avoid breaking pacman.conf if entries already exist

setup-dev.sh

@@ -112,17 +112,27 @@ install_apt() {
 install_pacman() {
     set_zigpath "$(pwd)/.zig"
 
-    # add debug repo for glibc-debug
-    cat << EOF | sudo tee -a /etc/pacman.conf
-[core-debug]
-Include = /etc/pacman.d/mirrorlist
+    # add debug repo for glibc-debug if it doesn't already exist
+    if ! grep -q "\[core-debug\]" /etc/pacman.conf; then
+        cat << EOF | sudo tee -a /etc/pacman.conf
+        [core-debug]
+        Include = /etc/pacman.d/mirrorlist
+EOF
+    fi
 
-[extra-debug]
-Include = /etc/pacman.d/mirrorlist
+    if ! grep -q "\[extra-debug\]" /etc/pacman.conf; then
+        cat << EOF | sudo tee -a /etc/pacman.conf
+        [extra-debug]
+        Include = /etc/pacman.d/mirrorlist
+EOF
+    fi
 
-[multilib-debug]
-Include = /etc/pacman.d/mirrorlist
+    if ! grep -q "\[multilib-debug\]" /etc/pacman.conf; then
+        cat << EOF | sudo tee -a /etc/pacman.conf
+        [multilib-debug]
+        Include = /etc/pacman.d/mirrorlist
 EOF
+    fi
 
     sudo pacman -Syu --noconfirm || true
     sudo pacman -S --needed --noconfirm \
@@ -132,8 +142,12 @@ EOF
         curl \
         base-devel \
         gdb \
-        parallel \
-        gnu-netcat
+        parallel
+
+    # check if netcat exists first, as it might it may be installed from some other netcat packages
+    if [ ! -f /usr/bin/nc ]; then
+        sudo pacman -S --needed --noconfirm gnu-netcat
+    fi
 
     command -v go &> /dev/null || sudo pacman -S --noconfirm go