dyld3/libdyldEntryVector.cpp

   1 /*
   2  * Copyright (c) 2017 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 #include <stdarg.h>
  25
  26 #include "dyld_priv.h"
  27 #include "libdyldEntryVector.h"
  28 #include "AllImages.h"
  29 #include "Logging.h"
  30 #include "PathOverrides.h"
  31 #include "LaunchCacheFormat.h"
  32
  33 extern "C" void start();
  34
  35
  36 VIS_HIDDEN const char** appleParams;
  37
  38 extern bool gUseDyld3;
  39
  40 namespace dyld3 {
  41
  42
  43 AllImages::ProgramVars sVars;
  44 static void (*sChildForkFunction)();
  45
  46 static const char* leafName(const char* argv0)
  47 {
  48     if ( argv0 == nullptr )
  49        return "";
  50
  51     if ( const char* lastSlash = strrchr(argv0, '/') )
  52         return lastSlash+1;
  53     else
  54         return argv0;
  55 }
  56
  57 static void entry_setVars(const mach_header* mainMH, int argc, const char* argv[], const char* envp[], const char* apple[])
  58 {
  59     NXArgc       = argc;
  60     NXArgv       = argv;
  61     environ      = (char**)envp;
  62     appleParams  = apple;
  63     __progname   = leafName(argv[0]);
  64
  65     sVars.mh            = mainMH;
  66     sVars.NXArgcPtr     = &NXArgc;
  67     sVars.NXArgvPtr     = &NXArgv;
  68     sVars.environPtr    = (const char***)&environ;
  69     sVars.__prognamePtr = &__progname;
  70     gAllImages.setProgramVars(&sVars);
  71
  72     gUseDyld3 = true;
  73
  74     setLoggingFromEnvs(envp);
  75 }
  76
  77 static void entry_setHaltFunction(void (*func)(const char* message) __attribute__((noreturn)) )
  78 {
  79     setHaltFunction(func);
  80 }
  81
  82 static void entry_setLogFunction(void (*logFunction)(const char* format, va_list list))
  83 {
  84     setLoggingFunction(logFunction);
  85 }
  86
  87 static void entry_setOldAllImageInfo(dyld_all_image_infos* old)
  88 {
  89     gAllImages.setOldAllImageInfo(old);
  90 }
  91
  92 static void entry_setInitialImageList(const launch_cache::binary_format::Closure* closure,
  93                                 const void* dyldCacheLoadAddress, const char* dyldCachePath,
  94                                 const dyld3::launch_cache::DynArray<loader::ImageInfo>& initialImages,
  95                                 const mach_header* libSystemMH, const launch_cache::binary_format::Image* libSystemImage)
  96 {
  97     gAllImages.init(closure, dyldCacheLoadAddress, dyldCachePath, initialImages);
  98     gAllImages.applyInterposingToDyldCache(closure, initialImages);
  99
 100     const char* mainPath = _simple_getenv(appleParams, "executable_path");
 101     if ( (mainPath != nullptr) && (mainPath[0] == '/') )
 102         gAllImages.setMainPath(mainPath);
 103
 104     // ok to call before malloc is ready because 4 slots are reserved.
 105     gAllImages.setInitialGroups();
 106
 107     // run initializer for libSytem.B.dylib
 108     // this calls back into _dyld_initializer which calls gAllIimages.addImages()
 109     gAllImages.runLibSystemInitializer(libSystemMH, libSystemImage);
 110
 111     // now that malloc is available, parse DYLD_ env vars
 112     gPathOverrides.setEnvVars((const char**)environ);
 113 }
 114
 115 static void entry_runInitialzersBottomUp(const mach_header* mainExecutableImageLoadAddress)
 116 {
 117     gAllImages.runInitialzersBottomUp(mainExecutableImageLoadAddress);
 118     gAllImages.notifyMonitorMain();
 119 }
 120
 121 static void entry_setChildForkFunction(void (*func)() )
 122 {
 123     sChildForkFunction = func;
 124 }
 125
 126 const LibDyldEntryVector entryVectorForDyld = {
 127     LibDyldEntryVector::kCurrentVectorVersion,
 128     launch_cache::binary_format::kFormatVersion,
 129     &entry_setVars,
 130     &entry_setHaltFunction,
 131     &entry_setOldAllImageInfo,
 132     &entry_setInitialImageList,
 133     &entry_runInitialzersBottomUp,
 134     &start,
 135     &entry_setChildForkFunction,
 136     &entry_setLogFunction,
 137 };
 138
 139 VIS_HIDDEN void _dyld_fork_child()
 140 {
 141     (*sChildForkFunction)();
 142 }
 143
 144
 145 } // namespace dyld3
 146