dbuffer.c File Reference

A dbuffer is a dynamically sized buffer that stores arbitrary bytes in a queue. It does not provide random access; characters may be inserted only at the end and removed only from the beginning. More...

#include "common.h"
#include <SDL_thread.h>

Include dependency graph for dbuffer.c:

Go to the source code of this file.

Data Structures
struct	dbuffer_element
Defines
#define	DBUFFER_ELEMENT_SIZE 4000
#define	DBUFFER_ELEMENTS_FREE_THRESHOLD 1000
#define	DBUFFER_FREE_THRESHOLD 1000
Functions
static struct dbuffer_element *	allocate_element (void)
static void	free_element (struct dbuffer_element *e)
struct dbuffer *	new_dbuffer (void)
	Allocate a dbuffer.
void	free_dbuffer (struct dbuffer *buf)
	Deallocate a dbuffer.
static void	dbuffer_grow (struct dbuffer *buf, size_t len)
	This grows the buffer to provide at least enough space for the.
struct dbuffer *	dbuffer_merge (struct dbuffer old, struct dbuffer old2)
	Merges two dbuffers.
struct dbuffer *	dbuffer_prepend (struct dbuffer old, const char data, size_t len)
	Allocate a dbuffer and prepend the given data to it.
void	dbuffer_add (struct dbuffer buf, const char data, size_t len)
	Append data to a dbuffer.
size_t	dbuffer_get (const struct dbuffer buf, char data, size_t len)
	Read data from a dbuffer.
size_t	dbuffer_get_at (const struct dbuffer buf, size_t offset, char data, size_t len)
	Read data from a dbuffer.
struct dbuffer *	dbuffer_dup (struct dbuffer *old)
	Allocate a dbuffer.
size_t	dbuffer_remove (struct dbuffer *buf, size_t len)
	Deletes data from a dbuffer.
size_t	dbuffer_extract (struct dbuffer buf, char data, size_t len)
	Read and delete data from a dbuffer.
void	dbuffer_init (void)
void	dbuffer_shutdown (void)
Variables
static int	free_elements = 0
static int	allocated_elements = 0
static struct dbuffer_element *	free_element_list = NULL
static int	free_dbuffers = 0
static int	allocated_dbuffers = 0
static struct dbuffer *	free_dbuffer_list = NULL
static SDL_mutex *	dbuf_lock

Detailed Description

A dbuffer is a dynamically sized buffer that stores arbitrary bytes in a queue. It does not provide random access; characters may be inserted only at the end and removed only from the beginning.

Definition in file dbuffer.c.

Define Documentation

#define DBUFFER_ELEMENT_SIZE 4000

Definition at line 30 of file dbuffer.c.

Referenced by allocate_element(), dbuffer_extract(), dbuffer_grow(), dbuffer_remove(), and new_dbuffer().

#define DBUFFER_ELEMENTS_FREE_THRESHOLD 1000

Definition at line 36 of file dbuffer.c.

Referenced by free_element().

#define DBUFFER_FREE_THRESHOLD 1000

Definition at line 37 of file dbuffer.c.

Referenced by free_dbuffer().

Function Documentation

static struct dbuffer_element* allocate_element ( void ) [static, read]

See also:: free_element

Definition at line 57 of file dbuffer.c.

References allocated_elements, com_genericPool, dbuf_lock, DBUFFER_ELEMENT_SIZE, free_elements, dbuffer_element::len, Mem_PoolAlloc, dbuffer_element::next, and dbuffer_element::space.

Referenced by dbuffer_grow(), and new_dbuffer().

void dbuffer_add	(	struct dbuffer *	buf,
		const char *	data,
		size_t	len
	)

Append data to a dbuffer.

Parameters:

`[in,out]`	buf	the target buffer
`[in]`	data	pointer to the start of the bytes to add
`[in]`	len	number of bytes to add Adds the given sequence of bytes to the end of the buffer.

Definition at line 263 of file dbuffer.c.

References dbuffer_element::data, dbuffer_grow(), dbuffer::end, dbuffer::len, dbuffer_element::len, dbuffer_element::next, dbuffer_element::space, dbuffer::space, and dbuffer::tail.

Referenced by CL_ForwardToServer_f(), Cmd_ForwardToServer(), dbuffer_dup(), dbuffer_merge(), dbuffer_prepend(), NET_ReadMsg(), NET_StreamEnqueue(), NET_VPrintf(), NET_Wait(), NET_WriteByte(), NET_WriteChar(), NET_WriteLong(), NET_WriteRawString(), NET_WriteShort(), and NET_WriteString().

struct dbuffer* dbuffer_dup ( struct dbuffer * old ) [read]

Allocate a dbuffer.

Parameters:

[in] old the source buffer

Returns:: the newly allocated buffer Allocates a new dbuffer and initialises it to contain a copy of the data in old

Definition at line 397 of file dbuffer.c.

References dbuffer_element::data, dbuffer_add(), dbuffer::head, dbuffer_element::len, new_dbuffer(), dbuffer_element::next, and dbuffer::start.

Referenced by CL_ParseEvent().

size_t dbuffer_extract	(	struct dbuffer *	buf,
		char *	data,
		size_t	len
	)

Read and delete data from a dbuffer.

Parameters:

`[in,out]`	buf	the source buffer
`[out]`	data	pointer to where the data should be copied
`[in]`	len	maximum number of bytes to copy

Returns:: number of bytes copied

: Copies up to len bytes into data, and removes them from the dbuffer

: If the buffer does not contain at least len bytes, then as many bytes as are present will be copied.

: However many bytes are copied, exactly that many will be removed from the start of the dbuffer.

Definition at line 471 of file dbuffer.c.

References dbuffer_element::data, DBUFFER_ELEMENT_SIZE, dbuffer::end, free_element(), dbuffer::head, dbuffer_element::len, dbuffer::len, dbuffer_element::next, dbuffer::space, and dbuffer::start.

Referenced by NET_ReadByte(), NET_ReadChar(), NET_ReadLong(), NET_ReadShort(), NET_StreamDequeue(), and NET_WriteMsg().

size_t dbuffer_get	(	const struct dbuffer *	buf,
		char *	data,
		size_t	len
	)

Read data from a dbuffer.

Parameters:

`[in]`	buf	the source buffer
`[out]`	data	pointer to where the data should be copied
`[in]`	len	maximum number of bytes to copy

Returns:: number of bytes copied

: Copies up to len bytes into data

: If the buffer does not contain at least len bytes, then as many bytes as are present will be copied.

Definition at line 310 of file dbuffer.c.

References dbuffer_element::data, dbuffer::head, dbuffer_element::len, dbuffer_element::next, and dbuffer::start.

Referenced by NET_PeekShort(), NET_StreamPeek(), and NET_Wait().

size_t dbuffer_get_at	(	const struct dbuffer *	buf,
		size_t	offset,
		char *	data,
		size_t	len
	)

Read data from a dbuffer.

Parameters:

`[in]`	buf	the source buffer
`[in]`	offset	the offset in the source buffer where data should be copied from
`[out]`	data	pointer to where the data should be copied
`[in]`	len	maximum number of bytes to copy

Returns:: number of bytes copied

: Copies up to len bytes into data

: If the buffer does not contain at least len bytes after offset, then as many bytes as are present will be copied.

Definition at line 350 of file dbuffer.c.

References dbuffer_element::data, dbuffer::head, dbuffer_element::len, dbuffer_element::next, and dbuffer::start.

Referenced by NET_WriteConstMsg().

static void dbuffer_grow	(	struct dbuffer *	buf,
		size_t	len
	)			`[inline, static]`

This grows the buffer to provide at least enough space for the.

Parameters:

`[in,out]`	buf	the target buffer
`[in]`	len	number of bytes to add given length, plus one character (see the comments in dbuffer_add() for the explanation of that extra character).

Definition at line 181 of file dbuffer.c.

References allocate_element(), DBUFFER_ELEMENT_SIZE, dbuffer_element::next, dbuffer::space, and dbuffer::tail.

Referenced by dbuffer_add().

void dbuffer_init ( void )

Definition at line 503 of file dbuffer.c.

References dbuf_lock.

Referenced by NET_Init().