--- /dev/null
+/*
+** Copyright 2011 Double Precision, Inc.
+** See COPYING for distribution information.
+**
+*/
+
+#include "unicode_config.h"
+#include "unicode.h"
+
+#define BLOCK_SIZE 256
+
+uint8_t unicode_tab_lookup(unicode_char ch,
+ const size_t *unicode_indextab,
+ size_t unicode_indextab_sizeof,
+ const uint8_t (*unicode_rangetab)[2],
+ const uint8_t *unicode_classtab,
+ uint8_t uclass)
+{
+ size_t cl=ch / BLOCK_SIZE;
+
+ if (cl < unicode_indextab_sizeof-1)
+ {
+ const size_t start_pos=unicode_indextab[cl];
+ const uint8_t (*p)[2]=unicode_rangetab + start_pos;
+ size_t b=0, e=unicode_indextab[cl+1] - start_pos;
+ uint8_t chmodcl= ch & (BLOCK_SIZE-1);
+
+ while (b < e)
+ {
+ size_t n=b + (e-b)/2;
+
+ if (chmodcl >= p[n][0])
+ {
+ if (chmodcl <= p[n][1])
+ {
+ uclass=unicode_classtab[start_pos+n];
+ break;
+ }
+ b=n+1;
+ }
+ else
+ {
+ e=n;
+ }
+ }
+ }
+
+ return uclass;
+}