webrtc/talk/base/latebindingsymboltable.h
2013-10-07 23:32:02 +00:00

87 lines
3.1 KiB
C++

/*
* 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 <string.h>
#include "talk/base/common.h"
namespace talk_base {
#ifdef POSIX
typedef void *DllHandle;
#else
#error Not implemented for this platform
#endif
// This is the base class for "symbol table" classes to simplify the dynamic
// loading of symbols from DLLs. Currently the implementation only supports
// Linux and OS X, and pure C symbols (or extern "C" symbols that wrap C++
// functions). Sub-classes for specific DLLs are generated via the "supermacro"
// files latebindingsymboltable.h.def and latebindingsymboltable.cc.def. See
// talk/sound/pulseaudiosymboltable.(h|cc) for an example.
class LateBindingSymbolTable {
public:
struct TableInfo {
const char *dll_name;
int num_symbols;
// Array of size num_symbols.
const char *const *symbol_names;
};
LateBindingSymbolTable(const TableInfo *info, void **table);
~LateBindingSymbolTable();
bool IsLoaded() const;
// Loads the DLL and the symbol table. Returns true iff the DLL and symbol
// table loaded successfully.
bool Load();
// Like load, but allows overriding the dll path for when the dll path is
// dynamic.
bool LoadFromPath(const char *dll_path);
void Unload();
// Gets the raw OS handle to the DLL. Be careful what you do with it.
DllHandle GetDllHandle() const { return handle_; }
private:
void ClearSymbols();
const TableInfo *info_;
void **table_;
DllHandle handle_;
bool undefined_symbols_;
DISALLOW_COPY_AND_ASSIGN(LateBindingSymbolTable);
};
} // namespace talk_base
#endif // TALK_BASE_LATEBINDINGSYMBOLTABLE_H_