flex now generates header file upon request.

6 files changed, 105 insertions, 11 deletions

diff --git a/flex.skl b/flex.skl
index a49f3ba..ba90d71 100644
--- a/flex.skl
+++ b/flex.skl
@@ -256,9 +256,11 @@ struct yy_buffer_state
 	};
 
 %- Standard (non-C++) definition
+%c
 #ifndef YY_REENTRANT
 static YY_BUFFER_STATE yy_current_buffer = 0;
 #endif
+%e
 %*
 
 /* We provide macros for accessing buffer states in case in the
@@ -271,6 +273,7 @@ static YY_BUFFER_STATE yy_current_buffer = 0;
 %- Standard (non-C++) definition
 
 #ifndef YY_REENTRANT
+%c
 /* yy_hold_char holds the character lost when yytext is formed. */
 static char yy_hold_char;
 
@@ -288,7 +291,7 @@ static int yy_start = 0;	/* start state number */
  * instead of setting up a fresh yyin.  A bit of a hack ...
  */
 static int yy_did_buffer_switch_on_eof;
-
+%e
 #endif /* end !YY_REENTRANT */
 
 void yyrestart YY_PROTO(( FILE *input_file YY_LAST_ARG ));
@@ -306,9 +309,11 @@ YY_BUFFER_STATE yy_scan_string YY_PROTO(( yyconst char *yy_str YY_LAST_ARG ));
 YY_BUFFER_STATE yy_scan_bytes YY_PROTO(( yyconst char *bytes, int len YY_LAST_ARG ));
 %*
 
+%c
 static void *yy_flex_alloc YY_PROTO(( yy_size_t YY_LAST_ARG ));
 static void *yy_flex_realloc YY_PROTO(( void *, yy_size_t YY_LAST_ARG ));
 static void yy_flex_free YY_PROTO(( void * YY_LAST_ARG ));
+%e
 
 #define yy_new_buffer yy_create_buffer
 
@@ -333,10 +338,12 @@ static void yy_flex_free YY_PROTO(( void * YY_LAST_ARG ));
 %% yytext/yyin/yyout/yy_state_type/yylineno etc. def's & init go here
 
 %- Standard (non-C++) definition
+%c
 static yy_state_type yy_get_previous_state YY_PROTO(( YY_ONLY_ARG ));
 static yy_state_type yy_try_NUL_trans YY_PROTO(( yy_state_type current_state  YY_LAST_ARG));
 static int yy_get_next_buffer YY_PROTO(( YY_ONLY_ARG ));
 static void yy_fatal_error YY_PROTO(( yyconst char msg[] ));
+%e
 %*
 
 /* Done after the current pattern has been matched and before the
@@ -344,16 +351,17 @@ static void yy_fatal_error YY_PROTO(( yyconst char msg[] ));
  */
 #define YY_DO_BEFORE_ACTION \
 	yytext_ptr = yy_bp; \
-%% code to fiddle yytext and yyleng for yymore() goes here
+%% code to fiddle yytext and yyleng for yymore() goes here \
 	YY_G(yy_hold_char) = *yy_cp; \
 	*yy_cp = '\0'; \
-%% code to copy yytext_ptr to yytext[] goes here, if %array
+%% code to copy yytext_ptr to yytext[] goes here, if %array \
 	YY_G(yy_c_buf_p) = yy_cp;
 
 %*
 
+%c
 %% data tables for the DFA and the user's section 1 definitions go here
-
+%e
 
 #ifndef YY_EXTRA_TYPE
 #define YY_EXTRA_TYPE void *
@@ -406,7 +414,9 @@ struct yy_globals_t
 
     };
 
+%c
 static int yy_init_globals YY_PROTO(( void * ));
+%e
 
 /* This must go here because YYSTYPE and YYLSTYPE are included
  * from bison output in section 1.*/
@@ -489,9 +499,11 @@ extern int yywrap YY_PROTO(( YY_ONLY_ARG ));
 #endif
 
 %-
+%c
 #ifndef YY_NO_UNPUT
 static void yyunput YY_PROTO(( int c, char *buf_ptr  YY_LAST_ARG));
 #endif
+%e
 %*
 
 #ifndef yytext_ptr
@@ -504,19 +516,23 @@ static int yy_flex_strlen YY_PROTO(( yyconst char * YY_LAST_ARG));
 
 #ifndef YY_NO_INPUT
 %- Standard (non-C++) definition
+%c
 #ifdef __cplusplus
 static int yyinput YY_PROTO(( YY_ONLY_ARG ));
 #else
 static int input YY_PROTO(( YY_ONLY_ARG ));
 #endif
+%e
 %*
 #endif
 
 #if YY_STACK_USED
 #ifndef YY_REENTRANT
+%c
 static int yy_start_stack_ptr = 0;
 static int yy_start_stack_depth = 0;
 static int *yy_start_stack = 0;
+%e
 #endif
 #ifndef YY_NO_PUSH_STATE
 static void yy_push_state YY_PROTO(( int new_state YY_LAST_ARG));
@@ -572,8 +588,8 @@ YY_MALLOC_DECL
  */
 #ifndef YY_INPUT
 #define YY_INPUT(buf,result,max_size) \
-%% fread()/read() definition of YY_INPUT goes here unless we're doing C++
-%+ C++ definition
+%% fread()/read() definition of YY_INPUT goes here unless we're doing C++ \
+%+ C++ definition \
 	if ( (result = LexerInput( (char *) buf, max_size )) < 0 ) \
 		YY_FATAL_ERROR( "input in flex scanner failed" );
 %*
@@ -634,6 +650,9 @@ YY_MALLOC_DECL
 #  endif
 #endif
 
+
+extern int yylex YY_PROTO( YY_LEX_ARGS );
+
 #define YY_DECL int yylex YY_LEX_ARGS
 %+ C++ definition
 #define YY_DECL int yyFlexLexer::yylex()
@@ -654,6 +673,7 @@ YY_MALLOC_DECL
 
 %% YY_RULE_SETUP definition goes here
 
+%c
 YY_DECL
 	{
 	register yy_state_type yy_current_state;
@@ -859,8 +879,9 @@ do_action:	/* This label is used only to access EOF actions. */
 	} /* end of action switch */
 		} /* end of scanning one token */
 	} /* end of yylex */
-
+%e
 %+
+%c
 yyFlexLexer::yyFlexLexer( FLEX_STD istream* arg_yyin, FLEX_STD ostream* arg_yyout )
 	{
 	yyin = arg_yyin;
@@ -943,6 +964,7 @@ void yyFlexLexer::LexerOutput( const char* buf, int size )
 	{
 	(void) yyout->write( buf, size );
 	}
+%e
 %*
 
 /* yy_get_next_buffer - try to read in a new buffer
@@ -954,6 +976,7 @@ void yyFlexLexer::LexerOutput( const char* buf, int size )
  */
 
 %-
+%c
 #ifdef YY_USE_PROTOS
 static int yy_get_next_buffer(YY_ONLY_ARG)
 #else
@@ -1090,11 +1113,12 @@ int yyFlexLexer::yy_get_next_buffer()
 
 	return ret_val;
 	}
-
+%e
 
 /* yy_get_previous_state - get the state just before the EOB char was reached */
 
 %-
+%c
 #ifdef YY_USE_PROTOS
 static yy_state_type yy_get_previous_state(YY_ONLY_ARG)
 #else
@@ -2074,3 +2098,4 @@ int main()
 	return 0;
 	}
 #endif
+%e
diff --git a/flexdef.h b/flexdef.h
index 3f6770c..e046288 100644
--- a/flexdef.h
+++ b/flexdef.h
@@ -1046,4 +1046,8 @@ extern struct Buf* buf_strdefine PROTO((struct Buf* buf, const char* str, const
 /* buffer for #define's generated by user-options on cmd line. */
 extern struct Buf userdef_buf;
 
+/* For blocking out code from the header file. */
+#define OUT_BEGIN_CODE() out_str("#ifndef %sIN_HEADER\n",prefix)
+#define OUT_END_CODE() out_str("#endif /* !%sIN_HEADER */\n",prefix);
+
 #endif /* not defined FLEXDEF_H */
diff --git a/main.c b/main.c
index 634b67e..4020305 100644
--- a/main.c
+++ b/main.c
@@ -295,7 +295,7 @@ void check_options()
 			outfilename = outfile_path;
 			}
 
-		prev_stdout = freopen( outfilename, "w", stdout );
+		prev_stdout = freopen( outfilename, "w+", stdout );
 
 		if ( prev_stdout == NULL )
 			lerrsf( _( "could not create %s" ), outfilename );
@@ -395,9 +395,13 @@ void flexend( exit_status )
 int exit_status;
 
 	{
-	int tblsiz;
+	static int called_before = -1; /* prevent infinite recursion. */
+	int tblsiz;	
 	int unlink();
 
+	if( ++called_before )
+		exit( exit_status );
+
 	if ( skelfile != NULL )
 		{
 		if ( ferror( skelfile ) )
@@ -409,6 +413,45 @@ int exit_status;
 				skelname );
 		}
 
+	if ( headerfilename && exit_status == 0 && outfile_created && !ferror(stdout))
+		{
+			/* Copy the file we just wrote to a header file. */
+			#define COPY_SZ 512
+			FILE *header_out;
+			char copybuf[COPY_SZ];
+			int ncopy;
+
+			/* rewind the outfile file. */
+			fflush(stdout);
+			fseek(stdout, 0L, SEEK_SET);
+
+			header_out = fopen(headerfilename, "w");
+			if ( header_out == NULL)
+				lerrsf( _( "could not create %s"), headerfilename );
+
+			fprintf(header_out,
+					"#ifndef %sHEADER_H\n"
+					"#define %sHEADER_H 1\n"
+					"#define %sIN_HEADER 1\n",
+					prefix,prefix,prefix);
+			fflush(header_out);
+
+			while((ncopy=fread(copybuf, 1, COPY_SZ, stdout)) > 0) 
+				if ( fwrite(copybuf, 1, ncopy, header_out) <= 0)
+					break;
+
+			fflush(header_out);
+			fprintf(header_out,
+					"\n"
+					"#undef %sIN_HEADER\n"
+					"#endif /* %sHEADER_H */\n",
+					prefix, prefix);
+
+			if ( ferror( header_out ) )
+				lerrsf( _( "error creating header file %s" ), headerfilename);
+			fclose(header_out);
+		}
+
 	if ( exit_status != 0 && outfile_created )
 		{
 		if ( ferror( stdout ) )
@@ -424,6 +467,7 @@ int exit_status;
 				outfilename );
 		}
 
+
 	if ( backing_up_report && backing_up_file )
 		{
 		if ( num_backing_up == 0 )
@@ -1087,6 +1131,7 @@ _( "Variable trailing context rules entail a large performance penalty\n" ) );
 
 	else
 		{
+		OUT_BEGIN_CODE();
             /* In reentrant scanner, stdinit is handled in flex.skl. */
 		if ( do_stdinit )
 			{
@@ -1117,6 +1162,7 @@ _( "Variable trailing context rules entail a large performance penalty\n" ) );
 			outn( yy_nostdinit );
             outn( "#endif" );
             }
+		OUT_END_CODE();
 		}
 
 	if ( fullspd )
@@ -1133,7 +1179,9 @@ _( "Variable trailing context rules entail a large performance penalty\n" ) );
 	if ( do_yylineno && ! C_plus_plus && ! reentrant )
 		{
 		outn( "extern int yylineno;" );
+		OUT_BEGIN_CODE();
 		outn( "int yylineno = 1;" );
+		OUT_END_CODE();
 		}
 
 	if ( C_plus_plus )
diff --git a/misc.c b/misc.c
index 3f320d9..dc5b6ef 100644
--- a/misc.c
+++ b/misc.c
@@ -794,6 +794,12 @@ void skelout()
 		{ /* copy from skel array */
 		if ( buf[0] == '%' )
 			{ /* control line */
+			/* print the control line as a comment. */
+			if (buf[strlen(buf)-1]=='\\')
+				out_str("/* %s */\\\n", buf);
+			else
+				out_str("/* %s */\n", buf);
+				
 			switch ( buf[1] )
 				{
 				case '%':
@@ -811,6 +817,14 @@ void skelout()
 					do_copy = 1;
 					break;
 
+				case 'c':
+					OUT_BEGIN_CODE();
+					break;
+
+				case 'e':
+					OUT_END_CODE();
+					break;
+
 				default:
 					flexfatal(
 					_( "bad line in skeleton file" ) );
diff --git a/parse.y b/parse.y
index 3a55691..26b646b 100644
--- a/parse.y
+++ b/parse.y
@@ -1,7 +1,7 @@
 /* parse.y - parser for flex input */
 
 %token CHAR NUMBER SECTEND SCDECL XSCDECL NAME PREVCCL EOF_OP
-%token OPTION_OP OPT_OUTFILE OPT_PREFIX OPT_YYCLASS
+%token OPTION_OP OPT_OUTFILE OPT_PREFIX OPT_YYCLASS OPT_HEADER
 
 %token CCE_ALNUM CCE_ALPHA CCE_BLANK CCE_CNTRL CCE_DIGIT CCE_GRAPH
 %token CCE_LOWER CCE_PRINT CCE_PUNCT CCE_SPACE CCE_UPPER CCE_XDIGIT
@@ -196,6 +196,8 @@ option		:  OPT_OUTFILE '=' NAME
 			{ prefix = copy_string( nmstr ); }
 		|  OPT_YYCLASS '=' NAME
 			{ yyclass = copy_string( nmstr ); }
+		|  OPT_HEADER '=' NAME
+			{ headerfilename = copy_string( nmstr ); }
 		;
 
 sect2		:  sect2 scon initforrule flexrule '\n'
diff --git a/scan.l b/scan.l
index 22b2e48..ac58aaf 100644
--- a/scan.l
+++ b/scan.l
@@ -301,6 +301,7 @@ LEXOPT		[aceknopr]
 	outfile		return OPT_OUTFILE;
 	prefix		return OPT_PREFIX;
 	yyclass		return OPT_YYCLASS;
+	header      return OPT_HEADER;
 
 	\"[^"\n]*\"	{
 			strcpy( nmstr, yytext + 1 );