment
 *		block.  This module contained the ident:
 *				"@(#)main.c	4.2 8/11/83";
 ************************************************************************/

#include "stdio.h"
#include "ctype.h"
#include "awk.def"
#include "awk.h"
#define TOLOWER(c)	(isupper(c) ? tolower(c) : c) /* ugh!!! */

int	dbg	= 0;
int	svflg	= 0;
int	rstflg	= 0;
int	svargc;
char	**svargv, **xargv;
extern FILE	*yyin;	/* lex input file */
char	*lexprog;	/* points to program argument if it exists */
extern	errorflag;	/* non-zero if any syntax errors; set by yyerror */

int filefd, symnum, ansfd;
char *filelist;
extern int maxsym, errno;
main(argc, argv) int argc; char *argv[]; {
	if (argc == 1)
		error(FATAL, "Usage: awk [-f source | 'cmds'] [files]");
	if (strcmp(argv[0], "a.out"))
		logit(argc, argv);
	syminit();
	while (argc > 1) {
		argc--;
		argv++;
		/* this nonsense is because gcos argument handling */
		/* folds -F into -f.  accordingly, one checks the next
		/* character after f to see if it's -f file or -Fx.
		*/
		if (argv[0][0] == '-' && TOLOWER(argv[0][1]) == 'f' && argv[0][2] == '\0') {
			/* check for file name argument - Tim N */
			if (!argv[1])
			    error(FATAL, "Usage: awk [-f source | 'cmds'] [files]");
			yyin = fopen(argv[1], "r");
			if (yyin == NULL)
				error(FATAL, "can't open %s", argv[1]);
			argc--;
			argv++;
			break;
		} else if (argv[0][0] == '-' && TOLOWER(argv[0][1]) == 'f') {	/* set field sep */
			if (argv[0][2] == 't')	/* special case for tab */
				**FS = '\t';
			else
				**FS = argv[0][2];
			continue;
		} else if (argv[0][0] != '-') {
			dprintf("cmds=|%s|\n", argv[0], NULL, NULL);
			yyin = NULL;
			lexprog = argv[0];
			argv[0] = argv[-1];	/* need this space */
			break;
		} else if (strcmp("-d", argv[0])==0) {
			dbg = 1;
		}
		else if(strcmp("-S", argv[0]) == 0) {
			svflg = 1;
		}
		else if(strncmp("-R", argv[0], 2) == 0) {
			if(thaw(argv[0] + 2) == 0)
				rstflg = 1;
			else {
				fprintf(stderr, "not restored\n");
				exit(1);
			}
		}
		else
		    error(FATAL, "Usage: awk [-f source | 'cmds'] [files]");
	}
	if (argc <= 1) {
		argv[0][0] = '-';
		argv[0][1] = '\0';
		argc++;
		argv--;
	}
	svargc = --argc;
	svargv = ++argv;
	dprintf("svargc=%d svargv[0]=%s\n", svargc, svargv[0], NULL);
	*FILENAME = *svargv;	/* initial file name */
	if(rstflg == 0)
		yyparse();
	dprintf("errorflag=%d\n", errorflag, NULL, NULL);
	if (errorflag)
		exit(errorflag);
	if(svflg) {
		svflg = 0;
		if(freeze("awk.out") != 0)
			fprintf(stderr, "not saved\n");
		exit(0);
	}
	run();
	exit(errorflag);
}

logit(n, s) char *s[];
{	int i, tvec[2];
	FILE *f, *g;
	char buf[512];
	if ((f=fopen("/crp/pjw/awkhist/awkhist", "a"))==NULL)
		return;
	time(tvec);
	fprintf(f, "%-8s %s", getlogin(), ctime(tvec));
	for (i=0; i<n; i++)
		fprintf(f, "'%s'", s[i]);
	putc('\n', f);
	if (strcmp(s[1], "-f")) {
		fclose(f);
		return;
	}
	if ((g=fopen(s[2], "r"))==NULL) {
		fclose(f);
		return;
	}
	while ((i=fread(buf, 1, 512, g))>0)
		fwrite(buf, 1, i, f);
	fclose(f);
	fclose(g);
}

yywrap()
{
	return(1);
}