Mercurial > hg
view mercurial/lsprofcalltree.py @ 26375:3686fa2b8eee
windows: insert file positioning call between reads and writes
fopen() and fdopen() have a unique-to-Windows requirement that
transitions between read and write operations in files opened
in modes r+, w+, and a+ perform a file positioning call
(fsetpos, fseek, or rewind) in between. While the MSDN docs don't
say what will happen if this is not done, observations reveal
that Python raises an IOError with errno 0. Furthermore, I
/think/ this behavior isn't deterministic. But I can reproduce
it reliably with subsequent patches applied that open revlogs
in a+ mode and perform both reads and writes.
This patch introduces a proxy class for file handles opened
in r+, w+, and a+ mode on Windows. The class intercepts calls
and audits whether a file positioning function has been called
between read and write operations. If not, a dummy, no-op seek
to the current file position is performed. This appears to be
sufficient to "trick" Windows into allowing transitions between
read and writes without raising errors.
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Sun, 27 Sep 2015 18:46:53 -0700 |
parents | beae42f3d93b |
children | 071af8d385a9 |
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""" lsprofcalltree.py - lsprof output which is readable by kcachegrind Authors: * David Allouche <david <at> allouche.net> * Jp Calderone & Itamar Shtull-Trauring * Johan Dahlin This software may be used and distributed according to the terms of the GNU General Public License, incorporated herein by reference. """ def label(code): if isinstance(code, str): return '~' + code # built-in functions ('~' sorts at the end) else: return '%s %s:%d' % (code.co_name, code.co_filename, code.co_firstlineno) class KCacheGrind(object): def __init__(self, profiler): self.data = profiler.getstats() self.out_file = None def output(self, out_file): self.out_file = out_file print >> out_file, 'events: Ticks' self._print_summary() for entry in self.data: self._entry(entry) def _print_summary(self): max_cost = 0 for entry in self.data: totaltime = int(entry.totaltime * 1000) max_cost = max(max_cost, totaltime) print >> self.out_file, 'summary: %d' % (max_cost,) def _entry(self, entry): out_file = self.out_file code = entry.code #print >> out_file, 'ob=%s' % (code.co_filename,) if isinstance(code, str): print >> out_file, 'fi=~' else: print >> out_file, 'fi=%s' % (code.co_filename,) print >> out_file, 'fn=%s' % (label(code),) inlinetime = int(entry.inlinetime * 1000) if isinstance(code, str): print >> out_file, '0 ', inlinetime else: print >> out_file, '%d %d' % (code.co_firstlineno, inlinetime) # recursive calls are counted in entry.calls if entry.calls: calls = entry.calls else: calls = [] if isinstance(code, str): lineno = 0 else: lineno = code.co_firstlineno for subentry in calls: self._subentry(lineno, subentry) print >> out_file def _subentry(self, lineno, subentry): out_file = self.out_file code = subentry.code #print >> out_file, 'cob=%s' % (code.co_filename,) print >> out_file, 'cfn=%s' % (label(code),) if isinstance(code, str): print >> out_file, 'cfi=~' print >> out_file, 'calls=%d 0' % (subentry.callcount,) else: print >> out_file, 'cfi=%s' % (code.co_filename,) print >> out_file, 'calls=%d %d' % ( subentry.callcount, code.co_firstlineno) totaltime = int(subentry.totaltime * 1000) print >> out_file, '%d %d' % (lineno, totaltime)