1 /*
2 * Copyright (c) 1997, 2025, 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 "asm/assembler.hpp"
26 #include "classfile/symbolTable.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/vmSymbols.hpp"
29 #include "memory/oopFactory.hpp"
30 #include "memory/resourceArea.hpp"
31 #include "memory/universe.hpp"
32 #include "oops/instanceKlass.hpp"
33 #include "oops/klass.inline.hpp"
34 #include "oops/oop.inline.hpp"
35 #include "oops/symbol.hpp"
36 #include "oops/typeArrayKlass.hpp"
37 #include "runtime/fieldDescriptor.inline.hpp"
38 #include "runtime/handles.inline.hpp"
39 #include "runtime/safepointVerifiers.hpp"
40 #include "runtime/sharedRuntime.hpp"
41 #include "runtime/signature.hpp"
42
43 // Implementation of SignatureIterator
44
45 // Signature syntax:
46 //
47 // Signature = "(" {Parameter} ")" ReturnType.
48 // Parameter = FieldType.
49 // ReturnType = FieldType | "V".
50 // FieldType = "B" | "C" | "D" | "F" | "I" | "J" | "S" | "Z" | "L" ClassName ";" | "[" FieldType.
51 // ClassName = string.
52
53 // The ClassName string can be any JVM-style UTF8 string except:
54 // - an empty string (the empty string is never a name of any kind)
55 // - a string which begins or ends with slash '/' (the package separator)
56 // - a string which contains adjacent slashes '//' (no empty package names)
57 // - a string which contains a semicolon ';' (the end-delimiter)
58 // - a string which contains a left bracket '[' (the array marker)
482 if (name->equals(symbol_chars, len)) {
483 return name;
484 }
485
486 // Save names for cleaning up reference count at the end of
487 // SignatureStream scope.
488 name = SymbolTable::new_symbol(symbol_chars, len);
489
490 // Only allocate the GrowableArray for the _names buffer if more than
491 // one name is being processed in the signature.
492 if (!_previous_name->is_permanent()) {
493 if (_names == nullptr) {
494 _names = new GrowableArray<Symbol*>(10);
495 }
496 _names->push(_previous_name);
497 }
498 _previous_name = name;
499 return name;
500 }
501
502 Klass* SignatureStream::as_klass(Handle class_loader, FailureMode failure_mode, TRAPS) {
503 if (!is_reference()) {
504 return nullptr;
505 }
506 Symbol* name = as_symbol();
507 Klass* k = nullptr;
508 if (failure_mode == ReturnNull) {
509 // Note: SD::resolve_or_null returns null for most failure modes,
510 // but not all. Circularity errors, invalid PDs, etc., throw.
511 k = SystemDictionary::resolve_or_null(name, class_loader, CHECK_NULL);
512 } else if (failure_mode == CachedOrNull) {
513 NoSafepointVerifier nsv; // no loading, now, we mean it!
514 assert(!HAS_PENDING_EXCEPTION, "");
515 k = SystemDictionary::find_instance_klass(THREAD, name, class_loader);
516 // SD::find does not trigger loading, so there should be no throws
517 // Still, bad things can happen, so we CHECK_NULL and ask callers
518 // to do likewise.
519 return k;
520 } else {
521 // The only remaining failure mode is NCDFError.
575 #ifdef ASSERT
576
577 extern bool signature_constants_sane(); // called from basic_types_init()
578
579 bool signature_constants_sane() {
580 // for the lookup table, test every 8-bit code point, and then some:
581 for (int i = -256; i <= 256; i++) {
582 int btcode = 0;
583 switch (i) {
584 #define EACH_SIG(ch, bt, ignore) \
585 case ch: { btcode = bt; break; }
586 SIGNATURE_TYPES_DO(EACH_SIG, ignore)
587 #undef EACH_SIG
588 }
589 int btc = decode_signature_char(i);
590 assert(btc == btcode, "misconfigured table: %d => %d not %d", i, btc, btcode);
591 }
592 return true;
593 }
594
595 bool SignatureVerifier::is_valid_method_signature(Symbol* sig) {
596 const char* method_sig = (const char*)sig->bytes();
597 ssize_t len = sig->utf8_length();
598 ssize_t index = 0;
599 if (method_sig != nullptr && len > 1 && method_sig[index] == JVM_SIGNATURE_FUNC) {
600 ++index;
601 while (index < len && method_sig[index] != JVM_SIGNATURE_ENDFUNC) {
602 ssize_t res = is_valid_type(&method_sig[index], len - index);
603 if (res == -1) {
604 return false;
605 } else {
606 index += res;
607 }
608 }
609 if (index < len && method_sig[index] == JVM_SIGNATURE_ENDFUNC) {
610 // check the return type
611 ++index;
612 return (is_valid_type(&method_sig[index], len - index) == (len - index));
613 }
614 }
615 return false;
616 }
617
618 bool SignatureVerifier::is_valid_type_signature(Symbol* sig) {
619 const char* type_sig = (const char*)sig->bytes();
620 ssize_t len = sig->utf8_length();
621 return (type_sig != nullptr && len >= 1 &&
622 (is_valid_type(type_sig, len) == len));
623 }
624
625 // Checks to see if the type (not to go beyond 'limit') refers to a valid type.
626 // Returns -1 if it is not, or the index of the next character that is not part
627 // of the type. The type encoding may end before 'limit' and that's ok.
628 ssize_t SignatureVerifier::is_valid_type(const char* type, ssize_t limit) {
629 ssize_t index = 0;
630
631 // Iterate over any number of array dimensions
632 while (index < limit && type[index] == JVM_SIGNATURE_ARRAY) ++index;
633 if (index >= limit) {
634 return -1;
635 }
636 switch (type[index]) {
637 case JVM_SIGNATURE_BYTE:
638 case JVM_SIGNATURE_CHAR:
645 case JVM_SIGNATURE_VOID:
646 return index + 1;
647 case JVM_SIGNATURE_CLASS:
648 for (index = index + 1; index < limit; ++index) {
649 char c = type[index];
650 switch (c) {
651 case JVM_SIGNATURE_ENDCLASS:
652 return index + 1;
653 case '\0': case JVM_SIGNATURE_DOT: case JVM_SIGNATURE_ARRAY:
654 return -1;
655 default: ; // fall through
656 }
657 }
658 // fall through
659 default: ; // fall through
660 }
661 return -1;
662 }
663
664 #endif // ASSERT
|
1 /*
2 * Copyright (c) 1997, 2026, 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 "asm/assembler.hpp"
26 #include "classfile/symbolTable.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/vmSymbols.hpp"
29 #include "memory/oopFactory.hpp"
30 #include "memory/resourceArea.hpp"
31 #include "memory/universe.hpp"
32 #include "oops/inlineKlass.inline.hpp"
33 #include "oops/instanceKlass.hpp"
34 #include "oops/klass.inline.hpp"
35 #include "oops/oop.inline.hpp"
36 #include "oops/symbol.hpp"
37 #include "oops/typeArrayKlass.hpp"
38 #include "runtime/fieldDescriptor.inline.hpp"
39 #include "runtime/handles.inline.hpp"
40 #include "runtime/interfaceSupport.inline.hpp"
41 #include "runtime/safepointVerifiers.hpp"
42 #include "runtime/sharedRuntime.hpp"
43 #include "runtime/signature.hpp"
44
45 // Implementation of SignatureIterator
46
47 // Signature syntax:
48 //
49 // Signature = "(" {Parameter} ")" ReturnType.
50 // Parameter = FieldType.
51 // ReturnType = FieldType | "V".
52 // FieldType = "B" | "C" | "D" | "F" | "I" | "J" | "S" | "Z" | "L" ClassName ";" | "[" FieldType.
53 // ClassName = string.
54
55 // The ClassName string can be any JVM-style UTF8 string except:
56 // - an empty string (the empty string is never a name of any kind)
57 // - a string which begins or ends with slash '/' (the package separator)
58 // - a string which contains adjacent slashes '//' (no empty package names)
59 // - a string which contains a semicolon ';' (the end-delimiter)
60 // - a string which contains a left bracket '[' (the array marker)
484 if (name->equals(symbol_chars, len)) {
485 return name;
486 }
487
488 // Save names for cleaning up reference count at the end of
489 // SignatureStream scope.
490 name = SymbolTable::new_symbol(symbol_chars, len);
491
492 // Only allocate the GrowableArray for the _names buffer if more than
493 // one name is being processed in the signature.
494 if (!_previous_name->is_permanent()) {
495 if (_names == nullptr) {
496 _names = new GrowableArray<Symbol*>(10);
497 }
498 _names->push(_previous_name);
499 }
500 _previous_name = name;
501 return name;
502 }
503
504 InlineKlass* SignatureStream::as_inline_klass(InstanceKlass* holder) {
505 ThreadInVMfromUnknown tiv;
506 JavaThread* THREAD = JavaThread::current();
507 HandleMark hm(THREAD);
508 Handle class_loader(THREAD, holder->class_loader());
509 Klass* k = as_klass(class_loader, SignatureStream::CachedOrNull, THREAD);
510 assert(!HAS_PENDING_EXCEPTION, "Should never throw");
511 if (k != nullptr && k->is_inline_klass()) {
512 return InlineKlass::cast(k);
513 } else {
514 return nullptr;
515 }
516 }
517
518 Klass* SignatureStream::as_klass(Handle class_loader, FailureMode failure_mode, TRAPS) {
519 if (!is_reference()) {
520 return nullptr;
521 }
522 Symbol* name = as_symbol();
523 Klass* k = nullptr;
524 if (failure_mode == ReturnNull) {
525 // Note: SD::resolve_or_null returns null for most failure modes,
526 // but not all. Circularity errors, invalid PDs, etc., throw.
527 k = SystemDictionary::resolve_or_null(name, class_loader, CHECK_NULL);
528 } else if (failure_mode == CachedOrNull) {
529 NoSafepointVerifier nsv; // no loading, now, we mean it!
530 assert(!HAS_PENDING_EXCEPTION, "");
531 k = SystemDictionary::find_instance_klass(THREAD, name, class_loader);
532 // SD::find does not trigger loading, so there should be no throws
533 // Still, bad things can happen, so we CHECK_NULL and ask callers
534 // to do likewise.
535 return k;
536 } else {
537 // The only remaining failure mode is NCDFError.
591 #ifdef ASSERT
592
593 extern bool signature_constants_sane(); // called from basic_types_init()
594
595 bool signature_constants_sane() {
596 // for the lookup table, test every 8-bit code point, and then some:
597 for (int i = -256; i <= 256; i++) {
598 int btcode = 0;
599 switch (i) {
600 #define EACH_SIG(ch, bt, ignore) \
601 case ch: { btcode = bt; break; }
602 SIGNATURE_TYPES_DO(EACH_SIG, ignore)
603 #undef EACH_SIG
604 }
605 int btc = decode_signature_char(i);
606 assert(btc == btcode, "misconfigured table: %d => %d not %d", i, btc, btcode);
607 }
608 return true;
609 }
610
611 bool SignatureVerifier::is_valid_method_signature(const Symbol* sig) {
612 const char* method_sig = (const char*)sig->bytes();
613 ssize_t len = sig->utf8_length();
614 ssize_t index = 0;
615 if (method_sig != nullptr && len > 1 && method_sig[index] == JVM_SIGNATURE_FUNC) {
616 ++index;
617 while (index < len && method_sig[index] != JVM_SIGNATURE_ENDFUNC) {
618 ssize_t res = is_valid_type(&method_sig[index], len - index);
619 if (res == -1) {
620 return false;
621 } else {
622 index += res;
623 }
624 }
625 if (index < len && method_sig[index] == JVM_SIGNATURE_ENDFUNC) {
626 // check the return type
627 ++index;
628 return (is_valid_type(&method_sig[index], len - index) == (len - index));
629 }
630 }
631 return false;
632 }
633
634 bool SignatureVerifier::is_valid_type_signature(const Symbol* sig) {
635 const char* type_sig = (const char*)sig->bytes();
636 ssize_t len = sig->utf8_length();
637 return (type_sig != nullptr && len >= 1 &&
638 (is_valid_type(type_sig, len) == len));
639 }
640
641 // Checks to see if the type (not to go beyond 'limit') refers to a valid type.
642 // Returns -1 if it is not, or the index of the next character that is not part
643 // of the type. The type encoding may end before 'limit' and that's ok.
644 ssize_t SignatureVerifier::is_valid_type(const char* type, ssize_t limit) {
645 ssize_t index = 0;
646
647 // Iterate over any number of array dimensions
648 while (index < limit && type[index] == JVM_SIGNATURE_ARRAY) ++index;
649 if (index >= limit) {
650 return -1;
651 }
652 switch (type[index]) {
653 case JVM_SIGNATURE_BYTE:
654 case JVM_SIGNATURE_CHAR:
661 case JVM_SIGNATURE_VOID:
662 return index + 1;
663 case JVM_SIGNATURE_CLASS:
664 for (index = index + 1; index < limit; ++index) {
665 char c = type[index];
666 switch (c) {
667 case JVM_SIGNATURE_ENDCLASS:
668 return index + 1;
669 case '\0': case JVM_SIGNATURE_DOT: case JVM_SIGNATURE_ARRAY:
670 return -1;
671 default: ; // fall through
672 }
673 }
674 // fall through
675 default: ; // fall through
676 }
677 return -1;
678 }
679
680 #endif // ASSERT
681
682 // Adds an argument to the signature
683 void SigEntry::add_entry(GrowableArray<SigEntry>* sig, BasicType bt, Symbol* name, int offset, bool null_marker, bool vt_oop) {
684 sig->append(SigEntry(bt, offset, name, null_marker, vt_oop));
685 if (bt == T_LONG || bt == T_DOUBLE) {
686 sig->append(SigEntry(T_VOID, offset, name, false, false)); // Longs and doubles take two stack slots
687 }
688 }
689 void SigEntry::add_null_marker(GrowableArray<SigEntry>* sig, Symbol* name, int offset) {
690 sig->append(SigEntry(T_BOOLEAN, offset, name, true, false));
691 }
692
693 // Returns true if the argument at index 'i' is not an inline type delimiter
694 bool SigEntry::skip_value_delimiters(const GrowableArray<SigEntry>* sig, int i) {
695 return (sig->at(i)._bt != T_METADATA &&
696 (sig->at(i)._bt != T_VOID || sig->at(i-1)._bt == T_LONG || sig->at(i-1)._bt == T_DOUBLE));
697 }
698
699 // Fill basic type array from signature array
700 int SigEntry::fill_sig_bt(const GrowableArray<SigEntry>* sig, BasicType* sig_bt) {
701 int count = 0;
702 for (int i = 0; i < sig->length(); i++) {
703 if (skip_value_delimiters(sig, i)) {
704 sig_bt[count++] = sig->at(i)._bt;
705 }
706 }
707 return count;
708 }
709
710 // Create a temporary symbol from the signature array
711 TempNewSymbol SigEntry::create_symbol(const GrowableArray<SigEntry>* sig) {
712 ResourceMark rm;
713 int length = sig->length();
714 char* sig_str = NEW_RESOURCE_ARRAY(char, 2*length + 3);
715 int idx = 0;
716 sig_str[idx++] = '(';
717 for (int i = 0; i < length; i++) {
718 BasicType bt = sig->at(i)._bt;
719 if (bt == T_METADATA || bt == T_VOID) {
720 // Ignore
721 } else {
722 if (bt == T_ARRAY) {
723 bt = T_OBJECT; // We don't know the element type, treat as Object
724 }
725 sig_str[idx++] = type2char(bt);
726 if (bt == T_OBJECT) {
727 sig_str[idx++] = ';';
728 }
729 }
730 }
731 sig_str[idx++] = ')';
732 // Add a dummy return type. It won't be used but SignatureStream needs it.
733 sig_str[idx++] = 'V';
734 sig_str[idx++] = '\0';
735 return SymbolTable::new_symbol(sig_str);
736 }
737
738 void SigEntry::print_on(outputStream* st) const {
739 st->print("SigEntry: type=%d offset=%d null_marker=%d ", _bt, _offset, _null_marker);
740 if (_name != nullptr) {
741 _name->print_on(st);
742 } else {
743 st->print("name=nullptr");
744 }
745 }
|