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--- dyld/dyld-1335/kernel-collection-builder/KernelOptimizerLinkedit.cpp
+++ /dev/null
@@ -1,979 +0,0 @@
-/* -*- mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
- *
- * Copyright (c) 2014 Apple Inc. All rights reserved.
- *
- * @APPLE_LICENSE_HEADER_START@
- *
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
- *
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
- *
- * @APPLE_LICENSE_HEADER_END@
- */
-
-
-#include <dirent.h>
-#include <sys/errno.h>
-#include <sys/fcntl.h>
-#include <mach-o/loader.h>
-#include <mach-o/fat.h>
-#include <assert.h>
-
-#include <fstream>
-#include <string>
-#include <algorithm>
-#include <unordered_map>
-#include <unordered_set>
-
-#include "MachOFileAbstraction.hpp"
-#include "Trie.hpp"
-#include "DyldSharedCache.h"
-#include "KernelCacheBuilder.h"
-#include "MachOLoaded.h"
-
-#define ALIGN_AS_TYPE(value, type) \
- ((value + alignof(type) - 1) & (-alignof(type)))
-
-namespace {
-
-class SortedStringPool
-{
-public:
- // add a string and symbol table entry index to be updated later
- void add(uint32_t symbolIndex, const char* symbolName) {
- _map[symbolName].push_back({ symbolIndex, false });
- }
-
- // add a string and symbol table entry index to be updated later
- void addIndirect(uint32_t symbolIndex, const char* symbolName) {
- _map[symbolName].push_back({ symbolIndex, true });
- }
-
- // copy sorted strings to buffer and update all symbol's string offsets
- template <typename P>
- uint32_t copyPoolAndUpdateOffsets(char* dstStringPool, macho_nlist<P>* symbolTable) {
- // walk sorted list of strings
- dstStringPool[0] = '\0'; // tradition for start of pool to be empty string
- uint32_t poolOffset = 1;
- for (auto& entry : _map) {
- const std::string& symName = entry.first;
- // append string to pool
- strcpy(&dstStringPool[poolOffset], symName.c_str());
- // set each string offset of each symbol using it
- for (std::pair<uint32_t, bool> symbolIndexAndIndirect : entry.second) {
- if ( symbolIndexAndIndirect.second ) {
- // Indirect
- symbolTable[symbolIndexAndIndirect.first].set_n_value(poolOffset);
- } else {
- symbolTable[symbolIndexAndIndirect.first].set_n_strx(poolOffset);
- }
- }
- poolOffset += symName.size() + 1;
- }
- // return size of pool
- return poolOffset;
- }
-
- size_t size() {
- size_t size = 1;
- for (auto& entry : _map) {
- size += (entry.first.size() + 1);
- }
- return size;
- }
-
-
-private:
- std::map<std::string, std::vector<std::pair<uint32_t, bool>>> _map;
-};
-
-
-} // anonymous namespace
-
-
-struct LocalSymbolInfo
-{
- uint64_t dylibOffset;
- uint32_t nlistStartIndex;
- uint32_t nlistCount;
-};
-
-
-// Optimizes the local symbols for a given set of cache files
-struct UnmappedLocalsOptimizer {
-
- UnmappedLocalsOptimizer(uint64_t numDylibs);
-
- std::vector<uint8_t> unmappedSymbolsNListBuffer;
- uint32_t unmappedSymbolsNListCount = 0;
- std::vector<LocalSymbolInfo> symbolInfos;
- SortedStringPool symbolsStringPool;
-};
-
-UnmappedLocalsOptimizer* CacheBuilder::createLocalsOptimizer(uint64_t numDylibs) {
- return new UnmappedLocalsOptimizer(numDylibs);
-}
-
-void CacheBuilder::destroyLocalsOptimizer(UnmappedLocalsOptimizer* locals) {
- delete locals;
-}
-
-UnmappedLocalsOptimizer::UnmappedLocalsOptimizer(uint64_t numDylibs) {
- unmappedSymbolsNListBuffer.reserve(0x01000000);
- symbolInfos.reserve(numDylibs);
-}
-
-void CacheBuilder::emitLocalSymbols(UnmappedLocalsOptimizer *locals) {
- // overwrite end of un-opt linkedits to create a new unmapped region for local symbols
- const uint32_t entriesOffset = sizeof(dyld_cache_local_symbols_info);
- const uint32_t entriesCount = (uint32_t)locals->symbolInfos.size();
- const uint32_t nlistOffset = (uint32_t)align(entriesOffset + entriesCount * sizeof(dyld_cache_local_symbols_info), 4); // 16-byte align start
- const uint32_t nlistCount = locals->unmappedSymbolsNListCount;
- const uint32_t stringsSize = (uint32_t)locals->symbolsStringPool.size();
- const uint32_t stringsOffset = nlistOffset + (uint32_t)locals->unmappedSymbolsNListBuffer.size();
- // allocate buffer for local symbols
- const size_t localsBufferSize = align(stringsOffset + stringsSize, 14);
- vm_address_t localsBuffer;
- if ( ::vm_allocate(mach_task_self(), &localsBuffer, localsBufferSize, VM_FLAGS_ANYWHERE) == 0 ) {
- dyld_cache_local_symbols_info* infoHeader = (dyld_cache_local_symbols_info*)localsBuffer;
- // fill in header info
- infoHeader->nlistOffset = nlistOffset;
- infoHeader->nlistCount = nlistCount;
- infoHeader->stringsOffset = stringsOffset;
- infoHeader->stringsSize = stringsSize;
- infoHeader->entriesOffset = entriesOffset;
- infoHeader->entriesCount = entriesCount;
- // copy info for each dylib
- dyld_cache_local_symbols_entry_64* entries = (dyld_cache_local_symbols_entry_64*)(((uint8_t*)infoHeader)+entriesOffset);
- for (uint32_t i=0; i < entriesCount; ++i) {
- entries[i].dylibOffset = locals->symbolInfos[i].dylibOffset;
- entries[i].nlistStartIndex = locals->symbolInfos[i].nlistStartIndex;
- entries[i].nlistCount = locals->symbolInfos[i].nlistCount;
- }
- // copy nlists
- uint8_t* newLocalsSymbolTable = (uint8_t*)(localsBuffer+nlistOffset);
- ::memcpy(newLocalsSymbolTable, locals->unmappedSymbolsNListBuffer.data(), locals->unmappedSymbolsNListBuffer.size());
- // copy string pool
- if ( _is64 ) {
- typedef Pointer64<LittleEndian> P;
- locals->symbolsStringPool.copyPoolAndUpdateOffsets<P>(((char*)infoHeader)+stringsOffset,
- (macho_nlist<P>*)newLocalsSymbolTable);
- } else {
- typedef Pointer32<LittleEndian> P;
- locals->symbolsStringPool.copyPoolAndUpdateOffsets<P>(((char*)infoHeader)+stringsOffset,
- (macho_nlist<P>*)newLocalsSymbolTable);
- }
-
- // return buffer of local symbols, caller to free() it
- _localSymbolsRegion.buffer = (uint8_t*)localsBuffer;
- _localSymbolsRegion.bufferSize = localsBufferSize;
- _localSymbolsRegion.sizeInUse = localsBufferSize;
- }
- else {
- _diagnostics.warning("could not allocate local symbols");
- }
-}
-
-
-template <typename P>
-class LinkeditOptimizer {
-public:
- LinkeditOptimizer(const void* containerBuffer, macho_header<P>* mh, const char* dylibID,
- Diagnostics& diag);
-
- uint32_t linkeditSize() { return _linkeditSize; }
- uint64_t linkeditAddr() { return _linkeditAddr; }
- const char* dylibID() { return _dylibID; }
- void copyWeakBindingInfo(uint8_t* newLinkEditContent, uint32_t& offset);
- void copyLazyBindingInfo(uint8_t* newLinkEditContent, uint32_t& offset);
- void copyBindingInfo(uint8_t* newLinkEditContent, uint32_t& offset);
- void copyExportInfo(uint8_t* newLinkEditContent, uint32_t& offset);
- void copyExportedSymbols(uint8_t* newLinkEditContent, SortedStringPool& stringPool, uint32_t& offset, uint32_t& symbolIndex);
- void copyImportedSymbols(uint8_t* newLinkEditContent, SortedStringPool& stringPool, uint32_t& offset, uint32_t& symbolIndex);
- void copyLocalSymbols(uint8_t* newLinkEditContent, SortedStringPool& stringPool, uint32_t& offset, uint32_t& symbolIndex,
- UnmappedLocalsOptimizer *locals);
- void copyFunctionStarts(uint8_t* newLinkEditContent, uint32_t& offset);
- void copyDataInCode(uint8_t* newLinkEditContent, uint32_t& offset);
- void copyIndirectSymbolTable(uint8_t* newLinkEditContent, uint32_t& offset);
- void updateLoadCommands(uint32_t linkeditStartOffset, uint64_t mergedLinkeditAddr, uint64_t newLinkeditSize,
- uint32_t sharedSymbolTableStartOffset, uint32_t sharedSymbolTableCount,
- uint32_t sharedSymbolStringsOffset, uint32_t sharedSymbolStringsSize);
-
- typedef CacheBuilder::DylibStripMode DylibStripMode;
- void setStripMode(DylibStripMode stripMode);
-
- macho_header<P>* machHeader() { return _mh; }
- const std::vector<const char*> getDownwardDependents() { return _downDependentPaths; }
- const std::vector<const char*> getAllDependents() { return _allDependentPaths; }
- const std::vector<const char*> getReExportPaths() { return _reExportPaths; }
- const std::vector<uint64_t> initializerAddresses() { return _initializerAddresses; }
- const std::vector<macho_section<P>*> dofSections() { return _dofSections; }
- uint32_t exportsTrieLinkEditOffset() { return _newExportInfoOffset; }
- uint32_t exportsTrieLinkEditSize() { return _exportInfoSize; }
- uint32_t weakBindingLinkEditOffset() { return _newWeakBindingInfoOffset; }
- uint32_t weakBindingLinkEditSize() { return _newWeakBindingSize; }
- uint64_t dyldSectionAddress() { return _dyldSectionAddr; }
- const std::vector<macho_segment_command<P>*>& segCmds() { return _segCmds; }
-
-
- static void optimizeLinkedit(Diagnostics& diagnostics,
- CacheBuilder::Region& readOnlyRegion,
- uint64_t nonLinkEditReadOnlySize,
- const void* containerBuffer,
- UnmappedLocalsOptimizer* localSymbolsOptimizer,
- DyldSharedCache::LocalSymbolsMode localSymbolMode,
- const std::vector<std::tuple<const mach_header*, const char*, DylibStripMode>>& images);
- static void mergeLinkedits(Diagnostics& diagnostics,
- CacheBuilder::Region& readOnlyRegion,
- uint64_t nonLinkEditReadOnlySize,
- UnmappedLocalsOptimizer* localSymbolsOptimizer,
- DyldSharedCache::LocalSymbolsMode localSymbolMode,
- std::vector<LinkeditOptimizer<P>*>& optimizers);
-
-private:
-
- typedef typename P::uint_t pint_t;
- typedef typename P::E E;
-
- macho_header<P>* _mh;
- const void* _containerBuffer;
- Diagnostics& _diagnostics;
- uint32_t _linkeditSize = 0;
- uint64_t _linkeditAddr = 0;
- const uint8_t* _linkeditBias = nullptr;
- const char* _dylibID = nullptr;
- macho_symtab_command<P>* _symTabCmd = nullptr;
- macho_dysymtab_command<P>* _dynSymTabCmd = nullptr;
- macho_dyld_info_command<P>* _dyldInfo = nullptr;
- macho_linkedit_data_command<P>* _exportTrieCmd = nullptr;
- macho_linkedit_data_command<P>* _functionStartsCmd = nullptr;
- macho_linkedit_data_command<P>* _dataInCodeCmd = nullptr;
- std::vector<macho_segment_command<P>*> _segCmds;
- std::unordered_map<uint32_t,uint32_t> _oldToNewSymbolIndexes;
- std::vector<const char*> _reExportPaths;
- std::vector<const char*> _downDependentPaths;
- std::vector<const char*> _allDependentPaths;
- std::vector<uint64_t> _initializerAddresses;
- std::vector<macho_section<P>*> _dofSections;
- uint32_t _newWeakBindingInfoOffset = 0;
- uint32_t _newLazyBindingInfoOffset = 0;
- uint32_t _newBindingInfoOffset = 0;
- uint32_t _newExportInfoOffset = 0;
- uint32_t _exportInfoSize = 0;
- uint32_t _newWeakBindingSize = 0;
- uint32_t _newExportedSymbolsStartIndex = 0;
- uint32_t _newExportedSymbolCount = 0;
- uint32_t _newImportedSymbolsStartIndex = 0;
- uint32_t _newImportedSymbolCount = 0;
- uint32_t _newLocalSymbolsStartIndex = 0;
- uint32_t _newLocalSymbolCount = 0;
- uint32_t _newFunctionStartsOffset = 0;
- uint32_t _newDataInCodeOffset = 0;
- uint32_t _newIndirectSymbolTableOffset = 0;
- uint64_t _dyldSectionAddr = 0;
- DylibStripMode _stripMode = DylibStripMode::stripAll;
-};
-
-
-template <typename P>
-LinkeditOptimizer<P>::LinkeditOptimizer(const void* containerBuffer, macho_header<P>* mh,
- const char* dylibID, Diagnostics& diag)
-: _mh(mh), _containerBuffer(containerBuffer), _diagnostics(diag), _dylibID(dylibID)
-{
- const unsigned origLoadCommandsSize = mh->sizeofcmds();
- unsigned bytesRemaining = origLoadCommandsSize;
- unsigned removedCount = 0;
- uint64_t textSegAddr = 0;
- int64_t slide = 0;
- const macho_load_command<P>* const cmds = (macho_load_command<P>*)((uint8_t*)mh + sizeof(macho_header<P>));
- const uint32_t cmdCount = mh->ncmds();
- const macho_load_command<P>* cmd = cmds;
- const macho_dylib_command<P>* dylibCmd;
- const macho_routines_command<P>* routinesCmd;
- macho_segment_command<P>* segCmd;
- for (uint32_t i = 0; i < cmdCount; ++i) {
- bool remove = false;
- switch (cmd->cmd()) {
- case LC_SYMTAB:
- _symTabCmd = (macho_symtab_command<P>*)cmd;
- break;
- case LC_DYSYMTAB:
- _dynSymTabCmd = (macho_dysymtab_command<P>*)cmd;
- break;
- case LC_DYLD_INFO:
- case LC_DYLD_INFO_ONLY:
- _dyldInfo = (macho_dyld_info_command<P>*)cmd;
- _exportInfoSize = _dyldInfo->export_size();
- break;
- case LC_FUNCTION_STARTS:
- _functionStartsCmd = (macho_linkedit_data_command<P>*)cmd;
- break;
- case LC_DATA_IN_CODE:
- _dataInCodeCmd = (macho_linkedit_data_command<P>*)cmd;
- break;
- case LC_DYLD_EXPORTS_TRIE:
- _exportTrieCmd = (macho_linkedit_data_command<P>*)cmd;
- _exportInfoSize = _exportTrieCmd->datasize();
- break;
- case LC_ROUTINES:
- case LC_ROUTINES_64:
- routinesCmd = (macho_routines_command<P>*)cmd;
- _initializerAddresses.push_back(routinesCmd->init_address());
- break;
- case LC_REEXPORT_DYLIB:
- case LC_LOAD_DYLIB:
- case LC_LOAD_WEAK_DYLIB:
- case LC_LOAD_UPWARD_DYLIB:
- dylibCmd = (macho_dylib_command<P>*)cmd;
- _allDependentPaths.push_back(dylibCmd->name());
- if ( cmd->cmd() != LC_LOAD_UPWARD_DYLIB )
- _downDependentPaths.push_back(dylibCmd->name());
- if ( cmd->cmd() == LC_REEXPORT_DYLIB )
- _reExportPaths.push_back(dylibCmd->name());
- break;
- case macho_segment_command<P>::CMD:
- segCmd = (macho_segment_command<P>*)cmd;
- _segCmds.push_back(segCmd);
- if ( strcmp(segCmd->segname(), "__TEXT") == 0 ) {
- textSegAddr = segCmd->vmaddr();
- slide = (uint64_t)mh - textSegAddr;
- }
- else if ( strcmp(segCmd->segname(), "__LINKEDIT") == 0 ) {
- _linkeditAddr = segCmd->vmaddr();
- _linkeditBias = (uint8_t*)mh + (_linkeditAddr - textSegAddr) - segCmd->fileoff();
- _linkeditSize = (uint32_t)segCmd->vmsize();
- }
- else if ( segCmd->nsects() > 0 ) {
- macho_section<P>* const sectionsStart = (macho_section<P>*)((uint8_t*)segCmd + sizeof(macho_segment_command<P>));
- macho_section<P>* const sectionsEnd = §ionsStart[segCmd->nsects()];
- for (macho_section<P>* sect=sectionsStart; sect < sectionsEnd; ++sect) {
- const uint8_t type = sect->flags() & SECTION_TYPE;
- if ( type == S_MOD_INIT_FUNC_POINTERS ) {
- const pint_t* inits = (pint_t*)(sect->addr()+slide);
- const size_t count = sect->size() / sizeof(pint_t);
- for (size_t j=0; j < count; ++j) {
- uint64_t func = P::getP(inits[j]);
- _initializerAddresses.push_back(func);
- }
- }
- else if ( type == S_INIT_FUNC_OFFSETS ) {
- const uint32_t* inits = (uint32_t*)(sect->addr()+slide);
- const size_t count = sect->size() / sizeof(uint32_t);
- for (size_t j=0; j < count; ++j) {
- uint32_t funcOffset = E::get32(inits[j]);
- _initializerAddresses.push_back(textSegAddr + funcOffset);
- }
- }
- else if ( type == S_DTRACE_DOF ) {
- _dofSections.push_back(sect);
- }
- else if ( (strcmp(sect->sectname(), "__dyld") == 0) && (strncmp(sect->segname(), "__DATA", 6) == 0) ) {
- _dyldSectionAddr = sect->addr();
- }
- }
- }
- break;
- case LC_DYLD_CHAINED_FIXUPS:
- case LC_SEGMENT_SPLIT_INFO:
- remove = true;
- break;
- }
- uint32_t cmdSize = cmd->cmdsize();
- macho_load_command<P>* nextCmd = (macho_load_command<P>*)(((uint8_t*)cmd)+cmdSize);
- if ( remove ) {
- ::memmove((void*)cmd, (void*)nextCmd, bytesRemaining);
- ++removedCount;
- }
- else {
- bytesRemaining -= cmdSize;
- cmd = nextCmd;
- }
- }
- // zero out stuff removed
- ::bzero((void*)cmd, bytesRemaining);
- // update header
- mh->set_ncmds(cmdCount - removedCount);
- mh->set_sizeofcmds(origLoadCommandsSize - bytesRemaining);
-}
-
-template <typename P>
-void LinkeditOptimizer<P>::setStripMode(DylibStripMode stripMode) {
- _stripMode = stripMode;
-}
-
-/*
-static void dumpLoadCommands(const uint8_t* mheader)
-{
- const mach_header* const mh = (mach_header*)mheader;
- const uint32_t cmd_count = mh->ncmds;
- bool is64 = (mh->magic == MH_MAGIC_64);
- const load_command* cmds = (load_command*)(mheader + (is64 ? sizeof(mach_header_64) : sizeof(mach_header)));
- const load_command* cmd = cmds;
- const segment_command* segCmd;
- const segment_command_64* seg64Cmd;
- const symtab_command* symTab;
- const linkedit_data_command* leData;
- const uint8_t* linkEditBias = NULL;
- for (uint32_t i = 0; i < cmd_count; ++i) {
- switch (cmd->cmd) {
- case LC_SEGMENT:
- segCmd = (const segment_command*)cmd;
- printf("LC_SEGMENT\n");
- printf(" segname = %s\n", segCmd->segname);
- printf(" vmaddr = 0x%08X\n", segCmd->vmaddr);
- printf(" vmsize = 0x%08X\n", segCmd->vmsize);
- printf(" fileoff = 0x%08X\n", segCmd->fileoff);
- printf(" filesize = 0x%08X\n", segCmd->filesize);
- if ( strcmp(segCmd->segname, "__TEXT") == 0 ) {
- linkEditBias = mheader - segCmd->fileoff;
- }
- break;
- case LC_SEGMENT_64:
- seg64Cmd = (const segment_command_64*)cmd;
- printf("LC_SEGMENT_64\n");
- printf(" segname = %s\n", seg64Cmd->segname);
- printf(" vmaddr = 0x%09llX\n", seg64Cmd->vmaddr);
- printf(" vmsize = 0x%09llX\n", seg64Cmd->vmsize);
- printf(" fileoff = 0x%09llX\n", seg64Cmd->fileoff);
- printf(" filesize = 0x%09llX\n", seg64Cmd->filesize);
- if ( strcmp(seg64Cmd->segname, "__TEXT") == 0 ) {
- linkEditBias = mheader - seg64Cmd->fileoff;
- }
- break;
- case LC_SYMTAB:
- symTab = (const symtab_command*)cmd;
- printf("LC_SYMTAB\n");
- printf(" symoff = 0x%08X\n", symTab->symoff);
- printf(" nsyms = 0x%08X\n", symTab->nsyms);
- printf(" stroff = 0x%08X\n", symTab->stroff);
- printf(" strsize = 0x%08X\n", symTab->strsize);
- {
- const char* strPool = (char*)&linkEditBias[symTab->stroff];
- const nlist_64* sym0 = (nlist_64*)(&linkEditBias[symTab->symoff]);
- printf(" sym[0].n_strx = 0x%08X (%s)\n", sym0->n_un.n_strx, &strPool[sym0->n_un.n_strx]);
- printf(" sym[0].n_type = 0x%02X\n", sym0->n_type);
- printf(" sym[0].n_sect = 0x%02X\n", sym0->n_sect);
- printf(" sym[0].n_desc = 0x%04X\n", sym0->n_desc);
- printf(" sym[0].n_value = 0x%llX\n", sym0->n_value);
- const nlist_64* sym1 = (nlist_64*)(&linkEditBias[symTab->symoff+16]);
- printf(" sym[1].n_strx = 0x%08X (%s)\n", sym1->n_un.n_strx, &strPool[sym1->n_un.n_strx]);
- printf(" sym[1].n_type = 0x%02X\n", sym1->n_type);
- printf(" sym[1].n_sect = 0x%02X\n", sym1->n_sect);
- printf(" sym[1].n_desc = 0x%04X\n", sym1->n_desc);
- printf(" sym[1].n_value = 0x%llX\n", sym1->n_value);
- }
- break;
- case LC_FUNCTION_STARTS:
- leData = (const linkedit_data_command*)cmd;
- printf("LC_FUNCTION_STARTS\n");
- printf(" dataoff = 0x%08X\n", leData->dataoff);
- printf(" datasize = 0x%08X\n", leData->datasize);
- default:
- //printf("0x%08X\n", cmd->cmd);
- break;
- }
- cmd = (const load_command*)(((uint8_t*)cmd)+cmd->cmdsize);
- }
-}
-*/
-
-template <typename P>
-void LinkeditOptimizer<P>::updateLoadCommands(uint32_t mergedLinkeditStartOffset, uint64_t mergedLinkeditAddr, uint64_t newLinkeditSize,
- uint32_t sharedSymbolTableStartOffset, uint32_t sharedSymbolTableCount,
- uint32_t sharedSymbolStringsOffset, uint32_t sharedSymbolStringsSize)
-{
- // update __LINKEDIT segment in all dylibs to overlap the same shared region
- for (macho_segment_command<P>* segCmd : _segCmds) {
- if ( strcmp(segCmd->segname(), "__LINKEDIT") == 0 ) {
- segCmd->set_vmaddr(mergedLinkeditAddr);
- segCmd->set_vmsize(newLinkeditSize);
- segCmd->set_fileoff(mergedLinkeditStartOffset);
- segCmd->set_filesize(newLinkeditSize);
- }
- else if ( strcmp(segCmd->segname(), "__TEXT") == 0 ) {
- // HACK until lldb fixed in: <rdar://problem/20357466> DynamicLoaderMacOSXDYLD fixes for Monarch dyld shared cache
- //segCmd->set_fileoff(0);
-
- }
- }
-
- // update symbol table to point to shared symbol table
- _symTabCmd->set_symoff(mergedLinkeditStartOffset + sharedSymbolTableStartOffset + _newLocalSymbolsStartIndex*sizeof(macho_nlist<P>));
- _symTabCmd->set_nsyms(_newLocalSymbolCount+_newExportedSymbolCount+_newImportedSymbolCount);
- _symTabCmd->set_stroff(mergedLinkeditStartOffset + sharedSymbolStringsOffset);
- _symTabCmd->set_strsize(sharedSymbolStringsSize);
-
- // update dynamic symbol table to have proper offsets into shared symbol table
- if ( _dynSymTabCmd != nullptr ) {
- _dynSymTabCmd->set_ilocalsym(0);
- _dynSymTabCmd->set_nlocalsym(_newLocalSymbolCount);
- _dynSymTabCmd->set_iextdefsym(_newExportedSymbolsStartIndex-_newLocalSymbolsStartIndex);
- _dynSymTabCmd->set_nextdefsym(_newExportedSymbolCount);
- _dynSymTabCmd->set_iundefsym(_newImportedSymbolsStartIndex-_newLocalSymbolsStartIndex);
- _dynSymTabCmd->set_nundefsym(_newImportedSymbolCount);
- _dynSymTabCmd->set_tocoff(0);
- _dynSymTabCmd->set_ntoc(0);
- _dynSymTabCmd->set_modtaboff(0);
- _dynSymTabCmd->set_nmodtab(0);
- _dynSymTabCmd->set_indirectsymoff(mergedLinkeditStartOffset + _newIndirectSymbolTableOffset);
- _dynSymTabCmd->set_extreloff(0);
- _dynSymTabCmd->set_nextrel(0);
- _dynSymTabCmd->set_locreloff(0);
- _dynSymTabCmd->set_nlocrel(0);
- }
-
- // update dyld info
- if ( _dyldInfo != nullptr ) {
- _dyldInfo->set_rebase_off(0);
- _dyldInfo->set_rebase_size(0);
- _dyldInfo->set_bind_off(_dyldInfo->bind_size() ? mergedLinkeditStartOffset + _newBindingInfoOffset : 0);
- _dyldInfo->set_weak_bind_off(_dyldInfo->weak_bind_size() ? mergedLinkeditStartOffset + _newWeakBindingInfoOffset : 0 );
- _dyldInfo->set_lazy_bind_off(_dyldInfo->lazy_bind_size() ? mergedLinkeditStartOffset + _newLazyBindingInfoOffset : 0 );
- _dyldInfo->set_export_off(mergedLinkeditStartOffset + _newExportInfoOffset);
- } else if ( _exportTrieCmd != nullptr ) {
- _exportTrieCmd->set_dataoff(mergedLinkeditStartOffset + _newExportInfoOffset);
- }
-
- // update function-starts
- if ( _functionStartsCmd != nullptr )
- _functionStartsCmd->set_dataoff(mergedLinkeditStartOffset+_newFunctionStartsOffset);
-
- // update data-in-code
- if ( _dataInCodeCmd != nullptr )
- _dataInCodeCmd->set_dataoff(mergedLinkeditStartOffset+_newDataInCodeOffset);
-}
-
-template <typename P>
-void LinkeditOptimizer<P>::copyWeakBindingInfo(uint8_t* newLinkEditContent, uint32_t& offset)
-{
- if ( _dyldInfo == nullptr )
- return;
- unsigned size = _dyldInfo->weak_bind_size();
- if ( size != 0 ) {
- ::memcpy(&newLinkEditContent[offset], &_linkeditBias[_dyldInfo->weak_bind_off()], size);
- _newWeakBindingInfoOffset = offset;
- _newWeakBindingSize = size;
- offset += size;
- }
-}
-
-
-template <typename P>
-void LinkeditOptimizer<P>::copyLazyBindingInfo(uint8_t* newLinkEditContent, uint32_t& offset)
-{
- if ( _dyldInfo == nullptr )
- return;
- unsigned size = _dyldInfo->lazy_bind_size();
- if ( size != 0 ) {
- ::memcpy(&newLinkEditContent[offset], &_linkeditBias[_dyldInfo->lazy_bind_off()], size);
- _newLazyBindingInfoOffset = offset;
- offset += size;
- }
-}
-
-template <typename P>
-void LinkeditOptimizer<P>::copyBindingInfo(uint8_t* newLinkEditContent, uint32_t& offset)
-{
- if ( _dyldInfo == nullptr )
- return;
- unsigned size = _dyldInfo->bind_size();
- if ( size != 0 ) {
- ::memcpy(&newLinkEditContent[offset], &_linkeditBias[_dyldInfo->bind_off()], size);
- _newBindingInfoOffset = offset;
- offset += size;
- }
-}
-
-template <typename P>
-void LinkeditOptimizer<P>::copyExportInfo(uint8_t* newLinkEditContent, uint32_t& offset)
-{
- if ( (_dyldInfo == nullptr) && (_exportTrieCmd == nullptr) )
- return;
-
- uint32_t exportOffset = _exportTrieCmd ? _exportTrieCmd->dataoff() : _dyldInfo->export_off();
- uint32_t exportSize = _exportTrieCmd ? _exportTrieCmd->datasize() : _dyldInfo->export_size();
- if ( exportSize != 0 ) {
- ::memcpy(&newLinkEditContent[offset], &_linkeditBias[exportOffset], exportSize);
- _newExportInfoOffset = offset;
- offset += exportSize;
- }
-}
-
-
-template <typename P>
-void LinkeditOptimizer<P>::copyFunctionStarts(uint8_t* newLinkEditContent, uint32_t& offset)
-{
- if ( _functionStartsCmd == nullptr )
- return;
- unsigned size = _functionStartsCmd->datasize();
- ::memcpy(&newLinkEditContent[offset], &_linkeditBias[_functionStartsCmd->dataoff()], size);
- _newFunctionStartsOffset = offset;
- offset += size;
-}
-
-template <typename P>
-void LinkeditOptimizer<P>::copyDataInCode(uint8_t* newLinkEditContent, uint32_t& offset)
-{
- if ( _dataInCodeCmd == nullptr )
- return;
- unsigned size = _dataInCodeCmd->datasize();
- ::memcpy(&newLinkEditContent[offset], &_linkeditBias[_dataInCodeCmd->dataoff()], size);
- _newDataInCodeOffset = offset;
- offset += size;
-}
-
-
-template <typename P>
-void LinkeditOptimizer<P>::copyLocalSymbols(uint8_t* newLinkEditContent, SortedStringPool& stringPool,
- uint32_t& offset, uint32_t& symbolIndex,
- UnmappedLocalsOptimizer *locals)
-{
- LocalSymbolInfo* localInfo = nullptr;
- if ( locals != nullptr ) {
- localInfo = &locals->symbolInfos.emplace_back();
- localInfo->dylibOffset = (((uint8_t*)_mh) - (uint8_t*)_containerBuffer);
- localInfo->nlistStartIndex = locals->unmappedSymbolsNListCount;
- localInfo->nlistCount = 0;
- }
-
- _newLocalSymbolsStartIndex = symbolIndex;
- _newLocalSymbolCount = 0;
-
- switch (_stripMode) {
- case CacheBuilder::DylibStripMode::stripNone:
- case CacheBuilder::DylibStripMode::stripExports:
- break;
- case CacheBuilder::DylibStripMode::stripLocals:
- case CacheBuilder::DylibStripMode::stripAll:
- return;
- }
-
- if ( _dynSymTabCmd == nullptr )
- return;
-
- const char* strings = (char*)&_linkeditBias[_symTabCmd->stroff()];
- const macho_nlist<P>* const symbolTable = (macho_nlist<P>*)(&_linkeditBias[_symTabCmd->symoff()]);
- const macho_nlist<P>* const firstExport = &symbolTable[_dynSymTabCmd->ilocalsym()];
- const macho_nlist<P>* const lastExport = &symbolTable[_dynSymTabCmd->ilocalsym()+_dynSymTabCmd->nlocalsym()];
- for (const macho_nlist<P>* entry = firstExport; entry < lastExport; ++entry) {
- if ( (entry->n_type() & N_TYPE) != N_SECT)
- continue;
- if ( (entry->n_type() & N_STAB) != 0)
- continue;
- const char* name = &strings[entry->n_strx()];
- macho_nlist<P>* newSymbolEntry = (macho_nlist<P>*)&newLinkEditContent[offset];
- *newSymbolEntry = *entry;
- if ( locals != nullptr ) {
- // if removing local symbols, change __text symbols to "<redacted>" so backtraces don't have bogus names
- if ( entry->n_sect() == 1 ) {
- stringPool.add(symbolIndex, "<redacted>");
- ++symbolIndex;
- offset += sizeof(macho_nlist<P>);
- }
- // copy local symbol to unmmapped locals area
- locals->symbolsStringPool.add(locals->unmappedSymbolsNListCount, name);
- auto it = locals->unmappedSymbolsNListBuffer.insert(locals->unmappedSymbolsNListBuffer.end(), sizeof(macho_nlist<P>), 0);
- macho_nlist<P>* unmappedSymbolEntry = (macho_nlist<P>*)&*it;
- *unmappedSymbolEntry = *entry;
- unmappedSymbolEntry->set_n_strx(0);
- ++locals->unmappedSymbolsNListCount;
- }
- else {
- stringPool.add(symbolIndex, name);
- ++symbolIndex;
- offset += sizeof(macho_nlist<P>);
- }
- }
- _newLocalSymbolCount = symbolIndex - _newLocalSymbolsStartIndex;
-
- if ( locals != nullptr ) {
- localInfo->nlistCount = locals->unmappedSymbolsNListCount - localInfo->nlistStartIndex;
- }
-}
-
-
-template <typename P>
-void LinkeditOptimizer<P>::copyExportedSymbols(uint8_t* newLinkEditContent, SortedStringPool& stringPool, uint32_t& offset, uint32_t& symbolIndex)
-{
- _newExportedSymbolsStartIndex = symbolIndex;
- _newExportedSymbolCount = 0;
-
- switch (_stripMode) {
- case CacheBuilder::DylibStripMode::stripNone:
- case CacheBuilder::DylibStripMode::stripLocals:
- break;
- case CacheBuilder::DylibStripMode::stripExports:
- case CacheBuilder::DylibStripMode::stripAll:
- return;
- }
-
- if ( _dynSymTabCmd == nullptr )
- return;
-
- const char* strings = (char*)&_linkeditBias[_symTabCmd->stroff()];
- const macho_nlist<P>* const symbolTable = (macho_nlist<P>*)(&_linkeditBias[_symTabCmd->symoff()]);
- const macho_nlist<P>* const firstExport = &symbolTable[_dynSymTabCmd->iextdefsym()];
- const macho_nlist<P>* const lastExport = &symbolTable[_dynSymTabCmd->iextdefsym()+_dynSymTabCmd->nextdefsym()];
- uint32_t oldSymbolIndex = _dynSymTabCmd->iextdefsym();
- for (const macho_nlist<P>* entry = firstExport; entry < lastExport; ++entry, ++oldSymbolIndex) {
- if ( (entry->n_type() & N_TYPE) != N_SECT)
- continue;
- const char* name = &strings[entry->n_strx()];
- if ( strncmp(name, ".objc_", 6) == 0 )
- continue;
- if ( strncmp(name, "$ld$", 4) == 0 )
- continue;
- macho_nlist<P>* newSymbolEntry = (macho_nlist<P>*)&newLinkEditContent[offset];
- *newSymbolEntry = *entry;
- newSymbolEntry->set_n_strx(0);
- stringPool.add(symbolIndex, name);
- _oldToNewSymbolIndexes[oldSymbolIndex] = symbolIndex - _newLocalSymbolsStartIndex;
- ++symbolIndex;
- offset += sizeof(macho_nlist<P>);
- }
- _newExportedSymbolCount = symbolIndex - _newExportedSymbolsStartIndex;
-}
-
-template <typename P>
-void LinkeditOptimizer<P>::copyImportedSymbols(uint8_t* newLinkEditContent, SortedStringPool& stringPool, uint32_t& offset, uint32_t& symbolIndex)
-{
- _newImportedSymbolsStartIndex = symbolIndex;
- _newImportedSymbolCount = 0;
-
- if ( _dynSymTabCmd == nullptr )
- return;
-
- switch (_stripMode) {
- case CacheBuilder::DylibStripMode::stripNone:
- break;
- case CacheBuilder::DylibStripMode::stripLocals:
- case CacheBuilder::DylibStripMode::stripExports:
- case CacheBuilder::DylibStripMode::stripAll:
- return;
- }
-
- const char* strings = (char*)&_linkeditBias[_symTabCmd->stroff()];
- const macho_nlist<P>* const symbolTable = (macho_nlist<P>*)(&_linkeditBias[_symTabCmd->symoff()]);
- const macho_nlist<P>* const firstImport = &symbolTable[_dynSymTabCmd->iundefsym()];
- const macho_nlist<P>* const lastImport = &symbolTable[_dynSymTabCmd->iundefsym()+_dynSymTabCmd->nundefsym()];
- uint32_t oldSymbolIndex = _dynSymTabCmd->iundefsym();
- for (const macho_nlist<P>* entry = firstImport; entry < lastImport; ++entry, ++oldSymbolIndex) {
- if ( (entry->n_type() & N_TYPE) != N_UNDF)
- continue;
- const char* name = &strings[entry->n_strx()];
- macho_nlist<P>* newSymbolEntry = (macho_nlist<P>*)&newLinkEditContent[offset];
- *newSymbolEntry = *entry;
- newSymbolEntry->set_n_strx(0);
- stringPool.add(symbolIndex, name);
- _oldToNewSymbolIndexes[oldSymbolIndex] = symbolIndex - _newLocalSymbolsStartIndex;
- ++symbolIndex;
- offset += sizeof(macho_nlist<P>);
- }
- _newImportedSymbolCount = symbolIndex - _newImportedSymbolsStartIndex;
-}
-
-template <typename P>
-void LinkeditOptimizer<P>::copyIndirectSymbolTable(uint8_t* newLinkEditContent, uint32_t& offset)
-{
- _newIndirectSymbolTableOffset = offset;
-
- if ( _dynSymTabCmd == nullptr )
- return;
-
- const uint32_t* const indirectTable = (uint32_t*)&_linkeditBias[_dynSymTabCmd->indirectsymoff()];
- uint32_t* newIndirectTable = (uint32_t*)&newLinkEditContent[offset];
- for (uint32_t i=0; i < _dynSymTabCmd->nindirectsyms(); ++i) {
- uint32_t symbolIndex = E::get32(indirectTable[i]);
- if ( (symbolIndex == INDIRECT_SYMBOL_ABS) || (symbolIndex == INDIRECT_SYMBOL_LOCAL) )
- E::set32(newIndirectTable[i], symbolIndex);
- else
- E::set32(newIndirectTable[i], _oldToNewSymbolIndexes[symbolIndex]);
- offset += sizeof(uint32_t);
- }
-}
-
-template <typename P>
-void LinkeditOptimizer<P>::mergeLinkedits(Diagnostics& diagnostics,
- CacheBuilder::Region& readOnlyRegion,
- uint64_t nonLinkEditReadOnlySize,
- UnmappedLocalsOptimizer* localSymbolsOptimizer,
- DyldSharedCache::LocalSymbolsMode localSymbolMode,
- std::vector<LinkeditOptimizer<P>*>& optimizers)
-{
- // allocate space for new linkedit data
- uint64_t totalUnoptLinkeditsSize = readOnlyRegion.sizeInUse - nonLinkEditReadOnlySize;
- uint8_t* newLinkEdit = (uint8_t*)calloc(totalUnoptLinkeditsSize, 1);
- SortedStringPool stringPool;
- uint32_t offset = 0;
-
- diagnostics.verbose("Merged LINKEDIT:\n");
-
- // copy weak binding info
- uint32_t startWeakBindInfosOffset = offset;
- for (LinkeditOptimizer<P>* op : optimizers) {
- // Skip chained fixups as the in-place linked list isn't valid any more
- const dyld3::MachOFile* mf = (dyld3::MachOFile*)op->machHeader();
- if (!mf->hasChainedFixups())
- op->copyWeakBindingInfo(newLinkEdit, offset);
- }
- diagnostics.verbose(" weak bindings size: %5uKB\n", (uint32_t)(offset-startWeakBindInfosOffset)/1024);
-
- // copy export info
- uint32_t startExportInfosOffset = offset;
- for (LinkeditOptimizer<P>* op : optimizers) {
- op->copyExportInfo(newLinkEdit, offset);
- }
- diagnostics.verbose(" exports info size: %5uKB\n", (uint32_t)(offset-startExportInfosOffset)/1024);
-
- // in theory, an optimized cache can drop the binding info
- if ( true ) {
- // copy binding info
- uint32_t startBindingsInfosOffset = offset;
- for (LinkeditOptimizer<P>* op : optimizers) {
- // Skip chained fixups as the in-place linked list isn't valid any more
- const dyld3::MachOFile* mf = (dyld3::MachOFile*)op->machHeader();
- if (!mf->hasChainedFixups())
- op->copyBindingInfo(newLinkEdit, offset);
- }
- diagnostics.verbose(" bindings size: %5uKB\n", (uint32_t)(offset-startBindingsInfosOffset)/1024);
-
- // copy lazy binding info
- uint32_t startLazyBindingsInfosOffset = offset;
- for (LinkeditOptimizer<P>* op : optimizers) {
- // Skip chained fixups as the in-place linked list isn't valid any more
- const dyld3::MachOFile* mf = (dyld3::MachOFile*)op->machHeader();
- if (!mf->hasChainedFixups())
- op->copyLazyBindingInfo(newLinkEdit, offset);
- }
- diagnostics.verbose(" lazy bindings size: %5uKB\n", (offset-startLazyBindingsInfosOffset)/1024);
- }
-
- bool unmapLocals = ( localSymbolMode == DyldSharedCache::LocalSymbolsMode::unmap );
-
- uint32_t symbolIndex = 0;
- const uint32_t sharedSymbolTableStartOffset = offset;
- uint32_t sharedSymbolTableExportsCount = 0;
- uint32_t sharedSymbolTableImportsCount = 0;
- for (LinkeditOptimizer<P>* op : optimizers) {
- op->copyLocalSymbols(newLinkEdit, stringPool, offset, symbolIndex,
- unmapLocals ? localSymbolsOptimizer : nullptr);
- uint32_t x = symbolIndex;
- op->copyExportedSymbols(newLinkEdit, stringPool, offset, symbolIndex);
- sharedSymbolTableExportsCount += (symbolIndex-x);
- uint32_t y = symbolIndex;
- op->copyImportedSymbols(newLinkEdit, stringPool, offset, symbolIndex);
- sharedSymbolTableImportsCount += (symbolIndex-y);
- }
- uint32_t sharedSymbolTableCount = symbolIndex;
- const uint32_t sharedSymbolTableEndOffset = offset;
-
- // copy function starts
- uint32_t startFunctionStartsOffset = offset;
- for (LinkeditOptimizer<P>* op : optimizers) {
- op->copyFunctionStarts(newLinkEdit, offset);
- }
- diagnostics.verbose(" function starts size: %5uKB\n", (offset-startFunctionStartsOffset)/1024);
-
- // copy data-in-code info
- uint32_t startDataInCodeOffset = offset;
- for (LinkeditOptimizer<P>* op : optimizers) {
- op->copyDataInCode(newLinkEdit, offset);
- }
- diagnostics.verbose(" data in code size: %5uKB\n", (offset-startDataInCodeOffset)/1024);
-
- // copy indirect symbol tables
- for (LinkeditOptimizer<P>* op : optimizers) {
- op->copyIndirectSymbolTable(newLinkEdit, offset);
- }
- // if indirect table has odd number of entries, end will not be 8-byte aligned
- if ( (offset % sizeof(typename P::uint_t)) != 0 )
- offset += 4;
-
- // copy string pool
- uint32_t sharedSymbolStringsOffset = offset;
- uint32_t sharedSymbolStringsSize = stringPool.copyPoolAndUpdateOffsets((char*)&newLinkEdit[sharedSymbolStringsOffset], (macho_nlist<P>*)&newLinkEdit[sharedSymbolTableStartOffset]);
- offset += sharedSymbolStringsSize;
- uint32_t newLinkeditUnalignedSize = offset;
- uint64_t newLinkeditAlignedSize = align(offset, 14);
- diagnostics.verbose(" symbol table size: %5uKB (%d exports, %d imports)\n", (sharedSymbolTableEndOffset-sharedSymbolTableStartOffset)/1024, sharedSymbolTableExportsCount, sharedSymbolTableImportsCount);
- diagnostics.verbose(" symbol string pool size: %5uKB\n", sharedSymbolStringsSize/1024);
-
- // overwrite mapped LINKEDIT area in cache with new merged LINKEDIT content
- diagnostics.verbose("LINKEDITS optimized from %uMB to %uMB\n", (uint32_t)totalUnoptLinkeditsSize/(1024*1024), (uint32_t)newLinkeditUnalignedSize/(1024*1024));
- ::memcpy(readOnlyRegion.buffer + nonLinkEditReadOnlySize, newLinkEdit, newLinkeditAlignedSize);
- ::free(newLinkEdit);
- readOnlyRegion.sizeInUse = nonLinkEditReadOnlySize + newLinkeditAlignedSize;
-
- // update all load commands to new merged layout
- uint64_t linkeditsUnslidStartAddr = readOnlyRegion.unslidLoadAddress + nonLinkEditReadOnlySize;
- uint32_t linkeditsCacheFileOffset = (uint32_t)(readOnlyRegion.cacheFileOffset + nonLinkEditReadOnlySize);
- for (LinkeditOptimizer<P>* op : optimizers) {
- op->updateLoadCommands(linkeditsCacheFileOffset, linkeditsUnslidStartAddr, newLinkeditUnalignedSize,
- sharedSymbolTableStartOffset, sharedSymbolTableCount,
- sharedSymbolStringsOffset, sharedSymbolStringsSize);
- }
-}
-
-
-template <typename P>
-void LinkeditOptimizer<P>::optimizeLinkedit(Diagnostics& diagnostics,
- CacheBuilder::Region& readOnlyRegion,
- uint64_t nonLinkEditReadOnlySize,
- const void* containerBuffer,
- UnmappedLocalsOptimizer* localSymbolsOptimizer,
- DyldSharedCache::LocalSymbolsMode localSymbolMode,
- const std::vector<std::tuple<const mach_header*, const char*, DylibStripMode>>& images)
-{
- // construct a LinkeditOptimizer for each image
- __block std::vector<LinkeditOptimizer<P>*> optimizers;
- for (std::tuple<const mach_header*, const char*, DylibStripMode> image : images) {
- optimizers.push_back(new LinkeditOptimizer<P>(containerBuffer, (macho_header<P>*)std::get<0>(image), std::get<1>(image), diagnostics));
- optimizers.back()->setStripMode(std::get<2>(image));
- }
-#if 0
- // add optimizer for each branch pool
- for (uint64_t poolOffset : branchPoolOffsets) {
- macho_header<P>* mh = (macho_header<P>*)((char*)cache + poolOffset);
- optimizers.push_back(new LinkeditOptimizer<P>(cache, mh, diag));
- }
-#endif
- // merge linkedit info
- mergeLinkedits(diagnostics, readOnlyRegion, nonLinkEditReadOnlySize, localSymbolsOptimizer, localSymbolMode, optimizers);
-
- // delete optimizers
- for (LinkeditOptimizer<P>* op : optimizers)
- delete op;
-}
-
-void CacheBuilder::optimizeLinkedit(CacheBuilder::Region& readOnlyRegion,
- uint64_t nonLinkEditReadOnlySize,
- UnmappedLocalsOptimizer* localSymbolsOptimizer,
- const std::vector<std::tuple<const mach_header*, const char*, DylibStripMode>>& images)
-{
- const void* buffer = (const void*)_fullAllocatedBuffer;
- if ( _is64 ) {
- return LinkeditOptimizer<Pointer64<LittleEndian>>::optimizeLinkedit(_diagnostics,
- readOnlyRegion, nonLinkEditReadOnlySize,
- buffer,
- localSymbolsOptimizer, _options.localSymbolMode,
- images);
- }
- else {
- return LinkeditOptimizer<Pointer32<LittleEndian>>::optimizeLinkedit(_diagnostics,
- readOnlyRegion, nonLinkEditReadOnlySize,
- buffer,
- localSymbolsOptimizer, _options.localSymbolMode,
- images);
- }
-}