esphome::logger::TaskLogBufferHost Class Reference

Lock-free task log buffer for host platform. More...

#include <task_log_buffer_host.h>

Data Structures
struct	LogMessage

Public Member Functions
	TaskLogBufferHost (size_t slot_count)
	Constructor that takes the number of message slots.
	~TaskLogBufferHost ()
bool	get_message_main_loop (LogMessage **message)
void	release_message_main_loop ()
bool	send_message_thread_safe (uint8_t level, const char *tag, uint16_t line, const char *format, va_list args)
bool HOT	has_messages () const
size_t	size () const

Static Public Attributes
static constexpr size_t	DEFAULT_SLOT_COUNT = 64

Detailed Description

Lock-free task log buffer for host platform.

Threading Model: Multi-Producer Single-Consumer (MPSC)

• Multiple threads can safely call send_message_thread_safe() concurrently

• Only the main loop thread calls get_message_main_loop() and release_message_main_loop()

  Producers (multiple threads) Consumer (main loop only) │ │ ▼ ▼ acquire_write_slot_() get_message_main_loop() CAS on reserve_index_ read write_index_ │ check ready flag ▼ │ write to slot (exclusive) ▼ │ read slot data ▼ │ commit_write_slot_() ▼ set ready=true release_message_main_loop() advance write_index_ set ready=false advance read_index_

This implements a lock-free ring buffer for log messages on the host platform. It uses atomic compare-and-swap (CAS) operations for thread-safe slot reservation without requiring mutexes in the hot path.

Design:

• Fixed number of pre-allocated message slots to avoid dynamic allocation
• Each slot contains a header and fixed-size text buffer
• Atomic CAS for slot reservation allows multiple producers without locks
• Single consumer (main loop) processes messages in order

Definition at line 51 of file task_log_buffer_host.h.

Constructor & Destructor Documentation

TaskLogBufferHost()

esphome::logger::TaskLogBufferHost::TaskLogBufferHost ( size_t slot_count )

explicit

Constructor that takes the number of message slots.

Definition at line 13 of file task_log_buffer_host.cpp.

~TaskLogBufferHost()

esphome::logger::TaskLogBufferHost::~TaskLogBufferHost

(

)

Definition at line 18 of file task_log_buffer_host.cpp.

Member Function Documentation

get_message_main_loop()

bool esphome::logger::TaskLogBufferHost::get_message_main_loop

(

LogMessage **

message

)

Definition at line 120 of file task_log_buffer_host.cpp.

has_messages()

bool HOT esphome::logger::TaskLogBufferHost::has_messages ( ) const

inline

Definition at line 92 of file task_log_buffer_host.h.

release_message_main_loop()

void esphome::logger::TaskLogBufferHost::release_message_main_loop

(

)

Definition at line 143 of file task_log_buffer_host.cpp.

send_message_thread_safe()

bool esphome::logger::TaskLogBufferHost::send_message_thread_safe	(	uint8_t	level,
		const char *	tag,
		uint16_t	line,
		const char *	format,
		va_list	args )

Definition at line 73 of file task_log_buffer_host.cpp.

size()

size_t esphome::logger::TaskLogBufferHost::size ( ) const

inline

Definition at line 97 of file task_log_buffer_host.h.

Field Documentation

DEFAULT_SLOT_COUNT

size_t esphome::logger::TaskLogBufferHost::DEFAULT_SLOT_COUNT = 64

staticconstexpr

Definition at line 54 of file task_log_buffer_host.h.

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

• esphome/components/logger/task_log_buffer_host.h
• esphome/components/logger/task_log_buffer_host.cpp