Fix various problems with inline autocomplete and URLs that change length dur...

base/utf_string_conversions.h

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef BASE_UTF_STRING_CONVERSIONS_H_
 #define BASE_UTF_STRING_CONVERSIONS_H_
 
 #include <string>
 
 #include "base/string16.h"
 #include "base/string_piece.h"
 
+// Like the conversions below, but also takes an offset into the source string,
+// which will be adjusted to point at the same logical place in the result
+// string.  If this isn't possible because it points past the end of the source
+// string or into the middle of a multibyte sequence, it will be set to
+// std::wstring::npos.  |offset_for_adjustment| may be NULL.
+bool WideToUTF8AndAdjustOffset(const wchar_t* src,
+                               size_t src_len,
+                               std::string* output,
+                               size_t* offset_for_adjustment);
+std::string WideToUTF8AndAdjustOffset(const std::wstring& wide,
+                                      size_t* offset_for_adjustment);
+bool UTF8ToWideAndAdjustOffset(const char* src,
+                               size_t src_len,
+                               std::wstring* output,
+                               size_t* offset_for_adjustment);
+std::wstring UTF8ToWideAndAdjustOffset(const base::StringPiece& utf8,
+                                       size_t* offset_for_adjustment);
+
+bool WideToUTF16AndAdjustOffset(const wchar_t* src,
+                                size_t src_len,
+                                string16* output,
+                                size_t* offset_for_adjustment);
+string16 WideToUTF16AndAdjustOffset(const std::wstring& wide,
+                                    size_t* offset_for_adjustment);
+bool UTF16ToWideAndAdjustOffset(const char16* src,
+                                size_t src_len,
+                                std::wstring* output,
+                                size_t* offset_for_adjustment);
+std::wstring UTF16ToWideAndAdjustOffset(const string16& utf16,
+                                        size_t* offset_for_adjustment);
+
 // These convert between UTF-8, -16, and -32 strings. They are potentially slow,
 // so avoid unnecessary conversions. The low-level versions return a boolean
 // indicating whether the conversion was 100% valid. In this case, it will still
 // do the best it can and put the result in the output buffer. The versions that
 // return strings ignore this error and just return the best conversion
 // possible.
 //
 // Note that only the structural validity is checked and non-character
 // codepoints and unassigned are regarded as valid.
 // TODO(jungshik): Consider replacing an invalid input sequence with
 // the Unicode replacement character or adding |replacement_char| parameter.
 // Currently, it's skipped in the ouput, which could be problematic in
 // some situations.
-bool WideToUTF8(const wchar_t* src, size_t src_len, std::string* output);
-std::string WideToUTF8(const std::wstring& wide);
-bool UTF8ToWide(const char* src, size_t src_len, std::wstring* output);
-std::wstring UTF8ToWide(const base::StringPiece& utf8);
+inline bool WideToUTF8(const wchar_t* src,
+                       size_t src_len,
+                       std::string* output) {
+  return WideToUTF8AndAdjustOffset(src, src_len, output, NULL);
+}
+inline std::string WideToUTF8(const std::wstring& wide) {
+  return WideToUTF8AndAdjustOffset(wide, NULL);
+}
+inline bool UTF8ToWide(const char* src, size_t src_len, std::wstring* output) {
+  return UTF8ToWideAndAdjustOffset(src, src_len, output, NULL);
+}
+inline std::wstring UTF8ToWide(const base::StringPiece& utf8) {
+  return UTF8ToWideAndAdjustOffset(utf8, NULL);
+}
 
-bool WideToUTF16(const wchar_t* src, size_t src_len, string16* output);
-string16 WideToUTF16(const std::wstring& wide);
-bool UTF16ToWide(const char16* src, size_t src_len, std::wstring* output);
-std::wstring UTF16ToWide(const string16& utf16);
+inline bool WideToUTF16(const wchar_t* src, size_t src_len, string16* output) {
+  return WideToUTF16AndAdjustOffset(src, src_len, output, NULL);
+}
+inline string16 WideToUTF16(const std::wstring& wide) {
+  return WideToUTF16AndAdjustOffset(wide, NULL);
+}
+inline bool UTF16ToWide(const char16* src, size_t src_len,
+                        std::wstring* output) {
+  return UTF16ToWideAndAdjustOffset(src, src_len, output, NULL);
+}
+inline std::wstring UTF16ToWide(const string16& utf16) {
+  return UTF16ToWideAndAdjustOffset(utf16, NULL);
+}
 
 bool UTF8ToUTF16(const char* src, size_t src_len, string16* output);
 string16 UTF8ToUTF16(const std::string& utf8);
 bool UTF16ToUTF8(const char16* src, size_t src_len, std::string* output);
 std::string UTF16ToUTF8(const string16& utf16);
 
 // We are trying to get rid of wstring as much as possible, but it's too big
 // a mess to do it all at once.  These conversions should be used when we
 // really should just be passing a string16 around, but we haven't finished
 // porting whatever module uses wstring and the conversion is being used as a
 // stopcock.  This makes it easy to grep for the ones that should be removed.
 #if defined(OS_WIN)
 # define WideToUTF16Hack
 # define UTF16ToWideHack
 #else
 # define WideToUTF16Hack WideToUTF16
 # define UTF16ToWideHack UTF16ToWide
 #endif
 
 #endif  // BASE_UTF_STRING_CONVERSIONS_H_