1*0f4c859eSApple OSS Distributions /* 2*0f4c859eSApple OSS Distributions * Copyright (c) 2000,2008-2012 Apple Inc. All rights reserved. 3*0f4c859eSApple OSS Distributions * 4*0f4c859eSApple OSS Distributions * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ 5*0f4c859eSApple OSS Distributions * 6*0f4c859eSApple OSS Distributions * This file contains Original Code and/or Modifications of Original Code 7*0f4c859eSApple OSS Distributions * as defined in and that are subject to the Apple Public Source License 8*0f4c859eSApple OSS Distributions * Version 2.0 (the 'License'). You may not use this file except in 9*0f4c859eSApple OSS Distributions * compliance with the License. The rights granted to you under the License 10*0f4c859eSApple OSS Distributions * may not be used to create, or enable the creation or redistribution of, 11*0f4c859eSApple OSS Distributions * unlawful or unlicensed copies of an Apple operating system, or to 12*0f4c859eSApple OSS Distributions * circumvent, violate, or enable the circumvention or violation of, any 13*0f4c859eSApple OSS Distributions * terms of an Apple operating system software license agreement. 14*0f4c859eSApple OSS Distributions * 15*0f4c859eSApple OSS Distributions * Please obtain a copy of the License at 16*0f4c859eSApple OSS Distributions * http://www.opensource.apple.com/apsl/ and read it before using this file. 17*0f4c859eSApple OSS Distributions * 18*0f4c859eSApple OSS Distributions * The Original Code and all software distributed under the License are 19*0f4c859eSApple OSS Distributions * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 20*0f4c859eSApple OSS Distributions * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 21*0f4c859eSApple OSS Distributions * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 22*0f4c859eSApple OSS Distributions * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 23*0f4c859eSApple OSS Distributions * Please see the License for the specific language governing rights and 24*0f4c859eSApple OSS Distributions * limitations under the License. 25*0f4c859eSApple OSS Distributions * 26*0f4c859eSApple OSS Distributions * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ 27*0f4c859eSApple OSS Distributions */ 28*0f4c859eSApple OSS Distributions /* 29*0f4c859eSApple 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*0f4c859eSApple OSS Distributions * 31*0f4c859eSApple 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*0f4c859eSApple OSS Distributions * KernelModule.bproj/kmod.make 33*0f4c859eSApple OSS Distributions * KernelModule.bproj/CreateKModInfo.perl 34*0f4c859eSApple OSS Distributions * KernelModule.bproj/kmodc++/pure.c 35*0f4c859eSApple OSS Distributions * KernelModule.bproj/kmodc++/cplus_start.c 36*0f4c859eSApple OSS Distributions * KernelModule.bproj/kmodc++/cplus_start.c 37*0f4c859eSApple OSS Distributions * KernelModule.bproj/kmodc/c_start.c 38*0f4c859eSApple OSS Distributions * KernelModule.bproj/kmodc/c_stop.c 39*0f4c859eSApple OSS Distributions * 40*0f4c859eSApple 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*0f4c859eSApple OSS Distributions * 42*0f4c859eSApple OSS Distributions * The linkline must look like this. 43*0f4c859eSApple OSS Distributions *.o -lkmodc++ kmod_info.o -lkmod 44*0f4c859eSApple OSS Distributions */ 45