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src/dyldInitialization.cpp dyld-46.16 dyld-360.18
--- dyld/dyld-46.16/src/dyldInitialization.cpp
+++ dyld/dyld-360.18/src/dyldInitialization.cpp
@@ -1,6 +1,6 @@
 /* -*- mode: C++; c-basic-offset: 4; tab-width: 4 -*-
  *
- * Copyright (c) 2004-2005 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2004-2008 Apple Inc. All rights reserved.
  *
  * @APPLE_LICENSE_HEADER_START@
  * 
@@ -22,28 +22,39 @@
  * @APPLE_LICENSE_HEADER_END@
  */
 
+#define __STDC_LIMIT_MACROS
+#include <stdint.h>
 #include <stddef.h>
 #include <string.h>
+#include <stdlib.h>
+#include <Availability.h>
 #include <mach/mach.h>
 #include <mach-o/loader.h>
 #include <mach-o/ldsyms.h>
 #include <mach-o/reloc.h>
-#if __ppc__ || __ppc64__
-	#include <mach-o/ppc/reloc.h>
-#endif
 #if __x86_64__
 	#include <mach-o/x86_64/reloc.h>
 #endif
 #include "dyld.h"
+#include "dyldSyscallInterface.h"
+
+// from dyld_gdb.cpp 
+extern void addImagesToAllImages(uint32_t infoCount, const dyld_image_info info[]);
+extern void syncProcessInfo();
+
+#ifndef MH_PIE
+	#define MH_PIE 0x200000 
+#endif
+
+// currently dyld has no initializers, but if some come back, set this to non-zero
+#define DYLD_INITIALIZER_SUPPORT  0
 
 #if __LP64__
-	#define macho_header			mach_header_64
 	#define LC_SEGMENT_COMMAND		LC_SEGMENT_64
 	#define macho_segment_command	segment_command_64
 	#define macho_section			section_64
 	#define RELOC_SIZE				3
 #else
-	#define macho_header			mach_header
 	#define LC_SEGMENT_COMMAND		LC_SEGMENT
 	#define macho_segment_command	segment_command
 	#define macho_section			section
@@ -56,6 +67,12 @@
 	#define POINTER_RELOC GENERIC_RELOC_VANILLA
 #endif
 
+
+#if TARGET_IPHONE_SIMULATOR
+const dyld::SyscallHelpers* gSyscallHelpers = NULL;
+#endif
+
+
 //
 //  Code to bootstrap dyld into a runnable state
 //
@@ -64,7 +81,13 @@
 namespace dyldbootstrap {
 
 
+
+#if DYLD_INITIALIZER_SUPPORT
+
 typedef void (*Initializer)(int argc, const char* argv[], const char* envp[], const char* apple[]);
+
+extern const Initializer  inits_start  __asm("section$start$__DATA$__mod_init_func");
+extern const Initializer  inits_end    __asm("section$end$__DATA$__mod_init_func");
 
 //
 // For a regular executable, the crt code calls dyld to run the executables initializers.
@@ -74,33 +97,33 @@
 //
 static void runDyldInitializers(const struct macho_header* mh, intptr_t slide, int argc, const char* argv[], const char* envp[], const char* apple[])
 {
+	for (const Initializer* p = &inits_start; p < &inits_end; ++p) {
+		(*p)(argc, argv, envp, apple);
+	}
+}
+#endif // DYLD_INITIALIZER_SUPPORT
+
+
+//
+//  The kernel may have slid a Position Independent Executable
+//
+static uintptr_t slideOfMainExecutable(const struct macho_header* mh)
+{
 	const uint32_t cmd_count = mh->ncmds;
 	const struct load_command* const cmds = (struct load_command*)(((char*)mh)+sizeof(macho_header));
 	const struct load_command* cmd = cmds;
 	for (uint32_t i = 0; i < cmd_count; ++i) {
-		switch (cmd->cmd) {
-			case LC_SEGMENT_COMMAND:
-				{
-					const struct macho_segment_command* seg = (struct macho_segment_command*)cmd;
-					const struct macho_section* const sectionsStart = (struct macho_section*)((char*)seg + sizeof(struct macho_segment_command));
-					const struct macho_section* const sectionsEnd = &sectionsStart[seg->nsects];
-					for (const struct macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
-						const uint8_t type = sect->flags & SECTION_TYPE;
-						if ( type == S_MOD_INIT_FUNC_POINTERS ){
-							Initializer* inits = (Initializer*)(sect->addr + slide);
-							const uint32_t count = sect->size / sizeof(uintptr_t);
-							for (uint32_t i=0; i < count; ++i) {
-								Initializer func = inits[i];
-								func(argc, argv, envp, apple);
-							}
-						}
-					}
-				}
-				break;
+		if ( cmd->cmd == LC_SEGMENT_COMMAND ) {
+			const struct macho_segment_command* segCmd = (struct macho_segment_command*)cmd;
+			if ( strcmp(segCmd->segname, "__TEXT") == 0 ) {
+				return (uintptr_t)mh - segCmd->vmaddr;
+			}
 		}
 		cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
 	}
-}
+	return 0;
+}
+
 
 //
 // If the kernel does not load dyld at its preferred address, we need to apply 
@@ -131,7 +154,7 @@
 						const uint8_t type = sect->flags & SECTION_TYPE;
 						if ( type == S_NON_LAZY_SYMBOL_POINTERS ) {
 							// rebase non-lazy pointers (which all point internal to dyld, since dyld uses no shared libraries)
-							const uint32_t pointerCount = sect->size / sizeof(uintptr_t);
+							const uint32_t pointerCount = (uint32_t)(sect->size / sizeof(uintptr_t));
 							uintptr_t* const symbolPointers = (uintptr_t*)(sect->addr + slide);
 							for (uint32_t j=0; j < pointerCount; ++j) {
 								symbolPointers[j] += slide;
@@ -160,10 +183,6 @@
 	const relocation_info* const relocsStart = (struct relocation_info*)(linkEditSeg->vmaddr + slide + dynamicSymbolTable->locreloff - linkEditSeg->fileoff);
 	const relocation_info* const relocsEnd = &relocsStart[dynamicSymbolTable->nlocrel];
 	for (const relocation_info* reloc=relocsStart; reloc < relocsEnd; ++reloc) {
-	#if __ppc__ || __ppc64__ || __i36__
-		if ( (reloc->r_address & R_SCATTERED) != 0 )
-			throw "scattered relocation in dyld";
-	#endif
 		if ( reloc->r_length != RELOC_SIZE ) 
 			throw "relocation in dyld has wrong size";
 
@@ -176,60 +195,27 @@
 }
 
 
-//
-// For some reason the kernel loads dyld with __TEXT and __LINKEDIT writable
-// rdar://problem/3702311 
-//
-static void segmentProtectDyld(const struct macho_header* mh, intptr_t slide)
-{
-	const uint32_t cmd_count = mh->ncmds;
-	const struct load_command* const cmds = (struct load_command*)(((char*)mh)+sizeof(macho_header));
-	const struct load_command* cmd = cmds;
-	for (uint32_t i = 0; i < cmd_count; ++i) {
-		switch (cmd->cmd) {
-			case LC_SEGMENT_COMMAND:
-				{
-					const struct macho_segment_command* seg = (struct macho_segment_command*)cmd;
-					vm_address_t addr = seg->vmaddr + slide;
-					vm_size_t size = seg->vmsize;
-					const bool setCurrentPermissions = false;
-					vm_protect(mach_task_self(), addr, size, setCurrentPermissions, seg->initprot);
-					//fprintf(stderr, "dyld: segment %s, 0x%08X -> 0x%08X, set to %d\n", seg->segname, addr, addr+size-1, seg->initprot);
-				}
-				break;
-		}
-		cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
-	}
-	
-}
-
-extern "C" void dyld_exceptions_init(const struct macho_header*, uintptr_t slide); // in dyldExceptions.cpp
 extern "C" void mach_init();
+extern "C" void __guard_setup(const char* apple[]);
+
 
 //
 //  This is code to bootstrap dyld.  This work in normally done for a program by dyld and crt.
 //  In dyld we have to do this manually.
 //
-uintptr_t start(const struct mach_header* appsMachHeader, int argc, const char* argv[], intptr_t slide)
-{
-	// _mh_dylinker_header is magic symbol defined by static linker (ld), see <mach-o/ldsyms.h>
-	const struct macho_header* dyldsMachHeader =  (const struct macho_header*)(((char*)&_mh_dylinker_header)+slide);
-	
+uintptr_t start(const struct macho_header* appsMachHeader, int argc, const char* argv[], 
+				intptr_t slide, const struct macho_header* dyldsMachHeader,
+				uintptr_t* startGlue)
+{
 	// if kernel had to slide dyld, we need to fix up load sensitive locations
 	// we have to do this before using any global variables
 	if ( slide != 0 ) {
 		rebaseDyld(dyldsMachHeader, slide);
 	}
-	
-	// enable C++ exceptions to work inside dyld
-	dyld_exceptions_init(dyldsMachHeader, slide);
-	
+
 	// allow dyld to use mach messaging
 	mach_init();
 
-	// set protection on segments (has to be done after mach_init)
-	segmentProtectDyld(dyldsMachHeader, slide);
-	
 	// kernel sets up env pointer to be just past end of agv array
 	const char** envp = &argv[argc+1];
 	
@@ -238,14 +224,55 @@
 	while(*apple != NULL) { ++apple; }
 	++apple;
 
+	// set up random value for stack canary
+	__guard_setup(apple);
+
+#if DYLD_INITIALIZER_SUPPORT
 	// run all C++ initializers inside dyld
 	runDyldInitializers(dyldsMachHeader, slide, argc, argv, envp, apple);
+#endif
+
+	// now that we are done bootstrapping dyld, call dyld's main
+	uintptr_t appsSlide = slideOfMainExecutable(appsMachHeader);
+	return dyld::_main(appsMachHeader, appsSlide, argc, argv, envp, apple, startGlue);
+}
+
+
+#if TARGET_IPHONE_SIMULATOR
+
+extern "C" uintptr_t start_sim(int argc, const char* argv[], const char* envp[], const char* apple[],
+							const macho_header* mainExecutableMH, const macho_header* dyldMH, uintptr_t dyldSlide,
+							const dyld::SyscallHelpers*, uintptr_t* startGlue);
+					
+					
+uintptr_t start_sim(int argc, const char* argv[], const char* envp[], const char* apple[],
+					const macho_header* mainExecutableMH, const macho_header* dyldMH, uintptr_t dyldSlide,
+					const dyld::SyscallHelpers* sc, uintptr_t* startGlue)
+{
+	// if simulator dyld loaded slid, it needs to rebase itself
+	// we have to do this before using any global variables
+	if ( dyldSlide != 0 ) {
+		rebaseDyld(dyldMH, dyldSlide);
+	}
+
+	// save table of syscall pointers
+	gSyscallHelpers = sc;
 	
+	// allow dyld to use mach messaging
+	mach_init();
+
+	// set up random value for stack canary
+	__guard_setup(apple);
+
+	// setup gProcessInfo to point to host dyld's struct
+	dyld::gProcessInfo = (struct dyld_all_image_infos*)(sc->getProcessInfo());
+	syncProcessInfo();
+
 	// now that we are done bootstrapping dyld, call dyld's main
-	return dyld::_main(appsMachHeader, argc, argv, envp, apple);
-}
-
-
+	uintptr_t appsSlide = slideOfMainExecutable(mainExecutableMH);
+	return dyld::_main(mainExecutableMH, appsSlide, argc, argv, envp, apple, startGlue);
+}
+#endif
 
 
 } // end of namespace