src/mc/remote/RemoteClient.cpp

   1 /* Copyright (c) 2014-2018. The SimGrid Team. All rights reserved.          */
   2
   3 /* This program is free software; you can redistribute it and/or modify it
   4  * under the terms of the license (GNU LGPL) which comes with this package. */
   5
   6 #define _FILE_OFFSET_BITS 64 /* needed for pread_whole to work as expected on 32bits */
   7
   8 #include <algorithm>
   9 #include <cassert>
  10 #include <cerrno>
  11 #include <cstddef>
  12 #include <cstdint>
  13 #include <string>
  14 #include <vector>
  15
  16 #include <sys/ptrace.h>
  17
  18 #include <cstdio>
  19
  20 #include <fcntl.h>
  21 #include <sys/mman.h> // PROT_*
  22 #include <sys/types.h>
  23 #include <unistd.h>
  24
  25 #include <pthread.h>
  26
  27 #include <libgen.h>
  28
  29 #include <libunwind-ptrace.h>
  30 #include <libunwind.h>
  31
  32 #include "xbt/base.h"
  33 #include "xbt/file.hpp"
  34 #include "xbt/log.h"
  35 #include <xbt/mmalloc.h>
  36
  37 #include "src/mc/mc_smx.hpp"
  38 #include "src/mc/mc_unw.hpp"
  39 #include "src/mc/sosp/mc_snapshot.hpp"
  40
  41 #include "src/mc/AddressSpace.hpp"
  42 #include "src/mc/ObjectInformation.hpp"
  43 #include "src/mc/Variable.hpp"
  44 #include "src/mc/remote/RemoteClient.hpp"
  45
  46 using simgrid::mc::remote;
  47
  48 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_process, mc, "MC process information");
  49
  50 namespace simgrid {
  51 namespace mc {
  52
  53 // ***** Helper stuff
  54
  55 // List of library which memory segments are not considered:
  56 static const std::vector<std::string> filtered_libraries = {
  57 #ifdef __linux__
  58     "ld",
  59 #elif defined __FreeBSD__
  60     "ld-elf",
  61     "ld-elf32",
  62     "libkvm",      /* kernel data access library */
  63     "libprocstat", /* process and file information retrieval */
  64     "libthr",      /* thread library */
  65     "libutil",
  66 #endif
  67     "libargp", /* workarounds for glibc-less systems */
  68     "libasan", /* gcc sanitizers */
  69     "libboost_chrono",
  70     "libboost_context",
  71     "libboost_context-mt",
  72     "libboost_stacktrace_backtrace",
  73     "libboost_system",
  74     "libboost_thread",
  75     "libboost_timer",
  76     "libboost_unit_test_framework",
  77     "libbz2",
  78     "libc",
  79     "libc++",
  80     "libcdt",
  81     "libcgraph",
  82     "libcrypto",
  83     "libcxxrt",
  84     "libdl",
  85     "libdw",
  86     "libelf",
  87     "libevent",
  88     "libexecinfo",
  89     "libflang",
  90     "libflangrti",
  91     "libgcc_s",
  92     "libgfortran",
  93     "libimf",
  94     "libintlc",
  95     "libirng",
  96     "liblua5.1",
  97     "liblua5.3",
  98     "liblzma",
  99     "libm",
 100     "libomp",
 101     "libpapi",
 102     "libpfm",
 103     "libpthread",
 104     "libquadmath",
 105     "librt",
 106     "libstdc++",
 107     "libsvml",
 108     "libtsan",  /* gcc sanitizers */
 109     "libubsan", /* gcc sanitizers */
 110     "libunwind",
 111     "libunwind-ptrace",
 112     "libunwind-x86",
 113     "libunwind-x86_64",
 114     "libz"};
 115
 116 static bool is_simgrid_lib(const std::string& libname)
 117 {
 118   return libname == "libsimgrid";
 119 }
 120
 121 static bool is_filtered_lib(const std::string& libname)
 122 {
 123   return std::find(begin(filtered_libraries), end(filtered_libraries), libname) != end(filtered_libraries);
 124 }
 125
 126 static std::string get_lib_name(const std::string& pathname)
 127 {
 128   std::string map_basename = simgrid::xbt::Path(pathname).get_base_name();
 129   std::string libname;
 130
 131   size_t pos = map_basename.rfind(".so");
 132   if (pos != std::string::npos) {
 133     // strip the extension (matching regex "\.so.*$")
 134     libname.assign(map_basename, 0, pos);
 135
 136     // strip the version suffix (matching regex "-[.0-9-]*$")
 137     while (true) {
 138       pos = libname.rfind('-');
 139       if (pos == std::string::npos || libname.find_first_not_of(".0123456789", pos + 1) != std::string::npos)
 140         break;
 141       libname.erase(pos);
 142     }
 143   }
 144
 145   return libname;
 146 }
 147
 148 static ssize_t pread_whole(int fd, void* buf, size_t count, off_t offset)
 149 {
 150   char* buffer       = (char*)buf;
 151   ssize_t real_count = count;
 152   while (count) {
 153     ssize_t res = pread(fd, buffer, count, offset);
 154     if (res > 0) {
 155       count -= res;
 156       buffer += res;
 157       offset += res;
 158     } else if (res == 0)
 159       return -1;
 160     else if (errno != EINTR) {
 161       perror("pread_whole");
 162       return -1;
 163     }
 164   }
 165   return real_count;
 166 }
 167
 168 static ssize_t pwrite_whole(int fd, const void* buf, size_t count, off_t offset)
 169 {
 170   const char* buffer = (const char*)buf;
 171   ssize_t real_count = count;
 172   while (count) {
 173     ssize_t res = pwrite(fd, buffer, count, offset);
 174     if (res > 0) {
 175       count -= res;
 176       buffer += res;
 177       offset += res;
 178     } else if (res == 0)
 179       return -1;
 180     else if (errno != EINTR)
 181       return -1;
 182   }
 183   return real_count;
 184 }
 185
 186 static pthread_once_t zero_buffer_flag = PTHREAD_ONCE_INIT;
 187 static const void* zero_buffer;
 188 static const size_t zero_buffer_size = 10 * 4096;
 189
 190 static void zero_buffer_init()
 191 {
 192   int fd = open("/dev/zero", O_RDONLY);
 193   if (fd < 0)
 194     xbt_die("Could not open /dev/zero");
 195   zero_buffer = mmap(nullptr, zero_buffer_size, PROT_READ, MAP_SHARED, fd, 0);
 196   if (zero_buffer == MAP_FAILED)
 197     xbt_die("Could not map the zero buffer");
 198   close(fd);
 199 }
 200
 201 int open_vm(pid_t pid, int flags)
 202 {
 203   const size_t buffer_size = 30;
 204   char buffer[buffer_size];
 205   int res = snprintf(buffer, buffer_size, "/proc/%lli/mem", (long long)pid);
 206   if (res < 0 || (size_t)res >= buffer_size) {
 207     errno = ENAMETOOLONG;
 208     return -1;
 209   }
 210   return open(buffer, flags);
 211 }
 212
 213 // ***** Process
 214
 215 RemoteClient::RemoteClient(pid_t pid, int sockfd) : AddressSpace(this), pid_(pid), channel_(sockfd), running_(true)
 216 {
 217 }
 218
 219 void RemoteClient::init()
 220 {
 221   this->memory_map_ = simgrid::xbt::get_memory_map(this->pid_);
 222   this->init_memory_map_info();
 223
 224   int fd = open_vm(this->pid_, O_RDWR);
 225   if (fd < 0)
 226     xbt_die("Could not open file for process virtual address space");
 227   this->memory_file = fd;
 228
 229   // Read std_heap (is a struct mdesc*):
 230   simgrid::mc::Variable* std_heap_var = this->find_variable("__mmalloc_default_mdp");
 231   if (not std_heap_var)
 232     xbt_die("No heap information in the target process");
 233   if (not std_heap_var->address)
 234     xbt_die("No constant address for this variable");
 235   this->read_bytes(&this->heap_address, sizeof(mdesc*), remote(std_heap_var->address),
 236                    simgrid::mc::ProcessIndexDisabled);
 237
 238   this->smx_actors_infos.clear();
 239   this->smx_dead_actors_infos.clear();
 240   this->unw_addr_space            = simgrid::mc::UnwindContext::createUnwindAddressSpace();
 241   this->unw_underlying_addr_space = simgrid::unw::create_addr_space();
 242   this->unw_underlying_context    = simgrid::unw::create_context(this->unw_underlying_addr_space, this->pid_);
 243 }
 244
 245 RemoteClient::~RemoteClient()
 246 {
 247   if (this->memory_file >= 0)
 248     close(this->memory_file);
 249
 250   if (this->unw_underlying_addr_space != unw_local_addr_space) {
 251     if (this->unw_underlying_addr_space)
 252       unw_destroy_addr_space(this->unw_underlying_addr_space);
 253     if (this->unw_underlying_context)
 254       _UPT_destroy(this->unw_underlying_context);
 255   }
 256
 257   unw_destroy_addr_space(this->unw_addr_space);
 258 }
 259
 260 /** Refresh the information about the process
 261  *
 262  *  Do not use directly, this is used by the getters when appropriate
 263  *  in order to have fresh data.
 264  */
 265 void RemoteClient::refresh_heap()
 266 {
 267   // Read/dereference/refresh the std_heap pointer:
 268   if (not this->heap)
 269     this->heap = std::unique_ptr<s_xbt_mheap_t>(new s_xbt_mheap_t());
 270   this->read_bytes(this->heap.get(), sizeof(mdesc), remote(this->heap_address), simgrid::mc::ProcessIndexDisabled);
 271   this->cache_flags_ |= RemoteClient::cache_heap;
 272 }
 273
 274 /** Refresh the information about the process
 275  *
 276  *  Do not use direclty, this is used by the getters when appropriate
 277  *  in order to have fresh data.
 278  * */
 279 void RemoteClient::refresh_malloc_info()
 280 {
 281   // Refresh process->heapinfo:
 282   if (this->cache_flags_ & RemoteClient::cache_malloc)
 283     return;
 284   size_t count = this->heap->heaplimit + 1;
 285   if (this->heap_info.size() < count)
 286     this->heap_info.resize(count);
 287   this->read_bytes(this->heap_info.data(), count * sizeof(malloc_info), remote(this->heap->heapinfo),
 288                    simgrid::mc::ProcessIndexDisabled);
 289   this->cache_flags_ |= RemoteClient::cache_malloc;
 290 }
 291
 292 /** @brief Finds the range of the different memory segments and binary paths */
 293 void RemoteClient::init_memory_map_info()
 294 {
 295   XBT_DEBUG("Get debug information ...");
 296   this->maestro_stack_start_ = nullptr;
 297   this->maestro_stack_end_   = nullptr;
 298   this->object_infos.resize(0);
 299   this->binary_info     = nullptr;
 300   this->libsimgrid_info = nullptr;
 301
 302   std::vector<simgrid::xbt::VmMap> const& maps = this->memory_map_;
 303
 304   const char* current_name = nullptr;
 305
 306   this->object_infos.clear();
 307
 308   for (size_t i = 0; i < maps.size(); i++) {
 309     simgrid::xbt::VmMap const& reg = maps[i];
 310     const char* pathname           = maps[i].pathname.c_str();
 311
 312     // Nothing to do
 313     if (maps[i].pathname.empty()) {
 314       current_name = nullptr;
 315       continue;
 316     }
 317
 318     // [stack], [vvar], [vsyscall], [vdso] ...
 319     if (pathname[0] == '[') {
 320       if ((reg.prot & PROT_WRITE) && not memcmp(pathname, "[stack]", 7)) {
 321         this->maestro_stack_start_ = remote(reg.start_addr);
 322         this->maestro_stack_end_   = remote(reg.end_addr);
 323       }
 324       current_name = nullptr;
 325       continue;
 326     }
 327
 328     if (current_name && strcmp(current_name, pathname) == 0)
 329       continue;
 330
 331     current_name = pathname;
 332     if (not(reg.prot & PROT_READ) && (reg.prot & PROT_EXEC))
 333       continue;
 334
 335     const bool is_executable = not i;
 336     std::string libname;
 337     if (not is_executable) {
 338       libname = get_lib_name(pathname);
 339       if (is_filtered_lib(libname)) {
 340         continue;
 341       }
 342     }
 343
 344     std::shared_ptr<simgrid::mc::ObjectInformation> info =
 345         simgrid::mc::createObjectInformation(this->memory_map_, pathname);
 346     this->object_infos.push_back(info);
 347     if (is_executable)
 348       this->binary_info = info;
 349     else if (is_simgrid_lib(libname))
 350       this->libsimgrid_info = info;
 351   }
 352
 353   // Resolve time (including across different objects):
 354   for (auto const& object_info : this->object_infos)
 355     postProcessObjectInformation(this, object_info.get());
 356
 357   xbt_assert(this->maestro_stack_start_, "Did not find maestro_stack_start");
 358   xbt_assert(this->maestro_stack_end_, "Did not find maestro_stack_end");
 359
 360   XBT_DEBUG("Get debug information done !");
 361 }
 362
 363 std::shared_ptr<simgrid::mc::ObjectInformation> RemoteClient::find_object_info(RemotePtr<void> addr) const
 364 {
 365   for (auto const& object_info : this->object_infos)
 366     if (addr.address() >= (std::uint64_t)object_info->start && addr.address() <= (std::uint64_t)object_info->end)
 367       return object_info;
 368   return nullptr;
 369 }
 370
 371 std::shared_ptr<ObjectInformation> RemoteClient::find_object_info_exec(RemotePtr<void> addr) const
 372 {
 373   for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
 374     if (addr.address() >= (std::uint64_t)info->start_exec && addr.address() <= (std::uint64_t)info->end_exec)
 375       return info;
 376   return nullptr;
 377 }
 378
 379 std::shared_ptr<ObjectInformation> RemoteClient::find_object_info_rw(RemotePtr<void> addr) const
 380 {
 381   for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
 382     if (addr.address() >= (std::uint64_t)info->start_rw && addr.address() <= (std::uint64_t)info->end_rw)
 383       return info;
 384   return nullptr;
 385 }
 386
 387 simgrid::mc::Frame* RemoteClient::find_function(RemotePtr<void> ip) const
 388 {
 389   std::shared_ptr<simgrid::mc::ObjectInformation> info = this->find_object_info_exec(ip);
 390   return info ? info->find_function((void*)ip.address()) : nullptr;
 391 }
 392
 393 /** Find (one occurrence of) the named variable definition
 394  */
 395 simgrid::mc::Variable* RemoteClient::find_variable(const char* name) const
 396 {
 397   // First lookup the variable in the executable shared object.
 398   // A global variable used directly by the executable code from a library
 399   // is reinstanciated in the executable memory .data/.bss.
 400   // We need to look up the variable in the executable first.
 401   if (this->binary_info) {
 402     std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->binary_info;
 403     simgrid::mc::Variable* var                                  = info->find_variable(name);
 404     if (var)
 405       return var;
 406   }
 407
 408   for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos) {
 409     simgrid::mc::Variable* var = info->find_variable(name);
 410     if (var)
 411       return var;
 412   }
 413
 414   return nullptr;
 415 }
 416
 417 void RemoteClient::read_variable(const char* name, void* target, size_t size) const
 418 {
 419   simgrid::mc::Variable* var = this->find_variable(name);
 420   xbt_assert(var->address, "No simple location for this variable");
 421   xbt_assert(var->type->full_type, "Partial type for %s, cannot check size", name);
 422   xbt_assert((size_t)var->type->full_type->byte_size == size, "Unexpected size for %s (expected %zu, was %zu)", name,
 423              size, (size_t)var->type->full_type->byte_size);
 424   this->read_bytes(target, size, remote(var->address));
 425 }
 426
 427 std::string RemoteClient::read_string(RemotePtr<char> address) const
 428 {
 429   if (not address)
 430     return {};
 431
 432   std::vector<char> res(128);
 433   off_t off = 0;
 434
 435   while (1) {
 436     ssize_t c = pread(this->memory_file, res.data() + off, res.size() - off, (off_t)address.address() + off);
 437     if (c == -1) {
 438       if (errno == EINTR)
 439         continue;
 440       else
 441         xbt_die("Could not read from from remote process");
 442     }
 443     if (c == 0)
 444       xbt_die("Could not read string from remote process");
 445
 446     void* p = memchr(res.data() + off, '\0', c);
 447     if (p)
 448       return std::string(res.data());
 449
 450     off += c;
 451     if (off == (off_t)res.size())
 452       res.resize(res.size() * 2);
 453   }
 454 }
 455
 456 const void* RemoteClient::read_bytes(void* buffer, std::size_t size, RemotePtr<void> address, int process_index,
 457                                      ReadOptions options) const
 458 {
 459 #if HAVE_SMPI
 460   if (process_index != simgrid::mc::ProcessIndexDisabled) {
 461     std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->find_object_info_rw(address);
 462     // Segment overlap is not handled.
 463     if (info.get() && this->privatized(*info)) {
 464       if (process_index < 0)
 465         xbt_die("Missing process index");
 466       if (process_index >= (int)MC_smpi_process_count())
 467         xbt_die("Invalid process index");
 468
 469       // Read smpi_privatization_regions from MCed:
 470       smpi_privatization_region_t remote_smpi_privatization_regions =
 471           mc_model_checker->process().read_variable<smpi_privatization_region_t>("smpi_privatization_regions");
 472
 473       s_smpi_privatization_region_t privatization_region =
 474           mc_model_checker->process().read<s_smpi_privatization_region_t>(
 475               remote(remote_smpi_privatization_regions + process_index));
 476
 477       // Address translation in the privatization segment:
 478       size_t offset = address.address() - (std::uint64_t)info->start_rw;
 479       address       = remote((char*)privatization_region.address + offset);
 480     }
 481   }
 482 #endif
 483   if (pread_whole(this->memory_file, buffer, size, (size_t)address.address()) < 0)
 484     xbt_die("Read at %p from process %lli failed", (void*)address.address(), (long long)this->pid_);
 485   return buffer;
 486 }
 487
 488 /** Write data to a process memory
 489  *
 490  *  @param buffer   local memory address (source)
 491  *  @param len      data size
 492  *  @param address  target process memory address (target)
 493  */
 494 void RemoteClient::write_bytes(const void* buffer, size_t len, RemotePtr<void> address)
 495 {
 496   if (pwrite_whole(this->memory_file, buffer, len, (size_t)address.address()) < 0)
 497     xbt_die("Write to process %lli failed", (long long)this->pid_);
 498 }
 499
 500 void RemoteClient::clear_bytes(RemotePtr<void> address, size_t len)
 501 {
 502   pthread_once(&zero_buffer_flag, zero_buffer_init);
 503   while (len) {
 504     size_t s = len > zero_buffer_size ? zero_buffer_size : len;
 505     this->write_bytes(zero_buffer, s, address);
 506     address = remote((char*)address.address() + s);
 507     len -= s;
 508   }
 509 }
 510
 511 void RemoteClient::ignore_region(std::uint64_t addr, std::size_t size)
 512 {
 513   IgnoredRegion region;
 514   region.addr = addr;
 515   region.size = size;
 516
 517   if (ignored_regions_.empty()) {
 518     ignored_regions_.push_back(region);
 519     return;
 520   }
 521
 522   unsigned int cursor           = 0;
 523   IgnoredRegion* current_region = nullptr;
 524
 525   int start = 0;
 526   int end   = ignored_regions_.size() - 1;
 527   while (start <= end) {
 528     cursor         = (start + end) / 2;
 529     current_region = &ignored_regions_[cursor];
 530     if (current_region->addr == addr) {
 531       if (current_region->size == size)
 532         return;
 533       else if (current_region->size < size)
 534         start = cursor + 1;
 535       else
 536         end = cursor - 1;
 537     } else if (current_region->addr < addr)
 538       start = cursor + 1;
 539     else
 540       end = cursor - 1;
 541   }
 542
 543   std::size_t position;
 544   if (current_region->addr == addr) {
 545     if (current_region->size < size)
 546       position = cursor + 1;
 547     else
 548       position = cursor;
 549   } else if (current_region->addr < addr)
 550     position = cursor + 1;
 551   else
 552     position = cursor;
 553   ignored_regions_.insert(ignored_regions_.begin() + position, region);
 554 }
 555
 556 void RemoteClient::ignore_heap(IgnoredHeapRegion const& region)
 557 {
 558   if (ignored_heap_.empty()) {
 559     ignored_heap_.push_back(std::move(region));
 560     return;
 561   }
 562
 563   typedef std::vector<IgnoredHeapRegion>::size_type size_type;
 564
 565   size_type start = 0;
 566   size_type end   = ignored_heap_.size() - 1;
 567
 568   // Binary search the position of insertion:
 569   size_type cursor;
 570   while (start <= end) {
 571     cursor               = start + (end - start) / 2;
 572     auto& current_region = ignored_heap_[cursor];
 573     if (current_region.address == region.address)
 574       return;
 575     else if (current_region.address < region.address)
 576       start = cursor + 1;
 577     else if (cursor != 0)
 578       end = cursor - 1;
 579     // Avoid underflow:
 580     else
 581       break;
 582   }
 583
 584   // Insert it mc_heap_ignore_region_t:
 585   if (ignored_heap_[cursor].address < region.address)
 586     ++cursor;
 587   ignored_heap_.insert(ignored_heap_.begin() + cursor, region);
 588 }
 589
 590 void RemoteClient::unignore_heap(void* address, size_t size)
 591 {
 592   typedef std::vector<IgnoredHeapRegion>::size_type size_type;
 593
 594   size_type start = 0;
 595   size_type end   = ignored_heap_.size() - 1;
 596
 597   // Binary search:
 598   size_type cursor;
 599   while (start <= end) {
 600     cursor       = (start + end) / 2;
 601     auto& region = ignored_heap_[cursor];
 602     if (region.address < address)
 603       start = cursor + 1;
 604     else if ((char*)region.address <= ((char*)address + size)) {
 605       ignored_heap_.erase(ignored_heap_.begin() + cursor);
 606       return;
 607     } else if (cursor != 0)
 608       end = cursor - 1;
 609     // Avoid underflow:
 610     else
 611       break;
 612   }
 613 }
 614
 615 void RemoteClient::ignore_local_variable(const char* var_name, const char* frame_name)
 616 {
 617   if (frame_name != nullptr && strcmp(frame_name, "*") == 0)
 618     frame_name = nullptr;
 619   for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos)
 620     info->remove_local_variable(var_name, frame_name);
 621 }
 622
 623 std::vector<simgrid::mc::ActorInformation>& RemoteClient::actors()
 624 {
 625   this->refresh_simix();
 626   return smx_actors_infos;
 627 }
 628
 629 std::vector<simgrid::mc::ActorInformation>& RemoteClient::dead_actors()
 630 {
 631   this->refresh_simix();
 632   return smx_dead_actors_infos;
 633 }
 634
 635 void RemoteClient::dumpStack()
 636 {
 637   unw_addr_space_t as = unw_create_addr_space(&_UPT_accessors, BYTE_ORDER);
 638   if (as == nullptr) {
 639     XBT_ERROR("Could not initialize ptrace address space");
 640     return;
 641   }
 642
 643   void* context = _UPT_create(this->pid_);
 644   if (context == nullptr) {
 645     unw_destroy_addr_space(as);
 646     XBT_ERROR("Could not initialize ptrace context");
 647     return;
 648   }
 649
 650   unw_cursor_t cursor;
 651   if (unw_init_remote(&cursor, as, context) != 0) {
 652     _UPT_destroy(context);
 653     unw_destroy_addr_space(as);
 654     XBT_ERROR("Could not initialiez ptrace cursor");
 655     return;
 656   }
 657
 658   simgrid::mc::dumpStack(stderr, cursor);
 659
 660   _UPT_destroy(context);
 661   unw_destroy_addr_space(as);
 662 }
 663
 664 bool RemoteClient::actor_is_enabled(aid_t pid)
 665 {
 666   s_mc_message_actor_enabled_t msg{MC_MESSAGE_ACTOR_ENABLED, pid};
 667   process()->getChannel().send(msg);
 668   char buff[MC_MESSAGE_LENGTH];
 669   ssize_t received = process()->getChannel().receive(buff, MC_MESSAGE_LENGTH, true);
 670   xbt_assert(received == sizeof(s_mc_message_int_t), "Unexpected size in answer to ACTOR_ENABLED");
 671   return ((s_mc_message_int_t*)buff)->value;
 672 }
 673 }
 674 }