--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/oops/symbol.cpp Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,268 @@
+/*
+ * Copyright (c) 1997, 2017, 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 "classfile/altHashing.hpp"
+#include "classfile/classLoaderData.hpp"
+#include "logging/log.hpp"
+#include "logging/logStream.hpp"
+#include "memory/allocation.inline.hpp"
+#include "memory/resourceArea.hpp"
+#include "oops/symbol.hpp"
+#include "runtime/atomic.hpp"
+#include "runtime/os.hpp"
+
+Symbol::Symbol(const u1* name, int length, int refcount) {
+ _refcount = refcount;
+ _length = length;
+ _identity_hash = (short)os::random();
+ for (int i = 0; i < _length; i++) {
+ byte_at_put(i, name[i]);
+ }
+}
+
+void* Symbol::operator new(size_t sz, int len, TRAPS) throw() {
+ int alloc_size = size(len)*wordSize;
+ address res = (address) AllocateHeap(alloc_size, mtSymbol);
+ return res;
+}
+
+void* Symbol::operator new(size_t sz, int len, Arena* arena, TRAPS) throw() {
+ int alloc_size = size(len)*wordSize;
+ address res = (address)arena->Amalloc_4(alloc_size);
+ return res;
+}
+
+void Symbol::operator delete(void *p) {
+ assert(((Symbol*)p)->refcount() == 0, "should not call this");
+ FreeHeap(p);
+}
+
+// ------------------------------------------------------------------
+// Symbol::starts_with
+//
+// Tests if the symbol starts with the specified prefix of the given
+// length.
+bool Symbol::starts_with(const char* prefix, int len) const {
+ if (len > utf8_length()) return false;
+ while (len-- > 0) {
+ if (prefix[len] != (char) byte_at(len))
+ return false;
+ }
+ assert(len == -1, "we should be at the beginning");
+ return true;
+}
+
+
+// ------------------------------------------------------------------
+// Symbol::index_of
+//
+// Finds if the given string is a substring of this symbol's utf8 bytes.
+// Return -1 on failure. Otherwise return the first index where str occurs.
+int Symbol::index_of_at(int i, const char* str, int len) const {
+ assert(i >= 0 && i <= utf8_length(), "oob");
+ if (len <= 0) return 0;
+ char first_char = str[0];
+ address bytes = (address) ((Symbol*)this)->base();
+ address limit = bytes + utf8_length() - len; // inclusive limit
+ address scan = bytes + i;
+ if (scan > limit)
+ return -1;
+ for (; scan <= limit; scan++) {
+ scan = (address) memchr(scan, first_char, (limit + 1 - scan));
+ if (scan == NULL)
+ return -1; // not found
+ assert(scan >= bytes+i && scan <= limit, "scan oob");
+ if (memcmp(scan, str, len) == 0)
+ return (int)(scan - bytes);
+ }
+ return -1;
+}
+
+
+char* Symbol::as_C_string(char* buf, int size) const {
+ if (size > 0) {
+ int len = MIN2(size - 1, utf8_length());
+ for (int i = 0; i < len; i++) {
+ buf[i] = byte_at(i);
+ }
+ buf[len] = '\0';
+ }
+ return buf;
+}
+
+char* Symbol::as_C_string() const {
+ int len = utf8_length();
+ char* str = NEW_RESOURCE_ARRAY(char, len + 1);
+ return as_C_string(str, len + 1);
+}
+
+char* Symbol::as_C_string_flexible_buffer(Thread* t,
+ char* buf, int size) const {
+ char* str;
+ int len = utf8_length();
+ int buf_len = len + 1;
+ if (size < buf_len) {
+ str = NEW_RESOURCE_ARRAY(char, buf_len);
+ } else {
+ str = buf;
+ }
+ return as_C_string(str, buf_len);
+}
+
+void Symbol::print_utf8_on(outputStream* st) const {
+ st->print("%s", as_C_string());
+}
+
+void Symbol::print_symbol_on(outputStream* st) const {
+ char *s;
+ st = st ? st : tty;
+ {
+ // ResourceMark may not affect st->print(). If st is a string
+ // stream it could resize, using the same resource arena.
+ ResourceMark rm;
+ s = as_quoted_ascii();
+ s = os::strdup(s);
+ }
+ if (s == NULL) {
+ st->print("(null)");
+ } else {
+ st->print("%s", s);
+ os::free(s);
+ }
+}
+
+char* Symbol::as_quoted_ascii() const {
+ const char *ptr = (const char *)&_body[0];
+ int quoted_length = UTF8::quoted_ascii_length(ptr, utf8_length());
+ char* result = NEW_RESOURCE_ARRAY(char, quoted_length + 1);
+ UTF8::as_quoted_ascii(ptr, utf8_length(), result, quoted_length + 1);
+ return result;
+}
+
+jchar* Symbol::as_unicode(int& length) const {
+ Symbol* this_ptr = (Symbol*)this;
+ length = UTF8::unicode_length((char*)this_ptr->bytes(), utf8_length());
+ jchar* result = NEW_RESOURCE_ARRAY(jchar, length);
+ if (length > 0) {
+ UTF8::convert_to_unicode((char*)this_ptr->bytes(), result, length);
+ }
+ return result;
+}
+
+const char* Symbol::as_klass_external_name(char* buf, int size) const {
+ if (size > 0) {
+ char* str = as_C_string(buf, size);
+ int length = (int)strlen(str);
+ // Turn all '/'s into '.'s (also for array klasses)
+ for (int index = 0; index < length; index++) {
+ if (str[index] == '/') {
+ str[index] = '.';
+ }
+ }
+ return str;
+ } else {
+ return buf;
+ }
+}
+
+const char* Symbol::as_klass_external_name() const {
+ char* str = as_C_string();
+ int length = (int)strlen(str);
+ // Turn all '/'s into '.'s (also for array klasses)
+ for (int index = 0; index < length; index++) {
+ if (str[index] == '/') {
+ str[index] = '.';
+ }
+ }
+ return str;
+}
+
+// Alternate hashing for unbalanced symbol tables.
+unsigned int Symbol::new_hash(juint seed) {
+ ResourceMark rm;
+ // Use alternate hashing algorithm on this symbol.
+ return AltHashing::murmur3_32(seed, (const jbyte*)as_C_string(), utf8_length());
+}
+
+void Symbol::increment_refcount() {
+ // Only increment the refcount if non-negative. If negative either
+ // overflow has occurred or it is a permanent symbol in a read only
+ // shared archive.
+ if (_refcount >= 0) { // not a permanent symbol
+ Atomic::inc(&_refcount);
+ NOT_PRODUCT(Atomic::inc(&_total_count);)
+ }
+}
+
+void Symbol::decrement_refcount() {
+ if (_refcount >= 0) { // not a permanent symbol
+ short new_value = Atomic::add(short(-1), &_refcount);
+#ifdef ASSERT
+ if (new_value == -1) { // we have transitioned from 0 -> -1
+ print();
+ assert(false, "reference count underflow for symbol");
+ }
+#endif
+ (void)new_value;
+ }
+}
+
+void Symbol::metaspace_pointers_do(MetaspaceClosure* it) {
+ if (log_is_enabled(Trace, cds)) {
+ LogStream trace_stream(Log(cds)::trace());
+ trace_stream.print("Iter(Symbol): %p ", this);
+ print_value_on(&trace_stream);
+ trace_stream.cr();
+ }
+}
+
+void Symbol::print_on(outputStream* st) const {
+ if (this == NULL) {
+ st->print_cr("NULL");
+ } else {
+ st->print("Symbol: '");
+ print_symbol_on(st);
+ st->print("'");
+ st->print(" count %d", refcount());
+ }
+}
+
+// The print_value functions are present in all builds, to support the
+// disassembler and error reporting.
+void Symbol::print_value_on(outputStream* st) const {
+ if (this == NULL) {
+ st->print("NULL");
+ } else {
+ st->print("'");
+ for (int i = 0; i < utf8_length(); i++) {
+ st->print("%c", byte_at(i));
+ }
+ st->print("'");
+ }
+}
+
+// SymbolTable prints this in its statistics
+NOT_PRODUCT(int Symbol::_total_count = 0;)