Ziele Untersuchung
mit Columbo Integrität von
Datenbanken Interaktion und
Portierbarkeit Ergonomie der
Schnittstellen

Angebot Produkte Projekt Beratung

Mittel Analytik Modellierung Sprachen Algebra Logik Hardware Denken Kreativität

Zusammenhänge Gesellschaft Wirtschaft Branche Firma


products/sources/formale Sprachen/Java/Openjdk/src/hotspot/share/classfile/ (Sun/Oracle ^©) Datei vom 13.11.2022 mit Größe 16 kB

Quelle packageEntry.cpp Sprache: C

/*
* Copyright (c) 2016, 2022, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/

#include "precompiled.hpp"
#include "cds/archiveBuilder.hpp"
#include "cds/archiveUtils.hpp"
#include "classfile/classLoaderData.hpp"
#include "classfile/moduleEntry.hpp"
#include "classfile/packageEntry.hpp"
#include "classfile/vmSymbols.hpp"
#include "logging/log.hpp"
#include "memory/resourceArea.hpp"
#include "oops/array.hpp"
#include "oops/symbol.hpp"
#include "runtime/java.hpp"
#include "runtime/handles.inline.hpp"
#include "utilities/events.hpp"
#include "utilities/growableArray.hpp"
#include "utilities/ostream.hpp"
#include "utilities/quickSort.hpp"
#include "utilities/resourceHash.hpp"

PackageEntry::PackageEntry(Symbol* name, ModuleEntry* module) :
  _name(name),
  _module(module),
  _export_flags(0),
  _classpath_index(-1),
  _must_walk_exports(false),
  _qualified_exports(NULL),
  _defined_by_cds_in_class_path(0)
{
  // name can't be null
  _name->increment_refcount();

  JFR_ONLY(INIT_ID(this);)
}

PackageEntry::~PackageEntry() {
  delete_qualified_exports();
  _name->decrement_refcount();
}

// Returns true if this package specifies m as a qualified export, including through an unnamed export
bool PackageEntry::is_qexported_to(ModuleEntry* m) const {
  assert(Module_lock->owned_by_self(), "should have the Module_lock");
  assert(m != NULL, "No module to lookup in this package's qualified exports list");
  if (is_exported_allUnnamed() && !m->is_named()) {
    return true;
  } else if (!has_qual_exports_list()) {
    return false;
  } else {
    return _qualified_exports->contains(m);
  }
}

// Add a module to the package's qualified export list.
void PackageEntry::add_qexport(ModuleEntry* m) {
  assert(Module_lock->owned_by_self(), "should have the Module_lock");
  if (!has_qual_exports_list()) {
    // Lazily create a package's qualified exports list.
    // Initial size is small, do not anticipate export lists to be large.
    _qualified_exports = new (mtModule) GrowableArray<ModuleEntry*>(QUAL_EXP_SIZE, mtModule);
  }

  // Determine, based on this newly established export to module m,
  // if this package's export list should be walked at a GC safepoint.
  set_export_walk_required(m->loader_data());

  // Establish exportability to module m
  _qualified_exports->append_if_missing(m);
}

// If the module's loader, that an export is being established to, is
// not the same loader as this module's and is not one of the 3 builtin
// class loaders, then this package's export list must be walked at GC
// safepoint. Modules have the same life cycle as their defining class
// loaders and should be removed if dead.
void PackageEntry::set_export_walk_required(ClassLoaderData* m_loader_data) {
  assert_locked_or_safepoint(Module_lock);
  ModuleEntry* this_pkg_mod = module();
  if (!_must_walk_exports &&
      (this_pkg_mod == NULL || this_pkg_mod->loader_data() != m_loader_data) &&
      !m_loader_data->is_builtin_class_loader_data()) {
    _must_walk_exports = true;
    if (log_is_enabled(Trace, module)) {
      ResourceMark rm;
      assert(name() != NULL, "PackageEntry without a valid name");
      log_trace(module)("PackageEntry::set_export_walk_required(): package %s defined in module %s, exports list must be walked",
                        name()->as_C_string(),
                        (this_pkg_mod == NULL || this_pkg_mod->name() == NULL) ?
                          UNNAMED_MODULE : this_pkg_mod->name()->as_C_string());
    }
  }
}

// Set the package's exported states based on the value of the ModuleEntry.
void PackageEntry::set_exported(ModuleEntry* m) {
  assert(Module_lock->owned_by_self(), "should have the Module_lock");
  if (is_unqual_exported()) {
    // An exception could be thrown, but choose to simply ignore.
    // Illegal to convert an unqualified exported package to be qualifiedly exported
    return;
  }

  if (m == NULL) {
    // NULL indicates the package is being unqualifiedly exported.  Clean up
    // the qualified list at the next safepoint.
    set_unqual_exported();
  } else {
    // Add the exported module
    add_qexport(m);
  }
}

// Set the package as exported to all unnamed modules unless the package is
// already unqualifiedly exported.
void PackageEntry::set_is_exported_allUnnamed() {
  assert(!module()->is_open(), "should have been checked already");
  assert(Module_lock->owned_by_self(), "should have the Module_lock");
  if (!is_unqual_exported()) {
   _export_flags = PKG_EXP_ALLUNNAMED;
  }
}

// Remove dead module entries within the package's exported list.  Note that
// if all of the modules on the _qualified_exports get purged the list does not
// get deleted.  This prevents the package from illegally transitioning from
// exported to non-exported.
void PackageEntry::purge_qualified_exports() {
  assert_locked_or_safepoint(Module_lock);
  if (_must_walk_exports &&
      _qualified_exports != NULL &&
      !_qualified_exports->is_empty()) {

    // This package's _must_walk_exports flag will be reset based
    // on the remaining live modules on the exports list.
    _must_walk_exports = false;

    if (log_is_enabled(Trace, module)) {
      ResourceMark rm;
      assert(name() != NULL, "PackageEntry without a valid name");
      ModuleEntry* pkg_mod = module();
      log_trace(module)("PackageEntry::purge_qualified_exports(): package %s defined in module %s, exports list being walked",
                        name()->as_C_string(),
                        (pkg_mod == NULL || pkg_mod->name() == NULL) ? UNNAMED_MODULE : pkg_mod->name()->as_C_string());
    }

    // Go backwards because this removes entries that are dead.
    int len = _qualified_exports->length();
    for (int idx = len - 1; idx >= 0; idx--) {
      ModuleEntry* module_idx = _qualified_exports->at(idx);
      ClassLoaderData* cld_idx = module_idx->loader_data();
      if (cld_idx->is_unloading()) {
        _qualified_exports->delete_at(idx);
      } else {
        // Update the need to walk this package's exports based on live modules
        set_export_walk_required(cld_idx);
      }
    }
  }
}

void PackageEntry::delete_qualified_exports() {
  if (_qualified_exports != NULL) {
    delete _qualified_exports;
  }
  _qualified_exports = NULL;
}

PackageEntryTable::PackageEntryTable() { }

PackageEntryTable::~PackageEntryTable() {
  class PackageEntryTableDeleter : public StackObj {
   public:
    bool do_entry(const SymbolHandle& name, PackageEntry*& entry) {
      if (log_is_enabled(Info, module, unload) || log_is_enabled(Debug, module)) {
        ResourceMark rm;
        const char* str = name->as_C_string();
        log_info(module, unload)("unloading package %s", str);
        log_debug(module)("PackageEntry: deleting package: %s", str);
      }
      delete entry;
      return true;
    }
  };

  PackageEntryTableDeleter deleter;
  _table.unlink(&deleter);
  assert(_table.number_of_entries() == 0, "should have removed all entries");
}

#if INCLUDE_CDS_JAVA_HEAP
typedef ResourceHashtable<
  const PackageEntry*,
  PackageEntry*,
  557, // prime number
  AnyObj::C_HEAP> ArchivedPackageEntries;
static ArchivedPackageEntries* _archived_packages_entries = NULL;

PackageEntry* PackageEntry::allocate_archived_entry() const {
  assert(!in_unnamed_module(), "unnamed packages/modules are not archived");
  PackageEntry* archived_entry = (PackageEntry*)ArchiveBuilder::rw_region_alloc(sizeof(PackageEntry));
  memcpy((void*)archived_entry, (void*)this, sizeof(PackageEntry));

  if (_archived_packages_entries == NULL) {
    _archived_packages_entries = new (mtClass)ArchivedPackageEntries();
  }
  assert(_archived_packages_entries->get(this) == NULL, "Each PackageEntry must not be shared across PackageEntryTables");
  _archived_packages_entries->put(this, archived_entry);

  return archived_entry;
}

PackageEntry* PackageEntry::get_archived_entry(PackageEntry* orig_entry) {
  PackageEntry** ptr = _archived_packages_entries->get(orig_entry);
  if (ptr != NULL) {
    return *ptr;
  } else {
    return NULL;
  }
}

void PackageEntry::iterate_symbols(MetaspaceClosure* closure) {
  closure->push(&_name);
}

void PackageEntry::init_as_archived_entry() {
  Array<ModuleEntry*>* archived_qualified_exports = ModuleEntry::write_growable_array(_qualified_exports);

  _name = ArchiveBuilder::get_buffered_symbol(_name);
  _module = ModuleEntry::get_archived_entry(_module);
  _qualified_exports = (GrowableArray<ModuleEntry*>*)archived_qualified_exports;
  _defined_by_cds_in_class_path = 0;
  JFR_ONLY(set_trace_id(0)); // re-init at runtime

  ArchivePtrMarker::mark_pointer((address*)&_name);
  ArchivePtrMarker::mark_pointer((address*)&_module);
  ArchivePtrMarker::mark_pointer((address*)&_qualified_exports);
}

void PackageEntry::load_from_archive() {
  _qualified_exports = ModuleEntry::restore_growable_array((Array<ModuleEntry*>*)_qualified_exports);
  JFR_ONLY(INIT_ID(this);)
}

static int compare_package_by_name(PackageEntry* a, PackageEntry* b) {
  assert(a == b || a->name() != b->name(), "no duplicated names");
  return a->name()->fast_compare(b->name());
}

void PackageEntryTable::iterate_symbols(MetaspaceClosure* closure) {
  auto syms = [&] (const SymbolHandle& key, PackageEntry*& p) {
      p->iterate_symbols(closure);
  };
  _table.iterate_all(syms);
}

Array<PackageEntry*>* PackageEntryTable::allocate_archived_entries() {
  // First count the packages in named modules
  int n = 0;
  auto count = [&] (const SymbolHandle& key, PackageEntry*& p) {
    if (p->module()->is_named()) {
      n++;
    }
  };
  _table.iterate_all(count);

  Array<PackageEntry*>* archived_packages = ArchiveBuilder::new_rw_array<PackageEntry*>(n);
  // reset n
  n = 0;
  auto grab = [&] (const SymbolHandle& key, PackageEntry*& p) {
    if (p->module()->is_named()) {
      // We don't archive unnamed modules, or packages in unnamed modules. They will be
      // created on-demand at runtime as classes in such packages are loaded.
      archived_packages->at_put(n++, p);
    }
  };
  _table.iterate_all(grab);

  if (n > 1) {
    QuickSort::sort(archived_packages->data(), n, (_sort_Fn)compare_package_by_name, true);
  }
  for (int i = 0; i < n; i++) {
    archived_packages->at_put(i, archived_packages->at(i)->allocate_archived_entry());
    ArchivePtrMarker::mark_pointer((address*)archived_packages->adr_at(i));
  }
  return archived_packages;
}

void PackageEntryTable::init_archived_entries(Array<PackageEntry*>* archived_packages) {
  for (int i = 0; i < archived_packages->length(); i++) {
    PackageEntry* archived_entry = archived_packages->at(i);
    archived_entry->init_as_archived_entry();
  }
}

void PackageEntryTable::load_archived_entries(Array<PackageEntry*>* archived_packages) {
  assert(UseSharedSpaces, "runtime only");

  for (int i = 0; i < archived_packages->length(); i++) {
    PackageEntry* archived_entry = archived_packages->at(i);
    archived_entry->load_from_archive();
    _table.put(archived_entry->name(), archived_entry);
  }
}

#endif // INCLUDE_CDS_JAVA_HEAP

// Create package entry in loader's package entry table.  Assume Module lock
// was taken by caller.
void PackageEntryTable::locked_create_entry(Symbol* name, ModuleEntry* module) {
  assert(Module_lock->owned_by_self(), "should have the Module_lock");
  assert(locked_lookup_only(name) == NULL, "Package entry already exists");
  PackageEntry* entry = new PackageEntry(name, module);
  bool created = _table.put(name, entry);
  assert(created, "must be");
}

// Create package entry in loader's package entry table if it does not already
// exist.  Assume Module lock was taken by caller.
PackageEntry* PackageEntryTable::locked_create_entry_if_absent(Symbol* name, ModuleEntry* module) {
  assert(Module_lock->owned_by_self(), "should have the Module_lock");
  // Check if package entry already exists.  If not, create it.
  bool created;
  PackageEntry* entry = new PackageEntry(name, module);
  PackageEntry** old_entry = _table.put_if_absent(name, entry, &created);
  if (created) {
    return entry;
  } else {
    delete entry;
    return *old_entry;
  }
}

PackageEntry* PackageEntryTable::create_entry_if_absent(Symbol* name, ModuleEntry* module) {
  MutexLocker ml(Module_lock);
  return locked_create_entry_if_absent(name, module);
}

PackageEntry* PackageEntryTable::lookup_only(Symbol* name) {
  assert(!Module_lock->owned_by_self(), "should not have the Module_lock - use locked_lookup_only");
  MutexLocker ml(Module_lock);
  return locked_lookup_only(name);
}

PackageEntry* PackageEntryTable::locked_lookup_only(Symbol* name) {
  assert(Module_lock->owned_by_self(), "should have the Module_lock");
  PackageEntry** entry = _table.get(name);
  return entry == nullptr ? nullptr : *entry;
}

// Called when a define module for java.base is being processed.
// Verify the packages loaded thus far are in java.base's package list.
void PackageEntryTable::verify_javabase_packages(GrowableArray<Symbol*> *pkg_list) {
  assert_lock_strong(Module_lock);
  auto verifier = [&] (const SymbolHandle& name, PackageEntry*& entry) {
    ModuleEntry* m = entry->module();
    Symbol* module_name = (m == NULL ? NULL : m->name());
    if (module_name != NULL &&
      (module_name->fast_compare(vmSymbols::java_base()) == 0) &&
        !pkg_list->contains(entry->name())) {
      ResourceMark rm;
      vm_exit_during_initialization("A non-" JAVA_BASE_NAME " package was loaded prior to module system initialization",
                                    entry->name()->as_C_string());
    }
  };
  _table.iterate_all(verifier);
}

// iteration of qualified exports
void PackageEntry::package_exports_do(ModuleClosure* f) {
  assert_locked_or_safepoint(Module_lock);
  assert(f != NULL, "invariant");

  if (has_qual_exports_list()) {
    int qe_len = _qualified_exports->length();

    for (int i = 0; i < qe_len; ++i) {
      f->do_module(_qualified_exports->at(i));
    }
  }
}

bool PackageEntry::exported_pending_delete() const {
  assert_locked_or_safepoint(Module_lock);
  return (is_unqual_exported() && _qualified_exports != NULL);
}

// Remove dead entries from all packages' exported list
void PackageEntryTable::purge_all_package_exports() {
  assert_locked_or_safepoint(Module_lock);
  auto purge = [&] (const SymbolHandle& name, PackageEntry*& entry) {
    if (entry->exported_pending_delete()) {
      // exported list is pending deletion due to a transition
      // from qualified to unqualified
      entry->delete_qualified_exports();
    } else if (entry->is_qual_exported()) {
      entry->purge_qualified_exports();
    }
  };
  _table.iterate_all(purge);
}

void PackageEntryTable::packages_do(void f(PackageEntry*)) {
  auto doit = [&] (const SymbolHandle&name, PackageEntry*& entry) {
    f(entry);
  };
  assert_locked_or_safepoint(Module_lock);
  _table.iterate_all(doit);
}

GrowableArray<PackageEntry*>*  PackageEntryTable::get_system_packages() {
  GrowableArray<PackageEntry*>* loaded_class_pkgs = new GrowableArray<PackageEntry*>(50);
  auto grab = [&] (const SymbolHandle& name, PackageEntry*& entry) {
    if (entry->has_loaded_class()) {
      loaded_class_pkgs->append(entry);
    }
  };

  MutexLocker ml(Module_lock);
  _table.iterate_all(grab);
  // Returns a resource allocated object so caller must have ResourceMark
  return loaded_class_pkgs;
}

void PackageEntryTable::print(outputStream* st) {
  auto printer = [&] (const SymbolHandle& name, PackageEntry*& entry) {
    entry->print(st);
  };
  st->print_cr("Package Entry Table (table_size=%d, entries=%d)",
               _table.table_size(), _table.number_of_entries());
  _table.iterate_all(printer);
}

// This function may be called from debuggers so access private fields directly
// to prevent triggering locking-related asserts that could result from calling
// getter methods.
void PackageEntry::print(outputStream* st) {
  ResourceMark rm;
  st->print_cr("package entry " PTR_FORMAT " name %s module %s classpath_index "
               INT32_FORMAT " is_exported_unqualified %d is_exported_allUnnamed %d ",
               p2i(this), name()->as_C_string(),
               (module()->is_named() ? module()->name()->as_C_string() : UNNAMED_MODULE),
               _classpath_index, _export_flags == PKG_EXP_UNQUALIFIED,
               _export_flags == PKG_EXP_ALLUNNAMED);
}

quality93%

¤ Dauer der Verarbeitung: 0.17 Sekunden (vorverarbeitet) ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.