1 files changed, 86 insertions, 0 deletions
diff --git a/Source/cm_utf8.c b/Source/cm_utf8.c
new file mode 100644
index 0000000..2352507
--- /dev/null
+++ b/Source/cm_utf8.c
@@ -0,0 +1,86 @@
+/*============================================================================
+  CMake - Cross Platform Makefile Generator
+  Copyright 2000-2009 Kitware, Inc., Insight Software Consortium
+
+  Distributed under the OSI-approved BSD License (the "License");
+  see accompanying file Copyright.txt for details.
+
+  This software is distributed WITHOUT ANY WARRANTY; without even the
+  implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+  See the License for more information.
+============================================================================*/
+#include "cm_utf8.h"
+
+/*
+  RFC 3629
+  07-bit: 0xxxxxxx
+  11-bit: 110xxxxx 10xxxxxx
+  16-bit: 1110xxxx 10xxxxxx 10xxxxxx
+  21-bit: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
+
+  Pre-RFC Compatibility
+  26-bit: 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx
+  31-bit: 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx
+*/
+
+/* Number of leading ones before a zero in the byte.  */
+static unsigned char const cm_utf8_ones[256] = {
+  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, 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, 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, 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, 1, 1,
+  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 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, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+  3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 7, 8
+};
+
+/* Mask away control bits from bytes with n leading ones.  */
+static unsigned char const cm_utf8_mask[7] = { 0xEF, 0x3F, 0x1F, 0x0F,
+                                               0x07, 0x03, 0x01 };
+
+/* Minimum allowed value when first byte has n leading ones.  */
+static unsigned int const cm_utf8_min[7] = {
+  0, 0, 1u << 7, 1u << 11, 1u << 16, 1u << 21, 1u << 26 /*, 1u<<31 */
+};
+
+const char* cm_utf8_decode_character(const char* first, const char* last,
+                                     unsigned int* pc)
+{
+  /* Count leading ones in the first byte.  */
+  unsigned char c = (unsigned char)*first++;
+  unsigned char const ones = cm_utf8_ones[c];
+  switch (ones) {
+    case 0:
+      *pc = c;
+      return first; /* One-byte character.  */
+    case 1:
+    case 7:
+    case 8:
+      return 0; /* Invalid leading byte.  */
+    default:
+      break;
+  }
+
+  /* Extract bits from this multi-byte character.  */
+  {
+    unsigned int uc = c & cm_utf8_mask[ones];
+    int left;
+    for (left = ones - 1; left && first != last; --left) {
+      c = (unsigned char)*first++;
+      if (cm_utf8_ones[c] != 1) {
+        return 0;
+      }
+      uc = (uc << 6) | (c & cm_utf8_mask[1]);
+    }
+
+    if (left > 0 || uc < cm_utf8_min[ones]) {
+      return 0;
+    }
+
+    *pc = uc;
+    return first;
+  }
+}