diff -r 4ebc2e2fb97c -r 71c04702a3d5 src/hotspot/share/utilities/elfStringTable.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/hotspot/share/utilities/elfStringTable.cpp Tue Sep 12 19:03:39 2017 +0200 @@ -0,0 +1,91 @@ +/* + * 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" + +#if !defined(_WINDOWS) && !defined(__APPLE__) + +#include "memory/allocation.inline.hpp" +#include "prims/jvm.h" +#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* file, Elf_Shdr shdr, int index) { + assert(file, "null file handle"); + m_table = NULL; + m_index = index; + m_next = NULL; + m_file = file; + m_status = NullDecoder::no_error; + + // try to load the string table + long cur_offset = ftell(file); + m_table = (char*)os::malloc(sizeof(char) * shdr.sh_size, mtInternal); + if (m_table != NULL) { + // if there is an error, mark the error + if (fseek(file, shdr.sh_offset, SEEK_SET) || + fread((void*)m_table, shdr.sh_size, 1, file) != 1 || + fseek(file, cur_offset, SEEK_SET)) { + m_status = NullDecoder::file_invalid; + os::free((void*)m_table); + m_table = NULL; + } + } else { + memcpy(&m_shdr, &shdr, sizeof(Elf_Shdr)); + } +} + +ElfStringTable::~ElfStringTable() { + if (m_table != NULL) { + os::free((void*)m_table); + } + + if (m_next != NULL) { + delete m_next; + } +} + +bool ElfStringTable::string_at(int pos, char* buf, int buflen) { + if (NullDecoder::is_error(m_status)) { + return false; + } + if (m_table != NULL) { + jio_snprintf(buf, buflen, "%s", (const char*)(m_table + pos)); + return true; + } else { + long cur_pos = ftell(m_file); + if (cur_pos == -1 || + fseek(m_file, m_shdr.sh_offset + pos, SEEK_SET) || + fread(buf, 1, buflen, m_file) <= 0 || + fseek(m_file, cur_pos, SEEK_SET)) { + m_status = NullDecoder::file_invalid; + return false; + } + return true; + } +} + +#endif // !_WINDOWS && !__APPLE__