diff --git a/scripts/check-commitlog.sh b/scripts/check-commitlog.sh
index e12589250..23cd3f4bb 100755
--- a/scripts/check-commitlog.sh
+++ b/scripts/check-commitlog.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 # Check that every non-merge commit after the specified base commit has a commit
 # message ending with a valid Change-Id line. A valid Change-Id line must be the
@@ -8,6 +8,16 @@
 #
 # Merge commits are excluded from this check.
 
+# Ensure that the common script exists and is readable, then verify it has no
+# syntax errors and defines the required function.
+common_script="$(dirname "$0")/common.sh"
+[ -r "$common_script" ] || { echo "[!] '$common_script' not found or not readable." >&2; exit 1; }
+bash -n "$common_script" >/dev/null 2>&1 || { echo "[!] '$common_script' contains syntax errors." >&2; exit 1; }
+source "$common_script"
+declare -F set_colors >/dev/null 2>&1 || { echo "[!] '$common_script' does not define the required function." >&2; exit 1; }
+
+set_colors
+
 # Base commit from which to start checking.
 BASE_COMMIT="0b8be2c15160c216e8b6ec82c99a000e81c0e429"
 
@@ -33,10 +43,7 @@ for commit in $commits; do
 done
 
 if [ $failed -ne 0 ]; then
-  echo
-  echo "Some commits are missing a valid Change-Id. Please amend the commit messages accordingly."
-  echo
-  exit 1
+  throw "Some commits are missing a valid Change-Id. Please amend the commit messages accordingly."
 fi
 
 exit 0
diff --git a/scripts/check-repo.sh b/scripts/check-repo.sh
index 28d40f995..b0f9846bd 100755
--- a/scripts/check-repo.sh
+++ b/scripts/check-repo.sh
@@ -1,7 +1,14 @@
 #!/usr/bin/env bash
 
-# Source the common utilities
-source "$(dirname "$0")/common.sh"
+# Ensure that the common script exists and is readable, then verify it has no
+# syntax errors and defines the required function.
+common_script="$(dirname "$0")/common.sh"
+[ -r "$common_script" ] || { echo "[!] '$common_script' not found or not readable." >&2; exit 1; }
+bash -n "$common_script" >/dev/null 2>&1 || { echo "[!] '$common_script' contains syntax errors." >&2; exit 1; }
+source "$common_script"
+declare -F set_colors >/dev/null 2>&1 || { echo "[!] '$common_script' does not define the required function." >&2; exit 1; }
+
+set_colors
 
 check_github_actions
 
diff --git a/scripts/checksums b/scripts/checksums
index 87ff044d7..533a53afd 100644
--- a/scripts/checksums
+++ b/scripts/checksums
@@ -1,3 +1,3 @@
 398b59c23f699ff1bf1e73a94503a9a91caa9207  queue.h
 9be9666430f392924f5d27caa71a412527bf9267  list.h
-3bb0192cee08d165fd597a9f6fbb404533e28fcf  scripts/check-commitlog.sh
+1029c2784b4cae3909190c64f53a06cba12ea38e  scripts/check-commitlog.sh
diff --git a/scripts/commit-msg.hook b/scripts/commit-msg.hook
index 498cc7680..71ffad1c5 100755
--- a/scripts/commit-msg.hook
+++ b/scripts/commit-msg.hook
@@ -11,31 +11,20 @@ HOOK_EDITOR=
 SKIP_DISPLAY_WARNINGS=0
 WARNINGS=
 
-RED=
-YELLOW=
-BLUE=
-WHITE=
-CYAN=
-NC=
-
-# Set colour variables if the output should be coloured.
-set_colors() {
-  local default_color=$(git config --get hooks.goodcommit.color || git config --get color.ui || echo 'auto')
-  if [[ $default_color == 'always' ]] || [[ $default_color == 'auto' && -t 1 ]]; then
-    RED='\033[1;31m'
-    YELLOW='\033[1;33m'
-    BLUE='\033[1;34m'
-    WHITE='\033[1;37m'
-    CYAN='\033[1;36m'
-    NC='\033[0m' # No Color
-  fi
-}
+# Ensure that the common script exists and is readable, then verify it has no
+# syntax errors and defines the required function.
+common_script="$(dirname "$0")/../../scripts/common.sh"
+[ -r "$common_script" ] || { echo "[!] '$common_script' not found or not readable." >&2; exit 1; }
+bash -n "$common_script" >/dev/null 2>&1 || { echo "[!] '$common_script' contains syntax errors." >&2; exit 1; }
+source "$common_script"
+declare -F set_colors >/dev/null 2>&1 || { echo "[!] '$common_script' does not define the required function." >&2; exit 1; }
 
 # Set the hook editor, using the same approach as git.
 set_editor() {
-  # $GIT_EDITOR appears to always be set to `:` when the hook is executed by Git?
-  # ref: http://stackoverflow.com/q/41468839/885540
-  # ref: https://github.com/tommarshall/git-good-commit/issues/11
+  # $GIT_EDITOR appears to always be set to ':' when the hook is executed by Git?
+  # Reference:
+  # - http://stackoverflow.com/q/41468839/885540
+  # - https://github.com/tommarshall/git-good-commit/issues/11
   # HOOK_EDITOR=$GIT_EDITOR
   test -z "${HOOK_EDITOR}" && HOOK_EDITOR=$(git config --get core.editor)
   test -z "${HOOK_EDITOR}" && HOOK_EDITOR=$VISUAL
diff --git a/scripts/common.sh b/scripts/common.sh
index 1890c430b..bb6353ebf 100644
--- a/scripts/common.sh
+++ b/scripts/common.sh
@@ -102,5 +102,3 @@ make_random_string() {
     echo "${raw_rand:0:pos}${sub_str}${raw_rand:pos}"
   fi
 }
-
-set_colors
diff --git a/scripts/install-git-hooks b/scripts/install-git-hooks
index 7fec80501..53b68a25d 100755
--- a/scripts/install-git-hooks
+++ b/scripts/install-git-hooks
@@ -1,16 +1,40 @@
 #!/usr/bin/env bash
 
+# Ensure that the common script exists and is readable, then verify it has no
+# syntax errors and defines the required function.
+common_script="$(dirname "$0")/common.sh"
+[ -r "$common_script" ] || { echo "[!] '$common_script' not found or not readable." >&2; exit 1; }
+bash -n "$common_script" >/dev/null 2>&1 || { echo "[!] '$common_script' contains syntax errors." >&2; exit 1; }
+source "$common_script"
+declare -F set_colors >/dev/null 2>&1 || { echo "[!] '$common_script' does not define the required function." >&2; exit 1; }
+
+set_colors
+
+TOTAL_STEPS=5
+CURRENT_STEP=0
+
+# 1. Validate the workspace
+((CURRENT_STEP++))
+progress "$CURRENT_STEP" "$TOTAL_STEPS"
+
 if ! test -d .git; then
-    echo "Execute scripts/install-git-hooks in the top-level directory."
-    exit 1
+  throw "Execute scripts/install-git-hooks in the top-level directory."
+fi
+
+workspace=$(git rev-parse --show-toplevel)
+if [ ! -d "$workspace" ]; then
+  throw "The workspace path '$workspace' contains non-ASCII characters."
 fi
 
+# 2. Check GitHub account
+((CURRENT_STEP++))
+progress "$CURRENT_STEP" "$TOTAL_STEPS"
+
 ACCOUNT=$(git config -l | grep -w remote.origin.url | sed -e 's/^.*github.com[\/:]\(.*\)\/lab0-c.*/\1/')
 
 CURL=$(which curl)
 if [ $? -ne 0 ]; then
-    echo "[!] curl not installed." >&2
-    exit 1
+  throw "curl not installed."
 fi
 
 CURL_RES=$(${CURL} -s \
@@ -19,44 +43,51 @@ https://api.github.com/repos/${ACCOUNT}/lab0-c/actions/workflows)
 
 TOTAL_COUNT=$(echo ${CURL_RES} | sed -e 's/.*"total_count": \([^,"]*\).*/\1/')
 case ${TOTAL_COUNT} in
-    *"Not Found"*)
-        echo "Check your repository. It should be located at https://github.com/${ACCOUNT}/lab0-c"
-        exit 1
+  *"Not Found"*)
+    throw "Check your repository. It should be located at https://github.com/${ACCOUNT}/lab0-c"
 esac
 
+# 3. Ensure this repository is frok from sysprog21/lab0-c'.
+((CURRENT_STEP++))
+progress "$CURRENT_STEP" "$TOTAL_STEPS"
+
 if [[ "${ACCOUNT}" != "sysprog21" ]]; then
-    REPO_FORKED=$(${CURL} -s \
-    -H "Accept: application/vnd.github.v3+json" \
-    https://api.github.com/repos/${ACCOUNT}/lab0-c | grep -m 1 fork)
-    case ${REPO_FORKED} in
-        *true*)
-            ;;
-        *)
-            echo "Your repository MUST be forked from sysprog21/lab0-c"
-            exit 1
-    esac
+  REPO_FORKED=$(${CURL} -s \
+                -H "Accept: application/vnd.github.v3+json" \
+                https://api.github.com/repos/${ACCOUNT}/lab0-c | grep -m 1 fork)
+  case ${REPO_FORKED} in
+    *true*)
+      ;;
+    *)
+      throw "Your repository MUST be forked from 'sysprog21/lab0-c'."
+  esac
 fi
 
+# 4. Check GitHub Actions
+((CURRENT_STEP++))
+progress "$CURRENT_STEP" "$TOTAL_STEPS"
+
 if [ ${TOTAL_COUNT} -eq "0" ]; then
-    echo "Fatal: GitHub Actions MUST be activated."
-    case ${OSTYPE} in
-        "linux"*)
-            xdg-open https://github.com/${ACCOUNT}/lab0-c/actions > /dev/null 2>&1
-            ;;
-        "darwin"*)
-            open https://github.com/${ACCOUNT}/lab0-c/actions
-            ;;
-        *)
-            echo "Please activate at https://github.com/${ACCOUNT}/lab0-c/actions"
-            ;;
-    esac
-    echo "Check this article: https://docs.github.com/en/actions/managing-workflow-runs/disabling-and-enabling-a-workflow"
-    echo "Then, execute 'make' again."
-    exit 1
-else
-    echo "GitHub Actions has been activated"
+  printf "\n[!] GitHub Actions MUST be activated."
+  case ${OSTYPE} in
+    "linux"*)
+      xdg-open https://github.com/${ACCOUNT}/lab0-c/actions > /dev/null 2>&1
+      ;;
+    "darwin"*)
+      open https://github.com/${ACCOUNT}/lab0-c/actions
+      ;;
+    *)
+      echo "Please activate at https://github.com/${ACCOUNT}/lab0-c/actions"
+      ;;
+  esac
+  throw "Check this article: https://docs.github.com/en/actions/managing-workflow-runs/disabling-and-enabling-a-workflow\n\
+    Then, execute 'make' again."
 fi
 
+# 5. Install Git hooks
+((CURRENT_STEP++))
+progress "$CURRENT_STEP" "$TOTAL_STEPS"
+
 mkdir -p .git/hooks
 
 ln -sf ../../scripts/pre-commit.hook .git/hooks/pre-commit || exit 1
diff --git a/scripts/pre-push.hook b/scripts/pre-push.hook
index ce8bb4b52..c1b457257 100755
--- a/scripts/pre-push.hook
+++ b/scripts/pre-push.hook
@@ -1,11 +1,17 @@
 #!/usr/bin/env bash
 
+# Ensure that the common script exists and is readable, then verify it has no
+# syntax errors and defines the required function.
+common_script="$(dirname "$0")/../../scripts/common.sh"
+[ -r "$common_script" ] || { echo "[!] '$common_script' not found or not readable." >&2; exit 1; }
+bash -n "$common_script" >/dev/null 2>&1 || { echo "[!] '$common_script' contains syntax errors." >&2; exit 1; }
+source "$common_script"
+declare -F set_colors >/dev/null 2>&1 || { echo "[!] '$common_script' does not define the required function." >&2; exit 1; }
+
+set_colors
+
 protected_branch='master'
 current_branch=$(git symbolic-ref HEAD | sed -e 's,.*/\(.*\),\1,')
-RED='\033[0;31m'
-GREEN='\033[1;32m'
-YELLOW='\033[1;33m'
-NC='\033[0m' # No Color
 
 # Validate repository
 # commit 50c5ac53d31adf6baac4f8d3db6b3ce2215fee40
diff --git a/scripts/prepare-commit-msg.hook b/scripts/prepare-commit-msg.hook
index 5a097c558..207795e40 100755
--- a/scripts/prepare-commit-msg.hook
+++ b/scripts/prepare-commit-msg.hook
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 COMMIT_MSG_FILE="$1"