Re-committing http://codereview.chromium.org/8736001/ originally committed revision=112305

third_party/libphonenumber/cpp/src/utf/unilib.h

-/**
- * Copyright 2010 Google Inc.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-// Routines to do manipulation of Unicode characters or text
-//
-// The StructurallyValid routines accept buffers of arbitrary bytes.
-// For CoerceToStructurallyValid(), the input buffer and output buffers may
-// point to exactly the same memory.
-//
-// In all other cases, the UTF-8 string must be structurally valid and
-// have all codepoints in the range  U+0000 to U+D7FF or U+E000 to U+10FFFF.
-// Debug builds take a fatal error for invalid UTF-8 input.
-// The input and output buffers may not overlap at all.
-//
-// The char32 routines are here only for convenience; they convert to UTF-8
-// internally and use the UTF-8 routines.
-
-#ifndef UTIL_UTF8_UNILIB_H__
-#define UTIL_UTF8_UNILIB_H__
-
-#include <string>
-#include "base/basictypes.h"
-
-namespace UniLib {
-
-// Returns true unless a surrogate code point
-inline bool IsValidCodepoint(char32 c) {
-  // In the range [0, 0xD800) or [0xE000, 0x10FFFF]
-  return (static_cast<uint32>(c) < 0xD800)
-    || (c >= 0xE000 && c <= 0x10FFFF);
-}
-
-// Table of UTF-8 character lengths, based on first byte
-static const unsigned char kUTF8LenTbl[256] = {
-  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,
-  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,
-
-  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, 4,4,4,4,4,4,4,4
-};
-
-// Return length of a single UTF-8 source character
-inline int OneCharLen(const char* src) {
-  return kUTF8LenTbl[*reinterpret_cast<const uint8*>(src)];
-}
-
-// Return length of a single UTF-8 source character
-inline int OneCharLen(const uint8* src) {
-  return kUTF8LenTbl[*src];
-}
-
-// Return true if this byte is a trailing UTF-8 byte (10xx xxxx)
-inline bool IsTrailByte(char x) {
-  // return (x & 0xC0) == 0x80;
-  // Since trail bytes are always in [0x80, 0xBF], we can optimize:
-  return static_cast<signed char>(x) < -0x40;
-}
-
-// Returns the length in bytes of the prefix of src that is all
-//  interchange valid UTF-8
-int SpanInterchangeValid(const char* src, int byte_length);
-inline int SpanInterchangeValid(const std::string& src) {
-  return SpanInterchangeValid(src.data(), src.size());
-}
-
-// Returns true if the source is all interchange valid UTF-8
-// "Interchange valid" is a stronger than structurally valid --
-// no C0 or C1 control codes (other than CR LF HT FF) and no non-characters.
-inline bool IsInterchangeValid(const char* src, int byte_length) {
-  return (byte_length == SpanInterchangeValid(src, byte_length));
-}
-inline bool IsInterchangeValid(const std::string& src) {
-  return IsInterchangeValid(src.data(), src.size());
-}
-
-}  // namespace UniLib
-
-#endif  // UTIL_UTF8_PUBLIC_UNILIB_H_