libsigrok-internal.h: add 24bit little endian reader helper

Add another endianess conversion helper which reads 24bit values in
little endian format.

diff --git a/src/libsigrok-internal.h b/src/libsigrok-internal.h
index 465a16e965ace8cf426cbafb866d92005e67f61f..8925cbffbf78eb855d835354c66a7cca297862ad 100644 (file)
--- a/src/libsigrok-internal.h
+++ b/src/libsigrok-internal.h
@@ -142,6 +142,23 @@ static inline int16_t read_i16le(const uint8_t *p)
 }
 #define RL16S(x) read_i16le((const uint8_t *)(x))
 
+/**
+ * Read a 24 bits little endian unsigned integer out of memory.
+ * @param x a pointer to the input memory
+ * @return the corresponding unsigned integer
+ */
+static inline uint32_t read_u24le(const uint8_t *p)
+{
+       uint32_t u;
+
+       u = 0;
+       u <<= 8; u |= p[2];
+       u <<= 8; u |= p[1];
+       u <<= 8; u |= p[0];
+
+       return u;
+}
+
 /**
  * Read a 32 bits big endian unsigned integer out of memory.
  * @param x a pointer to the input memory
@@ -499,6 +516,23 @@ static inline uint32_t read_u32be_inc(const uint8_t **p)
        return v;
 }
 
+/**
+ * Read unsigned 24bit integer from raw memory (little endian format), increment read position.
+ * @param[in, out] p Pointer into byte stream.
+ * @return Retrieved integer value, unsigned.
+ */
+static inline uint32_t read_u24le_inc(const uint8_t **p)
+{
+       uint32_t v;
+
+       if (!p || !*p)
+               return 0;
+       v = read_u24le(*p);
+       *p += 3 * sizeof(uint8_t);
+
+       return v;
+}
+
 /**
  * Read unsigned 32bit integer from raw memory (little endian format), increment read position.
  * @param[in, out] p Pointer into byte stream.