Import The One True Awk

https://github.com/onetrueawk/awk

third_party/awk/parse.c

@@ -0,0 +1,276 @@
+/****************************************************************
+Copyright (C) Lucent Technologies 1997
+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 Lucent Technologies or any of
+its entities not be used in advertising or publicity pertaining
+to distribution of the software without specific, written prior
+permission.
+
+LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
+IN NO EVENT SHALL LUCENT 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 <stdlib.h>
+#include "awk.h"
+#include "awkgram.tab.h"
+
+Node *nodealloc(int n)
+{
+	Node *x;
+
+	x = (Node *) malloc(sizeof(*x) + (n-1) * sizeof(x));
+	if (x == NULL)
+		FATAL("out of space in nodealloc");
+	x->nnext = NULL;
+	x->lineno = lineno;
+	return(x);
+}
+
+Node *exptostat(Node *a)
+{
+	a->ntype = NSTAT;
+	return(a);
+}
+
+Node *node1(int a, Node *b)
+{
+	Node *x;
+
+	x = nodealloc(1);
+	x->nobj = a;
+	x->narg[0]=b;
+	return(x);
+}
+
+Node *node2(int a, Node *b, Node *c)
+{
+	Node *x;
+
+	x = nodealloc(2);
+	x->nobj = a;
+	x->narg[0] = b;
+	x->narg[1] = c;
+	return(x);
+}
+
+Node *node3(int a, Node *b, Node *c, Node *d)
+{
+	Node *x;
+
+	x = nodealloc(3);
+	x->nobj = a;
+	x->narg[0] = b;
+	x->narg[1] = c;
+	x->narg[2] = d;
+	return(x);
+}
+
+Node *node4(int a, Node *b, Node *c, Node *d, Node *e)
+{
+	Node *x;
+
+	x = nodealloc(4);
+	x->nobj = a;
+	x->narg[0] = b;
+	x->narg[1] = c;
+	x->narg[2] = d;
+	x->narg[3] = e;
+	return(x);
+}
+
+Node *stat1(int a, Node *b)
+{
+	Node *x;
+
+	x = node1(a,b);
+	x->ntype = NSTAT;
+	return(x);
+}
+
+Node *stat2(int a, Node *b, Node *c)
+{
+	Node *x;
+
+	x = node2(a,b,c);
+	x->ntype = NSTAT;
+	return(x);
+}
+
+Node *stat3(int a, Node *b, Node *c, Node *d)
+{
+	Node *x;
+
+	x = node3(a,b,c,d);
+	x->ntype = NSTAT;
+	return(x);
+}
+
+Node *stat4(int a, Node *b, Node *c, Node *d, Node *e)
+{
+	Node *x;
+
+	x = node4(a,b,c,d,e);
+	x->ntype = NSTAT;
+	return(x);
+}
+
+Node *op1(int a, Node *b)
+{
+	Node *x;
+
+	x = node1(a,b);
+	x->ntype = NEXPR;
+	return(x);
+}
+
+Node *op2(int a, Node *b, Node *c)
+{
+	Node *x;
+
+	x = node2(a,b,c);
+	x->ntype = NEXPR;
+	return(x);
+}
+
+Node *op3(int a, Node *b, Node *c, Node *d)
+{
+	Node *x;
+
+	x = node3(a,b,c,d);
+	x->ntype = NEXPR;
+	return(x);
+}
+
+Node *op4(int a, Node *b, Node *c, Node *d, Node *e)
+{
+	Node *x;
+
+	x = node4(a,b,c,d,e);
+	x->ntype = NEXPR;
+	return(x);
+}
+
+Node *celltonode(Cell *a, int b)
+{
+	Node *x;
+
+	a->ctype = OCELL;
+	a->csub = b;
+	x = node1(0, (Node *) a);
+	x->ntype = NVALUE;
+	return(x);
+}
+
+Node *rectonode(void)	/* make $0 into a Node */
+{
+	extern Cell *literal0;
+	return op1(INDIRECT, celltonode(literal0, CUNK));
+}
+
+Node *makearr(Node *p)
+{
+	Cell *cp;
+
+	if (isvalue(p)) {
+		cp = (Cell *) (p->narg[0]);
+		if (isfcn(cp))
+			SYNTAX( "%s is a function, not an array", cp->nval );
+		else if (!isarr(cp)) {
+			xfree(cp->sval);
+			cp->sval = (char *) makesymtab(NSYMTAB);
+			cp->tval = ARR;
+		}
+	}
+	return p;
+}
+
+#define PA2NUM	50	/* max number of pat,pat patterns allowed */
+int	paircnt;		/* number of them in use */
+int	pairstack[PA2NUM];	/* state of each pat,pat */
+
+Node *pa2stat(Node *a, Node *b, Node *c)	/* pat, pat {...} */
+{
+	Node *x;
+
+	x = node4(PASTAT2, a, b, c, itonp(paircnt));
+	if (paircnt++ >= PA2NUM)
+		SYNTAX( "limited to %d pat,pat statements", PA2NUM );
+	x->ntype = NSTAT;
+	return(x);
+}
+
+Node *linkum(Node *a, Node *b)
+{
+	Node *c;
+
+	if (errorflag)	/* don't link things that are wrong */
+		return a;
+	if (a == NULL)
+		return(b);
+	else if (b == NULL)
+		return(a);
+	for (c = a; c->nnext != NULL; c = c->nnext)
+		;
+	c->nnext = b;
+	return(a);
+}
+
+void defn(Cell *v, Node *vl, Node *st)	/* turn on FCN bit in definition, */
+{					/*   body of function, arglist */
+	Node *p;
+	int n;
+
+	if (isarr(v)) {
+		SYNTAX( "`%s' is an array name and a function name", v->nval );
+		return;
+	}
+	if (isarg(v->nval) != -1) {
+		SYNTAX( "`%s' is both function name and argument name", v->nval );
+		return;
+	}
+
+	v->tval = FCN;
+	v->sval = (char *) st;
+	n = 0;	/* count arguments */
+	for (p = vl; p; p = p->nnext)
+		n++;
+	v->fval = n;
+	DPRINTF("defining func %s (%d args)\n", v->nval, n);
+}
+
+int isarg(const char *s)		/* is s in argument list for current function? */
+{			/* return -1 if not, otherwise arg # */
+	extern Node *arglist;
+	Node *p = arglist;
+	int n;
+
+	for (n = 0; p != NULL; p = p->nnext, n++)
+		if (strcmp(((Cell *)(p->narg[0]))->nval, s) == 0)
+			return n;
+	return -1;
+}
+
+int ptoi(void *p)	/* convert pointer to integer */
+{
+	return (int) (long) p;	/* swearing that p fits, of course */
+}
+
+Node *itonp(int i)	/* and vice versa */
+{
+	return (Node *) (long) i;
+}