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bird/conf/gen_parser.m4
Ondrej Zajicek a8a64ca0fe Conf: Improve handling of keywords
For whatever reason, parser allocated a symbol for every parsed keyword
in each scope. That wasted time and memory. The effect is worsened with
recent changes allowing local scopes, so keywords often promote soft
scopes (with no symbols) to real scopes.

Do not allocate a symbol for a keyword. Take care of keywords that could
be promoted to symbols (kw_sym) and do it explicitly.
2023-04-27 18:41:01 +02:00

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m4_divert(-1)m4_dnl
#
# BIRD -- Generator of Configuration Grammar
#
# (c) 1998--1999 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
#
# Can be freely distributed and used under the terms of the GNU GPL.
#
# Diversions used:
# 1 includes
# 2 types etc.
# 3 rules
# 4 C code
# Common aliases
m4_define(DNL, `m4_dnl')
# Define macros for defining sections
m4_define(CF_ZONE, `m4_divert($1)/* $2 from m4___file__ */')
m4_define(CF_HDR, `CF_ZONE(1, Headers)')
m4_define(CF_DEFINES, `CF_ZONE(1, Defines)')
m4_define(CF_DECLS, `CF_ZONE(2, Declarations)')
m4_define(CF_GRAMMAR, `CF_ZONE(3, Grammar)')
m4_define(CF_CODE, `CF_ZONE(4, C Code)')
m4_define(CF_END, `m4_divert(-1)')
# Simple iterator
m4_define(CF_itera, `m4_ifelse($#, 1, [[CF_iter($1)]], [[CF_iter($1)[[]]CF_itera(m4_shift($@))]])')
m4_define(CF_iterate, `m4_define([[CF_iter]], m4_defn([[$1]]))CF_itera($2)')
# Keywords act as %token<kw>
m4_define(CF_keywd, `m4_ifdef([[CF_tok_$1]],,[[m4_define([[CF_tok_$1]],1)m4_define([[CF_toks]],CF_toks $1)]])')
m4_define(CF_KEYWORDS, `m4_define([[CF_toks]],[[]])CF_iterate([[CF_keywd]], [[$@]])m4_ifelse(CF_toks,,,%token<kw>[[]]CF_toks
)DNL')
# CLI commands
m4_define(CF_CLI, `m4_define([[CF_cmd]], cmd_[[]]m4_translit($1, [[ ]], _))DNL
m4_divert(2)CF_KEYWORDS(m4_translit($1, [[ ]], [[,]]))
m4_divert(3)cli_cmd: CF_cmd
CF_cmd: $1 $2 END')
m4_define(CF_CLI_CMD, `')
m4_define(CF_CLI_HELP, `')
# ENUM declarations are ignored
m4_define(CF_ENUM, `')
m4_define(CF_ENUM_PX, `')
# After all configuration templates end, we finally generate the grammar file.
m4_m4wrap(`
m4_divert(0)DNL
%{
m4_undivert(1)DNL
%}
m4_undivert(2)DNL
%%
m4_undivert(3)DNL
%%
m4_undivert(4)DNL
')
# As we are processing C source, we must access all M4 primitives via
# m4_* and also set different quoting convention: `[[' and ']]'
m4_changequote([[,]])