diff -r 4ebc2e2fb97c -r 71c04702a3d5 src/hotspot/share/utilities/elfFuncDescTable.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/hotspot/share/utilities/elfFuncDescTable.cpp Tue Sep 12 19:03:39 2017 +0200 @@ -0,0 +1,104 @@ +/* + * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved. + * Copyright (c) 2012, 2013 SAP SE. 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 "utilities/elfFuncDescTable.hpp" + +ElfFuncDescTable::ElfFuncDescTable(FILE* file, Elf_Shdr shdr, int index) { + assert(file, "null file handle"); + // The actual function address (i.e. function entry point) is always the + // first value in the function descriptor (on IA64 and PPC64 they look as follows): + // PPC64: [function entry point, TOC pointer, environment pointer] + // IA64 : [function entry point, GP (global pointer) value] + // Unfortunately 'shdr.sh_entsize' doesn't always seem to contain this size (it's zero on PPC64) so we can't assert + // assert(IA64_ONLY(2) PPC64_ONLY(3) * sizeof(address) == shdr.sh_entsize, "Size mismatch for '.opd' section entries"); + + m_funcDescs = NULL; + m_file = file; + m_index = index; + m_status = NullDecoder::no_error; + + // try to load the function descriptor table + long cur_offset = ftell(file); + if (cur_offset != -1) { + // call malloc so we can back up if memory allocation fails. + m_funcDescs = (address*)os::malloc(shdr.sh_size, mtInternal); + if (m_funcDescs) { + if (fseek(file, shdr.sh_offset, SEEK_SET) || + fread((void*)m_funcDescs, shdr.sh_size, 1, file) != 1 || + fseek(file, cur_offset, SEEK_SET)) { + m_status = NullDecoder::file_invalid; + os::free(m_funcDescs); + m_funcDescs = NULL; + } + } + if (!NullDecoder::is_error(m_status)) { + memcpy(&m_shdr, &shdr, sizeof(Elf_Shdr)); + } + } else { + m_status = NullDecoder::file_invalid; + } +} + +ElfFuncDescTable::~ElfFuncDescTable() { + if (m_funcDescs != NULL) { + os::free(m_funcDescs); + } +} + +address ElfFuncDescTable::lookup(Elf_Word index) { + if (NullDecoder::is_error(m_status)) { + return NULL; + } + + if (m_funcDescs != NULL) { + if (m_shdr.sh_size > 0 && m_shdr.sh_addr <= index && index <= m_shdr.sh_addr + m_shdr.sh_size) { + // Notice that 'index' is a byte-offset into the function descriptor table. + return m_funcDescs[(index - m_shdr.sh_addr) / sizeof(address)]; + } + return NULL; + } else { + long cur_pos; + address addr; + if (!(m_shdr.sh_size > 0 && m_shdr.sh_addr <= index && index <= m_shdr.sh_addr + m_shdr.sh_size)) { + // don't put the whole decoder in error mode if we just tried a wrong index + return NULL; + } + if ((cur_pos = ftell(m_file)) == -1 || + fseek(m_file, m_shdr.sh_offset + index - m_shdr.sh_addr, SEEK_SET) || + fread(&addr, sizeof(addr), 1, m_file) != 1 || + fseek(m_file, cur_pos, SEEK_SET)) { + m_status = NullDecoder::file_invalid; + return NULL; + } + return addr; + } +} + +#endif // !_WINDOWS && !__APPLE__