summaryrefslogtreecommitdiffstats
path: root/contrib/llvm/lib/Support/DynamicLibrary.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'contrib/llvm/lib/Support/DynamicLibrary.cpp')
-rw-r--r--contrib/llvm/lib/Support/DynamicLibrary.cpp189
1 files changed, 189 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Support/DynamicLibrary.cpp b/contrib/llvm/lib/Support/DynamicLibrary.cpp
new file mode 100644
index 0000000..fb02c07
--- /dev/null
+++ b/contrib/llvm/lib/Support/DynamicLibrary.cpp
@@ -0,0 +1,189 @@
+//===-- DynamicLibrary.cpp - Runtime link/load libraries --------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This header file implements the operating system DynamicLibrary concept.
+//
+// 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>
+
+// Collection of symbol name/value pairs to be searched prior to any libraries.
+static llvm::StringMap<void *> *ExplicitSymbols = 0;
+
+namespace {
+
+struct ExplicitSymbolsDeleter {
+ ~ExplicitSymbolsDeleter() {
+ delete ExplicitSymbols;
+ }
+};
+
+}
+
+static ExplicitSymbolsDeleter Dummy;
+
+
+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 llvm::StringMap<void*>();
+ (*ExplicitSymbols)[symbolName] = symbolValue;
+}
+
+char llvm::sys::DynamicLibrary::Invalid = 0;
+
+#ifdef LLVM_ON_WIN32
+
+#include "Windows/DynamicLibrary.inc"
+
+#else
+
+#if HAVE_DLFCN_H
+#include <dlfcn.h>
+using namespace llvm;
+using namespace llvm::sys;
+
+//===----------------------------------------------------------------------===//
+//=== WARNING: Implementation here must contain only TRULY operating system
+//=== independent code.
+//===----------------------------------------------------------------------===//
+
+static DenseSet<void *> *OpenedHandles = 0;
+
+DynamicLibrary DynamicLibrary::getPermanentLibrary(const char *filename,
+ std::string *errMsg) {
+ SmartScopedLock<true> lock(getMutex());
+
+ 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)
+ handle = RTLD_DEFAULT;
+#endif
+
+ if (OpenedHandles == 0)
+ 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;
+
+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) {
+ SmartScopedLock<true> Lock(getMutex());
+
+ // First check symbols added via AddSymbol().
+ if (ExplicitSymbols) {
+ StringMap<void *>::iterator i = ExplicitSymbols->find(symbolName);
+
+ if (i != ExplicitSymbols->end())
+ return i->second;
+ }
+
+#if HAVE_DLFCN_H
+ // Now search the libraries.
+ if (OpenedHandles) {
+ 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);
+ if (ptr) {
+ return ptr;
+ }
+ }
+ }
+#endif
+
+ if (void *Result = llvm::SearchForAddressOfSpecialSymbol(symbolName))
+ return Result;
+
+// This macro returns the address of a well-known, explicit symbol
+#define EXPLICIT_SYMBOL(SYM) \
+ if (!strcmp(symbolName, #SYM)) return &SYM
+
+// On linux we have a weird situation. The stderr/out/in symbols are both
+// macros and global variables because of standards requirements. So, we
+// boldly use the EXPLICIT_SYMBOL macro without checking for a #define first.
+#if defined(__linux__)
+ {
+ EXPLICIT_SYMBOL(stderr);
+ EXPLICIT_SYMBOL(stdout);
+ EXPLICIT_SYMBOL(stdin);
+ }
+#else
+ // For everything else, we want to check to make sure the symbol isn't defined
+ // as a macro before using EXPLICIT_SYMBOL.
+ {
+#ifndef stdin
+ EXPLICIT_SYMBOL(stdin);
+#endif
+#ifndef stdout
+ EXPLICIT_SYMBOL(stdout);
+#endif
+#ifndef stderr
+ EXPLICIT_SYMBOL(stderr);
+#endif
+ }
+#endif
+#undef EXPLICIT_SYMBOL
+
+ return 0;
+}
+
+#endif // LLVM_ON_WIN32
OpenPOWER on IntegriCloud