lib.c

早期freebsd实现

/****************************************************************
Copyright (C) AT&T 1993
All Rights Reserved

Permission to use, copy, modify, and distribute this software and
its documentation for any purpose and without fee is hereby
granted, provided that the above copyright notice appear in all
copies and that both that the copyright notice and this
permission notice and warranty disclaimer appear in supporting
documentation, and that the name of AT&T or any of its entities
not be used in advertising or publicity pertaining to
distribution of the software without specific, written prior
permission.

AT&T DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
IN NO EVENT SHALL AT&T OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
THIS SOFTWARE.
****************************************************************/

#define DEBUG
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
#include <stdlib.h>
#include "awk.h"
#include "y.tab.h"

#define	getfval(p)	(((p)->tval & (ARR|FLD|REC|NUM)) == NUM ? (p)->fval : r_getfval(p))
#define	getsval(p)	(((p)->tval & (ARR|FLD|REC|STR)) == STR ? (p)->sval : r_getsval(p))

FILE	*infile	= NULL;
uchar	*file	= (uchar*) "";
int	recsize	= RECSIZE;
uchar	*recdata;
uchar	*record;
uchar	*fields;
Cell	*fldtab;

#define	MAXFLD	200
int	nfields	= MAXFLD;	/* can be set from commandline in main */

int	donefld;	/* 1 = implies rec broken into fields */
int	donerec;	/* 1 = record is valid (no flds have changed) */

int	maxfld	= 0;	/* last used field */
int	argno	= 1;	/* current input argument number */
extern	Awkfloat *ARGC;

void recinit(unsigned int n)
{
	static Cell dollar0 = {
	    OCELL, CFLD, (uchar*) "$0", /*recdata*/0, 0.0, REC|STR|DONTFREE };
	static Cell dollar1 = {
	    OCELL, CFLD, NULL, (uchar*) "", 0.0, FLD|STR|DONTFREE };
	int i;

	record = recdata = (uchar *) malloc(n);
	fields = (uchar *) malloc(n);
	fldtab = (Cell *) malloc(nfields * sizeof(Cell));
	if (recdata == NULL || fields == NULL || fldtab == NULL)
		ERROR "out of space for $0 and fields" FATAL;
	fldtab[0] = dollar0;
	fldtab[0].sval = recdata;
	for (i = 1; i < nfields; i++)
		fldtab[i] = dollar1;
}

void initgetrec(void)
{
	int i;
	uchar *p;

	for (i = 1; i < *ARGC; i++) {
		if (!isclvar(p = getargv(i))) {	/* find 1st real filename */
			setsval(lookup("FILENAME", symtab), getargv(i));
			return;
		}
		setclvar(p);	/* a commandline assignment before filename */
		argno++;
	}
	infile = stdin;		/* no filenames, so use stdin */
}

getrec(uchar *buf)	/* get next input record from whatever source */
{			/* note: tests whether buf == record */
	int c;
	static int firsttime = 1;

	if (firsttime) {
		firsttime = 0;
		initgetrec();
	}
	dprintf( ("RS=<%s>, FS=<%s>, ARGC=%g, FILENAME=%s\n",
		*RS, *FS, *ARGC, *FILENAME) );
	donefld = 0;
	donerec = 1;
	buf[0] = 0;
	while (argno < *ARGC || infile == stdin) {
		dprintf( ("argno=%d, file=|%s|\n", argno, file) );
		if (infile == NULL) {	/* have to open a new file */
			file = getargv(argno);
			if (*file == '\0') {	/* it's been zapped */
				argno++;
				continue;
			}
			if (isclvar(file)) {	/* a var=value arg */
				setclvar(file);
				argno++;
				continue;
			}
			*FILENAME = file;
			dprintf( ("opening file %s\n", file) );
			if (*file == '-' && *(file+1) == '\0')
				infile = stdin;
			else if ((infile = fopen((char *)file, "r")) == NULL)
				ERROR "can't open file %s", file FATAL;
			setfval(fnrloc, 0.0);
		}
		c = readrec(buf, recsize, infile);
		if (c != 0 || buf[0] != '\0') {	/* normal record */
			if (buf == record) {
				if (!(recloc->tval & DONTFREE))
					xfree(recloc->sval);
				recloc->sval = record;
				recloc->tval = REC | STR | DONTFREE;
				if (is_a_number(recloc->sval)) {
					recloc->fval = atof(recloc->sval);
					recloc->tval |= NUM;
				}
			}
			setfval(nrloc, nrloc->fval+1);
			setfval(fnrloc, fnrloc->fval+1);
			return 1;
		}
		/* EOF arrived on this file; set up next */
		if (infile != stdin)
			fclose(infile);
		infile = NULL;
		argno++;
	}
	return 0;	/* true end of file */
}

readrec(uchar *buf, int bufsize, FILE *inf)	/* read one record into buf */
{
	register int sep, c;
	register uchar *rr;
	register int nrr;

	if ((sep = **RS) == 0) {
		sep = '\n';
		while ((c=getc(inf)) == '\n' && c != EOF)	/* skip leading \n's */
			;
		if (c != EOF)
			ungetc(c, inf);
	}
	for (rr = buf, nrr = bufsize; ; ) {
		for (; (c=getc(inf)) != sep && c != EOF; *rr++ = c)
			if (--nrr < 0)
				ERROR "input record `%.30s...' too long; try -mr n", buf FATAL;
		if (**RS == sep || c == EOF)
			break;
		if ((c = getc(inf)) == '\n' || c == EOF) /* 2 in a row */
			break;
		*rr++ = '\n';
		*rr++ = c;
	}
	if (rr > buf + bufsize)
		ERROR "input record `%.30s...' too long; try -mr n", buf FATAL;
	*rr = 0;
	dprintf( ("readrec saw <%s>, returns %d\n", buf, c == EOF && rr == buf ? 0 : 1) );
	return c == EOF && rr == buf ? 0 : 1;
}

uchar *getargv(int n)	/* get ARGV[n] */
{
	Cell *x;
	uchar *s, temp[10];
	extern Array *ARGVtab;

	sprintf((char *)temp, "%d", n);
	x = setsymtab(temp, "", 0.0, STR, ARGVtab);
	s = getsval(x);
	dprintf( ("getargv(%d) returns |%s|\n", n, s) );
	return s;
}

void setclvar(uchar *s)	/* set var=value from s */
{
	uchar *p;
	Cell *q;

	for (p=s; *p != '='; p++)
		;
	*p++ = 0;
	p = qstring(p, '\0');
	q = setsymtab(s, p, 0.0, STR, symtab);
	setsval(q, p);
	if (is_a_number(q->sval)) {
		q->fval = atof(q->sval);
		q->tval |= NUM;
	}
	dprintf( ("command line set %s to |%s|\n", s, p) );
}


void fldbld(void)	/* create fields from current record */
{
	register uchar *r, *fr, sep;
	Cell *p;
	int i;

	if (donefld)
		return;
	if (!(recloc->tval & STR))
		getsval(recloc);
	r = recloc->sval;
	fr = fields;
	i = 0;	/* number of fields accumulated here */
	if (strlen(*FS) > 1) {	/* it's a regular expression */
		i = refldbld(r, *FS);
	} else if ((sep = **FS) == ' ') {	/* default whitespace */
		for (i = 0; ; ) {
			while (*r == ' ' || *r == '\t' || *r == '\n')
				r++;
			if (*r == 0)
				break;
			i++;
			if (i >= nfields)
				break;
			if (!(fldtab[i].tval & DONTFREE))
				xfree(fldtab[i].sval);
			fldtab[i].sval = fr;
			fldtab[i].tval = FLD | STR | DONTFREE;
			do
				*fr++ = *r++;
			while (*r != ' ' && *r != '\t' && *r != '\n' && *r != '\0');
			*fr++ = 0;
		}
		*fr = 0;
	} else if (*r != 0) {	/* if 0, it's a null field */
		for (;;) {
			i++;
			if (i >= nfields)
				break;
			if (!(fldtab[i].tval & DONTFREE))
				xfree(fldtab[i].sval);
			fldtab[i].sval = fr;
			fldtab[i].tval = FLD | STR | DONTFREE;
			while (*r != sep && *r != '\n' && *r != '\0')	/* \n is always a separator */
				*fr++ = *r++;
			*fr++ = 0;
			if (*r++ == 0)
				break;
		}
		*fr = 0;
	}
	if (i >= nfields)
		ERROR "record `%.30s...' has too many fields; try -mf n", record FATAL;
	/* clean out junk from previous record */
	cleanfld(i, maxfld);
	maxfld = i;
	donefld = 1;
	for (p = fldtab+1; p <= fldtab+maxfld; p++) {
		if(is_a_number(p->sval)) {
			p->fval = atof(p->sval);
			p->tval |= NUM;
		}
	}
	setfval(nfloc, (Awkfloat) maxfld);
	if (dbg)
		for (p = fldtab; p <= fldtab+maxfld; p++)
			printf("field %d: |%s|\n", p-fldtab, p->sval);
}

void cleanfld(int n1, int n2)	/* clean out fields n1..n2 inclusive */
{
	static uchar *nullstat = (uchar *) "";
	register Cell *p, *q;

	for (p = &fldtab[n2], q = &fldtab[n1]; p > q; p--) {
		if (!(p->tval & DONTFREE))
			xfree(p->sval);
		p->tval = FLD | STR | DONTFREE;
		p->sval = nullstat;
	}
}

void newfld(int n)	/* add field n (after end) */
{
	if (n >= nfields)
		ERROR "creating too many fields (%d); try -mf n", n, record FATAL;
	cleanfld(maxfld, n);
	maxfld = n;
	setfval(nfloc, (Awkfloat) n);
}

refldbld(uchar *rec, uchar *fs)	/* build fields from reg expr in FS */
{
	uchar *fr;
	int i, tempstat;
	fa *pfa;

	fr = fields;
	*fr = '\0';
	if (*rec == '\0')
		return 0;
	pfa = makedfa(fs, 1);
	dprintf( ("into refldbld, rec = <%s>, pat = <%s>\n", rec, fs) );
	tempstat = pfa->initstat;
	for (i = 1; i < nfields; i++) {
		if (!(fldtab[i].tval & DONTFREE))
			xfree(fldtab[i].sval);
		fldtab[i].tval = FLD | STR | DONTFREE;
		fldtab[i].sval = fr;
		dprintf( ("refldbld: i=%d\n", i) );
		if (nematch(pfa, rec)) {
			pfa->initstat = 2;	/* horrible coupling */
			dprintf( ("match %s (%d chars)\n", patbeg, patlen) );
			strncpy(fr, rec, patbeg-rec);
			fr += patbeg - rec + 1;
			*(fr-1) = '\0';
			rec = patbeg + patlen;
		} else {
			dprintf( ("no match %s\n", rec) );
			strcpy(fr, rec);
			pfa->initstat = tempstat;
			break;
		}
	}
	return i;		
}

void recbld(void)	/* create $0 from $1..$NF if necessary */
{
	register int i;
	register uchar *r, *p;
	static uchar *rec = 0;

	if (donerec == 1)
		return;
	if (rec == 0) {
		rec = (uchar *) malloc(recsize);
		if (rec == 0)
			ERROR "out of space building $0, record size %d", recsize FATAL;
	}
	r = rec;
	for (i = 1; i <= *NF; i++) {
		p = getsval(&fldtab[i]);
		while (r < rec+recsize-1 && (*r = *p++))
			r++;
		if (i < *NF)
			for (p = *OFS; r < rec+recsize-1 && (*r = *p++); )
				r++;
	}
	if (r > rec + recsize - 1)
		ERROR "built giant record `%.30s...'; try -mr n", record FATAL;
	*r = '\0';
	dprintf( ("in recbld FS=%o, recloc=%o\n", **FS, recloc) );
	recloc->tval = REC | STR | DONTFREE;
	recloc->sval = record = rec;
	dprintf( ("in recbld FS=%o, recloc=%o\n", **FS, recloc) );
	dprintf( ("recbld = |%s|\n", record) );
	donerec = 1;
}

Cell *fieldadr(int n)
{
	if (n < 0 || n >= nfields)
		ERROR "trying to access field %d; try -mf n", n FATAL;
	return(&fldtab[n]);
}

int	errorflag	= 0;
char	errbuf[200];

void yyerror(uchar *s)
{
	extern uchar *cmdname, *curfname;
	static int been_here = 0;

	if (been_here++ > 2)
		return;
	fprintf(stderr, "%s: %s", cmdname, s);
	fprintf(stderr, " at source line %d", lineno);
	if (curfname != NULL)
		fprintf(stderr, " in function %s", curfname);
	fprintf(stderr, "\n");
	errorflag = 2;
	eprint();
}

void fpecatch(int n)
{
	ERROR "floating point exception %d", n FATAL;
}

extern int bracecnt, brackcnt, parencnt;

void bracecheck(void)
{
	int c;
	static int beenhere = 0;

	if (beenhere++)
		return;
	while ((c = lex_input()) != EOF && c != '\0')
		bclass(c);
	bcheck2(bracecnt, '{', '}');
	bcheck2(brackcnt, '[', ']');
	bcheck2(parencnt, '(', ')');
}

void bcheck2(int n, int c1, int c2)
{
	if (n == 1)
		fprintf(stderr, "\tmissing %c\n", c2);
	else if (n > 1)
		fprintf(stderr, "\t%d missing %c's\n", n, c2);
	else if (n == -1)
		fprintf(stderr, "\textra %c\n", c2);
	else if (n < -1)
		fprintf(stderr, "\t%d extra %c's\n", -n, c2);
}

void error(int f, char *s)
{
	extern Node *curnode;
	extern uchar *cmdname;

	fflush(stdout);
	fprintf(stderr, "%s: ", cmdname);
	fprintf(stderr, "%s", s);
	fprintf(stderr, "\n");
	if (compile_time != 2 && NR && *NR > 0) {
		fprintf(stderr, " input record number %g", *FNR);
		if (strcmp(*FILENAME, "-") != 0)
			fprintf(stderr, ", file %s", *FILENAME);
		fprintf(stderr, "\n");
	}
	if (compile_time != 2 && curnode)
		fprintf(stderr, " source line number %d\n", curnode->lineno);
	else if (compile_time != 2 && lineno)
		fprintf(stderr, " source line number %d\n", lineno);
	eprint();
	if (f) {
		if (dbg > 1)		/* core dump if serious debugging on */
			abort();
		exit(2);
	}
}

void eprint(void)	/* try to print context around error */
{
#if 0
	uchar *p, *q;
	int c;
	static int been_here = 0;
	extern uchar ebuf[], *ep;

	if (compile_time == 2 || compile_time == 0 || been_here++ > 0)
		return;
	p = ep - 1;
	if (p > ebuf && *p == '\n')
		p--;
	for ( ; p > ebuf && *p != '\n' && *p != '\0'; p--)
		;
	while (*p == '\n')
		p++;
	fprintf(stderr, " context is\n\t");
	for (q=ep-1; q>=p && *q!=' ' && *q!='\t' && *q!='\n'; q--)
		;
	for ( ; p < q; p++)
		if (*p)
			putc(*p, stderr);
	fprintf(stderr, " >>> ");
	for ( ; p < ep; p++)
		if (*p)
			putc(*p, stderr);
	fprintf(stderr, " <<< ");
	if (*ep)
		while ((c = input()) != '\n' && c != '\0' && c != EOF) {
			putc(c, stderr);
			bclass(c);
		}
	putc('\n', stderr);
	ep = ebuf;
#endif
}

void bclass(int c)
{
	switch (c) {
	case '{': bracecnt++; break;
	case '}': bracecnt--; break;
	case '[': brackcnt++; break;
	case ']': brackcnt--; break;
	case '(': parencnt++; break;
	case ')': parencnt--; break;
	}
}

double errcheck(double x, uchar *s)
{
	extern int errno;

	if (errno == EDOM) {
		errno = 0;
		ERROR "%s argument out of domain", s WARNING;
		x = 1;
	} else if (errno == ERANGE) {
		errno = 0;
		ERROR "%s result out of range", s WARNING;
		x = 1;
	}
	return x;
}

isclvar(uchar *s)	/* is s of form var=something ? */
{
	uchar *os = s;

	if (!isalpha(*s) && *s != '_')
		return 0;
	for ( ; *s; s++)
		if (!(isalnum(*s) || *s == '_'))
			break;
	return *s == '=' && s > os && *(s+1) != '=';
}

#define	MAXEXPON	38	/* maximum exponent for fp number. should be IEEE */

is_a_number(uchar *s)	/* probably should be done by a library function */
{
	register int d1, d2;
	int point;
	uchar *es;

	d1 = d2 = point = 0;
	while (*s == ' ' || *s == '\t' || *s == '\n')
		s++;
	if (*s == '\0')
		return(0);	/* empty stuff isn't number */
	if (*s == '+' || *s == '-')
		s++;
	if (!isdigit(*s) && *s != '.')
		return(0);
	if (isdigit(*s)) {
		do {
			d1++;
			s++;
		} while (isdigit(*s));
	}
	if (*s == '.') {
		point++;
		s++;
	}
	if (isdigit(*s)) {
		d2++;
		do {
			s++;
		} while (isdigit(*s));
	}
	if (!(d1 || point && d2))
		return(0);
	if (*s == 'e' || *s == 'E') {
		s++;
		if (*s == '+' || *s == '-')
			s++;
		if (!isdigit(*s))
			return(0);
		es = s;
		do {
			s++;
		} while (isdigit(*s));
		if (s - es > 2)
			return(0);
		else if (s - es == 2 && (int)(10 * (*es-'0') + *(es+1)-'0') >= MAXEXPON)
			return(0);
	}
	while (*s == ' ' || *s == '\t' || *s == '\n')
		s++;
	if (*s == '\0')
		return(1);
	else
		return(0);
}