1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/vm/code/compressedStream.hpp Sat Dec 01 00:00:00 2007 +0000
1.3 @@ -0,0 +1,120 @@
1.4 +/*
1.5 + * Copyright 1997-2005 Sun Microsystems, Inc. All Rights Reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation.
1.11 + *
1.12 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.13 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.14 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.15 + * version 2 for more details (a copy is included in the LICENSE file that
1.16 + * accompanied this code).
1.17 + *
1.18 + * You should have received a copy of the GNU General Public License version
1.19 + * 2 along with this work; if not, write to the Free Software Foundation,
1.20 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.21 + *
1.22 + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
1.23 + * CA 95054 USA or visit www.sun.com if you need additional information or
1.24 + * have any questions.
1.25 + *
1.26 + */
1.27 +
1.28 +// Simple interface for filing out and filing in basic types
1.29 +// Used for writing out and reading in debugging information.
1.30 +
1.31 +class CompressedStream : public ResourceObj {
1.32 + friend class VMStructs;
1.33 + protected:
1.34 + u_char* _buffer;
1.35 + int _position;
1.36 +
1.37 + enum {
1.38 + // Constants for UNSIGNED5 coding of Pack200
1.39 + lg_H = 6, H = 1<<lg_H, // number of high codes (64)
1.40 + L = (1<<BitsPerByte)-H, // number of low codes (192)
1.41 + MAX_i = 4 // bytes are numbered in (0..4), max 5 bytes
1.42 + };
1.43 +
1.44 + // these inlines are defined only in compressedStream.cpp
1.45 + static inline juint encode_sign(jint value); // for Pack200 SIGNED5
1.46 + static inline jint decode_sign(juint value); // for Pack200 SIGNED5
1.47 + static inline juint reverse_int(juint bits); // to trim trailing float 0's
1.48 +
1.49 + public:
1.50 + CompressedStream(u_char* buffer, int position = 0) {
1.51 + _buffer = buffer;
1.52 + _position = position;
1.53 + }
1.54 +
1.55 + u_char* buffer() const { return _buffer; }
1.56 +
1.57 + // Positioning
1.58 + int position() const { return _position; }
1.59 + void set_position(int position) { _position = position; }
1.60 +};
1.61 +
1.62 +
1.63 +class CompressedReadStream : public CompressedStream {
1.64 + private:
1.65 + inline u_char read() { return _buffer[_position++]; }
1.66 +
1.67 + jint read_int_mb(jint b0); // UNSIGNED5 coding, 2-5 byte cases
1.68 +
1.69 + public:
1.70 + CompressedReadStream(u_char* buffer, int position = 0)
1.71 + : CompressedStream(buffer, position) {}
1.72 +
1.73 + jboolean read_bool() { return (jboolean) read(); }
1.74 + jbyte read_byte() { return (jbyte ) read(); }
1.75 + jchar read_char() { return (jchar ) read_int(); }
1.76 + jshort read_short() { return (jshort ) read_signed_int(); }
1.77 + jint read_int() { jint b0 = read();
1.78 + if (b0 < L) return b0;
1.79 + else return read_int_mb(b0);
1.80 + }
1.81 + jint read_signed_int();
1.82 + jfloat read_float(); // jfloat_cast(reverse_int(read_int()))
1.83 + jdouble read_double(); // jdouble_cast(2*reverse_int(read_int))
1.84 + jlong read_long(); // jlong_from(2*read_signed_int())
1.85 +};
1.86 +
1.87 +
1.88 +class CompressedWriteStream : public CompressedStream {
1.89 + private:
1.90 + bool full() {
1.91 + return _position >= _size;
1.92 + }
1.93 + void store(u_char b) {
1.94 + _buffer[_position++] = b;
1.95 + }
1.96 + void write(u_char b) {
1.97 + if (full()) grow();
1.98 + store(b);
1.99 + }
1.100 + void grow();
1.101 +
1.102 + void write_int_mb(jint value); // UNSIGNED5 coding, 1-5 byte cases
1.103 +
1.104 + protected:
1.105 + int _size;
1.106 +
1.107 + public:
1.108 + CompressedWriteStream(int initial_size);
1.109 + CompressedWriteStream(u_char* buffer, int initial_size, int position = 0)
1.110 + : CompressedStream(buffer, position) { _size = initial_size; }
1.111 +
1.112 + void write_bool(jboolean value) { write(value); }
1.113 + void write_byte(jbyte value) { write(value); }
1.114 + void write_char(jchar value) { write_int(value); }
1.115 + void write_short(jshort value) { write_signed_int(value); }
1.116 + void write_int(jint value) { if ((juint)value < L && !full())
1.117 + store((u_char)value);
1.118 + else write_int_mb(value); }
1.119 + void write_signed_int(jint value); // write_int(encode_sign(value))
1.120 + void write_float(jfloat value); // write_int(reverse_int(jint_cast(v)))
1.121 + void write_double(jdouble value); // write_int(reverse_int(<low,high>))
1.122 + void write_long(jlong value); // write_signed_int(<low,high>)
1.123 +};
