3 * Archiving of GiNaC expressions. */
6 * GiNaC Copyright (C) 1999-2020 Johannes Gutenberg University Mainz, Germany
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 #ifndef GINAC_ARCHIVE_H
24 #define GINAC_ARCHIVE_H
38 /** Numerical ID value to refer to an archive_node. */
39 typedef unsigned archive_node_id;
41 /** Numerical ID value to refer to a string. */
42 typedef unsigned archive_atom;
45 /** This class stores all properties needed to record/retrieve the state
46 * of one object of class basic (or a derived class). Each property is
47 * addressed by its name and data type. */
50 friend std::ostream &operator<<(std::ostream &os, const archive_node &ar);
51 friend std::istream &operator>>(std::istream &is, archive_node &ar);
54 /** Property data types */
62 /** Information about a stored property. A vector of these structures
63 * is returned by get_properties().
64 * @see get_properties */
65 struct property_info {
67 property_info(property_type t, const std::string &n, unsigned c = 1) : type(t), name(n), count(c) {}
69 property_type type; /**< Data type of property. */
70 std::string name; /**< Name of property. */
71 unsigned count; /**< Number of occurrences. */
73 typedef std::vector<property_info> propinfovector;
75 /** Archived property (data type, name and associated data) */
78 property(archive_atom n, property_type t, unsigned v) : type(t), name(n), value(v) {}
80 property_type type; /**< Data type of property. */
81 archive_atom name; /**< Name of property. */
82 unsigned value; /**< Stored value. */
84 typedef std::vector<property>::const_iterator archive_node_cit;
85 struct archive_node_cit_range {
86 archive_node_cit begin, end;
89 archive_node(archive &ar) : a(ar), has_expression(false) {}
90 archive_node(archive &ar, const ex &expr);
92 const archive_node &operator=(const archive_node &other);
94 /** Add property of type "bool" to node. */
95 void add_bool(const std::string &name, bool value);
97 /** Add property of type "unsigned int" to node. */
98 void add_unsigned(const std::string &name, unsigned value);
100 /** Add property of type "string" to node. */
101 void add_string(const std::string &name, const std::string &value);
103 /** Add property of type "ex" to node. */
104 void add_ex(const std::string &name, const ex &value);
106 /** Retrieve property of type "bool" from node.
107 * @return "true" if property was found, "false" otherwise */
108 bool find_bool(const std::string &name, bool &ret, unsigned index = 0) const;
110 /** Retrieve property of type "unsigned" from node.
111 * @return "true" if property was found, "false" otherwise */
112 bool find_unsigned(const std::string &name, unsigned &ret, unsigned index = 0) const;
114 /** Retrieve property of type "string" from node.
115 * @return "true" if property was found, "false" otherwise */
116 bool find_string(const std::string &name, std::string &ret, unsigned index = 0) const;
118 /** Find the location in the vector of properties of the first/last
119 * property with a given name. */
120 archive_node_cit find_first(const std::string &name) const;
121 archive_node_cit find_last(const std::string &name) const;
123 /** Find a range of locations in the vector of properties. The result
124 * begins at the first property with name1 and ends one past the last
125 * property with name2. */
126 archive_node_cit_range find_property_range(const std::string &name1, const std::string &name2) const;
128 /** Retrieve property of type "ex" from node.
129 * @return "true" if property was found, "false" otherwise */
130 bool find_ex(const std::string &name, ex &ret, lst &sym_lst, unsigned index = 0) const;
132 /** Retrieve property of type "ex" from the node if it is known
133 * that this node in fact contains such a property at the given
134 * location. This is much more efficient than the preceding function. */
135 void find_ex_by_loc(archive_node_cit loc, ex &ret, lst &sym_lst) const;
137 /** Retrieve property of type "ex" from node, returning the node of
138 * the sub-expression. */
139 const archive_node &find_ex_node(const std::string &name, unsigned index = 0) const;
141 /** Return vector of properties stored in node. */
142 void get_properties(propinfovector &v) const;
144 ex unarchive(lst &sym_lst) const;
145 bool has_same_ex_as(const archive_node &other) const;
146 bool has_ex() const {return has_expression;}
147 ex get_ex() const {return e;}
150 void printraw(std::ostream &os) const;
153 /** Reference to the archive to which this node belongs. */
156 /** Vector of stored properties. */
157 std::vector<property> props;
159 /** Flag indicating whether a cached unarchived representation of this node exists. */
160 mutable bool has_expression;
162 /** The cached unarchived representation of this node (if any). */
166 typedef basic* (*synthesize_func)();
167 typedef std::map<std::string, synthesize_func> unarchive_map_t;
169 class unarchive_table_t
172 static unarchive_map_t* unarch_map;
175 ~unarchive_table_t();
176 synthesize_func find(const std::string& classname) const;
177 void insert(const std::string& classname, synthesize_func f);
179 static unarchive_table_t unarch_table_instance;
181 /** Helper macros to register a class with (un)archiving (a.k.a.
182 * (de)serialization).
186 * GINAC_DECLARE_UNARCHIVER(myclass);
188 * into the header file (in the global or namespace scope), and
190 * GINAC_BIND_UNARCHIVER(myclass);
192 * into the source file.
194 * Effect: the `myclass' (being a class derived directly or indirectly
195 * from GiNaC::basic) can be archived and unarchived.
197 * Note: you need to use GINAC_{DECLARE,BIND}_UNARCHIVER incantations
198 * in order to make your class (un)archivable _even if your class does
199 * not overload `read_archive' method_. Sorry for inconvenience.
203 * The `basic' class has a `read_archive' virtual method which reads an
204 * expression from archive. Derived classes can overload that method.
205 * There's a small problem, though. On unarchiving all we have is a set
206 * of named byte streams. In C++ the class name (as written in the source
207 * code) has nothing to do with its actual type. Thus, we need establish
208 * a correspondence ourselves. To do so we maintain a `class_name' =>
209 * `function_pointer' table (see the unarchive_table_t class above).
210 * Every function in this table is supposed to create a new object of
211 * the `class_name' type. The `archive_node' class uses that table to
212 * construct an object of correct type. Next it invokes read_archive
213 * virtual method of newly created object, which does the actual job.
215 * Note: this approach is very simple-minded (it does not handle classes
216 * with same names from different namespaces, multiple inheritance, etc),
217 * but it happens to work surprisingly well.
219 #define GINAC_DECLARE_UNARCHIVER(classname) \
220 class classname ## _unarchiver \
222 static int usecount; \
224 static GiNaC::basic* create(); \
225 classname ## _unarchiver(); \
226 ~ classname ## _unarchiver(); \
228 static classname ## _unarchiver classname ## _unarchiver_instance
230 #define GINAC_BIND_UNARCHIVER(classname) \
231 classname ## _unarchiver::classname ## _unarchiver() \
233 static GiNaC::unarchive_table_t table; \
234 if (usecount++ == 0) { \
235 table.insert(std::string(#classname), \
236 &(classname ## _unarchiver::create)); \
239 GiNaC::basic* classname ## _unarchiver::create() \
241 return new classname(); \
243 classname ## _unarchiver::~ classname ## _unarchiver() { } \
244 int classname ## _unarchiver::usecount = 0
247 /** This class holds archived versions of GiNaC expressions (class ex).
248 * An archive can be constructed from an expression and then written to
249 * a stream; or it can be read from a stream and then unarchived, yielding
250 * back the expression. Archives can hold multiple expressions which can
251 * be referred to by name or index number. The main component of the
252 * archive class is a vector of archive_nodes which each store one object
253 * of class basic (or a derived class). */
256 friend std::ostream &operator<<(std::ostream &os, const archive &ar);
257 friend std::istream &operator>>(std::istream &is, archive &ar);
263 /** Construct archive from expression using the default name "ex". */
264 archive(const ex &e) {archive_ex(e, "ex");}
266 /** Construct archive from expression using the specified name. */
267 archive(const ex &e, const char *n) {archive_ex(e, n);}
269 /** Archive an expression.
270 * @param e the expression to be archived
271 * @param name name under which the expression is stored */
272 void archive_ex(const ex &e, const char *name);
274 /** Retrieve expression from archive by name.
275 * @param sym_lst list of pre-defined symbols
276 * @param name name of expression */
277 ex unarchive_ex(const lst &sym_lst, const char *name) const;
279 /** Retrieve expression from archive by index.
280 * @param sym_lst list of pre-defined symbols
281 * @param index index of expression
282 * @see count_expressions */
283 ex unarchive_ex(const lst &sym_lst, unsigned index = 0) const;
285 /** Retrieve expression and its name from archive by index.
286 * @param sym_lst list of pre-defined symbols
287 * @param name receives the name of the expression
288 * @param index index of expression
289 * @see count_expressions */
290 ex unarchive_ex(const lst &sym_lst, std::string &name, unsigned index = 0) const;
292 /** Return number of archived expressions. */
293 unsigned num_expressions() const;
295 /** Return reference to top node of an expression specified by index. */
296 const archive_node &get_top_node(unsigned index = 0) const;
298 /** Clear all archived expressions. */
301 archive_node_id add_node(const archive_node &n);
302 archive_node &get_node(archive_node_id id);
305 void printraw(std::ostream &os) const;
308 /** Vector of archived nodes. */
309 std::vector<archive_node> nodes;
311 /** Archived expression descriptor. */
314 archived_ex(archive_atom n, archive_node_id node) : name(n), root(node) {}
316 archive_atom name; /**< Name of expression. */
317 archive_node_id root; /**< ID of root node. */
320 /** Vector of archived expression descriptors. */
321 std::vector<archived_ex> exprs;
324 archive_atom atomize(const std::string &s) const;
325 const std::string &unatomize(archive_atom id) const;
328 /** Vector of atomized strings (using a vector allows faster unarchiving). */
329 mutable std::vector<std::string> atoms;
330 /** The map of from strings to indices of the atoms vectors allows for
333 typedef std::map<std::string, archive_atom>::const_iterator inv_at_cit;
334 mutable std::map<std::string, archive_atom> inverse_atoms;
336 /** Map of stored expressions to nodes for faster archiving */
337 mutable std::map<ex, archive_node_id, ex_is_less> exprtable;
341 std::ostream &operator<<(std::ostream &os, const archive &ar);
342 std::istream &operator>>(std::istream &is, archive &ar);
346 #endif // ndef GINAC_ARCHIVE_H