1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231
|
/* conditions.c
* Implementation for condition handler.
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "config.h"
#include <string.h>
#include <stdlib.h>
#include <stdarg.h>
#include "conditions.h"
/* container for condition classes */
static GHashTable *classes = NULL;
/* condition data structure declaration */
struct condition{
char *class_id;
void *user_data;
_cnd_eval eval_func;
_cnd_reset reset_func;
};
/* structure used to store class functions in GHashTable */
typedef struct _cnd_class{
_cnd_constr constr_func;
_cnd_destr destr_func;
_cnd_eval eval_func;
_cnd_reset reset_func;
} _cnd_class;
/* helper function prototypes */
static void _cnd_init(void);
static void _cnd_find_hash_key_for_class_id(gpointer, gpointer, gpointer);
condition *cnd_new(const char *class_id, ...) {
va_list ap;
condition *cnd = NULL;
condition *cnd_ref = NULL;
_cnd_class *cls = NULL;
char *id = NULL;
/* check if hash table is already initialized */
_cnd_init();
/* get class structure for this id */
if ((cls = (_cnd_class *)g_hash_table_lookup(classes, class_id)) == NULL) {
g_warning("cnd_new: Couldn't find class ID \"%s\"", class_id);
return NULL;
}
/* initialize the basic structure */
if ((cnd_ref = (condition *)g_malloc(sizeof(condition))) == NULL)
return NULL;
cnd_ref->user_data = NULL;
cnd_ref->eval_func = cls->eval_func;
cnd_ref->reset_func = cls->reset_func;
cnd_ref->class_id = g_strdup(class_id);
/* perform class specific initialization */
va_start(ap, class_id);
cnd = (cls->constr_func)(cnd_ref, ap);
va_end(ap);
/* check for successful construction */
if (cnd == NULL) {
g_free(cnd_ref);
g_free(id);
}
return cnd;
} /* END cnd_new() */
void cnd_delete(condition *cnd) {
_cnd_class *cls = NULL;
const char* class_id;
/* check for valid pointer */
if (cnd == NULL)
return;
class_id = cnd->class_id;
/* check if hash table is already initialized */
_cnd_init();
/* get the condition class */
cls = (_cnd_class *)g_hash_table_lookup(classes, class_id);
/* call class specific destructor */
if (cls != NULL)
(cls->destr_func)(cnd);
/* free memory */
g_free(cnd->class_id);
/* free basic structure */
g_free(cnd);
} /* END cnd_delete() */
gboolean cnd_eval(condition *cnd, ...) {
va_list ap;
gboolean ret_val = FALSE;
/* validate cnd */
if (cnd == NULL)
return FALSE;
/* call specific handler */
va_start(ap, cnd);
ret_val = (cnd->eval_func)(cnd, ap);
va_end(ap);
return ret_val;
} /* END cnd_eval() */
void cnd_reset(condition *cnd) {
if (cnd != NULL)
(cnd->reset_func)(cnd);
} /* END cnd_reset() */
void* cnd_get_user_data(condition *cnd) {
return cnd->user_data;
} /* END cnd_get_user_data() */
void cnd_set_user_data(condition *cnd, void *user_data) {
cnd->user_data = user_data;
} /* END cnd_set_user_data() */
gboolean cnd_register_class(const char *class_id,
_cnd_constr constr_func,
_cnd_destr destr_func,
_cnd_eval eval_func,
_cnd_reset reset_func) {
char *key = NULL;
_cnd_class *cls = NULL;
/* check for valid parameters */
if ((constr_func == NULL) || (destr_func == NULL) ||
(eval_func == NULL) || (reset_func == NULL) || (class_id == NULL))
return FALSE;
/* check if hash table is already initialized */
_cnd_init();
/* check for unique class id */
if (g_hash_table_lookup(classes, class_id) != NULL) {
g_warning("cnd_register_class: Duplicate class ID \"%s\"", class_id);
return FALSE;
}
/* GHashTable keys need to be persistent for the lifetime of the hash
table. Allocate memory and copy the class id which we use as key. */
key = g_strdup(class_id);
/* initialize class structure */
if ((cls = (_cnd_class*)g_malloc(sizeof(_cnd_class))) == NULL) {
g_free(key);
return FALSE;
}
cls->constr_func = constr_func;
cls->destr_func = destr_func;
cls->eval_func = eval_func;
cls->reset_func = reset_func;
/* insert new class */
g_hash_table_insert(classes, key, cls);
return TRUE;
} /* END cnd_register_class() */
static char *pkey = NULL;
void cnd_unregister_class(const char* class_id) {
const char *key = (const char*)class_id;
_cnd_class *cls = NULL;
/* check if hash table is already initialized */
_cnd_init();
/* find the key for this class id and store it in 'pkey' */
g_hash_table_foreach(classes,
_cnd_find_hash_key_for_class_id,
(gpointer)key);
/* find the class structure for this class id */
cls = (_cnd_class*)g_hash_table_lookup(classes, class_id);
/* remove constructor from hash table */
g_hash_table_remove(classes, class_id);
/* free the key */
g_free(pkey);
pkey = NULL;
/* free the value */
g_free(cls);
} /* END cnd_unregister_class() */
/*
* Initialize hash table.
*/
static void _cnd_init(void) {
if (classes != NULL)
return;
/* create hash table, we use strings as keys */
classes = g_hash_table_new(g_str_hash, g_str_equal);
} /* END _cnd_init() */
/*
* Callback for function 'g_hash_table_foreach()'.
* We don't keep references to hash table keys. Keys have memory allocated
* which must be freed when they are not used anymore. This function finds
* the reference to a key corresponding to a particular class id. The reference
* to the key is stored in a global variable.
*/
void _cnd_find_hash_key_for_class_id(gpointer key,
gpointer value _U_,
gpointer user_data) {
char *class_id = (char *)user_data;
char *key_value = (char *)key;
if (strcmp(class_id, key_value) == 0)
pkey = key_value;
} /* END _cnd_find_hash_key_for_class_id() */
/*
* Editor modelines
*
* Local Variables:
* c-basic-offset: 2
* tab-width: 8
* indent-tabs-mode: nil
* End:
*
* ex: set shiftwidth=2 tabstop=8 expandtab:
* :indentSize=2:tabSize=8:noTabs=true:
*/
|