Orion Hodson | 3979966 | 2020-04-21 12:28:04 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2020 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 "DlHelp.h" |
| 18 | |
| 19 | #include <stdbool.h> |
| 20 | |
| 21 | #ifdef WIN32_LEAN_AND_MEAN |
| 22 | #include <stdio.h> |
| 23 | #include <windows.h> |
| 24 | #else |
| 25 | #include <dlfcn.h> |
| 26 | #endif |
| 27 | |
| 28 | DlLibrary DlOpenLibrary(const char* filename) { |
| 29 | #ifdef _WIN32 |
| 30 | return LoadLibrary(filename); |
| 31 | #else |
| 32 | // Load with RTLD_NODELETE in order to ensure that libart.so is not unmapped when it is closed. |
| 33 | // This is due to the fact that it is possible that some threads might have yet to finish |
| 34 | // exiting even after JNI_DeleteJavaVM returns, which can lead to segfaults if the library is |
| 35 | // unloaded. |
| 36 | return dlopen(filename, RTLD_NOW | RTLD_NODELETE); |
| 37 | #endif |
| 38 | } |
| 39 | |
| 40 | bool DlCloseLibrary(DlLibrary library) { |
| 41 | #ifdef _WIN32 |
| 42 | return (FreeLibrary(library) == TRUE); |
| 43 | #else |
| 44 | return (dlclose(library) == 0); |
| 45 | #endif |
| 46 | } |
| 47 | |
| 48 | DlSymbol DlGetSymbol(DlLibrary handle, const char* symbol) { |
| 49 | #ifdef _WIN32 |
| 50 | return (DlSymbol) GetProcAddress(handle, symbol); |
| 51 | #else |
| 52 | return dlsym(handle, symbol); |
| 53 | #endif |
| 54 | } |
| 55 | |
| 56 | const char* DlGetError() { |
| 57 | #ifdef _WIN32 |
| 58 | static char buffer[256]; |
| 59 | |
| 60 | DWORD cause = GetLastError(); |
| 61 | DWORD flags = FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS; |
| 62 | DWORD length = FormatMessageA(flags, NULL, cause, 0, buffer, sizeof(buffer), NULL); |
| 63 | if (length == 0) { |
| 64 | snprintf(buffer, sizeof(buffer), |
| 65 | "Error %lu while retrieving message for error %lu", |
| 66 | GetLastError(), cause); |
| 67 | length = strlen(buffer); |
| 68 | } |
| 69 | |
| 70 | // Trim trailing whitespace. |
| 71 | for (DWORD i = length - 1; i > 0; --i) { |
| 72 | if (!isspace(buffer[i])) { |
| 73 | break; |
| 74 | } |
| 75 | buffer[i] = '\0'; |
| 76 | } |
| 77 | |
| 78 | return buffer; |
| 79 | #else |
| 80 | return dlerror(); |
| 81 | #endif |
| 82 | } |