#include <cairo.h>
#include <dirent.h>
#include <inttypes.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <primitives/primitives.h>
#include <wlclient/wlclient.h>
#include <wlclient/icon.h>
#include <wlclient/dblbuf.h>
#include <libbase/libbase.h>

Include dependency graph for wlmbattery.c:

Classes
struct	wlm_power_supply

struct	wlm_power_adapter

struct	wlm_battery

struct	callback_arg

Macros
#define	SYSFS_BATTERY_PATH_MAX_LEN 256

#define	VAL_BUF_LEN 64

Enumerations
enum	battery_status { BATTERY_STATUS_UNKNOWN = 0 , BATTERY_STATUS_CHARGING , BATTERY_STATUS_DISCHARGING , BATTERY_STATUS_NOT_CHARGING , BATTERY_STATUS_FULL }

Functions
static struct wlm_power_supply *	wlm_power_supply_create (void)

static void	wlm_power_supply_destroy (struct wlm_power_supply *ps)

static bool	wlm_power_supply_read (struct wlm_power_supply *ps)

static size_t	wlm_power_supply_num_batteries (struct wlm_power_supply *ps)

static struct wlm_battery *	wlm_power_supply_battery (struct wlm_power_supply *ps, size_t index)

static bool	wlm_power_supply_connected (struct wlm_power_supply *ps)

static struct wlm_battery *	wlm_battery_create (const char name_ptr, const char power_supply_dir)

static void	wlm_battery_destroy (bs_dllist_node_t dlnode_ptr, void ud_ptr)

static bool	wlm_battery_read (struct wlm_battery *bat)

static struct wlm_power_adapter *	wlm_power_adapter_create (const char name_ptr, const char power_supply_dir)

static void	wlm_power_adapter_destroy (bs_dllist_node_t dlnode_ptr, void ud_ptr)

static bool	wlm_power_adapter_connected (bs_dllist_node_t node_ptr, void ud_ptr)

static bool	wlm_power_adapter_read (struct wlm_power_adapter *adapter)

static bool	wlm_vread_buffer (char v, size_t v_size, const char fmt_ptr, va_list ap)

static bool	wlm_read_buffer (char v, size_t v_size, const char fmt_ptr,...)

static bool	wlm_read_uint64 (uint64_t u64_ptr, const char fmt_ptr,...)

static enum battery_status	parse_battery_status (const char *status_str)

bool	icon_callback (bs_gfxbuf_t gfxbuf_ptr, void ud_ptr)

void	timer_callback (wlmcl_client_t client_ptr, void ud_ptr)

static void	_handle_configure (void *ud_ptr, uint32_t width, uint32_t height)

int	main (void)

Variables
static wlmcl_client_t *	wlclient_ptr

static wlmcl_dblbuf_t *	dblbuf_ptr

Detailed Description

Displays battery capacity from /sys/class/power_supply in a DockApp.

TODO(kaese.nosp@m.r@gu.nosp@m.bbe.c.nosp@m.h):

Only update when the numbers have actually changed.
Support more than one battery (eg. by clicking through?)
Use graphics for visualization, this initial version is very crude.
Permit dynamic size of the app, currently it's fixed to 64x64.

Copyright: Copyright (c) 2026 Philipp Kaeser (kaese.nosp@m.r@gu.nosp@m.bbe.c.nosp@m.h) Copyright 2026 Google LLC

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

https://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

Macro Definition Documentation

◆ SYSFS_BATTERY_PATH_MAX_LEN

#define SYSFS_BATTERY_PATH_MAX_LEN 256

Sufficient for the typical paths, although there is no strict maximum.

◆ VAL_BUF_LEN

#define VAL_BUF_LEN 64

Small buffer for reading single values (like capacity).

Enumeration Type Documentation

◆ battery_status

enum battery_status

Internal battery status enum.

Function Documentation

◆ _handle_configure()

static void _handle_configure	(	void *	ud_ptr,
		uint32_t	width,
		uint32_t	height
	)

static

Handles configure events.

◆ icon_callback()

bool icon_callback	(	bs_gfxbuf_t *	gfxbuf_ptr,
		void *	ud_ptr
	)

Draws current byttery status into the icon buffer.

Parameters

gfxbuf_ptr
ud_ptr

◆ main()

int main ( void )

Returns: EXIT_SUCCESS on success.

◆ parse_battery_status()

static enum battery_status parse_battery_status ( const char * status_str )

static

Maps standard sysfs status string to internal enum.

Parameters

status_str String literal describing the battery status.

Returns: The corresponding parsed internal enum status.

◆ timer_callback()

void timer_callback	(	wlmcl_client_t *	client_ptr,
		void *	ud_ptr
	)

Called once per second.

◆ wlm_battery_create()

struct wlm_battery * wlm_battery_create	(	const char *	name_ptr,
		const char *	power_supply_dir
	)

static

Creates battery struct spanning the specific name_ptr.

Parameters

name_ptr	Null-terminated property name segment (e.g. "BAT0").
power_supply_dir	The root directory where sysfs devices live.

Returns: Pointer to allocated battery structure, or NULL on error.

◆ wlm_battery_destroy()

void wlm_battery_destroy	(	bs_dllist_node_t *	dlnode_ptr,
		void *	ud_ptr
	)

static

Destroys battery struct.

Parameters

dlnode_ptr
ud_ptr

◆ wlm_battery_read()

bool wlm_battery_read ( struct wlm_battery * bat )

static

Helper to pull all readings into the structural cache representation.

Parameters

bat	Pointer to the target battery object tracking the metric states.

Returns: True on success.

◆ wlm_power_adapter_connected()

bool wlm_power_adapter_connected	(	bs_dllist_node_t *	node_ptr,
		void *	ud_ptr
	)

static

Iterator function to verify whether a power adapter node is connected.

Parameters

node_ptr	The doubly-linked list node embedded in a wlm_power_adapter.
ud_ptr	Ignored user data.

Returns: True if the adapter is online.

◆ wlm_power_adapter_create()

struct wlm_power_adapter * wlm_power_adapter_create	(	const char *	name_ptr,
		const char *	power_supply_dir
	)

static

Creates adapter struct spanning the specific name_ptr.

Parameters

name_ptr	Null-terminated property name segment (e.g. "AC0").
power_supply_dir	The root directory where sysfs devices live.

Returns: Pointer to allocated adapter structure, or NULL on error.

◆ wlm_power_adapter_destroy()

void wlm_power_adapter_destroy	(	bs_dllist_node_t *	dlnode_ptr,
		void *	ud_ptr
	)

static

Destroys power adapter struct.

Parameters

dlnode_ptr	The list node of the power adapter to destroy.
ud_ptr

◆ wlm_power_adapter_read()

bool wlm_power_adapter_read ( struct wlm_power_adapter * adapter )

static

Reads power adapter properties into the structural cache representation.

Parameters

adapter Pointer to the target power adapter object.

Returns: True on success.

◆ wlm_power_supply_battery()

struct wlm_battery * wlm_power_supply_battery	(	struct wlm_power_supply *	ps,
		size_t	index
	)

static

Extract battery handle at specified index linearly.

Parameters

ps	Pointer to the structured system state container.
index	Index integer for node traversal limit bounding.

Returns: Sliced battery memory, NULL if invalid parameter passed.

◆ wlm_power_supply_connected()

bool wlm_power_supply_connected ( struct wlm_power_supply * ps )

static

Indicates if any of the power adapters is online.

Parameters

ps	Pointer to the target power supply.

Returns: True if at least one adapter is connected and online, otherwise false.

◆ wlm_power_supply_create()

struct wlm_power_supply * wlm_power_supply_create ( void )

static

Iterates through /sys/class/power_supply and creates corresponding battery and adapter items.

Returns: Pointer to the power supply, or NULL on error.

◆ wlm_power_supply_destroy()

void wlm_power_supply_destroy ( struct wlm_power_supply * ps )

static

Destroys the power supply container and internal batteries/adapters.

Parameters

ps	Pointer to the target power supply.

◆ wlm_power_supply_num_batteries()

size_t wlm_power_supply_num_batteries ( struct wlm_power_supply * ps )

static

Returns the tracked amount of batteries.

Parameters

ps	Pointer to the target power supply.

Returns: the tracked amount of batteries.

◆ wlm_power_supply_read()

bool wlm_power_supply_read ( struct wlm_power_supply * ps )

static

Reads current state of the power supply (batteries and adapters).

Parameters

ps

Returns: true on success.

◆ wlm_read_buffer()

bool wlm_read_buffer	(	char *	v,
		size_t	v_size,
		const char *	fmt_ptr,
			...
	)

static

Reads content of file named by the formatted path into the buffer.

Parameters

v	Output buffer.
v_size	Length boundary for `v`.
fmt_ptr	Format string for the path.
...	Arguments for the format string.

Returns: True if read safely, otherwise false.

◆ wlm_read_uint64()

bool wlm_read_uint64	(	uint64_t *	u64_ptr,
		const char *	fmt_ptr,
			...
	)

static

Reads content of file named by the formatted path and parses it as uint64.

Parameters

u64_ptr	Output pointer for the parsed integer.
fmt_ptr	Format string for the path.
...	Arguments for the format string.

Returns: True on successful parse, otherwise false.

◆ wlm_vread_buffer()

bool wlm_vread_buffer	(	char *	v,
		size_t	v_size,
		const char *	fmt_ptr,
		va_list	ap
	)

static

Reads content of file named by the formatted path into a buffer.

Parameters

v	Output buffer.
v_size	Length boundary for `v`.
fmt_ptr	Format string for the path.
ap	Variadic arguments list.

Returns: True if read safely, otherwise false.

Variable Documentation

◆ dblbuf_ptr

wlmcl_dblbuf_t* dblbuf_ptr

static

Double buffer pointer.

◆ wlclient_ptr

wlmcl_client_t* wlclient_ptr

static

Wayland client state.

Classes

Macros

Enumerations

Functions

Variables

Detailed Description

Macro Definition Documentation

◆ SYSFS_BATTERY_PATH_MAX_LEN

◆ VAL_BUF_LEN

Enumeration Type Documentation

◆ battery_status

Function Documentation

◆ _handle_configure()

◆ icon_callback()

◆ main()

◆ parse_battery_status()

◆ timer_callback()

◆ wlm_battery_create()

◆ wlm_battery_destroy()

◆ wlm_battery_read()

◆ wlm_power_adapter_connected()

◆ wlm_power_adapter_create()

◆ wlm_power_adapter_destroy()

◆ wlm_power_adapter_read()

◆ wlm_power_supply_battery()

◆ wlm_power_supply_connected()

◆ wlm_power_supply_create()

◆ wlm_power_supply_destroy()

◆ wlm_power_supply_num_batteries()

◆ wlm_power_supply_read()

◆ wlm_read_buffer()

◆ wlm_read_uint64()

◆ wlm_vread_buffer()

Variable Documentation

◆ dblbuf_ptr

◆ wlclient_ptr