+
+
+## ----------------- ##
+## Semantic Values. ##
+## ----------------- ##
+
+
+# b4_symbol_value(VAL, [TYPE])
+# ----------------------------
+# Given a semantic value VAL ($$, $1 etc.), extract its value of type
+# TYPE if TYPE is given, otherwise just return VAL. The result can be
+# used safetly, it is put in parens to avoid nasty precedence issues.
+# TYPE is *not* put in braces, provide some if needed.
+m4_define([b4_symbol_value],
+[($1[]m4_ifval([$2], [.$2]))])
+
+
+
+## --------------------------------------------- ##
+## Defining C functions in both K&R and ANSI-C. ##
+## --------------------------------------------- ##
+
+
+# b4_modern_c
+# -----------
+# A predicate useful in #if to determine whether C is ancient or modern.
+#
+# If __STDC__ is defined, the compiler is modern. IBM xlc 7.0 when run
+# as 'cc' doesn't define __STDC__ (or __STDC_VERSION__) for pedantic
+# reasons, but it defines __C99__FUNC__ so check that as well.
+# Microsoft C normally doesn't define these macros, but it defines _MSC_VER.
+# Consider a C++ compiler to be modern if it defines __cplusplus.
+#
+m4_define([b4_c_modern],
+ [[(defined __STDC__ || defined __C99__FUNC__ \
+ || defined __cplusplus || defined _MSC_VER)]])
+
+# b4_c_function_def(NAME, RETURN-VALUE, [DECL1, NAME1], ...)
+# ----------------------------------------------------------
+# Declare the function NAME.
+m4_define([b4_c_function_def],
+[#if b4_c_modern
+b4_c_ansi_function_def($@)
+#else
+$2
+$1 (b4_c_knr_formal_names(m4_shift2($@)))
+b4_c_knr_formal_decls(m4_shift2($@))
+#endif[]dnl
+])
+
+
+# b4_c_ansi_function_def(NAME, RETURN-VALUE, [DECL1, NAME1], ...)
+# ---------------------------------------------------------------
+# Declare the function NAME in ANSI.
+m4_define([b4_c_ansi_function_def],
+[$2
+$1 (b4_c_ansi_formals(m4_shift2($@)))[]dnl
+])
+
+
+# b4_c_ansi_formals([DECL1, NAME1], ...)
+# --------------------------------------
+# Output the arguments ANSI-C definition.
+m4_define([b4_c_ansi_formals],
+[m4_if([$#], [0], [void],
+ [$#$1], [1], [void],
+ [m4_map_sep([b4_c_ansi_formal], [, ], [$@])])])
+
+m4_define([b4_c_ansi_formal],
+[$1])
+
+
+# b4_c_knr_formal_names([DECL1, NAME1], ...)
+# ------------------------------------------
+# Output the argument names.
+m4_define([b4_c_knr_formal_names],
+[m4_map_sep([b4_c_knr_formal_name], [, ], [$@])])
+
+m4_define([b4_c_knr_formal_name],
+[$2])
+
+
+# b4_c_knr_formal_decls([DECL1, NAME1], ...)
+# ------------------------------------------
+# Output the K&R argument declarations.
+m4_define([b4_c_knr_formal_decls],
+[m4_map_sep([b4_c_knr_formal_decl],
+ [
+],
+ [$@])])
+
+m4_define([b4_c_knr_formal_decl],
+[ $1;])
+
+
+
+## ------------------------------------------------------------ ##
+## Declaring (prototyping) C functions in both K&R and ANSI-C. ##
+## ------------------------------------------------------------ ##
+
+
+# b4_c_function_decl(NAME, RETURN-VALUE, [DECL1, NAME1], ...)
+# -----------------------------------------------------------
+# Declare the function NAME.
+m4_define([b4_c_function_decl],
+[#if b4_c_modern
+b4_c_ansi_function_decl($@)
+#else
+$2 $1 ();
+#endif[]dnl
+])
+
+
+# b4_c_ansi_function_decl(NAME, RETURN-VALUE, [DECL1, NAME1], ...)
+# ----------------------------------------------------------------
+# Declare the function NAME.
+m4_define([b4_c_ansi_function_decl],
+[$2 $1 (b4_c_ansi_formals(m4_shift2($@)));[]dnl
+])
+
+
+
+
+## --------------------- ##
+## Calling C functions. ##
+## --------------------- ##
+
+
+# b4_c_function_call(NAME, RETURN-VALUE, [DECL1, NAME1], ...)
+# -----------------------------------------------------------
+# Call the function NAME with arguments NAME1, NAME2 etc.
+m4_define([b4_c_function_call],
+[$1 (b4_c_args(m4_shift2($@)))[]dnl
+])
+
+
+# b4_c_args([DECL1, NAME1], ...)
+# ------------------------------
+# Output the arguments NAME1, NAME2...
+m4_define([b4_c_args],
+[m4_map_sep([b4_c_arg], [, ], [$@])])
+
+m4_define([b4_c_arg],
+[$2])
+
+
+## ----------- ##
+## Synclines. ##
+## ----------- ##
+
+# b4_sync_start(LINE, FILE)
+# -----------------------
+m4_define([b4_sync_start], [[#]line $1 $2])
+
+
+## -------------- ##
+## User actions. ##
+## -------------- ##
+
+# b4_case(LABEL, STATEMENTS)
+# --------------------------
+m4_define([b4_case],
+[ case $1:
+$2
+b4_syncline([@oline@], [@ofile@])
+ break;])
+
+
+# b4_yydestruct_generate(FUNCTION-DECLARATOR)
+# -------------------------------------------
+# Generate the "yydestruct" function, which declaration is issued using
+# FUNCTION-DECLARATOR, which may be "b4_c_ansi_function_def" for ISO C
+# or "b4_c_function_def" for K&R.
+m4_define_default([b4_yydestruct_generate],
+[[/*-----------------------------------------------.
+| Release the memory associated to this symbol. |
+`-----------------------------------------------*/
+
+/*ARGSUSED*/
+]$1([yydestruct],
+ [static void],
+ [[const char *yymsg], [yymsg]],
+ [[int yytype], [yytype]],
+ [[YYSTYPE *yyvaluep], [yyvaluep]][]dnl
+b4_locations_if( [, [[YYLTYPE *yylocationp], [yylocationp]]])[]dnl
+m4_ifset([b4_parse_param], [, b4_parse_param]))[
+{
+ YYUSE (yyvaluep);
+]b4_locations_if([ YYUSE (yylocationp);
+])dnl
+b4_parse_param_use[]dnl
+[
+ if (!yymsg)
+ yymsg = "Deleting";
+ YY_SYMBOL_PRINT (yymsg, yytype, yyvaluep, yylocationp);
+
+ switch (yytype)
+ {
+]b4_symbol_foreach([b4_symbol_destructor])dnl
+[ default:
+ break;
+ }
+}]dnl
+])
+
+
+# b4_yy_symbol_print_generate(FUNCTION-DECLARATOR)
+# ------------------------------------------------
+# Generate the "yy_symbol_print" function, which declaration is issued using
+# FUNCTION-DECLARATOR, which may be "b4_c_ansi_function_def" for ISO C
+# or "b4_c_function_def" for K&R.
+m4_define_default([b4_yy_symbol_print_generate],
+[[
+/*--------------------------------.
+| Print this symbol on YYOUTPUT. |
+`--------------------------------*/
+
+/*ARGSUSED*/
+]$1([yy_symbol_value_print],
+ [static void],
+ [[FILE *yyoutput], [yyoutput]],
+ [[int yytype], [yytype]],
+ [[YYSTYPE const * const yyvaluep], [yyvaluep]][]dnl
+b4_locations_if([, [[YYLTYPE const * const yylocationp], [yylocationp]]])[]dnl
+m4_ifset([b4_parse_param], [, b4_parse_param]))[
+{
+ if (!yyvaluep)
+ return;
+]b4_locations_if([ YYUSE (yylocationp);
+])dnl
+b4_parse_param_use[]dnl
+[# ifdef YYPRINT
+ if (yytype < YYNTOKENS)
+ YYPRINT (yyoutput, yytoknum[yytype], *yyvaluep);
+# else
+ YYUSE (yyoutput);
+# endif
+ switch (yytype)
+ {
+]b4_symbol_foreach([b4_symbol_printer])dnl
+[ default:
+ break;
+ }
+}
+
+
+/*--------------------------------.
+| Print this symbol on YYOUTPUT. |
+`--------------------------------*/
+
+]$1([yy_symbol_print],
+ [static void],
+ [[FILE *yyoutput], [yyoutput]],
+ [[int yytype], [yytype]],
+ [[YYSTYPE const * const yyvaluep], [yyvaluep]][]dnl
+b4_locations_if([, [[YYLTYPE const * const yylocationp], [yylocationp]]])[]dnl
+m4_ifset([b4_parse_param], [, b4_parse_param]))[
+{
+ if (yytype < YYNTOKENS)
+ YYFPRINTF (yyoutput, "token %s (", yytname[yytype]);
+ else
+ YYFPRINTF (yyoutput, "nterm %s (", yytname[yytype]);
+
+]b4_locations_if([ YY_LOCATION_PRINT (yyoutput, *yylocationp);
+ YYFPRINTF (yyoutput, ": ");
+])dnl
+[ yy_symbol_value_print (yyoutput, yytype, yyvaluep]dnl
+b4_locations_if([, yylocationp])[]b4_user_args[);
+ YYFPRINTF (yyoutput, ")");
+}]dnl