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Diffstat (limited to 'portage_with_autodep/pym/portage/process.py')
| -rw-r--r-- | portage_with_autodep/pym/portage/process.py | 427 |
1 files changed, 427 insertions, 0 deletions
diff --git a/portage_with_autodep/pym/portage/process.py b/portage_with_autodep/pym/portage/process.py new file mode 100644 index 0000000..6866a2f --- /dev/null +++ b/portage_with_autodep/pym/portage/process.py @@ -0,0 +1,427 @@ +# portage.py -- core Portage functionality +# Copyright 1998-2010 Gentoo Foundation +# Distributed under the terms of the GNU General Public License v2 + + +import atexit +import signal +import sys +import traceback + +from portage import os +from portage import _encodings +from portage import _unicode_encode +import portage +portage.proxy.lazyimport.lazyimport(globals(), + 'portage.util:dump_traceback', +) + +from portage.const import BASH_BINARY, SANDBOX_BINARY, FAKEROOT_BINARY, AUTODEP_LIBRARY +from portage.exception import CommandNotFound + +try: + import resource + max_fd_limit = resource.getrlimit(resource.RLIMIT_NOFILE)[0] +except ImportError: + max_fd_limit = 256 + +if sys.hexversion >= 0x3000000: + basestring = str + +if os.path.isdir("/proc/%i/fd" % os.getpid()): + def get_open_fds(): + return (int(fd) for fd in os.listdir("/proc/%i/fd" % os.getpid()) \ + if fd.isdigit()) +else: + def get_open_fds(): + return range(max_fd_limit) + +sandbox_capable = (os.path.isfile(SANDBOX_BINARY) and + os.access(SANDBOX_BINARY, os.X_OK)) + +autodep_capable = (os.path.isfile(AUTODEP_LIBRARY) and + os.access(AUTODEP_LIBRARY, os.X_OK)) + +fakeroot_capable = (os.path.isfile(FAKEROOT_BINARY) and + os.access(FAKEROOT_BINARY, os.X_OK)) + +def spawn_bash(mycommand, debug=False, opt_name=None, **keywords): + """ + Spawns a bash shell running a specific commands + + @param mycommand: The command for bash to run + @type mycommand: String + @param debug: Turn bash debugging on (set -x) + @type debug: Boolean + @param opt_name: Name of the spawned process (detaults to binary name) + @type opt_name: String + @param keywords: Extra Dictionary arguments to pass to spawn + @type keywords: Dictionary + """ + + args = [BASH_BINARY] + if not opt_name: + opt_name = os.path.basename(mycommand.split()[0]) + if debug: + # Print commands and their arguments as they are executed. + args.append("-x") + args.append("-c") + args.append(mycommand) + return spawn(args, opt_name=opt_name, **keywords) + +def spawn_autodep(mycommand, opt_name=None, **keywords): + if not autodep_capable: + return spawn_bash(mycommand, opt_name=opt_name, **keywords) + if "env" not in keywords or "LOG_SOCKET" not in keywords["env"]: + return spawn_bash(mycommand, opt_name=opt_name, **keywords) + + # Core part: tell the loader to preload logging library + keywords["env"]["LD_PRELOAD"]=AUTODEP_LIBRARY + return spawn_bash(mycommand, opt_name=opt_name, **keywords) + +def spawn_sandbox(mycommand, opt_name=None, **keywords): + if not sandbox_capable: + return spawn_bash(mycommand, opt_name=opt_name, **keywords) + args=[SANDBOX_BINARY] + if not opt_name: + opt_name = os.path.basename(mycommand.split()[0]) + args.append(mycommand) + return spawn(args, opt_name=opt_name, **keywords) + +def spawn_fakeroot(mycommand, fakeroot_state=None, opt_name=None, **keywords): + args=[FAKEROOT_BINARY] + if not opt_name: + opt_name = os.path.basename(mycommand.split()[0]) + if fakeroot_state: + open(fakeroot_state, "a").close() + args.append("-s") + args.append(fakeroot_state) + args.append("-i") + args.append(fakeroot_state) + args.append("--") + args.append(BASH_BINARY) + args.append("-c") + args.append(mycommand) + return spawn(args, opt_name=opt_name, **keywords) + +_exithandlers = [] +def atexit_register(func, *args, **kargs): + """Wrapper around atexit.register that is needed in order to track + what is registered. For example, when portage restarts itself via + os.execv, the atexit module does not work so we have to do it + manually by calling the run_exitfuncs() function in this module.""" + _exithandlers.append((func, args, kargs)) + +def run_exitfuncs(): + """This should behave identically to the routine performed by + the atexit module at exit time. It's only necessary to call this + function when atexit will not work (because of os.execv, for + example).""" + + # This function is a copy of the private atexit._run_exitfuncs() + # from the python 2.4.2 sources. The only difference from the + # original function is in the output to stderr. + exc_info = None + while _exithandlers: + func, targs, kargs = _exithandlers.pop() + try: + func(*targs, **kargs) + except SystemExit: + exc_info = sys.exc_info() + except: # No idea what they called, so we need this broad except here. + dump_traceback("Error in portage.process.run_exitfuncs", noiselevel=0) + exc_info = sys.exc_info() + + if exc_info is not None: + if sys.hexversion >= 0x3000000: + raise exc_info[0](exc_info[1]).with_traceback(exc_info[2]) + else: + exec("raise exc_info[0], exc_info[1], exc_info[2]") + +atexit.register(run_exitfuncs) + +# We need to make sure that any processes spawned are killed off when +# we exit. spawn() takes care of adding and removing pids to this list +# as it creates and cleans up processes. +spawned_pids = [] +def cleanup(): + while spawned_pids: + pid = spawned_pids.pop() + try: + # With waitpid and WNOHANG, only check the + # first element of the tuple since the second + # element may vary (bug #337465). + if os.waitpid(pid, os.WNOHANG)[0] == 0: + os.kill(pid, signal.SIGTERM) + os.waitpid(pid, 0) + except OSError: + # This pid has been cleaned up outside + # of spawn(). + pass + +atexit_register(cleanup) + +def spawn(mycommand, env={}, opt_name=None, fd_pipes=None, returnpid=False, + uid=None, gid=None, groups=None, umask=None, logfile=None, + path_lookup=True, pre_exec=None): + """ + Spawns a given command. + + @param mycommand: the command to execute + @type mycommand: String or List (Popen style list) + @param env: A dict of Key=Value pairs for env variables + @type env: Dictionary + @param opt_name: an optional name for the spawn'd process (defaults to the binary name) + @type opt_name: String + @param fd_pipes: A dict of mapping for pipes, { '0': stdin, '1': stdout } for example + @type fd_pipes: Dictionary + @param returnpid: Return the Process IDs for a successful spawn. + NOTE: This requires the caller clean up all the PIDs, otherwise spawn will clean them. + @type returnpid: Boolean + @param uid: User ID to spawn as; useful for dropping privilages + @type uid: Integer + @param gid: Group ID to spawn as; useful for dropping privilages + @type gid: Integer + @param groups: Group ID's to spawn in: useful for having the process run in multiple group contexts. + @type groups: List + @param umask: An integer representing the umask for the process (see man chmod for umask details) + @type umask: Integer + @param logfile: name of a file to use for logging purposes + @type logfile: String + @param path_lookup: If the binary is not fully specified then look for it in PATH + @type path_lookup: Boolean + @param pre_exec: A function to be called with no arguments just prior to the exec call. + @type pre_exec: callable + + logfile requires stdout and stderr to be assigned to this process (ie not pointed + somewhere else.) + + """ + + # mycommand is either a str or a list + if isinstance(mycommand, basestring): + mycommand = mycommand.split() + + if sys.hexversion < 0x3000000: + # Avoid a potential UnicodeEncodeError from os.execve(). + env_bytes = {} + for k, v in env.items(): + env_bytes[_unicode_encode(k, encoding=_encodings['content'])] = \ + _unicode_encode(v, encoding=_encodings['content']) + env = env_bytes + del env_bytes + + # If an absolute path to an executable file isn't given + # search for it unless we've been told not to. + binary = mycommand[0] + if binary not in (BASH_BINARY, SANDBOX_BINARY, FAKEROOT_BINARY) and \ + (not os.path.isabs(binary) or not os.path.isfile(binary) + or not os.access(binary, os.X_OK)): + binary = path_lookup and find_binary(binary) or None + if not binary: + raise CommandNotFound(mycommand[0]) + + # If we haven't been told what file descriptors to use + # default to propagating our stdin, stdout and stderr. + if fd_pipes is None: + fd_pipes = { + 0:sys.stdin.fileno(), + 1:sys.stdout.fileno(), + 2:sys.stderr.fileno(), + } + + # mypids will hold the pids of all processes created. + mypids = [] + + if logfile: + # Using a log file requires that stdout and stderr + # are assigned to the process we're running. + if 1 not in fd_pipes or 2 not in fd_pipes: + raise ValueError(fd_pipes) + + # Create a pipe + (pr, pw) = os.pipe() + + # Create a tee process, giving it our stdout and stderr + # as well as the read end of the pipe. + mypids.extend(spawn(('tee', '-i', '-a', logfile), + returnpid=True, fd_pipes={0:pr, + 1:fd_pipes[1], 2:fd_pipes[2]})) + + # We don't need the read end of the pipe, so close it. + os.close(pr) + + # Assign the write end of the pipe to our stdout and stderr. + fd_pipes[1] = pw + fd_pipes[2] = pw + + pid = os.fork() + + if not pid: + try: + _exec(binary, mycommand, opt_name, fd_pipes, + env, gid, groups, uid, umask, pre_exec) + except SystemExit: + raise + except Exception as e: + # We need to catch _any_ exception so that it doesn't + # propagate out of this function and cause exiting + # with anything other than os._exit() + sys.stderr.write("%s:\n %s\n" % (e, " ".join(mycommand))) + traceback.print_exc() + sys.stderr.flush() + os._exit(1) + + # Add the pid to our local and the global pid lists. + mypids.append(pid) + spawned_pids.append(pid) + + # If we started a tee process the write side of the pipe is no + # longer needed, so close it. + if logfile: + os.close(pw) + + # If the caller wants to handle cleaning up the processes, we tell + # it about all processes that were created. + if returnpid: + return mypids + + # Otherwise we clean them up. + while mypids: + + # Pull the last reader in the pipe chain. If all processes + # in the pipe are well behaved, it will die when the process + # it is reading from dies. + pid = mypids.pop(0) + + # and wait for it. + retval = os.waitpid(pid, 0)[1] + + # When it's done, we can remove it from the + # global pid list as well. + spawned_pids.remove(pid) + + if retval: + # If it failed, kill off anything else that + # isn't dead yet. + for pid in mypids: + # With waitpid and WNOHANG, only check the + # first element of the tuple since the second + # element may vary (bug #337465). + if os.waitpid(pid, os.WNOHANG)[0] == 0: + os.kill(pid, signal.SIGTERM) + os.waitpid(pid, 0) + spawned_pids.remove(pid) + + # If it got a signal, return the signal that was sent. + if (retval & 0xff): + return ((retval & 0xff) << 8) + + # Otherwise, return its exit code. + return (retval >> 8) + + # Everything succeeded + return 0 + +def _exec(binary, mycommand, opt_name, fd_pipes, env, gid, groups, uid, umask, + pre_exec): + + """ + Execute a given binary with options + + @param binary: Name of program to execute + @type binary: String + @param mycommand: Options for program + @type mycommand: String + @param opt_name: Name of process (defaults to binary) + @type opt_name: String + @param fd_pipes: Mapping pipes to destination; { 0:0, 1:1, 2:2 } + @type fd_pipes: Dictionary + @param env: Key,Value mapping for Environmental Variables + @type env: Dictionary + @param gid: Group ID to run the process under + @type gid: Integer + @param groups: Groups the Process should be in. + @type groups: Integer + @param uid: User ID to run the process under + @type uid: Integer + @param umask: an int representing a unix umask (see man chmod for umask details) + @type umask: Integer + @param pre_exec: A function to be called with no arguments just prior to the exec call. + @type pre_exec: callable + @rtype: None + @returns: Never returns (calls os.execve) + """ + + # If the process we're creating hasn't been given a name + # assign it the name of the executable. + if not opt_name: + opt_name = os.path.basename(binary) + + # Set up the command's argument list. + myargs = [opt_name] + myargs.extend(mycommand[1:]) + + # Use default signal handlers in order to avoid problems + # killing subprocesses as reported in bug #353239. + signal.signal(signal.SIGINT, signal.SIG_DFL) + signal.signal(signal.SIGTERM, signal.SIG_DFL) + + # Quiet killing of subprocesses by SIGPIPE (see bug #309001). + signal.signal(signal.SIGPIPE, signal.SIG_DFL) + + # Avoid issues triggered by inheritance of SIGQUIT handler from + # the parent process (see bug #289486). + signal.signal(signal.SIGQUIT, signal.SIG_DFL) + + _setup_pipes(fd_pipes) + + # Set requested process permissions. + if gid: + os.setgid(gid) + if groups: + os.setgroups(groups) + if uid: + os.setuid(uid) + if umask: + os.umask(umask) + if pre_exec: + pre_exec() + + # And switch to the new process. + os.execve(binary, myargs, env) + +def _setup_pipes(fd_pipes): + """Setup pipes for a forked process.""" + my_fds = {} + # To protect from cases where direct assignment could + # clobber needed fds ({1:2, 2:1}) we first dupe the fds + # into unused fds. + for fd in fd_pipes: + my_fds[fd] = os.dup(fd_pipes[fd]) + # Then assign them to what they should be. + for fd in my_fds: + os.dup2(my_fds[fd], fd) + # Then close _all_ fds that haven't been explicitly + # requested to be kept open. + for fd in get_open_fds(): + if fd not in my_fds: + try: + os.close(fd) + except OSError: + pass + +def find_binary(binary): + """ + Given a binary name, find the binary in PATH + + @param binary: Name of the binary to find + @type string + @rtype: None or string + @returns: full path to binary or None if the binary could not be located. + """ + for path in os.environ.get("PATH", "").split(":"): + filename = "%s/%s" % (path, binary) + if os.access(filename, os.X_OK) and os.path.isfile(filename): + return filename + return None |