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launch-cache/dsc_extractor.cpp dyld-210.2.3 dyld-360.19
--- dyld/dyld-210.2.3/launch-cache/dsc_extractor.cpp
+++ dyld/dyld-360.19/launch-cache/dsc_extractor.cpp
@@ -41,13 +41,16 @@
 #define NO_ULEB 
 #include "Architectures.hpp"
 #include "MachOFileAbstraction.hpp"
+#include "CacheFileAbstraction.hpp"
 
 #include "dsc_iterator.h"
 #include "dsc_extractor.h"
+#include "MachOTrie.hpp"
 
 #include <vector>
+#include <set>
 #include <map>
-#include <ext/hash_map>
+#include <unordered_map>
 #include <algorithm>
 #include <dispatch/dispatch.h>
 
@@ -60,15 +63,51 @@
 	uint64_t	sizem;
 };
 
+class CStringHash {
+public:
+	size_t operator()(const char* __s) const {
+		size_t __h = 0;
+		for ( ; *__s; ++__s)
+			__h = 5 * __h + *__s;
+		return __h;
+	};
+};
 class CStringEquals {
 public:
 	bool operator()(const char* left, const char* right) const { return (strcmp(left, right) == 0); }
 };
-typedef __gnu_cxx::hash_map<const char*, std::vector<seg_info>, __gnu_cxx::hash<const char*>, CStringEquals> NameToSegments;
+typedef std::unordered_map<const char*, std::vector<seg_info>, CStringHash, CStringEquals> NameToSegments;
+
+// Filter to find individual symbol re-exports in trie
+class NotReExportSymbol {
+public:
+	NotReExportSymbol(const std::set<int> &rd) :_reexportDeps(rd) {}
+	bool operator()(const mach_o::trie::Entry &entry) const {
+		bool result = isSymbolReExport(entry);
+		if (result) {
+			// <rdar://problem/17671438> Xcode 6 leaks in dyld_shared_cache_extract_dylibs
+			::free((void*)entry.name);
+			const_cast<mach_o::trie::Entry*>(&entry)->name = NULL;
+		}
+		return result;
+	}
+private:
+	bool isSymbolReExport(const mach_o::trie::Entry &entry) const {
+		if ( (entry.flags & EXPORT_SYMBOL_FLAGS_KIND_MASK) != EXPORT_SYMBOL_FLAGS_KIND_REGULAR )
+			return true;
+		if ( (entry.flags & EXPORT_SYMBOL_FLAGS_REEXPORT) == 0 )
+			return true;
+		// If the symbol comes from a dylib that is re-exported, this is not an individual symbol re-export
+		if ( _reexportDeps.count(entry.other) != 0 )
+			return true;
+		return false;
+	}
+	const std::set<int> &_reexportDeps;
+};
 
 
 template <typename A>
-int optimize_linkedit(macho_header<typename A::P>* mh, const void* mapped_cache, uint64_t* newSize) 
+int optimize_linkedit(macho_header<typename A::P>* mh, uint64_t textOffsetInCache, const void* mapped_cache, uint64_t* newSize) 
 {
 	typedef typename A::P P;
 	typedef typename A::P::E E;
@@ -87,8 +126,14 @@
 	macho_dysymtab_command<P>*	dynamicSymTab = NULL;
 	macho_linkedit_data_command<P>*	functionStarts = NULL;
 	macho_linkedit_data_command<P>*	dataInCode = NULL;
+	uint32_t exportsTrieOffset = 0;
+	uint32_t exportsTrieSize = 0;
+	std::set<int> reexportDeps;
+	int depIndex = 0;
 	for (uint32_t i = 0; i < cmd_count; ++i) {
-		if ( cmd->cmd() == macho_segment_command<P>::CMD ) {
+		switch ( cmd->cmd() ) {
+		case macho_segment_command<P>::CMD:
+			{
 			// update segment/section file offsets
 			macho_segment_command<P>* segCmd = (macho_segment_command<P>*)cmd;
 			segCmd->set_fileoff(cumulativeFileSize);
@@ -96,16 +141,20 @@
 			macho_section<P>* const sectionsEnd = &sectionsStart[segCmd->nsects()];
 			for(macho_section<P>* sect = sectionsStart; sect < sectionsEnd; ++sect) {
 				if ( sect->offset() != 0 )
-					sect->set_offset(cumulativeFileSize+sect->addr()-segCmd->vmaddr());
+					sect->set_offset((uint32_t)(cumulativeFileSize+sect->addr()-segCmd->vmaddr()));
 			}
 			if ( strcmp(segCmd->segname(), "__LINKEDIT") == 0 ) {
 				linkEditSegCmd = segCmd;
 			}
 			cumulativeFileSize += segCmd->filesize();
-		}
-		else if ( cmd->cmd() == LC_DYLD_INFO_ONLY ) {
+			}
+			break;
+		case LC_DYLD_INFO_ONLY:
+			{
 			// zero out all dyld info
 			macho_dyld_info_command<P>* dyldInfo = (macho_dyld_info_command<P>*)cmd;
+			exportsTrieOffset = dyldInfo->export_off();
+			exportsTrieSize = dyldInfo->export_size();
 			dyldInfo->set_rebase_off(0);
 			dyldInfo->set_rebase_size(0);
 			dyldInfo->set_bind_off(0);
@@ -116,18 +165,29 @@
 			dyldInfo->set_lazy_bind_size(0);
 			dyldInfo->set_export_off(0);
 			dyldInfo->set_export_size(0);
-		}
-		else if ( cmd->cmd() == LC_SYMTAB ) {
+			}
+			break;
+		case LC_SYMTAB:
 			symtab = (macho_symtab_command<P>*)cmd;
-		}
-		else if ( cmd->cmd() == LC_DYSYMTAB ) {
+			break;
+		case LC_DYSYMTAB:
 			dynamicSymTab = (macho_dysymtab_command<P>*)cmd;
-		}
-		else if ( cmd->cmd() == LC_FUNCTION_STARTS ) {
+			break;
+		case LC_FUNCTION_STARTS:
 			functionStarts = (macho_linkedit_data_command<P>*)cmd;
-		}
-		else if ( cmd->cmd() == LC_DATA_IN_CODE ) {
+			break;
+		case LC_DATA_IN_CODE:
 			dataInCode = (macho_linkedit_data_command<P>*)cmd;
+			break;
+		case LC_LOAD_DYLIB:
+		case LC_LOAD_WEAK_DYLIB:
+		case LC_REEXPORT_DYLIB:
+		case LC_LOAD_UPWARD_DYLIB:
+			++depIndex;
+			if ( cmd->cmd() == LC_REEXPORT_DYLIB ) {
+				reexportDeps.insert(depIndex);
+			}
+			break;
 		}
 		cmd = (const macho_load_command<P>*)(((uint8_t*)cmd)+cmd->cmdsize());
 	}
@@ -146,69 +206,171 @@
 		return -1;
 	}
 
-	const uint32_t newFunctionStartsOffset = linkEditSegCmd->fileoff();
+	const uint64_t newFunctionStartsOffset = linkEditSegCmd->fileoff();
 	uint32_t functionStartsSize = 0;
 	if ( functionStarts != NULL ) {
 		// copy function starts from original cache file to new mapped dylib file
 		functionStartsSize = functionStarts->datasize();
 		memcpy((char*)mh + newFunctionStartsOffset, (char*)mapped_cache + functionStarts->dataoff(), functionStartsSize);
 	}
-	const uint32_t newDataInCodeOffset = (newFunctionStartsOffset + functionStartsSize + sizeof(pint_t) - 1) & (-sizeof(pint_t)); // pointer align
+	const uint64_t newDataInCodeOffset = (newFunctionStartsOffset + functionStartsSize + sizeof(pint_t) - 1) & (-sizeof(pint_t)); // pointer align
 	uint32_t dataInCodeSize = 0;
 	if ( dataInCode != NULL ) {
 		// copy data-in-code info from original cache file to new mapped dylib file
 		dataInCodeSize = dataInCode->datasize();
 		memcpy((char*)mh + newDataInCodeOffset, (char*)mapped_cache + dataInCode->dataoff(), dataInCodeSize);
 	}
+
+	std::vector<mach_o::trie::Entry> exports;
+	if ( exportsTrieSize != 0 ) {
+		const uint8_t* exportsStart = ((uint8_t*)mapped_cache) + exportsTrieOffset; 
+		const uint8_t* exportsEnd = &exportsStart[exportsTrieSize];
+		mach_o::trie::parseTrie(exportsStart, exportsEnd, exports);
+		exports.erase(std::remove_if(exports.begin(), exports.end(), NotReExportSymbol(reexportDeps)), exports.end());
+	}
+
+	// look for local symbol info in unmapped part of shared cache
+	dyldCacheHeader<E>* header = (dyldCacheHeader<E>*)mapped_cache;
+	macho_nlist<P>* localNlists = NULL;
+	uint32_t localNlistCount = 0;
+	const char* localStrings = NULL;
+	const char* localStringsEnd = NULL;
+	if ( header->mappingOffset() > offsetof(dyld_cache_header,localSymbolsSize) ) {
+		dyldCacheLocalSymbolsInfo<E>* localInfo = (dyldCacheLocalSymbolsInfo<E>*)(((uint8_t*)mapped_cache) + header->localSymbolsOffset());
+		dyldCacheLocalSymbolEntry<E>* entries = (dyldCacheLocalSymbolEntry<E>*)(((uint8_t*)mapped_cache) + header->localSymbolsOffset() + localInfo->entriesOffset());
+		macho_nlist<P>* allLocalNlists = (macho_nlist<P>*)(((uint8_t*)localInfo) + localInfo->nlistOffset());
+		const uint32_t entriesCount = localInfo->entriesCount();
+		for (uint32_t i=0; i < entriesCount; ++i) {
+			if ( entries[i].dylibOffset() == textOffsetInCache ) {
+				uint32_t localNlistStart = entries[i].nlistStartIndex();
+				localNlistCount = entries[i].nlistCount();
+				localNlists = &allLocalNlists[localNlistStart];
+				localStrings = ((char*)localInfo) + localInfo->stringsOffset();
+				localStringsEnd = &localStrings[localInfo->stringsSize()];
+				break;
+			}
+		}
+	}
+	// compute number of symbols in new symbol table
+	const macho_nlist<P>* const mergedSymTabStart = (macho_nlist<P>*)(((uint8_t*)mapped_cache) + symtab->symoff());
+	const macho_nlist<P>* const mergedSymTabend = &mergedSymTabStart[symtab->nsyms()];
+	uint32_t newSymCount = symtab->nsyms();
+	if ( localNlists != NULL ) {
+		newSymCount = localNlistCount;
+		for (const macho_nlist<P>* s = mergedSymTabStart; s != mergedSymTabend; ++s) {
+			// skip any locals in cache
+			if ( (s->n_type() & (N_TYPE|N_EXT)) == N_SECT ) 
+				continue;
+			++newSymCount;
+		}
+	}
+	
+	// add room for N_INDR symbols for re-exported symbols
+	newSymCount += exports.size();
+
 	// copy symbol entries and strings from original cache file to new mapped dylib file
-	const uint32_t newSymTabOffset = (newDataInCodeOffset + dataInCodeSize + sizeof(pint_t) - 1) & (-sizeof(pint_t)); // pointer align
-	const uint32_t newIndSymTabOffset = newSymTabOffset + symtab->nsyms()*sizeof(macho_nlist<P>);
-	const uint32_t newStringPoolOffset = newIndSymTabOffset + dynamicSymTab->nindirectsyms()*sizeof(uint32_t);
+	const uint64_t newSymTabOffset = (newDataInCodeOffset + dataInCodeSize + sizeof(pint_t) - 1) & (-sizeof(pint_t)); // pointer align
+	const uint64_t newIndSymTabOffset = newSymTabOffset + newSymCount*sizeof(macho_nlist<P>);
+	const uint64_t newStringPoolOffset = newIndSymTabOffset + dynamicSymTab->nindirectsyms()*sizeof(uint32_t);
 	macho_nlist<P>* const newSymTabStart = (macho_nlist<P>*)(((uint8_t*)mh) + newSymTabOffset);
 	char* const newStringPoolStart = (char*)mh + newStringPoolOffset;
-	uint32_t* newIndSymTab = (uint32_t*)((char*)mh + newIndSymTabOffset);
 	const uint32_t* mergedIndSymTab = (uint32_t*)((char*)mapped_cache + dynamicSymTab->indirectsymoff());
-	const macho_nlist<P>* const mergedSymTabStart = (macho_nlist<P>*)(((uint8_t*)mapped_cache) + symtab->symoff());
-	const macho_nlist<P>* const mergedSymTabend = &mergedSymTabStart[symtab->nsyms()];
 	const char* mergedStringPoolStart = (char*)mapped_cache + symtab->stroff();
+	const char* mergedStringPoolEnd = &mergedStringPoolStart[symtab->strsize()];
 	macho_nlist<P>* t = newSymTabStart;
 	int poolOffset = 0;
+	uint32_t symbolsCopied = 0;
 	newStringPoolStart[poolOffset++] = '\0'; // first pool entry is always empty string
 	for (const macho_nlist<P>* s = mergedSymTabStart; s != mergedSymTabend; ++s) {
+		// if we have better local symbol info, skip any locals here
+		if ( (localNlists != NULL) && ((s->n_type() & (N_TYPE|N_EXT)) == N_SECT) ) 
+			continue;
 		*t = *s;
 		t->set_n_strx(poolOffset);
-		strcpy(&newStringPoolStart[poolOffset], &mergedStringPoolStart[s->n_strx()]);
-		poolOffset += (strlen(&newStringPoolStart[poolOffset]) + 1);
+		const char* symName = &mergedStringPoolStart[s->n_strx()];
+		if ( symName > mergedStringPoolEnd )
+			symName = "<corrupt symbol name>";
+		strcpy(&newStringPoolStart[poolOffset], symName);
+		poolOffset += (strlen(symName) + 1);
 		++t;
-	}
+		++symbolsCopied;
+	}
+	// <rdar://problem/16529213> recreate N_INDR symbols in extracted dylibs for debugger
+	for (std::vector<mach_o::trie::Entry>::iterator it = exports.begin(); it != exports.end(); ++it) {
+		strcpy(&newStringPoolStart[poolOffset], it->name);
+		t->set_n_strx(poolOffset);
+		poolOffset += (strlen(it->name) + 1);
+		t->set_n_type(N_INDR | N_EXT);
+		t->set_n_sect(0);
+		t->set_n_desc(0);
+		const char* importName = it->importName;
+		if ( *importName == '\0' )
+			importName = it->name;
+		strcpy(&newStringPoolStart[poolOffset], importName);
+		t->set_n_value(poolOffset);
+		poolOffset += (strlen(importName) + 1);
+		++t;
+		++symbolsCopied;
+	}
+	if ( localNlists != NULL ) {
+		// update load command to reflect new count of locals
+		dynamicSymTab->set_ilocalsym(symbolsCopied);
+		dynamicSymTab->set_nlocalsym(localNlistCount);
+		// copy local symbols
+		for (uint32_t i=0; i < localNlistCount; ++i) {
+			const char* localName = &localStrings[localNlists[i].n_strx()];
+			if ( localName > localStringsEnd )
+				localName = "<corrupt local symbol name>";
+			*t = localNlists[i];
+			t->set_n_strx(poolOffset);
+			strcpy(&newStringPoolStart[poolOffset], localName);
+			poolOffset += (strlen(localName) + 1);
+			++t;
+			++symbolsCopied;
+		}
+	}
+	
+	if ( newSymCount != symbolsCopied ) {
+		fprintf(stderr, "symbol count miscalculation\n");
+		return -1;
+	}
+	
 	// pointer align string pool size
 	while ( (poolOffset % sizeof(pint_t)) != 0 )
 		++poolOffset; 
 	// copy indirect symbol table
+	uint32_t* newIndSymTab = (uint32_t*)((char*)mh + newIndSymTabOffset);
 	memcpy(newIndSymTab, mergedIndSymTab, dynamicSymTab->nindirectsyms()*sizeof(uint32_t));
 	
 	// update load commands
 	if ( functionStarts != NULL ) {
-		functionStarts->set_dataoff(newFunctionStartsOffset);
+		functionStarts->set_dataoff((uint32_t)newFunctionStartsOffset);
 		functionStarts->set_datasize(functionStartsSize);
 	}
 	if ( dataInCode != NULL ) {
-		dataInCode->set_dataoff(newDataInCodeOffset);
+		dataInCode->set_dataoff((uint32_t)newDataInCodeOffset);
 		dataInCode->set_datasize(dataInCodeSize);
 	}
-	symtab->set_symoff(newSymTabOffset);
-	symtab->set_stroff(newStringPoolOffset);
+	symtab->set_nsyms(symbolsCopied);
+	symtab->set_symoff((uint32_t)newSymTabOffset);
+	symtab->set_stroff((uint32_t)newStringPoolOffset);
 	symtab->set_strsize(poolOffset);
 	dynamicSymTab->set_extreloff(0);
 	dynamicSymTab->set_nextrel(0);
 	dynamicSymTab->set_locreloff(0);
 	dynamicSymTab->set_nlocrel(0);
-	dynamicSymTab->set_indirectsymoff(newIndSymTabOffset);
+	dynamicSymTab->set_indirectsymoff((uint32_t)newIndSymTabOffset);
 	linkEditSegCmd->set_filesize(symtab->stroff()+symtab->strsize() - linkEditSegCmd->fileoff());
 	linkEditSegCmd->set_vmsize( (linkEditSegCmd->filesize()+4095) & (-4096) );
 	
 	// return new size
 	*newSize = (symtab->stroff()+symtab->strsize()+4095) & (-4096);
+	
+	// <rdar://problem/17671438> Xcode 6 leaks in dyld_shared_cache_extract_dylibs
+	for (std::vector<mach_o::trie::Entry>::iterator it = exports.begin(); it != exports.end(); ++it) {
+		::free((void*)(it->name));
+	}
+	
 	
 	return 0;
 }
@@ -226,7 +388,7 @@
 	lastSlash[1] = '\0';
 	struct stat stat_buf;
 	if ( stat(dirs, &stat_buf) != 0 ) {
-		const char* afterSlash = &dirs[1];
+		char* afterSlash = &dirs[1];
 		char* slash;
 		while ( (slash = strchr(afterSlash, '/')) != NULL ) {
 			*slash = '\0';
@@ -254,7 +416,7 @@
     uint32_t                nfat_archs          = 0;
 	uint32_t                offsetInFatFile     = 4096;
     uint8_t                 *base_ptr           = &dylib_data.front();
-    
+	    
 #define FH reinterpret_cast<fat_header*>(base_ptr)
 #define FA reinterpret_cast<fat_arch*>(base_ptr + (8 + (nfat_archs - 1) * sizeof(fat_arch)))
     
@@ -277,12 +439,13 @@
     FA->align                                   = OSSwapHostToBigInt32(12);
     
 	// Write regular segments into the buffer
-	uint32_t                totalSize           = 0;
-    
+	uint64_t                totalSize           = 0;
+    uint64_t				textOffsetInCache	= 0;
 	for( std::vector<seg_info>::const_iterator it=segments.begin(); it != segments.end(); ++it) {
         
         if(strcmp(it->segName, "__TEXT") == 0 ) {
-            const macho_header<P>   *textMH     = reinterpret_cast<macho_header<P>*>((uint8_t*)mapped_cache+it->offset);
+			textOffsetInCache					= it->offset;
+            const macho_header<P>   *textMH     = reinterpret_cast<macho_header<P>*>((uint8_t*)mapped_cache+textOffsetInCache);
             FA->cputype                         = OSSwapHostToBigInt32(textMH->cputype()); 
             FA->cpusubtype                      = OSSwapHostToBigInt32(textMH->cpusubtype());
             
@@ -292,7 +455,7 @@
                 
                 if(   afa->cputype == FA->cputype
                    && afa->cpusubtype == FA->cpusubtype) {
-                    fprintf(stderr, "arch already exists in fat dylib\n");
+                    //fprintf(stderr, "arch already exists in fat dylib\n");
                     dylib_data.resize(offsetInFatFile);
                     return offsetInFatFile;
                 }
@@ -309,7 +472,7 @@
     
 	// optimize linkedit
 	uint64_t                newSize             = dylib_data.size();
-	optimize_linkedit<A>(((macho_header<P>*)(base_ptr+offsetInFatFile)), mapped_cache, &newSize);
+	optimize_linkedit<A>(((macho_header<P>*)(base_ptr+offsetInFatFile)), textOffsetInCache, mapped_cache, &newSize);
 	
 	// update fat header with new file size
     dylib_data.resize(offsetInFatFile+newSize);
@@ -343,12 +506,14 @@
 	}
     
     close(cache_fd);
-    
+
 	// instantiate arch specific dylib maker
     size_t (*dylib_create_func)(const void*, std::vector<uint8_t>&, const std::vector<seg_info>&) = NULL;
 	     if ( strcmp((char*)mapped_cache, "dyld_v1    i386") == 0 ) 
 		dylib_create_func = dylib_maker<x86>;
 	else if ( strcmp((char*)mapped_cache, "dyld_v1  x86_64") == 0 ) 
+		dylib_create_func = dylib_maker<x86_64>;
+	else if ( strcmp((char*)mapped_cache, "dyld_v1 x86_64h") == 0 ) 
 		dylib_create_func = dylib_maker<x86_64>;
 	else if ( strcmp((char*)mapped_cache, "dyld_v1   armv5") == 0 ) 
 		dylib_create_func = dylib_maker<arm>;
@@ -358,6 +523,8 @@
 		dylib_create_func = dylib_maker<arm>;
 	else if ( strncmp((char*)mapped_cache, "dyld_v1  armv7", 14) == 0 ) 
 		dylib_create_func = dylib_maker<arm>;
+	else if ( strcmp((char*)mapped_cache, "dyld_v1   arm64") == 0 ) 
+		dylib_create_func = dylib_maker<arm64>;
 	else {
 		fprintf(stderr, "Error: unrecognized dyld shared cache magic.\n");
         munmap(mapped_cache, statbuf.st_size);
@@ -365,12 +532,16 @@
 	}
 
 	// iterate through all images in cache and build map of dylibs and segments
-	__block NameToSegments map;
-	dyld_shared_cache_iterate_segments_with_slide(mapped_cache, 
-		^(const char* dylib, const char* segName, uint64_t offset, uint64_t sizem, 
-							uint64_t mappedddress, uint64_t slide) {
-			map[dylib].push_back(seg_info(segName, offset, sizem));
-		});
+	__block NameToSegments  map;
+	__block int				result              = dyld_shared_cache_iterate(mapped_cache, (uint32_t)statbuf.st_size, ^(const dyld_shared_cache_dylib_info* dylibInfo, const dyld_shared_cache_segment_info* segInfo) {
+        map[dylibInfo->path].push_back(seg_info(segInfo->name, segInfo->fileOffset, segInfo->fileSize));
+    });
+
+    if(result != 0) {
+		fprintf(stderr, "Error: dyld_shared_cache_iterate_segments_with_slide failed.\n");
+        munmap(mapped_cache, statbuf.st_size);
+		return result;
+    }
 
 	// for each dylib instantiate a dylib file
     dispatch_group_t        group               = dispatch_group_create();
@@ -378,11 +549,10 @@
     dispatch_queue_t        process_queue       = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_LOW, 0);
     dispatch_queue_t        writer_queue        = dispatch_queue_create("dyld writer queue", 0);
     
-	__block int             cumulativeResult    = 0;
 	__block unsigned        count               = 0;
     
 	for ( NameToSegments::iterator it = map.begin(); it != map.end(); ++it) {
-        dispatch_semaphore_wait(sema, DISPATCH_TIME_FOREVER);
+		dispatch_semaphore_wait(sema, DISPATCH_TIME_FOREVER);
         dispatch_group_async(group, process_queue, ^{
             
             char    dylib_path[PATH_MAX];
@@ -390,7 +560,7 @@
             strcat(dylib_path, "/");
             strcat(dylib_path, it->first);
             
-            //printf("%s with %lu segments\n", dylib_path, segments.size());
+            //printf("%s with %lu segments\n", dylib_path, it->second.size());
             // make sure all directories in this path exist
             make_dirs(dylib_path);
             
@@ -398,7 +568,7 @@
             int fd = ::open(dylib_path, O_CREAT | O_EXLOCK | O_RDWR, 0644);
             if ( fd == -1 ) {
                 fprintf(stderr, "can't open or create dylib file %s, errnor=%d\n", dylib_path, errno);
-                cumulativeResult    = -1;
+                result    = -1;
                 return;
             }
             
@@ -406,7 +576,7 @@
             if (fstat(fd, &statbuf)) {
                 fprintf(stderr, "Error: stat failed for dyld file %s, errnor=%d\n", dylib_path, errno);
                 close(fd);
-                cumulativeResult    = -1;
+                result    = -1;
                 return;
             }
             
@@ -414,21 +584,21 @@
             if(pread(fd, &vec->front(), vec->size(), 0) != (long)vec->size()) {
                 fprintf(stderr, "can't read dylib file %s, errnor=%d\n", dylib_path, errno);
                 close(fd);
-                cumulativeResult    = -1;
+                result    = -1;
                 return;
             }
             
             const size_t    offset  = dylib_create_func(mapped_cache, *vec, it->second);
             
             dispatch_group_async(group, writer_queue, ^{
-                progress(count++, map.size());
+                progress(count++, (unsigned)map.size());
                 
                 if(offset != vec->size()) {
                     //Write out the first page, and everything after offset
                     if(   pwrite(fd, &vec->front(), 4096, 0) == -1 
                        || pwrite(fd, &vec->front() + offset, vec->size() - offset, offset) == -1) {
                         fprintf(stderr, "error writing, errnor=%d\n", errno);
-                        cumulativeResult    = -1;
+                        result    = -1;
                     }
                 }
                 
@@ -444,7 +614,7 @@
     dispatch_release(writer_queue);
     
     munmap(mapped_cache, statbuf.st_size);
-	return cumulativeResult;
+	return result;
 }
 
 
@@ -457,6 +627,11 @@
 
 
 #if 0 
+// test program
+#include <stdio.h>
+#include <stddef.h>
+#include <dlfcn.h>
+
 
 typedef int (*extractor_proc)(const char* shared_cache_file_path, const char* extraction_root_path,
 													void (^progress)(unsigned current, unsigned total));
@@ -468,7 +643,8 @@
 		return 1;
 	}
 	
-	void* handle = dlopen("/Developer/Platforms/iPhoneOS.platform/usr/lib/dsc_extractor.bundle", RTLD_LAZY);
+	//void* handle = dlopen("/Volumes/my/src/dyld/build/Debug/dsc_extractor.bundle", RTLD_LAZY);
+	void* handle = dlopen("/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/usr/lib/dsc_extractor.bundle", RTLD_LAZY);
 	if ( handle == NULL ) {
 		fprintf(stderr, "dsc_extractor.bundle could not be loaded\n");
 		return 1;
@@ -484,6 +660,8 @@
 	fprintf(stderr, "dyld_shared_cache_extract_dylibs_progress() => %d\n", result);
 	return 0;
 }
+
+
 #endif