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diff --git a/third_party/libjingle/source/talk/base/latebindingsymboltable.h b/third_party/libjingle/source/talk/base/latebindingsymboltable.h
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+/*
+ * libjingle
+ * Copyright 2004--2010, Google Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *  1. Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *  2. Redistributions in binary form must reproduce the above copyright notice,
+ *     this list of conditions and the following disclaimer in the documentation
+ *     and/or other materials provided with the distribution.
+ *  3. The name of the author may not be used to endorse or promote products
+ *     derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef TALK_BASE_LATEBINDINGSYMBOLTABLE_H_
+#define TALK_BASE_LATEBINDINGSYMBOLTABLE_H_
+
+#include <stddef.h>  // for NULL
+#include <string.h>
+
+#include "talk/base/common.h"
+#include "talk/base/logging.h"
+
+// This file provides macros for creating "symbol table" classes to simplify the
+// dynamic loading of symbols from DLLs. Currently the implementation only
+// supports Linux and pure C symbols.
+// See talk/sound/pulseaudiosymboltable.(h|cc) for an example.
+
+namespace talk_base {
+
+#ifdef LINUX
+typedef void *DllHandle;
+
+const DllHandle kInvalidDllHandle = NULL;
+#else
+#error Not implemented
+#endif
+
+// These are helpers for use only by the class below.
+DllHandle InternalLoadDll(const char dll_name[]);
+
+void InternalUnloadDll(DllHandle handle);
+
+bool InternalLoadSymbols(DllHandle handle,
+                         int num_symbols,
+                         const char *const symbol_names[],
+                         void *symbols[]);
+
+template <int SYMBOL_TABLE_SIZE,
+          const char kDllName[],
+          const char *const kSymbolNames[]>
+class LateBindingSymbolTable {
+ public:
+  LateBindingSymbolTable()
+      : handle_(kInvalidDllHandle),
+        undefined_symbols_(false) {
+    memset(symbols_, 0, sizeof(symbols_));
+  }
+
+  ~LateBindingSymbolTable() {
+    Unload();
+  }
+
+  static int NumSymbols() {
+    return SYMBOL_TABLE_SIZE;
+  }
+
+  // We do not use this, but we offer it for theoretical convenience.
+  static const char *GetSymbolName(int index) {
+    ASSERT(index < NumSymbols());
+    return kSymbolNames[index];
+  }
+
+  bool IsLoaded() const {
+    return handle_ != kInvalidDllHandle;
+  }
+
+  // Loads the DLL and the symbol table. Returns true iff the DLL and symbol
+  // table loaded successfully.
+  bool Load() {
+    if (IsLoaded()) {
+      return true;
+    }
+    if (undefined_symbols_) {
+      // We do not attempt to load again because repeated attempts are not
+      // likely to succeed and DLL loading is costly.
+      LOG(LS_ERROR) << "We know there are undefined symbols";
+      return false;
+    }
+    handle_ = InternalLoadDll(kDllName);
+    if (!IsLoaded()) {
+      return false;
+    }
+    if (!InternalLoadSymbols(handle_, NumSymbols(), kSymbolNames, symbols_)) {
+      undefined_symbols_ = true;
+      Unload();
+      return false;
+    }
+    return true;
+  }
+
+  void Unload() {
+    if (!IsLoaded()) {
+      return;
+    }
+    InternalUnloadDll(handle_);
+    handle_ = kInvalidDllHandle;
+    memset(symbols_, 0, sizeof(symbols_));
+  }
+
+  // Retrieves the given symbol. NOTE: Recommended to use LATESYM_GET below
+  // instead of this.
+  void *GetSymbol(int index) const {
+    ASSERT(IsLoaded());
+    ASSERT(index < NumSymbols());
+    return symbols_[index];
+  }
+
+ private:
+  DllHandle handle_;
+  bool undefined_symbols_;
+  void *symbols_[SYMBOL_TABLE_SIZE];
+
+  DISALLOW_COPY_AND_ASSIGN(LateBindingSymbolTable);
+};
+
+// This macro must be invoked in a header to declare a symbol table class.
+#define LATE_BINDING_SYMBOL_TABLE_DECLARE_BEGIN(ClassName) \
+enum {
+
+// This macro must be invoked in the header declaration once for each symbol
+// (recommended to use an X-Macro to avoid duplication).
+// This macro defines an enum with names built from the symbols, which
+// essentially creates a hash table in the compiler from symbol names to their
+// indices in the symbol table class.
+#define LATE_BINDING_SYMBOL_TABLE_DECLARE_ENTRY(ClassName, sym) \
+  ClassName##_SYMBOL_TABLE_INDEX_##sym,
+
+// This macro completes the header declaration.
+#define LATE_BINDING_SYMBOL_TABLE_DECLARE_END(ClassName) \
+  ClassName##_SYMBOL_TABLE_SIZE \
+}; \
+\
+extern const char ClassName##_kDllName[]; \
+extern const char *const \
+    ClassName##_kSymbolNames[ClassName##_SYMBOL_TABLE_SIZE]; \
+\
+typedef ::talk_base::LateBindingSymbolTable<ClassName##_SYMBOL_TABLE_SIZE, \
+                                            ClassName##_kDllName, \
+                                            ClassName##_kSymbolNames> \
+    ClassName;
+
+// This macro must be invoked in a .cc file to define a previously-declared
+// symbol table class.
+#define LATE_BINDING_SYMBOL_TABLE_DEFINE_BEGIN(ClassName, dllName) \
+const char ClassName##_kDllName[] = dllName; \
+const char *const ClassName##_kSymbolNames[ClassName##_SYMBOL_TABLE_SIZE] = {
+
+// This macro must be invoked in the .cc definition once for each symbol
+// (recommended to use an X-Macro to avoid duplication).
+// This would have to use the mangled name if we were to ever support C++
+// symbols.
+#define LATE_BINDING_SYMBOL_TABLE_DEFINE_ENTRY(ClassName, sym) \
+  #sym,
+
+#define LATE_BINDING_SYMBOL_TABLE_DEFINE_END(ClassName) \
+};
+
+// Index of a given symbol in the given symbol table class.
+#define LATESYM_INDEXOF(ClassName, sym) \
+  (ClassName##_SYMBOL_TABLE_INDEX_##sym)
+
+// Returns a reference to the given late-binded symbol, with the correct type.
+#define LATESYM_GET(ClassName, inst, sym) \
+  (*reinterpret_cast<typeof(&sym)>( \
+      (inst)->GetSymbol(LATESYM_INDEXOF(ClassName, sym))))
+
+}  // namespace talk_base
+
+#endif  // TALK_BASE_LATEBINDINGSYMBOLTABLE_H_