diff --git a/utf8decode.c b/utf8decode.c
new file mode 100644
index 0000000..4e1ff41
--- /dev/null
+++ b/utf8decode.c
@@ -0,0 +1,56 @@
+// Copyright (c) 2008-2009 Bjoern Hoehrmann <bjoern@hoehrmann.de>
+// See http://bjoern.hoehrmann.de/utf-8/decoder/dfa/ for details.
+
+#include "utf8decode.h"
+
+#define UTF8_ACCEPT 0
+#define UTF8_REJECT 1
+
+static const uint8_t utf8d[] = {
+  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 00..1f
+  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 20..3f
+  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 40..5f
+  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 60..7f
+  1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9, // 80..9f
+  7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, // a0..bf
+  8,8,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, // c0..df
+  0xa,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x4,0x3,0x3, // e0..ef
+  0xb,0x6,0x6,0x6,0x5,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8, // f0..ff
+  0x0,0x1,0x2,0x3,0x5,0x8,0x7,0x1,0x1,0x1,0x4,0x6,0x1,0x1,0x1,0x1, // s0..s0
+  1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,1,1,0,1,0,1,1,1,1,1,1, // s1..s2
+  1,2,1,1,1,1,1,2,1,2,1,1,1,1,1,1,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1, // s3..s4
+  1,2,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1,1,1,1,1,1,3,1,3,1,1,1,1,1,1, // s5..s6
+  1,3,1,1,1,1,1,3,1,3,1,1,1,1,1,1,1,3,1,1,1,1,1,1,1,1,1,1,1,1,1,1, // s7..s8
+};
+
+static uint32_t inline
+decode(uint32_t* state, uint32_t* codep, uint32_t byte) {
+  uint32_t type = utf8d[byte];
+
+  *codep = (*state != UTF8_ACCEPT) ?
+    (byte & 0x3fu) | (*codep << 6) :
+    (0xff >> type) & (byte);
+
+  *state = utf8d[256 + *state*16 + type];
+  return *state;
+}
+
+int
+countCodePoints(uint8_t* s, size_t len) {
+  uint32_t codepoint;
+  uint32_t state = 0;
+  size_t count = 0;
+
+//  for (count = 0; *s; ++s)
+  for (int i = len; i != 0; --i) {
+    //if (!decode(&state, &codepoint, *s))
+    ++s;
+    if (!decode(&state, &codepoint, *s)) {
+      count += 1;
+    }
+  }
+
+  return state != UTF8_ACCEPT;
+//  return state;
+//  return count;
+}
diff --git a/utf8decode.h b/utf8decode.h
new file mode 100644
index 0000000..d4f7f40
--- /dev/null
+++ b/utf8decode.h
@@ -0,0 +1,25 @@
+#ifndef UTF8_DECODE_H
+#define UTF8_DECODE_H
+
+#include <stdlib.h>
+#include <stdint.h>
+
+//inline uint32_t decode(uint32_t* state, uint32_t* codep, uint32_t byte);
+
+extern int countCodePoints(uint8_t* s, size_t count);
+
+/* typedef struct {
+   size_t current_index;
+   size_t total_index;
+   int state;
+   int is_valid;
+   int ends_on_codepoint;
+} utf8_validator_t;
+
+extern void utf8vld_reset (utf8_validator_t* validator);
+
+extern void utf8vld_validate (utf8_validator_t* validator, const uint8_t* data, size_t offset, size_t length);
+
+extern int utf8_valid(const uint8_t* data, size_t len); */
+
+#endif // UTF8_DECODE_H