libnftables: Split code into frontend and library

This finally creates the libnftables shared object.

For some reason, this causes two compiler warnings to appear:

| parser_bison.y: In function 'nft_parse':
| parser_bison.y:131:3: warning: implicit declaration of function 'nft_set_debug' [-Wimplicit-function-declaration]
|    nft_set_debug(1, scanner);
|    ^~~~~~~~~~~~~
| parser_bison.c:64:25: warning: implicit declaration of function 'nft_lex' [-Wimplicit-function-declaration]
|  #define yylex           nft_lex
|                          ^
| parser_bison.c:4745:16: note: in expansion of macro 'yylex'
|        yychar = yylex (&yylval, &yylloc, scanner);

So this patch contains a workaround, namely declaring both functions
in src/parser_bison.y. During linking the objects are found, so this is
rather a matter of cosmetics.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 15 insertions, 9 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index 4d613a73..9f7a4bfb 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -27,7 +27,9 @@ parser_bison.o scanner.o: AM_CFLAGS += -Wno-missing-prototypes -Wno-missing-decl
 
 BUILT_SOURCES = parser_bison.h
 
-nft_SOURCES =	main.c				\
+lib_LTLIBRARIES = libnftables.la
+
+libnftables_la_SOURCES =			\
 		rule.c				\
 		statement.c			\
 		datatype.c			\
@@ -59,19 +61,23 @@ nft_SOURCES =	main.c				\
 		parser_bison.y			\
 		libnftables.c
 
-if BUILD_CLI
-nft_SOURCES +=	cli.c
-endif
-
 if BUILD_MINIGMP
 mini-gmp.o: AM_CFLAGS += -Wno-sign-compare
 
-nft_SOURCES +=	mini-gmp.c
+libnftables_la_SOURCES += mini-gmp.c
 endif
 
-nft_LDADD	= ${LIBMNL_LIBS} ${LIBNFTNL_LIBS}
+libnftables_la_LIBADD = ${LIBMNL_LIBS} ${LIBNFTNL_LIBS}
 
 if BUILD_XTABLES
-nft_SOURCES +=	xt.c
-nft_LDADD   +=  ${XTABLES_LIBS}
+libnftables_la_SOURCES += xt.c
+libnftables_la_LIBADD += ${XTABLES_LIBS}
 endif
+
+nft_SOURCES = main.c
+
+if BUILD_CLI
+nft_SOURCES += cli.c
+endif
+
+nft_LDADD = libnftables.la