+/** @file archive.cpp
+ *
+ * Archiving of GiNaC expressions. */
+
+/*
+ * GiNaC Copyright (C) 1999 Johannes Gutenberg University Mainz, Germany
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of 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 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <iostream>
+#include <stdexcept>
+
+#include "archive.h"
+#include "registrar.h"
+#include "ex.h"
+#include "config.h"
+#include "utils.h"
+
+#ifndef NO_GINAC_NAMESPACE
+namespace GiNaC {
+#endif // ndef NO_GINAC_NAMESPACE
+
+
+/** Archive an expression.
+ * @param ex the expression to be archived
+ * @param name name under which the expression is stored */
+void archive::archive_ex(const ex &e, const char *name)
+{
+ // Create root node (which recursively archives the whole expression tree)
+ // and add it to the archive
+ archive_node_id id = add_node(archive_node(*this, e));
+
+ // Add root node ID to list of archived expressions
+ archived_ex ae = archived_ex(atomize(name), id);
+ exprs.push_back(ae);
+}
+
+
+/** Add archive_node to archive if the corresponding expression is
+ * not already archived.
+ * @return ID of archived node */
+archive_node_id archive::add_node(const archive_node &n)
+{
+ // Search for node in nodes vector
+ vector<archive_node>::const_iterator i = nodes.begin(), iend = nodes.end();
+ archive_node_id id = 0;
+ while (i != iend) {
+ if (i->has_same_ex_as(n))
+ return id;
+ i++; id++;
+ }
+
+ // Not found, add archive_node to nodes vector
+ nodes.push_back(n);
+ return id;
+}
+
+
+/** Retrieve archive_node by ID. */
+archive_node &archive::get_node(archive_node_id id)
+{
+ if (id >= nodes.size())
+ throw (std::range_error("archive::get_node(): archive node ID out of range"));
+
+ return nodes[id];
+}
+
+
+/** Retrieve expression from archive by name.
+ * @param sym_lst list of pre-defined symbols */
+ex archive::unarchive_ex(const lst &sym_lst, const char *name) const
+{
+ // Find root node
+ string name_string = name;
+ archive_atom id = atomize(name_string);
+ vector<archived_ex>::const_iterator i = exprs.begin(), iend = exprs.end();
+ while (i != iend) {
+ if (i->name == id)
+ goto found;
+ i++;
+ }
+ throw (std::logic_error("expression with name '" + name_string + "' not found in archive"));
+
+found:
+ // Recursively unarchive all nodes, starting at the root node
+ return nodes[i->root].unarchive(sym_lst);
+}
+
+/** Retrieve expression from archive by index.
+ * @param sym_lst list of pre-defined symbols */
+ex archive::unarchive_ex(const lst &sym_lst, unsigned int index) const
+{
+ if (index >= exprs.size())
+ throw (std::range_error("index of archived expression out of range"));
+
+ // Recursively unarchive all nodes, starting at the root node
+ return nodes[exprs[index].root].unarchive(sym_lst);
+}
+
+/** Retrieve expression and its name from archive by index.
+ * @param sym_lst list of pre-defined symbols */
+ex archive::unarchive_ex(const lst &sym_lst, string &name, unsigned int index) const
+{
+ if (index >= exprs.size())
+ throw (std::range_error("index of archived expression out of range"));
+
+ // Return expression name
+ name = unatomize(exprs[index].name);
+
+ // Recursively unarchive all nodes, starting at the root node
+ return nodes[exprs[index].root].unarchive(sym_lst);
+}
+
+
+/** Return number of archived expressions. */
+unsigned int archive::num_expressions(void) const
+{
+ return exprs.size();
+}
+
+
+/*
+ * Archive file format
+ *
+ * - 4 bytes signature 'GARC'
+ * - unsigned version number
+ * - unsigned number of atoms
+ * - atom strings (each zero-terminated)
+ * - unsigned number of expressions
+ * - unsigned name atom
+ * - unsigned root node ID
+ * - unsigned number of nodes
+ * - unsigned number of properties
+ * - unsigned type (PTYPE_*)
+ * - unsigned name atom
+ * - unsigned property value
+ *
+ * Unsigned quantities are stored in a compressed format:
+ * - numbers in the range 0x00..0x7f are stored verbatim (1 byte)
+ * - numbers larger than 0x7f are stored in 7-bit packets (1 byte per
+ * packet), starting with the LSBs; all bytes except the last one have
+ * their upper bit set
+ *
+ * Examples:
+ * 0x00 = 0x00
+ * .. ..
+ * 0x7f = 0x7f
+ * 0x80 0x01 = 0x80
+ * .. .. ..
+ * 0xff 0x01 = 0xff
+ * 0x80 0x02 = 0x100
+ * .. .. ..
+ * 0xff 0x02 = 0x17f
+ * 0x80 0x03 = 0x180
+ * .. .. ..
+ * 0xff 0x7f = 0x3fff
+ * 0x80 0x80 0x01 = 0x4000
+ * .. .. .. ..
+ */
+
+/** Write unsigned integer quantity to stream. */
+static void write_unsigned(ostream &os, unsigned int val)
+{
+ while (val > 0x80) {
+ os.put((val & 0x7f) | 0x80);
+ val >>= 7;
+ }
+ os.put(val);
+}
+
+/** Read unsigned integer quantity from stream. */
+static unsigned int read_unsigned(istream &is)
+{
+ unsigned char b;
+ unsigned int ret = 0;
+ unsigned int shift = 0;
+ do {
+ is.get(b);
+ ret |= (b & 0x7f) << shift;
+ shift += 7;
+ } while (b & 0x80);
+ return ret;
+}
+
+/** Write archive_node to binary data stream. */
+ostream &operator<<(ostream &os, const archive_node &n)
+{
+ // Write properties
+ unsigned int num_props = n.props.size();
+ write_unsigned(os, num_props);
+ for (unsigned int i=0; i<num_props; i++) {
+ write_unsigned(os, n.props[i].type);
+ write_unsigned(os, n.props[i].name);
+ write_unsigned(os, n.props[i].value);
+ }
+}
+
+/** Write archive to binary data stream. */
+ostream &operator<<(ostream &os, const archive &ar)
+{
+ // Write header
+ os.put('G'); // Signature
+ os.put('A');
+ os.put('R');
+ os.put('C');
+ write_unsigned(os, ARCHIVE_VERSION);
+
+ // Write atoms
+ unsigned int num_atoms = ar.atoms.size();
+ write_unsigned(os, num_atoms);
+ for (unsigned int i=0; i<num_atoms; i++)
+ os << ar.atoms[i] << ends;
+
+ // Write expressions
+ unsigned int num_exprs = ar.exprs.size();
+ write_unsigned(os, num_exprs);
+ for (unsigned int i=0; i<num_exprs; i++) {
+ write_unsigned(os, ar.exprs[i].name);
+ write_unsigned(os, ar.exprs[i].root);
+ }
+
+ // Write nodes
+ unsigned int num_nodes = ar.nodes.size();
+ write_unsigned(os, num_nodes);
+ for (unsigned int i=0; i<num_nodes; i++)
+ os << ar.nodes[i];
+}
+
+/** Read archive_node from binary data stream. */
+istream &operator>>(istream &is, archive_node &n)
+{
+ // Read properties
+ unsigned int num_props = read_unsigned(is);
+ n.props.resize(num_props);
+ for (unsigned int i=0; i<num_props; i++) {
+ n.props[i].type = (archive_node::property_type)read_unsigned(is);
+ n.props[i].name = read_unsigned(is);
+ n.props[i].value = read_unsigned(is);
+ }
+}
+
+/** Read archive from binary data stream. */
+istream &operator>>(istream &is, archive &ar)
+{
+ // Read header
+ char c1, c2, c3, c4;
+ is.get(c1); is.get(c2); is.get(c3); is.get(c4);
+ if (c1 != 'G' || c2 != 'A' || c3 != 'R' || c4 != 'C')
+ throw (std::runtime_error("not a GiNaC archive (signature not found)"));
+ unsigned int version = read_unsigned(is);
+ if (version > ARCHIVE_VERSION || version < ARCHIVE_VERSION - ARCHIVE_AGE)
+ throw (std::runtime_error("archive version " + ToString(version) + " cannot be read by this GiNaC library (which supports versions " + ToString(ARCHIVE_VERSION-ARCHIVE_AGE) + " thru " + ToString(ARCHIVE_VERSION)));
+
+ // Read atoms
+ unsigned int num_atoms = read_unsigned(is);
+ ar.atoms.resize(num_atoms);
+ for (unsigned int i=0; i<num_atoms; i++)
+ getline(is, ar.atoms[i], '\0');
+
+ // Read expressions
+ unsigned int num_exprs = read_unsigned(is);
+ ar.exprs.resize(num_exprs);
+ for (unsigned int i=0; i<num_exprs; i++) {
+ archive_atom name = read_unsigned(is);
+ archive_node_id root = read_unsigned(is);
+ ar.exprs[i] = archive::archived_ex(name, root);
+ }
+
+ // Read nodes
+ unsigned int num_nodes = read_unsigned(is);
+ ar.nodes.resize(num_nodes, ar);
+ for (unsigned int i=0; i<num_nodes; i++)
+ is >> ar.nodes[i];
+}
+
+
+/** Atomize a string (i.e. convert it into an ID number that uniquely
+ * represents the string). */
+archive_atom archive::atomize(const string &s) const
+{
+ // Search for string in atoms vector
+ vector<string>::const_iterator i = atoms.begin(), iend = atoms.end();
+ archive_atom id = 0;
+ while (i != iend) {
+ if (*i == s)
+ return id;
+ i++; id++;
+ }
+
+ // Not found, add to atoms vector
+ atoms.push_back(s);
+ return id;
+}
+
+/** Unatomize a string (i.e. convert the ID number back to the string). */
+const string &archive::unatomize(archive_atom id) const
+{
+ if (id >= atoms.size())
+ throw (std::range_error("archive::unatomizee(): atom ID out of range"));
+
+ return atoms[id];
+}
+
+
+/** Copy constructor of archive_node. */
+archive_node::archive_node(const archive_node &other)
+ : a(other.a), props(other.props), has_expression(other.has_expression), e(other.e)
+{
+}
+
+
+/** Assignment operator of archive_node. */
+const archive_node &archive_node::operator=(const archive_node &other)
+{
+ if (this != &other) {
+ a = other.a;
+ props = other.props;
+ has_expression = other.has_expression;
+ e = other.e;
+ }
+ return *this;
+}
+
+
+/** Recursively construct archive node from expression. */
+archive_node::archive_node(archive &ar, const ex &expr)
+ : a(ar), has_expression(true), e(expr)
+{
+ expr.bp->archive(*this);
+}
+
+
+/** Check if the archive_node stores the same expression as another
+ * archive_node.
+ * @return "true" if expressions are the same */
+bool archive_node::has_same_ex_as(const archive_node &other) const
+{
+ if (!has_expression || !other.has_expression)
+ return false;
+ return e.bp == other.e.bp;
+}
+
+
+/** Add property of type "bool" to node. */
+void archive_node::add_bool(const string &name, bool value)
+{
+ props.push_back(property(a.atomize(name), PTYPE_BOOL, value));
+}
+
+/** Add property of type "unsigned int" to node. */
+void archive_node::add_unsigned(const string &name, unsigned int value)
+{
+ props.push_back(property(a.atomize(name), PTYPE_UNSIGNED, value));
+}
+
+/** Add property of type "string" to node. */
+void archive_node::add_string(const string &name, const string &value)
+{
+ props.push_back(property(a.atomize(name), PTYPE_STRING, a.atomize(value)));
+}
+
+/** Add property of type "ex" to node. */
+void archive_node::add_ex(const string &name, const ex &value)
+{
+ // Recursively create an archive_node and add its ID to the properties of this node
+ archive_node_id id = a.add_node(archive_node(a, value));
+ props.push_back(property(a.atomize(name), PTYPE_NODE, id));
+}
+
+
+/** Retrieve property of type "bool" from node.
+ * @return "true" if property was found, "false" otherwise */
+bool archive_node::find_bool(const string &name, bool &ret) const
+{
+ archive_atom name_atom = a.atomize(name);
+ vector<property>::const_iterator i = props.begin(), iend = props.end();
+ while (i != iend) {
+ if (i->type == PTYPE_BOOL && i->name == name_atom) {
+ ret = i->value;
+ return true;
+ }
+ i++;
+ }
+ return false;
+}
+
+/** Retrieve property of type "unsigned" from node.
+ * @return "true" if property was found, "false" otherwise */
+bool archive_node::find_unsigned(const string &name, unsigned int &ret) const
+{
+ archive_atom name_atom = a.atomize(name);
+ vector<property>::const_iterator i = props.begin(), iend = props.end();
+ while (i != iend) {
+ if (i->type == PTYPE_UNSIGNED && i->name == name_atom) {
+ ret = i->value;
+ return true;
+ }
+ i++;
+ }
+ return false;
+}
+
+/** Retrieve property of type "string" from node.
+ * @return "true" if property was found, "false" otherwise */
+bool archive_node::find_string(const string &name, string &ret) const
+{
+ archive_atom name_atom = a.atomize(name);
+ vector<property>::const_iterator i = props.begin(), iend = props.end();
+ while (i != iend) {
+ if (i->type == PTYPE_STRING && i->name == name_atom) {
+ ret = a.unatomize(i->value);
+ return true;
+ }
+ i++;
+ }
+ return false;
+}
+
+/** Retrieve property of type "ex" from node.
+ * @return "true" if property was found, "false" otherwise */
+bool archive_node::find_ex(const string &name, ex &ret, const lst &sym_lst, unsigned int index) const
+{
+ archive_atom name_atom = a.atomize(name);
+ vector<property>::const_iterator i = props.begin(), iend = props.end();
+ unsigned int found_index = 0;
+ while (i != iend) {
+ if (i->type == PTYPE_NODE && i->name == name_atom) {
+ if (found_index == index)
+ goto found;
+ found_index++;
+ }
+ i++;
+ }
+ return false;
+
+found:
+ ret = a.get_node(i->value).unarchive(sym_lst);
+ return true;
+}
+
+
+/** Convert archive node to GiNaC expression. */
+ex archive_node::unarchive(const lst &sym_lst) const
+{
+ // Already unarchived? Then return cached unarchived expression.
+ if (has_expression)
+ return e;
+
+ // Find instantiation function for class specified in node
+ string class_name;
+ if (!find_string("class", class_name))
+ throw (std::runtime_error("archive node contains no class name"));
+ unarch_func f = find_unarch_func(class_name);
+
+ // Call instantiation function
+ e = f(*this, sym_lst);
+ has_expression = true;
+ return e;
+}
+
+
+/** Assignment operator of property. */
+const archive_node::property &archive_node::property::operator=(const property &other)
+{
+ if (this != &other) {
+ type = other.type;
+ name = other.name;
+ value = other.value;
+ }
+ return *this;
+}
+
+
+/** Clear all archived expressions. */
+void archive::clear(void)
+{
+ atoms.clear();
+ exprs.clear();
+ nodes.clear();
+}
+
+
+/** Delete cached unarchived expressions in all archive_nodes (mainly for debugging). */
+void archive::forget(void)
+{
+ vector<archive_node>::iterator i = nodes.begin(), iend = nodes.end();
+ while (i != iend) {
+ i->forget();
+ i++;
+ }
+}
+
+/** Delete cached unarchived expressions from node (for debugging). */
+void archive_node::forget(void)
+{
+ has_expression = false;
+ e = 0;
+}
+
+
+/** Dump archive to stream (for debugging). */
+void archive::dump(ostream &os) const
+{
+ // Dump atoms
+ os << "Atoms:\n";
+ {
+ vector<string>::const_iterator i = atoms.begin(), iend = atoms.end();
+ archive_atom id = 0;
+ while (i != iend) {
+ os << " " << id << " " << *i << endl;
+ i++; id++;
+ }
+ }
+ os << endl;
+
+ // Dump expressions
+ os << "Expressions:\n";
+ {
+ vector<archived_ex>::const_iterator i = exprs.begin(), iend = exprs.end();
+ unsigned int index = 0;
+ while (i != iend) {
+ os << " " << index << " \"" << unatomize(i->name) << "\" root node " << i->root << endl;
+ i++; index++;
+ }
+ }
+ os << endl;
+
+ // Dump nodes
+ os << "Nodes:\n";
+ {
+ vector<archive_node>::const_iterator i = nodes.begin(), iend = nodes.end();
+ archive_node_id id = 0;
+ while (i != iend) {
+ os << " " << id << " ";
+ i->dump(os);
+ i++; id++;
+ }
+ }
+}
+
+/** Dump archive_node to stream (for debugging). */
+void archive_node::dump(ostream &os) const
+{
+ // Dump cached unarchived expression
+ if (has_expression)
+ os << "(basic * " << e.bp << " = " << e << ")\n";
+ else
+ os << "(no expression)\n";
+
+ // Dump properties
+ vector<property>::const_iterator i = props.begin(), iend = props.end();
+ while (i != iend) {
+ os << " ";
+ switch (i->type) {
+ case PTYPE_BOOL: os << "bool"; break;
+ case PTYPE_UNSIGNED: os << "unsigned"; break;
+ case PTYPE_STRING: os << "string"; break;
+ case PTYPE_NODE: os << "node"; break;
+ default: os << "<unknown>"; break;
+ }
+ os << " \"" << a.unatomize(i->name) << "\" " << i->value << endl;
+ i++;
+ }
+}
+
+
+#ifndef NO_GINAC_NAMESPACE
+} // namespace GiNaC
+#endif // ndef NO_GINAC_NAMESPACE