--- a/hotspot/src/share/vm/classfile/imageFile.cpp Fri Sep 18 14:21:34 2015 -0700
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,546 +0,0 @@
-/*
- * Copyright (c) 2015, 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/imageDecompressor.hpp"
-#include "classfile/imageFile.hpp"
-#include "memory/resourceArea.hpp"
-#include "runtime/mutex.hpp"
-#include "runtime/mutexLocker.hpp"
-#include "runtime/os.inline.hpp"
-#include "utilities/endian.hpp"
-#include "utilities/growableArray.hpp"
-
-// Image files are an alternate file format for storing classes and resources. The
-// goal is to supply file access which is faster and smaller than the jar format.
-//
-// (More detailed nodes in the header.)
-//
-
-// Compute the Perfect Hashing hash code for the supplied UTF-8 string.
-s4 ImageStrings::hash_code(const char* string, s4 seed) {
- // Access bytes as unsigned.
- u1* bytes = (u1*)string;
- // Compute hash code.
- for (u1 byte = *bytes++; byte; byte = *bytes++) {
- seed = (seed * HASH_MULTIPLIER) ^ byte;
- }
- // Ensure the result is not signed.
- return seed & 0x7FFFFFFF;
-}
-
-// Match up a string in a perfect hash table. Result still needs validation
-// for precise match (false positive.)
-s4 ImageStrings::find(Endian* endian, const char* name, s4* redirect, u4 length) {
- // If the table is empty, then short cut.
- if (redirect == NULL || length == 0) {
- return NOT_FOUND;
- }
- // Compute the basic perfect hash for name.
- s4 hash_code = ImageStrings::hash_code(name);
- // Modulo table size.
- s4 index = hash_code % length;
- // Get redirect entry.
- // value == 0 then not found
- // value < 0 then -1 - value is true index
- // value > 0 then value is seed for recomputing hash.
- s4 value = endian->get(redirect[index]);
- // if recompute is required.
- if (value > 0) {
- // Entry collision value, need to recompute hash.
- hash_code = ImageStrings::hash_code(name, value);
- // Modulo table size.
- return hash_code % length;
- } else if (value < 0) {
- // Compute direct index.
- return -1 - value;
- }
- // No entry found.
- return NOT_FOUND;
-}
-
-// Test to see if UTF-8 string begins with the start UTF-8 string. If so,
-// return non-NULL address of remaining portion of string. Otherwise, return
-// NULL. Used to test sections of a path without copying from image string
-// table.
-const char* ImageStrings::starts_with(const char* string, const char* start) {
- char ch1, ch2;
- // Match up the strings the best we can.
- while ((ch1 = *string) && (ch2 = *start)) {
- if (ch1 != ch2) {
- // Mismatch, return NULL.
- return NULL;
- }
- // Next characters.
- string++, start++;
- }
- // Return remainder of string.
- return string;
-}
-
-// Inflates the attribute stream into individual values stored in the long
-// array _attributes. This allows an attribute value to be quickly accessed by
-// direct indexing. Unspecified values default to zero (from constructor.)
-void ImageLocation::set_data(u1* data) {
- // Deflate the attribute stream into an array of attributes.
- u1 byte;
- // Repeat until end header is found.
- while ((byte = *data)) {
- // Extract kind from header byte.
- u1 kind = attribute_kind(byte);
- guarantee(kind < ATTRIBUTE_COUNT, "invalid image location attribute");
- // Extract length of data (in bytes).
- u1 n = attribute_length(byte);
- // Read value (most significant first.)
- _attributes[kind] = attribute_value(data + 1, n);
- // Position to next attribute by skipping attribute header and data bytes.
- data += n + 1;
- }
-}
-
-// Zero all attribute values.
-void ImageLocation::clear_data() {
- // Set defaults to zero.
- memset(_attributes, 0, sizeof(_attributes));
-}
-
-// ImageModuleData constructor maps out sub-tables for faster access.
-ImageModuleData::ImageModuleData(const ImageFileReader* image_file,
- const char* module_data_name) :
- _image_file(image_file),
- _endian(image_file->endian()),
- _strings(image_file->get_strings()) {
- // Retrieve the resource containing the module data for the image file.
- ImageLocation location;
- bool found = image_file->find_location(module_data_name, location);
- guarantee(found, "missing module data");
- u8 data_size = location.get_attribute(ImageLocation::ATTRIBUTE_UNCOMPRESSED);
- _data = (u1*)NEW_C_HEAP_ARRAY(char, data_size, mtClass);
- _image_file->get_resource(location, _data);
- // Map out the header.
- _header = (Header*)_data;
- // Get the package to module entry count.
- u4 ptm_count = _header->ptm_count(_endian);
- // Get the module to package entry count.
- u4 mtp_count = _header->mtp_count(_endian);
- // Compute the offset of the package to module perfect hash redirect.
- u4 ptm_redirect_offset = sizeof(Header);
- // Compute the offset of the package to module data.
- u4 ptm_data_offset = ptm_redirect_offset + ptm_count * sizeof(s4);
- // Compute the offset of the module to package perfect hash redirect.
- u4 mtp_redirect_offset = ptm_data_offset + ptm_count * sizeof(PTMData);
- // Compute the offset of the module to package data.
- u4 mtp_data_offset = mtp_redirect_offset + mtp_count * sizeof(s4);
- // Compute the offset of the module to package tables.
- u4 mtp_packages_offset = mtp_data_offset + mtp_count * sizeof(MTPData);
- // Compute the address of the package to module perfect hash redirect.
- _ptm_redirect = (s4*)(_data + ptm_redirect_offset);
- // Compute the address of the package to module data.
- _ptm_data = (PTMData*)(_data + ptm_data_offset);
- // Compute the address of the module to package perfect hash redirect.
- _mtp_redirect = (s4*)(_data + mtp_redirect_offset);
- // Compute the address of the module to package data.
- _mtp_data = (MTPData*)(_data + mtp_data_offset);
- // Compute the address of the module to package tables.
- _mtp_packages = (s4*)(_data + mtp_packages_offset);
-}
-
-// Release module data resource.
-ImageModuleData::~ImageModuleData() {
- if (_data != NULL) {
- FREE_C_HEAP_ARRAY(u1, _data);
- }
-}
-
-// Return the name of the module data resource. Ex. "./lib/modules/file.jimage"
-// yields "file.jdata"
-void ImageModuleData::module_data_name(char* buffer, const char* image_file_name) {
- // Locate the last slash in the file name path.
- const char* slash = strrchr(image_file_name, os::file_separator()[0]);
- // Trim the path to name and extension.
- const char* name = slash != NULL ? slash + 1 : (char *)image_file_name;
- // Locate the extension period.
- const char* dot = strrchr(name, '.');
- guarantee(dot, "missing extension on jimage name");
- // Trim to only base name.
- int length = dot - name;
- strncpy(buffer, name, length);
- buffer[length] = '\0';
- // Append extension.
- strcat(buffer, ".jdata");
-}
-
-// Return the module in which a package resides. Returns NULL if not found.
-const char* ImageModuleData::package_to_module(const char* package_name) {
- // Search the package to module table.
- s4 index = ImageStrings::find(_endian, package_name, _ptm_redirect,
- _header->ptm_count(_endian));
- // If entry is found.
- if (index != ImageStrings::NOT_FOUND) {
- // Retrieve the package to module entry.
- PTMData* data = _ptm_data + index;
- // Verify that it is the correct data.
- if (strcmp(package_name, get_string(data->name_offset(_endian))) != 0) {
- return NULL;
- }
- // Return the module name.
- return get_string(data->module_name_offset(_endian));
- }
- return NULL;
-}
-
-// Returns all the package names in a module. Returns NULL if module not found.
-GrowableArray<const char*>* ImageModuleData::module_to_packages(const char* module_name) {
- // Search the module to package table.
- s4 index = ImageStrings::find(_endian, module_name, _mtp_redirect,
- _header->mtp_count(_endian));
- // If entry is found.
- if (index != ImageStrings::NOT_FOUND) {
- // Retrieve the module to package entry.
- MTPData* data = _mtp_data + index;
- // Verify that it is the correct data.
- if (strcmp(module_name, get_string(data->name_offset(_endian))) != 0) {
- return NULL;
- }
- // Construct an array of all the package entries.
- GrowableArray<const char*>* packages = new GrowableArray<const char*>();
- s4 package_offset = data->package_offset(_endian);
- for (u4 i = 0; i < data->package_count(_endian); i++) {
- u4 package_name_offset = mtp_package(package_offset + i);
- const char* package_name = get_string(package_name_offset);
- packages->append(package_name);
- }
- return packages;
- }
- return NULL;
-}
-
-// Table to manage multiple opens of an image file.
-GrowableArray<ImageFileReader*>* ImageFileReader::_reader_table =
- new(ResourceObj::C_HEAP, mtInternal) GrowableArray<ImageFileReader*>(2, true);
-
-// Open an image file, reuse structure if file already open.
-ImageFileReader* ImageFileReader::open(const char* name, bool big_endian) {
- // Lock out _reader_table.
- MutexLocker ml(ImageFileReaderTable_lock);
- ImageFileReader* reader;
- // Search for an exist image file.
- for (int i = 0; i < _reader_table->length(); i++) {
- // Retrieve table entry.
- reader = _reader_table->at(i);
- // If name matches, then reuse (bump up use count.)
- if (strcmp(reader->name(), name) == 0) {
- reader->inc_use();
- return reader;
- }
- }
- // Need a new image reader.
- reader = new ImageFileReader(name, big_endian);
- bool opened = reader->open();
- // If failed to open.
- if (!opened) {
- delete reader;
- return NULL;
- }
- // Bump use count and add to table.
- reader->inc_use();
- _reader_table->append(reader);
- return reader;
-}
-
-// Close an image file if the file is not in use elsewhere.
-void ImageFileReader::close(ImageFileReader *reader) {
- // Lock out _reader_table.
- MutexLocker ml(ImageFileReaderTable_lock);
- // If last use then remove from table and then close.
- if (reader->dec_use()) {
- _reader_table->remove(reader);
- delete reader;
- }
-}
-
-// Return an id for the specifed ImageFileReader.
-u8 ImageFileReader::readerToID(ImageFileReader *reader) {
- // ID is just the cloaked reader address.
- return (u8)reader;
-}
-
-// Validate the image id.
-bool ImageFileReader::idCheck(u8 id) {
- // Make sure the ID is a managed (_reader_table) reader.
- MutexLocker ml(ImageFileReaderTable_lock);
- return _reader_table->contains((ImageFileReader*)id);
-}
-
-// Return an id for the specifed ImageFileReader.
-ImageFileReader* ImageFileReader::idToReader(u8 id) {
-#ifdef PRODUCT
- // Fast convert.
- return (ImageFileReader*)id;
-#else
- // Do a slow check before fast convert.
- return idCheck(id) ? (ImageFileReader*)id : NULL;
-#endif
-}
-
-// Constructor intializes to a closed state.
-ImageFileReader::ImageFileReader(const char* name, bool big_endian) {
- // Copy the image file name.
- _name = NEW_C_HEAP_ARRAY(char, strlen(name) + 1, mtClass);
- strcpy(_name, name);
- // Initialize for a closed file.
- _fd = -1;
- _endian = Endian::get_handler(big_endian);
- _index_data = NULL;
-}
-
-// Close image and free up data structures.
-ImageFileReader::~ImageFileReader() {
- // Ensure file is closed.
- close();
- // Free up name.
- if (_name != NULL) {
- FREE_C_HEAP_ARRAY(char, _name);
- _name = NULL;
- }
-}
-
-// Open image file for read access.
-bool ImageFileReader::open() {
- // If file exists open for reading.
- struct stat st;
- if (os::stat(_name, &st) != 0 ||
- (st.st_mode & S_IFREG) != S_IFREG ||
- (_fd = os::open(_name, 0, O_RDONLY)) == -1) {
- return false;
- }
- // Retrieve the file size.
- _file_size = (u8)st.st_size;
- // Read image file header and verify it has a valid header.
- size_t header_size = sizeof(ImageHeader);
- if (_file_size < header_size ||
- !read_at((u1*)&_header, header_size, 0) ||
- _header.magic(_endian) != IMAGE_MAGIC ||
- _header.major_version(_endian) != MAJOR_VERSION ||
- _header.minor_version(_endian) != MINOR_VERSION) {
- close();
- return false;
- }
- // Size of image index.
- _index_size = index_size();
- // Make sure file is large enough to contain the index.
- if (_file_size < _index_size) {
- return false;
- }
- // Determine how much of the image is memory mapped.
- off_t map_size = (off_t)(MemoryMapImage ? _file_size : _index_size);
- // Memory map image (minimally the index.)
- _index_data = (u1*)os::map_memory(_fd, _name, 0, NULL, map_size, true, false);
- guarantee(_index_data, "image file not memory mapped");
- // Retrieve length of index perfect hash table.
- u4 length = table_length();
- // Compute offset of the perfect hash table redirect table.
- u4 redirect_table_offset = (u4)header_size;
- // Compute offset of index attribute offsets.
- u4 offsets_table_offset = redirect_table_offset + length * sizeof(s4);
- // Compute offset of index location attribute data.
- u4 location_bytes_offset = offsets_table_offset + length * sizeof(u4);
- // Compute offset of index string table.
- u4 string_bytes_offset = location_bytes_offset + locations_size();
- // Compute address of the perfect hash table redirect table.
- _redirect_table = (s4*)(_index_data + redirect_table_offset);
- // Compute address of index attribute offsets.
- _offsets_table = (u4*)(_index_data + offsets_table_offset);
- // Compute address of index location attribute data.
- _location_bytes = _index_data + location_bytes_offset;
- // Compute address of index string table.
- _string_bytes = _index_data + string_bytes_offset;
- // Successful open.
- return true;
-}
-
-// Close image file.
-void ImageFileReader::close() {
- // Dealllocate the index.
- if (_index_data != NULL) {
- os::unmap_memory((char*)_index_data, _index_size);
- _index_data = NULL;
- }
- // Close file.
- if (_fd != -1) {
- os::close(_fd);
- _fd = -1;
- }
-}
-
-// Read directly from the file.
-bool ImageFileReader::read_at(u1* data, u8 size, u8 offset) const {
- return os::read_at(_fd, data, size, offset) == size;
-}
-
-// Find the location attributes associated with the path. Returns true if
-// the location is found, false otherwise.
-bool ImageFileReader::find_location(const char* path, ImageLocation& location) const {
- // Locate the entry in the index perfect hash table.
- s4 index = ImageStrings::find(_endian, path, _redirect_table, table_length());
- // If is found.
- if (index != ImageStrings::NOT_FOUND) {
- // Get address of first byte of location attribute stream.
- u1* data = get_location_data(index);
- // Expand location attributes.
- location.set_data(data);
- // Make sure result is not a false positive.
- return verify_location(location, path);
- }
- return false;
-}
-
-// Assemble the location path from the string fragments indicated in the location attributes.
-void ImageFileReader::location_path(ImageLocation& location, char* path, size_t max) const {
- // Manage the image string table.
- ImageStrings strings(_string_bytes, _header.strings_size(_endian));
- // Position to first character of the path buffer.
- char* next = path;
- // Temp for string length.
- size_t length;
- // Get module string.
- const char* module = location.get_attribute(ImageLocation::ATTRIBUTE_MODULE, strings);
- // If module string is not empty string.
- if (*module != '\0') {
- // Get length of module name.
- length = strlen(module);
- // Make sure there is no buffer overflow.
- guarantee(next - path + length + 2 < max, "buffer overflow");
- // Append '/module/'.
- *next++ = '/';
- strcpy(next, module); next += length;
- *next++ = '/';
- }
- // Get parent (package) string.
- const char* parent = location.get_attribute(ImageLocation::ATTRIBUTE_PARENT, strings);
- // If parent string is not empty string.
- if (*parent != '\0') {
- // Get length of module string.
- length = strlen(parent);
- // Make sure there is no buffer overflow.
- guarantee(next - path + length + 1 < max, "buffer overflow");
- // Append 'patent/' .
- strcpy(next, parent); next += length;
- *next++ = '/';
- }
- // Get base name string.
- const char* base = location.get_attribute(ImageLocation::ATTRIBUTE_BASE, strings);
- // Get length of base name.
- length = strlen(base);
- // Make sure there is no buffer overflow.
- guarantee(next - path + length < max, "buffer overflow");
- // Append base name.
- strcpy(next, base); next += length;
- // Get extension string.
- const char* extension = location.get_attribute(ImageLocation::ATTRIBUTE_EXTENSION, strings);
- // If extension string is not empty string.
- if (*extension != '\0') {
- // Get length of extension string.
- length = strlen(extension);
- // Make sure there is no buffer overflow.
- guarantee(next - path + length + 1 < max, "buffer overflow");
- // Append '.extension' .
- *next++ = '.';
- strcpy(next, extension); next += length;
- }
- // Make sure there is no buffer overflow.
- guarantee((size_t)(next - path) < max, "buffer overflow");
- // Terminate string.
- *next = '\0';
-}
-
-// Verify that a found location matches the supplied path (without copying.)
-bool ImageFileReader::verify_location(ImageLocation& location, const char* path) const {
- // Manage the image string table.
- ImageStrings strings(_string_bytes, _header.strings_size(_endian));
- // Position to first character of the path string.
- const char* next = path;
- // Get module name string.
- const char* module = location.get_attribute(ImageLocation::ATTRIBUTE_MODULE, strings);
- // If module string is not empty.
- if (*module != '\0') {
- // Compare '/module/' .
- if (*next++ != '/') return false;
- if (!(next = ImageStrings::starts_with(next, module))) return false;
- if (*next++ != '/') return false;
- }
- // Get parent (package) string
- const char* parent = location.get_attribute(ImageLocation::ATTRIBUTE_PARENT, strings);
- // If parent string is not empty string.
- if (*parent != '\0') {
- // Compare 'parent/' .
- if (!(next = ImageStrings::starts_with(next, parent))) return false;
- if (*next++ != '/') return false;
- }
- // Get base name string.
- const char* base = location.get_attribute(ImageLocation::ATTRIBUTE_BASE, strings);
- // Compare with basne name.
- if (!(next = ImageStrings::starts_with(next, base))) return false;
- // Get extension string.
- const char* extension = location.get_attribute(ImageLocation::ATTRIBUTE_EXTENSION, strings);
- // If extension is not empty.
- if (*extension != '\0') {
- // Compare '.extension' .
- if (*next++ != '.') return false;
- if (!(next = ImageStrings::starts_with(next, extension))) return false;
- }
- // True only if complete match and no more characters.
- return *next == '\0';
-}
-
-// Return the resource data for the supplied location.
-void ImageFileReader::get_resource(ImageLocation& location, u1* uncompressed_data) const {
- // Retrieve the byte offset and size of the resource.
- u8 offset = location.get_attribute(ImageLocation::ATTRIBUTE_OFFSET);
- u8 uncompressed_size = location.get_attribute(ImageLocation::ATTRIBUTE_UNCOMPRESSED);
- u8 compressed_size = location.get_attribute(ImageLocation::ATTRIBUTE_COMPRESSED);
- if (compressed_size != 0) {
- ResourceMark rm;
- u1* compressed_data;
- // If not memory mapped read in bytes.
- if (!MemoryMapImage) {
- // Allocate buffer for compression.
- compressed_data = NEW_RESOURCE_ARRAY(u1, compressed_size);
- // Read bytes from offset beyond the image index.
- bool is_read = read_at(compressed_data, compressed_size, _index_size + offset);
- guarantee(is_read, "error reading from image or short read");
- } else {
- compressed_data = get_data_address() + offset;
- }
- // Get image string table.
- const ImageStrings strings = get_strings();
- // Decompress resource.
- ImageDecompressor::decompress_resource(compressed_data, uncompressed_data, uncompressed_size,
- &strings, false);
- } else {
- // Read bytes from offset beyond the image index.
- bool is_read = read_at(uncompressed_data, uncompressed_size, _index_size + offset);
- guarantee(is_read, "error reading from image or short read");
- }
-}