pcctsast.cpp

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	SList *list = new SList;
	PCCTS_AST *p;

	for (p=this; p!=NULL; p=p->right())
	{
		list->add(p);
	}
	return list;
}
#endif

void PCCTS_AST::
tfree()
{
	PCCTS_AST *t = this;
    if ( t->down()!=NULL ) t->down()->tfree();
    if ( t->right()!=NULL ) t->right()->tfree();
    delete t;
}

int PCCTS_AST::
nsiblings()
{
	PCCTS_AST *t = this;
	int n=0;

	while ( t!=NULL )
	{
		n++;
		t = t->right();
	}
	return n;
}

PCCTS_AST *PCCTS_AST::
sibling_index(int i)
{
	PCCTS_AST *t = this;
	int j=1;
	require(i>0, "sibling_index: i<=0");

	while ( t!=NULL )
	{
		if ( j==i ) return t;
		j++;
		t = t->right();
	}
	return NULL;
}

/* Assume this is a root node of a tree--
 * duplicate that node and what's below; ignore siblings of root node.
 */

// MR9 23-Sep-97 RJV
// MR9
// MR9 RJV: Original version only duplicated the node and down elements.
// MR9      Made copies of the pointers to sibling.
// MR9      Changed call "down()->deepCopy()" to "down()->deepCopyBushy()"
// MR9

PCCTS_AST *PCCTS_AST::
deepCopy()
{
	PCCTS_AST *u = this->shallowCopy();
	if ( down()!=NULL ) u->setDown(down()->deepCopyBushy());
    u->setRight(NULL);
	return u;
}

/* Copy all nodes including siblings of root. */
PCCTS_AST *PCCTS_AST::
deepCopyBushy()
{
	PCCTS_AST *u = this->shallowCopy();
	/* copy the rest of the tree */
	if ( down()!=NULL ) u->setDown(down()->deepCopyBushy());
	if ( right()!=NULL ) u->setRight(right()->deepCopyBushy());
	return u;
}

void PCCTS_AST::
scanast_free(ScanAST *t)
{
    if ( t == NULL ) return;
    scanast_free( t->down() );
    scanast_free( t->right() );
    free( (char *) t );							// MR1
}

/*
 * scan
 *
 * This function is like scanf(): it attempts to match a template
 * against an input tree.  A variable number of tree pointers
 * may be set according to the '%i' labels in the template string.
 * For example:
 *
 *   t->ast_scan("#( 6 #(5 %1:4 %2:3) #(1 %3:3 %4:3) )",
 *            &w, &x, &y, &z);
 *
 * Naturally, you'd want this converted from
 *
 *	 t->ast_scan("#( RangeOp #(Minus %1:IConst %2:Var) #(Plus %3:Var %4Var) )",
 *			  &w, &x, &y, &z);
 *
 * by SORCERER.
 *
 * This function call must be done withing a SORCERER file because SORCERER
 * must convert the token references to the associated token number.
 *
 * This functions parses the template and creates trees which are then
 * matched against the input tree.  The labels are set as they are
 * encountered; hence, partial matches may leave some pointers set
 * and some NULL.  This routines initializes all argument pointers to NULL
 * at the beginning.
 *
 * This function returns the number of labels matched.
 */
int PCCTS_AST::
ast_scan(char *templ, ...)
{
	va_list ap;
	ScanAST *tmpl;
	int n, i, found=0;
	PCCTS_AST ***label_ptrs=NULL;

	va_start(ap, templ);

	/* make a ScanAST tree out of the template */
	tmpl = stringparser_parse_scanast(templ, &n);

	/* make an array out of the labels */
	if ( n>0 )
	{
		label_ptrs = (PCCTS_AST ***) calloc(n, sizeof(PCCTS_AST **));
		require(label_ptrs!=NULL, "scan: out of memory");
		for (i=1; i<=n; i++)
		{
			label_ptrs[i-1] = va_arg(ap, PCCTS_AST **);
			*(label_ptrs[i-1]) = NULL;
		}
	}

	/* match the input tree against the template */
	scanmatch(tmpl, label_ptrs, &found);

	scanast_free(tmpl);
	free( (char *) label_ptrs);					// MR1

	return found;
}

ScanAST *PCCTS_AST::
new_scanast(int tok)
{
    ScanAST *p = (ScanAST *) calloc(1, sizeof(ScanAST));
//
//  7-Apr-97 133MR1
//
    if ( p == NULL ) {							// MR1
	        fprintf(stderr, "out of mem\n");			// MR1
        	exit(PCCTS_EXIT_FAILURE);				// MR1
    };									// MR1
	p->_token = tok;
	return p;
}

ScanAST *PCCTS_AST::
stringparser_parse_scanast(char *templ, int *num_labels)
{
	StringLexer lex;
	StringParser parser;
	ScanAST *t;

	stringlexer_init(&lex, templ);
	stringparser_init(&parser, &lex);
	t = stringparser_parse_tree(&parser);
	*num_labels = parser.num_labels;
	return t;
}

void PCCTS_AST::
stringparser_match(StringParser *parser, int token)
{
	if ( parser->token != token ) panic("bad tree in scan()");
}

/*
 * Match a tree of the form:
 *		(root child1 child2 ... childn)
 * or,
 *		node
 *
 * where the elements are integers or labeled integers.
 */
ScanAST *PCCTS_AST::
stringparser_parse_tree(StringParser *parser)
{
	ScanAST *t=NULL, *root, *child, *last;

	if ( parser->token != __POUND )
	{
		return stringparser_parse_element(parser);
	}
	stringparser_match(parser,__POUND);
	parser->token = stringscan_gettok(parser->lexer);
	stringparser_match(parser,__LPAREN);
	parser->token = stringscan_gettok(parser->lexer);
	root = stringparser_parse_element(parser);
	while ( parser->token != __RPAREN )
	{
		child = stringparser_parse_element(parser);
		if ( t==NULL ) { t = child; last = t; }
		else { last->_right = child; last = child; }
	}
	stringparser_match(parser,__RPAREN);
	parser->token = stringscan_gettok(parser->lexer);
	root->_down = t;
	return root;
}

ScanAST *PCCTS_AST::
stringparser_parse_element(StringParser *parser)
{
	static char ebuf[100];
	int label = 0;

	if ( parser->token == __POUND )
	{
		return stringparser_parse_tree(parser);
	}
	if ( parser->token == __PERCENT )
	{
		parser->token = stringscan_gettok(parser->lexer);
		stringparser_match(parser,__INT);
		label = atoi(parser->lexer->text);
		parser->num_labels++;
		if ( label==0 ) panic("%%0 is an invalid label");
		parser->token = stringscan_gettok(parser->lexer);
		stringparser_match(parser,__COLON);
		parser->token = stringscan_gettok(parser->lexer);
		/* can label tokens and wildcards */
		if ( parser->token != __INT && parser->token != __PERIOD )
			panic("can only label tokens");
	}
	if ( parser->token == __INT )
	{
		ScanAST *p = new_scanast(atoi(parser->lexer->text));
		parser->token = stringscan_gettok(parser->lexer);
		p->label_num = label;
		return p;
	}
	if ( parser->token == __PERIOD )
	{
		ScanAST *p = new_scanast(0);	/* token of 0 is wildcard */
		parser->token = stringscan_gettok(parser->lexer);
		p->label_num = label;
		return p;
	}
	sprintf(ebuf, "mismatch token in scan(): %s", scan_token_str(parser->token));
	panic(ebuf);
	return NULL;
}

void PCCTS_AST::
stringparser_init(StringParser *parser, StringLexer *input)
{
	parser->lexer = input;
	parser->token = stringscan_gettok(parser->lexer);
	parser->num_labels = 0;
}

void PCCTS_AST::
stringlexer_init(StringLexer *scanner, char *input)
{
	scanner->text[0]='\0';
	scanner->input = input;
	scanner->p = input;
	stringscan_advance(scanner);
}

void PCCTS_AST::
stringscan_advance(StringLexer *scanner)
{
	if ( *(scanner->p) == '\0' ) scanner->c = __StringScanEOF;
	scanner->c = *(scanner->p)++;
}

int PCCTS_AST::
stringscan_gettok(StringLexer *scanner)
{
	char *index = &scanner->text[0];
	static char ebuf[100];

	while ( isspace(scanner->c) ) { stringscan_advance(scanner); }
	if ( isdigit(scanner->c) )
	{
		int tok = __INT;
		while ( isdigit(scanner->c) ) {
			*index++ = scanner->c;
			stringscan_advance(scanner);
		}
		*index = '\0';
		return tok;
	}
	switch ( scanner->c )
	{
		case '#' : stringscan_advance(scanner); return __POUND;
		case '(' : stringscan_advance(scanner); return __LPAREN;
		case ')' : stringscan_advance(scanner); return __RPAREN;
		case '%' : stringscan_advance(scanner); return __PERCENT;
		case ':' : stringscan_advance(scanner); return __COLON;
		case '.' : stringscan_advance(scanner); return __PERIOD;
		case '\0' : return __StringScanEOF;
		case __StringScanEOF : return __StringScanEOF;
		default  :
			sprintf(ebuf, "invalid char in scan: '%c'", scanner->c);
			panic(ebuf);
	}
	return __StringScanEOF;	// never reached
}

char *PCCTS_AST::
scan_token_str(int t)
{
	if ( VALID_SCAN_TOKEN(t) ) return scan_token_tbl[t];
	else if ( t==__StringScanEOF ) return "<end-of-string>";
	else return "<invalid-token>";
}