m_config: store file local backup options differently

File local options need to backup the global option value while a file
is played. Instead of keeping a pointer in m_config_option for the
backup value, put it into a separate list. This reduces per-option
overhead for a rarely used obscure feature. (This implementation would
have been a bit dumb in pre-mpv m_config, because there local options
were the default, and _all_ options were backed up when starting
playback of a file. This is not the case anymore, and normally only
a very small number of options are backed up by default.)

1 files changed, 2 insertions, 2 deletions

diff --git a/core/m_config.h b/core/m_config.h
index c48a4f1281..1ee7ecf1c0 100644
--- a/core/m_config.h
+++ b/core/m_config.h
@@ -44,8 +44,6 @@ struct m_config_option {
     const struct m_option *opt;
     // Raw value of the option.
     void *data;
-    // Raw value of the backup of the global value (or NULL).
-    void *global_backup;
     // If this is a suboption, the option that contains this option.
     struct m_config_option *parent;
     // If this option aliases another, more important option. The alias_owner
@@ -70,6 +68,8 @@ typedef struct m_config {
     // Depth when recursively including profiles.
     int profile_depth;
 
+    struct m_opt_backup *backup_opts;
+
     bool use_profiles;
     int (*includefunc)(struct m_config *conf, char *filename);