Avoid type-punned compiler warnings for the byteorder.h macros

by using inline functions for the 4-char <-> uint32 conversions.

1 files changed, 57 insertions, 9 deletions

diff --git a/byteorder.h b/byteorder.h
index 6dd9b459..146b861f 100644
--- a/byteorder.h
+++ b/byteorder.h
@@ -19,6 +19,7 @@
  */
 
 #undef CAREFUL_ALIGNMENT
+#undef AVOID_BYTEORDER_INLINE
 
 /* We know that the x86 can handle misalignment and has the same
  * byte order (LSB-first) as the 32-bit numbers we transmit. */
@@ -32,21 +33,68 @@
 
 #define CVAL(buf,pos) (((unsigned char *)(buf))[pos])
 #define UVAL(buf,pos) ((uint32)CVAL(buf,pos))
-#define SCVAL(buf,pos,val) (CVAL(buf,pos) = (val))
 
 #if CAREFUL_ALIGNMENT
+
 #define PVAL(buf,pos) (UVAL(buf,pos)|UVAL(buf,(pos)+1)<<8)
 #define IVAL(buf,pos) (PVAL(buf,pos)|PVAL(buf,(pos)+2)<<16)
 #define SSVALX(buf,pos,val) (CVAL(buf,pos)=(val)&0xFF,CVAL(buf,pos+1)=(val)>>8)
 #define SIVALX(buf,pos,val) (SSVALX(buf,pos,val&0xFFFF),SSVALX(buf,pos+2,val>>16))
 #define SIVAL(buf,pos,val) SIVALX((buf),(pos),((uint32)(val)))
-#else
-/* this handles things for architectures like the 386 that can handle
-   alignment errors */
-/*
-   WARNING: This section is dependent on the length of int32
-   being correct. set CAREFUL_ALIGNMENT if it is not.
-*/
+
+#define IVALu(buf,pos) IVAL(buf,pos)
+#define SIVALu(buf,pos,val) SIVAL(buf,pos,val)
+
+#else /* !CAREFUL_ALIGNMENT */
+
+/* This handles things for architectures like the 386 that can handle alignment errors.
+ * WARNING: This section is dependent on the length of an int32 (and thus a uint32)
+ * being correct (4 bytes)!  Set CAREFUL_ALIGNMENT if it is not. */
+
+# ifdef AVOID_BYTEORDER_INLINE
+
 #define IVAL(buf,pos) (*(uint32 *)((char *)(buf) + (pos)))
 #define SIVAL(buf,pos,val) IVAL(buf,pos)=((uint32)(val))
-#endif
+
+#define IVALu(buf,pos) IVAL(buf,pos)
+#define SIVALu(buf,pos,val) SIVAL(buf,pos,val)
+
+# else /* !AVOID_BYTEORDER_INLINE */
+
+static inline uint32
+IVALu(const uchar *buf, int pos)
+{
+	union {
+		const uchar *b;
+		const uint32 *num;
+	} u;
+	u.b = buf + pos;
+	return *u.num;
+}
+
+static inline void
+SIVALu(uchar *buf, int pos, uint32 val)
+{
+	union {
+		uchar *b;
+		uint32 *num;
+	} u;
+	u.b = buf + pos;
+	*u.num = val;
+}
+
+static inline uint32
+IVAL(const char *buf, int pos)
+{
+	return IVALu((uchar*)buf, pos);
+}
+
+static inline void
+SIVAL(char *buf, int pos, uint32 val)
+{
+	SIVALu((uchar*)buf, pos, val);
+}
+
+# endif /* !AVOID_BYTEORDER_INLINE */
+
+#endif /* !CAREFUL_ALIGNMENT */