2 * Definitions for Wireshark 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 "g_gnuc_malloc.h"
31 /* Initialize all the memory allocation pools described below.
32 * This function must be called once when *shark initialize to set up the
33 * required structures.
37 /* Functions for handling memory allocation and garbage collection with
38 * a packet lifetime scope.
39 * These functions are used to allocate memory that will only remain persistent
40 * until Wireshark starts dissecting the next packet in the list.
41 * Everytime Wireshark starts decoding the next packet all memory allocated
42 * through these functions will be released back to the free pool.
44 * These functions are very fast and offer automatic garbage collection:
45 * Everytime a new packet is dissected, all memory allocations done in
46 * the previous packet is freed.
49 /* Allocate memory with a packet lifetime scope */
50 void *ep_alloc(size_t size) G_GNUC_MALLOC;
51 #define ep_new(type) ((type*)ep_alloc(sizeof(type)))
53 /* Allocate memory with a packet lifetime scope and fill it with zeros*/
54 void* ep_alloc0(size_t size) G_GNUC_MALLOC;
55 #define ep_new0(type) ((type*)ep_alloc0(sizeof(type)))
57 /* Duplicate a string with a packet lifetime scope */
58 gchar* ep_strdup(const gchar* src) G_GNUC_MALLOC;
60 /* Duplicate at most n characters of a string with a packet lifetime scope */
61 gchar* ep_strndup(const gchar* src, size_t len) G_GNUC_MALLOC;
63 /* Duplicate a buffer with a packet lifetime scope */
64 void* ep_memdup(const void* src, size_t len) G_GNUC_MALLOC;
66 /* Create a formatted string with a packet lifetime scope */
67 gchar* ep_strdup_vprintf(const gchar* fmt, va_list ap) G_GNUC_MALLOC;
68 gchar* ep_strdup_printf(const gchar* fmt, ...)
69 G_GNUC_MALLOC G_GNUC_PRINTF(1, 2);
71 /* allocates with a packet lifetime scope an array of type made of num elements */
72 #define ep_alloc_array(type,num) (type*)ep_alloc(sizeof(type)*(num))
74 /* allocates with a packet lifetime scope an array of type made of num elements,
75 * initialised to zero.
77 #define ep_alloc_array0(type,num) (type*)ep_alloc0(sizeof(type)*(num))
80 * Splits a string into a maximum of max_tokens pieces, using the given
81 * delimiter. If max_tokens is reached, the remainder of string is appended
82 * to the last token. Consecutive delimiters are treated as a single delimiter.
84 * The vector and all the strings are allocated with packet lifetime scope
86 gchar** ep_strsplit(const gchar* string, const gchar* delimiter, int max_tokens);
88 /* release all memory allocated in the previous packet dissection */
89 void ep_free_all(void);
92 /* a stack implemented using ephemeral allocators */
94 typedef struct _ep_stack_frame_t** ep_stack_t;
96 struct _ep_stack_frame_t {
98 struct _ep_stack_frame_t* below;
99 struct _ep_stack_frame_t* above;
103 * creates an empty stack with a packet lifetime scope
105 ep_stack_t ep_stack_new(void) G_GNUC_MALLOC;
108 * pushes item into stack, returns item
110 void* ep_stack_push(ep_stack_t stack, void* item);
113 * pops an item from the stack
115 void* ep_stack_pop(ep_stack_t stack);
118 * returns the item on top of the stack without popping it
120 #define ep_stack_peek(stack) ((*(stack))->payload)
123 /* Functions for handling memory allocation and garbage collection with
124 * a capture lifetime scope.
125 * These functions are used to allocate memory that will only remain persistent
126 * until Wireshark opens a new capture or capture file.
127 * Everytime Wireshark starts a new capture or opens a new capture file
128 * all the data allocated through these functions will be released back
131 * These functions are very fast and offer automatic garbage collection.
134 /* Allocate memory with a capture lifetime scope */
135 void *se_alloc(size_t size) G_GNUC_MALLOC;
137 /* Allocate memory with a capture lifetime scope and fill it with zeros*/
138 void* se_alloc0(size_t size) G_GNUC_MALLOC;
140 /* Duplicate a string with a capture lifetime scope */
141 gchar* se_strdup(const gchar* src) G_GNUC_MALLOC;
143 /* Duplicate at most n characters of a string with a capture lifetime scope */
144 gchar* se_strndup(const gchar* src, size_t len) G_GNUC_MALLOC;
146 /* Duplicate a buffer with a capture lifetime scope */
147 void* se_memdup(const void* src, size_t len) G_GNUC_MALLOC;
149 /* Create a formatted string with a capture lifetime scope */
150 gchar* se_strdup_vprintf(const gchar* fmt, va_list ap) G_GNUC_MALLOC;
151 gchar* se_strdup_printf(const gchar* fmt, ...)
152 G_GNUC_MALLOC G_GNUC_PRINTF(1, 2);
154 /* allocates with a capture lifetime scope an array of type made of num elements */
155 #define se_alloc_array(type,num) (type*)se_alloc(sizeof(type)*(num))
157 /* release all memory allocated */
158 void se_free_all(void);
163 /**************************************************************
165 **************************************************************/
166 typedef struct _emem_tree_node_t {
167 struct _emem_tree_node_t *parent;
168 struct _emem_tree_node_t *left;
169 struct _emem_tree_node_t *right;
171 #define EMEM_TREE_RB_COLOR_RED 0
172 #define EMEM_TREE_RB_COLOR_BLACK 1
174 #define EMEM_TREE_NODE_IS_DATA 0
175 #define EMEM_TREE_NODE_IS_SUBTREE 1
176 guint32 is_subtree:1;
182 /* Right now we only do basic red/black trees but in the future we might want
183 * to try something different, such as a tree where each node keeps track
184 * of how many times it has been looked up, and letting often looked up
185 * nodes bubble upwards in the tree using rotate_right/left.
186 * That would probably be good for things like nfs filehandles
188 #define EMEM_TREE_TYPE_RED_BLACK 1
189 typedef struct _emem_tree_t {
190 struct _emem_tree_t *next;
192 const char *name; /* just a string to make debugging easier */
193 emem_tree_node_t *tree;
194 void *(*malloc)(size_t);
197 /* *******************************************************************
198 * Tree functions for SE memory allocation scope
199 * ******************************************************************* */
200 /* This function is used to create a se based tree with monitoring.
201 * When the SE heap is released back to the system the pointer to the
202 * tree is automatically reset to NULL.
204 * type is : EMEM_TREE_TYPE_RED_BLACK for a standard red/black tree.
206 emem_tree_t *se_tree_create(int type, const char *name) G_GNUC_MALLOC;
208 /* This function is similar to the se_tree_create() call but with the
209 * difference that when the se memory is released everything including the
210 * pointer to the tree itself will be released.
211 * This tree will not be just reset to zero, it will be completely forgotten
213 * Use this function for when you want to store the pointer to a tree inside
214 * another structure that is also se allocated so that when the structure is
215 * released, the tree will be completely released as well.
217 emem_tree_t *se_tree_create_non_persistent(int type, const char *name) G_GNUC_MALLOC;
220 * Insert data into the tree and key it by a 32bit integer value
222 #define se_tree_insert32 emem_tree_insert32
225 * Retrieve the data at the search key. The search key is a 32bit integer value
227 #define se_tree_lookup32 emem_tree_lookup32
229 /* se_tree_lookup32_le
230 * Retrieve the data for the largest key that is less than or equal
233 #define se_tree_lookup32_le emem_tree_lookup32_le
235 /* se_tree_insert32_array
236 * Insert data into the tree and key it by a 32bit integer value
238 #define se_tree_insert32_array emem_tree_insert32_array
240 /* se_tree_lookup32_array
241 * Lookup data from the tree that is index by an array
243 #define se_tree_lookup32_array emem_tree_lookup32_array
245 /* se_tree_lookup32_array_le
246 * Retrieve the data for the largest key that is less than or equal
249 #define se_tree_lookup32_array_le emem_tree_lookup32_array_le
251 /* Create a new string based hash table */
252 #define se_tree_create_string() se_tree_create(SE_TREE_TYPE_RED_BLACK)
254 /* Insert a new value under a string key */
255 #define se_tree_insert_string emem_tree_insert_string
257 /* Lookup the value under a string key */
258 #define se_tree_lookup_string emem_tree_lookup_string
260 /* Traverse a tree */
261 #define se_tree_foreach emem_tree_foreach
264 /* *******************************************************************
265 * Tree functions for PE memory allocation scope
266 * ******************************************************************* */
267 /* These trees have PErmanent allocation scope and will never be released
269 emem_tree_t *pe_tree_create(int type, const char *name) G_GNUC_MALLOC;
270 #define pe_tree_insert32 emem_tree_insert32
271 #define pe_tree_lookup32 emem_tree_lookup32
272 #define pe_tree_lookup32_le emem_tree_lookup32_le
273 #define pe_tree_insert32_array emem_tree_insert32_array
274 #define pe_tree_lookup32_array emem_tree_lookup32_array
275 #define pe_tree_insert_string emem_tree_insert_string
276 #define pe_tree_lookup_string emem_tree_lookup_string
277 #define pe_tree_foreach emem_tree_foreach
281 /* ******************************************************************
282 * Real tree functions
283 * ****************************************************************** */
285 /* This function is used to insert a node indexed by a guint32 key value.
286 * The data pointer should be allocated by the appropriate storage scope
287 * so that it will be released at the same time as the tree itself is
290 void emem_tree_insert32(emem_tree_t *se_tree, guint32 key, void *data);
292 /* This function will look up a node in the tree indexed by a guint32 integer
295 void *emem_tree_lookup32(emem_tree_t *se_tree, guint32 key);
297 /* This function will look up a node in the tree indexed by a guint32 integer
299 * The function will return the node that has the largest key that is
300 * equal to or smaller than the search key, or NULL if no such key was
303 void *emem_tree_lookup32_le(emem_tree_t *se_tree, guint32 key);
305 typedef struct _emem_tree_key_t {
306 guint32 length; /*length in guint32 words */
310 /* This function is used to insert a node indexed by a sequence of guint32
312 * The data pointer should be allocated by SE allocators so that the
313 * data will be released at the same time as the tree itself is destroyed.
315 * Note: all the "key" members of the "key" argument MUST be aligned on
316 * 32-bit boundaries; otherwise, this code will crash on platforms such
317 * as SPARC that require aligned pointers.
319 * If you use ...32_array() calls you MUST make sure that every single node
320 * you add to a specific tree always has a key of exactly the same number of
321 * keylen words or things will most likely crash. Or at least that every single
322 * item that sits behind the same top level node always have exactly the same
325 * One way to guarantee this is the way that NFS does this for the
326 * nfs_name_snoop_known tree which holds filehandles for both v2 and v3.
327 * v2 filehandles are always 32 bytes (8 words) while v3 filehandles can have
328 * any length (though 32 bytes are most common).
329 * The NFS dissector handles this by providing a guint32 containing the length
330 * as the very first item in this vector :
332 * emem_tree_key_t fhkey[3];
334 * fhlen=nns->fh_length;
336 * fhkey[0].key=&fhlen;
337 * fhkey[1].length=fhlen/4;
338 * fhkey[1].key=nns->fh;
341 void emem_tree_insert32_array(emem_tree_t *se_tree, emem_tree_key_t *key, void *data);
343 /* This function will look up a node in the tree indexed by a sequence of
344 * guint32 integer values.
346 void *emem_tree_lookup32_array(emem_tree_t *se_tree, emem_tree_key_t *key);
348 /* This function will look up a node in the tree indexed by a
349 * multi-part tree value.
350 * The function will return the node that has the largest key that is
351 * equal to or smaller than the search key, or NULL if no such key was
353 * Note: The key returned will be "less" in key order. The usefullness
354 * of the returned node must be verified prior to use.
356 void *emem_tree_lookup32_array_le(emem_tree_t *se_tree, emem_tree_key_t *key);
358 /* case insensitive strings as keys */
359 #define EMEM_TREE_STRING_NOCASE 0x00000001
360 /* Insert a new value under a string key */
361 void emem_tree_insert_string(emem_tree_t* h, const gchar* k, void* v, guint32 flags);
363 /* Lookup the value under a string key */
364 void* emem_tree_lookup_string(emem_tree_t* h, const gchar* k, guint32 flags);
367 /* traverse a tree. if the callback returns TRUE the traversal will end */
368 typedef gboolean (*tree_foreach_func)(void *value, void *userdata);
370 gboolean emem_tree_foreach(emem_tree_t* emem_tree, tree_foreach_func callback, void *user_data);
373 /* ******************************************************************
374 * String buffers - Growable strings similar to GStrings
375 * ****************************************************************** */
377 typedef struct _emem_strbuf_t {
378 gchar *str; /* Points to the character data. It may move as text is */
379 /* added. The str field is null-terminated and so can */
380 /* be used as an ordinary C string. */
381 gsize len; /* strlen: ie: length of str not including trailing '\0' */
382 gsize alloc_len; /* num bytes curently allocated for str: 1 .. MAX_STRBUF_LEN */
383 gsize max_alloc_len; /* max num bytes to allocate for str: 1 .. MAX_STRBUF_LEN */
387 * The maximum length is limited to 64K. If you need something bigger, you
388 * should probably use an actual GString or GByteArray.
392 * Allocate an ephemeral string buffer with "unlimited" size.
394 * @param init The initial string for the buffer, or NULL to allocate an initial zero-length string.
396 * @return A newly-allocated string buffer.
398 emem_strbuf_t *ep_strbuf_new(const gchar *init) G_GNUC_MALLOC;
401 * Allocate an ephemeral string buffer suitable for the protocol tree.
402 * The string will never grow beyond the maximum tree item length.
404 * @param init The initial string for the buffer, or NULL to allocate an initial zero-length string.
406 * @return A newly-allocated string buffer.
408 emem_strbuf_t *ep_strbuf_new_label(const gchar *init) G_GNUC_MALLOC;
411 * Allocate an ephemeral string buffer with enough initial space for @alloc_len bytes
412 * and a maximum of @max_alloc_len bytes.
414 * @param alloc_len The initial size of the buffer. This value can be 0, but a nonzero
415 * value is recommended.
416 * @param max_alloc_len The maximum size of the buffer. 0 means "unlimited" (within
419 * @return A newly-allocated string buffer. @str will be empty.
421 emem_strbuf_t *ep_strbuf_sized_new(gsize alloc_len, gsize max_alloc_len) G_GNUC_MALLOC;
424 * Append vprintf-style formatted text to a string buffer.
426 * @param strbuf The ep_strbuf-allocated string buffer to append to.
427 * @param format A printf-style string format.
428 * @param args The list of arguments to append.
430 void ep_strbuf_append_vprintf(emem_strbuf_t *strbuf, const gchar *format, va_list ap);
433 * Apply printf-style formatted text to a string buffer.
435 * @param strbuf The ep_strbuf-allocated string buffer to set to.
436 * @param format A printf-style string format.
438 void ep_strbuf_printf(emem_strbuf_t *strbuf, const gchar *format, ...)
442 * Append printf-style formatted text to a string buffer.
444 * @param strbuf The ep_strbuf-allocated string buffer to append to.
445 * @param format A printf-style string format.
447 void ep_strbuf_append_printf(emem_strbuf_t *strbuf, const gchar *format, ...)
451 * Append a string to a string buffer.
453 * @param strbuf The ep_strbuf-allocated string buffer to append to.
454 * @param str A null-terminated string.
458 emem_strbuf_t *ep_strbuf_append(emem_strbuf_t *strbuf, const gchar *str);
461 * Append a character to a string buffer.
463 * @param strbuf The ep_strbuf-allocated string buffer to append to.
464 * @param c The character to append.
468 emem_strbuf_t *ep_strbuf_append_c(emem_strbuf_t *strbuf, const gchar c);
471 * Chop off the end of a string buffer.
473 * @param strbuf The ep_strbuf-allocated string buffer to append to.
474 * @param len The new string length.
478 emem_strbuf_t *ep_strbuf_truncate(emem_strbuf_t *strbuf, gsize len);
480 void emem_print_tree(emem_tree_t* emem_tree);
482 /* #define DEBUG_INTENSE_CANARY_CHECKS */
484 /* Helper to troubleshoot ep memory corruption.
485 * If compiled and the environment variable WIRESHARK_DEBUG_EP_INTENSE_CANARY exists
486 * it will check the canaries and when found corrupt stop there in the hope
487 * the corruptor is still there in the stack.
488 * Some checkpoints are already set in packet.c in strategic points
489 * before and after dissection of a frame or a dissector call.
492 #ifdef DEBUG_INTENSE_CANARY_CHECKS
493 void ep_check_canary_integrity(const char* fmt, ...)
495 #define EP_CHECK_CANARY(args) ep_check_canary_integrity args
497 #define EP_CHECK_CANARY(args)
501 * Verify that the given pointer is of ephemeral/seasonal type.
503 * @param ptr The pointer to verify
505 * @return TRUE if the pointer belongs to the ephemeral/seasonal pool.
507 gboolean ep_verify_pointer(const void *ptr);
508 gboolean se_verify_pointer(const void *ptr);