Re: [libvirt PATCH 1/2] build: convert the run script to use Python

On Thu, Mar 18, 2021 at 06:29:17PM +0000, Daniel P. Berrangé wrote: > This fits with the goal of eliminating non-Python scripting languages, > and makes forthcoming changes far easier. > > Signed-off-by: Daniel P. Berrangé <berrange(a)redhat.com&gt; > --- > run.in | 45 ++++++++++++++++++++++++++------------------- > 1 file changed, 26 insertions(+), 19 deletions(-) > > diff --git a/run.in b/run.in > index 6ddf5fc58f..99c67c586a 100644 > --- a/run.in > +++ b/run.in > @@ -1,6 +1,6 @@ > -#!/bin/sh > +#!/usr/bin/env python3 > # libvirt 'run' programs locally script > -# Copyright (C) 2012-2013 Red Hat, Inc. > +# 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 > @@ -40,35 +40,42 @@ > # > #---------------------------------------------------------------------- > > +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 > -prepend() > -{ > - eval $1="$2\${$1:+:\$$1}" > -} > +def prepend(env, varname, extradir): > + if varname in os.environ: > + env[varname] = extradir + ":" + env[varname] > + else: > + env[varname] = extradir > + > +here = "@abs_builddir@" > > -# Find this script. > -b=@abs_builddir@ > +if len(sys.argv) < 2: > + print("syntax: %s BINARY [ARGS...]" % sys.argv[0], file=sys.stderr) > + sys.exit(1) > > -prepend LD_LIBRARY_PATH "$b/src" > -export LD_LIBRARY_PATH > +prog = sys.argv[1] > +args = sys.argv[1:] > +env = os.environ > > -prepend PKG_CONFIG_PATH "$b/src" > -export PKG_CONFIG_PATH > > -prepend PATH "$b/tools" > -export PATH > +prepend(env, "LD_LIBRARY_PATH", os.path.join(here, "src")) > +prepend(env, "PKG_CONFIG_PATH", os.path.join(here, "src")) > +prepend(env, "PATH", os.path.join(here, "tools")) > > # Ensure that any 3rd party apps using libvirt.so from the build tree get > # files resolved to the build/source tree too. Typically useful for language > # bindings running tests against non-installed libvirt. > -LIBVIRT_DIR_OVERRIDE=1 > -export LIBVIRT_DIR_OVERRIDE > +env["LIBVIRT_DIR_OVERRIDE"] = "1" > > # This is a cheap way to find some use-after-free and uninitialized > # read problems when using glibc. > -random_val="$(awk 'BEGIN{srand(); print 1+int(255*rand())}' < /dev/null)" > -export MALLOC_PERTURB_=$random_val > +env["MALLOC_PERTURB_"] = "%d" % random.randint(1, 255) > > # Run the program. > -exec "$@" > +os.execve(prog, args, env) This is not functionally equivalent as the shell script modified also its own PATH variable and then the exec could search that. If I am reading the docs correctly, then os.execvpe() can do both of that, so I think you meant to use that here.

If yes, than with that change: Reviewed-by: Martin Kletzander <mkletzan(a)redhat.com&gt;