Add utils.h

1 files changed, 32 insertions, 0 deletions

diff --git a/utils.h b/utils.h
new file mode 100644
index 0000000..9c43c88
--- /dev/null
+++ b/utils.h
@@ -0,0 +1,32 @@
+#include <stdlib.h>
+#include <stdint.h>
+
+#ifndef __UTILS_H_
+#define __UTILS_H_
+static inline
+void    setBit(uint8_t x [], uint8_t bit, int32_t pos)
+{
+    int16_t iByte;
+    int16_t iBit;
+
+    iByte   = pos / 8;
+    iBit    = pos % 8;
+    x[iByte] = (x[iByte] & (~(1 << (7 - iBit)))) |
+        (bit << (7 - iBit));
+}
+
+static inline
+void    setBits(uint8_t x[], uint32_t bits,
+        int32_t startPosition, int32_t numBits)
+{
+    int32_t i;
+    uint8_t bit;
+
+    for (i = 0; i < numBits; i ++) {
+        bit = bits & (1 << (numBits - i - 1)) ? 1 : 0;
+        setBit(x, bit, startPosition + i);
+    }
+}
+
+#endif
+