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src/dyldInitialization.cpp dyld-46.16 dyld-195.6
--- dyld/dyld-46.16/src/dyldInitialization.cpp
+++ dyld/dyld-195.6/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@
  * 
@@ -22,8 +22,11 @@
  * @APPLE_LICENSE_HEADER_END@
  */
 
+#define __STDC_LIMIT_MACROS
+#include <stdint.h>
 #include <stddef.h>
 #include <string.h>
+#include <stdlib.h>
 #include <mach/mach.h>
 #include <mach-o/loader.h>
 #include <mach-o/ldsyms.h>
@@ -36,14 +39,17 @@
 #endif
 #include "dyld.h"
 
+#ifndef MH_PIE
+	#define MH_PIE 0x200000 
+#endif
+
+
 #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
@@ -55,6 +61,10 @@
 #else
 	#define POINTER_RELOC GENERIC_RELOC_VANILLA
 #endif
+
+// from dyld.cpp
+namespace dyld { extern bool isRosetta(); };
+
 
 //
 //  Code to bootstrap dyld into a runnable state
@@ -102,6 +112,28 @@
 	}
 }
 
+
+//
+//  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) {
+		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 
 // fixups to various initialized parts of the __DATA segment
@@ -176,60 +208,46 @@
 }
 
 
-//
-// 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();
 
 //
+// _pthread_keys is partitioned in a lower part that dyld will use; libSystem
+// will use the upper part.  We set __pthread_tsd_first to 1 as the start of
+// the lower part.  Libc will take #1 and c++ exceptions will take #2.  There
+// is one free key=3 left.
+//
+extern "C" {
+	extern int __pthread_tsd_first;
+	extern void _pthread_keys_init();
+}
+
+
+//
 //  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)
+{
 	// 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);
 	}
-	
+
+#if __IPHONE_OS_VERSION_MIN_REQUIRED		
+	// set pthread keys to dyld range
+	__pthread_tsd_first = 1;
+	_pthread_keys_init();
+#endif
+
 	// 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];
 	
@@ -240,9 +258,10 @@
 
 	// run all C++ initializers inside dyld
 	runDyldInitializers(dyldsMachHeader, slide, argc, argv, envp, apple);
-	
+		
 	// now that we are done bootstrapping dyld, call dyld's main
-	return dyld::_main(appsMachHeader, argc, argv, envp, apple);
+	uintptr_t appsSlide = slideOfMainExecutable(appsMachHeader);
+	return dyld::_main(appsMachHeader, appsSlide, argc, argv, envp, apple);
 }