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 "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 Wireshark starts dissecting the next packet in the list.
35 * Everytime Wireshark 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]Wireshark 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))
72 /* allocates with a packet lifetime scope an array of type made of num elements,
73 * initialised to zero.
75 #define ep_alloc_array0(type,num) (type*)ep_alloc0(sizeof(type)*(num))
78 * Splits a string into a maximum of max_tokens pieces, using the given
79 * delimiter. If max_tokens is reached, the remainder of string is appended
80 * to the last token. Consecutive delimiters are treated as a single delimiter.
82 * the vector and all the strings are allocated with packet lifetime scope
84 gchar** ep_strsplit(const gchar* string, const gchar* delimiter, int max_tokens);
86 /* release all memory allocated in the previous packet dissector */
87 void ep_free_all(void);
90 /* a stack implemented using ephemeral allocators */
92 typedef struct _ep_stack_frame_t** ep_stack_t;
94 struct _ep_stack_frame_t {
96 struct _ep_stack_frame_t* below;
97 struct _ep_stack_frame_t* above;
101 * creates an empty stack with a packet lifetime scope
103 ep_stack_t ep_stack_new(void);
106 * pushes item into stack, returns item
108 void* ep_stack_push(ep_stack_t stack, void* item);
111 * pops an item from the stack
113 void* ep_stack_pop(ep_stack_t stack);
116 * returns the item on top of the stack without popping it
118 #define ep_stack_peek(stack) ((*(stack))->payload)
121 /* Functions for handling memory allocation and garbage collection with
122 * a capture lifetime scope.
123 * These functions are used to allocate memory that will only remain persistent
124 * until Wireshark opens a new capture or capture file.
125 * Everytime Wireshark starts a new capture or opens a new capture file
126 * all the data allocated through these functions will be released back
129 * These functions are very fast and offer automatic garbage collection.
131 /* Initialize capture-lifetime memory allocation pool. This function is called
132 * once when [t]Wireshark is initialized to set up the required structures.
134 void se_init_chunk(void);
136 /* Allocate memory with a capture lifetime scope */
137 void *se_alloc(size_t size);
139 /* Allocate memory with a capture lifetime scope and fill it with zeros*/
140 void* se_alloc0(size_t size);
142 /* Duplicate a string with a capture lifetime scope */
143 gchar* se_strdup(const gchar* src);
145 /* Duplicate at most n characters of a string with a capture lifetime scope */
146 gchar* se_strndup(const gchar* src, size_t len);
148 /* Duplicate a buffer with a capture lifetime scope */
149 void* se_memdup(const void* src, size_t len);
151 /* Create a formatted string with a capture lifetime scope */
152 gchar* se_strdup_vprintf(const gchar* fmt, va_list ap);
153 gchar* se_strdup_printf(const gchar* fmt, ...)
154 GNUC_FORMAT_CHECK(printf, 1, 2);
156 /* allocates with a capture lifetime scope an array of type made of num elements */
157 #define se_alloc_array(type,num) (type*)se_alloc(sizeof(type)*(num))
159 /* release all memory allocated */
160 void se_free_all(void);
165 /**************************************************************
167 **************************************************************/
168 typedef struct _emem_tree_node_t {
169 struct _emem_tree_node_t *parent;
170 struct _emem_tree_node_t *left;
171 struct _emem_tree_node_t *right;
173 #define EMEM_TREE_RB_COLOR_RED 0
174 #define EMEM_TREE_RB_COLOR_BLACK 1
176 #define EMEM_TREE_NODE_IS_DATA 0
177 #define EMEM_TREE_NODE_IS_SUBTREE 1
178 guint32 is_subtree:1;
184 /* Right now we only do basic red/black trees but in the future we might want
185 * to try something different, such as a tree where each node keeps track
186 * of how many times it has been looked up, and letting often looked up
187 * nodes bubble upwards in the tree using rotate_right/left.
188 * That would probably be good for things like nfs filehandles
190 #define EMEM_TREE_TYPE_RED_BLACK 1
191 typedef struct _emem_tree_t {
192 struct _emem_tree_t *next;
194 const char *name; /* just a string to make debugging easier */
195 emem_tree_node_t *tree;
196 void *(*malloc)(size_t);
199 /* *******************************************************************
200 * Tree functions for SE memory allocation scope
201 * ******************************************************************* */
202 /* This function is used to create a se based tree with monitoring.
203 * When the SE heap is released back to the system the pointer to the
204 * tree is automatically reset to NULL.
206 * type is : EMEM_TREE_TYPE_RED_BLACK for a standard red/black tree.
208 emem_tree_t *se_tree_create(int type, const char *name);
210 /* This function is similar to the se_tree_create() call but with the
211 * difference that when the se memory is release everything including the
212 * pointer to the tree itself will be released.
213 * This tree will not be just reset to zero it will be completely forgotten
215 * Use this function for when you want to store the pointer to a tree inside
216 * another structure that is also se allocated so that when the structure is
217 * released, the tree will be completely released as well.
219 emem_tree_t *se_tree_create_non_persistent(int type, const char *name);
222 * Insert data into the tree and key it by a 32bit integer value
224 #define se_tree_insert32 emem_tree_insert32
227 * Retrieve the data at the search key. the search key is a 32bit integer value
229 #define se_tree_lookup32 emem_tree_lookup32
231 /* se_tree_lookup32_le
232 * Retrieve the data for the largest key that is less than or equal
235 #define se_tree_lookup32_le emem_tree_lookup32_le
237 /* se_tree_insert32_array
238 * Insert data into the tree and key it by a 32bit integer value
240 #define se_tree_insert32_array emem_tree_insert32_array
242 /* se_tree_lookup32_array
243 * Lookup data from the tree that is index by an array
245 #define se_tree_lookup32_array emem_tree_lookup32_array
249 /* Create a new string based hash table */
250 #define se_tree_create_string() se_tree_create(SE_TREE_TYPE_RED_BLACK)
252 /* Insert a new value under a string key */
253 #define se_tree_insert_string emem_tree_insert_string
255 /* Lookup the value under a string key */
256 #define se_tree_lookup_string emem_tree_lookup_string
258 /* Traverse a tree */
259 #define se_tree_foreach emem_tree_foreach
262 /* *******************************************************************
263 * Tree functions for PE memory allocation scope
264 * ******************************************************************* */
265 /* These trees have PErmanent allocation scope and will never be released
267 emem_tree_t *pe_tree_create(int type, const char *name);
268 #define pe_tree_insert32 emem_tree_insert32
269 #define pe_tree_lookup32 emem_tree_lookup32
270 #define pe_tree_lookup32_le emem_tree_lookup32_le
271 #define pe_tree_insert32_array emem_tree_insert32_array
272 #define pe_tree_lookup32_array emem_tree_lookup32_array
273 #define pe_tree_insert_string emem_tree_insert_string
274 #define pe_tree_lookup_string emem_tree_lookup_string
275 #define pe_tree_foreach emem_tree_foreach
279 /* ******************************************************************
280 * Real tree functions
281 * ****************************************************************** */
283 /* This function is used to insert a node indexed by a guint32 key value.
284 * The data pointer should be allocated by the appropriate storage scope
285 * so that it will be released at the same time as the tree itself is
288 void emem_tree_insert32(emem_tree_t *se_tree, guint32 key, void *data);
290 /* This function will look up a node in the tree indexed by a guint32 integer
293 void *emem_tree_lookup32(emem_tree_t *se_tree, guint32 key);
295 /* This function will look up a node in the tree indexed by a guint32 integer
297 * The function will return the node that has the largest key that is
298 * equal to or smaller than the search key, or NULL if no such key was
301 void *emem_tree_lookup32_le(emem_tree_t *se_tree, guint32 key);
303 typedef struct _emem_tree_key_t {
304 guint32 length; /*length in guint32 words */
308 /* This function is used to insert a node indexed by a sequence of guint32
310 * The data pointer should be allocated by SE allocators so that the
311 * data will be released at the same time as the tree itself is destroyed.
313 * Note: all the "key" members of the "key" argument MUST be aligned on
314 * 32-bit boundaries; otherwise, this code will crash on platforms such
315 * as SPARC that require aligned pointers.
317 * If you use ...32_array() calls you MUST make sure that every single node
318 * you add to a specific tree always has a key of exactly the same number of
319 * keylen words or things will most likely crash. Or at least that every single
320 * item that sits behind the same top level node always have exactly the same
323 * One way to guarantee this is the way that NFS does this for the
324 * nfs_name_snoop_known tree which holds filehandles for both v2 and v3.
325 * v2 filehandles are always 32 bytes (8 words) while v3 filehandles can have
326 * any length (though 32bytes are most common).
327 * The NFS dissector handles this by providing a guint32 containing the length
328 * as the very first item in this vector :
330 * emem_tree_key_t fhkey[3];
332 * fhlen=nns->fh_length;
334 * fhkey[0].key=&fhlen;
335 * fhkey[1].length=fhlen/4;
336 * fhkey[1].key=nns->fh;
339 void emem_tree_insert32_array(emem_tree_t *se_tree, emem_tree_key_t *key, void *data);
341 /* This function will look up a node in the tree indexed by a sequence of
342 * guint32 integer values.
344 void *emem_tree_lookup32_array(emem_tree_t *se_tree, emem_tree_key_t *key);
346 /* case insensitive strings as keys */
347 #define EMEM_TREE_STRING_NOCASE 0x00000001
348 /* Insert a new value under a string key */
349 void emem_tree_insert_string(emem_tree_t* h, const gchar* k, void* v, guint32 flags);
351 /* Lookup the value under a string key */
352 void* emem_tree_lookup_string(emem_tree_t* h, const gchar* k, guint32 flags);
355 /* traverse a tree. if the callback returns TRUE the traversal will end */
356 typedef gboolean (*tree_foreach_func)(void *value, void *userdata);
358 gboolean emem_tree_foreach(emem_tree_t* emem_tree, tree_foreach_func callback, void *user_data);
361 /* ******************************************************************
362 * String buffers - Growable strings similar to GStrings
363 * ****************************************************************** */
365 typedef struct _emem_strbuf_t {
366 gchar *str; /* points to the character data. It may move as text is */
367 /* added. The str field is nul-terminated and so can */
368 /* be used as an ordinary C string. */
369 gsize len; /* strlen: ie: length of str not including trailing '\0' */
370 gsize alloc_len; /* num bytes curently allocated for str: 1 .. MAX_STRBUF_LEN */
371 gsize max_alloc_len; /* max num bytes to allocate for str: 1 .. MAX_STRBUF_LEN */
375 * The maximum length is limited to 64K. If you need something bigger, you
376 * should probably use an actual GString or GByteArray.
380 * Allocate an ephemeral string buffer with "unlimited" size.
382 * @param init The initial string for the buffer, or NULL to allocate an initial zero-length string.
384 * @return A newly-allocated string buffer.
386 emem_strbuf_t *ep_strbuf_new(const gchar *init);
389 * Allocate an ephemeral string buffer suitable for the protocol tree.
390 * The string will never grow beyond the maximum tree item length.
392 * @param init The initial string for the buffer, or NULL to allocate an initial zero-length string.
394 * @return A newly-allocated string buffer.
396 emem_strbuf_t *ep_strbuf_new_label(const gchar *init);
399 * Allocate an ephemeral string buffer with enough initial space for @alloc_len bytes
400 * and a maximum of @max_alloc_len bytes.
402 * @param alloc_len The initial size of the buffer. This value can be 0, but a nonzero
403 * value is recommended.
404 * @param max_alloc_len The maximum size of the buffer. 0 means "unlimited" (within
407 * @return A newly-allocated string buffer. @str will be empty.
409 emem_strbuf_t *ep_strbuf_sized_new(gsize alloc_len, gsize max_alloc_len);
412 * Append vprintf-style formatted text to a string buffer.
414 * @param strbuf The ep_strbuf-allocated string buffer to append to.
415 * @param format A printf-style string format.
416 * @param args The list of arguments to append.
418 void ep_strbuf_append_vprintf(emem_strbuf_t *strbuf, const gchar *format, va_list ap);
421 * Apply printf-style formatted text to a string buffer.
423 * @param strbuf The ep_strbuf-allocated string buffer to set to.
424 * @param format A printf-style string format.
426 void ep_strbuf_printf(emem_strbuf_t *strbuf, const gchar *format, ...)
427 GNUC_FORMAT_CHECK(printf, 2, 3);
430 * Append printf-style formatted text to a string buffer.
432 * @param strbuf The ep_strbuf-allocated string buffer to append to.
433 * @param format A printf-style string format.
435 void ep_strbuf_append_printf(emem_strbuf_t *strbuf, const gchar *format, ...)
436 GNUC_FORMAT_CHECK(printf, 2, 3);
439 * Append a string to a string buffer.
441 * @param strbuf The ep_strbuf-allocated string buffer to append to.
442 * @param str A null-terminated string.
446 emem_strbuf_t *ep_strbuf_append(emem_strbuf_t *strbuf, const gchar *str);
449 * Append a character to a string buffer.
451 * @param strbuf The ep_strbuf-allocated string buffer to append to.
452 * @param c The character to append.
456 emem_strbuf_t *ep_strbuf_append_c(emem_strbuf_t *strbuf, const gchar c);
459 * Chop off the end of a string buffer.
461 * @param strbuf The ep_strbuf-allocated string buffer to append to.
462 * @param len The new string length.
466 emem_strbuf_t *ep_strbuf_truncate(emem_strbuf_t *strbuf, gsize len);
468 void emem_print_tree(emem_tree_t* emem_tree);
470 /* #define DEBUG_INTENSE_CANARY_CHECKS */
471 /* Helper to troubleshoot ep memory corruption
472 * if compiled and the environment variable WIRESHARK_DEBUG_EP_INTENSE_CANARY exists
473 * it will check the canaries and when found corrupt stop there in the hope
474 * the corruptor is still there in the stack.
475 * Some checkpoints are already set in packet.c in strategic points
476 * before and after dissection of a frame or a dissector call.
479 #ifdef DEBUG_INTENSE_CANARY_CHECKS
480 void ep_check_canary_integrity(const char* fmt, ...);
481 #define EP_CHECK_CANARY(sprintf_args) ep_check_canary_integrity sprintf_args
483 #define EP_CHECK_CANARY(dummy)
487 * Verify that the given pointer is of ephemeral/seasonal type.
489 * @param ptr The pointer to verify
491 * @return TRUE if the pointer belongs to the ephemeral/seasonal pool.
493 gboolean ep_verify_pointer(const void *ptr);
494 gboolean se_verify_pointer(const void *ptr);