Mercurial > hg > truffle
diff src/share/vm/classfile/classFileStream.hpp @ 0:a61af66fc99e jdk7-b24
Initial load
author | duke |
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date | Sat, 01 Dec 2007 00:00:00 +0000 |
parents | |
children | c18cbe5936b8 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/share/vm/classfile/classFileStream.hpp Sat Dec 01 00:00:00 2007 +0000 @@ -0,0 +1,118 @@ +/* + * Copyright 1997-2005 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. + * + */ + +// Input stream for reading .class file +// +// The entire input stream is present in a buffer allocated by the caller. +// The caller is responsible for deallocating the buffer and for using +// ResourceMarks appropriately when constructing streams. + +class ClassFileStream: public ResourceObj { + private: + u1* _buffer_start; // Buffer bottom + u1* _buffer_end; // Buffer top (one past last element) + u1* _current; // Current buffer position + char* _source; // Source of stream (directory name, ZIP/JAR archive name) + bool _need_verify; // True if verification is on for the class file + + void truncated_file_error(TRAPS); + public: + // Constructor + ClassFileStream(u1* buffer, int length, char* source); + + // Buffer access + u1* buffer() const { return _buffer_start; } + int length() const { return _buffer_end - _buffer_start; } + u1* current() const { return _current; } + void set_current(u1* pos) { _current = pos; } + char* source() const { return _source; } + void set_verify(bool flag) { _need_verify = flag; } + + void check_truncated_file(bool b, TRAPS) { + if (b) { + truncated_file_error(THREAD); + } + } + + void guarantee_more(int size, TRAPS) { + size_t remaining = (size_t)(_buffer_end - _current); + unsigned int usize = (unsigned int)size; + check_truncated_file(usize > remaining, CHECK); + } + + // Read u1 from stream + u1 get_u1(TRAPS); + u1 get_u1_fast() { + return *_current++; + } + + // Read u2 from stream + u2 get_u2(TRAPS); + u2 get_u2_fast() { + u2 res = Bytes::get_Java_u2(_current); + _current += 2; + return res; + } + + // Read u4 from stream + u4 get_u4(TRAPS); + u4 get_u4_fast() { + u4 res = Bytes::get_Java_u4(_current); + _current += 4; + return res; + } + + // Read u8 from stream + u8 get_u8(TRAPS); + u8 get_u8_fast() { + u8 res = Bytes::get_Java_u8(_current); + _current += 8; + return res; + } + + // Get direct pointer into stream at current position. + // Returns NULL if length elements are not remaining. The caller is + // responsible for calling skip below if buffer contents is used. + u1* get_u1_buffer() { + return _current; + } + + u2* get_u2_buffer() { + return (u2*) _current; + } + + // Skip length u1 or u2 elements from stream + void skip_u1(int length, TRAPS); + void skip_u1_fast(int length) { + _current += length; + } + + void skip_u2(int length, TRAPS); + void skip_u2_fast(int length) { + _current += 2 * length; + } + + // Tells whether eos is reached + bool at_eos() const { return _current == _buffer_end; } +};