1*42e22086SApple OSS Distributions /* 2*42e22086SApple OSS Distributions * Copyright (c) 2000,2008-2012 Apple Inc. All rights reserved. 3*42e22086SApple OSS Distributions * 4*42e22086SApple OSS Distributions * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ 5*42e22086SApple OSS Distributions * 6*42e22086SApple OSS Distributions * This file contains Original Code and/or Modifications of Original Code 7*42e22086SApple OSS Distributions * as defined in and that are subject to the Apple Public Source License 8*42e22086SApple OSS Distributions * Version 2.0 (the 'License'). You may not use this file except in 9*42e22086SApple OSS Distributions * compliance with the License. The rights granted to you under the License 10*42e22086SApple OSS Distributions * may not be used to create, or enable the creation or redistribution of, 11*42e22086SApple OSS Distributions * unlawful or unlicensed copies of an Apple operating system, or to 12*42e22086SApple OSS Distributions * circumvent, violate, or enable the circumvention or violation of, any 13*42e22086SApple OSS Distributions * terms of an Apple operating system software license agreement. 14*42e22086SApple OSS Distributions * 15*42e22086SApple OSS Distributions * Please obtain a copy of the License at 16*42e22086SApple OSS Distributions * http://www.opensource.apple.com/apsl/ and read it before using this file. 17*42e22086SApple OSS Distributions * 18*42e22086SApple OSS Distributions * The Original Code and all software distributed under the License are 19*42e22086SApple OSS Distributions * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 20*42e22086SApple OSS Distributions * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 21*42e22086SApple OSS Distributions * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 22*42e22086SApple OSS Distributions * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 23*42e22086SApple OSS Distributions * Please see the License for the specific language governing rights and 24*42e22086SApple OSS Distributions * limitations under the License. 25*42e22086SApple OSS Distributions * 26*42e22086SApple OSS Distributions * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ 27*42e22086SApple OSS Distributions */ 28*42e22086SApple OSS Distributions /* 29*42e22086SApple OSS Distributions * Subtle combination of files and libraries make up the C++ runtime system for kernel modules. We are dependant on the KernelModule kmod.make and CreateKModInfo.perl scripts to be exactly instep with both this library module and the libkmod module as well. 30*42e22086SApple OSS Distributions * 31*42e22086SApple OSS Distributions * If you do any maintenance on any of the following files make sure great care is taken to keep them in Sync. 32*42e22086SApple OSS Distributions * KernelModule.bproj/kmod.make 33*42e22086SApple OSS Distributions * KernelModule.bproj/CreateKModInfo.perl 34*42e22086SApple OSS Distributions * KernelModule.bproj/kmodc++/pure.c 35*42e22086SApple OSS Distributions * KernelModule.bproj/kmodc++/cplus_start.c 36*42e22086SApple OSS Distributions * KernelModule.bproj/kmodc++/cplus_start.c 37*42e22086SApple OSS Distributions * KernelModule.bproj/kmodc/c_start.c 38*42e22086SApple OSS Distributions * KernelModule.bproj/kmodc/c_stop.c 39*42e22086SApple OSS Distributions * 40*42e22086SApple OSS Distributions * The trick is that the linkline links all of the developers modules. If any static constructors are used .constructors_used will be left as an undefined symbol. This symbol is exported by the cplus_start.c routine which automatically brings in the appropriate C++ _start routine. However the actual _start symbol is only required by the kmod_info structure that is created and initialized by the CreateKModInfo.perl script. If no C++ was used the _start will be an undefined symbol that is finally satisfied by the c_start module in the kmod library. 41*42e22086SApple OSS Distributions * 42*42e22086SApple OSS Distributions * The linkline must look like this. 43*42e22086SApple OSS Distributions *.o -lkmodc++ kmod_info.o -lkmod 44*42e22086SApple OSS Distributions */ 45