| # Copyright 2016 The Chromium Authors. All rights reserved. |
| # Use of this source code is governed by a BSD-style license that can be |
| # found in the LICENSE file. |
| import math |
| import json |
| |
| |
| class ParsedTraceEvents(object): |
| def __init__(self, events = None, trace_filename = None): |
| """ |
| Utility class for filtering and manipulating trace data. |
| |
| events -- An iterable object containing trace events |
| trace_filename -- A file object that contains a complete trace. |
| |
| """ |
| if trace_filename and events: |
| raise Exception("Provide either a trace file or event list") |
| if not trace_filename and events == None: |
| raise Exception("Provide either a trace file or event list") |
| |
| if trace_filename: |
| f = open(trace_filename, 'r') |
| t = f.read() |
| f.close() |
| |
| # If the event data begins with a [, then we know it should end with a ]. |
| # The reason we check for this is because some tracing implementations |
| # cannot guarantee that a ']' gets written to the trace file. So, we are |
| # forgiving and if this is obviously the case, we fix it up before |
| # throwing the string at JSON.parse. |
| if t[0] == '[': |
| n = len(t); |
| if t[n - 1] != ']' and t[n - 1] != '\n': |
| t = t + ']' |
| elif t[n - 2] != ']' and t[n - 1] == '\n': |
| t = t + ']' |
| elif t[n - 3] != ']' and t[n - 2] == '\r' and t[n - 1] == '\n': |
| t = t + ']' |
| |
| try: |
| events = json.loads(t) |
| except ValueError: |
| raise Exception("Corrupt trace, did not parse. Value: %s" % t) |
| |
| if 'traceEvents' in events: |
| events = events['traceEvents'] |
| |
| if not hasattr(events, '__iter__'): |
| raise Exception, 'events must be iteraable.' |
| self.events = events |
| self.pids = None |
| self.tids = None |
| |
| def __len__(self): |
| return len(self.events) |
| |
| def __getitem__(self, i): |
| return self.events[i] |
| |
| def __setitem__(self, i, v): |
| self.events[i] = v |
| |
| def __repr__(self): |
| return "[%s]" % ",\n ".join([repr(e) for e in self.events]) |
| |
| def findProcessIds(self): |
| if self.pids: |
| return self.pids |
| pids = set() |
| for e in self.events: |
| if "pid" in e and e["pid"]: |
| pids.add(e["pid"]) |
| self.pids = list(pids) |
| return self.pids |
| |
| def findThreadIds(self): |
| if self.tids: |
| return self.tids |
| tids = set() |
| for e in self.events: |
| if "tid" in e and e["tid"]: |
| tids.add(e["tid"]) |
| self.tids = list(tids) |
| return self.tids |
| |
| def findEventsOnProcess(self, pid): |
| return ParsedTraceEvents([e for e in self.events if e["pid"] == pid]) |
| |
| def findEventsOnThread(self, tid): |
| return ParsedTraceEvents( |
| [e for e in self.events if e["ph"] != "M" and e["tid"] == tid]) |
| |
| def findByPhase(self, ph): |
| return ParsedTraceEvents([e for e in self.events if e["ph"] == ph]) |
| |
| def findByName(self, n): |
| return ParsedTraceEvents([e for e in self.events if e["name"] == n]) |
