xnu-124.13.tar.gz

[apple/xnu.git] / libsa / bootstrap.cpp

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
#include <IOKit/IOLib.h>
#include <mach/kmod.h>
#include <libkern/c++/OSDictionary.h>

#include <libsa/kmod.h>
#include <libsa/catalogue.h>
extern "C" {
#include <libsa/malloc.h>
};

extern "C" {
/*****
 * This function is used by IOCatalogue to load a kernel
 * extension. libsa initially sets it to be a function
 * that uses libkld to load and link the extension from
 * within the kernel. Once the root filesystem is up,
 * this gets switch to the kmod_load_extension() function,
 * which merely queues the extension for loading by the
 * kmodload utility.
 */
extern kern_return_t (*kmod_load_function)(char *extension_name);
extern bool (*record_startup_extensions_function)(void);
extern bool (*add_from_mkext_function)(OSData * mkext);
extern void (*remove_startup_extension_function)(const char * name);

/****
 * IOCatalogue uses this variable to make a few decisions
 * about loading and matching drivers.
 */
extern int kernelLinkerPresent;

extern IOLock * kld_lock;
};


class KLDBootstrap {
public:
    KLDBootstrap();
    ~KLDBootstrap();
};


static KLDBootstrap bootstrap_obj;


/* The constructor creates a lock and puts entries into a dispatch
 * table for functions used to record and load kmods.
 */
KLDBootstrap::KLDBootstrap() {

    kld_lock = IOLockAlloc();
    IOLockLock(kld_lock);

    kmod_load_function = &load_kernel_extension;

    record_startup_extensions_function = &recordStartupExtensions;
    add_from_mkext_function = &addExtensionsFromArchive;
    remove_startup_extension_function = &removeStartupExtension;

    kernelLinkerPresent = 1;

    IOLockUnlock(kld_lock);
}

/* The destructor frees all wired memory regions held
 * by libsa's malloc package and disposes of the lock.
 */
KLDBootstrap::~KLDBootstrap() {

    OSDictionary * startupExtensions;

    IOLockLock(kld_lock);

    malloc_reset();

    startupExtensions = getStartupExtensions();
    if (startupExtensions) startupExtensions->release();

    IOLockUnlock(kld_lock);
    IOLockFree(kld_lock);

}