]> git.donarmstrong.com Git - deb_pkgs/autorandr.git/blobdiff - autorandr.py
Introduce --batch option to autorandr: Run autorandr for each user with an X11 session
[deb_pkgs/autorandr.git] / autorandr.py
index 42a9dac3e96a931f8bf48e77a36f4f575fdf2ddf..548f3129767ab32b52b561dc4f0f2fd6ab4bfd79 100755 (executable)
 #
 
 from __future__ import print_function
-import copy
-import getopt
 
 import binascii
+import copy
+import getopt
 import hashlib
 import os
+import posix
+import pwd
 import re
 import subprocess
 import sys
-from distutils.version import LooseVersion as Version
+import shutil
+import time
 
-from itertools import chain
 from collections import OrderedDict
+from distutils.version import LooseVersion as Version
+from functools import reduce
+from itertools import chain
+
+try:
+    input = raw_input
+except NameError:
+    pass
 
 virtual_profiles = [
     # (name, description, callback)
@@ -50,12 +60,17 @@ Usage: autorandr [options]
 -h, --help              get this small help
 -c, --change            reload current setup
 -s, --save <profile>    save your current setup to profile <profile>
+-r, --remove <profile>  remove profile <profile>
 -l, --load <profile>    load profile <profile>
 -d, --default <profile> make profile <profile> the default profile
+--skip-options <option> comma separated list of xrandr arguments (e.g. "gamma")
+                        to skip both in detecting changes and applying a profile
 --force                 force (re)loading of a profile
 --fingerprint           fingerprint your current hardware setup
 --config                dump your current xrandr setup
 --dry-run               don't change anything, only print the xrandr commands
+--debug                 enable verbose output
+--batch                 run autorandr for all users with active X11 sessions
 
  To prevent a profile from being loaded, place a script call "block" in its
  directory. The script is evaluated before the screen setup is inspected, and
@@ -97,10 +112,11 @@ class AutorandrException(Exception):
         if self.line:
             retval.append(" (line %d)" % self.line)
         if self.original_exception:
-            retval.append(":\n  " % self.line)
+            retval.append(":\n  ")
             retval.append(str(self.original_exception).replace("\n", "\n  "))
         if self.report_bug:
-            retval.append("\nThis appears to be a bug. Please help improving autorandr by reporting it upstream."
+            retval.append("\nThis appears to be a bug. Please help improving autorandr by reporting it upstream:"
+                          "\nhttps://github.com/phillipberndt/autorandr/issues"
                          "\nPlease attach the output of `xrandr --verbose` to your bug report if appropriate.")
         return "".join(retval)
 
@@ -129,7 +145,7 @@ class XrandrOutput(object):
         (?:[\ \t]*tracking\ (?P<tracking>[0-9]+x[0-9]+\+[0-9]+\+[0-9]+))?               # Tracking information
         (?:[\ \t]*border\ (?P<border>(?:[0-9]+/){3}[0-9]+))?                            # Border information
         (?:\s*(?:                                                                       # Properties of the output
-            Gamma: (?P<gamma>[0-9\.: ]+) |                                              # Gamma value
+            Gamma: (?P<gamma>(?:inf|[0-9\.: e])+) |                                     # Gamma value
             Transform: (?P<transform>(?:[\-0-9\. ]+\s+){3}) |                           # Transformation matrix
             EDID: (?P<edid>\s*?(?:\\n\\t\\t[0-9a-f]+)+) |                               # EDID of the output
             (?![0-9])[^:\s][^:\n]+:.*(?:\s\\t[\\t ].+)*                                 # Other properties
@@ -165,7 +181,11 @@ class XrandrOutput(object):
     EDID_UNAVAILABLE = "--CONNECTED-BUT-EDID-UNAVAILABLE-"
 
     def __repr__(self):
-        return "<%s%s %s>" % (self.output, (" %s..%s" % (self.edid[:5], self.edid[-5:])) if self.edid else "", " ".join(self.option_vector))
+        return "<%s%s %s>" % (self.output, self.short_edid, " ".join(self.option_vector))
+
+    @property
+    def short_edid(self):
+        return ("%s..%s" % (self.edid[:5], self.edid[-5:])) if self.edid else ""
 
     @property
     def options_with_defaults(self):
@@ -178,7 +198,12 @@ class XrandrOutput(object):
         if xrandr_version() >= Version("1.2"):
             options.update(self.XRANDR_12_DEFAULTS)
         options.update(self.options)
-        return options
+        return { a: b for a, b in options.items() if a not in self.ignored_options }
+
+    @property
+    def filtered_options(self):
+        "Return a dictionary of options without ignored options"
+        return { a: b for a, b in self.options.items() if a not in self.ignored_options }
 
     @property
     def option_vector(self):
@@ -188,7 +213,7 @@ class XrandrOutput(object):
     @property
     def option_string(self):
         "Return the command line parameters in the configuration file format"
-        return "\n".join([ " ".join(option) if option[1] else option[0] for option in chain((("output", self.output),), sorted(self.options.items()))])
+        return "\n".join([ " ".join(option) if option[1] else option[0] for option in chain((("output", self.output),), sorted(self.filtered_options.items()))])
 
     @property
     def sort_key(self):
@@ -208,8 +233,13 @@ class XrandrOutput(object):
         self.output = output
         self.edid = edid
         self.options = options
+        self.ignored_options = []
         self.remove_default_option_values()
 
+    def set_ignored_options(self, options):
+        "Set a list of xrandr options that are never used (neither when comparing configurations nor when applying them)"
+        self.ignored_options = list(options)
+
     def remove_default_option_values(self):
         "Remove values from the options dictionary that are superflous"
         if "off" in self.options and len(self.options.keys()) > 1:
@@ -291,6 +321,10 @@ class XrandrOutput(object):
                         print("Warning: Output %s has a transformation applied. Could not determine correct mode! Using `%s'." % (match["output"], options["mode"]), file=sys.stderr)
             if match["gamma"]:
                 gamma = match["gamma"].strip()
+                # xrandr prints different values in --verbose than it accepts as a parameter value for --gamma
+                # Also, it is not able to work with non-standard gamma ramps. Finally, it auto-corrects 0 to 1,
+                # so we approximate by 1e-10.
+                gamma = ":".join([ str(max(1e-10, round(1./float(x), 3))) for x in gamma.split(":") ])
                 options["gamma"] = gamma
             if match["rate"]:
                 options["rate"] = match["rate"]
@@ -332,8 +366,32 @@ class XrandrOutput(object):
                 return hashlib.md5(binascii.unhexlify(self.edid)).hexdigest() == other.edid
         return self.edid == other.edid
 
+    def __ne__(self, other):
+        return not (self == other)
+
     def __eq__(self, other):
-        return self.edid_equals(other) and self.output == other.output and self.options == other.options
+        return self.edid_equals(other) and self.output == other.output and self.filtered_options == other.filtered_options
+
+    def verbose_diff(self, other):
+        "Compare to another XrandrOutput and return a list of human readable differences"
+        diffs = []
+        if not self.edid_equals(other):
+            diffs.append("EDID `%s' differs from `%s'" % (self.short_edid, other.short_edid))
+        if self.output != other.output:
+            diffs.append("Output name `%s' differs from `%s'" % (self.output, other.output))
+        if "off" in self.options and "off" not in other.options:
+            diffs.append("The output is disabled currently, but active in the new configuration")
+        elif "off" in other.options and "off" not in self.options:
+            diffs.append("The output is currently enabled, but inactive in the new configuration")
+        else:
+            for name in set(chain.from_iterable((self.options.keys(), other.options.keys()))):
+                if name not in other.options:
+                    diffs.append("Option --%s %sis not present in the new configuration" % (name, "(= `%s') " % self.options[name] if self.options[name] else ""))
+                elif name not in self.options:
+                    diffs.append("Option --%s (`%s' in the new configuration) is not present currently" % (name, other.options[name]))
+                elif self.options[name] != other.options[name]:
+                    diffs.append("Option --%s %sis `%s' in the new configuration" % (name, "(= `%s') " % self.options[name] if self.options[name] else "", other.options[name]))
+        return diffs
 
 def xrandr_version():
     "Return the version of XRandR that this system uses"
@@ -436,12 +494,13 @@ def find_profiles(current_config, profiles):
             detected_profiles.append(profile_name)
     return detected_profiles
 
-def profile_blocked(profile_path):
-    "Check if a profile is blocked"
-    script = os.path.join(profile_path, "block")
-    if not os.access(script, os.X_OK | os.F_OK):
-        return False
-    return subprocess.call(script) == 0
+def profile_blocked(profile_path, meta_information=None):
+    """Check if a profile is blocked.
+
+    meta_information is expected to be an dictionary. It will be passed to the block scripts
+    in the environment, as variables called AUTORANDR_<CAPITALIZED_KEY_HERE>.
+    """
+    return not exec_scripts(profile_path, "block", meta_information)
 
 def output_configuration(configuration, config):
     "Write a configuration file"
@@ -473,6 +532,25 @@ def update_mtime(filename):
     except:
         return False
 
+def call_and_retry(*args, **kwargs):
+    """Wrapper around subprocess.call that retries failed calls.
+
+    This function calls subprocess.call and on non-zero exit states,
+    waits a second and then retries once. This mitigates #47,
+    a timing issue with some drivers.
+    """
+    kwargs_redirected = dict(kwargs)
+    if hasattr(subprocess, "DEVNULL"):
+        kwargs_redirected["stdout"] = getattr(subprocess, "DEVNULL")
+    else:
+        kwargs_redirected["stdout"] = open(os.devnull, "w")
+    kwargs_redirected["stderr"] = kwargs_redirected["stdout"]
+    retval = subprocess.call(*args, **kwargs_redirected)
+    if retval != 0:
+        time.sleep(1)
+        retval = subprocess.call(*args, **kwargs)
+    return retval
+
 def apply_configuration(new_configuration, current_configuration, dry_run=False):
     "Apply a configuration"
     outputs = sorted(new_configuration.keys(), key=lambda x: new_configuration[x].sort_key)
@@ -495,6 +573,8 @@ def apply_configuration(new_configuration, current_configuration, dry_run=False)
     #   the xrandr call fails with an invalid RRSetScreenSize parameter error.
     #   Update the configuration in 3 passes in that case.  (On Haswell graphics,
     #   at least.)
+    # - Some implementations can not handle --transform at all, so avoid it unless
+    #   necessary. (See https://github.com/phillipberndt/autorandr/issues/37)
 
     auxiliary_changes_pre = []
     disable_outputs = []
@@ -506,20 +586,31 @@ def apply_configuration(new_configuration, current_configuration, dry_run=False)
         else:
             if "off" not in current_configuration[output].options:
                 remain_active_count += 1
-            enable_outputs.append(new_configuration[output].option_vector)
-            if xrandr_version() >= Version("1.3.0") and "transform" in current_configuration[output].options:
-                auxiliary_changes_pre.append(["--output", output, "--transform", "none"])
+
+            option_vector = new_configuration[output].option_vector
+            if xrandr_version() >= Version("1.3.0"):
+                if "transform" in current_configuration[output].options:
+                    auxiliary_changes_pre.append(["--output", output, "--transform", "none"])
+                else:
+                    try:
+                        transform_index = option_vector.index("--transform")
+                        if option_vector[transform_index+1] == XrandrOutput.XRANDR_DEFAULTS["transform"]:
+                            option_vector = option_vector[:transform_index] + option_vector[transform_index+2:]
+                    except ValueError:
+                        pass
+
+            enable_outputs.append(option_vector)
 
     # Perform pe-change auxiliary changes
     if auxiliary_changes_pre:
         argv = base_argv + list(chain.from_iterable(auxiliary_changes_pre))
-        if subprocess.call(argv) != 0:
+        if call_and_retry(argv) != 0:
             raise AutorandrException("Command failed: %s" % " ".join(argv))
 
     # Disable unused outputs, but make sure that there always is at least one active screen
     disable_keep = 0 if remain_active_count else 1
     if len(disable_outputs) > disable_keep:
-        if subprocess.call(base_argv + list(chain.from_iterable(disable_outputs[:-1] if disable_keep else disable_outputs))) != 0:
+        if call_and_retry(base_argv + list(chain.from_iterable(disable_outputs[:-1] if disable_keep else disable_outputs))) != 0:
             # Disabling the outputs failed. Retry with the next command:
             # Sometimes disabling of outputs fails due to an invalid RRSetScreenSize.
             # This does not occur if simultaneously the primary screen is reset.
@@ -538,9 +629,16 @@ def apply_configuration(new_configuration, current_configuration, dry_run=False)
     operations = disable_outputs + enable_outputs
     for index in range(0, len(operations), 2):
         argv = base_argv + list(chain.from_iterable(operations[index:index+2]))
-        if subprocess.call(argv) != 0:
+        if call_and_retry(argv) != 0:
             raise AutorandrException("Command failed: %s" % " ".join(argv))
 
+def is_equal_configuration(source_configuration, target_configuration):
+    "Check if all outputs from target are already configured correctly in source"
+    for output in target_configuration.keys():
+        if (output not in source_configuration) or (source_configuration[output] != target_configuration[output]):
+            return False
+    return True
+
 def add_unused_outputs(source_configuration, target_configuration):
     "Add outputs that are missing in target to target, in 'off' state"
     for output_name, output in source_configuration.items():
@@ -557,13 +655,13 @@ def generate_virtual_profile(configuration, modes, profile_name):
     "Generate one of the virtual profiles"
     configuration = copy.deepcopy(configuration)
     if profile_name == "common":
-        common_resolution = [ set(( ( mode["width"], mode["height"] ) for mode in output )) for output in modes.values() ]
+        common_resolution = [ set(( ( mode["width"], mode["height"] ) for mode in output_modes )) for output, output_modes in modes.items() if configuration[output].edid ]
         common_resolution = reduce(lambda a, b: a & b, common_resolution[1:], common_resolution[0])
         common_resolution = sorted(common_resolution, key=lambda a: int(a[0])*int(a[1]))
         if common_resolution:
             for output in configuration:
                 configuration[output].options = {}
-                if output in modes:
+                if output in modes and configuration[output].edid:
                     configuration[output].options["mode"] = [ x["name"] for x in sorted(modes[output], key=lambda x: 0 if x["preferred"] else 1) if x["width"] == common_resolution[-1][0] and x["height"] == common_resolution[-1][1] ][0]
                     configuration[output].options["pos"] = "0x0"
                 else:
@@ -579,7 +677,7 @@ def generate_virtual_profile(configuration, modes, profile_name):
 
         for output in configuration:
             configuration[output].options = {}
-            if output in modes:
+            if output in modes and configuration[output].edid:
                 mode = sorted(modes[output], key=lambda a: int(a["width"])*int(a["height"]) + (10**6 if a["preferred"] else 0))[-1]
                 configuration[output].options["mode"] = mode["name"]
                 configuration[output].options["rate"] = mode["rate"]
@@ -589,6 +687,23 @@ def generate_virtual_profile(configuration, modes, profile_name):
                 configuration[output].options["off"] = None
     return configuration
 
+def print_profile_differences(one, another):
+    "Print the differences between two profiles for debugging"
+    if one == another:
+        return
+    print("| Differences between the two profiles:", file=sys.stderr)
+    for output in set(chain.from_iterable((one.keys(), another.keys()))):
+        if output not in one:
+            if "off" not in another[output].options:
+                print("| Output `%s' is missing from the active configuration" % output, file=sys.stderr)
+        elif output not in another:
+            if "off" not in one[output].options:
+                print("| Output `%s' is missing from the new configuration" % output, file=sys.stderr)
+        else:
+            for line in one[output].verbose_diff(another[output]):
+                print("| [Output %s] %s" % (output, line), file=sys.stderr)
+    print ("\\-", file=sys.stderr)
+
 def exit_help():
     "Print help and exit"
     print(help_text)
@@ -596,23 +711,142 @@ def exit_help():
         print("  %-10s %s" % profile[:2])
     sys.exit(0)
 
-def exec_scripts(profile_path, script_name):
-    "Run userscripts"
-    for script in (os.path.join(profile_path, script_name), os.path.join(os.path.dirname(profile_path), script_name)):
-        if os.access(script, os.X_OK | os.F_OK):
-            subprocess.call(script)
+def exec_scripts(profile_path, script_name, meta_information=None):
+    """"Run userscripts
+
+    This will run all executables from the profile folder, and global per-user
+    and system-wide configuration folders, named script_name or residing in
+    subdirectories named script_name.d.
+
+    meta_information is expected to be an dictionary. It will be passed to the block scripts
+    in the environment, as variables called AUTORANDR_<CAPITALIZED_KEY_HERE>.
+
+    Returns True unless any of the scripts exited with non-zero exit status.
+    """
+    all_ok = True
+    if meta_information:
+        env = os.environ.copy()
+        env.update({ "AUTORANDR_%s" % str(key).upper(): str(value) for (key, value) in meta_information.items() })
+    else:
+        env = os.environ.copy()
+
+    # If there are multiple candidates, the XDG spec tells to only use the first one.
+    ran_scripts = set()
+
+    user_profile_path = os.path.expanduser("~/.autorandr")
+    if not os.path.isdir(user_profile_path):
+        user_profile_path = os.path.join(os.environ.get("XDG_CONFIG_HOME", os.path.expanduser("~/.config")), "autorandr")
+
+    for folder in chain((profile_path, os.path.dirname(profile_path), user_profile_path),
+                        (os.path.join(x, "autorandr") for x in os.environ.get("XDG_CONFIG_DIRS", "/etc/xdg").split(":"))):
+
+        if script_name not in ran_scripts:
+            script = os.path.join(folder, script_name)
+            if os.access(script, os.X_OK | os.F_OK):
+                all_ok &= subprocess.call(script, env=env) != 0
+                ran_scripts.add(script_name)
+
+        script_folder = os.path.join(folder, "%s.d" % script_name)
+        if os.access(script_folder, os.R_OK | os.X_OK) and os.path.isdir(script_folder):
+            for file_name in os.listdir(script_folder):
+                check_name = "d/%s" % (file_name,)
+                if check_name not in ran_scripts:
+                    script = os.path.join(script_folder, file_name)
+                    if os.access(script, os.X_OK | os.F_OK):
+                        all_ok &= subprocess.call(script, env=env) != 0
+                        ran_scripts.add(check_name)
+
+    return all_ok
+
+def dispatch_call_to_sessions(argv):
+    """Invoke autorandr for each open local X11 session with the given options.
+
+    The function iterates over all processes not owned by root and checks
+    whether they have a DISPLAY variable set. It strips the screen from any
+    variable it finds (i.e. :0.0 becomes :0) and checks whether this display
+    has been handled already. If it has not, it forks, changes uid/gid to
+    the user owning the process, reuses the process's environment and runs
+    autorandr with the parameters from argv.
+
+    This function requires root permissions. It only works for X11 servers that
+    have at least one non-root process running. It is susceptible for attacks
+    where one user runs a process with another user's DISPLAY variable - in
+    this case, it might happen that autorandr is invoked for the other user,
+    which won't work. Since no other harm than prevention of automated
+    execution of autorandr can be done this way, the assumption is that in this
+    situation, the local administrator will handle the situation."""
+    X11_displays_done = set()
+
+    autorandr_binary = os.path.abspath(argv[0])
+
+    for directory in os.listdir("/proc"):
+        directory = os.path.join("/proc/", directory)
+        if not os.path.isdir(directory):
+            continue
+        environ_file = os.path.join(directory, "environ")
+        if not os.path.isfile(environ_file):
+            continue
+        uid = os.stat(environ_file).st_uid
+        if uid == 0:
+            continue
+
+        process_environ = {}
+        for environ_entry in open(environ_file).read().split("\0"):
+            if "=" in environ_entry:
+                name, value = environ_entry.split("=", 1)
+                if name == "DISPLAY" and "." in value:
+                    value = value[:value.find(".")]
+                process_environ[name] = value
+        display = process_environ["DISPLAY"] if "DISPLAY" in process_environ else None
+
+        if display and display not in X11_displays_done:
+            try:
+                pwent = pwd.getpwuid(uid)
+            except KeyError:
+                # User has no pwd entry
+                continue
+
+            print("Running autorandr as %s for display %s" % (pwent.pw_name, display))
+            child_pid = os.fork()
+            if child_pid == 0:
+                # This will throw an exception if any of the privilege changes fails,
+                # so it should be safe. Also, note that since the environment
+                # is taken from a process owned by the user, reusing it should
+                # not leak any information.
+                os.setgroups([])
+                os.setresgid(pwent.pw_gid, pwent.pw_gid, pwent.pw_gid)
+                os.setresuid(pwent.pw_uid, pwent.pw_uid, pwent.pw_uid)
+                os.chdir(pwent.pw_dir)
+                os.environ.clear()
+                os.environ.update(process_environ)
+                os.execl(autorandr_binary, autorandr_binary, *argv[1:])
+                os.exit(1)
+            os.waitpid(child_pid, 0)
+
+            X11_displays_done.add(display)
 
 def main(argv):
     try:
-       options = dict(getopt.getopt(argv[1:], "s:l:d:cfh", [ "dry-run", "change", "default=", "save=", "load=", "force", "fingerprint", "config", "help" ])[0])
+        options = dict(getopt.getopt(argv[1:], "s:r:l:d:cfh", [ "batch", "dry-run", "change", "default=", "save=", "remove=", "load=", "force", "fingerprint", "config", "debug", "skip-options=", "help" ])[0])
     except getopt.GetoptError as e:
-        print(str(e))
-        options = { "--help": True }
+        print("Failed to parse options: {0}.\n"
+              "Use --help to get usage information.".format(str(e)),
+              file=sys.stderr)
+        sys.exit(posix.EX_USAGE)
+
+    # Batch mode
+    if "--batch" in options:
+        if ("DISPLAY" not in os.environ or not os.environ["DISPLAY"]) and os.getuid() == 0:
+            dispatch_call_to_sessions([ x for x in argv if x != "--batch" ])
+        else:
+            print("--batch mode can only be used by root and if $DISPLAY is unset")
+        return
 
     profiles = {}
     try:
         # Load profiles from each XDG config directory
-        for directory in os.environ.get("XDG_CONFIG_DIRS", "").split(":"):
+        # The XDG spec says that earlier entries should take precedence, so reverse the order
+        for directory in reversed(os.environ.get("XDG_CONFIG_DIRS", "/etc/xdg").split(":")):
             system_profile_path = os.path.join(directory, "autorandr")
             if os.path.isdir(system_profile_path):
                 profiles.update(load_profiles(system_profile_path))
@@ -639,18 +873,55 @@ def main(argv):
         output_configuration(config, sys.stdout)
         sys.exit(0)
 
+    if "--skip-options" in options:
+        skip_options = [ y[2:] if y[:2] == "--" else y for y in ( x.strip() for x in options["--skip-options"].split(",") ) ]
+        for profile in profiles.values():
+            for output in profile["config"].values():
+                output.set_ignored_options(skip_options)
+        for output in config.values():
+            output.set_ignored_options(skip_options)
+
     if "-s" in options:
         options["--save"] = options["-s"]
     if "--save" in options:
         if options["--save"] in ( x[0] for x in virtual_profiles ):
             raise AutorandrException("Cannot save current configuration as profile '%s':\nThis configuration name is a reserved virtual configuration." % options["--save"])
         try:
-            save_configuration(os.path.join(profile_path, options["--save"]), config)
+            profile_folder = os.path.join(profile_path, options["--save"])
+            save_configuration(profile_folder, config)
+            exec_scripts(profile_folder, "postsave", {"CURRENT_PROFILE": options["--save"], "PROFILE_FOLDER": profile_folder})
         except Exception as e:
             raise AutorandrException("Failed to save current configuration as profile '%s'" % (options["--save"],), e)
         print("Saved current configuration as profile '%s'" % options["--save"])
         sys.exit(0)
 
+    if "-r" in options:
+        options["--remove"] = options["-r"]
+    if "--remove" in options:
+        if options["--remove"] in ( x[0] for x in virtual_profiles ):
+            raise AutorandrException("Cannot remove profile '%s':\nThis configuration name is a reserved virtual configuration." % options["--remove"])
+        if options["--remove"] not in profiles.keys():
+            raise AutorandrException("Cannot remove profile '%s':\nThis profile does not exist." % options["--remove"])
+        try:
+            remove = True
+            profile_folder = os.path.join(profile_path, options["--remove"])
+            profile_dirlist = os.listdir(profile_folder)
+            profile_dirlist.remove("config")
+            profile_dirlist.remove("setup")
+            if profile_dirlist:
+                print("Profile folder '%s' contains the following additional files:\n---\n%s\n---" % (options["--remove"], "\n".join(profile_dirlist)))
+                response = input("Do you really want to remove profile '%s'? If so, type 'yes': " % options["--remove"]).strip()
+                if response != "yes":
+                    remove = False
+            if remove is True:
+                shutil.rmtree(profile_folder)
+                print("Removed profile '%s'" % options["--remove"])
+            else:
+                print("Profile '%s' was not removed" % options["--remove"])
+        except Exception as e:
+            raise AutorandrException("Failed to remove profile '%s'" % (options["--remove"],), e)
+        sys.exit(0)
+
     if "-h" in options or "--help" in options:
         exit_help()
 
@@ -662,16 +933,31 @@ def main(argv):
     if "--load" in options:
         load_profile = options["--load"]
     else:
+        # Find the active profile(s) first, for the block script (See #42)
+        current_profiles = []
         for profile_name in profiles.keys():
-            if profile_blocked(os.path.join(profile_path, profile_name)):
+            configs_are_equal = is_equal_configuration(config, profiles[profile_name]["config"])
+            if configs_are_equal:
+                current_profiles.append(profile_name)
+        block_script_metadata = {
+            "CURRENT_PROFILE":  "".join(current_profiles[:1]),
+            "CURRENT_PROFILES": ":".join(current_profiles)
+        }
+
+        for profile_name in profiles.keys():
+            if profile_blocked(os.path.join(profile_path, profile_name), block_script_metadata):
                 print("%s (blocked)" % profile_name, file=sys.stderr)
                 continue
+            props = []
             if profile_name in detected_profiles:
-                print("%s (detected)" % profile_name, file=sys.stderr)
+                props.append("(detected)")
                 if ("-c" in options or "--change" in options) and not load_profile:
                     load_profile = profile_name
-            else:
-                print(profile_name, file=sys.stderr)
+            if profile_name in current_profiles:
+                props.append("(current)")
+            print("%s%s%s" % (profile_name, " " if props else "", " ".join(props)), file=sys.stderr)
+            if not configs_are_equal and "--debug" in options and profile_name in detected_profiles:
+                print_profile_differences(config, profiles[profile_name]["config"])
 
     if "-d" in options:
         options["--default"] = options["-d"]
@@ -695,30 +981,47 @@ def main(argv):
         if load_config == dict(config) and not "-f" in options and not "--force" in options:
             print("Config already loaded", file=sys.stderr)
             sys.exit(0)
+        if "--debug" in options and load_config != dict(config):
+            print("Loading profile '%s'" % load_profile)
+            print_profile_differences(config, load_config)
+
         remove_irrelevant_outputs(config, load_config)
 
         try:
             if "--dry-run" in options:
                 apply_configuration(load_config, config, True)
             else:
-                exec_scripts(scripts_path, "preswitch")
+                script_metadata = {
+                    "CURRENT_PROFILE": load_profile,
+                    "PROFILE_FOLDER": scripts_path,
+                }
+                exec_scripts(scripts_path, "preswitch", script_metadata)
+                if "--debug" in options:
+                    print("Going to run:")
+                    apply_configuration(load_config, config, True)
                 apply_configuration(load_config, config, False)
-                exec_scripts(scripts_path, "postswitch")
+                exec_scripts(scripts_path, "postswitch", script_metadata)
         except Exception as e:
             raise AutorandrException("Failed to apply profile '%s'" % load_profile, e, True)
 
+        if "--dry-run" not in options and "--debug" in options:
+            new_config, _ = parse_xrandr_output()
+            if not is_equal_configuration(new_config, load_config):
+                print("The configuration change did not go as expected:")
+                print_profile_differences(new_config, load_config)
+
     sys.exit(0)
 
 if __name__ == '__main__':
     try:
         main(sys.argv)
     except AutorandrException as e:
-        print(file=sys.stderr)
         print(e, file=sys.stderr)
         sys.exit(1)
     except Exception as e:
-        trace = sys.exc_info()[2]
-        while trace.tb_next:
-            trace = trace.tb_next
-            print("\nUnhandled exception in line %d. Please report this as a bug:\n  %s" % (trace.tb_lineno, "\n  ".join(str(e).split("\n")),), file=sys.stderr)
-        sys.exit(1)
+        if not len(str(e)):  # BdbQuit
+            print("Exception: {0}".format(e.__class__.__name__))
+            sys.exit(2)
+
+        print("Unhandled exception ({0}). Please report this as a bug at https://github.com/phillipberndt/autorandr/issues.".format(e), file=sys.stderr)
+        raise