1 /*
   2  * Copyright (c) 2014, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_CLASSFILE_CLASSLOADEREXT_HPP
  26 #define SHARE_VM_CLASSFILE_CLASSLOADEREXT_HPP
  27 
  28 #include "classfile/classLoader.hpp"
  29 #include "classfile/moduleEntry.hpp"
  30 #include "utilities/macros.hpp"
  31 
  32 CDS_ONLY(class SharedPathsMiscInfoExt;)
  33 CDS_ONLY(class ClassListParser;)
  34 
  35 class ClassLoaderExt: public ClassLoader { // AllStatic
  36 public:
  37   enum SomeConstants {
  38     max_classpath_index = 0x7fff
  39   };
  40   // ClassLoaderExt::Context --
  41   //
  42   // This is used by DumpSharedSpaces only - it enforces the same classloader
  43   // delegation model as would be in run-time. I.e.,
  44   // + classes defined by the NULL class loader cannot load classes in the PLATFORM or APP paths.
  45   // + classes defined by the PLATFORM class loader cannot load classes in the APP paths.
  46   class Context {
  47     static Thread* _dump_thread;
  48     const char* _class_name;
  49     const char* _file_name;
  50   public:
  51     const char* class_name() {
  52       return _class_name;
  53     }
  54     const char* file_name() {
  55       return _file_name;
  56     }
  57 
  58     Context(const char* class_name, const char* file_name, TRAPS) {
  59       _class_name = class_name;
  60       _file_name = file_name;
  61 #if INCLUDE_CDS
  62       if (!DumpSharedSpaces && !UseSharedSpaces) {
  63         // Must not modify _app_class_paths_start_index if we're not using CDS.
  64         assert(_app_class_paths_start_index == ClassLoaderExt::max_classpath_index, "must be");
  65       }
  66 #endif
  67     }
  68 
  69     bool should_verify(int classpath_index) {
  70       CDS_ONLY(return (classpath_index >= _app_class_paths_start_index);)
  71       NOT_CDS(return false;)
  72     }
  73 
  74     void record_result(Symbol* class_name,
  75                        const s2 classpath_index,
  76                        InstanceKlass* result,
  77                        TRAPS) {
  78 #if INCLUDE_CDS
  79       ClassLoaderExt::record_result(this, class_name, classpath_index, result, THREAD);
  80 #endif
  81     }
  82 
  83     ~Context() {
  84 #if INCLUDE_CDS
  85       if (!DumpSharedSpaces && !UseSharedSpaces) {
  86         // Must not modify app_class_paths_start_index if we're not using CDS.
  87         assert(_app_class_paths_start_index == ClassLoaderExt::max_classpath_index, "must be");
  88       }
  89 #endif
  90     }
  91   }; // end ClassLoaderExt::Context
  92 
  93 private:
  94 #if INCLUDE_CDS
  95   static char* get_class_path_attr(const char* jar_path, char* manifest, jint manifest_size);
  96   static void setup_app_search_path(); // Only when -Xshare:dump
  97   static void process_module_table(ModuleEntryTable* met, TRAPS);
  98   static void setup_module_search_path(TRAPS);
  99   static SharedPathsMiscInfoExt* shared_paths_misc_info() {
 100     return (SharedPathsMiscInfoExt*)_shared_paths_misc_info;
 101   }
 102   // index of first app JAR in shared classpath entry table
 103   static jshort _app_class_paths_start_index;
 104   // index of first modular JAR in shared modulepath entry table
 105   static jshort _app_module_paths_start_index;
 106 
 107   static bool _has_app_classes;
 108   static bool _has_platform_classes;
 109 #endif
 110 
 111 public:
 112   CDS_ONLY(static void process_jar_manifest(ClassPathEntry* entry, bool check_for_duplicates);)
 113 
 114   // Called by JVMTI code to add boot classpath
 115   static void append_boot_classpath(ClassPathEntry* new_entry) {
 116 #if INCLUDE_CDS
 117     if (UseAppCDS) {
 118       warning("UseAppCDS is disabled because bootstrap classpath has been appended");
 119       UseAppCDS = false;
 120     }
 121 #endif
 122     ClassLoader::add_to_boot_append_entries(new_entry);
 123   }
 124 
 125   static void setup_search_paths() NOT_CDS_RETURN;
 126   static void setup_module_paths(TRAPS) NOT_CDS_RETURN;
 127 
 128 #if INCLUDE_CDS
 129 private:
 130   static char* read_manifest(ClassPathEntry* entry, jint *manifest_size, bool clean_text, TRAPS);
 131   static ClassPathEntry* find_classpath_entry_from_cache(const char* path, TRAPS);
 132 
 133 public:
 134   static char* read_manifest(ClassPathEntry* entry, jint *manifest_size, TRAPS) {
 135     // Remove all the new-line continuations (which wrap long lines at 72 characters, see
 136     // http://docs.oracle.com/javase/6/docs/technotes/guides/jar/jar.html#JAR%20Manifest), so
 137     // that the manifest is easier to parse.
 138     return read_manifest(entry, manifest_size, true, THREAD);
 139   }
 140   static char* read_raw_manifest(ClassPathEntry* entry, jint *manifest_size, TRAPS) {
 141     // Do not remove new-line continuations, so we can easily pass it as an argument to
 142     // java.util.jar.Manifest.getManifest() at run-time.
 143     return read_manifest(entry, manifest_size, false, THREAD);
 144   }
 145 
 146   static void finalize_shared_paths_misc_info();
 147 
 148   static jshort app_class_paths_start_index() { return _app_class_paths_start_index; }
 149 
 150   static jshort app_module_paths_start_index() { return _app_module_paths_start_index; }
 151 
 152   static void init_paths_start_index(jshort app_start) {
 153     _app_class_paths_start_index = app_start;
 154   }
 155 
 156   static void init_app_module_paths_start_index(jshort module_start) {
 157     _app_module_paths_start_index = module_start;
 158   }
 159 
 160   static bool is_boot_classpath(int classpath_index) {
 161     return classpath_index < _app_class_paths_start_index;
 162   }
 163 
 164   static bool has_platform_or_app_classes() {
 165     return _has_app_classes || _has_platform_classes;
 166   }
 167 
 168   static void record_result(class ClassLoaderExt::Context *context,
 169                             Symbol* class_name,
 170                             const s2 classpath_index,
 171                             InstanceKlass* result, TRAPS);
 172   static InstanceKlass* load_class(Symbol* h_name, const char* path, TRAPS);
 173   static Klass* load_one_class(ClassListParser* parser, TRAPS);
 174   static void set_has_app_classes() {
 175     _has_app_classes = true;
 176   }
 177   static void set_has_platform_classes() {
 178     _has_platform_classes = true;
 179   }
 180 #endif
 181 };
 182 
 183 #endif // SHARE_VM_CLASSFILE_CLASSLOADEREXT_HPP