lint: Add .clang-tidy and analyzer scripts

Signed-off-by: John Studnicka <contact@zentec.dev>

.clang-tidy

@@ -0,0 +1,18 @@
+Checks: >
+  clang-analyzer-*,
+  -clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling,
+  bugprone-*,
+  -bugprone-easily-swappable-parameters,
+  -bugprone-reserved-identifier,
+  hicpp-no-assembler,
+  misc-include-cleaner,
+  performance-*,
+  portability-*,
+  readability-redundant-control-flow
+
+HeaderFilterRegex: '.*'
+WarningsAsErrors: ''
+
+CheckOptions:
+  misc-include-cleaner.UnusedIncludes: 'true'
+  misc-include-cleaner.MissingIncludes: 'false'

.github/scripts/clang-tidy-analyze.sh

@@ -0,0 +1,321 @@
+#!/bin/sh
+set -eu
+
+default_build_dir="build"
+build_dir=""
+jobs=1
+show_total=0
+target_only=0
+total_only=0
+warnings_only=0
+errors_only=0
+target=""
+target_kind="all"
+target_file_abs=""
+
+usage() {
+	echo "Usage: $0 [-p BUILD_DIR] [-j N] [--warnings-only|--errors-only] [-t|--total] [--target-only] [--total-only] [target]" >&2
+	echo "  target: optional .c/.h file path or directory path to check; omit for whole project." >&2
+	echo "  -p DIR: compile database directory. Defaults to ./compile_commands.json, then $default_build_dir/compile_commands.json." >&2
+	echo "  -j N:  number of parallel clang-tidy jobs (positive integer, default: 1)." >&2
+	echo "  -t, --total: append TOTAL counts after per-file counts." >&2
+	echo "  --warnings-only: print warning counts only." >&2
+	echo "  --errors-only: print error counts only." >&2
+	echo "  --target-only: for file targets, count diagnostics only in that file (exclude headers)." >&2
+	echo "  --total-only: print only TOTAL counts (no per-file breakdown)." >&2
+	echo "" >&2
+	echo "Examples:" >&2
+	echo "  $0 -j 8 --total" >&2
+	echo "  $0 -j 8 hw/xfree86" >&2
+	echo "  $0 --target-only hw/xfree86/drivers/video/modesetting/drmmode_display.c" >&2
+	echo "" >&2
+	echo "Requires: clang-tidy, jq, and a Meson compile_commands.json database." >&2
+}
+
+while [ "$#" -gt 0 ]; do
+	case "$1" in
+	-h | --help)
+		usage
+		exit 0
+		;;
+	-t | --total)
+		show_total=1
+		shift
+		;;
+	--warnings-only)
+		warnings_only=1
+		shift
+		;;
+	--errors-only)
+		errors_only=1
+		shift
+		;;
+	-p)
+		if [ "$#" -lt 2 ]; then
+			echo "Missing value for -p." >&2
+			usage
+			exit 2
+		fi
+		build_dir="$2"
+		shift 2
+		;;
+	--target-only)
+		target_only=1
+		shift
+		;;
+	--total-only)
+		total_only=1
+		show_total=1
+		shift
+		;;
+	-j)
+		if [ "$#" -lt 2 ]; then
+			echo "Missing value for -j." >&2
+			usage
+			exit 2
+		fi
+		jobs="$2"
+		case "$jobs" in
+		'' | *[!0-9]* | 0)
+			echo "Invalid -j value: $jobs (expected positive integer)." >&2
+			usage
+			exit 2
+			;;
+		esac
+		shift 2
+		;;
+	--)
+		shift
+		break
+		;;
+	-*)
+		echo "Unknown option: $1" >&2
+		usage
+		exit 2
+		;;
+	*) break ;;
+	esac
+done
+
+if [ "$#" -gt 1 ]; then
+	echo "Expected at most one target argument." >&2
+	usage
+	exit 2
+elif [ "$#" -eq 1 ]; then
+	target="$1"
+fi
+
+if [ "$warnings_only" -eq 1 ] && [ "$errors_only" -eq 1 ]; then
+	echo "--warnings-only and --errors-only are incompatible." >&2
+	usage
+	exit 2
+fi
+
+if ! command -v clang-tidy >/dev/null 2>&1; then
+	echo "clang-tidy not found in PATH." >&2
+	exit 1
+fi
+
+if ! command -v jq >/dev/null 2>&1; then
+	echo "jq not found in PATH." >&2
+	exit 1
+fi
+
+if [ -n "$build_dir" ]; then
+	compdb_dir="$build_dir"
+elif [ -f compile_commands.json ]; then
+	compdb_dir="."
+else
+	compdb_dir="$default_build_dir"
+fi
+
+if [ ! -d "$compdb_dir" ]; then
+	echo "Compile database directory '$compdb_dir' not found. Run meson setup first." >&2
+	exit 1
+fi
+
+compdb="$compdb_dir/compile_commands.json"
+if [ ! -f "$compdb" ]; then
+	echo "Compilation database '$compdb' not found. Run meson setup first." >&2
+	exit 1
+fi
+
+compdb_dir_abs="$(cd "$compdb_dir" && pwd -P)"
+tmp_outdir="$(mktemp -d)"
+tmp_files="$tmp_outdir/files.txt"
+tmp_files_nul="$tmp_outdir/files.nul"
+tmp_parsed="$tmp_outdir/parsed.txt"
+trap 'rm -rf "$tmp_outdir"' EXIT INT TERM HUP
+
+first_dir="$(jq -r '.[0].directory // empty' "$compdb")"
+case "$first_dir" in
+/*) diag_base="$(cd "$first_dir" && pwd -P)" ;;
+"") diag_base="$compdb_dir_abs" ;;
+*) diag_base="$(cd "$compdb_dir/$first_dir" && pwd -P)" ;;
+esac
+
+canonical_path() {
+	if command -v realpath >/dev/null 2>&1; then
+		realpath "$1"
+	else
+		dir=$(dirname "$1")
+		base=$(basename "$1")
+		printf '%s/%s\n' "$(cd "$dir" && pwd -P)" "$base"
+	fi
+}
+
+emit_compdb_files() {
+	jq -r '.[] | [.directory, .file] | @tsv' "$compdb" |
+		while IFS="$(printf '\t')" read -r dir file; do
+			case "$file" in
+			/*) canonical_path "$file" ;;
+			*) canonical_path "$dir/$file" ;;
+			esac
+		done |
+		awk '!seen[$0]++'
+}
+
+if [ -n "$target" ] && [ -f "$target" ]; then
+	target_kind="file"
+	target_file_abs="$(canonical_path "$target")"
+	case "$target" in
+	*.c | *.h) printf '%s\n' "$target_file_abs" >"$tmp_files" ;;
+	*)
+		echo "Not a .c or .h file: $target" >&2
+		exit 2
+		;;
+	esac
+elif [ -n "$target" ] && [ -d "$target" ]; then
+	target_kind="dir"
+	target_dir_abs="$(canonical_path "$target")"
+	emit_compdb_files |
+		while IFS= read -r file; do
+			case "$file" in
+			"$target_dir_abs" | "$target_dir_abs"/*) printf '%s\n' "$file" ;;
+			esac
+		done >"$tmp_files"
+elif [ -n "$target" ]; then
+	echo "Path not found: $target" >&2
+	exit 2
+else
+	emit_compdb_files >"$tmp_files"
+fi
+
+if [ "$target_only" -eq 1 ] && [ "$target_kind" != "file" ]; then
+	echo "--target-only requires a file target." >&2
+	exit 2
+fi
+
+if [ ! -s "$tmp_files" ]; then
+	if [ "$show_total" -eq 1 ]; then
+		if [ "$warnings_only" -eq 1 ] || [ "$errors_only" -eq 1 ]; then
+			printf "0\tTOTAL\n"
+		else
+			printf "0\t0\tTOTAL\n"
+		fi
+	fi
+	exit 0
+fi
+
+while IFS= read -r file; do
+	printf '%s\0' "$file"
+done <"$tmp_files" >"$tmp_files_nul"
+
+emit_clang_output() {
+	if command -v xargs >/dev/null 2>&1; then
+		xargs -0 -n 1 -P "$jobs" clang-tidy -p "$compdb_dir_abs" <"$tmp_files_nul" 2>&1 || true
+	else
+		while IFS= read -r file; do
+			clang-tidy -p "$compdb_dir_abs" "$file" 2>&1 || true
+		done <"$tmp_files"
+	fi
+}
+
+emit_clang_output |
+	awk -F: \
+		-v base="$diag_base" \
+		-v target_only="$target_only" \
+		-v target_file="$target_file_abs" '
+        function canon(p,   abs, n, i, part, top, stack, out) {
+            if (p ~ /^\//) {
+                abs = p
+            } else {
+                abs = base "/" p
+            }
+            n = split(abs, stack, "/")
+            top = 0
+            for (i = 1; i <= n; i++) {
+                part = stack[i]
+                if (part == "" || part == ".") {
+                    continue
+                }
+                if (part == "..") {
+                    if (top > 0) {
+                        top--
+                    }
+                    continue
+                }
+                top++
+                stack[top] = part
+            }
+            out = ""
+            for (i = 1; i <= top; i++) {
+                out = out "/" stack[i]
+            }
+            return (out == "" ? "/" : out)
+        }
+        {
+            if ($0 !~ /^([^:[:space:]]+):([1-9][0-9]*):([1-9][0-9]*): (warning|error): .+ \[[[:alnum:].,-]+\]$/) {
+                next
+            }
+
+            file = canon($1)
+            if (target_only == 1 && file != target_file) {
+                next
+            }
+
+            if ($0 ~ /: warning: /) {
+                warnings[file]++
+                total_warnings++
+            } else {
+                errors[file]++
+                total_errors++
+            }
+            seen[file] = 1
+        }
+        END {
+            for (file in seen) {
+                printf "%d\t%d\t%s\n", warnings[file] + 0, errors[file] + 0, file
+            }
+            printf "__TOTAL__\t%d\t%d\n", total_warnings + 0, total_errors + 0
+        }
+    ' >"$tmp_parsed"
+
+print_counts() {
+	while IFS="$(printf '\t')" read -r warnings errors file; do
+		if [ "$warnings_only" -eq 1 ]; then
+			printf '%s\t%s\n' "$warnings" "$file"
+		elif [ "$errors_only" -eq 1 ]; then
+			printf '%s\t%s\n' "$errors" "$file"
+		else
+			printf '%s\t%s\t%s\n' "$warnings" "$errors" "$file"
+		fi
+	done
+}
+
+if [ "$total_only" -eq 0 ]; then
+	grep -v '^__TOTAL__' "$tmp_parsed" | sort -nr | print_counts
+fi
+
+if [ "$show_total" -eq 1 ]; then
+	total_line="$(grep '^__TOTAL__' "$tmp_parsed")"
+	total_warnings="$(printf '%s\n' "$total_line" | cut -f2)"
+	total_errors="$(printf '%s\n' "$total_line" | cut -f3)"
+	if [ "$warnings_only" -eq 1 ]; then
+		printf '%s\tTOTAL\n' "$total_warnings"
+	elif [ "$errors_only" -eq 1 ]; then
+		printf '%s\tTOTAL\n' "$total_errors"
+	else
+		printf '%s\t%s\tTOTAL\n' "$total_warnings" "$total_errors"
+	fi
+fi

.github/scripts/link-compile-commands.sh

@@ -0,0 +1,27 @@
+#!/bin/sh
+set -eu
+
+build_dir="${1:-build}"
+root_link="compile_commands.json"
+
+case "$(uname -s 2>/dev/null || echo unknown)" in
+MINGW* | MSYS* | CYGWIN*)
+	echo "Skipping compile_commands.json symlink on non-Unix platform." >&2
+	exit 0
+	;;
+esac
+
+if [ ! -f "$build_dir/compile_commands.json" ]; then
+	echo "Compilation database '$build_dir/compile_commands.json' not found. Run meson setup first." >&2
+	exit 1
+fi
+
+if [ -e "$root_link" ] && [ ! -L "$root_link" ]; then
+	echo "Refusing to overwrite non-symlink '$root_link'." >&2
+	exit 1
+fi
+
+tmp_link="$root_link.tmp.$$"
+rm -f "$tmp_link"
+ln -s "$build_dir/compile_commands.json" "$tmp_link"
+mv -f "$tmp_link" "$root_link"

.github/scripts/meson-build.sh

@@ -5,6 +5,8 @@
 #
 # SPDX-License-Identifier: MIT
 #
+# shellcheck disable=SC1091,SC2086
+#
 # Usage:
 #     meson-build.sh
 #       [-C directory]			... change to directory before doing anything
@@ -39,47 +41,47 @@ MESON_RUN_DIST="$MESON_DIST_ARGS"
 
 while [[ $# -gt 0 ]]; do
 	case $1 in
-		-C)
-			directory=$2
-			shift 2
-			pushd "$directory" || exit 1
-			;;
-		--skip-setup)
-			shift
-			MESON_SKIP_SETUP="1"
-			;;
-		--skip-build)
-			shift
-			MESON_SKIP_BUILD="1"
-			;;
-		--skip-test)
-			shift
-			MESON_RUN_TEST=""
-			;;
-		--run-test)
-			shift
-			MESON_RUN_TEST="1"
-			;;
-		--skip-dist)
-			shift
-			MESON_RUN_DIST=""
-			;;
-		--run-dist)
-			shift
-			MESON_RUN_DIST="1"
-			;;
-		--skip-install)
-			shift
-			MESON_RUN_INSTALL=""
-			;;
-		--run-install)
-			shift
-			MESON_RUN_INSTALL="1"
-			;;
-		*)
-			echo "Unknow commandline argument $1"
-			exit 1
-			;;
+	-C)
+		directory=$2
+		shift 2
+		pushd "$directory" || exit 1
+		;;
+	--skip-setup)
+		shift
+		MESON_SKIP_SETUP="1"
+		;;
+	--skip-build)
+		shift
+		MESON_SKIP_BUILD="1"
+		;;
+	--skip-test)
+		shift
+		MESON_RUN_TEST=""
+		;;
+	--run-test)
+		shift
+		MESON_RUN_TEST="1"
+		;;
+	--skip-dist)
+		shift
+		MESON_RUN_DIST=""
+		;;
+	--run-dist)
+		shift
+		MESON_RUN_DIST="1"
+		;;
+	--skip-install)
+		shift
+		MESON_RUN_INSTALL=""
+		;;
+	--run-install)
+		shift
+		MESON_RUN_INSTALL="1"
+		;;
+	*)
+		echo "Unknow commandline argument $1"
+		exit 1
+		;;
 	esac
 done
 
@@ -124,6 +126,7 @@ if [[ -z "$MESON_SKIP_SETUP" ]]; then
 	meson setup "$MESON_BUILDDIR" $MESON_ARGS
 fi
 meson configure "$MESON_BUILDDIR"
+.github/scripts/link-compile-commands.sh "$MESON_BUILDDIR"
 
 if [[ -z "$MESON_SKIP_BUILD" ]]; then
 	if [[ -n "$NINJA_ARGS" ]]; then
@@ -137,7 +140,7 @@ if [[ -n "$MESON_RUN_TEST" ]]; then
 fi
 
 if [[ -n "$MESON_RUN_INSTALL" ]]; then
-	meson install --no-rebuild  -C "$MESON_BUILDDIR" $MESON_INSTALL_ARGS
+	meson install --no-rebuild -C "$MESON_BUILDDIR" $MESON_INSTALL_ARGS
 fi
 
 if [[ -n "$MESON_RUN_DIST" ]]; then

.gitignore

@@ -2,3 +2,6 @@
 *.swp
 *.patch
 tags
+compile_commands.json
+.vscode/*
+!.vscode/tasks.json

.vscode/tasks.json

@@ -0,0 +1,95 @@
+{
+    "version": "2.0.0",
+    "tasks": [
+        {
+            "label": "clang-tidy (current file)",
+            "type": "shell",
+            "command": "clang-tidy",
+            "args": [
+                "${file}"
+            ],
+            "problemMatcher": "$gcc",
+            "group": {
+                "kind": "build",
+                "isDefault": false
+            }
+        },
+        {
+            "label": "meson setup (clang)",
+            "type": "shell",
+            "command": "sh",
+            "args": [
+                "-c",
+                "if [ -d build ]; then meson setup build --reconfigure; else meson setup build; fi && .github/scripts/link-compile-commands.sh build"
+            ],
+            "options": {
+                "env": {
+                    "CC": "clang",
+                    "CXX": "clang++"
+                }
+            },
+            "problemMatcher": []
+        },
+        {
+            "label": "ninja (build, clang)",
+            "type": "shell",
+            "command": "ninja",
+            "args": [
+                "-C",
+                "build"
+            ],
+            "dependsOn": [
+                "meson setup (clang)"
+            ],
+            "problemMatcher": "$gcc",
+            "group": {
+                "kind": "build",
+                "isDefault": false
+            }
+        },
+        {
+            "label": "meson setup (gcc)",
+            "type": "shell",
+            "command": "sh",
+            "args": [
+                "-c",
+                "if [ -d build ]; then meson setup build --reconfigure; else meson setup build; fi && .github/scripts/link-compile-commands.sh build"
+            ],
+            "options": {
+                "env": {
+                    "CC": "gcc",
+                    "CXX": "g++"
+                }
+            },
+            "problemMatcher": []
+        },
+        {
+            "label": "ninja (build, gcc)",
+            "type": "shell",
+            "command": "ninja",
+            "args": [
+                "-C",
+                "build"
+            ],
+            "dependsOn": [
+                "meson setup (gcc)"
+            ],
+            "problemMatcher": "$gcc",
+            "group": {
+                "kind": "build",
+                "isDefault": true
+            }
+        },
+        {
+            "label": "clang-tidy (all files)",
+            "type": "shell",
+            "command": ".github/scripts/clang-tidy-analyze.sh",
+            "args": [
+                "-j",
+                "4",
+                "--total"
+            ],
+            "problemMatcher": []
+        }
+    ]
+}