Fun with GPTs.

tools/install_mac_deps.sh

@@ -1,39 +1,64 @@
 #! /bin/bash
 
-# Script for building P4C on MacOS.
+# Script to install P4C dependencies on MacOS.
 
 set -e  # Exit on error.
 set -x  # Make command execution verbose
 
+# Installation helper.
+brew_install() {
+    echo "\nInstalling $1"
+    if brew list $1 &>/dev/null; then
+        echo "${1} is already installed"
+    else
+        brew install $1 && echo "$1 is installed"
+    fi
+}
 
-# Set up Homebrew differently for arm64.
-if [[ $(uname -m) == 'arm64' ]]; then
-    (echo; echo 'eval "$(/opt/homebrew/bin/brew shellenv)"') >> ~/.zprofile
-    eval "$(/opt/homebrew/bin/brew shellenv)"
-else
-    (echo; echo 'eval "$(/usr/local/bin/brew shellenv)"') >> ~/.zprofile
-    eval "$(/usr/local/bin/brew shellenv)"
+# Check if brew shellenv command is already in zprofile
+if ! grep -q 'brew shellenv' ~/.zprofile; then
+    # Set up Homebrew differently for arm64.
+    if [[ $(uname -m) == 'arm64' ]]; then
+        (echo; echo 'eval "$(/opt/homebrew/bin/brew shellenv)"') >> ~/.zprofile
+        eval "$(/opt/homebrew/bin/brew shellenv)"
+    else
+        (echo; echo 'eval "$(/usr/local/bin/brew shellenv)"') >> ~/.zprofile
+        eval "$(/usr/local/bin/brew shellenv)"
+    fi
 fi
+# Source zprofile.
+source ~/.zprofile
 
-if [[ ! -x brew ]]; then
-    /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
+# Check if Homebrew is already installed
+if ! which brew > /dev/null 2>&1; then
+  /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
 fi
 HOMEBREW_PREFIX=$(brew --prefix)
 
-# Install some custom requirements on OS X using brew
+
 BOOST_LIB="boost@1.84"
-brew install autoconf automake bdw-gc ccache cmake \
-      libtool openssl pkg-config coreutils bison grep \
-      ${BOOST_LIB}
-
-# We need to link boost and openssl.
-brew link ${BOOST_LIB} openssl
-# Prefer Homebrew's bison and grep over the macOS-provided version.
-# For Bison only `$(brew --prefix bison)/bin` seems to work...
-echo 'export PATH="$(brew --prefix bison)/bin:$PATH"' >> ~/.bash_profile
-echo 'export PATH="$HOMEBREW_PREFIX/opt/grep/libexec/gnubin:$PATH"' >> ~/.bash_profile
-source ~/.bash_profile
+REQUIRED_PACKAGES=(
+    autoconf automake bdw-gc ccache cmake libtool
+    openssl pkg-config coreutils bison grep
+    ${BOOST_LIB}
+)
+for package in "${REQUIRED_PACKAGES[@]}"; do
+  brew_install ${package}
+done
+
+# Check if linking is needed
+if ! brew ls --linked --formula ${BOOST_LIB} > /dev/null 2>&1; then
+  brew link ${BOOST_LIB}
+fi
 
+# Check if PATH modification is needed
+if ! grep -q "$(brew --prefix bison)/bin" ~/.bash_profile; then
+  echo 'export PATH="$(brew --prefix bison)/bin:$PATH"' >> ~/.bash_profile
+fi
+if ! grep -q "$HOMEBREW_PREFIX/opt/grep/libexec/gnubin" ~/.bash_profile; then
+  echo 'export PATH="$HOMEBREW_PREFIX/opt/grep/libexec/gnubin:$PATH"' >> ~/.bash_profile
+fi
+source ~/.bash_profile
 
 # Fixes for stuck grpcio installation.
 export GRPC_PYTHON_BUILD_SYSTEM_OPENSSL=1