ael.flex

asterisk 是一个很有知名度开源软件

/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 2006, Digium, Inc.
 *
 * Steve Murphy <[e-mail]>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */
/*! \file
 *
 * \brief Flex scanner description of tokens used in AEL2 .
 *
 */

/*
 * Start with flex options:
 *
 * %x describes the contexts we have: paren, semic and argg, plus INITIAL
 */
%x paren semic argg  comment curlystate wordstate brackstate

/* prefix used for various globally-visible functions and variables.
 * This renames also yywrap, but since we do not use it, we just
 * add option noyywrap to remove it.
 */
%option prefix="ael_yy"
%option noyywrap 8bit

/* I specify this option to suppress flex generating code with ECHO
  in it. This generates compiler warnings in some systems; We've
  seen the fwrite generate Unused variable warnings with 4.1.2 gcc.
  Some systems have tweaked flex ECHO macro to keep the compiler
  happy.  To keep the warning message from getting output, I added
  a default rule at the end of the patterns section */
%option nodefault

/* yyfree normally just frees its arg. It can be null sometimes,
   which some systems will complain about, so, we'll define our own version */
%option noyyfree

/* batch gives a bit more performance if we are using it in
 * a non-interactive mode. We probably don't care much.
 */
%option batch

/* outfile is the filename to be used instead of lex.yy.c */
%option outfile="ael_lex.c"

/*
 * These are not supported in flex 2.5.4, but we need them
 * at the moment:
 * reentrant produces a thread-safe parser. Not 100% sure that
 * we require it, though.
 * bison-bridge passes an additional yylval argument to yylex().
 * bison-locations is probably not needed.
 */
%option reentrant
%option bison-bridge
%option bison-locations

%{
#include "asterisk.h"
ASTERISK_FILE_VERSION(__FILE__, "$Revision: 162272 $")

#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <glob.h>

#if !defined(GLOB_ABORTED)
#define GLOB_ABORTED GLOB_ABEND
#endif

#include "asterisk/logger.h"
#include "asterisk/utils.h"
#include "asterisk/lock.h"
#include "asterisk/hashtab.h"
#include "ael/ael.tab.h"
#include "asterisk/ael_structs.h"

/*
 * A stack to keep track of matching brackets ( [ { } ] )
 */
static char pbcstack[400];	/* XXX missing size checks */
static int pbcpos = 0;
static void pbcpush(char x);
static int pbcpop(char x);
static int parencount = 0;

/*
 * A similar stack to keep track of matching brackets ( [ { } ] ) in word tokens surrounded by ${ ... }
 */
static char pbcstack2[400];	/* XXX missing size checks */
static int pbcpos2 = 0;
static void pbcpush2(char x);
static int pbcpop2(char x);
static int parencount2 = 0;

/*
 * A similar stack to keep track of matching brackets ( [ { } ] ) in word tokens surrounded by $[ ... ]
 */
static char pbcstack3[400];	/* XXX missing size checks */
static int pbcpos3 = 0;
static void pbcpush3(char x);
static int pbcpop3(char x);
static int parencount3 = 0;


/*
 * current line, column and filename, updated as we read the input.
 */
static int my_lineno = 1;	/* current line in the source */
static int my_col = 1;		/* current column in the source */
char *my_file = 0;		/* used also in the bison code */
char *prev_word;		/* XXX document it */

#define MAX_INCLUDE_DEPTH 50

/*
 * flex is not too smart, and generates global functions
 * without prototypes so the compiler may complain.
 * To avoid that, we declare the prototypes here,
 * even though these functions are not used.
 */
int ael_yyget_column  (yyscan_t yyscanner);
void ael_yyset_column (int  column_no , yyscan_t yyscanner);

int ael_yyparse (struct parse_io *);

/*
 * A stack to process include files.
 * As we switch into the new file we need to store the previous
 * state to restore it later.
 */
struct stackelement {
	char *fname;
	int lineno;
	int colno;
	glob_t globbuf;        /* the current globbuf */
	int globbuf_pos;   /* where we are in the current globbuf */
	YY_BUFFER_STATE bufstate;
};

static struct stackelement  include_stack[MAX_INCLUDE_DEPTH];
static int include_stack_index = 0;
static void setup_filestack(char *fnamebuf, int fnamebuf_siz, glob_t *globbuf, int globpos, yyscan_t xscan, int create);

/*
 * if we use the @n feature of bison, we must supply the start/end
 * location of tokens in the structure pointed by yylloc.
 * Simple tokens are just assumed to be on the same line, so
 * the line number is constant, and the column is incremented
 * by the length of the token.
 */
#ifdef FLEX_BETA	/* set for 2.5.33 */

/* compute the total number of lines and columns in the text
 * passed as argument.
 */
static void pbcwhere(const char *text, int *line, int *col )
{
	int loc_line = *line;
	int loc_col = *col;
	char c;
	while ( (c = *text++) ) {
		if ( c == '\t' ) {
			loc_col += 8 - (loc_col % 8);
		} else if ( c == '\n' ) {
			loc_line++;
			loc_col = 1;
		} else
			loc_col++;
	}
	*line = loc_line;
	*col = loc_col;
}

#define	STORE_POS do {							\
		yylloc->first_line = yylloc->last_line = my_lineno;	\
		yylloc->first_column=my_col;				\
		yylloc->last_column=my_col+yyleng-1;			\
		my_col+=yyleng;						\
	} while (0)

#define	STORE_LOC do {					\
		yylloc->first_line = my_lineno;		\
		yylloc->first_column=my_col;		\
		pbcwhere(yytext, &my_lineno, &my_col);	\
		yylloc->last_line = my_lineno;		\
		yylloc->last_column = my_col - 1;	\
	} while (0)
#else
#define	STORE_POS
#define	STORE_LOC
#endif
%}

KEYWORD     (context|abstract|extend|macro|globals|local|ignorepat|switch|if|ifTime|random|regexten|hint|else|goto|jump|return|break|continue|for|while|case|default|pattern|catch|switches|eswitches|includes)

NOPARENS	([^()\[\]\{\}]|\\[()\[\]\{\}])*

NOARGG		([^(),\{\}\[\]]|\\[,()\[\]\{\}])*

NOSEMIC		([^;()\{\}\[\]]|\\[;()\[\]\{\}])*

HIBIT		[\x80-\xff]

%%

\{		{ STORE_POS; return LC;}
\}		{ STORE_POS; return RC;}
\(		{ STORE_POS; return LP;}
\)		{ STORE_POS; return RP;}
\;		{ STORE_POS; return SEMI;}
\=		{ STORE_POS; return EQ;}
\,		{ STORE_POS; return COMMA;}
\:		{ STORE_POS; return COLON;}
\&		{ STORE_POS; return AMPER;}
\|		{ STORE_POS; return BAR;}
\=\>		{ STORE_POS; return EXTENMARK;}
\@		{ STORE_POS; return AT;}
\/\/[^\n]*	{/*comment*/}
context		{ STORE_POS; return KW_CONTEXT;}
abstract	{ STORE_POS; return KW_ABSTRACT;}
extend		{ STORE_POS; return KW_EXTEND;}
macro		{ STORE_POS; return KW_MACRO;};
globals		{ STORE_POS; return KW_GLOBALS;}
local		{ STORE_POS; return KW_LOCAL;}
ignorepat	{ STORE_POS; return KW_IGNOREPAT;}
switch		{ STORE_POS; return KW_SWITCH;}
if		{ STORE_POS; return KW_IF;}
ifTime		{ STORE_POS; return KW_IFTIME;}
random		{ STORE_POS; return KW_RANDOM;}
regexten	{ STORE_POS; return KW_REGEXTEN;}
hint		{ STORE_POS; return KW_HINT;}
else		{ STORE_POS; return KW_ELSE;}
goto		{ STORE_POS; return KW_GOTO;}
jump		{ STORE_POS; return KW_JUMP;}
return		{ STORE_POS; return KW_RETURN;}
break		{ STORE_POS; return KW_BREAK;}
continue	{ STORE_POS; return KW_CONTINUE;}
for		{ STORE_POS; return KW_FOR;}
while		{ STORE_POS; return KW_WHILE;}
case		{ STORE_POS; return KW_CASE;}
default		{ STORE_POS; return KW_DEFAULT;}
pattern		{ STORE_POS; return KW_PATTERN;}
catch		{ STORE_POS; return KW_CATCH;}
switches	{ STORE_POS; return KW_SWITCHES;}
eswitches	{ STORE_POS; return KW_ESWITCHES;}
includes	{ STORE_POS; return KW_INCLUDES;}
"/*"            { BEGIN(comment); my_col += 2; }

<comment>[^*\n]*	{ my_col += yyleng; }
<comment>[^*\n]*\n	{ ++my_lineno; my_col=1;}
<comment>"*"+[^*/\n]*	{ my_col += yyleng; }
<comment>"*"+[^*/\n]*\n 	{ ++my_lineno; my_col=1;}
<comment>"*/"		{ my_col += 2; BEGIN(INITIAL); } /* the nice thing about comments is that you know exactly what ends them */

\n		{ my_lineno++; my_col = 1; }
[ ]+		{ my_col += yyleng; }
[\t]+		{ my_col += (yyleng*8)-(my_col%8); }

({KEYWORD}?[-a-zA-Z0-9'"_/.\<\>\*\+!$#\[\]]|{HIBIT}|(\\.)|(\$\{)|(\$\[)) { 
      /* boy did I open a can of worms when I changed the lexical token "word". 
  	  	 all the above keywords can be used as a beginning to a "word".-
		 before, a "word" would match a longer sequence than the above	 
	     keywords, and all would be well. But now "word" is a single char		
	     and feeds into a statemachine sort of sequence from there on. So...
		 I added the {KEYWORD}? to the beginning of the word match sequence */

		if (!strcmp(yytext,"${")) {
		   	parencount2 = 0;
			pbcpos2 = 0;
			pbcpush2('{');	/* push '{' so the last pcbpop (parencount2 = -1) will succeed */
			BEGIN(curlystate);
			yymore();
		} else if (!strcmp(yytext,"$[")) {
		   	parencount3 = 0;
			pbcpos3 = 0;
			pbcpush3('[');	/* push '[' so the last pcbpop (parencount3 = -1) will succeed */
			BEGIN(brackstate);
			yymore();
		} else {
		    BEGIN(wordstate);
			yymore();
		}
	}

<wordstate>[-a-zA-Z0-9'"_/.\<\>\*\+!$#\[\]] { yymore(); /* Keep going */ }
<wordstate>{HIBIT} { yymore(); /* Keep going */ }
<wordstate>(\\.)  { yymore(); /* Keep Going */ }
<wordstate>(\$\{)  { /* the beginning of a ${} construct. prepare and pop into curlystate */
	   	parencount2 = 0;
		pbcpos2 = 0;
		pbcpush2('{');	/* push '{' so the last pcbpop (parencount2 = -1) will succeed */
		BEGIN(curlystate);
		yymore();
	}
<wordstate>(\$\[)  { /* the beginning of a $[] construct. prepare and pop into brackstate */
	   	parencount3 = 0;
		pbcpos3 = 0;
		pbcpush3('[');	/* push '[' so the last pcbpop (parencount3 = -1) will succeed */
		BEGIN(brackstate);
		yymore();
	}
<wordstate>([^a-zA-Z0-9\x80-\xff\x2d'"_/.\<\>\*\+!$#\[\]]) {
		/* a non-word constituent char, like a space, tab, curly, paren, etc */
		char c = yytext[yyleng-1];
		STORE_POS;
		yylval->str = malloc(yyleng);
		strncpy(yylval->str, yytext, yyleng);
		yylval->str[yyleng-1] = 0;
		unput(c);  /* put this ending char back in the stream */
		BEGIN(0);
		return word;
	}


<curlystate>{NOPARENS}\}	{
		if ( pbcpop2('}') ) {	/* error */
			STORE_LOC;
			ast_log(LOG_ERROR,"File=%s, line=%d, column=%d: Mismatched ')' in expression: %s !\n", my_file, my_lineno, my_col, yytext);
			BEGIN(0);
			yylval->str = malloc(yyleng+1);
			strncpy(yylval->str, yytext, yyleng);
			yylval->str[yyleng] = 0;
			return word;
		}
		parencount2--;
		if ( parencount2 >= 0) {
			yymore();
		} else {
			BEGIN(wordstate); /* Finished with the current ${} construct. Return to word gathering state */
			yymore();
		}
	}

<curlystate>{NOPARENS}[\(\[\{]	{ 
		char c = yytext[yyleng-1];
		if (c == '{')
			parencount2++;
		pbcpush2(c);
		yymore();
	}

<curlystate>{NOPARENS}[\]\)]	{ 
		char c = yytext[yyleng-1];
		if ( pbcpop2(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();
	}


<brackstate>{NOPARENS}\]	{
		if ( pbcpop3(']') ) {	/* error */
			STORE_LOC;
			ast_log(LOG_ERROR,"File=%s, line=%d, column=%d: Mismatched ')' in expression: %s !\n", my_file, my_lineno, my_col, yytext);
			BEGIN(0);
			yylval->str = malloc(yyleng+1);
			strncpy(yylval->str, yytext, yyleng);
			yylval->str[yyleng] = 0;
			return word;
		}
		parencount3--;
		if ( parencount3 >= 0) {
			yymore();
		} else {
			BEGIN(wordstate); /* Finished with the current ${} construct. Return to word gathering state */
			yymore();
		}
	}

<brackstate>{NOPARENS}[\(\[\{]	{ 
		char c = yytext[yyleng-1];
		if (c == '[')
			parencount3++;
		pbcpush3(c);
		yymore();
	}

<brackstate>{NOPARENS}[\}\)]	{ 
		char c = yytext[yyleng-1];
		if ( pbcpop3(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 for arguments of if_head, random_head, switch_head,
	 * for (last statement), while (XXX why not iftime_head ?).
	 * End with the matching parentheses.
	 * A comma at the top level is valid here, unlike in argg where it
	 * is an argument separator so it must be returned as a token.
	 */
<paren>{NOPARENS}\)	{
		if ( pbcpop(')') ) {	/* error */
			STORE_LOC;
			ast_log(LOG_ERROR,"File=%s, line=%d, column=%d: Mismatched ')' in expression: %s !\n", my_file, my_lineno, my_col, yytext);
			BEGIN(0);
			yylval->str = malloc(yyleng+1);
			strncpy(yylval->str, yytext, yyleng);
			yylval->str[yyleng] = 0;
			prev_word = 0;
			return word;
		}
		parencount--;
		if ( parencount >= 0) {
			yymore();
		} else {
			STORE_LOC;
			yylval->str = malloc(yyleng);
			strncpy(yylval->str, yytext, yyleng);
			yylval->str[yyleng-1] = 0;
			unput(')');
			BEGIN(0);
			return word;
		}
	}

<paren>{NOPARENS}[\(\[\{]	{
		char c = yytext[yyleng-1];
		if (c == '(')
			parencount++;
		pbcpush(c);
		yymore();
	}

<paren>{NOPARENS}[\]\}]	{
		char c = yytext[yyleng-1];
		if ( pbcpop(c))  { /* error */