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 #include "start_glue.h"
  33
  34 extern "C" void start();
  35
  36
  37 VIS_HIDDEN const char** appleParams;
  38
  39 extern bool gUseDyld3;
  40
  41 namespace dyld3 {
  42
  43
  44 AllImages::ProgramVars sVars;
  45 static void (*sChildForkFunction)();
  46
  47 static const char* leafName(const char* argv0)
  48 {
  49     if ( argv0 == nullptr )
  50        return "";
  51
  52     if ( const char* lastSlash = strrchr(argv0, '/') )
  53         return lastSlash+1;
  54     else
  55         return argv0;
  56 }
  57
  58 static void entry_setVars(const mach_header* mainMH, int argc, const char* argv[], const char* envp[], const char* apple[])
  59 {
  60     NXArgc       = argc;
  61     NXArgv       = argv;
  62     environ      = (char**)envp;
  63     appleParams  = apple;
  64     __progname   = leafName(argv[0]);
  65
  66     sVars.mh            = mainMH;
  67     sVars.NXArgcPtr     = &NXArgc;
  68     sVars.NXArgvPtr     = &NXArgv;
  69     sVars.environPtr    = (const char***)&environ;
  70     sVars.__prognamePtr = &__progname;
  71     gAllImages.setProgramVars(&sVars);
  72
  73     gUseDyld3 = true;
  74
  75     setLoggingFromEnvs(envp);
  76 }
  77
  78 static void entry_setHaltFunction(void (*func)(const char* message) __attribute__((noreturn)) )
  79 {
  80     setHaltFunction(func);
  81 }
  82
  83 static void entry_setLogFunction(void (*logFunction)(const char* format, va_list list))
  84 {
  85     setLoggingFunction(logFunction);
  86 }
  87
  88 static void entry_setOldAllImageInfo(dyld_all_image_infos* old)
  89 {
  90     gAllImages.setOldAllImageInfo(old);
  91 }
  92
  93 static void entry_setInitialImageList(const launch_cache::binary_format::Closure* closure,
  94                                 const void* dyldCacheLoadAddress, const char* dyldCachePath,
  95                                 const dyld3::launch_cache::DynArray<loader::ImageInfo>& initialImages,
  96                                 const mach_header* libSystemMH, const launch_cache::binary_format::Image* libSystemImage)
  97 {
  98     gAllImages.init(closure, dyldCacheLoadAddress, dyldCachePath, initialImages);
  99     gAllImages.applyInterposingToDyldCache(closure, initialImages);
 100
 101     const char* mainPath = _simple_getenv(appleParams, "executable_path");
 102     if ( (mainPath != nullptr) && (mainPath[0] == '/') )
 103         gAllImages.setMainPath(mainPath);
 104
 105     // ok to call before malloc is ready because 4 slots are reserved.
 106     gAllImages.setInitialGroups();
 107
 108     // run initializer for libSytem.B.dylib
 109     // this calls back into _dyld_initializer which calls gAllIimages.addImages()
 110     gAllImages.runLibSystemInitializer(libSystemMH, libSystemImage);
 111
 112     // now that malloc is available, parse DYLD_ env vars
 113     gPathOverrides.setEnvVars((const char**)environ);
 114 }
 115
 116 static void entry_runInitialzersBottomUp(const mach_header* mainExecutableImageLoadAddress)
 117 {
 118     gAllImages.runInitialzersBottomUp(mainExecutableImageLoadAddress);
 119     gAllImages.notifyMonitorMain();
 120 }
 121
 122 static void entry_setChildForkFunction(void (*func)() )
 123 {
 124     sChildForkFunction = func;
 125 }
 126
 127 typedef void (*StartFunc)();
 128
 129 const LibDyldEntryVector entryVectorForDyld = {
 130     LibDyldEntryVector::kCurrentVectorVersion,
 131     launch_cache::binary_format::kFormatVersion,
 132     &entry_setVars,
 133     &entry_setHaltFunction,
 134     &entry_setOldAllImageInfo,
 135     &entry_setInitialImageList,
 136     &entry_runInitialzersBottomUp,
 137     (StartFunc)address_of_start,
 138     &entry_setChildForkFunction,
 139     &entry_setLogFunction,
 140 };
 141
 142 VIS_HIDDEN void _dyld_fork_child()
 143 {
 144     (*sChildForkFunction)();
 145 }
 146
 147
 148 } // namespace dyld3
 149