1 /*
  2  * Copyright (c) 2023, 2024, 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 #include "precompiled.hpp"
 26 #include "cds/archiveHeapLoader.hpp"
 27 #include "cds/cdsConfig.hpp"
 28 #include "cds/classListWriter.hpp"
 29 #include "cds/heapShared.hpp"
 30 #include "classfile/classLoaderDataShared.hpp"
 31 #include "classfile/moduleEntry.hpp"
 32 #include "include/jvm_io.h"
 33 #include "logging/log.hpp"
 34 #include "memory/universe.hpp"
 35 #include "runtime/arguments.hpp"
 36 #include "runtime/java.hpp"
 37 #include "utilities/defaultStream.hpp"
 38 
 39 bool CDSConfig::_is_dumping_static_archive = false;
 40 bool CDSConfig::_is_dumping_dynamic_archive = false;
 41 bool CDSConfig::_is_using_optimized_module_handling = true;
 42 bool CDSConfig::_is_dumping_full_module_graph = true;
 43 bool CDSConfig::_is_using_full_module_graph = true;
 44 
 45 char* CDSConfig::_default_archive_path = nullptr;
 46 char* CDSConfig::_static_archive_path = nullptr;
 47 char* CDSConfig::_dynamic_archive_path = nullptr;
 48 
 49 int CDSConfig::get_status() {
 50   assert(Universe::is_fully_initialized(), "status is finalized only after Universe is initialized");
 51   return (is_dumping_archive()              ? IS_DUMPING_ARCHIVE : 0) |
 52          (is_dumping_static_archive()       ? IS_DUMPING_STATIC_ARCHIVE : 0) |
 53          (is_logging_lambda_form_invokers() ? IS_LOGGING_LAMBDA_FORM_INVOKERS : 0) |
 54          (is_using_archive()                ? IS_USING_ARCHIVE : 0);
 55 }
 56 
 57 
 58 void CDSConfig::initialize() {
 59   if (is_dumping_static_archive()) {
 60     if (RequireSharedSpaces) {
 61       warning("Cannot dump shared archive while using shared archive");
 62     }
 63     UseSharedSpaces = false;
 64   }
 65 
 66   // Initialize shared archive paths which could include both base and dynamic archive paths
 67   // This must be after set_ergonomics_flags() called so flag UseCompressedOops is set properly.
 68   //
 69   // UseSharedSpaces may be disabled if -XX:SharedArchiveFile is invalid.
 70   if (is_dumping_static_archive() || is_using_archive()) {
 71     init_shared_archive_paths();
 72   }
 73 
 74   if (!is_dumping_heap()) {
 75     _is_dumping_full_module_graph = false;
 76   }
 77 }
 78 
 79 char* CDSConfig::default_archive_path() {
 80   if (_default_archive_path == nullptr) {
 81     char jvm_path[JVM_MAXPATHLEN];
 82     os::jvm_path(jvm_path, sizeof(jvm_path));
 83     char *end = strrchr(jvm_path, *os::file_separator());
 84     if (end != nullptr) *end = '\0';
 85     size_t jvm_path_len = strlen(jvm_path);
 86     size_t file_sep_len = strlen(os::file_separator());
 87     const size_t len = jvm_path_len + file_sep_len + 20;
 88     _default_archive_path = NEW_C_HEAP_ARRAY(char, len, mtArguments);
 89     jio_snprintf(_default_archive_path, len,
 90                 LP64_ONLY(!UseCompressedOops ? "%s%sclasses_nocoops.jsa":) "%s%sclasses.jsa",
 91                 jvm_path, os::file_separator());
 92   }
 93   return _default_archive_path;
 94 }
 95 
 96 int CDSConfig::num_archives(const char* archive_path) {
 97   if (archive_path == nullptr) {
 98     return 0;
 99   }
100   int npaths = 1;
101   char* p = (char*)archive_path;
102   while (*p != '\0') {
103     if (*p == os::path_separator()[0]) {
104       npaths++;
105     }
106     p++;
107   }
108   return npaths;
109 }
110 
111 void CDSConfig::extract_shared_archive_paths(const char* archive_path,
112                                              char** base_archive_path,
113                                              char** top_archive_path) {
114   char* begin_ptr = (char*)archive_path;
115   char* end_ptr = strchr((char*)archive_path, os::path_separator()[0]);
116   if (end_ptr == nullptr || end_ptr == begin_ptr) {
117     vm_exit_during_initialization("Base archive was not specified", archive_path);
118   }
119   size_t len = end_ptr - begin_ptr;
120   char* cur_path = NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
121   strncpy(cur_path, begin_ptr, len);
122   cur_path[len] = '\0';
123   *base_archive_path = cur_path;
124 
125   begin_ptr = ++end_ptr;
126   if (*begin_ptr == '\0') {
127     vm_exit_during_initialization("Top archive was not specified", archive_path);
128   }
129   end_ptr = strchr(begin_ptr, '\0');
130   assert(end_ptr != nullptr, "sanity");
131   len = end_ptr - begin_ptr;
132   cur_path = NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
133   strncpy(cur_path, begin_ptr, len + 1);
134   *top_archive_path = cur_path;
135 }
136 
137 void CDSConfig::init_shared_archive_paths() {
138   if (ArchiveClassesAtExit != nullptr) {
139     assert(!RecordDynamicDumpInfo, "already checked");
140     if (is_dumping_static_archive()) {
141       vm_exit_during_initialization("-XX:ArchiveClassesAtExit cannot be used with -Xshare:dump");
142     }
143     check_unsupported_dumping_module_options();
144 
145     if (os::same_files(default_archive_path(), ArchiveClassesAtExit)) {
146       vm_exit_during_initialization(
147         "Cannot specify the default CDS archive for -XX:ArchiveClassesAtExit", default_archive_path());
148     }
149   }
150 
151   if (SharedArchiveFile == nullptr) {
152     _static_archive_path = default_archive_path();
153   } else {
154     int archives = num_archives(SharedArchiveFile);
155     assert(archives > 0, "must be");
156 
157     if (is_dumping_archive() && archives > 1) {
158       vm_exit_during_initialization(
159         "Cannot have more than 1 archive file specified in -XX:SharedArchiveFile during CDS dumping");
160     }
161 
162     if (is_dumping_static_archive()) {
163       assert(archives == 1, "must be");
164       // Static dump is simple: only one archive is allowed in SharedArchiveFile. This file
165       // will be overwritten no matter regardless of its contents
166       _static_archive_path = os::strdup_check_oom(SharedArchiveFile, mtArguments);
167     } else {
168       // SharedArchiveFile may specify one or two files. In case (c), the path for base.jsa
169       // is read from top.jsa
170       //    (a) 1 file:  -XX:SharedArchiveFile=base.jsa
171       //    (b) 2 files: -XX:SharedArchiveFile=base.jsa:top.jsa
172       //    (c) 2 files: -XX:SharedArchiveFile=top.jsa
173       //
174       // However, if either RecordDynamicDumpInfo or ArchiveClassesAtExit is used, we do not
175       // allow cases (b) and (c). Case (b) is already checked above.
176 
177       if (archives > 2) {
178         vm_exit_during_initialization(
179           "Cannot have more than 2 archive files specified in the -XX:SharedArchiveFile option");
180       }
181       if (archives == 1) {
182         char* base_archive_path = nullptr;
183         bool success =
184           FileMapInfo::get_base_archive_name_from_header(SharedArchiveFile, &base_archive_path);
185         if (!success) {
186           // If +AutoCreateSharedArchive and the specified shared archive does not exist,
187           // regenerate the dynamic archive base on default archive.
188           if (AutoCreateSharedArchive && !os::file_exists(SharedArchiveFile)) {
189             enable_dumping_dynamic_archive();
190             ArchiveClassesAtExit = const_cast<char *>(SharedArchiveFile);
191             _static_archive_path = default_archive_path();
192             SharedArchiveFile = nullptr;
193           } else {
194             if (AutoCreateSharedArchive) {
195               warning("-XX:+AutoCreateSharedArchive is unsupported when base CDS archive is not loaded. Run with -Xlog:cds for more info.");
196               AutoCreateSharedArchive = false;
197             }
198             Arguments::no_shared_spaces("invalid archive");
199           }
200         } else if (base_archive_path == nullptr) {
201           // User has specified a single archive, which is a static archive.
202           _static_archive_path = const_cast<char *>(SharedArchiveFile);
203         } else {
204           // User has specified a single archive, which is a dynamic archive.
205           _dynamic_archive_path = const_cast<char *>(SharedArchiveFile);
206           _static_archive_path = base_archive_path; // has been c-heap allocated.
207         }
208       } else {
209         extract_shared_archive_paths((const char*)SharedArchiveFile,
210                                       &_static_archive_path, &_dynamic_archive_path);
211         if (_static_archive_path == nullptr) {
212           assert(_dynamic_archive_path == nullptr, "must be");
213           Arguments::no_shared_spaces("invalid archive");
214         }
215       }
216 
217       if (_dynamic_archive_path != nullptr) {
218         // Check for case (c)
219         if (RecordDynamicDumpInfo) {
220           vm_exit_during_initialization("-XX:+RecordDynamicDumpInfo is unsupported when a dynamic CDS archive is specified in -XX:SharedArchiveFile",
221                                         SharedArchiveFile);
222         }
223         if (ArchiveClassesAtExit != nullptr) {
224           vm_exit_during_initialization("-XX:ArchiveClassesAtExit is unsupported when a dynamic CDS archive is specified in -XX:SharedArchiveFile",
225                                         SharedArchiveFile);
226         }
227       }
228 
229       if (ArchiveClassesAtExit != nullptr && os::same_files(SharedArchiveFile, ArchiveClassesAtExit)) {
230           vm_exit_during_initialization(
231             "Cannot have the same archive file specified for -XX:SharedArchiveFile and -XX:ArchiveClassesAtExit",
232             SharedArchiveFile);
233       }
234     }
235   }
236 }
237 
238 void CDSConfig::check_internal_module_property(const char* key, const char* value) {
239   if (Arguments::is_internal_module_property(key)) {
240     stop_using_optimized_module_handling();
241     log_info(cds)("optimized module handling: disabled due to incompatible property: %s=%s", key, value);
242   }
243 }
244 
245 void CDSConfig::check_incompatible_property(const char* key, const char* value) {
246   static const char* incompatible_properties[] = {
247     "java.system.class.loader",
248     "jdk.module.showModuleResolution",
249     "jdk.module.validation"
250   };
251 
252   for (const char* property : incompatible_properties) {
253     if (strcmp(key, property) == 0) {
254       stop_dumping_full_module_graph();
255       stop_using_full_module_graph();
256       log_info(cds)("full module graph: disabled due to incompatible property: %s=%s", key, value);
257       break;
258     }
259   }
260 
261 }
262 
263 // Returns any JVM command-line option, such as "--patch-module", that's not supported by CDS.
264 static const char* find_any_unsupported_module_option() {
265   // Note that arguments.cpp has translated the command-line options into properties. If we find an
266   // unsupported property, translate it back to its command-line option for better error reporting.
267 
268   // The following properties are checked by Arguments::is_internal_module_property() and cannot be
269   // directly specified in the command-line.
270   static const char* unsupported_module_properties[] = {
271     "jdk.module.limitmods",
272     "jdk.module.upgrade.path",
273     "jdk.module.patch.0"
274   };
275   static const char* unsupported_module_options[] = {
276     "--limit-modules",
277     "--upgrade-module-path",
278     "--patch-module"
279   };
280 
281   assert(ARRAY_SIZE(unsupported_module_properties) == ARRAY_SIZE(unsupported_module_options), "must be");
282   SystemProperty* sp = Arguments::system_properties();
283   while (sp != nullptr) {
284     for (uint i = 0; i < ARRAY_SIZE(unsupported_module_properties); i++) {
285       if (strcmp(sp->key(), unsupported_module_properties[i]) == 0) {
286         return unsupported_module_options[i];
287       }
288     }
289     sp = sp->next();
290   }
291 
292   return nullptr; // not found
293 }
294 
295 void CDSConfig::check_unsupported_dumping_module_options() {
296   assert(is_dumping_archive(), "this function is only used with CDS dump time");
297   const char* option = find_any_unsupported_module_option();
298   if (option != nullptr) {
299     vm_exit_during_initialization("Cannot use the following option when dumping the shared archive", option);
300   }
301   // Check for an exploded module build in use with -Xshare:dump.
302   if (!Arguments::has_jimage()) {
303     vm_exit_during_initialization("Dumping the shared archive is not supported with an exploded module build");
304   }
305 }
306 
307 bool CDSConfig::has_unsupported_runtime_module_options() {
308   assert(is_using_archive(), "this function is only used with -Xshare:{on,auto}");
309   if (ArchiveClassesAtExit != nullptr) {
310     // dynamic dumping, just return false for now.
311     // check_unsupported_dumping_properties() will be called later to check the same set of
312     // properties, and will exit the VM with the correct error message if the unsupported properties
313     // are used.
314     return false;
315   }
316   const char* option = find_any_unsupported_module_option();
317   if (option != nullptr) {
318     if (RequireSharedSpaces) {
319       warning("CDS is disabled when the %s option is specified.", option);
320     } else {
321       log_info(cds)("CDS is disabled when the %s option is specified.", option);
322     }
323     return true;
324   }
325   return false;
326 }
327 
328 bool CDSConfig::check_vm_args_consistency(bool patch_mod_javabase, bool mode_flag_cmd_line) {
329   if (is_dumping_static_archive()) {
330     if (!mode_flag_cmd_line) {
331       // By default, -Xshare:dump runs in interpreter-only mode, which is required for deterministic archive.
332       //
333       // If your classlist is large and you don't care about deterministic dumping, you can use
334       // -Xshare:dump -Xmixed to improve dumping speed.
335       Arguments::set_mode_flags(Arguments::_int);
336     } else if (Arguments::mode() == Arguments::_comp) {
337       // -Xcomp may use excessive CPU for the test tiers. Also, -Xshare:dump runs a small and fixed set of
338       // Java code, so there's not much benefit in running -Xcomp.
339       log_info(cds)("reduced -Xcomp to -Xmixed for static dumping");
340       Arguments::set_mode_flags(Arguments::_mixed);
341     }
342 
343     // String deduplication may cause CDS to iterate the strings in different order from one
344     // run to another which resulting in non-determinstic CDS archives.
345     // Disable UseStringDeduplication while dumping CDS archive.
346     UseStringDeduplication = false;
347   }
348 
349   // RecordDynamicDumpInfo is not compatible with ArchiveClassesAtExit
350   if (ArchiveClassesAtExit != nullptr && RecordDynamicDumpInfo) {
351     jio_fprintf(defaultStream::output_stream(),
352                 "-XX:+RecordDynamicDumpInfo cannot be used with -XX:ArchiveClassesAtExit.\n");
353     return false;
354   }
355 
356   if (ArchiveClassesAtExit == nullptr && !RecordDynamicDumpInfo) {
357     disable_dumping_dynamic_archive();
358   } else {
359     enable_dumping_dynamic_archive();
360   }
361 
362   if (AutoCreateSharedArchive) {
363     if (SharedArchiveFile == nullptr) {
364       log_warning(cds)("-XX:+AutoCreateSharedArchive requires -XX:SharedArchiveFile");
365       return false;
366     }
367     if (ArchiveClassesAtExit != nullptr) {
368       log_warning(cds)("-XX:+AutoCreateSharedArchive does not work with ArchiveClassesAtExit");
369       return false;
370     }
371   }
372 
373   if (is_using_archive() && patch_mod_javabase) {
374     Arguments::no_shared_spaces("CDS is disabled when " JAVA_BASE_NAME " module is patched.");
375   }
376   if (is_using_archive() && has_unsupported_runtime_module_options()) {
377     UseSharedSpaces = false;
378   }
379 
380   if (is_dumping_archive()) {
381     // Always verify non-system classes during CDS dump
382     if (!BytecodeVerificationRemote) {
383       BytecodeVerificationRemote = true;
384       log_info(cds)("All non-system classes will be verified (-Xverify:remote) during CDS dump time.");
385     }
386   }
387 
388   return true;
389 }
390 
391 bool CDSConfig::is_using_archive() {
392   return UseSharedSpaces;
393 }
394 
395 bool CDSConfig::is_logging_lambda_form_invokers() {
396   return ClassListWriter::is_enabled() || is_dumping_dynamic_archive();
397 }
398 
399 void CDSConfig::stop_using_optimized_module_handling() {
400   _is_using_optimized_module_handling = false;
401   _is_dumping_full_module_graph = false; // This requires is_using_optimized_module_handling()
402   _is_using_full_module_graph = false; // This requires is_using_optimized_module_handling()
403 }
404 
405 #if INCLUDE_CDS_JAVA_HEAP
406 bool CDSConfig::is_dumping_heap() {
407   // heap dump is not supported in dynamic dump
408   return is_dumping_static_archive() && HeapShared::can_write();
409 }
410 
411 bool CDSConfig::is_using_full_module_graph() {
412   if (ClassLoaderDataShared::is_full_module_graph_loaded()) {
413     return true;
414   }
415 
416   if (!_is_using_full_module_graph) {
417     return false;
418   }
419 
420   if (is_using_archive() && ArchiveHeapLoader::can_use()) {
421     // Classes used by the archived full module graph are loaded in JVMTI early phase.
422     assert(!(JvmtiExport::should_post_class_file_load_hook() && JvmtiExport::has_early_class_hook_env()),
423            "CDS should be disabled if early class hooks are enabled");
424     return true;
425   } else {
426     _is_using_full_module_graph = false;
427     return false;
428   }
429 }
430 
431 void CDSConfig::stop_dumping_full_module_graph(const char* reason) {
432   if (_is_dumping_full_module_graph) {
433     _is_dumping_full_module_graph = false;
434     if (reason != nullptr) {
435       log_info(cds)("full module graph cannot be dumped: %s", reason);
436     }
437   }
438 }
439 
440 void CDSConfig::stop_using_full_module_graph(const char* reason) {
441   assert(!ClassLoaderDataShared::is_full_module_graph_loaded(), "you call this function too late!");
442   if (_is_using_full_module_graph) {
443     _is_using_full_module_graph = false;
444     if (reason != nullptr) {
445       log_info(cds)("full module graph cannot be loaded: %s", reason);
446     }
447   }
448 }
449 #endif // INCLUDE_CDS_JAVA_HEAP