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.

1 files changed, 2 insertions, 2 deletions

diff --git a/sll.h b/sll.h
index b2d7c779..ad0d7b59 100644
--- a/sll.h
+++ b/sll.h
@@ -35,7 +35,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- * @(#) $Header: /tcpdump/master/tcpdump/sll.h,v 1.6 2002-11-09 17:19:32 itojun Exp $ (LBL)
+ * @(#) $Header: /tcpdump/master/tcpdump/sll.h,v 1.7 2002-12-11 07:14:11 guy Exp $ (LBL)
  */
 
 /*
@@ -88,7 +88,7 @@ struct sll_header {
 	u_int16_t	sll_halen;	/* link-layer address length */
 	u_int8_t	sll_addr[SLL_ADDRLEN];	/* link-layer address */
 	u_int16_t	sll_protocol;	/* protocol */
-} __attribute__((packed));
+};
 
 /*
  * The LINUX_SLL_ values for "sll_pkttype"; these correspond to the