Loading...
src/ImageLoader.cpp dyld-195.5 dyld-360.19
--- dyld/dyld-195.5/src/ImageLoader.cpp
+++ dyld/dyld-360.19/src/ImageLoader.cpp
@@ -24,6 +24,7 @@
 
 #define __STDC_LIMIT_MACROS
 #include <stdint.h>
+#include <stdlib.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <mach/mach.h>
@@ -64,46 +65,35 @@
 
 
 ImageLoader::ImageLoader(const char* path, unsigned int libCount)
-	: fPath(path), fDevice(0), fInode(0), fLastModified(0), 
-	fPathHash(0), fDlopenReferenceCount(0), fStaticReferenceCount(0),
-	fDynamicReferenceCount(0), fDynamicReferences(NULL), fInitializerRecursiveLock(NULL), 
+	: fPath(path), fRealPath(NULL), fDevice(0), fInode(0), fLastModified(0), 
+	fPathHash(0), fDlopenReferenceCount(0), fInitializerRecursiveLock(NULL), 
 	fDepth(0), fLoadOrder(fgLoadOrdinal++), fState(0), fLibraryCount(libCount), 
 	fAllLibraryChecksumsAndLoadAddressesMatch(false), fLeaveMapped(false), fNeverUnload(false),
 	fHideSymbols(false), fMatchByInstallName(false),
 	fInterposed(false), fRegisteredDOF(false), fAllLazyPointersBound(false), 
     fBeingRemoved(false), fAddFuncNotified(false),
-	fPathOwnedByImage(false), fWeakSymbolsBound(false)
+	fPathOwnedByImage(false), fIsReferencedDownward(false), 
+	fWeakSymbolsBound(false)
 {
 	if ( fPath != NULL )
 		fPathHash = hash(fPath);
+	if ( libCount > 512 )
+		dyld::throwf("too many dependent dylibs in %s", path);
 }
 
 
 void ImageLoader::deleteImage(ImageLoader* image)
 {
-	// this cannot be done in destructor because libImage() is implemented
-	// in a subclass
-	DependentLibraryInfo libraryInfos[image->libraryCount()]; 
-	image->doGetDependentLibraries(libraryInfos);
-	for(unsigned int i=0; i < image->libraryCount(); ++i) {
-		ImageLoader* lib = image->libImage(i);
-		if ( (lib != NULL) && ! libraryInfos[i].upward )
-			lib->fStaticReferenceCount--;
-	}
 	delete image;
 }
 
 
 ImageLoader::~ImageLoader()
 {
+	if ( fRealPath != NULL ) 
+		delete [] fRealPath;
 	if ( fPathOwnedByImage && (fPath != NULL) ) 
 		delete [] fPath;
-	if ( fDynamicReferences != NULL ) {
-		for (std::vector<const ImageLoader*>::iterator it = fDynamicReferences->begin(); it != fDynamicReferences->end(); ++it ) {
-			const_cast<ImageLoader*>(*it)->fDynamicReferenceCount--;
-		}
-		delete fDynamicReferences;
-	}
 }
 
 void ImageLoader::setFileInfo(dev_t device, ino_t inode, time_t modDate)
@@ -117,27 +107,6 @@
 {
 	fState = dyld_image_state_mapped;
 	context.notifySingle(dyld_image_state_mapped, this);  // note: can throw exception
-}
-
-void ImageLoader::addDynamicReference(const ImageLoader* target)
-{
-	bool alreadyInVector = false;
-	if ( fDynamicReferences == NULL ) {
-		fDynamicReferences = new std::vector<const ImageLoader*>();
-	}
-	else {
-		for (std::vector<const ImageLoader*>::iterator it = fDynamicReferences->begin(); it != fDynamicReferences->end(); ++it ) {
-			if ( *it == target ) {
-				alreadyInVector = true;
-				break;
-			}
-		}
-	}
-	if ( ! alreadyInVector ) {	
-		fDynamicReferences->push_back(target);
-		const_cast<ImageLoader*>(target)->fDynamicReferenceCount++;
-	}
-	//dyld::log("dyld: addDynamicReference() from %s to %s, fDynamicReferences->size()=%lu\n", this->getPath(), target->getPath(), fDynamicReferences->size());
 }
 
 int ImageLoader::compare(const ImageLoader* right) const
@@ -166,6 +135,7 @@
 	strcpy((char*)fPath, path);
 	fPathOwnedByImage = true;  // delete fPath when this image is destructed
 	fPathHash = hash(fPath);
+	fRealPath = NULL;
 }
 
 void ImageLoader::setPathUnowned(const char* path)
@@ -176,6 +146,21 @@
 	fPath = path;
 	fPathOwnedByImage = false;  
 	fPathHash = hash(fPath);
+}
+
+void ImageLoader::setPaths(const char* path, const char* realPath)
+{
+	this->setPath(path);
+	fRealPath = new char[strlen(realPath)+1];
+	strcpy((char*)fRealPath, realPath);
+}
+
+const char* ImageLoader::getRealPath() const 
+{ 
+	if ( fRealPath != NULL ) 
+		return fRealPath;
+	else
+		return fPath; 
 }
 
 
@@ -243,8 +228,6 @@
 
 bool ImageLoader::containsAddress(const void* addr) const
 {
-	if ( ! this->isLinked() )
-		return false;
 	for(unsigned int i=0, e=segmentCount(); i < e; ++i) {
 		const uint8_t* start = (const uint8_t*)segActualLoadAddress(i);
 		const uint8_t* end = (const uint8_t*)segActualEndAddress(i);
@@ -287,6 +270,16 @@
 }
 
 
+
+bool ImageLoader::dependsOn(ImageLoader* image) {
+	for(unsigned int i=0; i < libraryCount(); ++i) {
+		if ( libImage(i) == image )
+			return true;
+	}
+	return false;
+}
+
+
 static bool notInImgageList(const ImageLoader* image, const ImageLoader** dsiStart, const ImageLoader** dsiCur)
 {
 	for (const ImageLoader** p = dsiStart; p < dsiCur; ++p)
@@ -301,7 +294,6 @@
 			const ImageLoader** dsiStart, const ImageLoader**& dsiCur, const ImageLoader** dsiEnd, const ImageLoader** foundIn) const
 {
 	const ImageLoader::Symbol* sym;
-	
 	// search self
 	if ( notInImgageList(this, dsiStart, dsiCur) ) {
 		sym = this->findExportedSymbol(name, false, foundIn);
@@ -359,9 +351,46 @@
 		this->recursiveApplyInterposing(context);
 }
 
-void ImageLoader::link(const LinkContext& context, bool forceLazysBound, bool preflightOnly, const RPathChain& loaderRPaths)
-{
-	//dyld::log("ImageLoader::link(%s) refCount=%d, neverUnload=%d\n", this->getPath(), fStaticReferenceCount, fNeverUnload);
+
+uintptr_t ImageLoader::interposedAddress(const LinkContext& context, uintptr_t address, const ImageLoader* inImage, const ImageLoader* onlyInImage)
+{
+	//dyld::log("interposedAddress(0x%08llX), tupleCount=%lu\n", (uint64_t)address, fgInterposingTuples.size());
+	for (std::vector<InterposeTuple>::iterator it=fgInterposingTuples.begin(); it != fgInterposingTuples.end(); it++) {
+		//dyld::log("    interposedAddress: replacee=0x%08llX, replacement=0x%08llX, neverImage=%p, onlyImage=%p, inImage=%p\n", 
+		//				(uint64_t)it->replacee, (uint64_t)it->replacement,  it->neverImage, it->onlyImage, inImage);
+		// replace all references to 'replacee' with 'replacement'
+		if ( (address == it->replacee) && (inImage != it->neverImage) && ((it->onlyImage == NULL) || (inImage == it->onlyImage)) ) {
+			if ( context.verboseInterposing ) {
+				dyld::log("dyld interposing: replace 0x%lX with 0x%lX\n", it->replacee, it->replacement);
+			}
+			return it->replacement;
+		}
+	}
+	return address;
+}
+
+void ImageLoader::addDynamicInterposingTuples(const struct dyld_interpose_tuple array[], size_t count)
+{
+	for(size_t i=0; i < count; ++i) {
+		ImageLoader::InterposeTuple tuple;
+		tuple.replacement		= (uintptr_t)array[i].replacement;
+		tuple.neverImage		= NULL;
+		tuple.onlyImage		    = this;
+		tuple.replacee			= (uintptr_t)array[i].replacee;
+		// chain to any existing interpositions
+		for (std::vector<InterposeTuple>::iterator it=fgInterposingTuples.begin(); it != fgInterposingTuples.end(); it++) {
+			if ( (it->replacee == tuple.replacee) && (it->onlyImage == this) ) {
+				tuple.replacee = it->replacement;
+			}
+		}
+		ImageLoader::fgInterposingTuples.push_back(tuple);
+	}
+}
+
+
+void ImageLoader::link(const LinkContext& context, bool forceLazysBound, bool preflightOnly, bool neverUnload, const RPathChain& loaderRPaths)
+{
+	//dyld::log("ImageLoader::link(%s) refCount=%d, neverUnload=%d\n", this->getPath(), fDlopenReferenceCount, fNeverUnload);
 	
 	// clear error strings
 	(*context.setErrorStrings)(dyld_error_kind_none, NULL, NULL, NULL);
@@ -383,10 +412,11 @@
 	context.notifyBatch(dyld_image_state_rebased);
 	
 	uint64_t t3 = mach_absolute_time();
- 	this->recursiveBind(context, forceLazysBound);
+ 	this->recursiveBind(context, forceLazysBound, neverUnload);
 
 	uint64_t t4 = mach_absolute_time();
-	this->weakBind(context);
+	if ( !context.linkingMainExecutable )
+		this->weakBind(context);
 	uint64_t t5 = mach_absolute_time();	
 
 	context.notifyBatch(dyld_image_state_bound);
@@ -418,8 +448,7 @@
 
 void ImageLoader::printReferenceCounts()
 {
-	dyld::log("      dlopen=%d, static=%d, dynamic=%d for %s\n", 
-				fDlopenReferenceCount, fStaticReferenceCount, fDynamicReferenceCount, getPath() );
+	dyld::log("      dlopen=%d for %s\n", fDlopenReferenceCount, getPath() );
 }
 
 
@@ -431,13 +460,39 @@
 	return false;
 }
 
+
+// <rdar://problem/14412057> upward dylib initializers can be run too soon
+// To handle dangling dylibs which are upward linked but not downward, all upward linked dylibs
+// have their initialization postponed until after the recursion through downward dylibs
+// has completed.
+void ImageLoader::processInitializers(const LinkContext& context, mach_port_t thisThread,
+									 InitializerTimingList& timingInfo, ImageLoader::UninitedUpwards& images)
+{
+	uint32_t maxImageCount = context.imageCount();
+	ImageLoader::UninitedUpwards upsBuffer[maxImageCount];
+	ImageLoader::UninitedUpwards& ups = upsBuffer[0];
+	ups.count = 0;
+	// Calling recursive init on all images in images list, building a new list of
+	// uninitialized upward dependencies.
+	for (uintptr_t i=0; i < images.count; ++i) {
+		images.images[i]->recursiveInitialization(context, thisThread, timingInfo, ups);
+	}
+	// If any upward dependencies remain, init them.
+	if ( ups.count > 0 )
+		processInitializers(context, thisThread, timingInfo, ups);
+}
+
+
 void ImageLoader::runInitializers(const LinkContext& context, InitializerTimingList& timingInfo)
 {
 	uint64_t t1 = mach_absolute_time();
-	mach_port_t this_thread = mach_thread_self();
-	this->recursiveInitialization(context, this_thread, timingInfo);
+	mach_port_t thisThread = mach_thread_self();
+	ImageLoader::UninitedUpwards up;
+	up.count = 1;
+	up.images[0] = this;
+	processInitializers(context, thisThread, timingInfo, up);
 	context.notifyBatch(dyld_image_state_initialized);
-	mach_port_deallocate(mach_task_self(), this_thread);
+	mach_port_deallocate(mach_task_self(), thisThread);
 	uint64_t t2 = mach_absolute_time();
 	fgTotalInitTime += (t2 - t1);
 }
@@ -468,6 +523,29 @@
 }
 
 
+void ImageLoader::markedUsedRecursive(const std::vector<DynamicReference>& dynamicReferences)
+{
+	// already visited here
+	if ( fMarkedInUse )
+		return;
+	fMarkedInUse = true;
+	
+	// clear mark on all statically dependent dylibs
+	for(unsigned int i=0; i < libraryCount(); ++i) {
+		ImageLoader* dependentImage = libImage(i);
+		if ( dependentImage != NULL ) {
+			dependentImage->markedUsedRecursive(dynamicReferences);
+		}
+	}
+	
+	// clear mark on all dynamically dependent dylibs
+	for (std::vector<ImageLoader::DynamicReference>::const_iterator it=dynamicReferences.begin(); it != dynamicReferences.end(); ++it) {
+		if ( it->from == this )
+			it->to->markedUsedRecursive(dynamicReferences);
+	}
+	
+}
+
 unsigned int ImageLoader::recursiveUpdateDepth(unsigned int maxDepth)
 {
 	// the purpose of this phase is to make the images sortable such that 
@@ -481,7 +559,7 @@
 		unsigned int minDependentDepth = maxDepth;
 		for(unsigned int i=0; i < libraryCount(); ++i) {
 			ImageLoader* dependentImage = libImage(i);
-			if ( dependentImage != NULL ) {
+			if ( (dependentImage != NULL) && !libIsUpward(i) ) {
 				unsigned int d = dependentImage->recursiveUpdateDepth(maxDepth);
 				if ( d < minDependentDepth )
 					minDependentDepth = d;
@@ -503,7 +581,6 @@
 		fState = dyld_image_state_dependents_mapped;
 		
 		// get list of libraries this image needs
-		//dyld::log("ImageLoader::recursiveLoadLibraries() %ld = %d*%ld\n", fLibrariesCount*sizeof(DependentLibrary), fLibrariesCount, sizeof(DependentLibrary));
 		DependentLibraryInfo libraryInfos[fLibraryCount]; 
 		this->doGetDependentLibraries(libraryInfos);
 		
@@ -538,8 +615,11 @@
 				}
 				if ( fNeverUnload )
 					dependentLib->setNeverUnload();
-				if ( ! requiredLibInfo.upward )
-					dependentLib->fStaticReferenceCount += 1;
+				if ( requiredLibInfo.upward ) {
+				}
+				else { 
+					dependentLib->fIsReferencedDownward = true;
+				}
 				LibraryInfo actualInfo = dependentLib->doGetLibraryInfo();
 				depLibReRequired = requiredLibInfo.required;
 				depLibCheckSumsMatch = ( actualInfo.checksum == requiredLibInfo.info.checksum );
@@ -549,7 +629,8 @@
 					depLibReExported = dependentLib->isSubframeworkOf(context, this) || this->hasSubLibrary(context, dependentLib);
 				}
 				// check found library version is compatible
-				if ( actualInfo.minVersion < requiredLibInfo.info.minVersion ) {
+				// <rdar://problem/89200806> 0xFFFFFFFF is wildcard that matches any version
+				if ( (requiredLibInfo.info.minVersion != 0xFFFFFFFF) && (actualInfo.minVersion < requiredLibInfo.info.minVersion) ) {
 					// record values for possible use by CrashReporter or Finder
 					dyld::throwf("Incompatible library version: %s requires version %d.%d.%d or later, but %s provides version %d.%d.%d",
 							this->getShortName(), requiredLibInfo.info.minVersion >> 16, (requiredLibInfo.info.minVersion >> 8) & 0xff, requiredLibInfo.info.minVersion & 0xff,
@@ -582,8 +663,11 @@
 						(*context.setErrorStrings)(dyld_error_kind_dylib_wrong_arch, this->getPath(), requiredLibInfo.name, NULL);
 					else
 						(*context.setErrorStrings)(dyld_error_kind_dylib_missing, this->getPath(), requiredLibInfo.name, NULL);
-					dyld::throwf("Library not loaded: %s\n  Referenced from: %s\n  Reason: %s", requiredLibInfo.name, this->getPath(), msg);
+					const char* newMsg = dyld::mkstringf("Library not loaded: %s\n  Referenced from: %s\n  Reason: %s", requiredLibInfo.name, this->getRealPath(), msg);
+					free((void*)msg); 	// our free() will do nothing if msg is a string literal
+					throw newMsg;
 				}
+				free((void*)msg); 	// our free() will do nothing if msg is a string literal
 				// ok if weak library not found
 				dependentLib = NULL;
 				canUsePrelinkingInfo = false;  // this disables all prebinding, we may want to just slam import vectors for this lib to zero
@@ -676,7 +760,7 @@
 
 
 
-void ImageLoader::recursiveBind(const LinkContext& context, bool forceLazysBound)
+void ImageLoader::recursiveBind(const LinkContext& context, bool forceLazysBound, bool neverUnload)
 {
 	// Normally just non-lazy pointers are bound immediately.
 	// The exceptions are:
@@ -691,13 +775,16 @@
 			for(unsigned int i=0; i < libraryCount(); ++i) {
 				ImageLoader* dependentImage = libImage(i);
 				if ( dependentImage != NULL )
-					dependentImage->recursiveBind(context, forceLazysBound);
+					dependentImage->recursiveBind(context, forceLazysBound, neverUnload);
 			}
 			// bind this image
 			this->doBind(context, forceLazysBound);	
 			// mark if lazys are also bound
 			if ( forceLazysBound || this->usablePrebinding(context) )
 				fAllLazyPointersBound = true;
+			// mark as never-unload if requested
+			if ( neverUnload )
+				this->setNeverUnload();
 				
 			context.notifySingle(dyld_image_state_bound, this);
 		}
@@ -714,6 +801,7 @@
 {
 	if ( context.verboseWeakBind )
 		dyld::log("dyld: weak bind start:\n");
+	uint64_t t1 = mach_absolute_time();
 	// get set of ImageLoaders that participate in coalecsing
 	ImageLoader* imagesNeedingCoalescing[fgImagesRequiringCoalescing];
 	int count = context.getCoalescedImages(imagesNeedingCoalescing);
@@ -795,11 +883,10 @@
 						}
 					}
 				}
-				if ( context.verboseWeakBind )
-					dyld::log("dyld: weak binding all uses of %s to copy from %s\n", nameToCoalesce, targetImage->getShortName());
-				
 				// tell each to bind to this symbol (unless already bound)
 				if ( targetAddr != 0 ) {
+					if ( context.verboseWeakBind )
+						dyld::log("dyld: weak binding all uses of %s to copy from %s\n", nameToCoalesce, targetImage->getShortName());
 					for(int i=0; i < count; ++i) {
 						if ( strcmp(iterators[i].symbolName, nameToCoalesce) == 0 ) {
 							if ( context.verboseWeakBind )
@@ -819,6 +906,9 @@
 			imagesNeedingCoalescing[i]->fWeakSymbolsBound = true;
 		}
 	}
+	uint64_t t2 = mach_absolute_time();
+	fgTotalWeakBindTime += t2  - t1;
+	
 	if ( context.verboseWeakBind )
 		dyld::log("dyld: weak bind end\n");
 }
@@ -841,6 +931,19 @@
 	}
 }
 
+void ImageLoader::setNeverUnloadRecursive() {
+	if ( ! fNeverUnload ) {
+		// break cycles
+		fNeverUnload = true;
+		
+		// gather lower level libraries first
+		for(unsigned int i=0; i < libraryCount(); ++i) {
+			ImageLoader* dependentImage = libImage(i);
+			if ( dependentImage != NULL )
+				dependentImage->setNeverUnloadRecursive();
+		}
+	}
+}
 
 void ImageLoader::recursiveSpinLock(recursive_lock& rlock)
 {
@@ -862,7 +965,8 @@
 }
 
 
-void ImageLoader::recursiveInitialization(const LinkContext& context, mach_port_t this_thread, InitializerTimingList& timingInfo)
+void ImageLoader::recursiveInitialization(const LinkContext& context, mach_port_t this_thread,
+										  InitializerTimingList& timingInfo, UninitedUpwards& uninitUps)
 {
 	recursive_lock lock_info(this_thread);
 	recursiveSpinLock(lock_info);
@@ -875,17 +979,23 @@
 			// initialize lower level libraries first
 			for(unsigned int i=0; i < libraryCount(); ++i) {
 				ImageLoader* dependentImage = libImage(i);
-				if ( dependentImage != NULL )
-				// don't try to initialize stuff "above" me
-				if ( (dependentImage != NULL) && (dependentImage->fDepth >= fDepth) && !libIsUpward(i) )
-					dependentImage->recursiveInitialization(context, this_thread, timingInfo);
+				if ( dependentImage != NULL ) {
+					// don't try to initialize stuff "above" me yet
+					if ( libIsUpward(i) ) {
+						uninitUps.images[uninitUps.count] = dependentImage;
+						uninitUps.count++;
+					}
+					else if ( dependentImage->fDepth >= fDepth ) {
+						dependentImage->recursiveInitialization(context, this_thread, timingInfo, uninitUps);
+					}
+                }
 			}
 			
 			// record termination order
 			if ( this->needsTermination() )
 				context.terminationRecorder(this);
 			
-			// let objc know we are about to initalize this image
+			// let objc know we are about to initialize this image
 			uint64_t t1 = mach_absolute_time();
 			fState = dyld_image_state_dependents_initialized;
 			oldState = fState;
@@ -893,8 +1003,8 @@
 			
 			// initialize this image
 			bool hasInitializers = this->doInitialization(context);
-			
-			// let anyone know we finished initalizing this image
+
+			// let anyone know we finished initializing this image
 			fState = dyld_image_state_initialized;
 			oldState = fState;
 			context.notifySingle(dyld_image_state_initialized, this);
@@ -928,16 +1038,16 @@
 		}
 	}
 	if ( partTime < sUnitsPerSecond ) {
-		uint32_t milliSecondsTimesHundred = (partTime*100000)/sUnitsPerSecond;
-		uint32_t milliSeconds = milliSecondsTimesHundred/100;
-		uint32_t percentTimesTen = (partTime*1000)/totalTime;
+		uint32_t milliSecondsTimesHundred = (uint32_t)((partTime*100000)/sUnitsPerSecond);
+		uint32_t milliSeconds = (uint32_t)(milliSecondsTimesHundred/100);
+		uint32_t percentTimesTen = (uint32_t)((partTime*1000)/totalTime);
 		uint32_t percent = percentTimesTen/10;
 		dyld::log("%s: %u.%02u milliseconds (%u.%u%%)\n", msg, milliSeconds, milliSecondsTimesHundred-milliSeconds*100, percent, percentTimesTen-percent*10);
 	}
 	else {
-		uint32_t secondsTimeTen = (partTime*10)/sUnitsPerSecond;
+		uint32_t secondsTimeTen = (uint32_t)((partTime*10)/sUnitsPerSecond);
 		uint32_t seconds = secondsTimeTen/10;
-		uint32_t percentTimesTen = (partTime*1000)/totalTime;
+		uint32_t percentTimesTen = (uint32_t)((partTime*1000)/totalTime);
 		uint32_t percent = percentTimesTen/10;
 		dyld::log("%s: %u.%u seconds (%u.%u%%)\n", msg, seconds, secondsTimeTen-seconds*10, percent, percentTimesTen-percent*10);
 	}
@@ -1035,5 +1145,8 @@
 }
 
 
-
-
+VECTOR_NEVER_DESTRUCTED_IMPL(ImageLoader::InterposeTuple);
+VECTOR_NEVER_DESTRUCTED_IMPL(ImagePair);
+
+
+