| /* |
| * Copyright (c) 1997, 2018, 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" |
| |
| #if !defined(_WINDOWS) && !defined(__APPLE__) |
| |
| #include "jvm.h" |
| #include "memory/allocation.inline.hpp" |
| #include "runtime/os.hpp" |
| #include "utilities/elfStringTable.hpp" |
| |
| // We will try to load whole string table into memory if we can. |
| // Otherwise, fallback to more expensive file operation. |
| ElfStringTable::ElfStringTable(FILE* const file, Elf_Shdr& shdr, int index) : |
| _section(file, shdr), _index(index), _fd(file), _next(NULL) { |
| _status = _section.status(); |
| } |
| |
| ElfStringTable::~ElfStringTable() { |
| if (_next != NULL) { |
| delete _next; |
| } |
| } |
| |
| bool ElfStringTable::string_at(size_t pos, char* buf, int buflen) { |
| if (NullDecoder::is_error(get_status())) { |
| return false; |
| } |
| |
| assert(buflen > 0, "no buffer"); |
| if (pos >= _section.section_header()->sh_size) { |
| return false; |
| } |
| |
| const char* data = (const char*)_section.section_data(); |
| if (data != NULL) { |
| jio_snprintf(buf, buflen, "%s", data + pos); |
| return true; |
| } else { // no cache data, read from file instead |
| const Elf_Shdr* const shdr = _section.section_header(); |
| MarkedFileReader mfd(_fd); |
| if (mfd.has_mark() && |
| mfd.set_position(shdr->sh_offset + pos) && |
| mfd.read((void*)buf, size_t(buflen))) { |
| buf[buflen - 1] = '\0'; |
| return true; |
| } else { |
| // put it in error state to avoid retry |
| _status = NullDecoder::file_invalid; |
| return false; |
| } |
| } |
| } |
| |
| #endif // !_WINDOWS && !__APPLE__ |