ScratchBorrow Class Reference

A scratch borrow whose acquire and release are one call each. More...

#include <scratch.h>

Public Member Functions
	ScratchBorrow (size_t n, size_t align)
	~ScratchBorrow ()
	ScratchBorrow (const ScratchBorrow &)=delete
ScratchBorrow &	operator= (const ScratchBorrow &)=delete
const pc_span &	span () const
	The borrowed region; empty if the arena could not satisfy it.

Detailed Description

A scratch borrow whose acquire and release are one call each.

ScratchScope + pc_scratch_span costs three crossings of this module's boundary: mark, alloc, then release. Mark and alloc always happen together, so one of those is structure rather than work. This does both in the constructor and the release in the destructor - two calls, and the slot is resolved once instead of twice.

The pool's state stays private to the .cpp; that is exactly why these cannot be inlined instead, and why LTO would have been the alternative (it is unavailable here - the ESP32 core does not link with -flto).

Fails closed like every other borrow: an exhausted arena leaves span() empty, so a caller that omits the check writes nothing rather than dereferencing null.

Definition at line 167 of file scratch.h.

Constructor & Destructor Documentation

ScratchBorrow() [1/2]

ScratchBorrow::ScratchBorrow	(	size_t	n,
		size_t	align
	)

Definition at line 118 of file scratch.cpp.

References pc_arena_scratch_alloc_aligned(), pc_arena_scratch_mark(), and pc_span_from().

~ScratchBorrow()

ScratchBorrow::~ScratchBorrow

(

)

Definition at line 128 of file scratch.cpp.

References pc_arena_scratch_release().

ScratchBorrow() [2/2]

ScratchBorrow::ScratchBorrow ( const ScratchBorrow &  )

delete

Member Function Documentation

operator=()

ScratchBorrow & ScratchBorrow::operator= ( const ScratchBorrow &  )

delete

span()

const pc_span & ScratchBorrow::span ( ) const

inline

The borrowed region; empty if the arena could not satisfy it.

Definition at line 176 of file scratch.h.

Referenced by pc_ssh_server_dispatch().

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The documentation for this class was generated from the following files:

• src/server/mmgr/scratch.h
• src/server/mmgr/scratch.cpp