/// It also allows for symbols to be defined which don't live in any library,
/// but rather the main program itself, useful on Windows where the main
/// executable cannot be searched.
+ ///
+ /// Note: there is currently no interface for temporarily loading a library,
+ /// or for unloading libraries when the LLVM library is unloaded.
class DynamicLibrary {
- DynamicLibrary(); // DO NOT IMPLEMENT
+ // Opaque data used to interface with OS-specific dynamic library handling.
+ void *Data;
+
+ explicit DynamicLibrary(void *data = 0) : Data(data) {}
public:
- /// This function allows a library to be loaded without instantiating a
- /// DynamicLibrary object. Consequently, it is marked as being permanent
- /// and will only be unloaded when the program terminates. This returns
- /// false on success or returns true and fills in *ErrMsg on failure.
- /// @brief Open a dynamic library permanently.
+ /// Returns true if the object refers to a valid library.
+ bool isValid() { return Data != 0; }
+
+ /// Searches through the library for the symbol \p symbolName. If it is
+ /// found, the address of that symbol is returned. If not, NULL is returned.
+ /// Note that NULL will also be returned if the library failed to load.
+ /// Use isValid() to distinguish these cases if it is important.
+ /// Note that this will \e not search symbols explicitly registered by
+ /// AddSymbol().
+ void *getAddressOfSymbol(const char *symbolName);
+
+ /// This function permanently loads the dynamic library at the given path.
+ /// The library will only be unloaded when the program terminates.
+ /// This returns a valid DynamicLibrary instance on success and an invalid
+ /// instance on failure (see isValid()). \p *errMsg will only be modified
+ /// if the library fails to load.
///
- /// NOTE: This function is not thread safe.
+ /// It is safe to call this function multiple times for the same library.
+ /// @brief Open a dynamic library permanently.
+ static DynamicLibrary getPermanentLibrary(const char *filename,
+ std::string *errMsg = 0);
+
+ /// 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.
///
- static bool LoadLibraryPermanently(const char *filename,
- std::string *ErrMsg = 0);
+ /// It is safe to call this function multiple times for the same library.
+ static bool LoadLibraryPermanently(const char *Filename,
+ std::string *ErrMsg = 0) {
+ return !getPermanentLibrary(Filename, ErrMsg).isValid();
+ }
/// This function will search through all previously loaded dynamic
- /// libraries for the symbol \p symbolName. If it is found, the addressof
+ /// libraries for the symbol \p symbolName. If it is found, the address of
/// that symbol is returned. If not, null is returned. Note that this will
- /// search permanently loaded libraries (LoadLibraryPermanently) as well
- /// as ephemerally loaded libraries (constructors).
+ /// search permanently loaded libraries (getPermanentLibrary()) as well
+ /// as explicitly registered symbols (AddSymbol()).
/// @throws std::string on error.
/// @brief Search through libraries for address of a symbol
- ///
- /// NOTE: This function is not thread safe.
- ///
static void *SearchForAddressOfSymbol(const char *symbolName);
/// @brief Convenience function for C++ophiles.
- ///
- /// NOTE: This function is not thread safe.
- ///
static void *SearchForAddressOfSymbol(const std::string &symbolName) {
return SearchForAddressOfSymbol(symbolName.c_str());
}
/// value \p symbolValue. These symbols are searched before any
/// libraries.
/// @brief Add searchable symbol/value pair.
- ///
- /// NOTE: This function is not thread safe.
- ///
- static void AddSymbol(const char *symbolName, void *symbolValue);
-
- /// @brief Convenience function for C++ophiles.
- ///
- /// NOTE: This function is not thread safe.
- ///
- static void AddSymbol(const std::string &symbolName, void *symbolValue) {
- AddSymbol(symbolName.c_str(), symbolValue);
- }
+ static void AddSymbol(StringRef symbolName, void *symbolValue);
};
} // End sys namespace
//
// This header file implements the operating system DynamicLibrary concept.
//
-// FIXME: This file leaks the ExplicitSymbols and OpenedHandles vector, and is
-// not thread safe!
+// FIXME: This file leaks ExplicitSymbols and OpenedHandles!
//
//===----------------------------------------------------------------------===//
+#include "llvm/ADT/StringMap.h"
+#include "llvm/ADT/DenseSet.h"
#include "llvm/Support/DynamicLibrary.h"
#include "llvm/Support/Mutex.h"
#include "llvm/Config/config.h"
#include <cstdio>
#include <cstring>
-#include <map>
-#include <vector>
// Collection of symbol name/value pairs to be searched prior to any libraries.
-static std::map<std::string, void*> *ExplicitSymbols = 0;
+static llvm::StringMap<void *> *ExplicitSymbols = 0;
namespace {
struct ExplicitSymbolsDeleter {
~ExplicitSymbolsDeleter() {
- if (ExplicitSymbols)
- delete ExplicitSymbols;
+ delete ExplicitSymbols;
}
};
static ExplicitSymbolsDeleter Dummy;
-void llvm::sys::DynamicLibrary::AddSymbol(const char* symbolName,
+
+static llvm::sys::SmartMutex<true>& getMutex() {
+ static llvm::sys::SmartMutex<true> HandlesMutex;
+ return HandlesMutex;
+}
+
+void llvm::sys::DynamicLibrary::AddSymbol(StringRef symbolName,
void *symbolValue) {
+ SmartScopedLock<true> lock(getMutex());
if (ExplicitSymbols == 0)
- ExplicitSymbols = new std::map<std::string, void*>();
+ ExplicitSymbols = new llvm::StringMap<void*>();
(*ExplicitSymbols)[symbolName] = symbolValue;
}
//=== independent code.
//===----------------------------------------------------------------------===//
-static std::vector<void *> *OpenedHandles = 0;
-
-
-static SmartMutex<true>& getMutex() {
- static SmartMutex<true> HandlesMutex;
- return HandlesMutex;
-}
-
+static DenseSet<void *> *OpenedHandles = 0;
-bool DynamicLibrary::LoadLibraryPermanently(const char *Filename,
- std::string *ErrMsg) {
- void *H = dlopen(Filename, RTLD_LAZY|RTLD_GLOBAL);
- if (H == 0) {
- if (ErrMsg) *ErrMsg = dlerror();
- return true;
+DynamicLibrary DynamicLibrary::getPermanentLibrary(const char *filename,
+ std::string *errMsg) {
+ void *handle = dlopen(filename, RTLD_LAZY|RTLD_GLOBAL);
+ if (handle == 0) {
+ if (errMsg) *errMsg = dlerror();
+ return DynamicLibrary();
}
+
#ifdef __CYGWIN__
// Cygwin searches symbols only in the main
// with the handle of dlopen(NULL, RTLD_GLOBAL).
- if (Filename == NULL)
- H = RTLD_DEFAULT;
+ if (filename == NULL)
+ handle = RTLD_DEFAULT;
#endif
- SmartScopedLock<true> Lock(getMutex());
+
+ SmartScopedLock<true> lock(getMutex());
if (OpenedHandles == 0)
- OpenedHandles = new std::vector<void *>();
- OpenedHandles->push_back(H);
- return false;
+ OpenedHandles = new DenseSet<void *>();
+
+ // If we've already loaded this library, dlclose() the handle in order to
+ // keep the internal refcount at +1.
+ if (!OpenedHandles->insert(handle).second)
+ dlclose(handle);
+
+ return DynamicLibrary(handle);
+}
+
+void *DynamicLibrary::getAddressOfSymbol(const char *symbolName) {
+ if (!isValid())
+ return NULL;
+ return dlsym(Data, symbolName);
}
+
#else
using namespace llvm;
using namespace llvm::sys;
-bool DynamicLibrary::LoadLibraryPermanently(const char *Filename,
- std::string *ErrMsg) {
- if (ErrMsg) *ErrMsg = "dlopen() not supported on this platform";
- return true;
+DynamicLibrary DynamicLibrary::getPermanentLibrary(const char *filename,
+ std::string *errMsg) {
+ if (errMsg) *errMsg = "dlopen() not supported on this platform";
+ return DynamicLibrary();
}
+
+void *DynamicLibrary::getAddressOfSymbol(const char *symbolName) {
+ return NULL;
+}
+
#endif
namespace llvm {
void *SearchForAddressOfSpecialSymbol(const char* symbolName);
}
-void* DynamicLibrary::SearchForAddressOfSymbol(const char* symbolName) {
+void* DynamicLibrary::SearchForAddressOfSymbol(const char *symbolName) {
+ SmartScopedLock<true> Lock(getMutex());
+
// First check symbols added via AddSymbol().
if (ExplicitSymbols) {
- std::map<std::string, void *>::iterator I =
- ExplicitSymbols->find(symbolName);
- std::map<std::string, void *>::iterator E = ExplicitSymbols->end();
+ StringMap<void *>::iterator i = ExplicitSymbols->find(symbolName);
- if (I != E)
- return I->second;
+ if (i != ExplicitSymbols->end())
+ return i->second;
}
#if HAVE_DLFCN_H
// Now search the libraries.
- SmartScopedLock<true> Lock(getMutex());
if (OpenedHandles) {
- for (std::vector<void *>::iterator I = OpenedHandles->begin(),
+ for (DenseSet<void *>::iterator I = OpenedHandles->begin(),
E = OpenedHandles->end(); I != E; ++I) {
//lt_ptr ptr = lt_dlsym(*I, symbolName);
void *ptr = dlsym(*I, symbolName);
//=== and must not be UNIX code.
//===----------------------------------------------------------------------===//
-static std::vector<HMODULE> OpenedHandles;
+static DenseSet<HMODULE> *OpenedHandles;
extern "C" {
#endif
stricmp(ModuleName, "msvcrt20") != 0 &&
stricmp(ModuleName, "msvcrt40") != 0) {
- OpenedHandles.push_back((HMODULE)ModuleBase);
+ OpenedHandles->push_back((HMODULE)ModuleBase);
}
return TRUE;
}
}
-bool DynamicLibrary::LoadLibraryPermanently(const char *filename,
- std::string *ErrMsg) {
- if (filename) {
- HMODULE a_handle = LoadLibrary(filename);
+DynamicLibrary DynamicLibrary::getPermanentLibrary(const char *filename,
+ std::string *errMsg) {
+ if (!filename) {
+ // When no file is specified, enumerate all DLLs and EXEs in the process.
+ SmartScopedLock<true> lock(getMutex());
+ if (OpenedHandles == 0)
+ OpenedHandles = new DenseSet<HMODULE>();
- if (a_handle == 0)
- return MakeErrMsg(ErrMsg, std::string(filename) + ": Can't open : ");
-
- OpenedHandles.push_back(a_handle);
- } else {
- // When no file is specified, enumerate all DLLs and EXEs in the
- // process.
EnumerateLoadedModules(GetCurrentProcess(), ELM_Callback, 0);
+ // Dummy library that represents "search all handles".
+ // This is mostly to ensure that the return value still shows up as "valid".
+ return DynamicLibrary(&OpenedHandles);
+ }
+
+ HMODULE a_handle = LoadLibrary(filename);
+
+ if (a_handle == 0) {
+ MakeErrMsg(ErrMsg, std::string(filename) + ": Can't open : ");
+ return DynamicLibrary();
}
- // Because we don't remember the handle, we will never free it; hence,
- // it is loaded permanently.
- return false;
+ SmartScopedLock<true> lock(getMutex());
+ if (OpenedHandles == 0)
+ OpenedHandles = new DenseSet<HMODULE>();
+
+ // 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)
+ FreeLibrary(a_handle);
+
+ return DynamicLibrary(a_handle);
}
// Stack probing routines are in the support library (e.g. libgcc), but we don't
#undef EXPLICIT_SYMBOL2
void* DynamicLibrary::SearchForAddressOfSymbol(const char* symbolName) {
+ SmartScopedLock<true> Lock(getMutex());
+
// First check symbols added via AddSymbol().
if (ExplicitSymbols) {
- std::map<std::string, void *>::iterator I =
- ExplicitSymbols->find(symbolName);
- std::map<std::string, void *>::iterator E = ExplicitSymbols->end();
- if (I != E)
- return I->second;
+ StringMap<void *>::iterator i = ExplicitSymbols->find(symbolName);
+
+ if (i != ExplicitSymbols->end())
+ return i->second;
}
// Now search the libraries.
- for (std::vector<HMODULE>::iterator I = OpenedHandles.begin(),
- E = OpenedHandles.end(); I != E; ++I) {
- FARPROC ptr = GetProcAddress((HMODULE)*I, symbolName);
- if (ptr) {
- return (void *)(intptr_t)ptr;
+ if (OpenedHandles) {
+ for (DenseSet<HMODULE>::iterator I = OpenedHandles->begin(),
+ E = OpenedHandles->end(); I != E; ++I) {
+ FARPROC ptr = GetProcAddress((HMODULE)*I, symbolName);
+ if (ptr) {
+ return (void *)(intptr_t)ptr;
+ }
}
}
return 0;
}
+
+void *DynamicLibrary::getAddressOfSymbol(const char *symbolName) {
+ if (!isValid())
+ return NULL;
+ if (Data == &OpenedHandles)
+ return SearchForAddressOfSymbol(symbolName);
+ return (void *)(intptr_t)GetProcAddress((HMODULE)Data, symbolName);
+}
+
+
}
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