m4_divert(-1)m4_dnl
#
#	BIRD -- Generator of Configuration Grammar
#
#	(c) 1998 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')

# 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([[,]])