tcpdump/token.h
guy fcc82f451d The "__attribute__((packed))" tag on structures causes some files not to
compile with Sun C, as "interface.h" isn't being included before the
structures are being declared.

Furthermore, in the files that Sun C *can* compile, it doesn't cause Sun
C to generate code that's safe with unaligned accesses, as
"__attribute__" is defined as a do-nothing macro with compilers that
don't support it.

Therefore, we get rid of that tag on the structures to which it was
added, and instead use "EXTRACT_16BIT()" and "EXTRACT_32BIT()" to fetch
16-bit and 32-bit big-endian quantities from packets.  We also fix some
other references to multi-byte quantities to get rid of code that tries
to do unaligned loads on platforms that don't support them.

We also throw in a hack that makes those macros use
"__attribute__((packed))" on structures containing only one 16-bit or
32-bit integer to get the compiler to generate unaligned-safe code
rather than doing it by hand.  (GCC on SPARC produces the same code that
doing it by hand does; I don't know if GCC on any other big-endian
strict-alignment processor generates better code for that case.  On
little-endian processors, as "ntohs()" and "ntohl()" might be functions,
that might actually produce worse code.)

Fix some places to use "%u" rather than "%d" to print unsigned
quantities.
2002-12-11 07:13:49 +00:00

53 lines
2.3 KiB
C

/* @(#) $Header: /tcpdump/master/tcpdump/token.h,v 1.6 2002-12-11 07:14:12 guy Exp $ (LBL) */
/*
* Copyright (c) 1998, Larry Lile
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice unmodified, this list of conditions, and the following
* disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#define TOKEN_HDRLEN 14
#define TOKEN_RING_MAC_LEN 6
#define ROUTING_SEGMENT_MAX 16
#define IS_SOURCE_ROUTED(trp) ((trp)->token_shost[0] & 0x80)
#define FRAME_TYPE(trp) (((trp)->token_fc & 0xC0) >> 6)
#define TOKEN_FC_LLC 1
#define BROADCAST(trp) ((ntohs((trp)->token_rcf) & 0xE000) >> 13)
#define RIF_LENGTH(trp) ((ntohs((trp)->token_rcf) & 0x1f00) >> 8)
#define DIRECTION(trp) ((ntohs((trp)->token_rcf) & 0x0080) >> 7)
#define LARGEST_FRAME(trp) ((ntohs((trp)->token_rcf) & 0x0070) >> 4)
#define RING_NUMBER(trp, x) ((ntohs((trp)->token_rseg[x]) & 0xfff0) >> 4)
#define BRIDGE_NUMBER(trp, x) ((ntohs((trp)->token_rseg[x]) & 0x000f))
#define SEGMENT_COUNT(trp) ((int)((RIF_LENGTH(trp) - 2) / 2))
struct token_header {
u_int8_t token_ac;
u_int8_t token_fc;
u_int8_t token_dhost[TOKEN_RING_MAC_LEN];
u_int8_t token_shost[TOKEN_RING_MAC_LEN];
u_int16_t token_rcf;
u_int16_t token_rseg[ROUTING_SEGMENT_MAX];
};