first commit

scripts/stack_installers/install_rtorrent_rhel.py

@@ -0,0 +1,891 @@
+#!/usr/bin/env python3
+import argparse
+import itertools
+import os
+import pwd
+import re
+import shutil
+import subprocess
+import sys
+import threading
+import time
+from pathlib import Path
+
+DEFAULT_USER = "rtorrent"
+DEFAULT_GROUP = "rtorrent"
+DEFAULT_HOME = "/home/rtorrent"
+DEFAULT_BASE_DIR = "/opt/rtorrent_build"
+DEFAULT_LIBTORRENT_REF = "v0.16.11"
+DEFAULT_RTORRENT_REF = "v0.16.11"
+DEFAULT_XMLRPC_REF = "latest-stable"
+DEFAULT_CARES_REF = "1.34.6"
+DEFAULT_CURL_REF = "8.19.0"
+DEFAULT_SERVICE_PATH = "/etc/systemd/system/rtorrent@.service"
+DEFAULT_SCGI_PORT = 5000
+DEFAULT_TORRENT_PORT = 51300
+
+
+class InstallError(Exception):
+    pass
+
+
+class Spinner:
+    FRAMES = ["|", "/", "-", "\\"]
+
+    def __init__(self, message, enabled=True):
+        self.message = message
+        self.enabled = enabled and sys.stdout.isatty()
+        self._stop = threading.Event()
+        self._thread = None
+        self._start = None
+
+    def _run(self):
+        for frame in itertools.cycle(self.FRAMES):
+            if self._stop.is_set():
+                break
+            elapsed = time.time() - self._start
+            sys.stdout.write(f"\r[ {frame} ] {self.message} ({elapsed:.1f}s)")
+            sys.stdout.flush()
+            time.sleep(0.12)
+
+    def __enter__(self):
+        self._start = time.time()
+        if self.enabled:
+            self._thread = threading.Thread(target=self._run, daemon=True)
+            self._thread.start()
+        return self
+
+    def __exit__(self, exc_type, exc, tb):
+        elapsed = time.time() - self._start
+        if self.enabled:
+            self._stop.set()
+            self._thread.join(timeout=0.5)
+            status = "ERR" if exc else "OK "
+            sys.stdout.write(f"\r[ {status} ] {self.message} ({elapsed:.1f}s)\n")
+            sys.stdout.flush()
+
+
+def build_log_dir():
+    path = Path(os.environ.get("PYTORRENT_STACK_LOG_DIR", "/var/log/pytorrent-installer"))
+    path.mkdir(parents=True, exist_ok=True)
+    return path
+
+
+def tail_file(path, lines=80):
+    try:
+        data = Path(path).read_text(errors="replace").splitlines()
+    except OSError:
+        return ""
+    return "\n".join(data[-lines:])
+
+
+def run(cmd, *, cwd=None, env=None, check=True, debug=False, capture_output=False, log_name=None):
+    if debug:
+        print(f"\n>>> {' '.join(cmd)}")
+    log_path = None
+    log_handle = None
+    if log_name and not capture_output and not debug:
+        safe_name = re.sub(r"[^A-Za-z0-9_.-]+", "_", log_name).strip("_") or "command"
+        log_path = build_log_dir() / f"{safe_name}.log"
+        log_handle = open(log_path, "a", encoding="utf-8")
+        log_handle.write(f"\n>>> {' '.join(cmd)}\n")
+        log_handle.flush()
+    try:
+        stdout = subprocess.PIPE if capture_output else (None if debug else (log_handle or subprocess.DEVNULL))
+        stderr = subprocess.PIPE if capture_output else (None if debug else (subprocess.STDOUT if log_handle else subprocess.DEVNULL))
+        result = subprocess.run(cmd, cwd=cwd, env=env, check=False, text=True, stdout=stdout, stderr=stderr)
+    finally:
+        if log_handle:
+            log_handle.close()
+    if check and result.returncode != 0:
+        stderr_text = ""
+        if capture_output and result.stderr:
+            stderr_text = f"\n{result.stderr.strip()}"
+        if log_path:
+            stderr_text += f"\nBuild log: {log_path}\n--- last log lines ---\n{tail_file(log_path)}"
+        raise InstallError(f"Command failed with exit code {result.returncode}: {' '.join(cmd)}{stderr_text}")
+    return result
+
+
+def capture(cmd, **kwargs):
+    result = run(cmd, capture_output=True, **kwargs)
+    out = (result.stdout or "").strip()
+    err = (result.stderr or "").strip()
+    return out if out else err
+
+
+def require_root():
+    if os.geteuid() != 0:
+        raise InstallError("This script must be run as root (use sudo).")
+
+
+def detect_rhel():
+    os_release = Path("/etc/os-release")
+    if not os_release.exists():
+        raise InstallError("Cannot detect operating system: /etc/os-release is missing.")
+
+    data = {}
+    for line in os_release.read_text().splitlines():
+        if "=" in line:
+            k, v = line.split("=", 1)
+            data[k] = v.strip().strip('"')
+
+    distro_id = data.get("ID", "").lower()
+    distro_like = data.get("ID_LIKE", "").lower()
+    rhel_markers = {"rhel", "centos", "rocky", "almalinux", "fedora", "ol", "scientific"}
+    if distro_id not in rhel_markers and not any(marker in distro_like for marker in ("rhel", "fedora", "centos")):
+        raise InstallError(
+            f"Unsupported distribution: ID={data.get('ID', 'unknown')}, "
+            f"ID_LIKE={data.get('ID_LIKE', 'unknown')}. This installer supports RHEL-compatible systems only."
+        )
+
+    print(f"Detected RHEL-compatible system: {data.get('PRETTY_NAME', distro_id)}")
+
+
+def prompt_yes_no(question, default=True, assume_yes=False):
+    if assume_yes:
+        print(f"{question} [{'Y/n' if default else 'y/N'}] -> auto-yes")
+        return True
+
+    suffix = "[Y/n]" if default else "[y/N]"
+    while True:
+        reply = input(f"{question} {suffix} ").strip().lower()
+        if not reply:
+            return default
+        if reply in {"y", "yes"}:
+            return True
+        if reply in {"n", "no"}:
+            return False
+        print("Please answer yes or no.")
+
+
+def parse_version(version):
+    parts = [int(x) for x in re.findall(r"\d+", version)]
+    return tuple(parts[:3]) if parts else (0,)
+
+
+def enable_rhel_optional_repos(*, debug=False):
+    manager = shutil.which("dnf") or shutil.which("yum")
+    if not manager:
+        return
+    # CRB/PowerTools is required by many EPEL/devel packages on RHEL-compatible systems.
+    crb = shutil.which("crb")
+    if crb:
+        run([crb, "enable"], check=False, debug=debug, log_name="enable_crb")
+    config_manager = shutil.which("dnf") or shutil.which("yum")
+    run([config_manager, "config-manager", "--set-enabled", "crb"], check=False, debug=debug, log_name="enable_crb")
+    run([config_manager, "config-manager", "--set-enabled", "powertools"], check=False, debug=debug, log_name="enable_powertools")
+
+
+def ensure_packages(packages, *, debug=False):
+    manager = shutil.which("dnf") or shutil.which("yum")
+    if not manager:
+        raise InstallError("dnf or yum was not found on this RHEL-compatible system.")
+    print("Installing build and runtime dependencies...")
+    enable_rhel_optional_repos(debug=debug)
+    # RHEL-compatible systems do not provide Debian's build-essential package.
+    # The closest equivalent is the Development Tools group.
+    run([manager, "groupinstall", "-y", "Development Tools"], check=False, debug=debug, log_name="dnf_groupinstall_development_tools")
+    run([manager, "install", "-y", *packages], debug=debug, log_name="dnf_install_rtorrent_deps")
+
+
+def ensure_dir(path, owner=None, group=None, mode=None):
+    Path(path).mkdir(parents=True, exist_ok=True)
+    if owner is not None or group is not None:
+        shutil.chown(path, user=owner, group=group)
+    if mode is not None:
+        os.chmod(path, mode)
+
+
+def create_system_user(user, group, home, assume_yes=False, debug=False):
+    try:
+        pwd.getpwnam(user)
+        print(f"User '{user}' already exists.")
+    except KeyError:
+        if not prompt_yes_no(f"Create system user '{user}' with home '{home}'?", default=True, assume_yes=assume_yes):
+            raise InstallError("User creation declined.")
+        run(["groupadd", "--system", group], check=False, debug=debug)
+        run([
+            "useradd",
+            "--system",
+            "--home-dir", home,
+            "--create-home",
+            "--shell", "/usr/sbin/nologin",
+            "--gid", group,
+            user,
+        ], debug=debug)
+
+
+def clone_or_update_repo(repo_url, repo_dir, ref, *, debug=False):
+    repo_dir = Path(repo_dir)
+    if not repo_dir.exists():
+        with Spinner(f"Cloning {repo_dir.name}", enabled=not debug):
+            run(["git", "clone", repo_url, str(repo_dir)], debug=debug)
+    else:
+        print(f"Repository already exists: {repo_dir}")
+    with Spinner(f"Checking out {repo_dir.name} -> {ref}", enabled=not debug):
+        run(["git", "fetch", "--all", "--tags"], cwd=str(repo_dir), debug=debug)
+        run(["git", "checkout", ref], cwd=str(repo_dir), debug=debug)
+        run(["git", "pull", "--ff-only"], cwd=str(repo_dir), check=False, debug=debug)
+
+
+def download_file(url, destination, *, debug=False):
+    run(["curl", "-fL", url, "-o", str(destination)], debug=debug)
+
+
+def extract_tarball(tarball, destination, *, debug=False):
+    if destination.exists():
+        shutil.rmtree(destination)
+    destination.mkdir(parents=True, exist_ok=True)
+    run(["tar", "-xzf", str(tarball), "-C", str(destination), "--strip-components=1"], debug=debug)
+
+
+def find_xmlrpc_config(base_dir, preferred_install=None):
+    candidates = []
+
+    if preferred_install is not None:
+        preferred = Path(preferred_install) / "bin" / "xmlrpc-c-config"
+        if preferred.exists():
+            candidates.append(preferred.resolve())
+
+    root = Path(base_dir)
+    if root.exists():
+        for match in root.rglob("xmlrpc-c-config"):
+            if match.is_file():
+                candidates.append(match.resolve())
+
+    unique = []
+    seen = set()
+    for candidate in candidates:
+        if candidate not in seen:
+            seen.add(candidate)
+            unique.append(candidate)
+
+    if preferred_install is not None:
+        preferred_prefix = str(Path(preferred_install).resolve())
+        for candidate in unique:
+            if str(candidate).startswith(preferred_prefix):
+                return candidate
+
+    return unique[0] if unique else None
+
+
+def verify_xmlrpc_environment(xmlrpc_config_path, *, debug=False):
+    tool = Path(xmlrpc_config_path)
+    if not tool.exists():
+        raise InstallError(f"xmlrpc-c-config was not found: {tool}")
+    version = capture([str(tool), "--version"], check=True, debug=debug)
+    if parse_version(version) < (1, 11):
+        raise InstallError(f"xmlrpc-c version is too old: {version}. Version 1.11 or newer is required.")
+    print(f"Detected xmlrpc-c version: {version} ({tool})")
+    return version
+
+
+def build_env(*prefixes, extra_env=None):
+    env = os.environ.copy()
+    include_dirs = []
+    lib_dirs = []
+    pkg_dirs = []
+    bin_dirs = []
+
+    for prefix in prefixes:
+        if not prefix:
+            continue
+        prefix = str(prefix)
+        include_dirs.append(f"-I{prefix}/include")
+        lib_dirs.append(f"-L{prefix}/lib")
+        pkg_dirs.append(f"{prefix}/lib/pkgconfig")
+        bin_dirs.append(f"{prefix}/bin")
+
+    if include_dirs:
+        env["CPPFLAGS"] = " ".join(include_dirs + [env.get("CPPFLAGS", "")]).strip()
+        env["CFLAGS"] = " ".join(include_dirs + [env.get("CFLAGS", "")]).strip()
+
+    if lib_dirs:
+        rpaths = [f"-Wl,-rpath,{d[2:]}" for d in lib_dirs]
+        env["LDFLAGS"] = " ".join(lib_dirs + rpaths + [env.get("LDFLAGS", "")]).strip()
+
+    if pkg_dirs:
+        env["PKG_CONFIG_PATH"] = ":".join(pkg_dirs + ([env.get("PKG_CONFIG_PATH")] if env.get("PKG_CONFIG_PATH") else []))
+
+    if bin_dirs:
+        env["PATH"] = ":".join(bin_dirs + [env.get("PATH", "")])
+
+    if extra_env:
+        env.update(extra_env)
+
+    return env
+
+
+def build_xmlrpc_c(base_dir, xmlrpc_ref, *, debug=False):
+    source_root = Path(base_dir) / "xmlrpc-c-src"
+    install_dir = Path(base_dir) / "xmlrpc-c_install"
+    build_root = Path(base_dir) / "_sources"
+    tarball = build_root / "xmlrpc-c.tar.gz"
+
+    existing_config = find_xmlrpc_config(base_dir, install_dir)
+    if existing_config and str(existing_config).startswith(str(install_dir.resolve())):
+        print(f"Reusing existing xmlrpc-c installation: {existing_config}")
+        version = verify_xmlrpc_environment(existing_config, debug=debug)
+        return install_dir, version
+
+    ensure_dir(build_root)
+
+    if xmlrpc_ref == "latest-stable":
+        url = "https://sourceforge.net/projects/xmlrpc-c/files/latest/download"
+    elif re.match(r"^\d+\.\d+\.\d+$", xmlrpc_ref):
+        url = (
+            "https://downloads.sourceforge.net/project/xmlrpc-c/Xmlrpc-c%20Super%20Stable/"
+            f"{xmlrpc_ref}/xmlrpc-c-{xmlrpc_ref}.tgz"
+        )
+    else:
+        url = xmlrpc_ref
+
+    with Spinner("Downloading xmlrpc-c", enabled=not debug):
+        download_file(url, tarball, debug=debug)
+        extract_tarball(tarball, source_root, debug=debug)
+    with Spinner("Configuring xmlrpc-c", enabled=not debug):
+        run(["./configure", f"--prefix={install_dir}"], cwd=str(source_root), debug=debug)
+    with Spinner("Building xmlrpc-c", enabled=not debug):
+        run(["make", "-j", str(os.cpu_count() or 1)], cwd=str(source_root), debug=debug, log_name=f"make_{Path(source_root).name}")
+    with Spinner("Installing xmlrpc-c", enabled=not debug):
+        run(["make", "install"], cwd=str(source_root), debug=debug, log_name=f"make_install_{Path(source_root).name}")
+
+    xmlrpc_config = find_xmlrpc_config(base_dir, install_dir)
+    if not xmlrpc_config or not str(xmlrpc_config).startswith(str(install_dir.resolve())):
+        raise InstallError(f"Custom xmlrpc-c build finished, but xmlrpc-c-config was not found under {install_dir}.")
+    version = verify_xmlrpc_environment(xmlrpc_config, debug=debug)
+    return install_dir, version
+
+
+def build_cares(base_dir, cares_version, *, debug=False):
+    source_root = Path(base_dir) / "c-ares-src"
+    install_dir = Path(base_dir) / "c-ares_install"
+    build_root = Path(base_dir) / "_sources"
+    tarball = build_root / f"c-ares-{cares_version}.tar.gz"
+    url = f"https://github.com/c-ares/c-ares/releases/download/v{cares_version}/c-ares-{cares_version}.tar.gz"
+
+    ensure_dir(build_root)
+    with Spinner("Downloading c-ares", enabled=not debug):
+        download_file(url, tarball, debug=debug)
+        extract_tarball(tarball, source_root, debug=debug)
+    with Spinner("Configuring c-ares", enabled=not debug):
+        run([
+            "cmake",
+            "-S", str(source_root),
+            "-B", str(source_root / "build"),
+            f"-DCMAKE_INSTALL_PREFIX={install_dir}",
+            "-DCARES_SHARED=ON",
+            "-DCARES_STATIC=OFF",
+            "-DCMAKE_BUILD_TYPE=Release",
+        ], debug=debug)
+    with Spinner("Building c-ares", enabled=not debug):
+        run(["cmake", "--build", str(source_root / "build"), "--parallel", str(os.cpu_count() or 1)], debug=debug)
+    with Spinner("Installing c-ares", enabled=not debug):
+        run(["cmake", "--install", str(source_root / "build")], debug=debug)
+    return install_dir, cares_version
+
+
+def build_curl(base_dir, curl_version, cares_install, *, debug=False):
+    source_root = Path(base_dir) / "curl-src"
+    install_dir = Path(base_dir) / "curl_install"
+    build_root = Path(base_dir) / "_sources"
+    tarball = build_root / f"curl-{curl_version}.tar.gz"
+    url = f"https://curl.se/download/curl-{curl_version}.tar.gz"
+
+    ensure_dir(build_root)
+    with Spinner("Downloading curl", enabled=not debug):
+        download_file(url, tarball, debug=debug)
+        extract_tarball(tarball, source_root, debug=debug)
+
+    env = build_env(cares_install)
+    buildconf_script = source_root / "buildconf"
+    with Spinner("Preparing curl build system", enabled=not debug):
+        if buildconf_script.exists():
+            run(["./buildconf"], cwd=str(source_root), env=env, debug=debug)
+        run(["make", "distclean"], cwd=str(source_root), env=env, check=False, debug=debug)
+    with Spinner("Configuring curl with c-ares", enabled=not debug):
+        run([
+            "./configure",
+            f"--prefix={install_dir}",
+            "--with-openssl",
+            f"--enable-ares={cares_install}",
+            "--disable-static",
+            "--enable-shared",
+        ], cwd=str(source_root), env=env, debug=debug)
+    with Spinner("Building curl", enabled=not debug):
+        run(["make", "-j", str(os.cpu_count() or 1)], cwd=str(source_root), env=env, debug=debug, log_name=f"make_{Path(source_root).name}")
+    with Spinner("Installing curl", enabled=not debug):
+        run(["make", "install"], cwd=str(source_root), env=env, debug=debug, log_name=f"make_install_{Path(source_root).name}")
+
+    version = capture([str(install_dir / "bin" / "curl"), "--version"], env=build_env(install_dir, cares_install), debug=debug)
+    return install_dir, version
+
+
+def build_libtorrent(base_dir, libtorrent_ref, curl_install=None, cares_install=None, *, debug=False):
+    source_dir = Path(base_dir) / "libtorrent"
+    install_dir = Path(base_dir) / "libtorrent_install"
+    clone_or_update_repo("https://github.com/rakshasa/libtorrent.git", source_dir, libtorrent_ref, debug=debug)
+
+    prefixes = []
+    if curl_install:
+        prefixes.append(curl_install)
+    if cares_install:
+        prefixes.append(cares_install)
+    env = build_env(*prefixes)
+    configure_cmd = ["./configure", f"--prefix={install_dir}"]
+
+    if curl_install:
+        curl_config = str(Path(curl_install) / "bin" / "curl-config")
+        env["CURL_CONFIG"] = curl_config
+        if Path(curl_config).exists():
+            configure_cmd.append(f"--with-curl={curl_config}")
+        env["LIBS"] = f"-L{Path(curl_install) / 'lib'} -lcurl " + env.get("LIBS", "")
+        if cares_install:
+            env["LIBS"] = f"-L{Path(cares_install) / 'lib'} -lcares " + env.get("LIBS", "")
+
+    with Spinner("Preparing libtorrent build system", enabled=not debug):
+        run(["autoreconf", "-i"], cwd=str(source_dir), env=env, debug=debug)
+        run(["make", "distclean"], cwd=str(source_dir), env=env, check=False, debug=debug)
+    with Spinner("Configuring libtorrent", enabled=not debug):
+        run(configure_cmd, cwd=str(source_dir), env=env, debug=debug)
+    with Spinner("Building libtorrent", enabled=not debug):
+        run(["make", "-j", str(os.cpu_count() or 1)], cwd=str(source_dir), env=env, debug=debug, log_name=f"make_{Path(source_dir).name}")
+    with Spinner("Installing libtorrent", enabled=not debug):
+        run(["make", "install"], cwd=str(source_dir), env=env, debug=debug, log_name=f"make_install_{Path(source_dir).name}")
+
+    version = capture(["git", "describe", "--tags", "--always"], cwd=str(source_dir), debug=debug)
+    return install_dir, version
+
+
+def build_rtorrent(base_dir, rtorrent_ref, libtorrent_install, xmlrpc_install, curl_install=None, cares_install=None, *, debug=False):
+    source_dir = Path(base_dir) / "rtorrent"
+    install_dir = Path(base_dir) / "rtorrent_install"
+
+    clone_or_update_repo("https://github.com/rakshasa/rtorrent.git", source_dir, rtorrent_ref, debug=debug)
+
+    xmlrpc_config = find_xmlrpc_config(base_dir, xmlrpc_install)
+    if not xmlrpc_config:
+        raise InstallError(f"Could not find custom xmlrpc-c-config under {base_dir}.")
+    if not str(xmlrpc_config).startswith(str(Path(xmlrpc_install).resolve())):
+        raise InstallError(f"Wrong xmlrpc-c-config selected: {xmlrpc_config}. Expected one under: {xmlrpc_install}")
+
+    verify_xmlrpc_environment(xmlrpc_config, debug=debug)
+
+    prefixes = [libtorrent_install, xmlrpc_install]
+    if curl_install:
+        prefixes.append(curl_install)
+    if cares_install:
+        prefixes.append(cares_install)
+    env = build_env(*prefixes)
+    env["PATH"] = f"{xmlrpc_config.parent}:" + env.get("PATH", "")
+    env["XMLRPC_C_CONFIG"] = str(xmlrpc_config)
+
+    with Spinner("Preparing rTorrent build system", enabled=not debug):
+        run(["autoreconf", "-i"], cwd=str(source_dir), env=env, debug=debug)
+        run(["make", "distclean"], cwd=str(source_dir), env=env, check=False, debug=debug)
+
+    configure_cmd = ["./configure", f"--prefix={install_dir}", "--with-xmlrpc-c"]
+    with Spinner("Configuring rTorrent", enabled=not debug):
+        run(configure_cmd, cwd=str(source_dir), env=env, debug=debug)
+    with Spinner("Building rTorrent", enabled=not debug):
+        run(["make", "-j", str(os.cpu_count() or 1)], cwd=str(source_dir), env=env, debug=debug, log_name=f"make_{Path(source_dir).name}")
+    with Spinner("Installing rTorrent", enabled=not debug):
+        run(["make", "install"], cwd=str(source_dir), env=env, debug=debug, log_name=f"make_install_{Path(source_dir).name}")
+
+    runtime_prefixes = [libtorrent_install, xmlrpc_install]
+    if curl_install:
+        runtime_prefixes.append(curl_install)
+    if cares_install:
+        runtime_prefixes.append(cares_install)
+    runtime_env = build_env(*runtime_prefixes)
+    runtime_env["LD_LIBRARY_PATH"] = ":".join([f"{p}/lib" for p in runtime_prefixes])
+    version = capture([str(install_dir / "bin" / "rtorrent"), "-h"], env=runtime_env, check=False, debug=debug)
+    return install_dir, version
+
+
+def install_symlinks(rtorrent_install, libtorrent_install, xmlrpc_install, curl_install=None, cares_install=None, *, debug=False):
+    rtorrent_bin = Path(rtorrent_install) / "bin" / "rtorrent"
+    if not rtorrent_bin.exists():
+        raise InstallError(f"Compiled rtorrent binary not found: {rtorrent_bin}")
+
+    usr_local_bin = Path("/usr/local/bin/rtorrent")
+    if usr_local_bin.exists() or usr_local_bin.is_symlink():
+        usr_local_bin.unlink()
+    usr_local_bin.symlink_to(rtorrent_bin)
+    print(f"Symlinked {usr_local_bin} -> {rtorrent_bin}")
+
+    lib_dirs = [f"{libtorrent_install}/lib", f"{xmlrpc_install}/lib"]
+    if curl_install:
+        lib_dirs.append(f"{curl_install}/lib")
+    if cares_install:
+        lib_dirs.append(f"{cares_install}/lib")
+    ld_conf = Path("/etc/ld.so.conf.d/rtorrent-custom-libs.conf")
+    ld_conf.write_text("\n".join(lib_dirs) + "\n")
+    run(["ldconfig"], debug=debug)
+
+
+def write_service(service_path, binary_path, runtime_lib_dirs):
+    service_content = f"""[Unit]
+Description=rTorrent for %I | https://git.linuxiarz.pl/gru/tools_scripts/_edit/master/install_rtorrent.py
+After=network.target
+
+[Service]
+Type=simple
+User=%I
+Group=%I
+KillMode=process
+WorkingDirectory=/home/%I
+ExecStartPre=-/bin/rm -f /home/%I/.session/rtorrent.lock
+ExecStart={binary_path} -o system.daemon.set=true -n -o import=/home/%I/.rtorrent.rc
+KillSignal=SIGTERM
+TimeoutStopSec=300
+Restart=always
+RestartSec=3
+LimitNOFILE=1048576
+Environment=LD_LIBRARY_PATH={runtime_lib_dirs}
+
+[Install]
+WantedBy=multi-user.target
+"""
+    Path(service_path).write_text(service_content)
+    print(f"Wrote systemd unit: {service_path}")
+    run(["systemctl", "daemon-reload"])
+
+
+def extract_version_tuple(text):
+    if not text:
+        return None
+    match = re.search(r"(?:^|[^0-9])(\d+)\.(\d+)\.(\d+)(?:[^0-9]|$)", str(text))
+    if not match:
+        return None
+    return tuple(int(part) for part in match.groups())
+
+
+def rtorrent_bind_address_directive(rtorrent_ref, rtorrent_version=None):
+    version = extract_version_tuple(rtorrent_ref) or extract_version_tuple(rtorrent_version)
+    if version and version < (0, 16, 0):
+        return "network.bind_address.set"
+    return "network.bind_address.ipv4.set"
+
+
+def build_rtorrent_config_content(username, scgi_port, torrent_port, bind_address_directive):
+    return f"""
+## https://git.linuxiarz.pl/gru/tools_scripts/_edit/master/install_rtorrent.py
+# Generated by install_rtorrent.py
+
+directory.default.set = /home/{username}/downloads
+session.path.set = /home/{username}/.session
+encoding.add = UTF-8
+
+network.scgi.open_port = 127.0.0.1:{scgi_port}
+network.port_range.set = {torrent_port}-{torrent_port}
+network.port_random.set = no
+{bind_address_directive} = 0.0.0.0
+
+system.file.allocate.set = 0
+system.umask.set = 0022
+
+dht.mode.set = disable
+protocol.pex.set = no
+trackers.use_udp.set = no
+protocol.encryption.set = allow_incoming,enable_retry,prefer_plaintext
+
+#schedule2 = tied_directory,6,5,start_tied=
+#schedule2 = untied_directory,7,5,stop_untied=
+schedule2 = session_save,300,300,((session.save))
+schedule2 = watch_directory,60,60,load.normal=/home/{username}/watch/*.torrent
+
+ratio.max.set = -1
+network.xmlrpc.size_limit.set = 33554432
+network.http.max_open.set = 64
+network.max_open_sockets.set = 8192
+network.max_open_files.set = 32768
+network.http.dns_cache_timeout.set = 0
+#pieces.memory.max.set = 1800M
+""".lstrip()
+
+
+def write_rtorrent_config(user_home, username, scgi_port, torrent_port, bind_address_directive, *, force_config=False):
+    config_path = Path(user_home) / ".rtorrent.rc"
+    config_content = build_rtorrent_config_content(username, scgi_port, torrent_port, bind_address_directive)
+
+    if config_path.exists() and not force_config:
+        print(f"Config already exists: {config_path}")
+        print("Not overwriting existing config. Proposed generated config would be:")
+        print("--- BEGIN PROPOSED .rtorrent.rc ---")
+        print(config_content, end="")
+        print("--- END PROPOSED .rtorrent.rc ---")
+        print("Use --force-config to overwrite the existing config.")
+        return False
+
+    config_path.write_text(config_content)
+    shutil.chown(config_path, user=username, group=username)
+    print(f"Wrote config: {config_path}")
+    return True
+
+
+def prepare_user_dirs(user_home, username):
+    for d in [Path(user_home) / "downloads", Path(user_home) / ".session", Path(user_home) / "watch"]:
+        ensure_dir(d, owner=username, group=username, mode=0o755)
+    shutil.chown(Path(user_home), user=username, group=username)
+
+
+def enable_service(user, *, debug=False):
+    unit_name = f"rtorrent@{user}.service"
+    run(["systemctl", "enable", "--now", unit_name], debug=debug)
+    print(f"Enabled and started {unit_name}")
+
+
+def print_link_lines(title, lines):
+    print(title)
+    for line in lines:
+        print(line)
+
+
+def print_optional_libs_explanation():
+    print("Optional libraries:")
+    print("  - c-ares: asynchronous DNS resolver. It helps avoid blocking DNS lookups and can improve tracker/DHT-heavy workloads when curl is built with AsynchDNS support.")
+    print("  - curl: HTTP/HTTPS transfer library used by libtorrent for tracker/web requests. Building a fresh curl can provide newer TLS/HTTP fixes and c-ares based async DNS.")
+    print("  - minimal build: builds only xmlrpc-c, libtorrent and rTorrent; it uses the system libraries already available on Debian.")
+
+
+def resolve_optional_build_mode(args):
+    requested = [name for name, enabled in [
+        ("--minimal", args.minimal),
+        ("--with-cares", args.with_cares),
+        ("--with-curl", args.with_curl),
+        ("--no-cares", args.no_cares),
+        ("--no-curl", args.no_curl),
+    ] if enabled]
+
+    if args.minimal and (args.with_cares or args.with_curl):
+        raise InstallError("Conflicting options: --minimal cannot be used with --with-cares or --with-curl.")
+    if args.no_curl and args.with_curl:
+        raise InstallError("Conflicting options: --no-curl cannot be used with --with-curl.")
+    if args.no_cares and (args.with_cares or args.with_curl):
+        raise InstallError("Conflicting options: --no-cares cannot be used with --with-cares or --with-curl.")
+
+    if args.minimal or args.no_curl:
+        return False
+    if args.with_curl or args.with_cares:
+        return True
+    if args.no_cares:
+        return False
+
+    if args.yes:
+        return False
+
+    print_optional_libs_explanation()
+    return prompt_yes_no(
+        "Build additional c-ares and newest custom curl?",
+        default=False,
+        assume_yes=False,
+    )
+
+
+def verify_libtorrent_curl_integration(base_dir, libtorrent_install, curl_install, cares_install, *, debug=False):
+    libtorrent_so = next((p for p in sorted((Path(libtorrent_install) / "lib").glob("libtorrent.so*")) if p.is_file() and not p.is_symlink()), None)
+    if not libtorrent_so:
+        raise InstallError("Could not find compiled libtorrent shared object for verification.")
+
+    libtorrent_linked = capture(["ldd", str(libtorrent_so)], check=True, debug=debug)
+    curl_lines = [line for line in libtorrent_linked.splitlines() if "libcurl" in line.lower()]
+    print_link_lines("Linked libcurl lines (from libtorrent):", curl_lines)
+
+    expected_curl = str(Path(curl_install) / "lib")
+    if curl_lines:
+        if not any(expected_curl in line for line in curl_lines):
+            raise InstallError(f"libtorrent does not appear to be linked against the compiled libcurl from {expected_curl}.")
+    else:
+        config_log = Path(base_dir) / "libtorrent" / "config.log"
+        config_text = config_log.read_text(errors="ignore") if config_log.exists() else ""
+        curl_config = str(Path(curl_install) / "bin" / "curl-config")
+        if curl_config not in config_text and expected_curl not in config_text:
+            raise InstallError(
+                "libtorrent does not expose libcurl in ldd, and config.log does not show the custom curl path either. "
+                "The build likely used the system curl or no curl integration."
+            )
+        print("libtorrent does not show libcurl in ldd; accepting config.log evidence of custom curl usage.")
+
+    custom_curl = Path(curl_install) / "bin" / "curl"
+    curl_version = capture([str(custom_curl), "--version"], env=build_env(curl_install, cares_install), check=True, debug=debug)
+    print("Custom curl version:")
+    print(curl_version.splitlines()[0])
+    lower = curl_version.lower()
+    if "asynchdns" not in lower:
+        raise InstallError("Custom curl does not report AsynchDNS support.")
+    if "c-ares" not in lower and "ares" not in lower:
+        print("Warning: curl --version does not explicitly show c-ares. Continuing because AsynchDNS is present.")
+
+    if cares_install:
+        cares_lines = [line for line in libtorrent_linked.splitlines() if "cares" in line.lower()]
+        print_link_lines("Linked c-ares lines (from libtorrent):", cares_lines)
+        if not cares_lines:
+            print("c-ares is not visible in libtorrent ldd; this can still be valid when libcurl is resolved differently.")
+
+
+def verify_install(base_dir, rtorrent_install, libtorrent_install, xmlrpc_install, curl_install=None, cares_install=None, *, debug=False):
+    rtorrent_bin = Path(rtorrent_install) / "bin" / "rtorrent"
+    which_rtorrent = capture(["which", "rtorrent"], check=False, debug=debug) or "not found in PATH"
+    print(f"Resolved rtorrent from PATH: {which_rtorrent}")
+
+    linked = capture(["ldd", str(rtorrent_bin)], check=True, debug=debug)
+    for libname, expected in [("libtorrent", str(Path(libtorrent_install) / "lib")), ("xmlrpc", str(Path(xmlrpc_install) / "lib"))]:
+        lines = [line for line in linked.splitlines() if libname in line]
+        print_link_lines(f"Linked {libname} lines:", lines)
+        if not any(expected in line for line in lines):
+            raise InstallError(f"rtorrent does not appear to be linked against the compiled {libname} from {expected}.")
+
+    if curl_install:
+        verify_libtorrent_curl_integration(base_dir, libtorrent_install, curl_install, cares_install, debug=debug)
+
+    env = build_env(libtorrent_install, xmlrpc_install, curl_install, cares_install)
+    env["LANG"] = "C"
+    env["LC_ALL"] = "C"
+    env["TERM"] = env.get("TERM", "xterm")
+    ld_paths = [str(Path(libtorrent_install) / "lib"), str(Path(xmlrpc_install) / "lib")]
+    if curl_install:
+        ld_paths.append(str(Path(curl_install) / "lib"))
+    if cares_install:
+        ld_paths.append(str(Path(cares_install) / "lib"))
+    env["LD_LIBRARY_PATH"] = ":".join(ld_paths)
+
+    probe = subprocess.run([str(rtorrent_bin), "-h"], env=env, check=False, text=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+    help_output = ((probe.stdout or "") + "\n" + (probe.stderr or "")).lower()
+    if "xmlrpc-c" in help_output and "i8" in help_output:
+        raise InstallError(
+            "rTorrent was built against an xmlrpc-c library without i8 support. "
+            "Make sure the custom xmlrpc-c build is used and that no older local installation shadows it."
+        )
+
+
+def build_parser():
+    parser = argparse.ArgumentParser(description="RHEL-compatible installer for xmlrpc-c + libtorrent + rTorrent under /opt with optional c-ares/custom curl support.")
+    parser.add_argument("--base-dir", default=DEFAULT_BASE_DIR, help=f"Base build/install directory (default: {DEFAULT_BASE_DIR})")
+    parser.add_argument("--libtorrent-ref", default=DEFAULT_LIBTORRENT_REF, help=f"Git branch, tag or commit for libtorrent (default: {DEFAULT_LIBTORRENT_REF})")
+    parser.add_argument("--rtorrent-ref", default=DEFAULT_RTORRENT_REF, help=f"Git branch, tag or commit for rtorrent (default: {DEFAULT_RTORRENT_REF})")
+    parser.add_argument("--xmlrpc-ref", default=DEFAULT_XMLRPC_REF, help="xmlrpc-c source version or URL (default: latest-stable)")
+    parser.add_argument("--cares-ref", default=DEFAULT_CARES_REF, help=f"c-ares release version (default: {DEFAULT_CARES_REF})")
+    parser.add_argument("--curl-ref", default=DEFAULT_CURL_REF, help=f"curl release version (default: {DEFAULT_CURL_REF})")
+    parser.add_argument("--user", default=DEFAULT_USER, help=f"System user for the service (default: {DEFAULT_USER})")
+    parser.add_argument("--group", default=DEFAULT_GROUP, help=f"System group for the service (default: {DEFAULT_GROUP})")
+    parser.add_argument("--home", default=DEFAULT_HOME, help=f"Home directory for the service user (default: {DEFAULT_HOME})")
+    parser.add_argument("--scgi-port", type=int, default=DEFAULT_SCGI_PORT, help=f"SCGI listen port for rTorrent XMLRPC/SCGI (default: {DEFAULT_SCGI_PORT})")
+    parser.add_argument("--torrent-port", type=int, default=DEFAULT_TORRENT_PORT, help=f"Incoming BitTorrent listen port (default: {DEFAULT_TORRENT_PORT})")
+    parser.add_argument("--force-config", action="store_true", help="Overwrite existing ~/.rtorrent.rc. By default, existing config is left unchanged and the proposed changes are printed.")
+    parser.add_argument("--only-build", action="store_true", help="Only build and install libtorrent/rTorrent under /opt. Skip user, config and systemd.")
+    parser.add_argument("--yes", action="store_true", help="Assume yes for interactive prompts; optional c-ares/curl remain disabled unless --with-curl or --with-cares is used.")
+    parser.add_argument("--debug", action="store_true", help="Show full command output during build steps.")
+    parser.add_argument("--minimal", "--core-only", action="store_true", help="Build only xmlrpc-c, libtorrent and rTorrent. Do not build c-ares or custom curl.")
+    parser.add_argument("--no-cares", "--without-cares", dest="no_cares", action="store_true", help="Do not build c-ares. This also disables custom curl integration.")
+    parser.add_argument("--no-curl", "--without-curl", dest="no_curl", action="store_true", help="Do not build custom curl. Implies no c-ares integration for libtorrent.")
+    parser.add_argument("--with-cares", action="store_true", help="Build c-ares and custom curl with asynchronous DNS support.")
+    parser.add_argument("--with-curl", action="store_true", help="Build newest custom curl; c-ares is enabled unless --no-cares is used.")
+    return parser
+
+
+def main():
+    parser = build_parser()
+    args = parser.parse_args()
+    args.use_cares = resolve_optional_build_mode(args)
+
+    require_root()
+    detect_rhel()
+
+    packages = [
+        "gcc", "gcc-c++", "make", "pkgconf-pkg-config", "libtool", "autoconf", "automake", "git", "ca-certificates",
+        "openssl-devel", "ncurses-devel", "expat-devel", "curl", "libcurl-devel", "tar", "gzip", "zlib-devel", "which",
+        "patch", "diffutils", "findutils", "file", "redhat-rpm-config", "libstdc++-devel"
+    ]
+    if args.use_cares:
+        packages.extend(["cmake", "libpsl-devel", "brotli-devel", "libzstd-devel"])
+
+    print("This script will:")
+    print(f"  - build xmlrpc-c from '{args.xmlrpc_ref}'")
+    print(f"  - build libtorrent from '{args.libtorrent_ref}'")
+    print(f"  - build rtorrent from '{args.rtorrent_ref}'")
+    if args.use_cares:
+        print(f"  - build c-ares from '{args.cares_ref}'")
+        print(f"  - build curl from '{args.curl_ref}' with c-ares")
+        print("  - benefit: async DNS via c-ares and newer curl for HTTP/HTTPS tracker requests")
+    else:
+        print("  - minimal build: skip c-ares/custom curl")
+        print("  - build only xmlrpc-c, libtorrent and rTorrent; use RHEL system libraries")
+    print(f"  - install everything under '{args.base_dir}'")
+    if args.only_build:
+        print("  - skip service user, config and systemd setup")
+    else:
+        print(f"  - configure systemd service for user '{args.user}'")
+        print(f"  - use SCGI port {args.scgi_port} and torrent port {args.torrent_port}")
+
+    if not prompt_yes_no("Continue?", default=True, assume_yes=args.yes):
+        print("Aborted by user.")
+        return 1
+
+    ensure_packages(packages, debug=args.debug)
+    ensure_dir(args.base_dir)
+
+    xmlrpc_install, xmlrpc_version = build_xmlrpc_c(args.base_dir, args.xmlrpc_ref, debug=args.debug)
+
+    cares_install = None
+    cares_version = None
+    curl_install = None
+    curl_version = None
+
+    if args.use_cares:
+        cares_install, cares_version = build_cares(args.base_dir, args.cares_ref, debug=args.debug)
+        curl_install, curl_version = build_curl(args.base_dir, args.curl_ref, cares_install, debug=args.debug)
+
+    libtorrent_install, libtorrent_version = build_libtorrent(
+        args.base_dir, args.libtorrent_ref, curl_install=curl_install, cares_install=cares_install, debug=args.debug
+    )
+    rtorrent_install, rtorrent_version = build_rtorrent(
+        args.base_dir, args.rtorrent_ref, libtorrent_install, xmlrpc_install, curl_install=curl_install,
+        cares_install=cares_install, debug=args.debug
+    )
+
+    install_symlinks(rtorrent_install, libtorrent_install, xmlrpc_install, curl_install=curl_install, cares_install=cares_install, debug=args.debug)
+    verify_install(args.base_dir, rtorrent_install, libtorrent_install, xmlrpc_install, curl_install=curl_install, cares_install=cares_install, debug=args.debug)
+
+    if not args.only_build:
+        create_system_user(args.user, args.group, args.home, assume_yes=args.yes, debug=args.debug)
+        prepare_user_dirs(args.home, args.user)
+        bind_address_directive = rtorrent_bind_address_directive(args.rtorrent_ref, rtorrent_version)
+        print(f"Using rTorrent bind address directive: {bind_address_directive}")
+        write_rtorrent_config(args.home, args.user, args.scgi_port, args.torrent_port, bind_address_directive, force_config=args.force_config)
+        runtime_lib_dirs = [f"{libtorrent_install}/lib", f"{xmlrpc_install}/lib"]
+        if curl_install:
+            runtime_lib_dirs.append(f"{curl_install}/lib")
+        if cares_install:
+            runtime_lib_dirs.append(f"{cares_install}/lib")
+        write_service(DEFAULT_SERVICE_PATH, "/usr/local/bin/rtorrent", ":".join(runtime_lib_dirs))
+        enable_service(args.user, debug=args.debug)
+        print(f"\nService status hint: systemctl status rtorrent@{args.user}.service")
+
+    print("\nBuild summary")
+    print("-------------")
+    print(f"xmlrpc-c:   {xmlrpc_version}")
+    print(f"libtorrent: {libtorrent_version}")
+    print(f"rtorrent:   {rtorrent_version.splitlines()[0] if rtorrent_version else args.rtorrent_ref}")
+    if args.use_cares:
+        print(f"c-ares:     {cares_version}")
+        print(f"curl:       {curl_version.splitlines()[0] if curl_version else args.curl_ref}")
+    else:
+        print("c-ares:     disabled")
+        print("curl:       system")
+    print("binary:     /usr/local/bin/rtorrent")
+    print(f"base dir:   {args.base_dir}")
+    print("\nDone.")
+    return 0
+
+
+if __name__ == "__main__":
+    try:
+        sys.exit(main())
+    except KeyboardInterrupt:
+        print("\nInterrupted.")
+        sys.exit(130)
+    except InstallError as exc:
+        print(f"\nERROR: {exc}", file=sys.stderr)
+        sys.exit(1)