2 * This file is part of GNUnet.
3 * Copyright (C) 2013 Christian Grothoff (and other contributing authors)
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6 * it under the terms of the GNU General Public License as published
7 * by the Free Software Foundation; either version 3, or (at your
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11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with GNUnet; see the file COPYING. If not, write to the
17 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 * Boston, MA 02111-1307, USA.
22 * @file include/gnunet_env_lib.h
23 * @brief Library providing operations for the @e environment of
24 * PSYC and Social messages, and for (de)serializing variable values.
25 * @author Gabor X Toth
29 #ifndef GNUNET_ENV_LIB_H
30 #define GNUNET_ENV_LIB_H
35 #if 0 /* keep Emacsens' auto-indent happy */
42 * Possible operations on PSYC state (persistent) and transient variables (per message).
44 enum GNUNET_ENV_Operator
47 * Set value of a transient variable.
49 GNUNET_ENV_OP_SET = ':',
52 * Assign value for a persistent state variable.
54 * If an assigned value is NULL, the variable is deleted.
56 GNUNET_ENV_OP_ASSIGN = '=',
59 * Augment state variable.
61 * Used for appending strings, adding numbers, and adding new items to a list or dictionary.
63 GNUNET_ENV_OP_AUGMENT = '+',
66 * Diminish state variable.
68 * Used for subtracting numbers, and removing items from a list or dictionary.
70 GNUNET_ENV_OP_DIMINISH = '-',
73 * Update state variable.
75 * Used for modifying a single item of a list or dictionary.
77 GNUNET_ENV_OP_UPDATE = '@',
82 * PSYC variable types.
86 GNUNET_ENV_TYPE_DATA = 0,
87 GNUNET_ENV_TYPE_NUMBER,
94 * PSYC state modifier.
96 struct GNUNET_ENV_Modifier
101 enum GNUNET_ENV_Operator oper;
121 struct GNUNET_ENV_Modifier *next;
126 struct GNUNET_ENV_Modifier *prev;
131 * Environment for a message.
133 * Contains modifiers.
135 struct GNUNET_ENV_Environment;
139 * Create an environment.
141 * @return A newly allocated environment.
143 struct GNUNET_ENV_Environment *
144 GNUNET_ENV_environment_create ();
148 * Add a modifier to the environment.
150 * @param env The environment.
151 * @param oper Operation to perform.
152 * @param name Name of the variable.
153 * @param value Value of the variable.
154 * @param value_size Size of @a value.
157 GNUNET_ENV_environment_add (struct GNUNET_ENV_Environment *env,
158 enum GNUNET_ENV_Operator oper, const char *name,
159 const void *value, size_t value_size);
163 * Get the first modifier of the environment.
165 struct GNUNET_ENV_Modifier *
166 GNUNET_ENV_environment_head (const struct GNUNET_ENV_Environment *env);
171 * Get the last modifier of the environment.
173 struct GNUNET_ENV_Modifier *
174 GNUNET_ENV_environment_tail (const struct GNUNET_ENV_Environment *env);
178 * Remove a modifier from the environment.
181 GNUNET_ENV_environment_remove (struct GNUNET_ENV_Environment *env,
182 struct GNUNET_ENV_Modifier *mod);
186 * Remove a modifier at the beginning of the environment.
189 GNUNET_ENV_environment_shift (struct GNUNET_ENV_Environment *env,
190 enum GNUNET_ENV_Operator *oper, const char **name,
191 const void **value, size_t *value_size);
195 * Iterator for modifiers in the environment.
197 * @param cls Closure.
198 * @param mod Modifier.
200 * @return #GNUNET_YES to continue iterating,
201 * #GNUNET_NO to stop.
204 (*GNUNET_ENV_Iterator) (void *cls, enum GNUNET_ENV_Operator oper,
205 const char *name, const char *value,
206 uint32_t value_size);
210 * Iterate through all modifiers in the environment.
212 * @param env The environment.
213 * @param it Iterator.
214 * @param it_cls Closure for iterator.
217 GNUNET_ENV_environment_iterate (const struct GNUNET_ENV_Environment *env,
218 GNUNET_ENV_Iterator it, void *it_cls);
222 * Get the number of modifiers in the environment.
224 * @param env The environment.
226 * @return Number of modifiers.
229 GNUNET_ENV_environment_get_count (const struct GNUNET_ENV_Environment *env);
233 * Destroy an environment.
235 * @param env The environment to destroy.
238 GNUNET_ENV_environment_destroy (struct GNUNET_ENV_Environment *env);
242 * Get the type of variable.
244 * @param name Name of the variable.
246 * @return Variable type.
249 GNUNET_ENV_var_get_type (char *name);
253 * Perform an operation on a variable.
255 * @param name Name of variable.
256 * @param current_value Current value of variable.
257 * @param current_value_size Size of @a current_value.
258 * @param oper Operator.
259 * @param args Arguments for the operation.
260 * @param args_size Size of @a args.
261 * @param return_value Return value.
262 * @param return_value_size Size of @a return_value.
264 * @return #GNUNET_OK on success, else #GNUNET_SYSERR
267 GNUNET_ENV_operation (char *name, void *current_value, size_t current_value_size,
268 enum GNUNET_ENV_Operator oper, void *args, size_t args_size,
269 void **return_value, size_t *return_value_size);
273 * Get the variable's value as an integer.
275 * @param size Size of value.
276 * @param value Raw value of variable.
277 * @param[out] number Value converted to a 64-bit integer.
279 * @return #GNUNET_OK on success, #GNUNET_SYSERR if an error occurred (e.g. the value is invalid).
282 GNUNET_ENV_value_to_number (size_t size, const void *value, int64_t *number);
286 * Get the variable's value as a dictionary.
288 * @param size Size of value.
289 * @param value Raw value of variable.
290 * @param[out] dict A newly created hashmap holding the elements of the dictionary.
292 * @return #GNUNET_OK on success, #GNUNET_SYSERR if an error occurred (e.g. the value is invalid).
295 GNUNET_ENV_value_to_dict (size_t size, const void *value, struct GNUNET_CONTAINER_MultiHashMap **dict);
299 * Create a PSYC variable value from an integer.
301 * @param number The number to convert.
302 * @param[out] value_size Size of returned value.
304 * @return A newly allocated value or NULL on error.
307 GNUNET_ENV_value_from_number (int64_t number, size_t *value_size);
311 * Create a PSYC variable value from a dictionary.
313 * @param dict The dict to convert.
314 * @param[out] value_size Size of returned value.
316 * @return A newly allocated value or NULL on error.
319 GNUNET_ENV_value_from_dict (struct GNUNET_CONTAINER_MultiHashMap *dict, size_t *value_size);
322 #if 0 /* keep Emacsens' auto-indent happy */
329 /* ifndef GNUNET_ENV_LIB_H */
331 /* end of gnunet_env_lib.h */