Added bitfield functions (not tested)

core/exports/librr/bitfield.h

@@ -0,0 +1,31 @@
+
+#ifndef RR_BITFIELD_H
+#define RR_BITFIELD_H
+
+#include <librr/types.h>
+
+/// @brief Tests whether a bit of an u64_t at a given index from the least significant bit is set.
+/// @param buffer Buffer of which to test the presence of a bit.
+/// @param index Index of the bit of which to test the presence.
+///   The index starts at 0;0 is the least significant bit.
+/// @return Whether the bit in 'buffer' at 'index' was set.
+inline bool_t rr_is_bit_set(u64_t buffer, usz_t index);
+
+/// @brief Sets a bit at a given index from the least significant bit in an u64_t and returns the new u64_t.
+/// @param buffer The buffer to set the 'index'th bit of.
+/// @param index Index of the bit in the buffer (as counted from the least significant bit) to set a bit of.
+///  The index starts with 0; there will always be a bit set (except if the index is greater than 63).
+/// @return The modified buffer with the bit set.
+inline u64_t rr_set_bit(u64_t buffer, usz_t index);
+
+/// @brief Returns a bitfield with a given number of bits set to 1, beginning with the least significant bit.
+/// @param count Number of bits to set
+/// @return The bitfield of which the bits were set.
+u64_t rr_bitpad_lsb(usz_t count);
+
+/// @brief Returns a bitfield with a given number of bits set to 1, beginning with the most significant bit.
+/// @param count Number of bits to set
+/// @return The bitfield of which the bits were set.
+u64_t rr_bitpad_msb(usz_t count);
+
+#endif // RR_BITFIELD_H

core/src-c/bitfield.c

@@ -0,0 +1,29 @@
+#include <librr/bitfield.h>
+
+inline bool_t rr_is_bit_set(u64_t buffer, usz_t index)
+{
+    return !!(buffer & (1 << index));
+}
+
+inline u64_t rr_set_bit(u64_t buffer, usz_t index)
+{
+    return buffer | (1 << index);
+}
+
+u64_t rr_bitpad_lsb(usz_t count)
+{
+    u64_t result = 0;
+    for(usz_t index = 0; index < count; ++index)
+    {
+        result |= 1 << index;
+    }
+}
+
+u64_t rr_bitpad_msb(usz_t count)
+{
+    u64_t result = 0;
+    for(usz_t index = 0; index < count; ++index)
+    {
+        result |= (1 << 63) >> index;
+    }
+}

core/src-c/runes.c

@@ -76,12 +76,12 @@ rune_t rr_extract_utf8(const char *string, usz_t offset, usz_t *increase)
     if(string[offset] == 0x00)
         return ZERO;
     
-    usz_t                       offset_into_rune                = rr_distance_to_last_utf8_rune_start(string, offset);
+    isz_t                       offset_into_rune                = rr_distance_to_last_utf8_rune_start(string, offset);
     if(offset_into_rune < 0)
         return ZERO;
     offset                         -= offset_into_rune;
 
-    usz_t                       rune_length                     = rr_identify_utf8_rune_length(string, offset);
+    isz_t                       rune_length                     = rr_identify_utf8_rune_length(string, offset);
     if(rune_length < 0)
         return ZERO;