From: Vassil Vassilev Date: Tue, 28 Feb 2017 07:11:59 +0000 (+0000) Subject: Allow externally dlopen-ed libraries to be registered as permanent libraries. X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=5951ab5b7a4c1e776a2b5b76b422d14f1ff880e3;p=llvm Allow externally dlopen-ed libraries to be registered as permanent libraries. This is also useful in cases when llvm is in a shared library. First we dlopen the llvm shared library and then we register it as a permanent library in order to keep the JIT and other services working. Patch reviewed by Vedant Kumar (D29955)! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296442 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/include/llvm/Support/DynamicLibrary.h b/include/llvm/Support/DynamicLibrary.h index a7d22212dbd..ea49a16dd02 100644 --- a/include/llvm/Support/DynamicLibrary.h +++ b/include/llvm/Support/DynamicLibrary.h @@ -14,6 +14,8 @@ #ifndef LLVM_SUPPORT_DYNAMICLIBRARY_H #define LLVM_SUPPORT_DYNAMICLIBRARY_H +#include "llvm/Support/Mutex.h" + #include namespace llvm { @@ -43,6 +45,11 @@ namespace sys { // Opaque data used to interface with OS-specific dynamic library handling. void *Data; + // Adds a opened library handle to the list of OpenedHandles. + static DynamicLibrary addPermanentLibraryWithLock(void *handle, + sys::SmartScopedLock &, + bool isMainExec); + public: explicit DynamicLibrary(void *data = &Invalid) : Data(data) {} @@ -68,6 +75,14 @@ namespace sys { static DynamicLibrary getPermanentLibrary(const char *filename, std::string *errMsg = nullptr); + /// Registers an externally loaded library. The library will be unloaded + /// when the program terminates. + /// + /// It is safe to call this function multiple times for the same library. + /// + /// \returns An empty \p DynamicLibrary on failure. + static DynamicLibrary addPermanentLibrary(void *handle); + /// This function permanently loads the dynamic library at the given path. /// Use this instead of getPermanentLibrary() when you won't need to get /// symbols from the library itself. diff --git a/lib/Support/DynamicLibrary.cpp b/lib/Support/DynamicLibrary.cpp index 74d94d33d5a..d3983fb4437 100644 --- a/lib/Support/DynamicLibrary.cpp +++ b/lib/Support/DynamicLibrary.cpp @@ -68,10 +68,34 @@ DynamicLibrary DynamicLibrary::getPermanentLibrary(const char *filename, handle = RTLD_DEFAULT; #endif + DynamicLibrary dyLib = addPermanentLibraryWithLock(handle, lock, !filename); + // If we've already loaded this library, dlclose() the handle in order to // keep the internal refcount at +1. - if (!OpenedHandles->insert(handle).second) + if (!dyLib.isValid()) { + if (errMsg) + *errMsg = (filename) ? std::string(filename) : std::string() + + ": Library already loaded"; dlclose(handle); + } + + return dyLib; +} + +DynamicLibrary DynamicLibrary::addPermanentLibrary(void *handle) { + SmartScopedLock lock(*SymbolsMutex); + return addPermanentLibraryWithLock(handle, lock, false); +} + +DynamicLibrary DynamicLibrary::addPermanentLibraryWithLock(void *handle, + sys::SmartScopedLock &, + bool isMainExec) { + // If we've already loaded this library, tell the caller. + // FIXME: Note that multiple requests for adding the main executable is not + // considered as an error. If we don't want to treat the main executable as a + // special case we need to do a cleanup in the MCJIT tests and API. + if (!OpenedHandles->insert(handle).second && !isMainExec) + return DynamicLibrary(); return DynamicLibrary(handle); } diff --git a/lib/Support/Windows/DynamicLibrary.inc b/lib/Support/Windows/DynamicLibrary.inc index 87dde46de3c..264754942ba 100644 --- a/lib/Support/Windows/DynamicLibrary.inc +++ b/lib/Support/Windows/DynamicLibrary.inc @@ -9,8 +9,6 @@ // // This file provides the Win32 specific implementation of DynamicLibrary. // -// FIXME: This file leaks OpenedHandles! -// //===----------------------------------------------------------------------===// #include "WindowsSupport.h" @@ -35,7 +33,7 @@ using namespace sys; typedef BOOL (WINAPI *fpEnumerateLoadedModules)(HANDLE,PENUMLOADED_MODULES_CALLBACK64,PVOID); static fpEnumerateLoadedModules fEnumerateLoadedModules; -static DenseSet *OpenedHandles; +static llvm::ManagedStatic > OpenedHandles; static bool loadDebugHelp(void) { HMODULE hLib = ::LoadLibraryW(L"Dbghelp.dll"); @@ -59,9 +57,6 @@ DynamicLibrary DynamicLibrary::getPermanentLibrary(const char *filename, if (!filename) { // When no file is specified, enumerate all DLLs and EXEs in the process. - if (OpenedHandles == 0) - OpenedHandles = new DenseSet(); - if (!fEnumerateLoadedModules) { if (!loadDebugHelp()) { assert(false && "These APIs should always be available"); @@ -81,7 +76,7 @@ DynamicLibrary DynamicLibrary::getPermanentLibrary(const char *filename, MakeErrMsg(errMsg, std::string(filename) + ": Can't convert to UTF-16"); return DynamicLibrary(); } - + HMODULE a_handle = LoadLibraryW(filenameUnicode.data()); if (a_handle == 0) { @@ -89,15 +84,33 @@ DynamicLibrary DynamicLibrary::getPermanentLibrary(const char *filename, return DynamicLibrary(); } - if (OpenedHandles == 0) - OpenedHandles = new DenseSet(); - + DynamicLibrary dyLib = addPermanentLibraryWithLock(a_handle, lock, !filename); // If we've already loaded this library, FreeLibrary() the handle in order to // keep the internal refcount at +1. - if (!OpenedHandles->insert(a_handle).second) + if (!dyLib.isValid()) { + MakeErrMsg(errMsg, std::string(filename) + ": Already loaded"); FreeLibrary(a_handle); + } + + return dyLib; +} + +DynamicLibrary DynamicLibrary::addPermanentLibrary(void *handle) { + SmartScopedLock lock(*SymbolsMutex); + return addPermanentLibraryWithLock(handle, lock); +} + +DynamicLibrary DynamicLibrary::addPermanentLibraryWithLock(void *handle, + sys::SmartScopedLock &, + bool isMainExec) { + // If we've already loaded this library, tell the caller. + // FIXME: Note that multiple requests for adding the main executable is not + // considered as an error. If we don't want to treat the main executable as a + // special case we need to do a cleanup in the MCJIT tests and API. + if (!OpenedHandles->insert((const HMODULE)handle).second && !isMainExec) + return DynamicLibrary(); - return DynamicLibrary(a_handle); + return DynamicLibrary((HMODULE)handle); } // Stack probing routines are in the support library (e.g. libgcc), but we don't