[Init] Initial commit - NetMesh terminal manager

electron/bridges/sshInteractiveShells.cjs

@@ -0,0 +1,105 @@
+"use strict";
+
+const { executeBoundedSshCommand } = require("./boundedSshExec.cjs");
+const { isSshChannelOpenRateLimitedError } = require("./boundedSshChannelOpen.cjs");
+
+const SCAN_COMPLETE_MARKER = "__NETCATTY_SHELL_SCAN_COMPLETE__";
+const discoveryDisabledConnections = new WeakSet();
+
+function buildInteractiveShellPidCommand(quoteShellArg) {
+  const script = `SELF=$$
+ps_output=$(ps -e -o pid=,ppid=,tty=,comm=,etimes= 2>/dev/null) || ps_output=$(ps -e -o pid=,ppid=,tty=,comm= 2>/dev/null) || exit 69
+{
+  printf '%s\n' "$ps_output" | awk -v pp="$PPID" -v self="$SELF" '
+    function isshell(c) { sub(/^.*\\//, "", c); sub(/^-/, "", c); return c ~ /^(ba|z|fi|k|da|a|c|tc)?sh$/ }
+    $1 != self && $2 == pp && $3 !~ /^\\?+$/ && isshell($4) {
+      if (NF >= 5 && $5 ~ /^[0-9]+$/) print $1, $5+0
+      else print $1
+    }
+  '
+  if [ -r /proc/$SELF/environ ]; then
+    conn=$(tr '\\0' '\\n' < /proc/$SELF/environ 2>/dev/null | sed -n 's/^SSH_CONNECTION=//p' | head -n1)
+    if [ -n "$conn" ]; then
+      for d in /proc/[0-9]*; do
+        pid=$(basename "$d")
+        [ "$pid" = "$SELF" ] && continue
+        [ -r "$d/environ" ] || continue
+        conn2=$(tr '\\0' '\\n' < "$d/environ" 2>/dev/null | sed -n 's/^SSH_CONNECTION=//p' | head -n1)
+        [ "$conn2" = "$conn" ] || continue
+        comm=$(cat "$d/comm" 2>/dev/null)
+        case "$comm" in sh|bash|zsh|fish|ksh|dash|ash|csh|tcsh) ;; *) continue ;; esac
+        ppid=$(awk '{ print $4 }' "$d/stat" 2>/dev/null)
+        pcomm=$(cat "/proc/$ppid/comm" 2>/dev/null)
+        case "$pcomm" in sshd|dropbear|dropbearmulti) ;; *) continue ;; esac
+        tty=$(ps -p "$pid" -o tty= 2>/dev/null | tr -d '[:space:]')
+        [ -n "$tty" ] && [ "$tty" != "?" ] || continue
+        etimes=$(ps -p "$pid" -o etimes= 2>/dev/null | tr -d '[:space:]')
+        case "$etimes" in
+          ''|*[!0-9]*) printf '%s\\n' "$pid" ;;
+          *) printf '%s %s\\n' "$pid" "$etimes" ;;
+        esac
+      done
+    fi
+  fi
+} | awk '/^[0-9]+/ && !seen[$1]++ { print }'
+printf '%s\n' '${SCAN_COMPLETE_MARKER}'`;
+  return `exec sh -c ${quoteShellArg(script)}`;
+}
+
+async function listInteractiveShellPids(conn, options = {}) {
+  if (!conn || typeof conn.exec !== "function" || typeof options.quoteShellArg !== "function") {
+    return { available: false, pids: [], ages: {} };
+  }
+  const invalidateOnOpenTimeout = options.invalidateOnOpenTimeout === true;
+  if (!invalidateOnOpenTimeout && discoveryDisabledConnections.has(conn)) {
+    return { available: false, disabled: true, pids: [], ages: {} };
+  }
+  // Shell PID discovery only improves cwd recovery for reused shells. A slow
+  // auxiliary exec open must not invalidate the physical transport and close
+  // every interactive shell sharing it. After one open timeout, stop probing
+  // this connection so ssh2 cannot retain another uncancellable callback on
+  // every later reuse.
+  try {
+    const result = await executeBoundedSshCommand(
+      conn,
+      buildInteractiveShellPidCommand(options.quoteShellArg),
+      {
+        openingTimeoutMs: options.openingTimeoutMs ?? 1500,
+        runTimeoutMs: options.runTimeoutMs ?? 1500,
+        maxOutputBytes: 1024 * 1024,
+        setTimeoutFn: options.setTimeoutFn,
+        clearTimeoutFn: options.clearTimeoutFn,
+        invalidateOnOpenTimeout,
+      },
+    );
+    const lines = result.stdout.split(/\r?\n/);
+    const available = lines.includes(SCAN_COMPLETE_MARKER)
+      && (result.code === null || result.code === 0);
+    const pids = [];
+    const ages = {};
+    if (available) {
+      for (const line of lines) {
+        const match = /^(\d+)(?:\s+(\d+))?$/.exec(String(line || "").trim());
+        if (!match) continue;
+        const pid = match[1];
+        if (!pids.includes(pid)) pids.push(pid);
+        if (match[2] !== undefined) ages[pid] = Number(match[2]);
+      }
+    }
+    return { available, pids, ages };
+  } catch (error) {
+    const openTimedOut = error?.code === "SSH_EXEC_OPEN_TIMEOUT";
+    if (openTimedOut && !invalidateOnOpenTimeout) {
+      discoveryDisabledConnections.add(conn);
+    }
+    return {
+      available: false,
+      rateLimited: isSshChannelOpenRateLimitedError(error),
+      openTimedOut,
+      pids: [],
+      ages: {},
+    };
+  }
+}
+
+module.exports = { buildInteractiveShellPidCommand, listInteractiveShellPids };