Enable fsync & esync by default

Also support `PROTON_NO_FSYNC` and `PROTON_NO_ESYNC` environment
variables as used by Proton.

CHANGELOG.md

@@ -6,6 +6,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 
 ## [Unreleased]
+### Added
+ - fsync/esync is enabled by default
+ - `PROTON_NO_FSYNC` and `PROTON_NO_ESYNC` environment variables are supported
+
 ### Fixed
  - Fix Wine crash when the Steam application and Protontricks are running at the same time
  - Fix Steam installation detection when both non-Flatpak and Flatpak versions of Steam are installed for the same user

src/protontricks/data/scripts/wine_launch.sh

@@ -50,6 +50,19 @@ if [[ -z "$PROTONTRICKS_FIRST_START" ]]; then
         done
     fi
 
+    # Enable fsync & esync by default
+    if [[ -z "$WINEFSYNC" ]]; then
+        if [[ -z "$PROTON_NO_FSYNC" || "$PROTON_NO_FSYNC" = "0" ]]; then
+            export WINEFSYNC=1
+        fi
+    fi
+
+    if [[ -z "$WINEESYNC" ]]; then
+        if [[ -z "$PROTON_NO_ESYNC" || "$PROTON_NO_ESYNC" = "0" ]]; then
+            export WINEESYNC=1
+        fi
+    fi
+
     export PROTONTRICKS_FIRST_START=1
 fi