TechEmpower.FrameworkBenchmarks/toolset/setup/linux/setup_util.py

import re
import os
import subprocess
import platform

# Replaces all text found using the regular expression to_replace with the supplied replacement.
def replace_text(file, to_replace, replacement):
    with open(file, "r") as conf:
        contents = conf.read()
    replaced_text = re.sub(to_replace, replacement, contents)
    with open(file, "w") as f:
        f.write(replaced_text)

# Replaces the current process environment with the one found in 
# config file. Retains a few original vars (HOME,PATH, etc) by default. 
# Optionally allows specification of a command to be run before loading
# the environment, to allow the framework to set environment variables
# Note: This command *cannot* print to stdout!
#
# Note: This will not replace the sudo environment (e.g. subprocess.check_call("sudo <command>")). 
# If you must use sudo, consider sudo sh -c ". <config> && your_command"
def replace_environ(config=None, root=None, print_result=False, command='true'):

    if platform.system().lower() == 'windows':

        pass

    else:
    
        # Clean up our current environment, preserving some important items
        mini_environ = {}
        for envname in ['HOME', 'PATH', 'USER', 'LD_LIBRARY_PATH', 'PYTHONPATH', 'FWROOT']:
          if envname in os.environ:
            mini_environ[envname] = os.environ[envname]
        for key in os.environ:
          if key.startswith('TFB_'):    # Any TFB_ variables are preserved
            mini_environ[key] = os.environ[key]
        os.environ.clear()

        # Use FWROOT if explicitely provided
        if root is not None: 
          mini_environ['FWROOT']=root
        

        # Run command, source config file, and store resulting environment
        setup_env = "%s && . %s && env" % (command, config)
        env = subprocess.check_output(setup_env, shell=True, env=mini_environ,
          executable='/bin/bash')
        for line in env.split('\n'):
            try:
                key, value = line.split('=', 1)
                # If we already have this TFB_ variable, do not overwrite
                if key.startswith('TFB_') and key in mini_environ:
                    os.environ[key]=mini_environ[key]
                else:
                    os.environ[key]=value    
            except:
                if not line: # Don't warn for empty line
                    continue 
                print "WARN: Line '%s' from '%s' is not an environment variable" % (line, config)
                continue
        if print_result:
            out = subprocess.check_output('env', shell=True, executable='/bin/bash')
            print "Environment after loading %s" %config
            print out

# Queries the shell for the value of FWROOT
def get_fwroot():

    if platform.system().lower() == 'windows':

        fwroot = "C:\FrameworkBenchmarks"
        return fwroot

    else:
    
        try:
            # Use printf to avoid getting a newline
            # Redirect to avoid stderr printing
            fwroot = subprocess.check_output('printf $FWROOT 2> /dev/null', shell=True, executable='/bin/bash')
            return fwroot
        except subprocess.CalledProcessError:
            return "";

# Turns absolute path into path relative to FWROOT
# Assumes path is underneath FWROOT, not above
# 
# Useful for clean presentation of paths 
# e.g. /foo/bar/benchmarks/go/bash_profile.sh
# v.s. FWROOT/go/bash_profile.sh 
def path_relative_to_root(path):
    # Requires bash shell parameter expansion
    return subprocess.check_output("D=%s && printf \"${D#%s}\""%(path, get_fwroot()), shell=True, executable='/bin/bash')