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Diffstat (limited to 'gfx/graphite2/src/inc/Code.h')
| -rw-r--r-- | gfx/graphite2/src/inc/Code.h | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/gfx/graphite2/src/inc/Code.h b/gfx/graphite2/src/inc/Code.h new file mode 100644 index 000000000..3985ae416 --- /dev/null +++ b/gfx/graphite2/src/inc/Code.h @@ -0,0 +1,171 @@ +/* GRAPHITE2 LICENSING + + Copyright 2010, SIL International + All rights reserved. + + This library is free software; you can redistribute it and/or modify + it under the terms of the GNU Lesser General Public License as published + by the Free Software Foundation; either version 2.1 of License, or + (at your option) any later version. + + This program 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 + Lesser General Public License for more details. + + You should also have received a copy of the GNU Lesser General Public + License along with this library in the file named "LICENSE". + If not, write to the Free Software Foundation, 51 Franklin Street, + Suite 500, Boston, MA 02110-1335, USA or visit their web page on the + internet at http://www.fsf.org/licenses/lgpl.html. + +Alternatively, the contents of this file may be used under the terms of the +Mozilla Public License (http://mozilla.org/MPL) or the GNU General Public +License, as published by the Free Software Foundation, either version 2 +of the License or (at your option) any later version. +*/ +// This class represents loaded graphite stack machine code. It performs +// basic sanity checks, on the incoming code to prevent more obvious problems +// from crashing graphite. +// Author: Tim Eves + +#pragma once + +#include <cassert> +#include <graphite2/Types.h> +#include "inc/Main.h" +#include "inc/Machine.h" + +namespace graphite2 { + +class Silf; +class Face; + +enum passtype { + PASS_TYPE_UNKNOWN = 0, + PASS_TYPE_LINEBREAK, + PASS_TYPE_SUBSTITUTE, + PASS_TYPE_POSITIONING, + PASS_TYPE_JUSTIFICATION +}; + +namespace vm { + +class Machine::Code +{ +public: + enum status_t + { + loaded, + alloc_failed, + invalid_opcode, + unimplemented_opcode_used, + out_of_range_data, + jump_past_end, + arguments_exhausted, + missing_return, + nested_context_item, + underfull_stack + }; + +private: + class decoder; + + instr * _code; + byte * _data; + size_t _data_size, + _instr_count; + byte _max_ref; + mutable status_t _status; + bool _constraint, + _modify, + _delete; + mutable bool _own; + + void release_buffers() throw (); + void failure(const status_t) throw(); + +public: + static size_t estimateCodeDataOut(size_t num_bytecodes, int nRules, int nSlots); + + Code() throw(); + Code(bool is_constraint, const byte * bytecode_begin, const byte * const bytecode_end, + uint8 pre_context, uint16 rule_length, const Silf &, const Face &, + enum passtype pt, byte * * const _out = 0); + Code(const Machine::Code &) throw(); + ~Code() throw(); + + Code & operator=(const Code &rhs) throw(); + operator bool () const throw() { return _code && status() == loaded; } + status_t status() const throw() { return _status; } + bool constraint() const throw() { return _constraint; } + size_t dataSize() const throw() { return _data_size; } + size_t instructionCount() const throw() { return _instr_count; } + bool immutable() const throw() { return !(_delete || _modify); } + bool deletes() const throw() { return _delete; } + size_t maxRef() const throw() { return _max_ref; } + void externalProgramMoved(ptrdiff_t) throw(); + + int32 run(Machine &m, slotref * & map) const; + + CLASS_NEW_DELETE; +}; + +inline +size_t Machine::Code::estimateCodeDataOut(size_t n_bc, int nRules, int nSlots) +{ + // max is: all codes are instructions + 1 for each rule + max tempcopies + // allocate space for separate maximal code and data then merge them later + return (n_bc + nRules + nSlots) * sizeof(instr) + n_bc * sizeof(byte); +} + + +inline Machine::Code::Code() throw() +: _code(0), _data(0), _data_size(0), _instr_count(0), _max_ref(0), + _status(loaded), _constraint(false), _modify(false), _delete(false), + _own(false) +{ +} + +inline Machine::Code::Code(const Machine::Code &obj) throw () + : _code(obj._code), + _data(obj._data), + _data_size(obj._data_size), + _instr_count(obj._instr_count), + _max_ref(obj._max_ref), + _status(obj._status), + _constraint(obj._constraint), + _modify(obj._modify), + _delete(obj._delete), + _own(obj._own) +{ + obj._own = false; +} + +inline Machine::Code & Machine::Code::operator=(const Machine::Code &rhs) throw() { + if (_instr_count > 0) + release_buffers(); + _code = rhs._code; + _data = rhs._data; + _data_size = rhs._data_size; + _instr_count = rhs._instr_count; + _status = rhs._status; + _constraint = rhs._constraint; + _modify = rhs._modify; + _delete = rhs._delete; + _own = rhs._own; + rhs._own = false; + return *this; +} + +inline void Machine::Code::externalProgramMoved(ptrdiff_t dist) throw() +{ + if (_code && !_own) + { + _code += dist / sizeof(instr); + _data += dist; + } +} + +} // namespace vm +} // namespace graphite2 |