db: the database access layer.

Functions
p_db *	p_db_open (char *db_id)
	Initializes a connection to a database.
p_db *	p_db_open_paths (char *db_id, char *searchpaths)
	same as p_db_open but plugin searchpaths are configurable.
void	p_db_close (p_db *db)
	Closes a connection to a database.
p_query *	p_db_query (p_db *db, time_t start, time_t stop)
	Query data from the database.
p_query *	p_db_query_filtered (p_db *db, int filter, time_t start, time_t stop)
	Query filtered data from the database.
p_packet *	p_db_fetch (p_query *q, time_t *time)
	Fetch the next packet from the resultset.
int	p_db_add (p_db *db, struct p_packet *p, time_t timestamp)
	Add a packet to the database.
void	p_db_finalize (p_query *q)
	Finalize a query.

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Function Documentation

int p_db_add	(	p_db *	db,
		struct p_packet *	p,
		time_t	timestamp
	)

Add a packet to the database.

Adds a new libparticle packet to the database. If necessary a new table will be created.

Parameters:

	db	a valid database handle
	p	a pointer to a libparticle packet
	timestamp	the timestamp of the packet in unixtime

Returns:

0 on success -1 on failure

void p_db_close

(

p_db *

db

)

Closes a connection to a database.

Closes a connection to a database and frees allocated memory. Failure to call p_db_close will result in memory leaks

Parameters:

db

a valid p_db Object

struct p_packet* p_db_fetch	(	p_query *	q,
		time_t *	time
	)

Fetch the next packet from the resultset.

Fetches the next packet from the resultset until all data is fetched or an error is encountered and NULL is returned.

Parameters:

	q	a valid query-handle
	time	a pointer to an int for storage of the packets timestamp ( can be NULL )

Returns:

a valid p_packet or NULL

void p_db_finalize

(

p_query *

q

)

Finalize a query.

Finalizes a query and frees allocated memory Failure to call p_db_finalize will result in memory leaks

Parameters:

q

a valid query-handle

p_db* p_db_open

(

char *

db_id

)

Initializes a connection to a database.

Initializes a connection to a database. Takes a string formatted name_of_the_backend://backend-specific e.g.

 p_db_open("mysql5://packetlog:packetlog@teco142pc.edu:3306/packetlog");

First it will look for a library particledb_name_of_the_backend( here mysql5 ) and load this library ( if it exists). After that the library is used to open a connection to the specified database It is important that the specified user has sufficient access rights for the intended operation ( query or write ).

Parameters:

db_id

location of the database

Returns:

a valid p_db or NULL

p_db* p_db_open_paths	(	char *	db_id,
		char *	searchpaths
	)

same as p_db_open but plugin searchpaths are configurable.

On win32 platform the / path seperator will be replaced with the \ automatically.

On posix platform the \ path seperator will be replaced with the / automatically.

If you like the system dynamic linker search paths included, specify the special SYSTEM searchpath. "SYSTEM;lib" which will search in the system search paths and the ones supplied.*

Parameters:

	db_id	location of the database
	searchpaths	a colon-seperated list of plugin searchpaths, for example; "/lib/;/usr/lib/;plugins/;particle"

Returns:

a valid p_db or NULL

p_query* p_db_query	(	p_db *	db,
		time_t	start,
		time_t	stop
	)

Query data from the database.

Queries data from the database. After querying the data it can be read using p_db_fetch. Example:

 p_db_query(db,10,20,0);

Parameters:

	db	a valid database handle
	start	Start of the data as Unix-Timestamp (if later than stop, order of packets is reversed)
	stop	End of the data as Unix-Timestamp

Returns:

a valid p_query handle on success or NULL

p_query* p_db_query_filtered	(	p_db *	db,
		int	filter,
		time_t	start,
		time_t	stop
	)

Query filtered data from the database.

Queries filtered data from the database using a libparticle-filter First build a filter using p_filter_create,p_filter_add and p_filter_add_str then call p_db_query_filtered using the received handle

Parameters:

	filter	a handle to a libparticle filter
	db	see p_db_query
	start	see p_db_query
	stop	see p_db_query

See also:

p_db_query, p_filter_create, p_filter_add

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