#!/usr/bin/env python3
# libvirt 'run' programs locally script
# Copyright (C) 2012-2021 Red Hat, Inc.
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; If not, see
# <http://www.gnu.org/licenses/>.

#----------------------------------------------------------------------
#
# With this script you can run libvirt programs without needing to
# install them first.  You just have to do for example:
#
#   ./run virsh [args ...]
#
# Note that this runs the locally compiled copy of virsh which
# is usually want you want.
#
# You can also run the C programs under valgrind like this:
#
#   ./run valgrind [valgrind opts...] ./program
#
# or under gdb:
#
#   ./run gdb --args ./program
#
# This also works with sudo (eg. if you need root access for libvirt):
#
#   sudo ./run virsh list --all
#
#----------------------------------------------------------------------

import os
import os.path
import random
import sys

# Function to intelligently prepend a path to an environment variable.
# See https://stackoverflow.com/a/9631350
def prepend(env, varname, extradir):
    if varname in os.environ:
        env[varname] = extradir + ":" + env[varname]
    else:
        env[varname] = extradir

here = "@abs_builddir@"

if len(sys.argv) < 2:
    print("syntax: %s BINARY [ARGS...]" % sys.argv[0], file=sys.stderr)
    sys.exit(1)

prog = sys.argv[1]
args = sys.argv[1:]
env = os.environ


prepend(env, "LD_LIBRARY_PATH", os.path.join(here, "src"))
prepend(env, "PKG_CONFIG_PATH", os.path.join(here, "src"))
prepend(env, "PATH", os.path.join(here, "tools"))

# Ensure that any 3rd party apps using libvirt.so from the build tree get
# files resolved to the build/source tree too. Typically useful for language
# bindings running tests against non-installed libvirt.
env["LIBVIRT_DIR_OVERRIDE"] = "1"

# This is a cheap way to find some use-after-free and uninitialized
# read problems when using glibc.
env["MALLOC_PERTURB_"] = "%d" % random.randint(1, 255)

# Run the program.
os.execvpe(prog, args, env)