llvm-6502/lib/Support/DynamicLinker.cpp

96 lines
3.2 KiB
C++
Raw Normal View History

//===-- DynamicLinker.cpp - Implement DynamicLinker interface -------------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Lightweight interface to dynamic library linking and loading, and dynamic
// symbol lookup functionality, in whatever form the operating system
// provides it.
//
// Possible future extensions include support for the HPUX shl_load()
// interface, and the Mac OS X NSLinkModule() interface.
//
// Note that we assume that if dlopen() is available, then dlsym() is too.
//
//===----------------------------------------------------------------------===//
#include "Support/DynamicLinker.h"
#include "Config/dlfcn.h"
#include "Config/windows.h"
#include <cassert>
#include <vector>
using namespace llvm;
#if defined(HAVE_WINDOWS_H)
// getLoadedLibs - Keep track of the shared objects that are loaded into the
// process address space, as the windows GetProcAddress function does not
// automatically search an entire address space, it only searches a specific
// object.
static std::vector<HMODULE> &getLoadedLibHandles() {
static std::vector<HMODULE> *LoadedLibHandles = 0;
if (LoadedLibHandles == 0) {
LoadedLibHandles = new std::vector<HMODULE>();
if (HMODULE H = GetModuleHandle(NULL)) // JIT symbols
LoadedLibHandles->push_back(H);
if (HMODULE MH = GetModuleHandle("cygwin1.dll")) // Cygwin symbols OR
LoadedLibHandles->push_back(MH);
else if (HMODULE MH = GetModuleHandle("msvcr80.dll")) // VC++ symbols
LoadedLibHandles->push_back(MH);
}
return *LoadedLibHandles;
}
#endif
bool llvm::LinkDynamicObject(const char *filename, std::string *ErrorMessage) {
#if defined(HAVE_WINDOWS_H)
if (HMODULE Handle = LoadLibrary(filename)) {
// Allow GetProcAddress in this module
getLoadedLibHandles().push_back(Handle);
return false;
}
if (ErrorMessage) {
char Buffer[100];
// FIXME: This should use FormatMessage
sprintf(Buffer, "Windows error code %d\n", GetLastError());
*ErrorMessage = Buffer;
}
return true;
#elif defined (HAVE_DLOPEN)
if (dlopen (filename, RTLD_NOW | RTLD_GLOBAL) == 0) {
if (ErrorMessage) *ErrorMessage = dlerror ();
return true;
}
return false;
#else
assert (0 && "Dynamic object linking not implemented for this platform");
#endif
}
void *llvm::GetAddressOfSymbol(const char *symbolName) {
#if defined(HAVE_WINDOWS_H)
std::vector<HMODULE> &LH = getLoadedLibHandles();
for (unsigned i = 0, e = LH.size(); i != e; ++i)
if (void *Val = (void*)GetProcAddress(LH[i], symbolName))
return Val;
return 0;
#elif defined(HAVE_DLOPEN)
# ifdef RTLD_DEFAULT
return dlsym (RTLD_DEFAULT, symbolName);
# else
static void* CurHandle = dlopen(0, RTLD_LAZY);
return dlsym(CurHandle, symbolName);
# endif
#else
assert (0 && "Dynamic symbol lookup not implemented for this platform");
#endif
}
// soft, cushiony C++ interface.
void *llvm::GetAddressOfSymbol(const std::string &symbolName) {
return GetAddressOfSymbol(symbolName.c_str());
}