bytes.h File Reference

Cursor byte-copy helpers shared by the frame codecs. More...

#include "common/bytes/span/span.h"
#include "common/platform/sys/syscall.h"

Go to the source code of this file.

Functions
static int	bytes_put (wired_mspan buf, usz *off, wired_span src)
	Append src into buf at *off.
static int	bytes_take (wired_span buf, usz *off, wired_mspan dst)
	Copy dst.n bytes into dst from *off (buf total).
static void *	bytes_memcpy (void *dst, const void *src, usz n)
	Freestanding byte copy.
static void *	bytes_move_down (void *dst, const void *src, usz n)
	Byte copy toward lower addresses: dst may overlap src as long as dst <= src (a forward copy then never reads a byte it already overwrote), e.g.
static void *	bytes_memset (void *dst, int c, usz n)
	Freestanding byte fill.
static usz	wired_cstr_len (const char *s)
	Freestanding NUL-terminated string length.
static u8	ascii_lower (u8 c)
	ASCII lowercase of one octet (A-Z -> a-z, everything else unchanged).
static int	ascii_dns_eq (wired_span a, wired_span b)
	RFC 6125 6.4.1: ASCII case-insensitive equality of two DNS-name-shaped byte spans (host names, SNI values).

Detailed Description

Cursor byte-copy helpers shared by the frame codecs.

Inline so multiple codec translation units can use them without redefining a static helper.

Function Documentation

ascii_dns_eq()

int ascii_dns_eq ( wired_span a, wired_span b )

inlinestatic

RFC 6125 6.4.1: ASCII case-insensitive equality of two DNS-name-shaped byte spans (host names, SNI values).

Non-ASCII bytes compare bytewise (no folding applied outside A-Z).

Parameters

a	first span
b	second span

Returns

1 if equal length and equal after ASCII case-folding, 0 otherwise.

ascii_lower()

u8 ascii_lower ( u8 c )

inlinestatic

ASCII lowercase of one octet (A-Z -> a-z, everything else unchanged).

Parameters

c	input octet

Returns

lowercased octet

bytes_memcpy()

void * bytes_memcpy ( void * dst, const void * src, usz n )

inlinestatic

Freestanding byte copy.

Even under -ffreestanding -fno-builtin the compiler still emits memcpy/memset calls for struct and array copies/zeroing (e.g. modexp.c, ed25519_sign.c, respond.c), and with -nostdlib no libc supplies them. The SDK owns these primitives; each freestanding binary's mandatory libc-named memcpy/memset shim (the symbol names the compiler hard-codes) just forwards to these.

Parameters

dst	destination buffer (must not overlap src)
src	source buffer
n	number of bytes to copy

Returns

dst

bytes_memset()

void * bytes_memset ( void * dst, int c, usz n )

inlinestatic

Freestanding byte fill.

See bytes_memcpy() for why the SDK owns this.

Parameters

dst	buffer to fill
c	fill byte (truncated to u8)
n	number of bytes to fill

Returns

dst

bytes_move_down()

void * bytes_move_down ( void * dst, const void * src, usz n )

inlinestatic

Byte copy toward lower addresses: dst may overlap src as long as dst <= src (a forward copy then never reads a byte it already overwrote), e.g.

sliding a buffer's tail down to its front.

The loop is the same as bytes_memcpy's today, but only this contract promises forward order: bytes_memcpy stays free to copy in any order.

Parameters

dst	destination, at or below src
src	source buffer
n	number of bytes to copy

Returns

dst

bytes_put()

int bytes_put ( wired_mspan buf, usz * off, wired_span src )

inlinestatic

Append src into buf at *off.

Both buf and src are borrowed views: no ownership transfers and nothing is copied into new storage, so buf and src must stay alive (and unmoved) only for the duration of this call.

Parameters

buf	destination buffer (its .n is the total capacity)
off	write cursor into buf; advanced by src.n on success
src	bytes to append

Returns

1 ok, 0 if no room.

bytes_take()

int bytes_take ( wired_span buf, usz * off, wired_mspan dst )

inlinestatic

Copy dst.n bytes into dst from *off (buf total).

Both buf and dst are borrowed views: no ownership transfers, and each must stay alive (and unmoved) only for the duration of this call.

Parameters

buf	source buffer to read from
off	read cursor into buf; advanced by dst.n on success
dst	destination; exactly dst.n bytes are copied

Returns

1 ok, 0 if truncated.

wired_cstr_len()

usz wired_cstr_len ( const char * s )

inlinestatic

Freestanding NUL-terminated string length.

src/ has no libc strlen.

Parameters

s	NUL-terminated string

Returns

number of bytes before the terminating NUL