Reapply 91184 with fixes and an addition to the testcase to cover the problem

[oota-llvm.git] / lib / System / DynamicLibrary.cpp

diff --git a/lib/System/DynamicLibrary.cpp b/lib/System/DynamicLibrary.cpp
index a21f16ab327e71e45f68a4eb1cf35b8f882476c9..7eb9f5f3ef8e1439679f1647341723483d237310 100644 (file)
--- a/lib/System/DynamicLibrary.cpp
+++ b/lib/System/DynamicLibrary.cpp
@@ -9,35 +9,42 @@
 //
 //  This header file implements the operating system DynamicLibrary concept.
 //
+// FIXME: This file leaks the ExplicitSymbols and OpenedHandles vector, and is
+// not thread safe!
+//
 //===----------------------------------------------------------------------===//
 
 #include "llvm/System/DynamicLibrary.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 *> g_symbols;
+static std::map<std::string, void*> *ExplicitSymbols = 0;
+
+static struct ExplicitSymbolsDeleter {
+  ~ExplicitSymbolsDeleter() {
+    if (ExplicitSymbols)
+      delete ExplicitSymbols;
+  }
+} Dummy;
 
 void llvm::sys::DynamicLibrary::AddSymbol(const char* symbolName,
                                           void *symbolValue) {
-  g_symbols[symbolName] = symbolValue;
+  if (ExplicitSymbols == 0)
+    ExplicitSymbols = new std::map<std::string, void*>();
+  (*ExplicitSymbols)[symbolName] = symbolValue;
 }
 
-// It is not possible to use ltdl.c on VC++ builds as the terms of its LGPL
-// license and special exception would cause all of LLVM to be placed under
-// the LGPL.  This is because the exception applies only when libtool is
-// used, and obviously libtool is not used with Visual Studio.  An entirely
-// separate implementation is provided in win32/DynamicLibrary.cpp.
-
 #ifdef LLVM_ON_WIN32
 
 #include "Win32/DynamicLibrary.inc"
 
 #else
 
-#include "ltdl.h"
-#include <cassert>
+#include <dlfcn.h>
 using namespace llvm;
 using namespace llvm::sys;
 
@@ -46,97 +53,43 @@ using namespace llvm::sys;
 //===          independent code.
 //===----------------------------------------------------------------------===//
 
-static inline void check_ltdl_initialization() {
-  static bool did_initialize_ltdl = false;
-  if (!did_initialize_ltdl) {
-    int Err = lt_dlinit();
-    Err = Err; // Silence warning.
-    assert(0 == Err && "Can't init the ltdl library");
-    did_initialize_ltdl = true;
-  }
-}
-
-static std::vector<lt_dlhandle> OpenedHandles;
-
-DynamicLibrary::DynamicLibrary() : handle(0) {
-  check_ltdl_initialization();
-
-  lt_dlhandle a_handle = lt_dlopen(0);
-
-  assert(a_handle && "Can't open program as dynamic library");
-
-  handle = a_handle;
-  OpenedHandles.push_back(a_handle);
-}
-
-/*
-DynamicLibrary::DynamicLibrary(const char*filename) : handle(0) {
-  check_ltdl_initialization();
-
-  lt_dlhandle a_handle = lt_dlopen(filename);
-
-  if (a_handle == 0)
-    a_handle = lt_dlopenext(filename);
-
-  if (a_handle == 0)
-    throw std::string("Can't open :") + filename + ": " + lt_dlerror();
+static std::vector<void *> *OpenedHandles = 0;
 
-  handle = a_handle;
-  OpenedHandles.push_back(a_handle);
-}
-*/
-
-DynamicLibrary::~DynamicLibrary() {
-  lt_dlhandle a_handle = (lt_dlhandle) handle;
-  if (a_handle) {
-    lt_dlclose(a_handle);
-
-    for (std::vector<lt_dlhandle>::iterator I = OpenedHandles.begin(),
-         E = OpenedHandles.end(); I != E; ++I) {
-      if (*I == a_handle) {
-        // Note: don't use the swap/pop_back trick here. Order is important.
-        OpenedHandles.erase(I);
-        return;
-      }
-    }
-  }
-}
 
 bool DynamicLibrary::LoadLibraryPermanently(const char *Filename,
                                             std::string *ErrMsg) {
-  check_ltdl_initialization();
-  lt_dlhandle a_handle = lt_dlopen(Filename);
-
-  if (a_handle == 0)
-    a_handle = lt_dlopenext(Filename);
-
-  if (a_handle == 0) {
-    if (ErrMsg)
-      *ErrMsg = std::string("Can't open :") +
-          (Filename ? Filename : "<current process>") + ": " + lt_dlerror();
+  void *H = dlopen(Filename, RTLD_LAZY|RTLD_GLOBAL);
+  if (H == 0) {
+    if (ErrMsg) *ErrMsg = dlerror();
     return true;
   }
-
-  lt_dlmakeresident(a_handle);
-
-  OpenedHandles.push_back(a_handle);
+  if (OpenedHandles == 0)
+    OpenedHandles = new std::vector<void *>();
+  OpenedHandles->push_back(H);
   return false;
 }
 
 void* DynamicLibrary::SearchForAddressOfSymbol(const char* symbolName) {
-  check_ltdl_initialization();
-
   // First check symbols added via AddSymbol().
-  std::map<std::string, void *>::iterator I = g_symbols.find(symbolName);
-  if (I != g_symbols.end())
-    return I->second;
+  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;
+  }
 
   // Now search the libraries.
-  for (std::vector<lt_dlhandle>::iterator I = OpenedHandles.begin(),
-       E = OpenedHandles.end(); I != E; ++I) {
-    lt_ptr ptr = lt_dlsym(*I, symbolName);
-    if (ptr)
-      return ptr;
+  if (OpenedHandles) {
+    for (std::vector<void *>::iterator I = OpenedHandles->begin(),
+         E = OpenedHandles->end(); I != E; ++I) {
+      //lt_ptr ptr = lt_dlsym(*I, symbolName);
+      void *ptr = dlsym(*I, symbolName);
+      if (ptr) {
+        return ptr;
+      }
+    }
   }
 
 #define EXPLICIT_SYMBOL(SYM) \
@@ -170,6 +123,7 @@ void* DynamicLibrary::SearchForAddressOfSymbol(const char* symbolName) {
 #ifdef __CYGWIN__
   {
     EXPLICIT_SYMBOL(_alloca);
+    EXPLICIT_SYMBOL(__main);
   }
 #endif
 
@@ -208,11 +162,4 @@ void* DynamicLibrary::SearchForAddressOfSymbol(const char* symbolName) {
   return 0;
 }
 
-void *DynamicLibrary::GetAddressOfSymbol(const char *symbolName) {
-  assert(handle != 0 && "Invalid DynamicLibrary handle");
-  return lt_dlsym((lt_dlhandle) handle, symbolName);
-}
-
 #endif // LLVM_ON_WIN32
-
-DEFINING_FILE_FOR(SystemDynamicLibrary)