Merge pull request #12 from djeada/strip_cpp_comments

add strip_cpp_comments.sh

Author: djeada

src/strip_cpp_comments.sh

@@ -0,0 +1,159 @@
+#!/usr/bin/env bash
+#
+# strip_comments.sh  —  Remove C / C++ comments from files *in place* (pure Bash)
+#
+# Usage:
+#   strip_comments.sh [-r REGEX] [file1 file2 …]
+#
+#   -r | --regex REGEX   Extended-regexp that candidate filenames must match.
+#                        If you omit every file argument, the script looks in
+#                        the current directory and processes *all* regular files
+#                        that match REGEX.
+#
+# Default REGEX :  \.([ch](pp|xx|c)?|cc|hh|hpp)$   # .c .h .cpp .cc .cxx .hpp …
+#
+# Exit codes:
+#   0  OK
+#   1  bad usage / no files found
+#   2  cannot read / write file
+#
+
+set -euo pipefail
+IFS=$'\n\t'
+
+##############################################################################
+# CONFIG
+##############################################################################
+DEFAULT_RE='\.([ch](pp|xx|c)?|cc|hh|hpp)$'   # .c .h .cpp .cc .cxx .hpp …
+
+##############################################################################
+# FUNCTION: strip_file  (unchanged)
+##############################################################################
+strip_file() {
+    local file=$1
+    local tmp
+    tmp=$(mktemp "${TMPDIR:-/tmp}/scrub.XXXXXX") || {
+        echo "Error: cannot create temp file" >&2; return 2; }
+
+    # State variables
+    local in_block=0 in_line=0 in_str=0 in_char=0 escape=0
+    local prev='' c=''
+
+    # FD 3 → tmp
+    exec 3> "$tmp"
+
+    while IFS= read -r -N1 c || [[ -n $c ]]; do
+        # ---------- end of line comment ----------
+        if (( in_line )); then
+            if [[ $c == $'\n' ]]; then
+                in_line=0
+                printf '\n' >&3
+            fi
+            continue
+        fi
+
+        # ---------- end of block comment ----------
+        if (( in_block )); then
+            if [[ $prev == '*' && $c == '/' ]]; then
+                in_block=0
+                prev=''
+            else
+                prev=$c
+            fi
+            continue
+        fi
+
+        # ---------- inside string ----------
+        if (( in_str )); then
+            printf '%s' "$c" >&3
+            if (( escape )); then
+                escape=0
+            elif [[ $c == "\\" ]]; then
+                escape=1
+            elif [[ $c == '"' ]]; then
+                in_str=0
+            fi
+            continue
+        fi
+
+        # ---------- inside character ----------
+        if (( in_char )); then
+            printf '%s' "$c" >&3
+            if (( escape )); then
+                escape=0
+            elif [[ $c == "\\" ]]; then
+                escape=1
+            elif [[ $c == "'" ]]; then
+                in_char=0
+            fi
+            continue
+        fi
+
+        # ---------- neutral ----------
+        if [[ -z $prev ]]; then
+            case $c in
+                /)   prev='/' ;;                     # might start comment
+                '"') in_str=1 ; printf '%s' "$c" >&3 ;;
+                "'") in_char=1; printf '%s' "$c" >&3 ;;
+                *)   printf '%s' "$c" >&3 ;;
+            esac
+        else
+            case $c in
+                /)  in_line=1 ; prev='' ;;           # "//"
+                \*) in_block=1; prev='' ;;           # "/*"
+                *)  printf '/%s' "$c" >&3; prev='' ;;
+            esac
+        fi
+    done < "$file"
+
+    [[ -n $prev ]] && printf '%s' "$prev" >&3     # lone '/'
+
+    chmod --reference="$file" "$tmp"
+    mv "$tmp" "$file"
+}
+
+##############################################################################
+# FUNCTION: main  (argument logic updated)
+##############################################################################
+main() {
+    local regex=$DEFAULT_RE
+    local positional=()
+
+    # ------ parse args ------
+    while [[ $# -gt 0 ]]; do
+        case $1 in
+            -r|--regex)
+                shift
+                [[ $# -eq 0 ]] && { echo "Error: -r needs ARG" >&2; exit 1; }
+                regex=$1
+                ;;
+            -*)
+                echo "Unknown option: $1" >&2; exit 1 ;;
+            *)
+                positional+=("$1")
+                ;;
+        esac
+        shift
+    done
+
+    # ------ auto-discover files if none listed ------
+    if (( ${#positional[@]} == 0 )); then
+        for f in *; do
+            [[ -f $f && $f =~ $regex ]] && positional+=("$f")
+        done
+    fi
+
+    (( ${#positional[@]} )) || { echo "Error: no files match '$regex'" >&2; exit 1; }
+
+    # ------ process ------
+    for f in "${positional[@]}"; do
+        [[ $f =~ $regex ]] || { echo "Skip: $f (no match)" >&2; continue; }
+        [[ -r $f && -w $f ]] || { echo "Error: cannot read/write $f" >&2; exit 2; }
+        echo "Stripping comments from $f ..."
+        strip_file "$f" || exit $?
+    done
+
+    echo "Done."
+}
+
+main "$@"