weston-log: replace weston_log_ctx_compositor_destroy() by weston_log_ctx_destroy()

The function weston_log_ctx_compositor_destroy(), which destroys struct
weston_log_context, takes weston_compositor as argument. We may have a
weston_log_context unlinked from a weston_compositor and currently there
is no way to destroy it.

Add function weston_log_ctx_destroy(), what makes the destruction of
weston_log_context independent of weston_compositor.

With this change, one could destroy a weston_compositor and keep the
related weston_log_context (since now weston_log_context can be destroyed
without the need of a weston_compositor). But if weston_compositor gets
destroyed it's also necessary to destroy weston_log_context::global,
as the debug protocol depends on the compositor. So a listener has been
added to the destroy signal of weston_compositor.

Signed-off-by: Leandro Ribeiro <leandrohr@riseup.net>
This commit is contained in:
Leandro Ribeiro 2020-01-24 01:12:59 -03:00
parent 4f13595aa7
commit 4ec38d18b3
4 changed files with 44 additions and 10 deletions

View File

@ -3381,8 +3381,8 @@ out:
weston_log_scope_destroy(log_scope);
log_scope = NULL;
weston_log_ctx_compositor_destroy(wet.compositor);
weston_compositor_destroy(wet.compositor);
weston_log_ctx_destroy(log_ctx);
weston_log_subscriber_destroy_log(logger);
weston_log_subscriber_destroy_flight_rec(flight_rec);

View File

@ -21,7 +21,7 @@ take place much earlier without the need of a compositor instance.
Instantiation of the :type:`weston_log_context` object takes place using
:func:`weston_log_ctx_create()` and clean-up/destroy with
:func:`weston_log_ctx_compositor_destroy()`.
:func:`weston_log_ctx_destroy()` or :func:`weston_log_ctx_compositor_destroy()`.
Log scopes
----------

View File

@ -2045,7 +2045,7 @@ struct weston_log_context *
weston_log_ctx_create(void);
void
weston_log_ctx_compositor_destroy(struct weston_compositor *compositor);
weston_log_ctx_destroy(struct weston_log_context *log_ctx);
int
weston_compositor_enable_content_protection(struct weston_compositor *compositor);

View File

@ -66,6 +66,7 @@
*/
struct weston_log_context {
struct wl_global *global;
struct wl_listener compositor_destroy_listener;
struct wl_list scope_list; /**< weston_log_scope::compositor_link */
struct wl_list pending_subscription_list; /**< weston_log_subscription::source_link */
};
@ -398,6 +399,22 @@ weston_debug_protocol_advertise_scopes(struct weston_log_context *log_ctx,
weston_debug_v1_send_available(res, scope->name, scope->desc);
}
/** Disable debug-protocol
*
* @param log_ctx The log context where the debug-protocol is linked
*
* @ingroup internal-log
*/
static void
weston_log_ctx_disable_debug_protocol(struct weston_log_context *log_ctx)
{
if (!log_ctx->global)
return;
wl_global_destroy(log_ctx->global);
log_ctx->global = NULL;
}
/** Creates weston_log_context structure
*
* \return NULL in case of failure, or a weston_log_context object in case of
@ -418,27 +435,29 @@ weston_log_ctx_create(void)
wl_list_init(&log_ctx->scope_list);
wl_list_init(&log_ctx->pending_subscription_list);
wl_list_init(&log_ctx->compositor_destroy_listener.link);
return log_ctx;
}
/** Destroy weston_log_context structure
*
* \param compositor The libweston compositor whose weston-debug to tear down.
* \param log_ctx The log context to destroy.
*
* Clears weston_compositor::weston_log_ctx.
* @ingroup log
*
*/
WL_EXPORT void
weston_log_ctx_compositor_destroy(struct weston_compositor *compositor)
weston_log_ctx_destroy(struct weston_log_context *log_ctx)
{
struct weston_log_context *log_ctx = compositor->weston_log_ctx;
struct weston_log_scope *scope;
struct weston_log_subscription *pending_sub, *pending_sub_tmp;
if (log_ctx->global)
wl_global_destroy(log_ctx->global);
/* We can't destroy the log context if there's still a compositor
* that depends on it. This is an user error */
assert(wl_list_empty(&log_ctx->compositor_destroy_listener.link));
weston_log_ctx_disable_debug_protocol(log_ctx);
wl_list_for_each(scope, &log_ctx->scope_list, compositor_link)
fprintf(stderr, "Internal warning: debug scope '%s' has not been destroyed.\n",
@ -456,8 +475,20 @@ weston_log_ctx_compositor_destroy(struct weston_compositor *compositor)
/* pending_subscription_list should be empty at this point */
free(log_ctx);
}
compositor->weston_log_ctx = NULL;
static void
compositor_destroy_listener(struct wl_listener *listener, void *data)
{
struct weston_log_context *log_ctx =
wl_container_of(listener, log_ctx, compositor_destroy_listener);
/* We have to keep this list initalized as weston_log_ctx_destroy() has
* to check if there's any compositor destroy listener registered */
wl_list_remove(&log_ctx->compositor_destroy_listener.link);
wl_list_init(&log_ctx->compositor_destroy_listener.link);
weston_log_ctx_disable_debug_protocol(log_ctx);
}
/** Enable weston-debug protocol extension
@ -493,6 +524,9 @@ weston_compositor_enable_debug_protocol(struct weston_compositor *compositor)
if (!log_ctx->global)
return;
log_ctx->compositor_destroy_listener.notify = compositor_destroy_listener;
wl_signal_add(&compositor->destroy_signal, &log_ctx->compositor_destroy_listener);
fprintf(stderr, "WARNING: debug protocol has been enabled. "
"This is a potential denial-of-service attack vector and "
"information leak.\n");