core: add functions to calculate the length of an int

core/misc.c

@@ -0,0 +1,38 @@
+#include <blue/core/misc.h>
+
+#define LENGTH_RET(v, boundary, len)                                           \
+	if ((v) < (boundary))                                                  \
+		return (len);
+
+size_t b_int_length(intptr_t v)
+{
+	size_t len = 0;
+	if (v < 0) {
+		v *= -1;
+		len++;
+	}
+
+	return len + b_uint_length(v);
+}
+
+size_t b_uint_length(uintptr_t v)
+{
+	LENGTH_RET(v, 10, 1);
+	LENGTH_RET(v, 100, 2);
+	LENGTH_RET(v, 1000, 3);
+	LENGTH_RET(v, 10000, 4);
+	LENGTH_RET(v, 100000, 5);
+	LENGTH_RET(v, 1000000, 6);
+	LENGTH_RET(v, 10000000, 7);
+	LENGTH_RET(v, 100000000, 8);
+	LENGTH_RET(v, 1000000000, 9);
+	LENGTH_RET(v, 10000000000, 10);
+
+	size_t len = 0;
+	while (v > 0) {
+		v /= 10;
+		len++;
+	}
+
+	return len;
+}