App cache

Tracks the applications whose binaries are stored on the watch. More...

Functions
void	app_cache_init (void)
	Initialize the app cache.
status_t	app_cache_add_entry (AppInstallId app_id, uint32_t total_size)
	Add an entry for a newly installed app.
status_t	app_cache_remove_entry (AppInstallId app_id)
	Remove an app's entry and delete its binaries.
bool	app_cache_entry_exists (AppInstallId app_id)
	Check whether an app has an entry in the cache.
status_t	app_cache_app_launched (AppInstallId app_id)
	Record a launch of an app.
status_t	app_cache_free_up_space (uint32_t bytes_needed)
	Evict apps until at least bytes_needed bytes of binaries are freed.
void	app_cache_flush (void)
	Clear the whole cache and delete all cached app binaries.

Detailed Description

Tracks the applications whose binaries are stored on the watch.

Each entry records an app's size, install date, last launch and launch count, persisted in a settings file. When storage runs low, the entries with the lowest priority (least recently installed or launched) are evicted and their binaries deleted; the default watchface and worker and the quick launch apps are only evicted as a last resort. Removing an entry deletes the app's binaries and emits a PEBBLE_APP_CACHE_EVENT.

Function Documentation

app_cache_add_entry()

status_t app_cache_add_entry	(	AppInstallId	app_id,
		uint32_t	total_size
	)

Add an entry for a newly installed app.

Schedules an eviction on KernelBackground if free space is now too low.

Parameters

app_id	App to add.
total_size	Size of the app's binaries, in bytes.

Returns

S_SUCCESS or an error from the settings file.

app_cache_app_launched()

status_t app_cache_app_launched

(

AppInstallId

app_id

)

Record a launch of an app.

Updates the last launch time and launch count. If the app has no entry, its binaries are deleted.

Parameters

app_id

Launched app.

Returns

S_SUCCESS or an error from the settings file.

app_cache_entry_exists()

bool app_cache_entry_exists

(

AppInstallId

app_id

)

Check whether an app has an entry in the cache.

An entry whose binaries are missing from storage is removed.

Parameters

app_id

App to look up.

Returns

true if the entry exists and the app's binaries are stored.

app_cache_flush()

void app_cache_flush

(

void

)

Clear the whole cache and delete all cached app binaries.

Must be called from KernelBackground.

app_cache_free_up_space()

status_t app_cache_free_up_space

(

uint32_t

bytes_needed

)

Evict apps until at least bytes_needed bytes of binaries are freed.

Parameters

bytes_needed

Number of bytes to free.

Return values

S_SUCCESS	Success.
E_INVALID_ARGUMENT	bytes_needed is 0.

Returns

Other errors come from the settings file.

app_cache_init()

void app_cache_init

(

void

)

Initialize the app cache.

Deletes leftover app binaries when no cache file exists and purges orphaned resource files.

app_cache_remove_entry()

status_t app_cache_remove_entry

(

AppInstallId

app_id

)

Remove an app's entry and delete its binaries.

Parameters

app_id

App to remove.

Returns

S_SUCCESS or an error from the settings file.