Suggested solution for #30, only update if newer driver (#31)

* Suggested solution for #30, only update if newer driver

* Removed dependency on nvidia-smi, now uses pacman and 'nvidia-utils' as search string

PKGBUILD

@@ -28,7 +28,7 @@ source "$where"/customization.cfg
 
 # Load external configuration file if present. Available variable values will overwrite customization.cfg ones.
 if [ -e "$_EXT_CONFIG_PATH" ]; then
-  source "$_EXT_CONFIG_PATH" && msg2 "External configuration file $_EXT_CONFIG_PATH will be used to override customization.cfg values." && msg2 ""
+  source "$_EXT_CONFIG_PATH" && msg2 "External configuration file '$_EXT_CONFIG_PATH' will be used to override customization.cfg values." && plain ""
 fi
 
 # Auto-add kernel userpatches to source
@@ -126,6 +126,42 @@ if [ -e options ]; then
   source options
 fi
 
+# Check if the version we are going for is newer or not if enabled
+if [[ "$_only_update_if_newer" == "true" ]]; then
+  # Check current version, if possible 
+  if pacman -Qs "nvidia-utils" >/dev/null; then
+    # We have enough packages installed to get the version
+    # returns a string, like "460.39" or "455.45.01"
+    # HACK Checks the first nvidia-utils match, does not catch potential missmatches and other stuff
+    _current_version=$(pacman -Q "nvidia-utils" | grep -oP '\d+(\.\d+)+' | head -n 1)
+    _current_package_example=$(pacman -Q "nvidia-utils" | grep -oP '[a-z]+(\-[a-z]+)+' | head -n 1)
+    msg2 "Found version $_current_version installed (from package '$_current_package_example')"
+
+    ## HACK Stupid string compare
+    ## TODO Ensure that nvidia versions do not differ from this format
+    if [[ $_driver_version > $_current_version ]]; then
+      # We have a newer version to install, do nothing
+      msg2 "Selected version ($_driver_version, $_driver_branch) is newer than installed version, continuing."
+    else
+      # Older version, or at least not newer version
+      msg2 "Selected version ($_driver_version, $_driver_branch) is not newer than installed version, exiting."
+      plain ""
+      if [ -e "$_EXT_CONFIG_PATH" ]; then
+        plain "If this is not intended, have a look at '$_EXT_CONFIG_PATH'"
+      else
+        plain "If this is not intended, have a look at '"$where"/customization.cfg'"
+      fi
+
+      # We shouldn't have done anything yet, so no cleanup needed?
+      exit 0
+    fi
+  else
+    warning "'\$_only_update_if_newer' is enabled, but no installed driver found."
+    warning "Continuing on as if '\$_only_update_if_newer' was not enabled."
+    plain ""
+  fi
+fi
+
 msg2 "Building driver version $_driver_version on branch $_driver_branch."
 
 # Skip header check for dkms-only builds with explicit target kernel version

customization.cfg

@@ -31,6 +31,11 @@ _driver_branch=""
 # Set to "latest" to use the latest driver on the selected branch.
 _driver_version=""
 
+# Only updates if there is a newer version available
+# Semi-hack, compares version-strings as strings, i.e. if "460.39" > "455.45.01" update etc
+# Set to "true" to enable
+_only_update_if_newer=""
+
 # Set to "true" to use DKMS or "false" to use regular modules. You can also use "full" to build both dkms and regular packages (don't use it if you don't know you need it!).
 _dkms=""