netfilter: nf_tables: Eliminate duplicated code in nf_tables_table_enable()

If something fails in nf_tables_table_enable(), it unregisters the
chains. But the rollback code is the same as nf_tables_table_disable()
almostly, except there is one counter check.  Now create one wrapper
function to eliminate the duplicated codes.

Signed-off-by: Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

path: root/ipv4.h

#ifndef IPV4_H
#define IPV4_H

#include <asm/byteorder.h>

#include "built_in.h"

struct ipv4hdr {
#if defined(__LITTLE_ENDIAN_BITFIELD)
	__extension__ uint8_t h_ihl:4,
			      h_version:4;
#elif defined (__BIG_ENDIAN_BITFIELD)
	__extension__ uint8_t h_version:4,
			      h_ihl:4;
#else
# error "Please fix <asm/byteorder.h>"
#endif
	uint8_t h_tos;
	uint16_t h_tot_len;
	uint16_t h_id;
	uint16_t h_frag_off;
	uint8_t h_ttl;
	uint8_t h_protocol;
	uint16_t h_check;
	uint32_t h_saddr;
	uint32_t h_daddr;
} __packed;

#endif /* IPV4_H */