Tarball conversion

1 files changed, 96 insertions, 0 deletions

diff --git a/bzrlib/strace.py b/bzrlib/strace.py
new file mode 100644
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+++ b/bzrlib/strace.py
@@ -0,0 +1,96 @@
+# Copyright (C) 2007, 2009, 2010 Canonical Ltd
+#   Authors: Robert Collins <robert.collins@canonical.com>
+#
+# 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 2 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, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+
+"""Support for running strace against the current process."""
+
+from __future__ import absolute_import
+
+import os
+import signal
+import subprocess
+import tempfile
+
+from bzrlib import errors
+
+
+def strace(function, *args, **kwargs):
+    """Invoke strace on function.
+
+    :return: a tuple: function-result, a StraceResult.
+    """
+    return strace_detailed(function, args, kwargs)
+
+
+def strace_detailed(function, args, kwargs, follow_children=True):
+    # FIXME: strace is buggy
+    # (https://bugs.launchpad.net/ubuntu/+source/strace/+bug/103133) and the
+    # test suite hangs if the '-f' is given to strace *and* more than one
+    # thread is running. Using follow_children=False allows the test suite to
+    # disable fork following to work around the bug.
+
+    # capture strace output to a file
+    log_file = tempfile.NamedTemporaryFile()
+    log_file_fd = log_file.fileno()
+    err_file = tempfile.NamedTemporaryFile()
+    pid = os.getpid()
+    # start strace
+    strace_cmd = ['strace', '-r', '-tt', '-p', str(pid), '-o', log_file.name]
+    if follow_children:
+        strace_cmd.append('-f')
+    # need to catch both stdout and stderr to work around
+    # bug 627208
+    proc = subprocess.Popen(strace_cmd,
+                            stdout=subprocess.PIPE,
+                            stderr=err_file.fileno())
+    # Wait for strace to attach
+    attached_notice = proc.stdout.readline()
+    # Run the function to strace
+    result = function(*args, **kwargs)
+    # stop strace
+    os.kill(proc.pid, signal.SIGQUIT)
+    proc.communicate()
+    # grab the log
+    log_file.seek(0)
+    log = log_file.read()
+    log_file.close()
+    # and stderr
+    err_file.seek(0)
+    err_messages = err_file.read()
+    err_file.close()
+    # and read any errors
+    if err_messages.startswith("attach: ptrace(PTRACE_ATTACH,"):
+        raise StraceError(err_messages=err_messages)
+    return result, StraceResult(log, err_messages)
+
+
+class StraceError(errors.BzrError):
+    
+    _fmt = "strace failed: %(err_messages)s"
+
+
+class StraceResult(object):
+    """The result of stracing a function."""
+
+    def __init__(self, raw_log, err_messages):
+        """Create a StraceResult.
+
+        :param raw_log: The output that strace created.
+        """
+        self.raw_log = raw_log
+        self.err_messages = err_messages
+
+