src/java.base/share/native/libjimage/imageFile.cpp
changeset 47216 71c04702a3d5
parent 39759 427916042881
child 48565 871b8bb201ea
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.base/share/native/libjimage/imageFile.cpp	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,622 @@
+/*
+ * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *   - Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *
+ *   - Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *
+ *   - Neither the name of Oracle nor the names of its
+ *     contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <assert.h>
+#include <string.h>
+#include <stdlib.h>
+
+#include "endian.hpp"
+#include "imageDecompressor.hpp"
+#include "imageFile.hpp"
+#include "inttypes.hpp"
+#include "jni.h"
+#include "osSupport.hpp"
+
+// Map the full jimage, only with 64 bit addressing.
+bool ImageFileReader::memory_map_image = sizeof(void *) == 8;
+
+#ifdef WIN32
+const char FileSeparator = '\\';
+#else
+const char FileSeparator = '/';
+#endif
+
+// 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.
+// Returns the index where the name should be.
+// 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 || !length) {
+        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 ((data != NULL) && (byte = *data)) {
+        // Extract kind from header byte.
+        u1 kind = attribute_kind(byte);
+        assert(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) :
+        _image_file(image_file),
+        _endian(image_file->endian()) {
+}
+
+// Release module data resource.
+ImageModuleData::~ImageModuleData() {
+}
+
+
+// Return the module in which a package resides.    Returns NULL if not found.
+const char* ImageModuleData::package_to_module(const char* package_name) {
+    // replace all '/' by '.'
+    char* replaced = new char[(int) strlen(package_name) + 1];
+    assert(replaced != NULL && "allocation failed");
+    int i;
+    for (i = 0; package_name[i] != '\0'; i++) {
+      replaced[i] = package_name[i] == '/' ? '.' : package_name[i];
+    }
+    replaced[i] = '\0';
+
+    // build path /packages/<package_name>
+    const char* radical = "/packages/";
+    char* path = new char[(int) strlen(radical) + (int) strlen(package_name) + 1];
+    assert(path != NULL && "allocation failed");
+    strcpy(path, radical);
+    strcat(path, replaced);
+    delete[] replaced;
+
+    // retrieve package location
+    ImageLocation location;
+    bool found = _image_file->find_location(path, location);
+    if (!found) {
+        delete[] path;
+        return NULL;
+    }
+
+    // retrieve offsets to module name
+    int size = (int)location.get_attribute(ImageLocation::ATTRIBUTE_UNCOMPRESSED);
+    u1* content = new u1[size];
+    assert(content != NULL && "allocation failed");
+    _image_file->get_resource(location, content);
+    u1* ptr = content;
+    // sequence of sizeof(8) isEmpty|offset. Use the first module that is not empty.
+    u4 offset = 0;
+    for (i = 0; i < size; i+=8) {
+        u4 isEmpty = _endian->get(*((u4*)ptr));
+        ptr += 4;
+        if (!isEmpty) {
+            offset = _endian->get(*((u4*)ptr));
+            break;
+        }
+        ptr += 4;
+    }
+    delete[] content;
+    return _image_file->get_strings().get(offset);
+}
+
+// Manage a table of open image files.  This table allows multiple access points
+// to share an open image.
+ImageFileReaderTable::ImageFileReaderTable() : _count(0), _max(_growth) {
+    _table = new ImageFileReader*[_max];
+    assert(_table != NULL && "allocation failed");
+}
+
+ImageFileReaderTable::~ImageFileReaderTable() {
+    delete[] _table;
+}
+
+// Add a new image entry to the table.
+void ImageFileReaderTable::add(ImageFileReader* image) {
+    if (_count == _max) {
+        _max += _growth;
+        _table = static_cast<ImageFileReader**>(realloc(_table, _max * sizeof(ImageFileReader*)));
+    }
+    _table[_count++] = image;
+}
+
+// Remove an image entry from the table.
+void ImageFileReaderTable::remove(ImageFileReader* image) {
+    for (u4 i = 0; i < _count; i++) {
+        if (_table[i] == image) {
+            // Swap the last element into the found slot
+            _table[i] = _table[--_count];
+            break;
+        }
+    }
+
+    if (_count != 0 && _count == _max - _growth) {
+        _max -= _growth;
+        _table = static_cast<ImageFileReader**>(realloc(_table, _max * sizeof(ImageFileReader*)));
+    }
+}
+
+// Determine if image entry is in table.
+bool ImageFileReaderTable::contains(ImageFileReader* image) {
+    for (u4 i = 0; i < _count; i++) {
+        if (_table[i] == image) {
+            return true;
+        }
+    }
+    return false;
+}
+
+// Table to manage multiple opens of an image file.
+ImageFileReaderTable ImageFileReader::_reader_table;
+
+SimpleCriticalSection _reader_table_lock;
+
+// Locate an image if file already open.
+ImageFileReader* ImageFileReader::find_image(const char* name) {
+    // Lock out _reader_table.
+    SimpleCriticalSectionLock cs(&_reader_table_lock);
+    // Search for an exist image file.
+    for (u4 i = 0; i < _reader_table.count(); i++) {
+        // Retrieve table entry.
+        ImageFileReader* reader = _reader_table.get(i);
+        // If name matches, then reuse (bump up use count.)
+        assert(reader->name() != NULL && "reader->name must not be null");
+        if (strcmp(reader->name(), name) == 0) {
+            reader->inc_use();
+            return reader;
+        }
+    }
+
+    return NULL;
+}
+
+// Open an image file, reuse structure if file already open.
+ImageFileReader* ImageFileReader::open(const char* name, bool big_endian) {
+    ImageFileReader* reader = find_image(name);
+    if (reader != NULL) {
+        return reader;
+    }
+
+    // Need a new image reader.
+    reader = new ImageFileReader(name, big_endian);
+    if (reader == NULL || !reader->open()) {
+        // Failed to open.
+        delete reader;
+        return NULL;
+    }
+
+    // Lock to update
+    SimpleCriticalSectionLock cs(&_reader_table_lock);
+    // Search for an existing image file.
+    for (u4 i = 0; i < _reader_table.count(); i++) {
+        // Retrieve table entry.
+        ImageFileReader* existing_reader = _reader_table.get(i);
+        // If name matches, then reuse (bump up use count.)
+        assert(reader->name() != NULL && "reader->name still must not be null");
+        if (strcmp(existing_reader->name(), name) == 0) {
+            existing_reader->inc_use();
+            reader->close();
+            delete reader;
+            return existing_reader;
+        }
+    }
+    // Bump use count and add to table.
+    reader->inc_use();
+    _reader_table.add(reader);
+    return reader;
+}
+
+// Close an image file if the file is not in use elsewhere.
+void ImageFileReader::close(ImageFileReader *reader) {
+    // Lock out _reader_table.
+    SimpleCriticalSectionLock cs(&_reader_table_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::reader_to_ID(ImageFileReader *reader) {
+    // ID is just the cloaked reader address.
+    return (u8)reader;
+}
+
+// Validate the image id.
+bool ImageFileReader::id_check(u8 id) {
+    // Make sure the ID is a managed (_reader_table) reader.
+    SimpleCriticalSectionLock cs(&_reader_table_lock);
+    return _reader_table.contains((ImageFileReader*)id);
+}
+
+// Return an id for the specifed ImageFileReader.
+ImageFileReader* ImageFileReader::id_to_reader(u8 id) {
+    assert(id_check(id) && "invalid image id");
+    return (ImageFileReader*)id;
+}
+
+// Constructor intializes to a closed state.
+ImageFileReader::ImageFileReader(const char* name, bool big_endian) {
+    // Copy the image file name.
+     int len = (int) strlen(name) + 1;
+    _name = new char[len];
+    assert(_name != NULL  && "allocation failed");
+    strncpy(_name, name, len);
+    // 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) {
+        delete[] _name;
+        _name = NULL;
+    }
+}
+
+// Open image file for read access.
+bool ImageFileReader::open() {
+    // If file exists open for reading.
+    _fd = osSupport::openReadOnly(_name);
+    if (_fd == -1) {
+        return false;
+    }
+    // Retrieve the file size.
+    _file_size = osSupport::size(_name);
+    // 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;
+    }
+    // Memory map image (minimally the index.)
+    _index_data = (u1*)osSupport::map_memory(_fd, _name, 0, (size_t)map_size());
+    assert(_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 * (u4)sizeof(s4);
+    // Compute offset of index location attribute data.
+    u4 location_bytes_offset = offsets_table_offset + length * (u4)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;
+
+    // Initialize the module data
+    module_data = new ImageModuleData(this);
+    // Successful open (if memory allocation succeeded).
+    return module_data != NULL;
+}
+
+// Close image file.
+void ImageFileReader::close() {
+    // Deallocate the index.
+    if (_index_data) {
+        osSupport::unmap_memory((char*)_index_data, _index_size);
+        _index_data = NULL;
+    }
+    // Close file.
+    if (_fd != -1) {
+        osSupport::close(_fd);
+        _fd = -1;
+    }
+}
+
+// Read directly from the file.
+bool ImageFileReader::read_at(u1* data, u8 size, u8 offset) const {
+    return (u8)osSupport::read(_fd, (char*)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;
+}
+
+// Find the location index and size associated with the path.
+// Returns the location index and size if the location is found, 0 otherwise.
+u4 ImageFileReader::find_location_index(const char* path, u8 *size) const {
+    // Locate the entry in the index perfect hash table.
+    s4 index = ImageStrings::find(_endian, path, _redirect_table, table_length());
+    // If found.
+    if (index != ImageStrings::NOT_FOUND) {
+        // Get address of first byte of location attribute stream.
+        u4 offset = get_location_offset(index);
+        u1* data = get_location_offset_data(offset);
+        // Expand location attributes.
+        ImageLocation location(data);
+        // Make sure result is not a false positive.
+        if (verify_location(location, path)) {
+                *size = (jlong)location.get_attribute(ImageLocation::ATTRIBUTE_UNCOMPRESSED);
+                return offset;
+        }
+    }
+    return 0;            // not found
+}
+
+// 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.
+        assert(next - path + length + 2 < max && "buffer overflow");
+        // Append '/module/'.
+        *next++ = '/';
+        strncpy(next, module, length); 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.
+        assert(next - path + length + 1 < max && "buffer overflow");
+        // Append 'patent/' .
+        strncpy(next, parent, length); 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.
+    assert(next - path + length < max && "buffer overflow");
+    // Append base name.
+    strncpy(next, base, length); 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.
+        assert(next - path + length + 1 < max && "buffer overflow");
+        // Append '.extension' .
+        *next++ = '.';
+        strncpy(next, extension, length); next += length;
+    }
+    // Make sure there is no buffer overflow.
+    assert((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 for the supplied location offset.
+void ImageFileReader::get_resource(u4 offset, u1* uncompressed_data) const {
+        // Get address of first byte of location attribute stream.
+        u1* data = get_location_offset_data(offset);
+        // Expand location attributes.
+        ImageLocation location(data);
+        // Read the data
+        get_resource(location, uncompressed_data);
+}
+
+// Return the resource 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 the resource is compressed.
+    if (compressed_size != 0) {
+        u1* compressed_data;
+        // If not memory mapped read in bytes.
+        if (!memory_map_image) {
+            // Allocate buffer for compression.
+            compressed_data = new u1[(size_t)compressed_size];
+            assert(compressed_data != NULL && "allocation failed");
+            // Read bytes from offset beyond the image index.
+            bool is_read = read_at(compressed_data, compressed_size, _index_size + offset);
+            assert(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, _endian);
+        // If not memory mapped then release temporary buffer.
+        if (!memory_map_image) {
+                delete[] compressed_data;
+        }
+    } else {
+        // Read bytes from offset beyond the image index.
+        bool is_read = read_at(uncompressed_data, uncompressed_size, _index_size + offset);
+        assert(is_read && "error reading from image or short read");
+    }
+}
+
+// Return the ImageModuleData for this image
+ImageModuleData * ImageFileReader::get_image_module_data() {
+        return module_data;
+}