gstreamer/debug-viewer/GstDebugViewer/Data.py

# -*- coding: utf-8; mode: python; -*-
#
#  GStreamer Debug Viewer - View and analyze GStreamer debug log files
#
#  Copyright (C) 2007 René Stadler <mail@renestadler.de>
#
#  This program is free software; you can redistribute it and/or modify it
#  under the terms of the GNU General Public License as published by the Free
#  Software Foundation; either version 3 of the License, or (at your option)
#  any later version.
#
#  This program 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 General Public License for
#  more details.
#
#  You should have received a copy of the GNU General Public License along with
#  this program.  If not, see <http://www.gnu.org/licenses/>.

"""GStreamer Debug Viewer Data module."""

import os
import logging
import re

# Nanosecond resolution (like gst.SECOND)
SECOND = 1000000000

def time_args (ts):

    secs = ts // SECOND

    return "%i:%02i:%02i.%09i" % (secs // 60**2,
                                  secs // 60 % 60,
                                  secs % 60,
                                  ts % SECOND,)

def time_diff_args (time_diff):

    if time_diff >= 0:
        sign = "+"
    else:
        sign = "-"

    secs = abs (time_diff) // SECOND

    return "%s%02i:%02i.%09i" % (sign,
                                 secs // 60,
                                 secs % 60,
                                 abs (time_diff) % SECOND,)

def time_args_no_hours (ts):

    secs = ts // SECOND

    return "%02i:%02i.%09i" % (secs // 60,
                               secs % 60,
                               ts % SECOND,)

def parse_time (st):

    """Parse time strings that look like "0:00:00.0000000"."""

    h, m, s = st.split (":")
    secs, subsecs = s.split (".")

    return (long ((int (h) * 60**2 + int (m) * 60) * SECOND) +
            long (secs) * SECOND + long (subsecs))

class DebugLevel (int):

    __names = ["NONE", "ERROR", "WARN", "INFO", "DEBUG", "LOG", "FIXME", "TRACE"]
    __instances = {}

    def __new__ (cls, level):

        try:
            level_int = int (level)
        except (ValueError, TypeError,):
            try:
                level_int = cls.__names.index (level.upper ())
            except ValueError:
                raise ValueError ("no debug level named %r" % (level,))
        if level_int in cls.__instances:
            return cls.__instances[level_int]
        else:
            new_instance = int.__new__ (cls, level_int)
            new_instance.name = cls.__names[level_int]
            cls.__instances[level_int] = new_instance
            return new_instance

    def __repr__ (self):

        return "<%s %s (%i)>" % (type (self).__name__, self.__names[self], self,)

    def higher_level (self):

        if self == len (self.__names) - 1:
            raise ValueError ("already the highest debug level")

        return DebugLevel (self + 1)

    def lower_level (self):

        if self == 0:
            raise ValueError ("already the lowest debug level")

        return DebugLevel (self - 1)

debug_level_none = DebugLevel ("NONE")
debug_level_error = DebugLevel ("ERROR")
debug_level_warning = DebugLevel ("WARN")
debug_level_info = DebugLevel ("INFO")
debug_level_debug = DebugLevel ("DEBUG")
debug_level_log = DebugLevel ("LOG")
debug_level_fixme = DebugLevel ("FIXME")
debug_level_trace = DebugLevel ("TRACE")
debug_levels = [debug_level_none,
                debug_level_trace,
                debug_level_fixme,
                debug_level_log,
                debug_level_debug,
                debug_level_info,
                debug_level_warning,
                debug_level_error]

# For stripping color codes:
_escape = re.compile ("\x1b\\[[0-9;]*m")
def strip_escape (s):

    # FIXME: This can be optimized further!

    while "\x1b" in s:
        s = _escape.sub ("", s)
    return s

def default_log_line_regex_ ():

    # "DEBUG             "
    LEVEL = "([A-Z]+)\s+"
    # "0x8165430 "
    THREAD = r"(0x[0-9a-f]+)\s+" #r"\((0x[0-9a-f]+) - "
    # "0:00:00.777913000  "
    TIME = r"(\d+:\d\d:\d\d\.\d+)\s+"
    CATEGORY = "([A-Za-z0-9_-]+)\s+" # "GST_REFCOUNTING ", "flacdec "
    # "  3089 "
    PID = r"(\d+)\s*"
    FILENAME = r"([^:]*):"
    LINE = r"(\d+):"
    FUNCTION = "([A-Za-z0-9_]*):"
    # FIXME: When non-g(st)object stuff is logged with *_OBJECT (like
    # buffers!), the address is printed *without* <> brackets!
    OBJECT = "(?:<([^>]+)>)?"
    MESSAGE = "(.+)"

    ANSI = "(?:\x1b\\[[0-9;]*m\\s*)*\\s*"

    # New log format:
    expressions = [TIME, ANSI, PID, ANSI, THREAD, ANSI, LEVEL, ANSI,
                   CATEGORY, FILENAME, LINE, FUNCTION, ANSI,
                   OBJECT, ANSI, MESSAGE]
    # Old log format:
    ## expressions = [LEVEL, THREAD, TIME, CATEGORY, PID, FILENAME, LINE,
    ##                FUNCTION, OBJECT, MESSAGE]

    return expressions

def default_log_line_regex ():

    expressions = default_log_line_regex_ ()
    return re.compile ("".join (expressions))

class Producer (object):

    def __init__ (self):

        self.consumers = []

    def have_load_started (self):

        for consumer in self.consumers:
            consumer.handle_load_started ()

    def have_load_finished (self):

        for consumer in self.consumers:
            consumer.handle_load_finished ()

class SortHelper (object):

    def __init__ (self, fileobj, offsets):

        self._gen = self.__gen (fileobj, offsets)
        self._gen.next ()

        # Override in the instance, for performance (this gets called in an
        # inner loop):
        self.find_insert_position = self._gen.send

    @staticmethod
    def find_insert_position (insert_time_string):

        # Stub for documentary purposes.

        pass

    @staticmethod
    def __gen (fileobj, offsets):

        from math import floor
        tell = fileobj.tell
        seek = fileobj.seek
        read = fileobj.read
        time_len = len (time_args (0))

        # We remember the previous insertion point. This gives a nice speed up
        # for larger bubbles which are already sorted. TODO: In practice, log
        # lines only get out of order across threads. Need to check if it pays
        # to parse the thread here and maintain multiple insertion points for
        # heavily interleaved parts of the log.
        pos = 0
        pos_time_string = ""

        insert_pos = None
        while True:
            insert_time_string = (yield insert_pos)

            save_offset = tell ()

            if pos_time_string <= insert_time_string:
                lo = pos
                hi = len (offsets)
            else:
                lo = 0
                hi = pos

            # This is a bisection search, except we don't cut the range in the
            # middle each time, but at the 90th percentile. This is because
            # logs are "mostly sorted", so the insertion point is much more
            # likely to be at the end anyways:
            while lo < hi:
                mid = int (floor (lo * 0.1 + hi * 0.9))
                seek (offsets[mid])
                mid_time_string = read (time_len)
                if insert_time_string < mid_time_string:
                    hi = mid
                else:
                    lo = mid + 1
            pos = lo
            # Caller will replace row at pos with the new one, so this is
            # correct:
            pos_time_string = insert_time_string

            insert_pos = pos

            seek (save_offset)

class LineCache (Producer):

    _lines_per_iteration = 50000

    def __init__ (self, fileobj, dispatcher):

        Producer.__init__ (self)

        self.logger = logging.getLogger ("linecache")
        self.dispatcher = dispatcher

        self.__fileobj = fileobj
        self.__fileobj.seek (0, 2)
        self.__file_size = self.__fileobj.tell ()
        self.__fileobj.seek (0)

        self.offsets = []
        self.levels = [] # FIXME

    def start_loading (self):

        self.logger.debug ("dispatching load process")
        self.have_load_started ()
        self.dispatcher (self.__process ())

    def get_progress (self):

        return float (self.__fileobj.tell ()) / self.__file_size

    def __process (self):

        offsets = self.offsets
        levels = self.levels

        dict_levels = {"T" : debug_level_trace, "F" : debug_level_fixme,
                       "L" : debug_level_log, "D" : debug_level_debug,
                       "I" : debug_level_info, "W" : debug_level_warning,
                       "E" : debug_level_error, " " : debug_level_none}
        ANSI = "(?:\x1b\\[[0-9;]*m)?"
        ANSI_PATTERN = (r"\d:\d\d:\d\d\.\d+ " + ANSI +
                        r" *\d+" + ANSI +
                        r" +0x[0-9a-f]+ +" + ANSI +
                        r"([TFLDIEW ])")
        BARE_PATTERN = ANSI_PATTERN.replace (ANSI, "")
        rexp_bare = re.compile (BARE_PATTERN)
        rexp_ansi = re.compile (ANSI_PATTERN)
        rexp = rexp_bare

        # Moving attribute lookups out of the loop:
        readline = self.__fileobj.readline
        tell = self.__fileobj.tell
        rexp_match = rexp.match
        levels_append = levels.append
        offsets_append = offsets.append
        dict_levels_get = dict_levels.get

        self.__fileobj.seek (0)
        limit = self._lines_per_iteration
        last_line = ""
        i = 0
        sort_helper = SortHelper (self.__fileobj, offsets)
        find_insert_position = sort_helper.find_insert_position
        while True:
            i += 1
            if i >= limit:
                i = 0
                yield True

            offset = tell ()
            line = readline ()
            if not line:
                break
            match = rexp_match (line)
            if match is None:
                if rexp is rexp_ansi or not "\x1b" in line:
                    continue

                match = rexp_ansi.match (line)
                if match is None:
                    continue
                # Switch to slower ANSI parsing:
                rexp = rexp_ansi
                rexp_match = rexp.match

            # Timestamp is in the very beginning of the row, and can be sorted
            # by lexical comparison. That's why we don't bother parsing the
            # time to integer. We also don't have to take a substring here,
            # which would be a useless memcpy.
            if line >= last_line:
                levels_append (dict_levels_get (match.group (1), debug_level_none))
                offsets_append (offset)
                last_line = line
            else:
                pos = find_insert_position (line)
                levels.insert (pos, dict_levels_get (match.group (1), debug_level_none))
                offsets.insert (pos, offset)

        self.have_load_finished ()
        yield False

class LogLine (list):

    _line_regex = default_log_line_regex ()

    @classmethod
    def parse_full (cls, line_string):

        match = cls._line_regex.match (line_string)
        if match is None:
            ## raise ValueError ("not a valid log line (%r)" % (line_string,))
            groups = [0, 0, 0, 0, "", "", 0, "", "", 0]
            return cls (groups)

        line = cls (match.groups ())
        # Timestamp.
        line[0] = parse_time (line[0])
        # PID.
        line[1] = int (line[1])
        # Thread.
        line[2] = int (line[2], 16)
        # Level (this is handled in LineCache).
        line[3] = 0
        # Line.
        line[6] = int (line[6])
        # Message start offset.
        line[9] = match.start (9 + 1)

        for col_id in (4,   # COL_CATEGORY
                       5,   # COL_FILENAME
                       7,   # COL_FUNCTION,
                       8,): # COL_OBJECT
            line[col_id] = intern (line[col_id] or "")

        return line

class LogLines (object):

    def __init__ (self, fileobj, line_cache):

        self.__fileobj = fileobj
        self.__line_cache = line_cache

    def __len__ (self):

        return len (self.__line_cache.offsets)

    def __getitem__ (self, line_index):

        offset = self.__line_cache.offsets[line_index]
        self.__fileobj.seek (offset)
        line_string = self.__fileobj.readline ()
        line = LogLine.parse_full (line_string)
        msg = line_string[line[-1]:]
        line[-1] = msg
        return line

    def __iter__ (self):

        l = len (self)
        i = 0
        while i < l:
            yield self[i]
            i += 1

class LogFile (Producer):

    def __init__ (self, filename, dispatcher):

        import mmap

        Producer.__init__ (self)

        self.logger = logging.getLogger ("logfile")

        self.path = os.path.normpath (os.path.abspath (filename))
        self.__real_fileobj = file (filename, "rb")
        self.fileobj = mmap.mmap (self.__real_fileobj.fileno (), 0, access = mmap.ACCESS_READ)
        self.line_cache = LineCache (self.fileobj, dispatcher)
        self.line_cache.consumers.append (self)

    def get_full_line (self, line_index):

        offset = self.line_cache.offsets[line_index]
        self.fileobj.seek (offset)
        line_string = self.fileobj.readline ()
        line = LogLine.parse_full (line_string)
        msg = line_string[line[-1]:]
        line[-1] = msg
        return line

    def start_loading (self):

        self.logger.debug ("starting load")
        self.line_cache.start_loading ()

    def get_load_progress (self):

        return self.line_cache.get_progress ()

    def handle_load_started (self):

        # Chain up to our consumers:
        self.have_load_started ()

    def handle_load_finished (self):

        self.lines = LogLines (self.fileobj, self.line_cache)

        # Chain up to our consumers:
        self.have_load_finished ()