gstreamer/gst-env.py

#!/usr/bin/env python3

import argparse
import glob
import json
import os
import platform
import re
import shlex
import shutil
import subprocess
import tempfile
import pathlib
import signal
from functools import lru_cache
from pathlib import PurePath, Path
from sys import exit

from typing import Any

from scripts.common import get_meson
from scripts.common import git
from scripts.common import win32_get_short_path_name
from scripts.common import get_wine_shortpath

SCRIPTDIR = os.path.dirname(os.path.realpath(__file__))
PREFIX_DIR = os.path.join(SCRIPTDIR, 'prefix')
# Look for the following build dirs: `build` `_build` `builddir`
DEFAULT_BUILDDIR = os.path.join(SCRIPTDIR, 'build')
if not os.path.exists(DEFAULT_BUILDDIR):
    DEFAULT_BUILDDIR = os.path.join(SCRIPTDIR, '_build')
if not os.path.exists(DEFAULT_BUILDDIR):
    DEFAULT_BUILDDIR = os.path.join(SCRIPTDIR, 'builddir')

TYPELIB_REG = re.compile(r'.*\.typelib$')
SHAREDLIB_REG = re.compile(r'\.so|\.dylib|\.dll')

# libdir is expanded from option of the same name listed in the `meson
# introspect --buildoptions` output.
GSTPLUGIN_FILEPATH_REG_TEMPLATE = r'.*/{libdir}/gstreamer-1.0/[^/]+$'
GSTPLUGIN_FILEPATH_REG = None

BC_RC = '''
BASH_COMPLETION_SCRIPTS="{bash_completions}"
BASH_COMPLETION_PATHS="{bash_completions_paths}"
for p in $BASH_COMPLETION_PATHS; do
for f in $BASH_COMPLETION_SCRIPTS; do
  [ -f "$p/$f" ] && . "$p/$f"
done
done
'''
BASH_COMPLETION_PATHS = [SCRIPTDIR + '/subprojects/gstreamer/data/bash-completion/completions']
BASH_COMPLETION_PATHS += [SCRIPTDIR + '/subprojects/gst-devtools/validate/data/bash-completion/completions']


def str_to_bool(value: Any) -> bool:
    """Return whether the provided string (or any value really) represents true. Otherwise false.
    Just like plugin server stringToBoolean.
    """
    if not value:
        return False
    return str(value).lower() in ("y", "yes", "t", "true", "on", "1")


def listify(o):
    if isinstance(o, str):
        return [o]
    if isinstance(o, list):
        return o
    raise AssertionError('Object {!r} must be a string or a list'.format(o))


def stringify(o):
    if isinstance(o, str):
        return o
    if isinstance(o, list):
        if len(o) == 1:
            return o[0]
        raise AssertionError('Did not expect object {!r} to have more than one element'.format(o))
    raise AssertionError('Object {!r} must be a string or a list'.format(o))


def prepend_env_var(env, var, value, sysroot):
    if var is None:
        return
    if value.startswith(sysroot):
        value = value[len(sysroot):]
    # Try not to exceed maximum length limits for env vars on Windows
    if os.name == 'nt':
        value = win32_get_short_path_name(value)
    env_val = env.get(var, '')
    val = os.pathsep + value + os.pathsep
    # Don't add the same value twice
    if val in env_val or env_val.startswith(value + os.pathsep):
        return
    env[var] = val + env_val
    env[var] = env[var].replace(os.pathsep + os.pathsep, os.pathsep).strip(os.pathsep)


def get_target_install_filename(target, filename):
    '''
    Checks whether this file is one of the files installed by the target
    '''
    basename = os.path.basename(filename)
    for install_filename in listify(target['install_filename']):
        if install_filename.endswith(basename):
            return install_filename
    return None


def get_pkgconfig_variable_from_pcfile(pcfile, varname):
    variables = {}
    substre = re.compile('\$\{[^${}]+\}')
    with pcfile.open('r', encoding='utf-8') as f:
        for line in f:
            if '=' not in line:
                continue
            key, value = line[:-1].split('=', 1)
            subst = {}
            for each in substre.findall(value):
                substkey = each[2:-1]
                subst[each] = variables.get(substkey, '')
            for k, v in subst.items():
                value = value.replace(k, v)
            variables[key] = value
    return variables.get(varname, '')


@lru_cache()
def get_pkgconfig_variable(builddir, pcname, varname):
    '''
    Parsing isn't perfect, but it's good enough.
    '''
    pcfile = Path(builddir) / 'meson-private' / (pcname + '.pc')
    if pcfile.is_file():
        return get_pkgconfig_variable_from_pcfile(pcfile, varname)
    return subprocess.check_output(['pkg-config', pcname, '--variable=' + varname],
                                   universal_newlines=True, encoding='utf-8')


def is_gio_module(target, filename, builddir):
    if target['type'] != 'shared module':
        return False
    install_filename = get_target_install_filename(target, filename)
    if not install_filename:
        return False
    giomoduledir = PurePath(get_pkgconfig_variable(builddir, 'gio-2.0', 'giomoduledir'))
    fpath = PurePath(install_filename)
    if fpath.parent != giomoduledir:
        return False
    return True


def is_library_target_and_not_plugin(target, filename):
    '''
    Don't add plugins to PATH/LD_LIBRARY_PATH because:
    1. We don't need to
    2. It causes us to exceed the PATH length limit on Windows and Wine
    '''
    if target['type'] != 'shared library':
        return False
    # Check if this output of that target is a shared library
    if not SHAREDLIB_REG.search(filename):
        return False
    # Check if it's installed to the gstreamer plugin location
    install_filename = get_target_install_filename(target, filename)
    if not install_filename:
        return False
    global GSTPLUGIN_FILEPATH_REG
    if GSTPLUGIN_FILEPATH_REG is None:
        GSTPLUGIN_FILEPATH_REG = re.compile(GSTPLUGIN_FILEPATH_REG_TEMPLATE)
    if GSTPLUGIN_FILEPATH_REG.search(install_filename.replace('\\', '/')):
        return False
    return True


def is_binary_target_and_in_path(target, filename, bindir):
    if target['type'] != 'executable':
        return False
    # Check if this file installed by this target is installed to bindir
    install_filename = get_target_install_filename(target, filename)
    if not install_filename:
        return False
    fpath = PurePath(install_filename)
    if fpath.parent != bindir:
        return False
    return True


def get_wine_subprocess_env(options, env):
    with open(os.path.join(options.builddir, 'meson-info', 'intro-buildoptions.json')) as f:
        buildoptions = json.load(f)

    prefix, = [o for o in buildoptions if o['name'] == 'prefix']
    path = os.path.normpath(os.path.join(prefix['value'], 'bin'))
    prepend_env_var(env, "PATH", path, options.sysroot)
    wine_path = get_wine_shortpath(
        options.wine.split(' '),
        [path] + env.get('WINEPATH', '').split(';')
    )
    if options.winepath:
        wine_path += ';' + options.winepath
    env['WINEPATH'] = wine_path
    env['WINEDEBUG'] = 'fixme-all'

    return env


def setup_gdb(options):
    python_paths = set()

    if not shutil.which('gdb'):
        return python_paths

    bdir = pathlib.Path(options.builddir).resolve()
    for libpath, gdb_path in [
            (os.path.join("subprojects", "gstreamer", "gst"),
             os.path.join("subprojects", "gstreamer", "libs", "gst", "helpers")),
            (os.path.join("subprojects", "glib", "gobject"), None),
            (os.path.join("subprojects", "glib", "glib"), None)]:

        if not gdb_path:
            gdb_path = libpath

        autoload_path = (pathlib.Path(bdir) / 'gdb-auto-load').joinpath(*bdir.parts[1:]) / libpath
        autoload_path.mkdir(parents=True, exist_ok=True)
        for gdb_helper in glob.glob(str(bdir / gdb_path / "*-gdb.py")):
            python_paths.add(str(bdir / gdb_path))
            python_paths.add(os.path.join(options.srcdir, gdb_path))
            try:
                if os.name == 'nt':
                    shutil.copy(gdb_helper, str(autoload_path / os.path.basename(gdb_helper)))
                else:
                    os.symlink(gdb_helper, str(autoload_path / os.path.basename(gdb_helper)))
            except (FileExistsError, shutil.SameFileError):
                pass

    gdbinit_line = 'add-auto-load-scripts-directory {}\n'.format(bdir / 'gdb-auto-load')
    try:
        with open(os.path.join(options.srcdir, '.gdbinit'), 'r') as f:
            if gdbinit_line in f.readlines():
                return python_paths
    except FileNotFoundError:
        pass

    with open(os.path.join(options.srcdir, '.gdbinit'), 'a') as f:
        f.write(gdbinit_line)

    return python_paths


def is_bash_completion_available(options):
    return os.path.exists(os.path.join(options.builddir, 'subprojects/gstreamer/data/bash-completion/helpers/gst'))


def get_subprocess_env(options, gst_version):
    env = os.environ.copy()

    env["CURRENT_GST"] = os.path.normpath(SCRIPTDIR)
    env["GST_VERSION"] = gst_version
    prepend_env_var(env, "GST_VALIDATE_SCENARIOS_PATH", os.path.normpath(
        "%s/subprojects/gst-devtools/validate/data/scenarios" % SCRIPTDIR),
        options.sysroot)
    env["GST_VALIDATE_PLUGIN_PATH"] = os.path.normpath(
        "%s/subprojects/gst-devtools/validate/plugins" % options.builddir)
    prepend_env_var(env, "GST_VALIDATE_APPS_DIR", os.path.normpath(
        "%s/subprojects/gst-editing-services/tests/validate" % SCRIPTDIR),
        options.sysroot)
    env["GST_ENV"] = gst_version
    env["GST_REGISTRY"] = os.path.normpath(options.builddir + "/registry.dat")
    prepend_env_var(env, "PATH", os.path.normpath(
        "%s/subprojects/gst-devtools/validate/tools" % options.builddir),
        options.sysroot)

    prepend_env_var(env, "GST_VALIDATE_SCENARIOS_PATH", os.path.normpath(
        "%s/subprojects/gst-examples/webrtc/check/validate/scenarios" %
        SCRIPTDIR), options.sysroot)
    prepend_env_var(env, "GST_VALIDATE_APPS_DIR", os.path.normpath(
        "%s/subprojects/gst-examples/webrtc/check/validate/apps" %
        SCRIPTDIR), options.sysroot)

    if options.wine:
        return get_wine_subprocess_env(options, env)

    prepend_env_var(env, "PATH", os.path.join(SCRIPTDIR, 'meson'),
        options.sysroot)

    env["GST_PLUGIN_SYSTEM_PATH"] = ""
    env["GST_PLUGIN_SCANNER"] = os.path.normpath(
        "%s/subprojects/gstreamer/libs/gst/helpers/gst-plugin-scanner" % options.builddir)
    env["GST_PTP_HELPER"] = os.path.normpath(
        "%s/subprojects/gstreamer/libs/gst/helpers/gst-ptp-helper" % options.builddir)

    if os.name == 'nt':
        lib_path_envvar = 'PATH'
    elif platform.system() == 'Darwin':
        # DYLD_LIBRARY_PATH is stripped when new shells are spawned and can
        # cause issues with runtime linker resolution, so only set it when
        # using --only-environment
        lib_path_envvar = None
        if options.only_environment:
            lib_path_envvar = 'DYLD_LIBRARY_PATH'
    else:
        lib_path_envvar = 'LD_LIBRARY_PATH'

    prepend_env_var(env, "GST_PLUGIN_PATH", os.path.join(SCRIPTDIR, 'subprojects',
                                                        'gst-python', 'plugin'),
                    options.sysroot)
    prepend_env_var(env, "GST_PLUGIN_PATH", os.path.join(PREFIX_DIR, 'lib',
                                                        'gstreamer-1.0'),
                    options.sysroot)
    prepend_env_var(env, "GST_PLUGIN_PATH", os.path.join(options.builddir, 'subprojects',
                                                         'libnice', 'gst'),
                    options.sysroot)
    prepend_env_var(env, "GST_VALIDATE_SCENARIOS_PATH",
                    os.path.join(PREFIX_DIR, 'share', 'gstreamer-1.0',
                                 'validate', 'scenarios'),
                    options.sysroot)
    prepend_env_var(env, "GI_TYPELIB_PATH", os.path.join(PREFIX_DIR, 'lib',
                                                         'lib', 'girepository-1.0'),
                    options.sysroot)
    prepend_env_var(env, "PKG_CONFIG_PATH", os.path.join(PREFIX_DIR, 'lib', 'pkgconfig'),
                    options.sysroot)

    # gst-indent
    prepend_env_var(env, "PATH", os.path.join(SCRIPTDIR, 'scripts'),
                    options.sysroot)

    # tools: gst-launch-1.0, gst-inspect-1.0
    prepend_env_var(env, "PATH", os.path.join(options.builddir, 'subprojects',
                                              'gstreamer', 'tools'),
                    options.sysroot)
    # plugin scanner and generator
    prepend_env_var(env, "PATH", os.path.join(options.builddir, 'subprojects',
                                              'gstreamer', 'docs'),
                    options.sysroot)
    prepend_env_var(env, "PATH", os.path.join(options.builddir, 'subprojects',
                                              'gst-plugins-base', 'tools'),
                    options.sysroot)

    # Library and binary search paths
    prepend_env_var(env, "PATH", os.path.join(PREFIX_DIR, 'bin'),
                    options.sysroot)
    if lib_path_envvar != 'PATH':
        prepend_env_var(env, lib_path_envvar, os.path.join(PREFIX_DIR, 'lib'),
                        options.sysroot)
        prepend_env_var(env, lib_path_envvar, os.path.join(PREFIX_DIR, 'lib64'),
                        options.sysroot)
    elif 'QMAKE' in os.environ:
        # There's no RPATH on Windows, so we need to set PATH for the qt5 DLLs
        prepend_env_var(env, 'PATH', os.path.dirname(os.environ['QMAKE']),
                        options.sysroot)

    meson = get_meson()
    targets_s = subprocess.check_output(meson + ['introspect', options.builddir, '--targets'])
    targets = json.loads(targets_s.decode())
    paths = set()
    mono_paths = set()
    srcdir_path = pathlib.Path(options.srcdir)

    build_options_s = subprocess.check_output(meson + ['introspect', options.builddir, '--buildoptions'])
    build_options = json.loads(build_options_s.decode())
    libdir, = [o['value'] for o in build_options if o['name'] == 'libdir']
    libdir = PurePath(libdir)
    prefix, = [o['value'] for o in build_options if o['name'] == 'prefix']
    bindir, = [o['value'] for o in build_options if o['name'] == 'bindir']
    prefix = PurePath(prefix)
    bindir = prefix / bindir

    global GSTPLUGIN_FILEPATH_REG_TEMPLATE
    GSTPLUGIN_FILEPATH_REG_TEMPLATE = GSTPLUGIN_FILEPATH_REG_TEMPLATE.format(libdir=libdir.as_posix())

    for target in targets:
        filenames = listify(target['filename'])
        if not target['installed']:
            continue
        for filename in filenames:
            root = os.path.dirname(filename)
            if srcdir_path / "subprojects/gst-devtools/validate/plugins" in (srcdir_path / root).parents:
                continue
            if filename.endswith('.dll'):
                mono_paths.add(os.path.join(options.builddir, root))
            if TYPELIB_REG.search(filename):
                prepend_env_var(env, "GI_TYPELIB_PATH",
                                os.path.join(options.builddir, root),
                                options.sysroot)
            elif is_library_target_and_not_plugin(target, filename):
                prepend_env_var(env, lib_path_envvar,
                                os.path.join(options.builddir, root),
                                options.sysroot)
            elif is_binary_target_and_in_path(target, filename, bindir):
                paths.add(os.path.join(options.builddir, root))
            elif is_gio_module(target, filename, options.builddir):
                prepend_env_var(env, 'GIO_EXTRA_MODULES',
                                os.path.join(options.builddir, root),
                                options.sysroot)

    # Search for the Plugin paths file either in the build directory root
    # or check if gstreamer is a subproject of another project
    for sub_directories in [[], ['subprojects', 'gstreamer']]:
        plugin_paths = os.path.join(options.builddir, *sub_directories, 'GstPluginsPath.json')
        if os.path.exists(plugin_paths):
            with open(plugin_paths) as f:
                for plugin_path in json.load(f):
                    prepend_env_var(env, 'GST_PLUGIN_PATH', plugin_path,
                                    options.sysroot)
            break

    # Sort to iterate in a consistent order (`set`s and `hash`es are randomized)
    for p in sorted(paths):
        prepend_env_var(env, 'PATH', p, options.sysroot)

    if os.name != 'nt':
        for p in sorted(mono_paths):
            prepend_env_var(env, "MONO_PATH", p, options.sysroot)

    presets = set()
    encoding_targets = set()
    python_dirs = setup_gdb(options)
    overrides_dirs = set()
    if '--installed' in subprocess.check_output(meson + ['introspect', '-h']).decode():
        installed_s = subprocess.check_output(meson + ['introspect', options.builddir, '--installed'])
        for path, installpath in json.loads(installed_s.decode()).items():
            installpath_parts = pathlib.Path(installpath).parts

            # We want to add all python modules to the PYTHONPATH
            # in a manner consistent with the way they would be imported:
            # For example if the source path /home/meh/foo/bar.py
            # is to be installed in /usr/lib/python/site-packages/foo/bar.py,
            # we want to add /home/meh to the PYTHONPATH.
            # This will only work for projects where the paths to be installed
            # mirror the installed directory layout, for example if the path
            # is /home/meh/baz/bar.py and the install path is
            # /usr/lib/site-packages/foo/bar.py , we will not add anything
            # to PYTHONPATH, but the current approach works with pygobject
            # and gst-python at least.
            py_package = None
            if 'site-packages' in installpath_parts:
                py_package = 'site-packages'
            elif 'dist-packages' in installpath_parts:
                py_package = 'dist-packages'
            if  py_package:
                install_subpath = os.path.join(*installpath_parts[installpath_parts.index(py_package) + 1:])
                if path.endswith(install_subpath):
                    if os.path.commonprefix(["gi/overrides", install_subpath]):
                        overrides_dirs.add(os.path.dirname(path))
                    else:
                        python_dirs.add(path[:len(install_subpath) * -1])

            if path.endswith('.prs'):
                presets.add(os.path.dirname(path))
            elif path.endswith('.gep'):
                encoding_targets.add(
                    os.path.abspath(os.path.join(os.path.dirname(path), '..')))

            if path.endswith('gstomx.conf'):
                prepend_env_var(env, 'GST_OMX_CONFIG_DIR', os.path.dirname(path),
                                options.sysroot)

        for p in sorted(presets):
            prepend_env_var(env, 'GST_PRESET_PATH', p, options.sysroot)

        for t in sorted(encoding_targets):
            prepend_env_var(env, 'GST_ENCODING_TARGET_PATH', t, options.sysroot)

    # Check if meson has generated -uninstalled pkgconfig files
    meson_uninstalled = pathlib.Path(options.builddir) / 'meson-uninstalled'
    if meson_uninstalled.is_dir():
        prepend_env_var(env, 'PKG_CONFIG_PATH', str(meson_uninstalled), options.sysroot)

    for python_dir in sorted(python_dirs):
        prepend_env_var(env, 'PYTHONPATH', python_dir, options.sysroot)

    for python_dir in sorted(overrides_dirs):
        prepend_env_var(env, '_GI_OVERRIDES_PATH', python_dir, options.sysroot)

    mesonpath = os.path.join(SCRIPTDIR, "meson")
    if os.path.join(mesonpath):
        # Add meson/ into PYTHONPATH if we are using a local meson
        prepend_env_var(env, 'PYTHONPATH', mesonpath, options.sysroot)

    # Ensure that gst-python/gi is used first
    prepend_env_var(env, "PYTHONPATH", os.path.join(SCRIPTDIR, 'subprojects', 'gst-python'),
                    options.sysroot)

    # For devhelp books
    if 'XDG_DATA_DIRS' not in env or not env['XDG_DATA_DIRS']:
        # Preserve default paths when empty
        prepend_env_var(env, 'XDG_DATA_DIRS', '/usr/local/share/:/usr/share/', '')

    prepend_env_var(env, 'XDG_DATA_DIRS', os.path.join(options.builddir,
                                                       'subprojects',
                                                       'gst-docs',
                                                       'GStreamer-doc'),
                    options.sysroot)

    if 'XDG_CONFIG_DIRS' not in env or not env['XDG_CONFIG_DIRS']:
        # Preserve default paths when empty
        prepend_env_var(env, 'XDG_CONFIG_DIRS', '/etc/local/xdg:/etc/xdg', '')

    prepend_env_var(env, "XDG_CONFIG_DIRS", os.path.join(PREFIX_DIR, 'etc', 'xdg'),
                    options.sysroot)

    return env


def get_windows_shell():
    command = ['powershell.exe', '-noprofile', '-executionpolicy', 'bypass', '-file',
        os.path.join(SCRIPTDIR, 'data', 'misc', 'cmd_or_ps.ps1')]
    result = subprocess.check_output(command)
    return result.decode().strip()


if __name__ == "__main__":
    parser = argparse.ArgumentParser(prog="gst-env")

    parser.add_argument("--builddir",
                        default=DEFAULT_BUILDDIR,
                        help="The meson build directory")
    parser.add_argument("--srcdir",
                        default=SCRIPTDIR,
                        help="The top level source directory")
    parser.add_argument("--sysroot",
                        default='',
                        help="The sysroot path used during cross-compilation")
    parser.add_argument("--wine",
                        default='',
                        help="Build a wine env based on specified wine command")
    parser.add_argument("--winepath",
                        default='',
                        help="Extra path to set to WINEPATH.")
    parser.add_argument("--only-environment",
                        action='store_true',
                        default=False,
                        help="Do not start a shell, only print required environment.")
    options, args = parser.parse_known_args()

    if not os.path.exists(options.builddir):
        print("GStreamer not built in %s\n\nBuild it and try again" %
              options.builddir)
        exit(1)
    options.builddir = os.path.abspath(options.builddir)

    if not os.path.exists(options.srcdir):
        print("The specified source dir does not exist" %
              options.srcdir)
        exit(1)

    # The following incantation will retrieve the current branch name.
    try:
        gst_version = git("rev-parse", "--symbolic-full-name", "--abbrev-ref", "HEAD",
                          repository_path=options.srcdir).strip('\n')
    except subprocess.CalledProcessError:
        gst_version = "unknown"

    if options.wine:
        gst_version += '-' + os.path.basename(options.wine)

    env = get_subprocess_env(options, gst_version)
    if os.name == 'nt':
        shell = get_windows_shell()
        if shell in ['powershell.exe', 'pwsh.exe']:
            new_args = [shell, '-NoLogo']
            if not args:
                prompt = 'function global:prompt {  "[' + gst_version + '"+"] PS " + $PWD + "> "}'
                new_args += ['-NoExit', '-Command', prompt]
            else:
                new_args += ['-NonInteractive', '-Command'] + args
            args = new_args
        else:
            new_args = [os.environ.get("COMSPEC", r"C:\WINDOWS\system32\cmd.exe")]
            if not args:
                new_args += ['/k', 'prompt [{}] $P$G'.format(gst_version)]
            else:
                new_args += ['/c', 'start', '/b', '/wait'] + args
            args = new_args
    if not args:
        if os.name != 'nt':
            args = [os.environ.get("SHELL", os.path.realpath("/bin/sh"))]
        prompt_export = f'export PS1="[{gst_version}] $PS1"'
        if args[0].endswith('bash') and not str_to_bool(os.environ.get("GST_BUILD_DISABLE_PS1_OVERRIDE", r"FALSE")):
            # Let the GC remove the tmp file
            tmprc = tempfile.NamedTemporaryFile(mode='w')
            bashrc = os.path.expanduser('~/.bashrc')
            if os.path.exists(bashrc):
                with open(bashrc, 'r') as src:
                    shutil.copyfileobj(src, tmprc)
            tmprc.write('\n' + prompt_export)
            tmprc.flush()
            if is_bash_completion_available(options):
                bash_completions_files = []
                for p in BASH_COMPLETION_PATHS:
                    if os.path.exists(p):
                        bash_completions_files += os.listdir(path=p)
                bc_rc = BC_RC.format(bash_completions=' '.join(bash_completions_files), bash_completions_paths=' '.join(BASH_COMPLETION_PATHS))
                tmprc.write(bc_rc)
                tmprc.flush()
            args.append("--rcfile")
            args.append(tmprc.name)
        elif args[0].endswith('fish'):
            prompt_export = None  # FIXME
            # Ignore SIGINT while using fish as the shell to make it behave
            # like other shells such as bash and zsh.
            # See: https://gitlab.freedesktop.org/gstreamer/gst-build/issues/18
            signal.signal(signal.SIGINT, lambda x, y: True)
            # Set the prompt
            args.append('--init-command')
            prompt_cmd = '''functions --copy fish_prompt original_fish_prompt
            function fish_prompt
                echo -n '[{}] '(original_fish_prompt)
            end'''.format(gst_version)
            args.append(prompt_cmd)
        elif args[0].endswith('zsh'):
            prompt_export = f'export PROMPT="[{gst_version}] $PROMPT"'
            tmpdir = tempfile.TemporaryDirectory()
            # Let the GC remove the tmp file
            tmprc = open(os.path.join(tmpdir.name, '.zshrc'), 'w')
            zshrc = os.path.expanduser('~/.zshrc')
            if os.path.exists(zshrc):
                with open(zshrc, 'r') as src:
                    shutil.copyfileobj(src, tmprc)
            tmprc.write('\n' + prompt_export)
            tmprc.flush()
            env['ZDOTDIR'] = tmpdir.name
    try:
        if options.only_environment:
            for name, value in env.items():
                print('{}={}'.format(name, shlex.quote(value)))
                print('export {}'.format(name))
            if prompt_export:
                print(prompt_export)
        else:
            if os.environ.get("CI_PROJECT_NAME"):
                print("Ignoring SIGINT when running on the CI,"
                      " as we get spurious sigint in there for some reason.")
                signal.signal(signal.SIGINT, signal.SIG_IGN)
            exit(subprocess.call(args, close_fds=False, env=env))

    except subprocess.CalledProcessError as e:
        exit(e.returncode)