ael.flex

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			STORE_LOC;
			ast_log(LOG_ERROR,"File=%s, line=%d, column=%d: Mismatched '%c' in expression!\n",
				my_file, my_lineno, my_col, c);
			BEGIN(0);
			yylval->str = malloc(yyleng+1);
			strncpy(yylval->str, yytext, yyleng);
			yylval->str[yyleng] = 0;
			return word;
		}
		yymore();
	}


	/*
	 * handlers for arguments to a macro or application calls.
	 * We enter this context when we find the initial '(' and
	 * stay here until we close all matching parentheses,
	 * and find the comma (argument separator) or the closing ')'
	 * of the (external) call, which happens when parencount == 0
	 * before the decrement.
	 */
<argg>{NOARGG}[\(\[\{]	  {
		char c = yytext[yyleng-1];
		if (c == '(')
			parencount++;
		pbcpush(c);
		yymore();
	}

<argg>{NOARGG}\)	{
		if ( pbcpop(')') ) { /* error */
			STORE_LOC;
			ast_log(LOG_ERROR,"File=%s, line=%d, column=%d: Mismatched ')' in expression!\n", my_file, my_lineno, my_col);
			BEGIN(0);
			yylval->str = malloc(yyleng+1);
			strncpy(yylval->str, yytext, yyleng);
			yylval->str[yyleng] = 0;
			return word;
		}

		parencount--;
		if( parencount >= 0){
			yymore();
		} else {
			STORE_LOC;
			BEGIN(0);
			if ( !strcmp(yytext, ")") )
				return RP;
			yylval->str = malloc(yyleng);
			strncpy(yylval->str, yytext, yyleng);
			yylval->str[yyleng-1] = '\0'; /* trim trailing ')' */
			unput(')');
			return word;
		}
	}

<argg>{NOARGG}\,	{
		if( parencount != 0) { /* ast_log(LOG_NOTICE,"Folding in a comma!\n"); */
			yymore();
		} else  {
			STORE_LOC;
			if( !strcmp(yytext,"," ) )
				return COMMA;
			yylval->str = malloc(yyleng);
			strncpy(yylval->str, yytext, yyleng);
			yylval->str[yyleng-1] = '\0'; /* trim trailing ',' */
			unput(',');
			return word;
		}
	}

<argg>{NOARGG}[\]\}]	{
		char c = yytext[yyleng-1];
		if ( pbcpop(c) ) { /* error */
			STORE_LOC;
			ast_log(LOG_ERROR,"File=%s, line=%d, column=%d: Mismatched '%c' in expression!\n", my_file, my_lineno, my_col, c);
			BEGIN(0);
			yylval->str = malloc(yyleng+1);
			strncpy(yylval->str, yytext, yyleng);
			yylval->str[yyleng] = '\0';
			return word;
		}
		yymore();
	}

	/*
	 * context used to find tokens in the right hand side of assignments,
	 * or in the first and second operand of a 'for'. As above, match
	 * commas and use ';' as a separator (hence return it as a separate token).
	 */
<semic>{NOSEMIC}[\(\[\{]	{
		char c = yytext[yyleng-1];
		yymore();
		pbcpush(c);
	}

<semic>{NOSEMIC}[\)\]\}]	{
		char c = yytext[yyleng-1];
		if ( pbcpop(c) ) { /* error */
			STORE_LOC;
			ast_log(LOG_ERROR,"File=%s, line=%d, column=%d: Mismatched '%c' in expression!\n", my_file, my_lineno, my_col, c);
			BEGIN(0);
			yylval->str = malloc(yyleng+1);
			strncpy(yylval->str, yytext, yyleng);
			yylval->str[yyleng] = '\0';
			return word;
		}
		yymore();
	}

<semic>{NOSEMIC};	{
		STORE_LOC;
		yylval->str = malloc(yyleng);
		strncpy(yylval->str, yytext, yyleng);
		yylval->str[yyleng-1] = '\0'; /* trim trailing ';' */
		unput(';');
		BEGIN(0);
		return word;
	}

\#include[ \t]+\"[^\"]+\" {
		char fnamebuf[1024],*p1,*p2;
		int glob_ret;
		glob_t globbuf;        /* the current globbuf */
		int globbuf_pos = -1;   /* where we are in the current globbuf */
		globbuf.gl_offs = 0;	/* initialize it to silence gcc */
		
		p1 = strchr(yytext,'"');
		p2 = strrchr(yytext,'"');
		if ( include_stack_index >= MAX_INCLUDE_DEPTH ) {
			ast_log(LOG_ERROR,"File=%s, line=%d, column=%d: Includes nested too deeply! Wow!!! How did you do that?\n", my_file, my_lineno, my_col);
		} else if ( (int)(p2-p1) > sizeof(fnamebuf) - 1 ) {
			ast_log(LOG_ERROR,"File=%s, line=%d, column=%d: Filename is incredibly way too long (%d chars!). Inclusion ignored!\n", my_file, my_lineno, my_col, yyleng - 10);
		} else {
			strncpy(fnamebuf, p1+1, p2-p1-1);
			fnamebuf[p2-p1-1] = 0;
		if (fnamebuf[0] != '/') {
		   char fnamebuf2[1024];
		   snprintf(fnamebuf2,sizeof(fnamebuf2), "%s/%s", (char *)ast_config_AST_CONFIG_DIR, fnamebuf);
		   ast_copy_string(fnamebuf,fnamebuf2,sizeof(fnamebuf));
		}
#ifdef SOLARIS
			glob_ret = glob(fnamebuf, GLOB_NOCHECK, NULL, &globbuf);
#else
			glob_ret = glob(fnamebuf, GLOB_NOMAGIC|GLOB_BRACE, NULL, &globbuf);
#endif
			if (glob_ret == GLOB_NOSPACE) {
				ast_log(LOG_WARNING,
					"Glob Expansion of pattern '%s' failed: Not enough memory\n", fnamebuf);
			} else if (glob_ret  == GLOB_ABORTED) {
				ast_log(LOG_WARNING,
					"Glob Expansion of pattern '%s' failed: Read error\n", fnamebuf);
			} else if (glob_ret  == GLOB_NOMATCH) {
				ast_log(LOG_WARNING,
					"Glob Expansion of pattern '%s' failed: No matches!\n", fnamebuf);
			} else {
			  globbuf_pos = 0;
			}
		}
		if (globbuf_pos > -1) {
			setup_filestack(fnamebuf, sizeof(fnamebuf), &globbuf, 0, yyscanner, 1);
		}
	}


<<EOF>>		{
		char fnamebuf[2048];
		if (include_stack_index > 0 && include_stack[include_stack_index-1].globbuf_pos < include_stack[include_stack_index-1].globbuf.gl_pathc-1) {
			yy_delete_buffer( YY_CURRENT_BUFFER, yyscanner );
			include_stack[include_stack_index-1].globbuf_pos++;
			setup_filestack(fnamebuf, sizeof(fnamebuf), &include_stack[include_stack_index-1].globbuf, include_stack[include_stack_index-1].globbuf_pos, yyscanner, 0);
			/* finish this */			
			
		} else {
			if (include_stack[include_stack_index].fname) {
				free(include_stack[include_stack_index].fname);
				include_stack[include_stack_index].fname = 0;
			}
			if (my_file) {
				free(my_file);
				my_file = 0;
			}
			if ( --include_stack_index < 0 ) {
				yyterminate();
			} else {
				globfree(&include_stack[include_stack_index].globbuf);
				include_stack[include_stack_index].globbuf_pos = -1;
				
				yy_delete_buffer( YY_CURRENT_BUFFER, yyscanner );
				yy_switch_to_buffer(include_stack[include_stack_index].bufstate, yyscanner );
				my_lineno = include_stack[include_stack_index].lineno;
				my_col    = include_stack[include_stack_index].colno;
				my_file   = strdup(include_stack[include_stack_index].fname);
			}
		}
	}

<*>.|\n		{ /* default rule */ ast_log(LOG_ERROR,"Unhandled char(s): %s\n", yytext); }

%%

static void pbcpush(char x)
{
	pbcstack[pbcpos++] = x;
}

void ael_yyfree(void *ptr, yyscan_t yyscanner)
{
	if (ptr)
		free( (char*) ptr );
}

static int pbcpop(char x)
{
	if (   ( x == ')' && pbcstack[pbcpos-1] == '(' )
		|| ( x == ']' && pbcstack[pbcpos-1] == '[' )
		|| ( x == '}' && pbcstack[pbcpos-1] == '{' )) {
		pbcpos--;
		return 0;
	}
	return 1; /* error */
}

static void pbcpush2(char x)
{
	pbcstack2[pbcpos2++] = x;
}

static int pbcpop2(char x)
{
	if (   ( x == ')' && pbcstack2[pbcpos2-1] == '(' )
		|| ( x == ']' && pbcstack2[pbcpos2-1] == '[' )
		|| ( x == '}' && pbcstack2[pbcpos2-1] == '{' )) {
		pbcpos2--;
		return 0;
	}
	return 1; /* error */
}

static void pbcpush3(char x)
{
	pbcstack3[pbcpos3++] = x;
}

static int pbcpop3(char x)
{
	if (   ( x == ')' && pbcstack3[pbcpos3-1] == '(' )
		|| ( x == ']' && pbcstack3[pbcpos3-1] == '[' )
		|| ( x == '}' && pbcstack3[pbcpos3-1] == '{' )) {
		pbcpos3--;
		return 0;
	}
	return 1; /* error */
}

static int c_prevword(void)
{
	char *c = prev_word;
	if (c == NULL)
		return 0;
	while ( *c ) {
		switch (*c) {
		case '{':
		case '[':
		case '(':
			pbcpush(*c);
			break;
		case '}':
		case ']':
		case ')':
			if (pbcpop(*c))
				return 1;
			break;
		}
		c++;
	}
	return 0;
}


/*
 * The following three functions, reset_*, are used in the bison
 * code to switch context. As a consequence, we need to
 * declare them global and add a prototype so that the
 * compiler does not complain.
 *
 * NOTE: yyg is declared because it is used in the BEGIN macros,
 * though that should be hidden as the macro changes
 * depending on the flex options that we use - in particular,
 * %reentrant changes the way the macro is declared;
 * without %reentrant, BEGIN uses yystart instead of yyg
 */

void reset_parencount(yyscan_t yyscanner );
void reset_parencount(yyscan_t yyscanner )
{
	struct yyguts_t * yyg = (struct yyguts_t*)yyscanner;
	parencount = 0;
	pbcpos = 0;
	pbcpush('(');	/* push '(' so the last pcbpop (parencount= -1) will succeed */
	c_prevword();
	BEGIN(paren);
}

void reset_semicount(yyscan_t yyscanner );
void reset_semicount(yyscan_t yyscanner )
{
	struct yyguts_t * yyg = (struct yyguts_t*)yyscanner;
	pbcpos = 0;
	BEGIN(semic);
}

void reset_argcount(yyscan_t yyscanner );
void reset_argcount(yyscan_t yyscanner )
{
	struct yyguts_t * yyg = (struct yyguts_t*)yyscanner;
	parencount = 0;
	pbcpos = 0;
	pbcpush('(');	/* push '(' so the last pcbpop (parencount= -1) will succeed */
	c_prevword();
	BEGIN(argg);
}

/* used elsewhere, but some local vars */
struct pval *ael2_parse(char *filename, int *errors)
{
	struct pval *pval;
	struct parse_io *io;
	char *buffer;
	struct stat stats;
	FILE *fin;

	/* extern int ael_yydebug; */

	io = calloc(sizeof(struct parse_io),1);
	/* reset the global counters */
	prev_word = 0;
	my_lineno = 1;
	include_stack_index=0;
	my_col = 0;
	/* ael_yydebug = 1; */
	ael_yylex_init(&io->scanner);
	fin = fopen(filename,"r");
	if ( !fin ) {
		ast_log(LOG_ERROR,"File %s could not be opened\n", filename);
		*errors = 1;
		return 0;
	}
	if (my_file)
		free(my_file);
	my_file = strdup(filename);
	stat(filename, &stats);
	buffer = (char*)malloc(stats.st_size+2);
	if (fread(buffer, 1, stats.st_size, fin) != stats.st_size) {
		ast_log(LOG_ERROR, "fread() failed: %s\n", strerror(errno));
	}			
	buffer[stats.st_size]=0;
	fclose(fin);

	ael_yy_scan_string (buffer ,io->scanner);
	ael_yyset_lineno(1 , io->scanner);

	/* ael_yyset_in (fin , io->scanner);	OLD WAY */

	ael_yyparse(io);


	pval = io->pval;
	*errors = io->syntax_error_count;

	ael_yylex_destroy(io->scanner);
	free(buffer);
	free(io);

	return pval;
}

static void setup_filestack(char *fnamebuf2, int fnamebuf_siz, glob_t *globbuf, int globpos, yyscan_t yyscanner, int create)
{
	struct yyguts_t * yyg = (struct yyguts_t*)yyscanner;
	int error, i;
	FILE *in1;
	char fnamebuf[2048];

	if (globbuf && globbuf->gl_pathv && globbuf->gl_pathc > 0)
#if defined(STANDALONE) || defined(LOW_MEMORY) || defined(STANDALONE_AEL)
			strncpy(fnamebuf, globbuf->gl_pathv[globpos], fnamebuf_siz);
#else
			ast_copy_string(fnamebuf, globbuf->gl_pathv[globpos], fnamebuf_siz);
#endif
	else {
		ast_log(LOG_ERROR,"Include file name not present!\n");
		return;
	}
	for (i=0; i<include_stack_index; i++) {
		if ( !strcmp(fnamebuf,include_stack[i].fname )) {
			ast_log(LOG_ERROR,"File=%s, line=%d, column=%d: Nice Try!!! But %s has already been included (perhaps by another file), and would cause an infinite loop of file inclusions!!! Include directive ignored\n",
				my_file, my_lineno, my_col, fnamebuf);
			break;
		}
	}
	error = 1;
	if (i == include_stack_index)
		error = 0;	/* we can use this file */
	if ( !error ) {	/* valid file name */
		/* relative vs. absolute */
		if (fnamebuf[0] != '/')
			snprintf(fnamebuf2, fnamebuf_siz, "%s/%s", ast_config_AST_CONFIG_DIR, fnamebuf);
		else
#if defined(STANDALONE) || defined(LOW_MEMORY) || defined(STANDALONE_AEL)
			strncpy(fnamebuf2, fnamebuf, fnamebuf_siz);
#else
			ast_copy_string(fnamebuf2, fnamebuf, fnamebuf_siz);
#endif
		in1 = fopen( fnamebuf2, "r" );

		if ( ! in1 ) {
			ast_log(LOG_ERROR,"File=%s, line=%d, column=%d: Couldn't find the include file: %s; ignoring the Include directive!\n", my_file, my_lineno, my_col, fnamebuf2);
		} else {
			char *buffer;
			struct stat stats;
			stat(fnamebuf2, &stats);
			buffer = (char*)malloc(stats.st_size+1);
			if (fread(buffer, 1, stats.st_size, in1) != stats.st_size) {
				ast_log(LOG_ERROR, "fread() failed: %s\n", strerror(errno));
			}			
			buffer[stats.st_size] = 0;
			ast_log(LOG_NOTICE,"  --Read in included file %s, %d chars\n",fnamebuf2, (int)stats.st_size);
			fclose(in1);
			if (include_stack[include_stack_index].fname) {
			   	free(include_stack[include_stack_index].fname);
				include_stack[include_stack_index].fname = 0;
			}
			include_stack[include_stack_index].fname = strdup(my_file);
			include_stack[include_stack_index].lineno = my_lineno;
			include_stack[include_stack_index].colno = my_col+yyleng;
			if (my_file)
				free(my_file);
			my_file = strdup(fnamebuf2);
			if (create)
				include_stack[include_stack_index].globbuf = *globbuf;

			include_stack[include_stack_index].globbuf_pos = 0;

			include_stack[include_stack_index].bufstate = YY_CURRENT_BUFFER;
			if (create)
				include_stack_index++;
			yy_switch_to_buffer(ael_yy_scan_string (buffer ,yyscanner),yyscanner);
			free(buffer);
			my_lineno = 1;
			my_col = 1;
			BEGIN(INITIAL);
		}
	}
}