1*d4514f0bSApple OSS Distributions /* 2*d4514f0bSApple OSS Distributions * Copyright (c) 2000,2008-2012 Apple Inc. All rights reserved. 3*d4514f0bSApple OSS Distributions * 4*d4514f0bSApple OSS Distributions * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ 5*d4514f0bSApple OSS Distributions * 6*d4514f0bSApple OSS Distributions * This file contains Original Code and/or Modifications of Original Code 7*d4514f0bSApple OSS Distributions * as defined in and that are subject to the Apple Public Source License 8*d4514f0bSApple OSS Distributions * Version 2.0 (the 'License'). You may not use this file except in 9*d4514f0bSApple OSS Distributions * compliance with the License. The rights granted to you under the License 10*d4514f0bSApple OSS Distributions * may not be used to create, or enable the creation or redistribution of, 11*d4514f0bSApple OSS Distributions * unlawful or unlicensed copies of an Apple operating system, or to 12*d4514f0bSApple OSS Distributions * circumvent, violate, or enable the circumvention or violation of, any 13*d4514f0bSApple OSS Distributions * terms of an Apple operating system software license agreement. 14*d4514f0bSApple OSS Distributions * 15*d4514f0bSApple OSS Distributions * Please obtain a copy of the License at 16*d4514f0bSApple OSS Distributions * http://www.opensource.apple.com/apsl/ and read it before using this file. 17*d4514f0bSApple OSS Distributions * 18*d4514f0bSApple OSS Distributions * The Original Code and all software distributed under the License are 19*d4514f0bSApple OSS Distributions * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 20*d4514f0bSApple OSS Distributions * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 21*d4514f0bSApple OSS Distributions * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 22*d4514f0bSApple OSS Distributions * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 23*d4514f0bSApple OSS Distributions * Please see the License for the specific language governing rights and 24*d4514f0bSApple OSS Distributions * limitations under the License. 25*d4514f0bSApple OSS Distributions * 26*d4514f0bSApple OSS Distributions * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ 27*d4514f0bSApple OSS Distributions */ 28*d4514f0bSApple OSS Distributions /* 29*d4514f0bSApple 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*d4514f0bSApple OSS Distributions * 31*d4514f0bSApple 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*d4514f0bSApple OSS Distributions * KernelModule.bproj/kmod.make 33*d4514f0bSApple OSS Distributions * KernelModule.bproj/CreateKModInfo.perl 34*d4514f0bSApple OSS Distributions * KernelModule.bproj/kmodc++/pure.c 35*d4514f0bSApple OSS Distributions * KernelModule.bproj/kmodc++/cplus_start.c 36*d4514f0bSApple OSS Distributions * KernelModule.bproj/kmodc++/cplus_start.c 37*d4514f0bSApple OSS Distributions * KernelModule.bproj/kmodc/c_start.c 38*d4514f0bSApple OSS Distributions * KernelModule.bproj/kmodc/c_stop.c 39*d4514f0bSApple OSS Distributions * 40*d4514f0bSApple 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*d4514f0bSApple OSS Distributions * 42*d4514f0bSApple OSS Distributions * The linkline must look like this. 43*d4514f0bSApple OSS Distributions *.o -lkmodc++ kmod_info.o -lkmod 44*d4514f0bSApple OSS Distributions */ 45