Don't do the "OR together the result of two "ntohl()"s stuff on

platforms that don't support unaligned fetches - just assemble the
64-bit big-endian integer from its constituent bytes.

Improve some comments.

diff --git a/extract.h b/extract.h
index 0d40ed3a19fb1b4e69cbab0a1e4a9dd5b340e19f..80ccc1c66f0930373a26f951feafab0c73ecb3d1 100644 (file)
--- a/extract.h
+++ b/extract.h
@@ -18,11 +18,12 @@
  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * @(#) $Header: /tcpdump/master/tcpdump/extract.h,v 1.21 2004-09-24 18:21:25 guy Exp $ (LBL)
+ * @(#) $Header: /tcpdump/master/tcpdump/extract.h,v 1.22 2004-09-25 06:48:14 guy Exp $ (LBL)
  */
 
-/* Network to host order macros */
-
+/*
+ * Macros to extract possibly-unaligned big-endian integral values.
+ */
 #ifdef LBL_ALIGN
 /*
  * The processor doesn't natively handle unaligned loads.
@@ -54,6 +55,10 @@ typedef struct {
        ((u_int16_t)ntohs(((const unaligned_u_int16_t *)(p))->val))
 #define EXTRACT_32BITS(p) \
        ((u_int32_t)ntohl(((const unaligned_u_int32_t *)(p))->val))
+#define EXTRACT_64BITS(p) \
+       ((u_int64_t)(((u_int64_t)ntohl(((const unaligned_u_int32_t *)(p))->val) << 32 | \
+                    ((u_int64_t)ntohl(((const unaligned_u_int32_t *)(p) + 1)->val)) << 0))
+
 #else /* HAVE___ATTRIBUTE__ */
 /*
  * We don't have __attribute__, so do unaligned loads of big-endian
@@ -68,6 +73,15 @@ typedef struct {
                     (u_int32_t)*((const u_int8_t *)(p) + 1) << 16 | \
                     (u_int32_t)*((const u_int8_t *)(p) + 2) << 8 | \
                     (u_int32_t)*((const u_int8_t *)(p) + 3)))
+#define EXTRACT_LE_64BITS(p) \
+       ((u_int64_t)((u_int64_t)*((const u_int8_t *)(p) + 0) << 56 | \
+                    (u_int64_t)*((const u_int8_t *)(p) + 1) << 48 | \
+                    (u_int64_t)*((const u_int8_t *)(p) + 2) << 40 | \
+                    (u_int64_t)*((const u_int8_t *)(p) + 3) << 32 | \
+                    (u_int64_t)*((const u_int8_t *)(p) + 4) << 24 | \
+                    (u_int64_t)*((const u_int8_t *)(p) + 5) << 16 | \
+                    (u_int64_t)*((const u_int8_t *)(p) + 7) << 8 | \
+                    (u_int64_t)*((const u_int8_t *)(p) + 7)))
 #endif /* HAVE___ATTRIBUTE__ */
 #else /* LBL_ALIGN */
 /*
@@ -78,6 +92,9 @@ typedef struct {
        ((u_int16_t)ntohs(*(const u_int16_t *)(p)))
 #define EXTRACT_32BITS(p) \
        ((u_int32_t)ntohl(*(const u_int32_t *)(p)))
+#define EXTRACT_64BITS(p) \
+       ((u_int64_t)(((u_int64_t)ntohl(*((const u_int32_t *)(p) + 0))) << 32 | \
+                    ((u_int64_t)ntohl(*((const u_int32_t *)(p) + 1))) << 0))
 #endif /* LBL_ALIGN */
 
 #define EXTRACT_24BITS(p) \
@@ -85,12 +102,10 @@ typedef struct {
                     (u_int32_t)*((const u_int8_t *)(p) + 1) << 8 | \
                     (u_int32_t)*((const u_int8_t *)(p) + 2)))
 
-#define EXTRACT_64BITS(p) \
-       ((u_int64_t)(u_int64_t)(EXTRACT_32BITS((p) + 0)) << 32 | \
-                   (u_int64_t)(EXTRACT_32BITS((p) + 4)))
-
-/* Little endian protocol host order macros */
-
+/*
+ * Macros to extract possibly-unaligned little-endian integral values.
+ * XXX - do loads on little-endian machines that support unaligned loads?
+ */
 #define EXTRACT_LE_8BITS(p) (*(p))
 #define EXTRACT_LE_16BITS(p) \
        ((u_int16_t)((u_int16_t)*((const u_int8_t *)(p) + 1) << 8 | \