dyld/launch-cache/ObjCModernAbstraction.hpp

   1 /* -*- mode: C++; c-basic-offset: 4; tab-width: 4 -*-
   2  *
   3  * Copyright (c) 2008-2010 Apple Inc. All rights reserved.
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   7  * This file contains Original Code and/or Modifications of Original Code
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   9  * Version 2.0 (the 'License'). You may not use this file except in
  10  * compliance with the License. Please obtain a copy of the License at
  11  * http://www.opensource.apple.com/apsl/ and read it before using this
  12  * file.
  13  *
  14  * The Original Code and all software distributed under the License are
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  24
  25 #include "MachOLayout.hpp"
  26 #include <iterator>
  27 #include <deque>
  28
  29 // iterate an entsize-based list
  30 // typedef entsize_iterator< A, type_t<A>, type_list_t<A> > type_iterator;
  31 template <typename A, typename T, typename Tlist>
  32 struct entsize_iterator {
  33     uint32_t entsize;
  34     uint32_t index;  // keeping track of this saves a divide in operator-
  35     T* current;
  36
  37     typedef std::random_access_iterator_tag iterator_category;
  38     typedef T value_type;
  39     typedef ptrdiff_t difference_type;
  40     typedef T* pointer;
  41     typedef T& reference;
  42
  43     entsize_iterator() { }
  44
  45     entsize_iterator(const Tlist& list, uint32_t start = 0)
  46         : entsize(list.getEntsize()), index(start), current(&list.get(start))
  47     { }
  48
  49     const entsize_iterator<A,T,Tlist>& operator += (ptrdiff_t count) {
  50         current = (T*)((uint8_t *)current + count*entsize);
  51         index += count;
  52         return *this;
  53     }
  54     const entsize_iterator<A,T,Tlist>& operator -= (ptrdiff_t count) {
  55         current = (T*)((uint8_t *)current - count*entsize);
  56         index -= count;
  57         return *this;
  58     }
  59     const entsize_iterator<A,T,Tlist> operator + (ptrdiff_t count) const {
  60         return entsize_iterator(*this) += count;
  61     }
  62     const entsize_iterator<A,T,Tlist> operator - (ptrdiff_t count) const {
  63         return entsize_iterator(*this) -= count;
  64     }
  65
  66     entsize_iterator<A,T,Tlist>& operator ++ () { *this += 1; return *this; }
  67     entsize_iterator<A,T,Tlist>& operator -- () { *this -= 1; return *this; }
  68     entsize_iterator<A,T,Tlist> operator ++ (int) {
  69         entsize_iterator<A,T,Tlist> result(*this); *this += 1; return result;
  70     }
  71     entsize_iterator<A,T,Tlist> operator -- (int) {
  72         entsize_iterator<A,T,Tlist> result(*this); *this -= 1; return result;
  73     }
  74
  75     ptrdiff_t operator - (const entsize_iterator<A,T,Tlist>& rhs) const {
  76         return (ptrdiff_t)this->index - (ptrdiff_t)rhs.index;
  77     }
  78
  79     T& operator * () { return *current; }
  80     T& operator * () const { return *current; }
  81     T& operator -> () { return *current; }
  82     const T& operator -> () const { return *current; }
  83
  84     operator T& () const { return *current; }
  85
  86     bool operator == (const entsize_iterator<A,T,Tlist>& rhs) {
  87         return this->current == rhs.current;
  88     }
  89     bool operator != (const entsize_iterator<A,T,Tlist>& rhs) {
  90         return this->current != rhs.current;
  91     }
  92
  93     bool operator < (const entsize_iterator<A,T,Tlist>& rhs) {
  94         return this->current < rhs.current;
  95     }
  96     bool operator > (const entsize_iterator<A,T,Tlist>& rhs) {
  97         return this->current > rhs.current;
  98     }
  99
 100
 101     static void overwrite(entsize_iterator<A,T,Tlist>& dst, const Tlist* srcList)
 102     {
 103         entsize_iterator<A,T,Tlist> src;
 104         uint32_t ee = srcList->getEntsize();
 105         for (src = srcList->begin(); src != srcList->end(); ++src) {
 106             memcpy(&*dst, &*src, ee);
 107             ++dst;
 108         }
 109     }
 110 };
 111
 112 template <typename A>
 113 class objc_header_info_t {
 114
 115     typedef typename A::P P;
 116     typedef typename A::P::uint_t pint_t;
 117
 118     pint_t next;   // objc_header_info *
 119     pint_t mhdr;   // mach_header or mach_header_64
 120     pint_t info;   // objc_image_info *
 121     pint_t fname;  // const char *
 122     bool loaded;
 123     bool inSharedCache;
 124     bool allClassesRealized;
 125
 126 public:
 127     objc_header_info_t(SharedCache<A>* cache, const macho_header<P>* mh)
 128         : next(0),
 129           mhdr(0),
 130           info(0),
 131           fname(0),
 132           loaded(0),
 133           allClassesRealized(0)
 134     {
 135         A::P::setP(mhdr, cache->VMAddressForMappedAddress(mh));
 136         const macho_section<P>* sect = mh->getSection("__DATA", "__objc_imageinfo");
 137         if (sect) A::P::setP(info, sect->addr());
 138
 139         // can't set fname because dyld sometimes edits it
 140     }
 141
 142         void addPointers(std::vector<void*>& pointersToAdd) {
 143         pointersToAdd.push_back(&mhdr);
 144         if (info) pointersToAdd.push_back(&info);
 145     }
 146
 147     uint64_t header_vmaddr() const { return mhdr; }
 148 };
 149
 150 template <typename A> class objc_method_list_t;  // forward reference
 151
 152 template <typename A>
 153 class objc_method_t {
 154     typename A::P::uint_t name;   // SEL
 155     typename A::P::uint_t types;  // const char *
 156     typename A::P::uint_t imp;    // IMP
 157         friend class objc_method_list_t<A>;
 158 public:
 159     typename A::P::uint_t getName() const { return A::P::getP(name); }
 160     void setName(typename A::P::uint_t newName) { A::P::setP(name, newName); }
 161
 162     struct SortBySELAddress :
 163         public std::binary_function<const objc_method_t<A>&,
 164                                     const objc_method_t<A>&, bool>
 165     {
 166         bool operator() (const objc_method_t<A>& lhs,
 167                          const objc_method_t<A>& rhs)
 168         {
 169             return lhs.getName() < rhs.getName();
 170         }
 171     };
 172 };
 173
 174 template <typename A>
 175 class objc_method_list_t {
 176     uint32_t entsize;
 177     uint32_t count;
 178     objc_method_t<A> first;
 179
 180     void* operator new (size_t, void* buf) { return buf; }
 181
 182 public:
 183
 184     typedef entsize_iterator< A, objc_method_t<A>, objc_method_list_t<A> > method_iterator;
 185
 186     uint32_t getCount() const { return A::P::E::get32(count); }
 187
 188         uint32_t getEntsize() const {return A::P::E::get32(entsize)&~(uint32_t)3;}
 189
 190     objc_method_t<A>& get(uint32_t i) const { return *(objc_method_t<A> *)((uint8_t *)&first + i * getEntsize()); }
 191
 192     uint32_t byteSize() const {
 193         return byteSizeForCount(getCount(), getEntsize());
 194     }
 195
 196     static uint32_t byteSizeForCount(uint32_t c, uint32_t e = sizeof(objc_method_t<A>)) {
 197         return sizeof(objc_method_list_t<A>) - sizeof(objc_method_t<A>) + c*e;
 198     }
 199
 200     method_iterator begin() { return method_iterator(*this, 0); }
 201     method_iterator end() { return method_iterator(*this, getCount()); }
 202     const method_iterator begin() const { return method_iterator(*this, 0); }
 203     const method_iterator end() const { return method_iterator(*this, getCount()); }
 204
 205     void setFixedUp() { A::P::E::set32(entsize, getEntsize() | 3); }
 206
 207         void getPointers(std::set<void*>& pointersToRemove) {
 208                 for(method_iterator it = begin(); it != end(); ++it) {
 209                         objc_method_t<A>& entry = *it;
 210                         pointersToRemove.insert(&(entry.name));
 211                         pointersToRemove.insert(&(entry.types));
 212                         pointersToRemove.insert(&(entry.imp));
 213                 }
 214         }
 215
 216         static void addPointers(uint8_t* methodList, std::vector<void*>& pointersToAdd) {
 217                 objc_method_list_t<A>* mlist = (objc_method_list_t<A>*)methodList;
 218                 for(method_iterator it = mlist->begin(); it != mlist->end(); ++it) {
 219                         objc_method_t<A>& entry = *it;
 220                         pointersToAdd.push_back(&(entry.name));
 221                         pointersToAdd.push_back(&(entry.types));
 222                         pointersToAdd.push_back(&(entry.imp));
 223                 }
 224         }
 225
 226     static objc_method_list_t<A>* newMethodList(size_t newCount, uint32_t newEntsize) {
 227         void *buf = ::calloc(byteSizeForCount(newCount, newEntsize), 1);
 228         return new (buf) objc_method_list_t<A>(newCount, newEntsize);
 229     }
 230
 231     void operator delete(void * p) {
 232         ::free(p);
 233     }
 234
 235     objc_method_list_t(uint32_t newCount,
 236                        uint32_t newEntsize = sizeof(objc_method_t<A>))
 237         : entsize(newEntsize), count(newCount)
 238     { }
 239
 240 private:
 241     // use newMethodList instead
 242     void* operator new (size_t);
 243 };
 244
 245
 246 // Ivar offset variables are 64-bit on x86_64 and 32-bit everywhere else.
 247
 248 template <typename A>
 249 class objc_ivar_offset_t {
 250     typedef typename A::P::uint_t pint_t;
 251     typename A::P::uint_t ptr;  // uint32_t *
 252
 253     uint32_t& offset(SharedCache<A> *cache) const { return *(uint32_t *)cache->mappedAddressForVMAddress(A::P::getP(ptr)); }
 254
 255 public:
 256     bool hasOffset() const { return A::P::getP(ptr) != 0; }
 257     pint_t getOffset(SharedCache<A> *cache) const { return A::P::E::get32(offset(cache)); }
 258     void setOffset(SharedCache<A> *cache, pint_t newOffset) { A::P::E::set32(offset(cache), newOffset); }
 259 };
 260
 261 template <>
 262 class objc_ivar_offset_t<x86_64> {
 263     typedef x86_64 A;
 264     typedef typename A::P::uint_t pint_t;
 265     typename A::P::uint_t ptr;  // uint64_t *
 266
 267     uint64_t& offset(SharedCache<A> *cache) const { return *(uint64_t *)cache->mappedAddressForVMAddress(A::P::getP(ptr)); }
 268
 269 public:
 270     bool hasOffset() const { return A::P::getP(ptr) != 0; }
 271     pint_t getOffset(SharedCache<A> *cache) const { return A::P::E::get64(offset(cache)); }
 272     void setOffset(SharedCache<A> *cache, pint_t newOffset) { A::P::E::set64(offset(cache), newOffset); }
 273 };
 274
 275 template <typename A>
 276 class objc_ivar_t {
 277     typedef typename A::P::uint_t pint_t;
 278     objc_ivar_offset_t<A> offset;  // uint32_t *  (uint64_t * on x86_64)
 279     typename A::P::uint_t name;    // const char *
 280     typename A::P::uint_t type;    // const char *
 281     uint32_t alignment;
 282     uint32_t size;
 283
 284 public:
 285     const char * getName(SharedCache<A> *cache) const { return (const char *)cache->mappedAddressForVMAddress(A::P::getP(name)); }
 286
 287     bool hasOffset() const { return offset.hasOffset(); }
 288     pint_t getOffset(SharedCache<A> *cache) const { return offset.getOffset(cache); }
 289     void setOffset(SharedCache<A> *cache, pint_t newOffset) { offset.setOffset(cache, newOffset); }
 290
 291     uint32_t getAlignment()
 292     {
 293         uint32_t a = A::P::E::get32(alignment);
 294         return a == (uint32_t)-1 ? sizeof(typename A::P::uint_t) : 1<<a;
 295     }
 296 };
 297
 298 template <typename A>
 299 class objc_ivar_list_t {
 300     typedef typename A::P::uint_t pint_t;
 301     uint32_t entsize;
 302     uint32_t count;
 303     objc_ivar_t<A> first;
 304
 305     void* operator new (size_t, void* buf) { return buf; }
 306
 307 public:
 308
 309     typedef entsize_iterator< A, objc_ivar_t<A>, objc_ivar_list_t<A> > ivar_iterator;
 310
 311     uint32_t getCount() const { return A::P::E::get32(count); }
 312
 313         uint32_t getEntsize() const { return A::P::E::get32(entsize); }
 314
 315     objc_ivar_t<A>& get(pint_t i) const { return *(objc_ivar_t<A> *)((uint8_t *)&first + i * A::P::E::get32(entsize)); }
 316
 317     uint32_t byteSize() const {
 318         return byteSizeForCount(getCount(), getEntsize());
 319     }
 320
 321     static uint32_t byteSizeForCount(uint32_t c, uint32_t e = sizeof(objc_ivar_t<A>)) {
 322         return sizeof(objc_ivar_list_t<A>) - sizeof(objc_ivar_t<A>) + c*e;
 323     }
 324
 325     ivar_iterator begin() { return ivar_iterator(*this, 0); }
 326     ivar_iterator end() { return ivar_iterator(*this, getCount()); }
 327     const ivar_iterator begin() const { return ivar_iterator(*this, 0); }
 328     const ivar_iterator end() const { return ivar_iterator(*this, getCount()); }
 329
 330     static objc_ivar_list_t<A>* newIvarList(size_t newCount, uint32_t newEntsize) {
 331         void *buf = ::calloc(byteSizeForCount(newCount, newEntsize), 1);
 332         return new (buf) objc_ivar_list_t<A>(newCount, newEntsize);
 333     }
 334
 335     void operator delete(void * p) {
 336         ::free(p);
 337     }
 338
 339     objc_ivar_list_t(uint32_t newCount,
 340                          uint32_t newEntsize = sizeof(objc_ivar_t<A>))
 341         : entsize(newEntsize), count(newCount)
 342     { }
 343 private:
 344         // use newIvarList instead
 345     void* operator new (size_t);
 346 };
 347
 348
 349 template <typename A> class objc_property_list_t; // forward
 350
 351 template <typename A>
 352 class objc_property_t {
 353     typename A::P::uint_t name;
 354     typename A::P::uint_t attributes;
 355         friend class objc_property_list_t<A>;
 356 public:
 357
 358     const char * getName(SharedCache<A>* cache) const { return (const char *)cache->mappedAddressForVMAddress(A::P::getP(name)); }
 359
 360     const char * getAttributes(SharedCache<A>* cache) const { return (const char *)cache->mappedAddressForVMAddress(A::P::getP(attributes)); }
 361 };
 362
 363 template <typename A>
 364 class objc_property_list_t {
 365     uint32_t entsize;
 366     uint32_t count;
 367     objc_property_t<A> first;
 368
 369     void* operator new (size_t, void* buf) { return buf; }
 370
 371 public:
 372
 373     typedef entsize_iterator< A, objc_property_t<A>, objc_property_list_t<A> > property_iterator;
 374
 375     uint32_t getCount() const { return A::P::E::get32(count); }
 376
 377         uint32_t getEntsize() const { return A::P::E::get32(entsize); }
 378
 379     objc_property_t<A>& get(uint32_t i) const { return *(objc_property_t<A> *)((uint8_t *)&first + i * getEntsize()); }
 380
 381     uint32_t byteSize() const {
 382         return byteSizeForCount(getCount(), getEntsize());
 383     }
 384
 385     static uint32_t byteSizeForCount(uint32_t c, uint32_t e = sizeof(objc_property_t<A>)) {
 386         return sizeof(objc_property_list_t<A>) - sizeof(objc_property_t<A>) + c*e;
 387     }
 388
 389     property_iterator begin() { return property_iterator(*this, 0); }
 390     property_iterator end() { return property_iterator(*this, getCount()); }
 391     const property_iterator begin() const { return property_iterator(*this, 0); }
 392     const property_iterator end() const { return property_iterator(*this, getCount()); }
 393
 394         void getPointers(std::set<void*>& pointersToRemove) {
 395                 for(property_iterator it = begin(); it != end(); ++it) {
 396                         objc_property_t<A>& entry = *it;
 397                         pointersToRemove.insert(&(entry.name));
 398                         pointersToRemove.insert(&(entry.attributes));
 399                 }
 400         }
 401
 402         static void addPointers(uint8_t* propertyList, std::vector<void*>& pointersToAdd) {
 403                 objc_property_list_t<A>* plist = (objc_property_list_t<A>*)propertyList;
 404                 for(property_iterator it = plist->begin(); it != plist->end(); ++it) {
 405                         objc_property_t<A>& entry = *it;
 406                         pointersToAdd.push_back(&(entry.name));
 407                         pointersToAdd.push_back(&(entry.attributes));
 408                 }
 409         }
 410
 411      static objc_property_list_t<A>* newPropertyList(size_t newCount, uint32_t newEntsize) {
 412         void *buf = ::calloc(byteSizeForCount(newCount, newEntsize), 1);
 413         return new (buf) objc_property_list_t<A>(newCount, newEntsize);
 414     }
 415
 416     void operator delete(void * p) {
 417         ::free(p);
 418     }
 419
 420     objc_property_list_t(uint32_t newCount,
 421                          uint32_t newEntsize = sizeof(objc_property_t<A>))
 422         : entsize(newEntsize), count(newCount)
 423     { }
 424 private:
 425     // use newPropertyList instead
 426     void* operator new (size_t);
 427 };
 428
 429 template <typename A>
 430 class objc_protocol_t {
 431     typename A::P::uint_t isa;
 432     typename A::P::uint_t name;
 433     typename A::P::uint_t protocols;
 434     typename A::P::uint_t instanceMethods;
 435     typename A::P::uint_t classMethods;
 436     typename A::P::uint_t optionalInstanceMethods;
 437     typename A::P::uint_t optionalClassMethods;
 438     typename A::P::uint_t instanceProperties;
 439
 440 public:
 441     objc_method_list_t<A> *getInstanceMethods(SharedCache<A>* cache) const { return (objc_method_list_t<A> *)cache->mappedAddressForVMAddress(A::P::getP(instanceMethods)); }
 442
 443     objc_method_list_t<A> *getClassMethods(SharedCache<A>* cache) const { return (objc_method_list_t<A> *)cache->mappedAddressForVMAddress(A::P::getP(classMethods)); }
 444
 445     objc_method_list_t<A> *getOptionalInstanceMethods(SharedCache<A>* cache) const { return (objc_method_list_t<A> *)cache->mappedAddressForVMAddress(A::P::getP(optionalInstanceMethods)); }
 446
 447     objc_method_list_t<A> *getOptionalClassMethods(SharedCache<A>* cache) const { return (objc_method_list_t<A> *)cache->mappedAddressForVMAddress(A::P::getP(optionalClassMethods)); }
 448
 449 };
 450
 451 template <typename A>
 452 class objc_protocol_list_t {
 453     typedef typename A::P::uint_t pint_t;
 454     pint_t count;
 455     pint_t list[0];
 456
 457     void* operator new (size_t, void* buf) { return buf; }
 458
 459 public:
 460
 461     pint_t getCount() const { return A::P::getP(count); }
 462
 463     objc_protocol_t<A>* get(SharedCache<A>* cache, pint_t i) {
 464         return (objc_protocol_t<A>*)cache->mappedAddressForVMAddress(A::P::getP(list[i]));
 465     }
 466
 467     void overwrite(pint_t& index, const objc_protocol_list_t<A>* src) {
 468         pint_t srcCount = src->getCount();
 469         memcpy(list+index, src->list, srcCount * sizeof(pint_t));
 470         index += srcCount;
 471     }
 472
 473     uint32_t byteSize() const {
 474         return byteSizeForCount(getCount());
 475     }
 476     static uint32_t byteSizeForCount(pint_t c) {
 477         return sizeof(objc_protocol_list_t<A>) + c*sizeof(pint_t);
 478     }
 479
 480         void getPointers(std::set<void*>& pointersToRemove) {
 481                 for(int i=0 ; i < count; ++i) {
 482                         pointersToRemove.insert(&list[i]);
 483                 }
 484         }
 485
 486         static void addPointers(uint8_t* protocolList, std::vector<void*>& pointersToAdd) {
 487                 objc_protocol_list_t<A>* plist = (objc_protocol_list_t<A>*)protocolList;
 488                 for(int i=0 ; i < plist->count; ++i) {
 489                         pointersToAdd.push_back(&plist->list[i]);
 490                 }
 491         }
 492
 493     static objc_protocol_list_t<A>* newProtocolList(pint_t newCount) {
 494         void *buf = ::calloc(byteSizeForCount(newCount), 1);
 495         return new (buf) objc_protocol_list_t<A>(newCount);
 496     }
 497
 498     void operator delete(void * p) {
 499         ::free(p);
 500     }
 501
 502     objc_protocol_list_t(uint32_t newCount) : count(newCount) { }
 503 private:
 504     // use newProtocolList instead
 505     void* operator new (size_t);
 506 };
 507
 508
 509 template <typename A>
 510 class objc_class_data_t {
 511     uint32_t flags;
 512     uint32_t instanceStart;
 513     // Note there is 4-bytes of alignment padding between instanceSize and ivarLayout
 514     // on 64-bit archs, but no padding on 32-bit archs.
 515     // This union is a way to model that.
 516     union {
 517         uint32_t                instanceSize;
 518         typename A::P::uint_t   pad;
 519     } instanceSize;
 520     typename A::P::uint_t ivarLayout;
 521     typename A::P::uint_t name;
 522     typename A::P::uint_t baseMethods;
 523     typename A::P::uint_t baseProtocols;
 524     typename A::P::uint_t ivars;
 525     typename A::P::uint_t weakIvarLayout;
 526     typename A::P::uint_t baseProperties;
 527
 528 public:
 529     bool isMetaClass() { return A::P::E::get32(flags) & 1; }
 530
 531     uint32_t getInstanceStart() { return A::P::E::get32(instanceStart); }
 532     void setInstanceStart(uint32_t newStart) { A::P::E::set32(instanceStart, newStart); }
 533
 534     uint32_t getInstanceSize() { return A::P::E::get32(instanceSize.instanceSize); }
 535     void setInstanceSize(uint32_t newSiz) { A::P::E::set32(instanceSize.instanceSize, newSiz); }
 536
 537     objc_method_list_t<A> *getMethodList(SharedCache<A>* cache) const { return (objc_method_list_t<A> *)cache->mappedAddressForVMAddress(A::P::getP(baseMethods)); }
 538
 539     objc_protocol_list_t<A> *getProtocolList(SharedCache<A>* cache) const { return (objc_protocol_list_t<A> *)cache->mappedAddressForVMAddress(A::P::getP(baseProtocols)); }
 540
 541     objc_ivar_list_t<A> *getIvarList(SharedCache<A>* cache) const { return (objc_ivar_list_t<A> *)cache->mappedAddressForVMAddress(A::P::getP(ivars)); }
 542
 543     objc_property_list_t<A> *getPropertyList(SharedCache<A>* cache) const { return (objc_property_list_t<A> *)cache->mappedAddressForVMAddress(A::P::getP(baseProperties)); }
 544
 545     const char * getName(SharedCache<A>* cache) const { return (const char *)cache->mappedAddressForVMAddress(A::P::getP(name)); }
 546
 547     void setMethodList(SharedCache<A>* cache, objc_method_list_t<A>* mlist) {
 548         A::P::setP(baseMethods, cache->VMAddressForMappedAddress(mlist));
 549     }
 550
 551     void setProtocolList(SharedCache<A>* cache, objc_protocol_list_t<A>* protolist) {
 552         A::P::setP(baseProtocols, cache->VMAddressForMappedAddress(protolist));
 553     }
 554
 555     void setPropertyList(SharedCache<A>* cache, objc_property_list_t<A>* proplist) {
 556         A::P::setP(baseProperties, cache->VMAddressForMappedAddress(proplist));
 557     }
 558
 559         void addMethodListPointer(std::vector<void*>& pointersToAdd) {
 560                 pointersToAdd.push_back(&this->baseMethods);
 561         }
 562
 563         void addPropertyListPointer(std::vector<void*>& pointersToAdd) {
 564                 pointersToAdd.push_back(&this->baseProperties);
 565         }
 566
 567         void addProtocolListPointer(std::vector<void*>& pointersToAdd) {
 568                 pointersToAdd.push_back(&this->baseProtocols);
 569         }
 570 };
 571
 572 template <typename A>
 573 class objc_class_t {
 574     typename A::P::uint_t isa;
 575     typename A::P::uint_t superclass;
 576     typename A::P::uint_t method_cache;
 577     typename A::P::uint_t vtable;
 578     typename A::P::uint_t data;
 579
 580 public:
 581     bool isMetaClass(SharedCache<A>* cache) const { return getData(cache)->isMetaClass(); }
 582
 583     objc_class_t<A> *getIsa(SharedCache<A> *cache) const { return (objc_class_t<A> *)cache->mappedAddressForVMAddress(A::P::getP(isa)); }
 584
 585     objc_class_t<A> *getSuperclass(SharedCache<A> *cache) const { return (objc_class_t<A> *)cache->mappedAddressForVMAddress(A::P::getP(superclass)); }
 586
 587     objc_class_data_t<A> *getData(SharedCache<A>* cache) const { return (objc_class_data_t<A> *)cache->mappedAddressForVMAddress(A::P::getP(data)); }
 588
 589     objc_method_list_t<A> *getMethodList(SharedCache<A>* cache) const { return getData(cache)->getMethodList(cache); }
 590
 591     objc_protocol_list_t<A> *getProtocolList(SharedCache<A>* cache) const { return getData(cache)->getProtocolList(cache); }
 592
 593     objc_property_list_t<A> *getPropertyList(SharedCache<A>* cache) const { return getData(cache)->getPropertyList(cache); }
 594
 595     const char * getName(SharedCache<A>* cache) const {
 596         return getData(cache)->getName(cache);
 597     }
 598
 599     void setMethodList(SharedCache<A>* cache, objc_method_list_t<A>* mlist) {
 600         getData(cache)->setMethodList(cache, mlist);
 601     }
 602
 603     void setProtocolList(SharedCache<A>* cache, objc_protocol_list_t<A>* protolist) {
 604         getData(cache)->setProtocolList(cache, protolist);
 605     }
 606
 607     void setPropertyList(SharedCache<A>* cache, objc_property_list_t<A>* proplist) {
 608         getData(cache)->setPropertyList(cache, proplist);
 609     }
 610
 611         void addMethodListPointer(SharedCache<A>* cache, std::vector<void*>& pointersToAdd) {
 612         getData(cache)->addMethodListPointer(pointersToAdd);
 613         }
 614
 615         void addPropertyListPointer(SharedCache<A>* cache, std::vector<void*>& pointersToAdd) {
 616         getData(cache)->addPropertyListPointer(pointersToAdd);
 617         }
 618
 619         void addProtocolListPointer(SharedCache<A>* cache, std::vector<void*>& pointersToAdd) {
 620         getData(cache)->addProtocolListPointer(pointersToAdd);
 621         }
 622
 623 };
 624
 625
 626
 627 template <typename A>
 628 class objc_category_t {
 629     typename A::P::uint_t name;
 630     typename A::P::uint_t cls;
 631     typename A::P::uint_t instanceMethods;
 632     typename A::P::uint_t classMethods;
 633     typename A::P::uint_t protocols;
 634     typename A::P::uint_t instanceProperties;
 635
 636 public:
 637
 638     const char * getName(SharedCache<A> *cache) const { return (const char *)cache->mappedAddressForVMAddress(A::P::getP(name)); }
 639
 640     objc_class_t<A> *getClass(SharedCache<A> *cache) const { return (objc_class_t<A> *)cache->mappedAddressForVMAddress(A::P::getP(cls)); }
 641
 642     objc_method_list_t<A> *getInstanceMethods(SharedCache<A>* cache) const { return (objc_method_list_t<A> *)cache->mappedAddressForVMAddress(A::P::getP(instanceMethods)); }
 643
 644     objc_method_list_t<A> *getClassMethods(SharedCache<A>* cache) const { return (objc_method_list_t<A> *)cache->mappedAddressForVMAddress(A::P::getP(classMethods)); }
 645
 646     objc_protocol_list_t<A> *getProtocols(SharedCache<A>* cache) const { return (objc_protocol_list_t<A> *)cache->mappedAddressForVMAddress(A::P::getP(protocols)); }
 647
 648     objc_property_list_t<A> *getInstanceProperties(SharedCache<A>* cache) const { return (objc_property_list_t<A> *)cache->mappedAddressForVMAddress(A::P::getP(instanceProperties)); }
 649
 650         void getPointers(std::set<void*>& pointersToRemove) {
 651                 pointersToRemove.insert(&name);
 652                 pointersToRemove.insert(&cls);
 653                 pointersToRemove.insert(&instanceMethods);
 654                 pointersToRemove.insert(&classMethods);
 655                 pointersToRemove.insert(&protocols);
 656                 pointersToRemove.insert(&instanceProperties);
 657         }
 658
 659
 660 };
 661
 662 template <typename A>
 663 class objc_message_ref_t {
 664     typename A::P::uint_t imp;
 665     typename A::P::uint_t sel;
 666
 667 public:
 668     typename A::P::uint_t getName() const { return A::P::getP(sel); }
 669
 670     void setName(typename A::P::uint_t newName) { A::P::setP(sel, newName); }
 671 };
 672
 673 // Call visitor.visitIvar() on every ivar in a given class.
 674 template <typename A, typename V>
 675 class IvarWalker {
 676     typedef typename A::P P;
 677     typedef typename A::P::uint_t pint_t;
 678     V& ivarVisitor;
 679 public:
 680
 681     IvarWalker(V& visitor) : ivarVisitor(visitor) { }
 682
 683     void walk(SharedCache<A>* cache, const macho_header<P>* header, objc_class_t<A> *cls)
 684     {
 685         objc_class_data_t<A> *data = cls->getData(cache);
 686         objc_ivar_list_t<A> *ivars = data->getIvarList(cache);
 687         if (ivars) {
 688             for (pint_t i = 0; i < ivars->getCount(); i++) {
 689                 objc_ivar_t<A>& ivar = ivars->get(i);
 690                 //fprintf(stderr, "visiting ivar: %s\n", ivar.getName(cache));
 691                 ivarVisitor.visitIvar(cache, header, cls, &ivar);
 692             }
 693         } else {
 694             //fprintf(stderr, "no ivars\n");
 695         }
 696     }
 697
 698     void visitClass(SharedCache<A>* cache, const macho_header<P>* header, objc_class_t<A> *cls)
 699     {
 700         walk(cache, header, cls);
 701     }
 702 };
 703
 704 // Call visitor.visitClass() on every class.
 705 template <typename A, typename V>
 706 class ClassWalker {
 707     typedef typename A::P P;
 708     typedef typename A::P::uint_t pint_t;
 709     V& classVisitor;
 710 public:
 711
 712     ClassWalker(V& visitor) : classVisitor(visitor) { }
 713
 714     void walk(SharedCache<A>* cache, const macho_header<P>* header)
 715     {
 716         PointerSection<A, objc_class_t<A> *>
 717         classes(cache, header, "__DATA", "__objc_classlist");
 718
 719         for (pint_t i = 0; i < classes.count(); i++) {
 720             objc_class_t<A> *cls = classes.get(i);
 721             //fprintf(stderr, "visiting class: %s\n", cls->getName(cache));
 722             classVisitor.visitClass(cache, header, cls);
 723         }
 724     }
 725 };
 726
 727
 728 // Call visitor.visitMethodList(mlist) on every method list in a header.
 729 template <typename A, typename V>
 730 class MethodListWalker {
 731
 732     typedef typename A::P P;
 733     typedef typename A::P::uint_t pint_t;
 734
 735     V& mVisitor;
 736
 737 public:
 738
 739     MethodListWalker(V& visitor) : mVisitor(visitor) { }
 740
 741     void walk(SharedCache<A>* cache, const macho_header<P>* header, bool walkProtocols)
 742     {
 743         // Method lists in classes
 744         PointerSection<A, objc_class_t<A> *>
 745             classes(cache, header, "__DATA", "__objc_classlist");
 746
 747         for (pint_t i = 0; i < classes.count(); i++) {
 748             objc_class_t<A> *cls = classes.get(i);
 749             objc_method_list_t<A> *mlist;
 750             if ((mlist = cls->getMethodList(cache))) {
 751                 mVisitor.visitMethodList(mlist);
 752             }
 753             if ((mlist = cls->getIsa(cache)->getMethodList(cache))) {
 754                 mVisitor.visitMethodList(mlist);
 755             }
 756         }
 757
 758         // Method lists from categories
 759         PointerSection<A, objc_category_t<A> *>
 760             cats(cache, header, "__DATA", "__objc_catlist");
 761         for (pint_t i = 0; i < cats.count(); i++) {
 762             objc_category_t<A> *cat = cats.get(i);
 763             objc_method_list_t<A> *mlist;
 764             if ((mlist = cat->getInstanceMethods(cache))) {
 765                 mVisitor.visitMethodList(mlist);
 766             }
 767             if ((mlist = cat->getClassMethods(cache))) {
 768                 mVisitor.visitMethodList(mlist);
 769             }
 770         }
 771
 772                 // Method description lists from protocols
 773                 if ( walkProtocols ) {
 774                         PointerSection<A, objc_protocol_t<A> *>
 775                                 protocols(cache, header, "__DATA", "__objc_protolist");
 776                         for (pint_t i = 0; i < protocols.count(); i++) {
 777                                 objc_protocol_t<A> *proto = protocols.get(i);
 778                                 objc_method_list_t<A> *mlist;
 779                                 if ((mlist = proto->getInstanceMethods(cache))) {
 780                                         mVisitor.visitMethodList(mlist);
 781                                 }
 782                                 if ((mlist = proto->getClassMethods(cache))) {
 783                                         mVisitor.visitMethodList(mlist);
 784                                 }
 785                                 if ((mlist = proto->getOptionalInstanceMethods(cache))) {
 786                                         mVisitor.visitMethodList(mlist);
 787                                 }
 788                                 if ((mlist = proto->getOptionalClassMethods(cache))) {
 789                                         mVisitor.visitMethodList(mlist);
 790                                 }
 791                         }
 792                 }
 793     }
 794 };
 795
 796
 797 // Update selector references. The visitor performs recording and uniquing.
 798 template <typename A, typename V>
 799 class SelectorOptimizer {
 800
 801     typedef typename A::P P;
 802     typedef typename A::P::uint_t pint_t;
 803
 804     V& mVisitor;
 805
 806     friend class MethodListWalker< A, SelectorOptimizer<A,V> >;
 807     void visitMethodList(objc_method_list_t<A> *mlist)
 808     {
 809         // Gather selectors. Update method names.
 810         for (pint_t m = 0; m < mlist->getCount(); m++) {
 811             pint_t oldValue = mlist->get(m).getName();
 812             pint_t newValue = mVisitor.visit(oldValue);
 813             mlist->get(m).setName(newValue);
 814         }
 815         // Do not setFixedUp: the methods are not yet sorted.
 816     }
 817
 818 public:
 819
 820     SelectorOptimizer(V& visitor) : mVisitor(visitor) { }
 821
 822     void optimize(SharedCache<A>* cache, const macho_header<P>* header)
 823     {
 824         // method lists of all kinds
 825         MethodListWalker< A, SelectorOptimizer<A,V> > mw(*this);
 826         mw.walk(cache, header, true);
 827
 828         // @selector references
 829         PointerSection<A, const char *>
 830             selrefs(cache, header, "__DATA", "__objc_selrefs");
 831         for (pint_t i = 0; i < selrefs.count(); i++) {
 832             pint_t oldValue = selrefs.getUnmapped(i);
 833             pint_t newValue = mVisitor.visit(oldValue);
 834             selrefs.set(i, newValue);
 835         }
 836
 837         // message references
 838         ArraySection<A, objc_message_ref_t<A> >
 839             msgrefs(cache, header, "__DATA", "__objc_msgrefs");
 840         for (pint_t i = 0; i < msgrefs.count(); i++) {
 841             objc_message_ref_t<A>& msg = msgrefs.get(i);
 842             pint_t oldValue = msg.getName();
 843             pint_t newValue = mVisitor.visit(oldValue);
 844             msg.setName(newValue);
 845         }
 846     }
 847 };
 848
 849
 850 // Update selector references. The visitor performs recording and uniquing.
 851 template <typename A>
 852 class IvarOffsetOptimizer {
 853     typedef typename A::P P;
 854
 855     uint32_t slide;
 856     uint32_t maxAlignment;
 857
 858     uint32_t fOptimized;
 859
 860 public:
 861
 862     IvarOffsetOptimizer() : fOptimized(0) { }
 863
 864     size_t optimized() const { return fOptimized; }
 865
 866     // dual purpose ivar visitor function
 867     // if slide!=0 then slides the ivar by that amount, otherwise computes maxAlignment
 868     void visitIvar(SharedCache<A>* cache, const macho_header<P>* /*unused, may be NULL*/, objc_class_t<A> *cls, objc_ivar_t<A> *ivar)
 869     {
 870         if (slide == 0) {
 871             uint32_t alignment = ivar->getAlignment();
 872             if (alignment > maxAlignment) maxAlignment = alignment;
 873         } else {
 874             // skip anonymous bitfields
 875             if (ivar->hasOffset()) {
 876                 uint32_t oldOffset = (uint32_t)ivar->getOffset(cache);
 877                 ivar->setOffset(cache, oldOffset + slide);
 878                 fOptimized++;
 879                 //fprintf(stderr, "%d -> %d for %s.%s\n", oldOffset, oldOffset + slide, cls->getName(cache), ivar->getName(cache));
 880             } else {
 881                 //fprintf(stderr, "NULL offset\n");
 882             }
 883         }
 884     }
 885
 886     // Class visitor function. Evaluates whether to slide ivars and performs slide if needed.
 887     // The slide algorithm is also implemented in objc. Any changes here should be reflected there also.
 888     void visitClass(SharedCache<A>* cache, const macho_header<P>* /*unused, may be NULL*/, objc_class_t<A> *cls)
 889     {
 890         objc_class_t<A> *super = cls->getSuperclass(cache);
 891         if (super) {
 892             // Recursively visit superclasses to ensure we have the correct superclass start
 893             // Note that we don't need the macho_header, so just pass NULL.
 894             visitClass(cache, NULL, super);
 895
 896             objc_class_data_t<A> *data = cls->getData(cache);
 897             objc_class_data_t<A> *super_data = super->getData(cache);
 898             int32_t diff = super_data->getInstanceSize() - data->getInstanceStart();
 899             if (diff > 0) {
 900                 IvarWalker<A, IvarOffsetOptimizer<A> > ivarVisitor(*this);
 901                 maxAlignment = 0;
 902                 slide = 0;
 903
 904                 // This walk computes maxAlignment
 905                 ivarVisitor.walk(cache, NULL, cls);
 906
 907                 // Compute a slide value that preserves that alignment
 908                 uint32_t alignMask = maxAlignment - 1;
 909                 if (diff & alignMask) diff = (diff + alignMask) & ~alignMask;
 910
 911                 // Slide all of this class's ivars en masse
 912                 slide = diff;
 913                 if (slide != 0) {
 914                     //fprintf(stderr, "Sliding ivars in %s by %u (superclass was %d, now %d)\n", cls->getName(cache), slide, data->getInstanceStart(), super_data->getInstanceSize());
 915                     ivarVisitor.walk(cache, NULL, cls);
 916                     data->setInstanceStart(data->getInstanceStart() + slide);
 917                     data->setInstanceSize(data->getInstanceSize() + slide);
 918                 }
 919             }
 920         }
 921     }
 922
 923     // Enumerates objc classes in the module and performs any ivar slides
 924     void optimize(SharedCache<A>* cache, const macho_header<P>* header)
 925     {
 926         // The slide code cannot fix up GC layout strings so skip modules that support ore require GC
 927         const macho_section<P> *imageInfoSection = header->getSection("__DATA", "__objc_imageinfo");
 928         if (imageInfoSection) {
 929             objc_image_info<A> *info = (objc_image_info<A> *)cache->mappedAddressForVMAddress(imageInfoSection->addr());
 930             if (!info->supportsGCFlagSet() && !info->requiresGCFlagSet()) {
 931                 ClassWalker<A, IvarOffsetOptimizer<A> > classVisitor(*this);
 932                 classVisitor.walk(cache, header);
 933             } else {
 934                 //fprintf(stderr, "GC support present - skipped module\n");
 935             }
 936         }
 937     }
 938 };
 939
 940
 941 // Sort methods in place by selector.
 942 template <typename A>
 943 class MethodListSorter {
 944
 945     typedef typename A::P P;
 946     typedef typename A::P::uint_t pint_t;
 947
 948     uint32_t fOptimized;
 949
 950     friend class MethodListWalker<A, MethodListSorter<A> >;
 951     void visitMethodList(objc_method_list_t<A> *mlist)
 952     {
 953         typename objc_method_t<A>::SortBySELAddress sorter;
 954         std::stable_sort(mlist->begin(), mlist->end(), sorter);
 955         mlist->setFixedUp();
 956         fOptimized++;
 957     }
 958
 959 public:
 960     MethodListSorter() : fOptimized(0) { }
 961
 962     size_t optimized() const { return fOptimized; }
 963
 964     void optimize(SharedCache<A>* cache, macho_header<P>* header)
 965     {
 966         MethodListWalker<A, MethodListSorter<A> > mw(*this);
 967         mw.walk(cache, header, false /* don't sort protocol method lists*/);
 968     }
 969 };
 970
 971
 972 template <typename A>
 973 class HeaderInfoOptimizer {
 974
 975     typedef typename A::P P;
 976     typedef typename A::P::uint_t pint_t;
 977
 978     objc_header_info_t<A>* fHinfos;
 979     size_t fCount;
 980
 981 public:
 982     HeaderInfoOptimizer() : fHinfos(0), fCount(0) { }
 983
 984     const char *init(size_t count, uint8_t*& buf, size_t& bufSize)
 985     {
 986         if (count == 0) return NULL;
 987
 988         if (bufSize < 2*sizeof(uint32_t) + count*sizeof(objc_header_info_t<A>)) {
 989             return "libobjc's read/write section is too small (metadata not optimized)";
 990         }
 991
 992         uint32_t *buf32 = (uint32_t *)buf;
 993         A::P::E::set32(buf32[0], count);
 994         A::P::E::set32(buf32[1], sizeof(objc_header_info_t<A>));
 995         fHinfos = (objc_header_info_t<A>*)(buf32+2);
 996
 997         size_t total = sizeof(uint32_t) + count*sizeof(objc_header_info_t<A>);
 998         buf += total;
 999         bufSize -= total;
1000
1001         return NULL;
1002     }
1003
1004     void update(SharedCache<A>* cache, const macho_header<P>* mh, std::vector<void*>& pointersInData)
1005     {
1006         objc_header_info_t<A>* hi = new(&fHinfos[fCount++]) objc_header_info_t<A>(cache, mh);
1007         hi->addPointers(pointersInData);
1008     }
1009
1010     objc_header_info_t<A>* hinfoForHeader(SharedCache<A>* cache, const macho_header<P>* mh)
1011     {
1012         // fixme could be binary search
1013         pint_t mh_vmaddr = cache->VMAddressForMappedAddress(mh);
1014         for (size_t i = 0; i < fCount; i++) {
1015             objc_header_info_t<A>* hi = &fHinfos[i];
1016             if (hi->header_vmaddr() == mh_vmaddr) return hi;
1017         }
1018         return NULL;
1019     }
1020 };