jdk8-mips64-public/hotspot: comparison src/share/vm/utilities/elfFile.cpp

--1:000000000000
+:f90c822e73f8
+/*
+* Copyright (c) 1997, 2013, 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 <string.h>
+#include <stdio.h>
+#include <limits.h>
+#include <new>
+#include "memory/allocation.inline.hpp"
+#include "utilities/decoder.hpp"
+#include "utilities/elfFile.hpp"
+#include "utilities/elfFuncDescTable.hpp"
+#include "utilities/elfStringTable.hpp"
+#include "utilities/elfSymbolTable.hpp"
+ElfFile::ElfFile(const char* filepath) {
+assert(filepath, "null file path");
+memset(&m_elfHdr, 0, sizeof(m_elfHdr));
+m_string_tables = NULL;
+m_symbol_tables = NULL;
+m_funcDesc_table = NULL;
+m_next = NULL;
+m_status = NullDecoder::no_error;
+int len = strlen(filepath) + 1;
+m_filepath = (const char*)os::malloc(len * sizeof(char), mtInternal);
+if (m_filepath != NULL) {
+strcpy((char*)m_filepath, filepath);
+m_file = fopen(filepath, "r");
+if (m_file != NULL) {
+load_tables();
+} else {
+m_status = NullDecoder::file_not_found;
+}
+} else {
+m_status = NullDecoder::out_of_memory;
+}
+}
+ElfFile::~ElfFile() {
+if (m_string_tables != NULL) {
+delete m_string_tables;
+}
+if (m_symbol_tables != NULL) {
+delete m_symbol_tables;
+}
+if (m_file != NULL) {
+fclose(m_file);
+}
+if (m_filepath != NULL) {
+os::free((void*)m_filepath);
+}
+if (m_next != NULL) {
+delete m_next;
+}
+};
+//Check elf header to ensure the file is valid.
+bool ElfFile::is_elf_file(Elf_Ehdr& hdr) {
+return (ELFMAG0 == hdr.e_ident[EI_MAG0] &&
+ELFMAG1 == hdr.e_ident[EI_MAG1] &&
+ELFMAG2 == hdr.e_ident[EI_MAG2] &&
+ELFMAG3 == hdr.e_ident[EI_MAG3] &&
+ELFCLASSNONE != hdr.e_ident[EI_CLASS] &&
+ELFDATANONE != hdr.e_ident[EI_DATA]);
+}
+bool ElfFile::load_tables() {
+assert(m_file, "file not open");
+assert(!NullDecoder::is_error(m_status), "already in error");
+// read elf file header
+if (fread(&m_elfHdr, sizeof(m_elfHdr), 1, m_file) != 1) {
+m_status = NullDecoder::file_invalid;
+return false;
+}
+if (!is_elf_file(m_elfHdr)) {
+m_status = NullDecoder::file_invalid;
+return false;
+}
+// walk elf file's section headers, and load string tables
+Elf_Shdr shdr;
+if (!fseek(m_file, m_elfHdr.e_shoff, SEEK_SET)) {
+if (NullDecoder::is_error(m_status)) return false;
+for (int index = 0; index < m_elfHdr.e_shnum; index ++) {
+if (fread((void*)&shdr, sizeof(Elf_Shdr), 1, m_file) != 1) {
+m_status = NullDecoder::file_invalid;
+return false;
+}
+if (shdr.sh_type == SHT_STRTAB) {
+// string tables
+ElfStringTable* table = new (std::nothrow) ElfStringTable(m_file, shdr, index);
+if (table == NULL) {
+m_status = NullDecoder::out_of_memory;
+return false;
+}
+add_string_table(table);
+} else if (shdr.sh_type == SHT_SYMTAB || shdr.sh_type == SHT_DYNSYM) {
+// symbol tables
+ElfSymbolTable* table = new (std::nothrow) ElfSymbolTable(m_file, shdr);
+if (table == NULL) {
+m_status = NullDecoder::out_of_memory;
+return false;
+}
+add_symbol_table(table);
+}
+}
+#if defined(PPC64) && !defined(ABI_ELFv2)
+// Now read the .opd section wich contains the PPC64 function descriptor table.
+// The .opd section is only available on PPC64 (see for example:
+// http://refspecs.linuxfoundation.org/LSB_3.1.1/LSB-Core-PPC64/LSB-Core-PPC64/specialsections.html)
+// so this code should do no harm on other platforms but because of performance reasons we only
+// execute it on PPC64 platforms.
+// Notice that we can only find the .opd section after we have successfully read in the string
+// tables in the previous loop, because we need to query the name of each section which is
+// contained in one of the string tables (i.e. the one with the index m_elfHdr.e_shstrndx).
+// Reset the file pointer
+if (fseek(m_file, m_elfHdr.e_shoff, SEEK_SET)) {
+m_status = NullDecoder::file_invalid;
+return false;
+}
+for (int index = 0; index < m_elfHdr.e_shnum; index ++) {
+if (fread((void*)&shdr, sizeof(Elf_Shdr), 1, m_file) != 1) {
+m_status = NullDecoder::file_invalid;
+return false;
+}
+if (m_elfHdr.e_shstrndx != SHN_UNDEF && shdr.sh_type == SHT_PROGBITS) {
+ElfStringTable* string_table = get_string_table(m_elfHdr.e_shstrndx);
+if (string_table == NULL) {
+m_status = NullDecoder::file_invalid;
+return false;
+}
+char buf[8]; // '8' is enough because we only want to read ".opd"
+if (string_table->string_at(shdr.sh_name, buf, sizeof(buf)) && !strncmp(".opd", buf, 4)) {
+m_funcDesc_table = new (std::nothrow) ElfFuncDescTable(m_file, shdr, index);
+if (m_funcDesc_table == NULL) {
+m_status = NullDecoder::out_of_memory;
+return false;
+}
+break;
+}
+}
+}
+#endif
+}
+return true;
+}
+bool ElfFile::decode(address addr, char* buf, int buflen, int* offset) {
+// something already went wrong, just give up
+if (NullDecoder::is_error(m_status)) {
+return false;
+}
+ElfSymbolTable* symbol_table = m_symbol_tables;
+int string_table_index;
+int pos_in_string_table;
+int off = INT_MAX;
+bool found_symbol = false;
+while (symbol_table != NULL) {
+if (symbol_table->lookup(addr, &string_table_index, &pos_in_string_table, &off, m_funcDesc_table)) {
+found_symbol = true;
+break;
+}
+symbol_table = symbol_table->m_next;
+}
+if (!found_symbol) return false;
+ElfStringTable* string_table = get_string_table(string_table_index);
+if (string_table == NULL) {
+m_status = NullDecoder::file_invalid;
+return false;
+}
+if (offset) *offset = off;
+return string_table->string_at(pos_in_string_table, buf, buflen);
+}
+void ElfFile::add_symbol_table(ElfSymbolTable* table) {
+if (m_symbol_tables == NULL) {
+m_symbol_tables = table;
+} else {
+table->m_next = m_symbol_tables;
+m_symbol_tables = table;
+}
+}
+void ElfFile::add_string_table(ElfStringTable* table) {
+if (m_string_tables == NULL) {
+m_string_tables = table;
+} else {
+table->m_next = m_string_tables;
+m_string_tables = table;
+}
+}
+ElfStringTable* ElfFile::get_string_table(int index) {
+ElfStringTable* p = m_string_tables;
+while (p != NULL) {
+if (p->index() == index) return p;
+p = p->m_next;
+}
+return NULL;
+}
+#ifdef LINUX
+bool ElfFile::specifies_noexecstack() {
+Elf_Phdr phdr;
+if (!m_file)  return true;
+if (!fseek(m_file, m_elfHdr.e_phoff, SEEK_SET)) {
+for (int index = 0; index < m_elfHdr.e_phnum; index ++) {
+if (fread((void*)&phdr, sizeof(Elf_Phdr), 1, m_file) != 1) {
+m_status = NullDecoder::file_invalid;
+return false;
+}
+if (phdr.p_type == PT_GNU_STACK) {
+if (phdr.p_flags == (PF_R | PF_W))  {
+return true;
+} else {
+return false;
+}
+}
+}
+}
+return false;
+}
+#endif
+#endif // !_WINDOWS && !__APPLE__

Mercurial > jdk8-mips64-public > hotspot / file comparison

comparison: src/share/vm/utilities/elfFile.cpp

src/share/vm/utilities/elfFile.cpp