maint: prepare forthcoming changes

[bison.git] / data / c.m4

                                                            -*- Autoconf -*-

# C M4 Macros for Bison.

# Copyright (C) 2002, 2004-2012 Free Software Foundation, Inc.

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.


# b4_tocpp(STRING)
# ----------------
# Convert STRING into a valid C macro name.
m4_define([b4_tocpp],
[m4_toupper(m4_bpatsubst(m4_quote($1), [[^a-zA-Z0-9]+], [_]))])


# b4_cpp_guard(FILE)
# ------------------
# A valid C macro name to use as a CPP header guard for FILE.
m4_define([b4_cpp_guard],
[b4_tocpp(m4_defn([b4_prefix])/[$1])])


# b4_cpp_guard_open(FILE)
# b4_cpp_guard_close(FILE)
# ------------------------
# Open/close CPP inclusion guards for FILE.
m4_define([b4_cpp_guard_open],
[#ifndef b4_cpp_guard([$1])
# define b4_cpp_guard([$1])])

m4_define([b4_cpp_guard_close],
[#endif b4_comment([!b4_cpp_guard([$1])])])


## ---------------- ##
## Identification.  ##
## ---------------- ##

# b4_comment_(TEXT, OPEN, CONTINUE, END)
# -------------------------------------
# Put TEXT in comment.  Avoid trailing spaces: don't indent empty lines.
# Avoid adding indentation to the first line, as the indentation comes
# from OPEN.  That's why we don't patsubst([$1], [^\(.\)], [   \1]).
#
# Prefix all the output lines with PREFIX.
m4_define([b4_comment_], [$2[]m4_bpatsubst([$1], [
\(.\)], [
$3\1])$4])


# b4_c_comment(TEXT, [PREFIX])
# ----------------------------
# Put TEXT in comment.  Avoid trailing spaces: don't indent empty lines.
# Avoid adding indentation to the first line, as the indentation comes
# from "/*".  That's why we don't patsubst([$1], [^\(.\)], [   \1]).
#
# Prefix all the output lines with PREFIX.
m4_define([b4_c_comment],
[b4_comment_([$1], [$2/* ], [$2   ], [$2  */])])


# b4_comment(TEXT, [PREFIX])
# --------------------------
# By default, C comments.
m4_define([b4_comment], [b4_c_comment($@)])


# b4_identification
# -----------------
# Depends on individual skeletons to define b4_pure_flag, b4_push_flag, or
# b4_pull_flag if they use the values of the %define variables api.pure or
# api.push-pull.
m4_define([b4_identification],
[[/* Identify Bison output.  */
#define YYBISON 1

/* Bison version.  */
#define YYBISON_VERSION "]b4_version["

/* Skeleton name.  */
#define YYSKELETON_NAME ]b4_skeleton[]m4_ifdef([b4_pure_flag], [[

/* Pure parsers.  */
#define YYPURE ]b4_pure_flag])[]m4_ifdef([b4_push_flag], [[

/* Push parsers.  */
#define YYPUSH ]b4_push_flag])[]m4_ifdef([b4_pull_flag], [[

/* Pull parsers.  */
#define YYPULL ]b4_pull_flag])[
]])


## ---------------- ##
## Default values.  ##
## ---------------- ##

# If the %union is not named, its name is YYSTYPE.
m4_define_default([b4_union_name], [YYSTYPE])

# If the %name-prefix is not given, it is yy.
m4_define_default([b4_prefix], [yy])

## ------------------------ ##
## Pure/impure interfaces.  ##
## ------------------------ ##

# b4_user_args
# ------------
m4_define([b4_user_args],
[m4_ifset([b4_parse_param], [, b4_c_args(b4_parse_param)])])


# b4_parse_param
# --------------
# If defined, b4_parse_param arrives double quoted, but below we prefer
# it to be single quoted.
m4_define([b4_parse_param],
b4_parse_param)


# b4_parse_param_for(DECL, FORMAL, BODY)
# ---------------------------------------
# Iterate over the user parameters, binding the declaration to DECL,
# the formal name to FORMAL, and evaluating the BODY.
m4_define([b4_parse_param_for],
[m4_foreach([$1_$2], m4_defn([b4_parse_param]),
[m4_pushdef([$1], m4_unquote(m4_car($1_$2)))dnl
m4_pushdef([$2], m4_shift($1_$2))dnl
$3[]dnl
m4_popdef([$2])dnl
m4_popdef([$1])dnl
])])

# b4_parse_param_use([VAL], [LOC])
# --------------------------------
# `YYUSE' VAL, LOC if locations are enabled, and all the parse-params.
m4_define([b4_parse_param_use],
[m4_ifvaln([$1], [  YYUSE([$1]);])dnl
b4_locations_if([m4_ifvaln([$2], [  YYUSE ([$2]);])])dnl
b4_parse_param_for([Decl], [Formal], [  YYUSE (Formal);
])dnl
])


## ------------ ##
## Data Types.  ##
## ------------ ##

# b4_int_type(MIN, MAX)
# ---------------------
# Return the smallest int type able to handle numbers ranging from
# MIN to MAX (included).
m4_define([b4_int_type],
[m4_if(b4_ints_in($@,      [0],   [255]), [1], [unsigned char],
       b4_ints_in($@,   [-128],   [127]), [1], [signed char],

       b4_ints_in($@,      [0], [65535]), [1], [unsigned short int],
       b4_ints_in($@, [-32768], [32767]), [1], [short int],

       m4_eval([0 <= $1]),                [1], [unsigned int],

                                               [int])])


# b4_int_type_for(NAME)
# ---------------------
# Return the smallest int type able to handle numbers ranging from
# `NAME_min' to `NAME_max' (included).
m4_define([b4_int_type_for],
[b4_int_type($1_min, $1_max)])


# b4_table_value_equals(TABLE, VALUE, LITERAL)
# --------------------------------------------
# Without inducing a comparison warning from the compiler, check if the
# literal value LITERAL equals VALUE from table TABLE, which must have
# TABLE_min and TABLE_max defined.  YYID must be defined as an identity
# function that suppresses warnings about constant conditions.
m4_define([b4_table_value_equals],
[m4_if(m4_eval($3 < m4_indir([b4_]$1[_min])
               || m4_indir([b4_]$1[_max]) < $3), [1],
       [[YYID (0)]],
       [[((]$2[) == (]$3[))]])])


## ---------##
## Values.  ##
## ---------##


# b4_null_define
# --------------
# Portability issues: define a YY_NULL appropriate for the current
# language (C, C++98, or C++11).
m4_define([b4_null_define],
[# ifndef YY_NULL
#  if defined __cplusplus && 201103L <= __cplusplus
#   define YY_NULL nullptr
#  else
#   define YY_NULL 0
#  endif
# endif[]dnl
])


# b4_null
# -------
# Return a null pointer constant.
m4_define([b4_null], [YY_NULL])

# b4_integral_parser_table_define(TABLE-NAME, CONTENT, COMMENT)
# -------------------------------------------------------------
# Define "yy<TABLE-NAME>" which contents is CONTENT.
m4_define([b4_integral_parser_table_define],
[m4_ifvaln([$3], [b4_c_comment([$3], [  ])])dnl
static const b4_int_type_for([$2]) yy$1[[]] =
{
  $2
};dnl
])


## ------------------------- ##
## Assigning token numbers.  ##
## ------------------------- ##

# b4_token_define(TOKEN-NAME, TOKEN-NUMBER)
# -----------------------------------------
# Output the definition of this token as #define.
m4_define([b4_token_define],
[#define b4_percent_define_get([api.tokens.prefix])$1 $2
])


# b4_token_defines(LIST-OF-PAIRS-TOKEN-NAME-TOKEN-NUMBER)
# -------------------------------------------------------
# Output the definition of the tokens (if there are) as #defines.
m4_define([b4_token_defines],
[m4_if([$#$1], [1], [],
[/* Tokens.  */
m4_map([b4_token_define], [$@])])
])


# b4_token_enum(TOKEN-NAME, TOKEN-NUMBER)
# ---------------------------------------
# Output the definition of this token as an enum.
m4_define([b4_token_enum],
[b4_percent_define_get([api.tokens.prefix])$1 = $2])


# b4_token_enums(LIST-OF-PAIRS-TOKEN-NAME-TOKEN-NUMBER)
# -----------------------------------------------------
# Output the definition of the tokens (if there are) as enums.
m4_define([b4_token_enums],
[m4_if([$#$1], [1], [],
[/* Tokens.  */
#ifndef YYTOKENTYPE
# define YYTOKENTYPE
   /* Put the tokens into the symbol table, so that GDB and other debuggers
      know about them.  */
   enum yytokentype {
m4_map_sep([     b4_token_enum], [,
],
           [$@])
   };
#endif
])])


# b4_token_enums_defines(LIST-OF-PAIRS-TOKEN-NAME-TOKEN-NUMBER)
# -------------------------------------------------------------
# Output the definition of the tokens (if there are any) as enums and, if POSIX
# Yacc is enabled, as #defines.
m4_define([b4_token_enums_defines],
[b4_token_enums($@)b4_yacc_if([b4_token_defines($@)], [])
])


## ----------------- ##
## 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_predicate_case(LABEL, CONDITIONS)
# ------------------------------------
m4_define([b4_predicate_case],
[  case $1:
    if (! ($2)) YYERROR;
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]))[
{
]b4_parse_param_use([yyvaluep], [yylocationp])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]))[
{
  FILE *yyo = yyoutput;
]b4_parse_param_use([yyo], [yylocationp])dnl
[  if (!yyvaluep)
    return;]
dnl glr.c does not feature yytoknum.
m4_if(b4_skeleton, ["yacc.c"],
[[# ifdef YYPRINT
  if (yytype < YYNTOKENS)
    YYPRINT (yyoutput, yytoknum[yytype], *yyvaluep);
# endif
]])dnl
[  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
])

## -------------- ##
## Declarations.  ##
## -------------- ##

# b4_declare_yylstype
# ------------------
# Declarations that might either go into the header (if --defines) or
# in the parser body.  Declare YYSTYPE/YYLTYPE, and yylval/yylloc.
m4_define([b4_declare_yylstype],
[[#if ! defined YYSTYPE && ! defined YYSTYPE_IS_DECLARED
]m4_ifdef([b4_stype],
[[typedef union ]b4_union_name[
{
]b4_user_stype[
} YYSTYPE;
# define YYSTYPE_IS_TRIVIAL 1]],
[m4_if(b4_tag_seen_flag, 0,
[[typedef int YYSTYPE;
# define YYSTYPE_IS_TRIVIAL 1]])])[
# define yystype YYSTYPE /* obsolescent; will be withdrawn */
# define YYSTYPE_IS_DECLARED 1
#endif]b4_locations_if([[

#if ! defined YYLTYPE && ! defined YYLTYPE_IS_DECLARED
typedef struct YYLTYPE
{
  int first_line;
  int first_column;
  int last_line;
  int last_column;
} YYLTYPE;
# define yyltype YYLTYPE /* obsolescent; will be withdrawn */
# define YYLTYPE_IS_DECLARED 1
# define YYLTYPE_IS_TRIVIAL 1
#endif]])

b4_pure_if([], [[extern YYSTYPE ]b4_prefix[lval;
]b4_locations_if([[extern YYLTYPE ]b4_prefix[lloc;]])])[]dnl
])

# b4_declare_yydebug
# ------------------
m4_define([b4_declare_yydebug],
[[/* Enabling traces.  */
#ifndef YYDEBUG
# define YYDEBUG ]b4_parse_trace_if([1], [0])[
#endif
#if YYDEBUG
extern int ]b4_prefix[debug;
#endif][]dnl
])