config/output: Search for output config fallbacks

The original sway output config implementation enabled one output at a
time, testing modes, render formats and VRR support as it went along.
While this sort of fallback is easy to do, it has the downside of not
considering the effect of neighbor outputs on the configuration
viability.

With backend-wide commits, we can now better consider the effect of
neighbor outputs, but to handle the fact that we commit all outputs at
once we need to perform a more elaborate search of viable
configurations.

Implement a recursive configuration search for when the primary
configuration failed to apply.

1 files changed, 4 insertions, 1 deletions

diff --git a/include/sway/config.h b/include/sway/config.h
index 0be1cd22..5ccc3e77 100644
--- a/include/sway/config.h
+++ b/include/sway/config.h
@@ -689,10 +689,13 @@ const char *sway_output_scale_filter_to_string(enum scale_filter_mode scale_filt
 struct output_config *new_output_config(const char *name);
 
 bool apply_output_configs(struct matched_output_config *configs,
-                size_t configs_len, bool test_only);
+                size_t configs_len, bool test_only, bool degrade_to_off);
 
 void apply_all_output_configs(void);
 
+void sort_output_configs_by_priority(struct matched_output_config *configs,
+                size_t configs_len);
+
 /**
  * store_output_config stores a new output config. An output may be matched by
  * three different config types, in order of precedence: Identifier, name and