2 * Definitions for ethereal memory management and garbage collection
7 * Wireshark - Network traffic analyzer
8 * By Gerald Combs <gerald@wireshark.org>
9 * Copyright 1998 Gerald Combs
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version 2
14 * of the License, or (at your option) any later version.
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
29 #include "gnuc_format_check.h"
31 /* Functions for handling memory allocation and garbage collection with
32 * a packet lifetime scope.
33 * These functions are used to allocate memory that will only remain persistent
34 * until ethereal starts dissecting the next packet in the list.
35 * Everytime ethereal starts decoding the next packet all memory allocated
36 * through these functions will be released back to the free pool.
38 * These functions are very fast and offer automatic garbage collection:
39 * Everytime a new packet is dissected, all memory allocations done in
40 * the previous packet is freed.
42 /* Initialize packet-lifetime memory allocation pool. This function is called
43 * once when [t]ethereal is initialized to set up the required structures.
45 void ep_init_chunk(void);
47 /* Allocate memory with a packet lifetime scope */
48 void *ep_alloc(size_t size);
49 #define ep_new(type) ((type*)ep_alloc(sizeof(type)))
51 /* Allocate memory with a packet lifetime scope and fill it with zeros*/
52 void* ep_alloc0(size_t size);
53 #define ep_new0(type) ((type*)ep_alloc0(sizeof(type)))
55 /* Duplicate a string with a packet lifetime scope */
56 gchar* ep_strdup(const gchar* src);
58 /* Duplicate at most n characters of a string with a packet lifetime scope */
59 gchar* ep_strndup(const gchar* src, size_t len);
61 /* Duplicate a buffer with a packet lifetime scope */
62 void* ep_memdup(const void* src, size_t len);
64 /* Create a formatted string with a packet lifetime scope */
65 gchar* ep_strdup_vprintf(const gchar* fmt, va_list ap);
66 gchar* ep_strdup_printf(const gchar* fmt, ...)
67 GNUC_FORMAT_CHECK(printf, 1, 2);
69 /* allocates with a packet lifetime scope an array of type made of num elements */
70 #define ep_alloc_array(type,num) (type*)ep_alloc(sizeof(type)*(num))
73 * Splits a string into a maximum of max_tokens pieces, using the given
74 * delimiter. If max_tokens is reached, the remainder of string is appended
75 * to the last token. Consecutive delimiters are treated as a single delimiter.
77 * the vector and all the strings are allocated with packet lifetime scope
79 gchar** ep_strsplit(const gchar* string, const gchar* delimiter, int max_tokens);
81 /* release all memory allocated in the previous packet dissector */
82 void ep_free_all(void);
85 /* a stack implemented using ephemeral allocators */
87 typedef struct _ep_stack_frame_t** ep_stack_t;
89 struct _ep_stack_frame_t {
91 struct _ep_stack_frame_t* below;
92 struct _ep_stack_frame_t* above;
96 * creates an empty stack with a packet lifetime scope
98 ep_stack_t ep_stack_new(void);
101 * pushes item into stack, returns item
103 void* ep_stack_push(ep_stack_t stack, void* item);
106 * pops an item from the stack
108 void* ep_stack_pop(ep_stack_t stack);
111 * returns the item on top of the stack without popping it
113 #define ep_stack_peek(stack) ((*(stack))->payload)
116 /* Functions for handling memory allocation and garbage collection with
117 * a capture lifetime scope.
118 * These functions are used to allocate memory that will only remain persistent
119 * until ethereal opens a new capture or capture file.
120 * Everytime ethereal starts a new capture or opens a new capture file
121 * all the data allocated through these functions will be released back
124 * These functions are very fast and offer automatic garbage collection.
126 /* Initialize capture-lifetime memory allocation pool. This function is called
127 * once when [t]ethereal is initialized to set up the required structures.
129 void se_init_chunk(void);
131 /* Allocate memory with a capture lifetime scope */
132 void *se_alloc(size_t size);
134 /* Allocate memory with a capture lifetime scope and fill it with zeros*/
135 void* se_alloc0(size_t size);
137 /* Duplicate a string with a capture lifetime scope */
138 gchar* se_strdup(const gchar* src);
140 /* Duplicate at most n characters of a string with a capture lifetime scope */
141 gchar* se_strndup(const gchar* src, size_t len);
143 /* Duplicate a buffer with a capture lifetime scope */
144 void* se_memdup(const void* src, size_t len);
146 /* Create a formatted string with a capture lifetime scope */
147 gchar* se_strdup_vprintf(const gchar* fmt, va_list ap);
148 gchar* se_strdup_printf(const gchar* fmt, ...)
149 GNUC_FORMAT_CHECK(printf, 1, 2);
151 /* allocates with a capture lifetime scope an array of type made of num elements */
152 #define se_alloc_array(type,num) (type*)se_alloc(sizeof(type)*(num))
154 /* release all memory allocated */
155 void se_free_all(void);
160 /**************************************************************
161 * binary trees with SE allocation
162 **************************************************************/
163 #define SE_TREE_RB_COLOR_RED 0x00
164 #define SE_TREE_RB_COLOR_BLACK 0x01
165 typedef struct _se_tree_node_t {
166 struct _se_tree_node_t *parent;
167 struct _se_tree_node_t *left;
168 struct _se_tree_node_t *right;
176 /* list of all se trees so they can all be reset automatically when
177 * we free all se memory
179 /* Right now we only do basic red/black trees but in the future we might want
180 * to try something different, such as a tree where each node keeps track
181 * of how many times it has been looked up, and letting often looked up
182 * nodes bubble upwards in the tree using rotate_right/left.
183 * That would probably be good for things like nfs filehandles
185 #define SE_TREE_TYPE_RED_BLACK 1
186 typedef struct _se_tree_t {
187 struct _se_tree_t *next;
189 char *name; /* just a string to make debugging easier */
190 se_tree_node_t *tree;
192 extern se_tree_t *se_trees;
195 /* This function is used to create a se based tree with monitoring.
196 * When the SE heap is released back to the system the pointer to the
197 * tree is automatically reset to NULL.
199 * type is : SE_TREE_TYPE_RED_BLACK for a standard red/black tree.
201 se_tree_t *se_tree_create(int type, char *name);
203 /* This function is used to insert a node indexed by a guint32 key value.
204 * The data pointer should be allocated by SE allocators so that the
205 * data will be released at the same time as the tree itself is destroyed.
207 void se_tree_insert32(se_tree_t *se_tree, guint32 key, void *data);
209 /* This function will look up a node in the tree indexed by a guint32 integer
212 void *se_tree_lookup32(se_tree_t *se_tree, guint32 key);
214 /* This function will look up a node in the tree indexed by a guint32 integer
216 * The function will return the node that has the largest key that is
217 * equal to or smaller than the search key, or NULL if no such key was
220 void *se_tree_lookup32_le(se_tree_t *se_tree, guint32 key);
223 /* This function is similar to the se_tree_create() call but with the
224 * difference that when the se memory is release everything including the
225 * pointer to the tree itself will be released.
226 * This tree will not be just reset to zero it will be completely forgotten
228 * Use this function for when you want to store the pointer to a tree inside
229 * another structure that is also se allocated so that when the structure is
230 * released, the tree will be completely released as well.
232 se_tree_t *se_tree_create_non_persistent(int type, char *name);
234 typedef struct _se_tree_key_t {
235 guint32 length; /*length in guint32 words */
239 /* This function is used to insert a node indexed by a sequence of guint32
241 * The data pointer should be allocated by SE allocators so that the
242 * data will be released at the same time as the tree itself is destroyed.
244 * If you use ...32_array() calls you MUST make sure that every single node
245 * you add to a specific tree always has a key of exactly the same number of
246 * keylen words or things will most likely crash. Or at least that every single
247 * item that sits behind the same top level node always have exactly the same
250 * One way to guarantee this is the way that NFS does this for the
251 * nfs_name_snoop_known tree which holds filehandles for both v2 and v3.
252 * v2 filehandles are always 32 bytes (8 words) while v3 filehandles can have
253 * any length (though 32bytes are most common).
254 * The NFS dissector handles this by providing a guint32 containing the length
255 * as the very first item in this vector :
257 * se_tree_key_t fhkey[3];
259 * fhlen=nns->fh_length;
261 * fhkey[0].key=&fhlen;
262 * fhkey[1].length=fhlen/4;
263 * fhkey[1].key=nns->fh;
266 void se_tree_insert32_array(se_tree_t *se_tree, se_tree_key_t *key, void *data);
268 /* This function will look up a node in the tree indexed by a sequence of
269 * guint32 integer values.
271 void *se_tree_lookup32_array(se_tree_t *se_tree, se_tree_key_t *key);
274 * A hash table with string keys based on the red/black tree
276 typedef struct _se_tree_t se_string_hash_t;
278 /* Create a new string based hash table */
279 #define se_tree_create_string() se_tree_create(SE_TREE_TYPE_RED_BLACK)
281 /* Insert a new value under a string key */
282 void se_tree_insert_string(se_string_hash_t* h, const gchar* k, void* v);
284 /* Lookup the value under a string key */
285 void* se_tree_lookup_string(se_string_hash_t* h, const gchar* k);