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+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc. All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include <google/protobuf/io/strtod.h>
+
+#include <cstdio>
+#include <cstring>
+#include <string>
+
+#include <google/protobuf/stubs/common.h>
+
+namespace google {
+namespace protobuf {
+namespace io {
+
+// ----------------------------------------------------------------------
+// NoLocaleStrtod()
+// This code will make you cry.
+// ----------------------------------------------------------------------
+
+namespace {
+
+// Returns a string identical to *input except that the character pointed to
+// by radix_pos (which should be '.') is replaced with the locale-specific
+// radix character.
+string LocalizeRadix(const char* input, const char* radix_pos) {
+ // Determine the locale-specific radix character by calling sprintf() to
+ // print the number 1.5, then stripping off the digits. As far as I can
+ // tell, this is the only portable, thread-safe way to get the C library
+ // to divuldge the locale's radix character. No, localeconv() is NOT
+ // thread-safe.
+ char temp[16];
+ int size = sprintf(temp, "%.1f", 1.5);
+ GOOGLE_CHECK_EQ(temp[0], '1');
+ GOOGLE_CHECK_EQ(temp[size-1], '5');
+ GOOGLE_CHECK_LE(size, 6);
+
+ // Now replace the '.' in the input with it.
+ string result;
+ result.reserve(strlen(input) + size - 3);
+ result.append(input, radix_pos);
+ result.append(temp + 1, size - 2);
+ result.append(radix_pos + 1);
+ return result;
+}
+
+} // namespace
+
+double NoLocaleStrtod(const char* text, char** original_endptr) {
+ // We cannot simply set the locale to "C" temporarily with setlocale()
+ // as this is not thread-safe. Instead, we try to parse in the current
+ // locale first. If parsing stops at a '.' character, then this is a
+ // pretty good hint that we're actually in some other locale in which
+ // '.' is not the radix character.
+
+ char* temp_endptr;
+ double result = strtod(text, &temp_endptr);
+ if (original_endptr != NULL) *original_endptr = temp_endptr;
+ if (*temp_endptr != '.') return result;
+
+ // Parsing halted on a '.'. Perhaps we're in a different locale? Let's
+ // try to replace the '.' with a locale-specific radix character and
+ // try again.
+ string localized = LocalizeRadix(text, temp_endptr);
+ const char* localized_cstr = localized.c_str();
+ char* localized_endptr;
+ result = strtod(localized_cstr, &localized_endptr);
+ if ((localized_endptr - localized_cstr) >
+ (temp_endptr - text)) {
+ // This attempt got further, so replacing the decimal must have helped.
+ // Update original_endptr to point at the right location.
+ if (original_endptr != NULL) {
+ // size_diff is non-zero if the localized radix has multiple bytes.
+ int size_diff = localized.size() - strlen(text);
+ // const_cast is necessary to match the strtod() interface.
+ *original_endptr = const_cast<char*>(
+ text + (localized_endptr - localized_cstr - size_diff));
+ }
+ }
+
+ return result;
+}
+
+} // namespace io
+} // namespace protobuf
+} // namespace google