cmux-cua Skill

1#!/usr/bin/env bash2# Shared, ownership-safe skill-link policy for the Claude and Codex wrappers.3#4# This file is bundled inside the signed cmux-cua resource and sourced by both5# wrappers. It deliberately has no launch side effects until6# cmux_cua_skill_reconcile is called by a cmux-owned session.7 8 9cmux_cua_skill_readlink() {10    /usr/bin/readlink "$1" 2>/dev/null || /bin/readlink "$1" 2>/dev/null11}12 13cmux_cua_skill_lexical_normalize() {14    local path="$1"15    [[ "$path" = /* ]] || return 116    local normalized="/"17    local remaining="${path#/}"18    local component19    while [[ -n "$remaining" ]]; do20        if [[ "$remaining" == */* ]]; then21            component="${remaining%%/*}"22            remaining="${remaining#*/}"23        else24            component="$remaining"25            remaining=""26        fi27        case "$component" in28            ""|.) continue ;;29            ..)30                if [[ "$normalized" != "/" ]]; then31                    normalized="${normalized%/*}"32                    [[ -n "$normalized" ]] || normalized="/"33                fi34                ;;35            *)36                if [[ "$normalized" == "/" ]]; then37                    normalized="/$component"38                else39                    normalized="$normalized/$component"40                fi41                ;;42        esac43    done44    printf '%s' "$normalized"45}46 47cmux_cua_skill_resolve_link_target() {48    local link="$1"49    local target="$2"50    local resolved51    if [[ "$target" = /* ]]; then52        resolved="$target"53    else54        resolved="${link%/*}/$target"55    fi56    cmux_cua_skill_lexical_normalize "$resolved"57}58 59cmux_cua_skill_canonical_document() {60    local path="$1"61    [[ "$path" = /* ]] || return 162    if [[ -f "$path" ]]; then63        local parent="${path%/*}"64        local basename="${path##*/}"65        local canonical_parent66        canonical_parent="$(cd "$parent" 2>/dev/null && pwd -P)" || canonical_parent=""67        if [[ -n "$canonical_parent" ]]; then68            printf '%s/%s' "$canonical_parent" "$basename"69            return 070        fi71    fi72    cmux_cua_skill_lexical_normalize "$path"73}74 75cmux_cua_skill_frontmatter_name() {76    local file="$1"77    [[ -f "$file" ]] || return 178    local awk_bin=/usr/bin/awk79    [[ -x "$awk_bin" ]] || awk_bin=awk80    "$awk_bin" '81        NR == 1 && $0 ~ /^---[[:space:]]*$/ { in_frontmatter = 1; next }82        in_frontmatter && $0 ~ /^---[[:space:]]*$/ { exit }83        in_frontmatter && $0 ~ /^name:[[:space:]]*/ {84            value = $085            sub(/^name:[[:space:]]*/, "", value)86            gsub(/^[[:space:]]+|[[:space:]]+$/, "", value)87            print value88            exit89        }90    ' "$file" 2>/dev/null91}92 93cmux_cua_skill_name_is() {94    local file="$1"95    local expected="$2"96    local value97    value="$(cmux_cua_skill_frontmatter_name "$file")" || return 198    value="${value#\"}"99    value="${value%\"}"100    value="${value#\'}"101    value="${value%\'}"102    [[ "$value" == "$expected" ]]103}104 105cmux_cua_skill_target_is_managed() {106    # A resource suffix, app name, or dangling path alone is not ownership107    # proof. A link is managed only when its existing bundle has cmux's bundle108    # identifier, lives in a known cmux install/build root, and is owned by109    # root or the current user. Removed bundles have no verifiable owner or110    # identity and are deliberately preserved for manual review.111    local target="$1"112    local resource_name113    case "$target" in114        */Contents/Resources/cmux-cua) resource_name=cmux-cua ;;115        */Contents/Resources/cmux-computer-use) resource_name=cmux-computer-use ;;116        */Contents/Resources/codex-cua) resource_name=codex-cua ;;117        *) return 1 ;;118    esac119 120    local app_bundle="${target%/Contents/Resources/$resource_name}"121    [[ "$app_bundle" == *.app ]] || return 1122    local home="${HOME:-}"123    local app_owner124    app_owner="$(/usr/bin/stat -f '%u' "$app_bundle" 2>/dev/null || true)"125    [[ "$app_owner" == "0" || "$app_owner" == "$(/usr/bin/id -u)" ]] || return 1126 127    case "$app_bundle" in128        /Applications/cmux*.app|/Applications/Utilities/cmux*.app|\129        "$home/Applications"/cmux*.app|\130        "$home/Library/Developer/Xcode/DerivedData"/cmux-*/Build/Products/*/cmux*.app|\131        /tmp/cmux-*/Build/Products/*/cmux*.app)132            ;;133        *)134            return 1135            ;;136    esac137 138    local info_plist="$app_bundle/Contents/Info.plist"139    if [[ -f "$info_plist" && -x /usr/libexec/PlistBuddy ]]; then140        local bundle_id141        bundle_id="$(/usr/libexec/PlistBuddy -c 'Print :CFBundleIdentifier' "$info_plist" 2>/dev/null)" || return 1142        [[ "$bundle_id" == com.cmuxterm.* ]]143        return $?144    fi145    return 1146}147 148cmux_cua_skill_link_is_managed() {149    local link="$1"150    [[ -L "$link" ]] || return 1151    local target resolved152    target="$(cmux_cua_skill_readlink "$link")" || return 1153    [[ -n "$target" ]] || return 1154    resolved="$(cmux_cua_skill_resolve_link_target "$link" "$target")" || resolved="$target"155    cmux_cua_skill_target_is_managed "$resolved" || cmux_cua_skill_target_is_managed "$target"156}157 158cmux_cua_skill_remove_managed_link() {159    local link="$1"160    if cmux_cua_skill_link_is_managed "$link"; then161        # rm acts on the link itself because the target was validated and the162        # operand is an absolute path. Never recurse or follow the target.163        /bin/rm -f "$link" 2>/dev/null || true164        if [[ "${CMUX_CUA_DIAGNOSTICS:-0}" == 1 && ! -L "$link" ]]; then165            printf 'cmux-cua: managed-link-retired path=%q\n' "$link" >&2166        fi167        return 0168    fi169    return 1170}171 172cmux_cua_skill_link_state() {173    local link="$1"174    if cmux_cua_skill_link_is_managed "$link"; then175        printf '%s' managed176    elif [[ -L "$link" || -e "$link" ]]; then177        printf '%s' user178    else179        printf '%s' missing180    fi181}182 183cmux_cua_skill_project_candidate_is_collision() {184    local candidate="$1"185    local source_document="$2"186    [[ -f "$candidate" ]] || return 1187    cmux_cua_skill_name_is "$candidate" cmux-cua || return 1188    local candidate_canonical source_canonical189    candidate_canonical="$(cmux_cua_skill_canonical_document "$candidate")" || return 1190    source_canonical="$(cmux_cua_skill_canonical_document "$source_document")" || source_canonical="$source_document"191    [[ "$candidate_canonical" != "$source_canonical" ]]192}193 194cmux_cua_skill_document_is_user_global() {195    local candidate="$1"196    local provider="$2"197    local home="${HOME:-}"198    local codex_home="${CODEX_HOME:-$home/.codex}"199    local candidate_normalized200    candidate_normalized="$(cmux_cua_skill_lexical_normalize "$candidate" 2>/dev/null)" \201        || candidate_normalized="$candidate"202    local candidate_root_canonical=""203    local candidate_root="${candidate%/cmux-cua/SKILL.md}"204    if [[ -d "$candidate_root" ]]; then205        candidate_root_canonical="$(cd "$candidate_root" 2>/dev/null && pwd -P)"206    fi207 208    local -a global_roots209    if [[ "$provider" == codex ]]; then210        global_roots=("$home/.agents/skills" "$codex_home/skills")211    else212        global_roots=("$home/.claude/skills")213    fi214 215    local global_root global_normalized216    for global_root in "${global_roots[@]}"; do217        [[ "$global_root" = /* ]] || continue218        global_normalized="$(cmux_cua_skill_lexical_normalize "$global_root" 2>/dev/null)" \219            || continue220        if [[ "$candidate_normalized" == "$global_normalized/cmux-cua/SKILL.md" ]]; then221            return 0222        fi223        local global_root_canonical=""224        if [[ -d "$global_root" ]]; then225            global_root_canonical="$(cd "$global_root" 2>/dev/null && pwd -P)"226        fi227        [[ -n "$candidate_root_canonical" \228           && "$candidate_root_canonical" == "$global_root_canonical" ]] \229            && return 0230    done231    return 1232}233 234cmux_cua_skill_project_has_collision() {235    local cwd="$1"236    local provider="$2"237    local source_document="$3"238    [[ "$cwd" = /* ]] || return 1239    local dir240    dir="$(cd "$cwd" 2>/dev/null && pwd -P)" || return 1241    local depth=0242    local candidate243    while [[ "$dir" = /* && $depth -lt 64 ]]; do244        # User-global roots are not project roots. Compare the lexical path245        # before following a candidate symlink so a global link cannot be246        # mistaken for a project collision while walking `~/projects/foo` (or247        # a custom CODEX_HOME nested under another directory).248        if [[ "$provider" == codex ]]; then249            local -a candidates=(250                "$dir/.agents/skills/cmux-cua/SKILL.md"251                "$dir/.codex/skills/cmux-cua/SKILL.md"252            )253            for candidate in "${candidates[@]}"; do254                cmux_cua_skill_document_is_user_global "$candidate" "$provider" && continue255                if cmux_cua_skill_project_candidate_is_collision "$candidate" "$source_document"; then256                    return 0257                fi258            done259        else260            candidate="$dir/.claude/skills/cmux-cua/SKILL.md"261            if ! cmux_cua_skill_document_is_user_global "$candidate" "$provider" \262               && cmux_cua_skill_project_candidate_is_collision "$candidate" "$source_document"; then263                return 0264            fi265        fi266 267        # Match Codex's project-root boundary: once a repository marker is268        # found, do not inspect unrelated parent checkouts.269        [[ -e "$dir/.git" ]] && break270        [[ "$dir" == "/" ]] && break271        dir="${dir%/*}"272        [[ -n "$dir" ]] || dir=/273        depth=$((depth + 1))274    done275    return 1276}277 278cmux_cua_skill_remove_legacy_links() {279    local home="$1"280    local provider="$2"281    local codex_home="${CODEX_HOME:-$home/.codex}"282    local root link name283    if [[ "$provider" == codex ]]; then284        for root in "$home/.agents/skills" "$codex_home/skills"; do285            [[ "$root" = /* ]] || continue286            for name in cmux-computer-use codex-cua; do287                link="$root/$name"288                cmux_cua_skill_remove_managed_link "$link" || true289            done290        done291    else292        # Older Claude wrappers wrote the legacy name into Codex's shared root.293        for root in "$home/.claude/skills" "$home/.agents/skills"; do294            [[ "$root" = /* ]] || continue295            for name in cmux-computer-use codex-cua; do296                link="$root/$name"297                cmux_cua_skill_remove_managed_link "$link" || true298            done299        done300    fi301}302 303cmux_cua_skill_reconcile() {304    local provider="$1"305    local source_dir="$2"306    local cwd="$3"307    local install_requested="$4"308    local home="${HOME:-}"309    [[ "$home" = /* && "$source_dir" = /* ]] || return 1310    local source_document="$source_dir/SKILL.md"311    [[ -f "$source_document" ]] || return 1312 313    local project_collision=0314    if [[ "$install_requested" == 1 ]] \315       && cmux_cua_skill_project_has_collision "$cwd" "$provider" "$source_document"; then316        project_collision=1317    fi318    cmux_cua_skill_remove_legacy_links "$home" "$provider"319 320    local skills_root destination state legacy_root legacy_state321    if [[ "$provider" == codex ]]; then322        skills_root="$home/.agents/skills"323        legacy_root="${CODEX_HOME:-$home/.codex}/skills"324    else325        skills_root="$home/.claude/skills"326        legacy_root=""327    fi328    destination="$skills_root/cmux-cua"329    state="$(cmux_cua_skill_link_state "$destination")"330    local user_path_collision=0331    local blocked_path=""332    if [[ "$state" == user ]]; then333        user_path_collision=1334        blocked_path="$destination"335    fi336    if [[ -n "$legacy_root" && "$legacy_root" != "$skills_root" ]]; then337        legacy_state="$(cmux_cua_skill_link_state "$legacy_root/cmux-cua")"338        if [[ "$legacy_state" == user ]]; then339            user_path_collision=1340            [[ -n "$blocked_path" ]] || blocked_path="$legacy_root/cmux-cua"341        fi342    else343        legacy_state=missing344    fi345 346    if [[ "$install_requested" == 1 && "$user_path_collision" == 1 \347          && "${CMUX_CUA_DIAGNOSTICS:-0}" == 1 ]]; then348        printf 'cmux-cua: skill-install=blocked-user-path path=%q\n' "$blocked_path" >&2349    fi350    if [[ "$install_requested" == 1 && "$project_collision" == 1 \351          && "${CMUX_CUA_DIAGNOSTICS:-0}" == 1 ]]; then352        printf 'cmux-cua: skill-install=blocked-project-collision path=%q\n' "$cwd" >&2353    fi354 355    if [[ "$install_requested" == 1 \356          && "$project_collision" != 1 \357          && "$user_path_collision" != 1 ]]; then358        /bin/mkdir -p "$skills_root" 2>/dev/null || true359        if [[ "$state" == missing ]]; then360            /bin/ln -s "$source_dir" "$destination" 2>/dev/null || true361        elif [[ "$state" == managed ]]; then362            /bin/ln -sfn "$source_dir" "$destination" 2>/dev/null || true363        fi364    elif [[ "$state" == managed ]]; then365        # This is a per-launch preference, not an install receipt. Without366        # opt-in (or beside a project collision), retire only verified367        # app-managed links. Normal user-installed skills are never removed.368        cmux_cua_skill_remove_managed_link "$destination" || true369    fi370    # The deprecated root must not contribute a second managed discovery path,371    # including when the canonical destination has never been installed.372    if [[ "$legacy_state" == managed ]]; then373        cmux_cua_skill_remove_managed_link "$legacy_root/cmux-cua" || true374    fi375    return 0376}377