1 /* 2 * libjingle 3 * Copyright 2012, Google Inc. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright notice, 9 * this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright notice, 11 * this list of conditions and the following disclaimer in the documentation 12 * and/or other materials provided with the distribution. 13 * 3. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 17 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 18 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO 19 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 20 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 22 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 25 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 // This file is a supermacro 29 // (see http://wanderinghorse.net/computing/papers/supermacros_cpp.html) to 30 // expand a declaration of a late-binding symbol table class. 31 // 32 // Arguments: 33 // LATE_BINDING_SYMBOL_TABLE_CLASS_NAME: Name of the class to generate. 34 // LATE_BINDING_SYMBOL_TABLE_SYMBOLS_LIST: List of symbols to load from the DLL, 35 // as an X-Macro list (see http://www.drdobbs.com/blogs/cpp/228700289). 36 // 37 // From a .h file, include the header(s) for the DLL to late-bind and the 38 // latebindingsymboltable.h header, and then call this supermacro (optionally 39 // from inside the namespace for the class to generate, if any). Example: 40 // 41 // #include <headerfordll.h> 42 // 43 // #include "talk/base/latebindingsymboltable.h" 44 // 45 // namespace foo { 46 // 47 // #define MY_CLASS_NAME DesiredClassName 48 // #define MY_SYMBOLS_LIST X(acos) X(sin) X(tan) 49 // 50 // #define LATE_BINDING_SYMBOL_TABLE_CLASS_NAME MY_CLASS_NAME 51 // #define LATE_BINDING_SYMBOL_TABLE_SYMBOLS_LIST MY_SYMBOLS_LIST 52 // #include "talk/base/latebindingsymboltable.h.def" 53 // 54 // } 55 56 #ifndef TALK_BASE_LATEBINDINGSYMBOLTABLE_H_ 57 #error You must first include latebindingsymboltable.h 58 #endif 59 60 #ifndef LATE_BINDING_SYMBOL_TABLE_CLASS_NAME 61 #error You must define LATE_BINDING_SYMBOL_TABLE_CLASS_NAME 62 #endif 63 64 #ifndef LATE_BINDING_SYMBOL_TABLE_SYMBOLS_LIST 65 #error You must define LATE_BINDING_SYMBOL_TABLE_SYMBOLS_LIST 66 #endif 67 68 class LATE_BINDING_SYMBOL_TABLE_CLASS_NAME : 69 public ::talk_base::LateBindingSymbolTable { 70 public: 71 LATE_BINDING_SYMBOL_TABLE_CLASS_NAME(); 72 ~LATE_BINDING_SYMBOL_TABLE_CLASS_NAME(); 73 74 #define X(sym) \ 75 typeof(&::sym) sym() const { \ 76 ASSERT(::talk_base::LateBindingSymbolTable::IsLoaded()); \ 77 return reinterpret_cast<typeof(&::sym)>(table_[SYMBOL_TABLE_INDEX_##sym]); \ 78 } 79 LATE_BINDING_SYMBOL_TABLE_SYMBOLS_LIST 80 #undef X 81 82 private: 83 enum { 84 #define X(sym) \ 85 SYMBOL_TABLE_INDEX_##sym, 86 LATE_BINDING_SYMBOL_TABLE_SYMBOLS_LIST 87 #undef X 88 SYMBOL_TABLE_SIZE 89 }; 90 91 static const ::talk_base::LateBindingSymbolTable::TableInfo kTableInfo; 92 93 void *table_[SYMBOL_TABLE_SIZE]; 94 95 DISALLOW_COPY_AND_ASSIGN(LATE_BINDING_SYMBOL_TABLE_CLASS_NAME); 96 }; 97 98 #undef LATE_BINDING_SYMBOL_TABLE_CLASS_NAME 99 #undef LATE_BINDING_SYMBOL_TABLE_SYMBOLS_LIST 100
