| //===- Win32/DynamicLibrary.cpp - Win32 DL Implementation -------*- C++ -*-===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file provides the Win32 specific implementation of DynamicLibrary. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/Support/ConvertUTF.h" |
| #include "llvm/Support/Windows/WindowsSupport.h" |
| #include "llvm/Support/raw_ostream.h" |
| |
| #include <psapi.h> |
| |
| //===----------------------------------------------------------------------===// |
| //=== WARNING: Implementation here must contain only Win32 specific code |
| //=== and must not be UNIX code. |
| //===----------------------------------------------------------------------===// |
| |
| DynamicLibrary::HandleSet::~HandleSet() { |
| for (void *Handle : llvm::reverse(Handles)) |
| FreeLibrary(HMODULE(Handle)); |
| |
| // 'Process' should not be released on Windows. |
| assert((!Process || Process == this) && "Bad Handle"); |
| // llvm_shutdown called, Return to default |
| DynamicLibrary::SearchOrder = DynamicLibrary::SO_Linker; |
| } |
| |
| void *DynamicLibrary::HandleSet::DLOpen(const char *File, std::string *Err) { |
| // Create the instance and return it to be the *Process* handle |
| // simillar to dlopen(NULL, RTLD_LAZY|RTLD_GLOBAL) |
| if (!File) |
| return &getGlobals().OpenedHandles; |
| |
| SmallVector<wchar_t, MAX_PATH> FileUnicode; |
| if (std::error_code ec = windows::UTF8ToUTF16(File, FileUnicode)) { |
| SetLastError(ec.value()); |
| MakeErrMsg(Err, std::string(File) + ": Can't convert to UTF-16"); |
| return &DynamicLibrary::Invalid; |
| } |
| |
| HMODULE Handle = LoadLibraryW(FileUnicode.data()); |
| if (Handle == NULL) { |
| MakeErrMsg(Err, std::string(File) + ": Can't open"); |
| return &DynamicLibrary::Invalid; |
| } |
| |
| return reinterpret_cast<void *>(Handle); |
| } |
| |
| static DynamicLibrary::HandleSet *IsOpenedHandlesInstance(void *Handle) { |
| DynamicLibrary::HandleSet &Inst = getGlobals().OpenedHandles; |
| return Handle == &Inst ? &Inst : nullptr; |
| } |
| |
| void DynamicLibrary::HandleSet::DLClose(void *Handle) { |
| if (HandleSet *HS = IsOpenedHandlesInstance(Handle)) |
| HS->Process = nullptr; // Just drop the *Process* handle. |
| else |
| FreeLibrary((HMODULE)Handle); |
| } |
| |
| static bool GetProcessModules(HANDLE H, DWORD &Bytes, HMODULE *Data = nullptr) { |
| // EnumProcessModules will fail on Windows 64 while some versions of |
| // MingW-32 don't have EnumProcessModulesEx. |
| if ( |
| #ifdef _WIN64 |
| !EnumProcessModulesEx(H, Data, Bytes, &Bytes, LIST_MODULES_64BIT) |
| #else |
| !EnumProcessModules(H, Data, Bytes, &Bytes) |
| #endif |
| ) { |
| std::string Err; |
| if (MakeErrMsg(&Err, "EnumProcessModules failure")) |
| llvm::errs() << Err << "\n"; |
| return false; |
| } |
| return true; |
| } |
| |
| void *DynamicLibrary::HandleSet::DLSym(void *Handle, const char *Symbol) { |
| HandleSet *HS = IsOpenedHandlesInstance(Handle); |
| if (!HS) |
| return (void *)uintptr_t(GetProcAddress((HMODULE)Handle, Symbol)); |
| |
| // Could have done a dlclose on the *Process* handle |
| if (!HS->Process) |
| return nullptr; |
| |
| // Trials indicate EnumProcessModulesEx is consistantly faster than using |
| // EnumerateLoadedModules64 or CreateToolhelp32Snapshot. |
| // |
| // | Handles | DbgHelp.dll | CreateSnapshot | EnumProcessModulesEx |
| // |=========|=============|======================================== |
| // | 37 | 0.0000585 * | 0.0003031 | 0.0000152 |
| // | 1020 | 0.0026310 * | 0.0121598 | 0.0002683 |
| // | 2084 | 0.0149418 * | 0.0369936 | 0.0005610 |
| // |
| // * Not including the load time of Dbghelp.dll (~.005 sec) |
| // |
| // There's still a case to somehow cache the result of EnumProcessModulesEx |
| // across invocations, but the complication of doing that properly... |
| // Possibly using LdrRegisterDllNotification to invalidate the cache? |
| |
| DWORD Bytes = 0; |
| HMODULE Self = HMODULE(GetCurrentProcess()); |
| if (!GetProcessModules(Self, Bytes)) |
| return nullptr; |
| |
| // Get the most recent list in case any modules added/removed between calls |
| // to EnumProcessModulesEx that gets the amount of, then copies the HMODULES. |
| // MSDN is pretty clear that if the module list changes during the call to |
| // EnumProcessModulesEx the results should not be used. |
| std::vector<HMODULE> Handles; |
| do { |
| assert(Bytes && ((Bytes % sizeof(HMODULE)) == 0) && |
| "Should have at least one module and be aligned"); |
| Handles.resize(Bytes / sizeof(HMODULE)); |
| if (!GetProcessModules(Self, Bytes, Handles.data())) |
| return nullptr; |
| } while (Bytes != (Handles.size() * sizeof(HMODULE))); |
| |
| // Try EXE first, mirroring what dlsym(dlopen(NULL)) does. |
| if (FARPROC Ptr = GetProcAddress(HMODULE(Handles.front()), Symbol)) |
| return (void *)uintptr_t(Ptr); |
| |
| if (Handles.size() > 1) { |
| // This is different behaviour than what Posix dlsym(dlopen(NULL)) does. |
| // Doing that here is causing real problems for the JIT where msvc.dll |
| // and ucrt.dll can define the same symbols. The runtime linker will choose |
| // symbols from ucrt.dll first, but iterating NOT in reverse here would |
| // mean that the msvc.dll versions would be returned. |
| |
| for (auto I = Handles.rbegin(), E = Handles.rend() - 1; I != E; ++I) { |
| if (FARPROC Ptr = GetProcAddress(HMODULE(*I), Symbol)) |
| return (void *)uintptr_t(Ptr); |
| } |
| } |
| return nullptr; |
| } |
| |
| // Stack probing routines are in the support library (e.g. libgcc), but we don't |
| // have dynamic linking on windows. Provide a hook. |
| #define EXPLICIT_SYMBOL(SYM) \ |
| extern "C" { \ |
| extern void *SYM; \ |
| } |
| #define EXPLICIT_SYMBOL2(SYMFROM, SYMTO) EXPLICIT_SYMBOL(SYMTO) |
| |
| #ifdef _M_IX86 |
| // Win32 on x86 implements certain single-precision math functions as macros. |
| // These functions are not exported by the DLL, but will still be needed |
| // for symbol-resolution by the JIT loader. Therefore, this Support libray |
| // provides helper functions with the same implementation. |
| |
| #define INLINE_DEF_SYMBOL1(TYP, SYM) \ |
| extern "C" TYP inline_##SYM(TYP _X) { return SYM(_X); } |
| #define INLINE_DEF_SYMBOL2(TYP, SYM) \ |
| extern "C" TYP inline_##SYM(TYP _X, TYP _Y) { return SYM(_X, _Y); } |
| #endif |
| |
| #include "explicit_symbols.inc" |
| |
| #undef EXPLICIT_SYMBOL |
| #undef EXPLICIT_SYMBOL2 |
| #undef INLINE_DEF_SYMBOL1 |
| #undef INLINE_DEF_SYMBOL2 |
| |
| static void *DoSearch(const char *SymbolName) { |
| |
| #define EXPLICIT_SYMBOL(SYM) \ |
| if (!strcmp(SymbolName, #SYM)) \ |
| return (void *)&SYM; |
| #define EXPLICIT_SYMBOL2(SYMFROM, SYMTO) \ |
| if (!strcmp(SymbolName, #SYMFROM)) \ |
| return (void *)&SYMTO; |
| |
| #ifdef _M_IX86 |
| #define INLINE_DEF_SYMBOL1(TYP, SYM) \ |
| if (!strcmp(SymbolName, #SYM)) \ |
| return (void *)&inline_##SYM; |
| #define INLINE_DEF_SYMBOL2(TYP, SYM) INLINE_DEF_SYMBOL1(TYP, SYM) |
| #endif |
| |
| { |
| #include "explicit_symbols.inc" |
| } |
| |
| #undef EXPLICIT_SYMBOL |
| #undef EXPLICIT_SYMBOL2 |
| #undef INLINE_DEF_SYMBOL1 |
| #undef INLINE_DEF_SYMBOL2 |
| |
| return nullptr; |
| } |
