-
/* tvbparse.h
*
* an API for text tvb parsers
* 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
/*
The intention behind this is to ease the writing of dissectors that have to
parse text without the need of writing into buffers.
-
+
It was originally written to avoid using lex and yacc for the xml dissector.
-
+
the parser is able to look for wanted elements these can be:
-
+
simple tokens:
- a char out of a string of needles
- a char not belonging to a string of needles
- a string
- a caseless string
- all the characters up to a certain wanted element (included or excluded)
-
+
composed elements:
- one of a given group of wanted elements
- a sequence of wanted elements
- some (at least one) instances of a wanted element
-
+
Once a wanted element is successfully extracted, by either tvbparse_get or
- tvbparse_find, the parser will invoke a given callback
+ tvbparse_find, the parser will invoke a given callback
before and another one after every of its component's subelement's callbacks
are being called.
-
+
If tvbparse_get or tvbparse_find fail to extract the wanted element the
subelements callbacks are not going to be invoked.
-
+
The wanted elements are instantiated once by the proto_register_xxx function.
-
+
The parser is instantiated for every packet and it mantains its state.
-
+
The element's data is destroyed before the next packet is dissected.
*/
typedef void (*tvbparse_action_t)(void* tvbparse_data, const void* wanted_data, struct _tvbparse_elem_t* elem);
typedef int (*tvbparse_condition_t)
-(tvbparse_t*, int,
- const tvbparse_wanted_t*,
+(tvbparse_t*, const int,
+ const tvbparse_wanted_t*,
tvbparse_elem_t**);
struct _tvbparse_wanted_t {
int id;
- tvbparse_condition_t condition;
-
+ tvbparse_condition_t condition;
+
union {
- const gchar* str;
- struct _tvbparse_wanted_t** handle;
- struct {
- union {
- gint64 i;
- guint64 u;
- gdouble f;
- } value;
- gboolean (*comp)(void*,const void*);
- void* (*extract)(tvbuff_t*,guint);
- } number;
- enum ftenum ftenum;
- struct {
- until_mode_t mode;
- const tvbparse_wanted_t* subelem;
- } until;
- struct {
- GHashTable* table;
- struct _tvbparse_wanted_t* key;
- struct _tvbparse_wanted_t* other;
- } hash;
- GPtrArray* elems;
- const tvbparse_wanted_t* subelem;
- void* p;
- } control;
-
+ const gchar* str;
+ struct _tvbparse_wanted_t** handle;
+ struct {
+ union {
+ gint64 i;
+ guint64 u;
+ gdouble f;
+ } value;
+ gboolean (*comp)(void*,const void*);
+ void* (*extract)(tvbuff_t*,guint);
+ } number;
+ enum ftenum ftenum;
+ struct {
+ until_mode_t mode;
+ const tvbparse_wanted_t* subelem;
+ } until;
+ struct {
+ GHashTable* table;
+ struct _tvbparse_wanted_t* key;
+ struct _tvbparse_wanted_t* other;
+ } hash;
+ GPtrArray* elems;
+ const tvbparse_wanted_t* subelem;
+ void* p;
+ } control;
+
int len;
-
+
guint min;
guint max;
-
+
const void* data;
-
+
tvbparse_action_t before;
tvbparse_action_t after;
-
};
/* an instance of a per packet parser */
struct _tvbparse_t {
tvbuff_t* tvb;
int offset;
- int end_offset;
+ int end_offset;
void* data;
const tvbparse_wanted_t* ignore;
};
/* a matching token returned by either tvbparser_get or tvb_parser_find */
struct _tvbparse_elem_t {
int id;
-
+
tvbuff_t* tvb;
int offset;
int len;
-
+
void* data;
-
+
struct _tvbparse_elem_t* sub;
-
+
struct _tvbparse_elem_t* next;
struct _tvbparse_elem_t* last;
-
+
const tvbparse_wanted_t* wanted;
};
* When looked for it returns a simple element one character long if the char
* at the current offset matches one of the the needles.
*/
-tvbparse_wanted_t* tvbparse_char(int id,
+tvbparse_wanted_t* tvbparse_char(const int id,
const gchar* needles,
const void* private_data,
tvbparse_action_t before_cb,
* When looked for it returns a simple element one character long if the char
* at the current offset does not match one of the the needles.
*/
-tvbparse_wanted_t* tvbparse_not_char(int id,
+tvbparse_wanted_t* tvbparse_not_char(const int id,
const gchar* needle,
const void* private_data,
tvbparse_action_t before_cb,
*
* When looked for it returns a simple element one or more characters long if
* one or more char(s) starting from the current offset match one of the needles.
- * An element will be returned if at least min_len chars are given (1 if it's 0)
+ * An element will be returned if at least min_len chars are given (1 if it's 0)
* It will get at most max_len chars or as much as it can if max_len is 0.
*/
-tvbparse_wanted_t* tvbparse_chars(int id,
- guint min_len,
- guint max_len,
+tvbparse_wanted_t* tvbparse_chars(const int id,
+ const guint min_len,
+ const guint max_len,
const gchar* needles,
const void* private_data,
tvbparse_action_t before_cb,
* When looked for it returns a simple element one or more characters long if
* one or more char(s) starting from the current offset do not match one of the
* needles.
- * An element will be returned if at least min_len chars are given (1 if it's 0)
+ * An element will be returned if at least min_len chars are given (1 if it's 0)
* It will get at most max_len chars or as much as it can if max_len is 0.
*/
-tvbparse_wanted_t* tvbparse_not_chars(int id,
- guint min_len,
- guint max_len,
+tvbparse_wanted_t* tvbparse_not_chars(const int id,
+ const guint min_len,
+ const guint max_len,
const gchar* needles,
const void* private_data,
tvbparse_action_t before_cb,
* a string element
*
* When looked for it returns a simple element if we have the given string at
- * the current offset
+ * the current offset
*/
-tvbparse_wanted_t* tvbparse_string(int id,
+tvbparse_wanted_t* tvbparse_string(const int id,
const gchar* string,
const void* private_data,
tvbparse_action_t before_cb,
* casestring
*
* When looked for it returns a simple element if we have a matching string at
- * the current offset
+ * the current offset
*/
-tvbparse_wanted_t* tvbparse_casestring(int id,
+tvbparse_wanted_t* tvbparse_casestring(const int id,
const gchar* str,
const void* data,
tvbparse_action_t before_cb,
/*
* until
*
- * When looked for it returns a simple element containing all the characters
+ * When looked for it returns a simple element containing all the characters
* found until the first match of the ending element if the ending element is
* found.
*
- * When looking for until elements it calls tvbparse_find so it can be very slow.
+ * When looking for until elements it calls tvbparse_find so it can be very slow.
*
* It won't have a subelement, the ending's callbacks won't get called.
*/
/*
* op_mode values determine how the terminating element and the current offset
- * of the parser are handled
+ * of the parser are handled
*/
-tvbparse_wanted_t* tvbparse_until(int id,
+tvbparse_wanted_t* tvbparse_until(const int id,
const void* private_data,
tvbparse_action_t before_cb,
tvbparse_action_t after_cb,
* The list of candidates is terminated with a NULL
*
*/
-tvbparse_wanted_t* tvbparse_set_oneof(int id,
+tvbparse_wanted_t* tvbparse_set_oneof(const int id,
const void* private_data,
tvbparse_action_t before_cb,
tvbparse_action_t after_cb,
...);
-/*
+/*
* hashed
*/
-
-tvbparse_wanted_t* tvbparse_hashed(int id,
- const void* data,
- tvbparse_action_t before_cb,
- tvbparse_action_t after_cb,
- tvbparse_wanted_t* key,
- tvbparse_wanted_t* other,
- ...);
+tvbparse_wanted_t* tvbparse_hashed(const int id,
+ const void* data,
+ tvbparse_action_t before_cb,
+ tvbparse_action_t after_cb,
+ tvbparse_wanted_t* key,
+ tvbparse_wanted_t* other,
+ ...);
void tvbparse_hashed_add(tvbparse_wanted_t* w, ...);
* The list of candidates is terminated with a NULL.
*
*/
-tvbparse_wanted_t* tvbparse_set_seq(int id,
+tvbparse_wanted_t* tvbparse_set_seq(const int id,
const void* private_data,
tvbparse_action_t before_cb,
tvbparse_action_t after_cb,
...);
+
/*
* some
*
* a composed element is returned.
*
*/
-tvbparse_wanted_t* tvbparse_some(int id,
- guint min,
- guint max,
+tvbparse_wanted_t* tvbparse_some(const int id,
+ const guint min,
+ const guint max,
const void* private_data,
tvbparse_action_t before_cb,
tvbparse_action_t after_cb,
tvbparse_some(id, 1, G_MAXINT, private_data, before_cb, after_cb, wanted)
-/*
+/*
* handle
*
* this is a pointer to a pointer to a wanted element (that might have not
*
* C strings are matched with tvbparse_quoted(-1,NULL,NULL,NULL,"\"","\\")
*/
-tvbparse_wanted_t* tvbparse_quoted(int id,
+tvbparse_wanted_t* tvbparse_quoted(const int id,
const void* data,
tvbparse_action_t before_cb,
tvbparse_action_t after_cb,
- char quote,
- char escape);
+ const char quote,
+ const char escape);
/*
* a helper callback for quoted strings that will shrink the token to contain
/* initialize the parser (at every packet)
-* tvb: what are we parsing?
-* offset: from where
-* len: for how many bytes
-* private_data: will be passed to the action callbacks
-* ignore: a wanted token type to be ignored (the associated cb WILL be called when it matches)
-*/
+ * tvb: what are we parsing?
+ * offset: from where
+ * len: for how many bytes
+ * private_data: will be passed to the action callbacks
+ * ignore: a wanted token type to be ignored (the associated cb WILL be called when it matches)
+ */
tvbparse_t* tvbparse_init(tvbuff_t* tvb,
- int offset,
+ const int offset,
int len,
void* private_data,
const tvbparse_wanted_t* ignore);
/* reset the parser */
-gboolean tvbparse_reset(tvbparse_t* tt, int offset, int len);
+gboolean tvbparse_reset(tvbparse_t* tt, const int offset, int len);
guint tvbparse_curr_offset(tvbparse_t* tt);
guint tvbparse_len_left(tvbparse_t* tt);
* This will look for the wanted token at the current offset or after any given
* number of ignored tokens returning FALSE if there's no match or TRUE if there
* is a match.
- * The parser will be left in its original state and no callbacks will be called.
+ * The parser will be left in its original state and no callbacks will be called.
*/
gboolean tvbparse_peek(tvbparse_t* tt,
- const tvbparse_wanted_t* wanted);
+ const tvbparse_wanted_t* wanted);
/*
* This will look for the wanted token at the current offset or after any given
* number of ignored tokens returning NULL if there's no match.
* if there is a match it will set the offset of the current parser after
- * the end of the token
+ * the end of the token
*/
tvbparse_elem_t* tvbparse_get(tvbparse_t* tt,
const tvbparse_wanted_t* wanted);
* current offset.
* This function is slow.
*/
-
tvbparse_elem_t* tvbparse_find(tvbparse_t* tt,
const tvbparse_wanted_t* wanted);