path: root/dtc-lexer.l

/*
 * (C) Copyright David Gibson <dwg@au1.ibm.com>, IBM Corporation.  2005.
 *
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 *                                                                   USA
 */

%option noyywrap nounput yylineno

%x INCLUDE
%x BYTESTRING
%x PROPNODENAME

PROPCHAR	[a-zA-Z0-9,._+*#?-]
UNITCHAR	[0-9a-f,]
WS		[[:space:]]

REFCHAR		({PROPCHAR}|{UNITCHAR}|[/@])

%{
#include "dtc.h"
#include "srcpos.h"
#include "dtc-parser.tab.h"


/*#define LEXDEBUG	1*/

#ifdef LEXDEBUG
#define DPRINT(fmt, ...)	fprintf(stderr, fmt, ##__VA_ARGS__)
#else
#define DPRINT(fmt, ...)	do { } while (0)
#endif



%}

%%

<*>"/include/"		BEGIN(INCLUDE);

<INCLUDE>\"[^"\n]*\"	{
			yytext[strlen(yytext) - 1] = 0;
			if (!push_input_file(yytext + 1)) {
				/* Some unrecoverable error.*/
				exit(1);
			}
			BEGIN(INITIAL);
		}


<*><<EOF>>		{
			if (!pop_input_file()) {
				yyterminate();
			}
		}

<*>\"([^\\"]|\\.)*\"	{
			yylloc.filenum = srcpos_filenum;
			yylloc.first_line = yylineno;
			DPRINT("String: %s\n", yytext);
			yylval.data = data_copy_escape_string(yytext+1,
					yyleng-2);
			yylloc.first_line = yylineno;
			return DT_STRING;
		}

<*>"/memreserve/"	{
			yylloc.filenum = srcpos_filenum;
			yylloc.first_line = yylineno;
			DPRINT("Keyword: /memreserve/\n");
			BEGIN(INITIAL);
			return DT_MEMRESERVE;
		}

<*>[a-zA-Z_][a-zA-Z0-9_]*:	{
			yylloc.filenum = srcpos_filenum;
			yylloc.first_line = yylineno;
			DPRINT("Label: %s\n", yytext);
			yylval.labelref = strdup(yytext);
			yylval.labelref[yyleng-1] = '\0';
			return DT_LABEL;
		}

[bodh]# {
			yylloc.filenum = srcpos_filenum;
			yylloc.first_line = yylineno;
			if (*yytext == 'b')
				yylval.cbase = 2;
			else if (*yytext == 'o')
				yylval.cbase = 8;
			else if (*yytext == 'd')
				yylval.cbase = 10;
			else
				yylval.cbase = 16;
			DPRINT("Base: %d\n", yylval.cbase);
			return DT_BASE;
		}

[0-9a-fA-F]+	{
			yylloc.filenum = srcpos_filenum;
			yylloc.first_line = yylineno;
			yylval.literal = strdup(yytext);
			DPRINT("Literal: '%s'\n", yylval.literal);
			return DT_LITERAL;
		}

\&{REFCHAR}*	{
			yylloc.filenum = srcpos_filenum;
			yylloc.first_line = yylineno;
			DPRINT("Ref: %s\n", yytext+1);
			yylval.labelref = strdup(yytext+1);
			return DT_REF;
		}

<BYTESTRING>[0-9a-fA-F]{2} {
			yylloc.filenum = srcpos_filenum;
			yylloc.first_line = yylineno;
			yylval.byte = strtol(yytext, NULL, 16);
			DPRINT("Byte: %02x\n", (int)yylval.byte);
			return DT_BYTE;
		}

<BYTESTRING>"]"	{
			yylloc.filenum = srcpos_filenum;
			yylloc.first_line = yylineno;
			DPRINT("/BYTESTRING\n");
			BEGIN(INITIAL);
			return ']';
		}

<PROPNODENAME>{PROPCHAR}+(@{UNITCHAR}+)? {
			yylloc.filenum = srcpos_filenum;
			yylloc.first_line = yylineno;
			DPRINT("PropNodeName: %s\n", yytext);
			yylval.propnodename = strdup(yytext);
			BEGIN(INITIAL);
			return DT_PROPNODENAME;
		}


<*>{WS}+	/* eat whitespace */

<*>"/*"([^*]|\*+[^*/])*\*+"/"	{
			yylloc.filenum = srcpos_filenum;
			yylloc.first_line = yylineno;
			DPRINT("Comment: %s\n", yytext);
			/* eat comments */
		}

<*>"//".*\n	/* eat line comments */

<*>.		{
			yylloc.filenum = srcpos_filenum;
			yylloc.first_line = yylineno;
			if (yytext[0] == '[') {
				DPRINT("<BYTESTRING>\n");
				BEGIN(BYTESTRING);
			}
			if ((yytext[0] == '{')
			    || (yytext[0] == ';')) {
				DPRINT("<PROPNODENAME>\n");
				BEGIN(PROPNODENAME);
			}
			DPRINT("Char: %c (\\x%02x)\n", yytext[0],
				(unsigned)yytext[0]);

			return yytext[0];
		}

%%


/*
 * Stack of nested include file contexts.
 */

struct incl_file {
	int filenum;
	FILE *file;
	YY_BUFFER_STATE yy_prev_buf;
	int yy_prev_lineno;
	struct incl_file *prev;
};

struct incl_file *incl_file_stack;


/*
 * Detect infinite include recursion.
 */
#define MAX_INCLUDE_DEPTH	(100)

static int incl_depth = 0;


int push_input_file(const char *filename)
{
	FILE *f;
	struct incl_file *incl_file;

	if (!filename) {
		yyerror("No include file name given.");
		return 0;
	}

	if (incl_depth++ >= MAX_INCLUDE_DEPTH) {
		yyerror("Includes nested too deeply");
		return 0;
	}

	f = dtc_open_file(filename);

	incl_file = malloc(sizeof(struct incl_file));
	if (!incl_file) {
		yyerror("Can not allocate include file space.");
		return 0;
	}

	/*
	 * Save current context.
	 */
	incl_file->yy_prev_buf = YY_CURRENT_BUFFER;
	incl_file->yy_prev_lineno = yylineno;
	incl_file->filenum = srcpos_filenum;
	incl_file->file = yyin;
	incl_file->prev = incl_file_stack;

	incl_file_stack = incl_file;

	/*
	 * Establish new context.
	 */
	srcpos_filenum = lookup_file_name(filename, 0);
	yylineno = 1;
	yyin = f;
	yy_switch_to_buffer(yy_create_buffer(yyin, YY_BUF_SIZE));

	return 1;
}


int pop_input_file(void)
{
	struct incl_file *incl_file;

	if (incl_file_stack == 0)
		return 0;

	fclose(yyin);

	/*
	 * Pop.
	 */
	--incl_depth;
	incl_file = incl_file_stack;
	incl_file_stack = incl_file->prev;

	/*
	 * Recover old context.
	 */
	yy_delete_buffer(YY_CURRENT_BUFFER);
	yy_switch_to_buffer(incl_file->yy_prev_buf);
	yylineno = incl_file->yy_prev_lineno;
	srcpos_filenum = incl_file->filenum;
	yyin = incl_file->file;

	/*
	 * Free old state.
	 */
	free(incl_file);

	if (YY_CURRENT_BUFFER == 0)
		return 0;

	return 1;
}