]> git.ozlabs.org Git - ccan/blobdiff - ccan/endian/endian.h
endian: Fix cpu_to_be64 on big-endian
[ccan] / ccan / endian / endian.h
index 81db5d948f368505375a81f32fee7591d065973d..0c99cc802db0e0acac0668d11d305fe89b4b5aed 100644 (file)
+/* CC0 (Public domain) - see LICENSE file for details */
 #ifndef CCAN_ENDIAN_H
 #define CCAN_ENDIAN_H
 #include <stdint.h>
 #include "config.h"
 
 /**
- * swab_u16 - reverse bytes in a uint16_t value.
+ * BSWAP_16 - reverse bytes in a constant uint16_t value.
+ * @val: constant value whose bytes to swap.
+ *
+ * Designed to be usable in constant-requiring initializers.
+ *
+ * Example:
+ *     struct mystruct {
+ *             char buf[BSWAP_16(0x1234)];
+ *     };
+ */
+#define BSWAP_16(val)                          \
+       ((((uint16_t)(val) & 0x00ff) << 8)      \
+        | (((uint16_t)(val) & 0xff00) >> 8))
+
+/**
+ * BSWAP_32 - reverse bytes in a constant uint32_t value.
+ * @val: constant value whose bytes to swap.
+ *
+ * Designed to be usable in constant-requiring initializers.
+ *
+ * Example:
+ *     struct mystruct {
+ *             char buf[BSWAP_32(0xff000000)];
+ *     };
+ */
+#define BSWAP_32(val)                                  \
+       ((((uint32_t)(val) & 0x000000ff) << 24)         \
+        | (((uint32_t)(val) & 0x0000ff00) << 8)                \
+        | (((uint32_t)(val) & 0x00ff0000) >> 8)                \
+        | (((uint32_t)(val) & 0xff000000) >> 24))
+
+/**
+ * BSWAP_64 - reverse bytes in a constant uint64_t value.
+ * @val: constantvalue whose bytes to swap.
+ *
+ * Designed to be usable in constant-requiring initializers.
+ *
+ * Example:
+ *     struct mystruct {
+ *             char buf[BSWAP_64(0xff00000000000000ULL)];
+ *     };
+ */
+#define BSWAP_64(val)                                          \
+       ((((uint64_t)(val) & 0x00000000000000ffULL) << 56)      \
+        | (((uint64_t)(val) & 0x000000000000ff00ULL) << 40)    \
+        | (((uint64_t)(val) & 0x0000000000ff0000ULL) << 24)    \
+        | (((uint64_t)(val) & 0x00000000ff000000ULL) << 8)     \
+        | (((uint64_t)(val) & 0x000000ff00000000ULL) >> 8)     \
+        | (((uint64_t)(val) & 0x0000ff0000000000ULL) >> 24)    \
+        | (((uint64_t)(val) & 0x00ff000000000000ULL) >> 40)    \
+        | (((uint64_t)(val) & 0xff00000000000000ULL) >> 56))
+
+#if HAVE_BYTESWAP_H
+#include <byteswap.h>
+#else
+/**
+ * bswap_16 - reverse bytes in a uint16_t value.
  * @val: value whose bytes to swap.
+ *
+ * Example:
+ *     // Output contains "1024 is 4 as two bytes reversed"
+ *     printf("1024 is %u as two bytes reversed\n", bswap_16(1024));
  */
-static inline uint16_t swab_u16(uint16_t val)
+static inline uint16_t bswap_16(uint16_t val)
 {
-       return ((val & (uint16_t)0x00ffU) << 8)
-               | ((val & (uint16_t)0xff00U) >> 8);
+       return BSWAP_16(val);
 }
 
 /**
- * swab_u32 - reverse bytes in a uint32_t value.
+ * bswap_32 - reverse bytes in a uint32_t value.
  * @val: value whose bytes to swap.
+ *
+ * Example:
+ *     // Output contains "1024 is 262144 as four bytes reversed"
+ *     printf("1024 is %u as four bytes reversed\n", bswap_32(1024));
  */
-static inline uint32_t swab_u32(uint32_t val)
+static inline uint32_t bswap_32(uint32_t val)
 {
-       return ((val & (uint32_t)0x000000ffUL) << 24)
-               | ((val & (uint32_t)0x0000ff00UL) <<  8)
-               | ((val & (uint32_t)0x00ff0000UL) >>  8)
-               | ((val & (uint32_t)0xff000000UL) >> 24);
+       return BSWAP_32(val);
 }
+#endif /* !HAVE_BYTESWAP_H */
 
+#if !HAVE_BSWAP_64
 /**
- * swab_u64 - reverse bytes in a uint64_t value.
+ * bswap_64 - reverse bytes in a uint64_t value.
  * @val: value whose bytes to swap.
+ *
+ * Example:
+ *     // Output contains "1024 is 1125899906842624 as eight bytes reversed"
+ *     printf("1024 is %llu as eight bytes reversed\n",
+ *             (unsigned long long)bswap_64(1024));
  */
-static inline uint64_t swab_u64(uint64_t val)
+static inline uint64_t bswap_64(uint64_t val)
 {
-       return ((val & (uint64_t)0x00000000000000ffULL) << 56)
-               | ((val & (uint64_t)0x000000000000ff00ULL) << 40)
-               | ((val & (uint64_t)0x0000000000ff0000ULL) << 24)
-               | ((val & (uint64_t)0x00000000ff000000ULL) <<  8)
-               | ((val & (uint64_t)0x000000ff00000000ULL) >>  8)
-               | ((val & (uint64_t)0x0000ff0000000000ULL) >> 24)
-               | ((val & (uint64_t)0x00ff000000000000ULL) >> 40)
-               | ((val & (uint64_t)0xff00000000000000ULL) >> 56);
+       return BSWAP_64(val);
 }
+#endif
 
 /* Sanity check the defines.  We don't handle weird endianness. */
 #if !HAVE_LITTLE_ENDIAN && !HAVE_BIG_ENDIAN
@@ -48,160 +110,237 @@ static inline uint64_t swab_u64(uint64_t val)
 #error "Can't compile for both big and little endian."
 #endif
 
+#ifdef __CHECKER__
+/* sparse needs forcing to remove bitwise attribute from ccan/short_types */
+#define ENDIAN_CAST __attribute__((force))
+#define ENDIAN_TYPE __attribute__((bitwise))
+#else
+#define ENDIAN_CAST
+#define ENDIAN_TYPE
+#endif
+
+typedef uint64_t ENDIAN_TYPE leint64_t;
+typedef uint64_t ENDIAN_TYPE beint64_t;
+typedef uint32_t ENDIAN_TYPE leint32_t;
+typedef uint32_t ENDIAN_TYPE beint32_t;
+typedef uint16_t ENDIAN_TYPE leint16_t;
+typedef uint16_t ENDIAN_TYPE beint16_t;
+
+#if HAVE_LITTLE_ENDIAN
+/**
+ * CPU_TO_LE64 - convert a constant uint64_t value to little-endian
+ * @native: constant to convert
+ */
+#define CPU_TO_LE64(native) ((ENDIAN_CAST leint64_t)(native))
+
+/**
+ * CPU_TO_LE32 - convert a constant uint32_t value to little-endian
+ * @native: constant to convert
+ */
+#define CPU_TO_LE32(native) ((ENDIAN_CAST leint32_t)(native))
+
+/**
+ * CPU_TO_LE16 - convert a constant uint16_t value to little-endian
+ * @native: constant to convert
+ */
+#define CPU_TO_LE16(native) ((ENDIAN_CAST leint16_t)(native))
+
+/**
+ * LE64_TO_CPU - convert a little-endian uint64_t constant
+ * @le_val: little-endian constant to convert
+ */
+#define LE64_TO_CPU(le_val) ((ENDIAN_CAST uint64_t)(le_val))
+
+/**
+ * LE32_TO_CPU - convert a little-endian uint32_t constant
+ * @le_val: little-endian constant to convert
+ */
+#define LE32_TO_CPU(le_val) ((ENDIAN_CAST uint32_t)(le_val))
+
+/**
+ * LE16_TO_CPU - convert a little-endian uint16_t constant
+ * @le_val: little-endian constant to convert
+ */
+#define LE16_TO_CPU(le_val) ((ENDIAN_CAST uint16_t)(le_val))
+
+#else /* ... HAVE_BIG_ENDIAN */
+#define CPU_TO_LE64(native) ((ENDIAN_CAST leint64_t)BSWAP_64(native))
+#define CPU_TO_LE32(native) ((ENDIAN_CAST leint32_t)BSWAP_32(native))
+#define CPU_TO_LE16(native) ((ENDIAN_CAST leint16_t)BSWAP_16(native))
+#define LE64_TO_CPU(le_val) BSWAP_64((ENDIAN_CAST uint64_t)le_val)
+#define LE32_TO_CPU(le_val) BSWAP_32((ENDIAN_CAST uint32_t)le_val)
+#define LE16_TO_CPU(le_val) BSWAP_16((ENDIAN_CAST uint16_t)le_val)
+#endif /* HAVE_BIG_ENDIAN */
+
+#if HAVE_BIG_ENDIAN
+/**
+ * CPU_TO_BE64 - convert a constant uint64_t value to big-endian
+ * @native: constant to convert
+ */
+#define CPU_TO_BE64(native) ((ENDIAN_CAST beint64_t)(native))
+
+/**
+ * CPU_TO_BE32 - convert a constant uint32_t value to big-endian
+ * @native: constant to convert
+ */
+#define CPU_TO_BE32(native) ((ENDIAN_CAST beint32_t)(native))
+
+/**
+ * CPU_TO_BE16 - convert a constant uint16_t value to big-endian
+ * @native: constant to convert
+ */
+#define CPU_TO_BE16(native) ((ENDIAN_CAST beint16_t)(native))
+
+/**
+ * BE64_TO_CPU - convert a big-endian uint64_t constant
+ * @le_val: big-endian constant to convert
+ */
+#define BE64_TO_CPU(le_val) ((ENDIAN_CAST uint64_t)(le_val))
+
+/**
+ * BE32_TO_CPU - convert a big-endian uint32_t constant
+ * @le_val: big-endian constant to convert
+ */
+#define BE32_TO_CPU(le_val) ((ENDIAN_CAST uint32_t)(le_val))
+
+/**
+ * BE16_TO_CPU - convert a big-endian uint16_t constant
+ * @le_val: big-endian constant to convert
+ */
+#define BE16_TO_CPU(le_val) ((ENDIAN_CAST uint16_t)(le_val))
+
+#else /* ... HAVE_LITTLE_ENDIAN */
+#define CPU_TO_BE64(native) ((ENDIAN_CAST beint64_t)BSWAP_64(native))
+#define CPU_TO_BE32(native) ((ENDIAN_CAST beint32_t)BSWAP_32(native))
+#define CPU_TO_BE16(native) ((ENDIAN_CAST beint16_t)BSWAP_16(native))
+#define BE64_TO_CPU(le_val) BSWAP_64((ENDIAN_CAST uint64_t)le_val)
+#define BE32_TO_CPU(le_val) BSWAP_32((ENDIAN_CAST uint32_t)le_val)
+#define BE16_TO_CPU(le_val) BSWAP_16((ENDIAN_CAST uint16_t)le_val)
+#endif /* HAVE_LITTE_ENDIAN */
+
+
 /**
  * cpu_to_le64 - convert a uint64_t value to little-endian
  * @native: value to convert
  */
-static inline uint64_t cpu_to_le64(uint64_t native)
+static inline leint64_t cpu_to_le64(uint64_t native)
 {
-#if HAVE_LITTLE_ENDIAN
-       return native;
-#else
-       return swab_u64(native);
-#endif
+       return CPU_TO_LE64(native);
 }
 
 /**
  * cpu_to_le32 - convert a uint32_t value to little-endian
  * @native: value to convert
  */
-static inline uint32_t cpu_to_le32(uint32_t native)
+static inline leint32_t cpu_to_le32(uint32_t native)
 {
-#if HAVE_LITTLE_ENDIAN
-       return native;
-#else
-       return swab_u32(native);
-#endif
+       return CPU_TO_LE32(native);
 }
 
 /**
  * cpu_to_le16 - convert a uint16_t value to little-endian
  * @native: value to convert
  */
-static inline uint16_t cpu_to_le16(uint16_t native)
+static inline leint16_t cpu_to_le16(uint16_t native)
 {
-#if HAVE_LITTLE_ENDIAN
-       return native;
-#else
-       return swab_u16(native);
-#endif
+       return CPU_TO_LE16(native);
 }
 
 /**
  * le64_to_cpu - convert a little-endian uint64_t value
  * @le_val: little-endian value to convert
  */
-static inline uint64_t le64_to_cpu(uint64_t le_val)
+static inline uint64_t le64_to_cpu(leint64_t le_val)
 {
-#if HAVE_LITTLE_ENDIAN
-       return le_val;
-#else
-       return swab_u64(le_val);
-#endif
+       return LE64_TO_CPU(le_val);
 }
 
 /**
  * le32_to_cpu - convert a little-endian uint32_t value
  * @le_val: little-endian value to convert
  */
-static inline uint32_t le32_to_cpu(uint32_t le_val)
+static inline uint32_t le32_to_cpu(leint32_t le_val)
 {
-#if HAVE_LITTLE_ENDIAN
-       return le_val;
-#else
-       return swab_u32(le_val);
-#endif
+       return LE32_TO_CPU(le_val);
 }
 
 /**
  * le16_to_cpu - convert a little-endian uint16_t value
  * @le_val: little-endian value to convert
  */
-static inline uint16_t le16_to_cpu(uint16_t le_val)
+static inline uint16_t le16_to_cpu(leint16_t le_val)
 {
-#if HAVE_LITTLE_ENDIAN
-       return le_val;
-#else
-       return swab_u16(le_val);
-#endif
+       return LE16_TO_CPU(le_val);
 }
 
 /**
  * cpu_to_be64 - convert a uint64_t value to big endian.
  * @native: value to convert
  */
-static inline uint64_t cpu_to_be64(uint64_t native)
+static inline beint64_t cpu_to_be64(uint64_t native)
 {
-#if HAVE_LITTLE_ENDIAN
-       return swab_u64(native);
-#else
-       return native;
-#endif
+       return CPU_TO_BE64(native);
 }
 
 /**
  * cpu_to_be32 - convert a uint32_t value to big endian.
  * @native: value to convert
  */
-static inline uint32_t cpu_to_be32(uint32_t native)
+static inline beint32_t cpu_to_be32(uint32_t native)
 {
-#if HAVE_LITTLE_ENDIAN
-       return swab_u32(native);
-#else
-       return native;
-#endif
+       return CPU_TO_BE32(native);
 }
 
 /**
  * cpu_to_be16 - convert a uint16_t value to big endian.
  * @native: value to convert
  */
-static inline uint16_t cpu_to_be16(uint16_t native)
+static inline beint16_t cpu_to_be16(uint16_t native)
 {
-#if HAVE_LITTLE_ENDIAN
-       return swab_u16(native);
-#else
-       return native;
-#endif
+       return CPU_TO_BE16(native);
 }
 
 /**
  * be64_to_cpu - convert a big-endian uint64_t value
  * @be_val: big-endian value to convert
  */
-static inline uint64_t be64_to_cpu(uint64_t be_val)
+static inline uint64_t be64_to_cpu(beint64_t be_val)
 {
-#if HAVE_LITTLE_ENDIAN
-       return swab_u64(be_val);
-#else
-       return be_val;
-#endif
+       return BE64_TO_CPU(be_val);
 }
 
 /**
  * be32_to_cpu - convert a big-endian uint32_t value
  * @be_val: big-endian value to convert
  */
-static inline uint32_t be32_to_cpu(uint32_t be_val)
+static inline uint32_t be32_to_cpu(beint32_t be_val)
 {
-#if HAVE_LITTLE_ENDIAN
-       return swab_u32(be_val);
-#else
-       return be_val;
-#endif
+       return BE32_TO_CPU(be_val);
 }
 
 /**
  * be16_to_cpu - convert a big-endian uint16_t value
  * @be_val: big-endian value to convert
  */
-static inline uint16_t be16_to_cpu(uint16_t be_val)
+static inline uint16_t be16_to_cpu(beint16_t be_val)
 {
-#if HAVE_LITTLE_ENDIAN
-       return swab_u16(be_val);
-#else
-       return be_val;
-#endif
+       return BE16_TO_CPU(be_val);
 }
 
+/* Whichever they include first, they get these definitions. */
+#ifdef CCAN_SHORT_TYPES_H
+/**
+ * be64/be32/be16 - 64/32/16 bit big-endian representation.
+ */
+typedef beint64_t be64;
+typedef beint32_t be32;
+typedef beint16_t be16;
+
+/**
+ * le64/le32/le16 - 64/32/16 bit little-endian representation.
+ */
+typedef leint64_t le64;
+typedef leint32_t le32;
+typedef leint16_t le16;
+#endif
 #endif /* CCAN_ENDIAN_H */