xnu-792.17.14.tar.gz

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

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The 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,
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 */
#include <IOKit/IOLib.h>
#include <mach/kmod.h>
#include <libkern/c++/OSDictionary.h>

#include <libsa/kext.h>
#include <libsa/catalogue.h>
#include <libsa/malloc.h>

#include "kld_patch.h"

/*****
 * 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;


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() {

    malloc_init();

    kmod_load_function = &load_kernel_extension;

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

    kernelLinkerPresent = 1;
}

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

    kld_file_cleanup_all_resources();

   /* Dump all device-tree entries for boot drivers, and all
    * info on startup extensions. The IOCatalogue will now
    * get personalities from kextd.
    */
    clearStartupExtensionsAndLoaderInfo();

   /* Free all temporary malloc memory.
    */
    malloc_reset();
}