1 //===-- DynamicLinker.cpp - Implement DynamicLinker interface -------------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // Lightweight interface to dynamic library linking and loading, and dynamic
11 // symbol lookup functionality, in whatever form the operating system
14 // Possible future extensions include support for the HPUX shl_load()
15 // interface, and the Mac OS X NSLinkModule() interface.
17 // Note that we assume that if dlopen() is available, then dlsym() is too.
19 //===----------------------------------------------------------------------===//
21 #include "llvm/Support/DynamicLinker.h"
22 #include "llvm/Config/dlfcn.h"
23 #include "llvm/Config/windows.h"
29 #if defined(HAVE_WINDOWS_H)
30 // getLoadedLibs - Keep track of the shared objects that are loaded into the
31 // process address space, as the windows GetProcAddress function does not
32 // automatically search an entire address space, it only searches a specific
34 static std::vector<HMODULE> &getLoadedLibHandles() {
35 static std::vector<HMODULE> *LoadedLibHandles = 0;
36 if (LoadedLibHandles == 0) {
37 LoadedLibHandles = new std::vector<HMODULE>();
38 if (HMODULE H = GetModuleHandle(NULL)) // JIT symbols
39 LoadedLibHandles->push_back(H);
40 if (HMODULE MH = GetModuleHandle("cygwin1.dll")) // Cygwin symbols OR
41 LoadedLibHandles->push_back(MH);
42 else if (HMODULE MH = GetModuleHandle("msvcr80.dll")) // VC++ symbols
43 LoadedLibHandles->push_back(MH);
45 return *LoadedLibHandles;
49 bool llvm::LinkDynamicObject(const char *filename, std::string *ErrorMessage) {
50 #if defined(HAVE_WINDOWS_H)
51 if (HMODULE Handle = LoadLibrary(filename)) {
52 // Allow GetProcAddress in this module
53 getLoadedLibHandles().push_back(Handle);
58 // FIXME: This should use FormatMessage
59 sprintf(Buffer, "Windows error code %d\n", GetLastError());
60 *ErrorMessage = Buffer;
63 #elif defined (HAVE_DLOPEN)
64 if (dlopen (filename, RTLD_NOW | RTLD_GLOBAL) == 0) {
65 if (ErrorMessage) *ErrorMessage = dlerror ();
70 assert (0 && "Dynamic object linking not implemented for this platform");
74 void *llvm::GetAddressOfSymbol(const char *symbolName) {
75 #if defined(HAVE_WINDOWS_H)
76 std::vector<HMODULE> &LH = getLoadedLibHandles();
77 for (unsigned i = 0, e = LH.size(); i != e; ++i)
78 if (void *Val = (void*)GetProcAddress(LH[i], symbolName))
81 #elif defined(HAVE_DLOPEN)
83 return dlsym (RTLD_DEFAULT, symbolName);
85 static void* CurHandle = dlopen(0, RTLD_LAZY);
86 return dlsym(CurHandle, symbolName);
89 assert (0 && "Dynamic symbol lookup not implemented for this platform");
93 // soft, cushiony C++ interface.
94 void *llvm::GetAddressOfSymbol(const std::string &symbolName) {
95 return GetAddressOfSymbol(symbolName.c_str());