start: refactor code into functions

utils/bin/start

@@ -5,6 +5,38 @@ usage () {
   echo "   -h   show help and exit"
 }
 
+require() {
+  if ! command -v "$@" >/dev/null 2>&1; then
+    >&2 echo "ERROR: required command not found: $1"
+    exit 1
+  fi
+}
+
+start_with_wsl_agent() {
+  if [ "$#" -gt 0 ]; then
+    SHLVL=0 exec ssh-agent "$SHELL" -c "$@"
+  else
+    SHLVL=0 exec ssh-agent "$SHELL"
+  fi
+}
+
+start_with_windows_agent() {
+  require socat
+  require npiperelay
+
+  # Forward SSH Agent requests from withitn WSL to OpenSSH for Windows, based on:
+  # https://stuartleeks.com/posts/wsl-ssh-key-forward-to-windows/
+  export SSH_AUTH_SOCK=$HOME/.ssh/agent.sock
+  [ -S "$SSH_AUTH_SOCK" ] && rm "$SSH_AUTH_SOCK"
+  socat UNIX-LISTEN:$SSH_AUTH_SOCK,fork EXEC:"npiperelay -ei -s //./pipe/openssh-ssh-agent",nofork &
+
+  if [ "$#" -gt 0 ]; then
+    SHLVL=0 exec "$SHELL" -c "$@"
+  else
+    SHLVL=0 exec "$SHELL"
+  fi
+}
+
 # Use OpenSSH for Windows by default.
 WSL_SSH_AGENT=false
 
@@ -29,30 +61,8 @@ while getopts ":wh" arg; do
 done
 
 if [ "$WSL_SSH_AGENT" = true ]; then
-  if [ "$#" -gt 0 ]; then
+  start_with_wsl_agent
-    SHLVL=0 exec ssh-agent "$SHELL" -c "$@"
 else
-    SHLVL=0 exec ssh-agent "$SHELL"
+  start_with_windows_agent
-  fi
 fi
 
-require() {
-  if ! command -v "$@" >/dev/null 2>&1; then
-    >&2 echo "ERROR: required command not found: $1"
-    exit 1
-  fi
-}
-
-require socat
-require npiperelay
-
-# Forward SSH Agent requests from withitn WSL to OpenSSH for Windows, based on:
-# https://stuartleeks.com/posts/wsl-ssh-key-forward-to-windows/
-export SSH_AUTH_SOCK=$HOME/.ssh/agent.sock
-[ -S "$SSH_AUTH_SOCK" ] && rm "$SSH_AUTH_SOCK"
-socat UNIX-LISTEN:$SSH_AUTH_SOCK,fork EXEC:"npiperelay -ei -s //./pipe/openssh-ssh-agent",nofork &
-if [ "$#" -gt 0 ]; then
-  SHLVL=0 exec "$SHELL" -c "$@"
-else
-  SHLVL=0 exec "$SHELL"
-fi