1 /* 2 * Copyright (C) 2016 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include "android-base/errors.h" 18 19 #include <windows.h> 20 21 #include "android-base/stringprintf.h" 22 #include "android-base/strings.h" 23 #include "android-base/utf8.h" 24 25 // A Windows error code is a DWORD. It's simpler to use an int error code for 26 // both Unix and Windows if possible, but if this fails we'll need a different 27 // function signature for each. 28 static_assert(sizeof(int) >= sizeof(DWORD), 29 "Windows system error codes are too large to fit in an int."); 30 31 namespace android { 32 namespace base { 33 34 static constexpr DWORD kErrorMessageBufferSize = 256; 35 36 std::string SystemErrorCodeToString(int int_error_code) { 37 WCHAR msgbuf[kErrorMessageBufferSize]; 38 DWORD error_code = int_error_code; 39 DWORD flags = FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS; 40 DWORD len = FormatMessageW(flags, nullptr, error_code, 0, msgbuf, 41 kErrorMessageBufferSize, nullptr); 42 if (len == 0) { 43 return android::base::StringPrintf( 44 "Error %lu while retrieving message for error %lu", GetLastError(), 45 error_code); 46 } 47 48 // Convert UTF-16 to UTF-8. 49 std::string msg; 50 if (!android::base::WideToUTF8(msgbuf, &msg)) { 51 return android::base::StringPrintf( 52 "Error %lu while converting message for error %lu from UTF-16 to UTF-8", 53 GetLastError(), error_code); 54 } 55 56 // Messages returned by the system end with line breaks. 57 msg = android::base::Trim(msg); 58 59 // There are many Windows error messages compared to POSIX, so include the 60 // numeric error code for easier, quicker, accurate identification. Use 61 // decimal instead of hex because there are decimal ranges like 10000-11999 62 // for Winsock. 63 android::base::StringAppendF(&msg, " (%lu)", error_code); 64 return msg; 65 } 66 67 } // namespace base 68 } // namespace android 69
