zlib.h File Reference

RFC 1950 / 1951 deflate, as SSH negotiates it. More...

#include "protocore_config.h"

Go to the source code of this file.

Classes
struct	SshDeflate
	Streaming server-to-client DEFLATE compressor (one per SSH connection). More...
struct	ZlibNs
	Dispatch table. Addressed by offset, so the layout is asserted below. More...

Macros
#define	SSH_ZLIB_HASH_BITS   13
	Hash-table buckets for the LZ77 3-byte match search (2^bits).
#define	SSH_ZLIB_HASH_SIZE   (1 << SSH_ZLIB_HASH_BITS)
#define	SSH_ZLIB_WORK_SIZE   ((size_t)PROTOCORE_SSH_ZLIB_WINDOW + (size_t)PROTOCORE_SSH_ZLIB_MAX_IN)
	Work buffer capacity the compressor needs: window history + one input payload.

Functions
	PROTOCORE_NS_LAYOUT (ZlibNs, init, packet)
void	protocore_zlib_init (uint8_t *work, SshDeflate *z, uint8_t *win, uint16_t *head, uint16_t *prev, uint16_t *ll_code, uint8_t *ll_len, uint16_t *d_code, uint8_t *d_len)
	Bind caller memory to a compressor and reset it to stream start.
int	protocore_zlib_packet (uint8_t *work, SshDeflate *z, const uint8_t *src, size_t src_len, uint8_t *dst, size_t dst_cap, size_t *out_len)
	Compress one packet payload, continuing the session's zlib stream. .

Variables
PROTOCORE_NS ZlibNs Zlib	PROTOCORE_UNUSED = {.init = protocore_zlib_init, .packet = protocore_zlib_packet}
	Module namespace.

Detailed Description

RFC 1950 / 1951 deflate, as SSH negotiates it.

work is bytes the CALLER holds. This module reads none of them: it carries nothing between calls, so there is no state to keep and nothing to wipe. The parameter is there so a caller drives every namespace the same way.

Definition in file zlib.h.

Macro Definition Documentation

SSH_ZLIB_HASH_BITS

#define SSH_ZLIB_HASH_BITS   13

Hash-table buckets for the LZ77 3-byte match search (2^bits).

Definition at line 25 of file zlib.h.

SSH_ZLIB_HASH_SIZE

#define SSH_ZLIB_HASH_SIZE   (1 << SSH_ZLIB_HASH_BITS)

Definition at line 26 of file zlib.h.

SSH_ZLIB_WORK_SIZE

#define SSH_ZLIB_WORK_SIZE   ((size_t)PROTOCORE_SSH_ZLIB_WINDOW + (size_t)PROTOCORE_SSH_ZLIB_MAX_IN)

Work buffer capacity the compressor needs: window history + one input payload.

Definition at line 29 of file zlib.h.

Function Documentation

PROTOCORE_NS_LAYOUT()

PROTOCORE_NS_LAYOUT	(	ZlibNs	,
		init	,
		packet
	)

protocore_zlib_init()

void protocore_zlib_init	(	uint8_t *	work,
		SshDeflate *	z,
		uint8_t *	win,
		uint16_t *	head,
		uint16_t *	prev,
		uint16_t *	ll_code,
		uint8_t *	ll_len,
		uint16_t *	d_code,
		uint8_t *	d_len
	)

Bind caller memory to a compressor and reset it to stream start.

Parameters

work	PROTOCORE_ZLIB_BORROW bytes the caller took. Not held past the call.
z	the compressor to initialize
win	history+input buffer, >= SSH_ZLIB_WORK_SIZE bytes
head	hash heads, SSH_ZLIB_HASH_SIZE uint16 entries
prev	hash chain, SSH_ZLIB_WORK_SIZE uint16 entries
ll_code	Ll code
ll_len	Ll len
d_code	D code
d_len	D len

protocore_zlib_packet()

int protocore_zlib_packet	(	uint8_t *	work,
		SshDeflate *	z,
		const uint8_t *	src,
		size_t	src_len,
		uint8_t *	dst,
		size_t	dst_cap,
		size_t *	out_len
	)

Compress one packet payload, continuing the session's zlib stream. .

Parameters

work	PROTOCORE_ZLIB_BORROW bytes the caller took. Not held past the call.
z	the compressor
src	Src
src_len	Src len
dst	Dst
dst_cap	Dst cap
out_len	set to the compressed length on success

Returns

The int.

Variable Documentation

PROTOCORE_UNUSED

PROTOCORE_NS ZlibNs Zlib PROTOCORE_UNUSED = {.init = protocore_zlib_init, .packet = protocore_zlib_packet}

Module namespace.

Definition at line 100 of file zlib.h.