include/bitopts: Use the operating system byteswapping functions

The swap macros are already in libc.

Co-Author: Cristian Rodríguez <crrodriguez@opensuse.org>
Signed-off-by: Karel Zak <kzak@redhat.com>

1 files changed, 97 insertions, 63 deletions

diff --git a/include/bitops.h b/include/bitops.h
index 81375d060..9738dd726 100644
--- a/include/bitops.h
+++ b/include/bitops.h
@@ -2,12 +2,107 @@
 #define BITOPS_H
 
 #include <stdint.h>
+#include <sys/param.h>
+
+#if defined(HAVE_BYTESWAP_H)
+# include <byteswap.h>
+#endif
+
+#if defined(HAVE_ENDIAN_H)
+#  include <endian.h>
+#elif defined(HAVE_SYS_ENDIAN_H)	/* BSDs have them here */
+#  include <sys/endian.h>
+#endif
+
+#if defined(__OpenBSD__)
+# include <sys/types.h>
+# define be16toh(x) betoh16(x)
+# define be32toh(x) betoh32(x)
+# define be64toh(x) betoh64(x)
+#endif
 
 /*
- * Bit map related macros. Usually provided by libc.
+ * Fallbacks
  */
-#include <sys/param.h>
+#ifndef bswap_16
+# define bswap_16(x)   ((((x) & 0x00FF) << 8) | \
+			(((x) & 0xFF00) >> 8))
+#endif
+
+#ifndef bswap_32
+# define bswap_32(x)   ((((x) & 0x000000FF) << 24) | \
+			(((x) & 0x0000FF00) << 8)  | \
+			(((x) & 0x00FF0000) >> 8)  | \
+			(((x) & 0xFF000000) >> 24))
+#endif
+
+#ifndef bswap_64
+# define bswap_64(x) ((((x) & 0x00000000000000FFULL) << 56) | \
+                      (((x) & 0x000000000000FF00ULL) << 40) | \
+                      (((x) & 0x0000000000FF0000ULL) << 24) | \
+                      (((x) & 0x00000000FF000000ULL) << 8)  | \
+                      (((x) & 0x000000FF00000000ULL) >> 8)  | \
+                      (((x) & 0x0000FF0000000000ULL) >> 24) | \
+                      (((x) & 0x00FF000000000000ULL) >> 40) | \
+                      (((x) & 0xFF00000000000000ULL) >> 56))
+#endif
+
+#ifndef htobe16
+# if !defined(WORDS_BIGENDIAN)
+#  define htobe16(x) bswap_16 (x)
+#  define htole16(x) (x)
+#  define be16toh(x) bswap_16 (x)
+#  define le16toh(x) (x)
+#  define htobe32(x) bswap_32 (x)
+#  define htole32(x) (x)
+#  define be32toh(x) bswap_32 (x)
+#  define le32toh(x) (x)
+#  define htobe64(x) bswap_64 (x)
+#  define htole64(x) (x)
+#  define be64toh(x) bswap_64 (x)
+#  define le64toh(x) (x)
+# else
+#  define htobe16(x) (x)
+#  define htole16(x) bswap_16 (x)
+#  define be16toh(x) (x)
+#  define le16toh(x) bswap_16 (x)
+#  define htobe32(x) (x)
+#  define htole32(x) bswap_32 (x)
+#  define be32toh(x) (x)
+#  define le32toh(x) bswap_32 (x)
+#  define htobe64(x) (x)
+#  define htole64(x) bswap_64 (x)
+#  define be64toh(x) (x)
+#  define le64toh(x) bswap_64 (x)
+# endif
+#endif
 
+/*
+ * Byte swab macros (based on linux/byteorder/swab.h)
+ */
+#define swab16(x) bswap_16(x)
+#define swab32(x) bswap_32(x)
+#define swab64(x) bswap_64(x)
+
+#define cpu_to_le16(x) ((uint16_t) htole16(x))
+#define cpu_to_le32(x) ((uint32_t) htole32(x))
+#define cpu_to_le64(x) ((uint64_t) htole64(x))
+
+#define cpu_to_be16(x) ((uint16_t) htobe16(x))
+#define cpu_to_be32(x) ((uint32_t) htobe32(x))
+#define cpu_to_be64(x) ((uint64_t) htobe64(x))
+
+#define le16_to_cpu(x) ((uint16_t) le16toh(x))
+#define le32_to_cpu(x) ((uint32_t) le32toh(x))
+#define le64_to_cpu(x) ((uint64_t) le64toh(x))
+
+#define be16_to_cpu(x) ((uint16_t) be16toh(x))
+#define be32_to_cpu(x) ((uint32_t) be32toh(x))
+#define be64_to_cpu(x) ((uint64_t) be64toh(x))
+
+/*
+ * Bit map related macros. Usually provided by libc.
+ */
 #ifndef NBBY
 # define NBBY            CHAR_BIT
 #endif
@@ -19,66 +114,5 @@
 # define isclr(a,i)	(((a)[(i)/NBBY] & (1<<((i)%NBBY))) == 0)
 #endif
 
-/*
- * Byte swab macros (based on linux/byteorder/swab.h)
- */
-#define swab16(x) \
-	((uint16_t)( \
-		(((uint16_t)(x) & (uint16_t)0x00ffU) << 8) | \
-		(((uint16_t)(x) & (uint16_t)0xff00U) >> 8) ))
-
-#define swab32(x) \
-	((uint32_t)( \
-		(((uint32_t)(x) & (uint32_t)0x000000ffUL) << 24) | \
-		(((uint32_t)(x) & (uint32_t)0x0000ff00UL) <<  8) | \
-		(((uint32_t)(x) & (uint32_t)0x00ff0000UL) >>  8) | \
-		(((uint32_t)(x) & (uint32_t)0xff000000UL) >> 24) ))
-
-#define swab64(x) \
-	((uint64_t)( \
-		(uint64_t)(((uint64_t)(x) & (uint64_t)0x00000000000000ffULL) << 56) | \
-		(uint64_t)(((uint64_t)(x) & (uint64_t)0x000000000000ff00ULL) << 40) | \
-		(uint64_t)(((uint64_t)(x) & (uint64_t)0x0000000000ff0000ULL) << 24) | \
-		(uint64_t)(((uint64_t)(x) & (uint64_t)0x00000000ff000000ULL) <<  8) | \
-	        (uint64_t)(((uint64_t)(x) & (uint64_t)0x000000ff00000000ULL) >>  8) | \
-		(uint64_t)(((uint64_t)(x) & (uint64_t)0x0000ff0000000000ULL) >> 24) | \
-		(uint64_t)(((uint64_t)(x) & (uint64_t)0x00ff000000000000ULL) >> 40) | \
-		(uint64_t)(((uint64_t)(x) & (uint64_t)0xff00000000000000ULL) >> 56) ))
-
-
-#ifdef WORDS_BIGENDIAN
-
-#define cpu_to_le16(x) swab16(x)
-#define cpu_to_le32(x) swab32(x)
-#define cpu_to_le64(x) swab64(x)
-#define cpu_to_be16(x) ((uint16_t)(x))
-#define cpu_to_be32(x) ((uint32_t)(x))
-#define cpu_to_be64(x) ((uint64_t)(x))
-
-#define le16_to_cpu(x) swab16(x)
-#define le32_to_cpu(x) swab32(x)
-#define le64_to_cpu(x) swab64(x)
-#define be16_to_cpu(x) ((uint16_t)(x))
-#define be32_to_cpu(x) ((uint32_t)(x))
-#define be64_to_cpu(x) ((uint64_t)(x))
-
-#else /* !WORDS_BIGENDIAN */
-
-#define cpu_to_le16(x) ((uint16_t)(x))
-#define cpu_to_le32(x) ((uint32_t)(x))
-#define cpu_to_le64(x) ((uint64_t)(x))
-#define cpu_to_be16(x) swab16(x)
-#define cpu_to_be32(x) swab32(x)
-#define cpu_to_be64(x) swab64(x)
-
-#define le16_to_cpu(x) ((uint16_t)(x))
-#define le32_to_cpu(x) ((uint32_t)(x))
-#define le64_to_cpu(x) ((uint64_t)(x))
-#define be16_to_cpu(x) swab16(x)
-#define be32_to_cpu(x) swab32(x)
-#define be64_to_cpu(x) swab64(x)
-
-#endif /* WORDS_BIGENDIAN */
-
 #endif /* BITOPS_H */