0
0
mirror of https://gitlab.nic.cz/labs/bird.git synced 2024-11-09 20:58:44 +00:00
bird/conf/gen_parser.m4
Martin Mares bc2fb68098 Parse CLI commands. We use the same parser as for configuration files (because
we want to allow filter and similar complex constructs to be used in commands
and we should avoid code duplication), only with CLI_MARKER token prepended
before the whole input.

Defined macro CF_CLI(cmd, args, help) for defining CLI commands in .Y files.
The first argument specifies the command itself, the remaining two arguments
are copied to the help file (er, will be copied after the help file starts
to exist). This macro automatically creates a skeleton rule for the command,
you only need to append arguments as in:

	CF_CLI(STEAL MONEY, <$>, [[Steal <$> US dollars or equivalent in any other currency]]): NUM {
		cli_msg(0, "%d$ stolen", $3);
	} ;

Also don't forget to reset lexer state between inputs.
1999-10-31 17:47:47 +00:00

70 lines
1.9 KiB
Plaintext

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)/* $2 from m4___file__ */')
m4_define(CF_HDR, `CF_ZONE(1, Headers)')
m4_define(CF_DECLS, `CF_ZONE(2, Declarations)')
m4_define(CF_GRAMMAR, `CF_ZONE(3, Grammar)')
m4_define(CF_CODE, `CF_ZONE(4, C Code)')
m4_define(CF_END, `m4_divert(-1)')
# Simple iterator
m4_define(CF_itera, `m4_ifelse($#, 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 untyped %token
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[[]]CF_toks
)DNL')
# Dynamic syntax rules
m4_define(CF_dyn_rules,)
m4_define(CF_ADDTO, `m4_define([[CF_rule_$1]],m4_ifdef([[CF_rule_$1]],CF_rule_$1 | ,[[m4_define([[CF_dyn_rules]],CF_dyn_rules[[CF_RULE($1)
]])]])$2)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)CF_ADDTO(cli_cmd, CF_cmd)
CF_cmd: $1 ')
# 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
/* Dynamic rules */
m4_define(CF_RULE, [[$1: CF_rule_$1 ;]])
CF_dyn_rules
%%
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([[,]])