%x NORMAL HEREDOC QUOTED QUOTED2

%{
/*
 * $Header: /usr/build/vile/vile/filters/RCS/sh-filt.l,v 1.38 2000/10/27 02:02:49 tom Exp $
 *
 * Filter to add vile "attribution" sequences to selected bits of Shell script.
 */

#include <filters.h>

DefineFilter("sh");

#define isQuote(ch) (ch != 0 && strchr("\\'\"", ch) != 0)

static char *Action_attr;
static char *Comment_attr;
static char *Error_attr;
static char *Ident_attr;
static char *Number_attr;
static char *String_attr;

static char *here_tag;
static unsigned here_len;
static int here_exp;

static void
save_here(char *text, int length)
{
    char *s = here_tag = do_alloc(here_tag, length, &here_len);

    here_exp = 1;
    while (length--) {
	if (isQuote(*text)) {
	    here_exp = 0;
	} else if (strchr(" \t", *text) != 0) {
	    if (s != here_tag)
		break;
	} else if (strchr("<->", *text) == 0) {
	    *s++ = *text;
	}
	text++;
    }
    *s = 0;
}

static int
got_here(char *text, int length)
{
    int pass, j, k;

    for (pass = 0; pass < 2; pass++) {
	for (j = k = 0; j < length; j++) {
	    if (isQuote(text[j])) {
		if (pass)
		    flt_bfr_embed(text + j, 1, Error_attr);
	    } else {
		if (text[j] != here_tag[k++])
		    return 0;
		if (pass)
		    flt_bfr_append(text + j, 1);
	    }
	}
    }
    return 1;
}

static void
init_filter(int before GCC_UNUSED)
{
}

static void
do_filter(FILE *input)
{
    yyin = input;

    Action_attr  = class_attr(NAME_ACTION);
    Comment_attr = class_attr(NAME_COMMENT);
    Error_attr   = class_attr(NAME_ERROR);
    Ident_attr   = class_attr(NAME_IDENT2);
    Number_attr  = class_attr(NAME_NUMBER);
    String_attr  = class_attr(NAME_LITERAL);

    here_exp = 0;

    BEGIN(NORMAL);
    while (yylex() > 0) {
    }
    flt_bfr_error();
}

%}

SPACE		[ \t]

SSTRING		\'([^']|\n)*\'

NAME		[a-zA-Z0-9_]

WILDCARD	(\?|\*)
WILDNAME	({NAME}|{WILDCARD})
FILENAME	(([./]{WILDNAME}+)|({WILDNAME}+[./]{WILDNAME}*)|({NAME}*{WILDCARD})|\.+\/+)+

ACTION		[\.`{}]
IDENT		[a-zA-Z_]{NAME}*
QIDENT		[^ $\t\n]+
IDENT0		[-]+[0-9]*[a-zA-Z_-]+[0-9a-zA-Z_-]*
IDENT1		\${NAME}+
IDENT2		\$\{[^\}]*\}
IDENTEQLS	[a-zA-Z_]{NAME}*=
IDENTX		\$[\*@#\?\$!-]

INTEGER		[-+]?([0-9]+)

%%

<NORMAL>{IDENT0}	|
<NORMAL>{FILENAME}	{ ECHO; /* exclude from other classes */ }

<NORMAL>{IDENT}		{ WriteToken(keyword_attr(yytext)); }

<NORMAL>"#"[^\n]*	{ WriteToken(Comment_attr); }

<NORMAL>^{SPACE}*:	|
<NORMAL>{ACTION}	{ WriteToken(Action_attr); }

<NORMAL>{INTEGER}	{ WriteToken(Number_attr); }

<NORMAL>{IDENT1}	|
<NORMAL>{IDENT2}	|
<NORMAL>{IDENTX}	{ WriteToken(Ident_attr); }

<NORMAL>{IDENTEQLS}	{ flt_puts(yytext, yyleng-1, Ident_attr); flt_putc('='); }

<NORMAL>\\.		|
<NORMAL>{SSTRING}	{ WriteToken(String_attr); }
<NORMAL>\"		{ BeginQuote(QUOTED, String_attr); }

<NORMAL>\<\<[-]?{SPACE}*{QIDENT} {
			    save_here(yytext, yyleng);
			    BeginQuote(HEREDOC, String_attr);
			}
<HEREDOC>\\\$		{ flt_bfr_append(yytext, yyleng); }
<HEREDOC>{IDENT1}	|
<HEREDOC>{IDENT2}	{
			    if (here_exp) {
				flt_bfr_embed(yytext, yyleng, Ident_attr);
			    } else {
				flt_bfr_append(yytext, yyleng);
			    }
			}
<HEREDOC>^{QIDENT}$	{
			    if (got_here(yytext, yyleng)) {
				flt_bfr_finish();
				BEGIN(NORMAL);
			    } else {
				flt_bfr_append(yytext, yyleng);
			    }
			}
<HEREDOC>[^\n\$]+	{ flt_bfr_append(yytext, yyleng); }
<HEREDOC>\n		{ flt_bfr_append(yytext, yyleng); }
<HEREDOC>.		{ flt_bfr_append(yytext, yyleng); }

<QUOTED>\\		{ flt_bfr_embed(yytext, yyleng, Action_attr); BEGIN(QUOTED2); }
<QUOTED>{IDENT1}	|
<QUOTED>{IDENT2}	{ flt_bfr_embed(yytext, yyleng, Ident_attr); }
<QUOTED>[^\n\\\"]+	{ flt_bfr_append(yytext, yyleng); }
<QUOTED>\n		{ flt_bfr_append(yytext, yyleng); }
<QUOTED>\"		{ FinishQuote(NORMAL); }

<QUOTED2>(.|\n)		{ flt_bfr_embed(yytext, yyleng, Action_attr); BEGIN(QUOTED); }
