Add a portage_debug module and python-trace feature for --debug mode.

svn path=/main/trunk/; revision=2979

3 files changed, 124 insertions, 0 deletions

diff --git a/bin/ebuild b/bin/ebuild
index fafdbbcc..a62585a5 100755
--- a/bin/ebuild
+++ b/bin/ebuild
@@ -25,6 +25,11 @@ sys.path = ["/usr/lib/portage/pym"]+sys.path
 
 import portage, portage_util, portage_const
 
+# do this _after_ 'import portage' to prevent unnecessary tracing
+if debug and "python-trace" in portage.features:
+	import portage_debug
+	portage_debug.set_trace(True)
+
 if portage.settings["NOCOLOR"] in ("yes","true") or not sys.stdout.isatty():
 	import output
 	output.nocolor()
diff --git a/bin/emerge b/bin/emerge
index b17a2a6b..55e9420d 100755
--- a/bin/emerge
+++ b/bin/emerge
@@ -401,6 +401,9 @@ if ("--debug" in myopts):
 	portage.settings.backup_changes("PORTAGE_DEBUG")
 	portage.debug=1
 	portage.settings.lock()
+	if "python-trace" in portage.features:
+		import portage_debug
+		portage_debug.set_trace(True)
 
 if ("--resume" in myopts):
 	if "--tree" in myopts:
diff --git a/pym/portage_debug.py b/pym/portage_debug.py
new file mode 100644
index 00000000..318754d7
--- /dev/null
+++ b/pym/portage_debug.py
@@ -0,0 +1,116 @@
+# Copyright 1999-2006 Gentoo Foundation
+# Distributed under the terms of the GNU General Public License v2
+# $Header: $
+
+import os, sys, threading
+
+import portage_const
+from portage_util import writemsg
+
+def set_trace(on=True):
+	if on:
+		t = trace_handler()
+		threading.settrace(t.event_handler)
+		sys.settrace(t.event_handler)
+	else:
+		sys.settrace(None)
+		threading.settrace(None)
+
+class trace_handler(object):
+
+	def __init__(self):
+		python_base = None
+		for x in sys.path:
+			if os.path.basename(x).startswith("python2."):
+				python_base = x
+				break
+
+		self.ignore_prefixes = []
+		if python_base is not None:
+			self.ignore_prefixes.append(python_base + os.sep)
+
+		self.trim_filename = prefix_trimmer(os.path.join(portage_const.PORTAGE_BASE_PATH, "pym") + os.sep).trim
+		self.show_local_lines = False
+		self.max_repr_length = 200
+
+	def event_handler(self, *args):
+		frame, event, arg = args
+		if "line" == event:
+			if self.show_local_lines:
+				self.trace_line(*args)
+		else:
+			if not self.ignore_filename(frame.f_code.co_filename):
+				self.trace_event(*args)
+				return self.event_handler
+
+	def trace_event(self, frame, event, arg):
+		writemsg("%s line=%d name=%s event=%s %slocals=%s\n" % \
+		(self.trim_filename(frame.f_code.co_filename),
+		frame.f_lineno,
+		frame.f_code.co_name,
+		event,
+		self.arg_repr(frame, event, arg),
+		self.locals_repr(frame, event, arg)))
+
+	def arg_repr(self, frame, event, arg):
+		my_repr = None
+		if "return" == event:
+			my_repr = repr(arg)
+			if len(my_repr) > self.max_repr_length:
+				my_repr = "'omitted'"
+			return "value=%s " % my_repr
+		elif "exception" == event:
+			my_repr = repr(arg[1])
+			if len(my_repr) > self.max_repr_length:
+				my_repr = "'omitted'"
+			return "type=%s value=%s " % (arg[0], my_repr)
+
+		return ""
+
+	def trace_line(self, frame, event, arg):
+		writemsg("%s line=%d\n" % (self.trim_filename(frame.f_code.co_filename), frame.f_lineno))
+
+	def ignore_filename(self, filename):
+		if filename:
+			for x in self.ignore_prefixes:
+				if filename.startswith(x):
+					return True
+		return False
+
+	def locals_repr(self, frame, event, arg):
+		"""Create a representation of the locals dict that is suitable for
+		tracing output."""
+
+		my_locals = frame.f_locals.copy()
+
+		# prevent unsafe  __repr__ call on self when __init__ is called
+		# (method calls aren't safe until after __init__  has completed).
+		if frame.f_code.co_name == "__init__" and "self" in my_locals:
+			my_locals["self"] = "omitted"
+
+		# We omit items that will lead to unreasonable bloat of the trace
+		# output (and resulting log file).
+		for k, v in my_locals.iteritems():
+			my_repr = repr(v)
+			if len(my_repr) > self.max_repr_length:
+				my_locals[k] = "omitted"
+		return my_locals
+
+class prefix_trimmer(object):
+	def __init__(self, prefix):
+		self.prefix = prefix
+		self.cut_index = len(prefix)
+		self.previous = None
+		self.previous_trimmed = None
+
+	def trim(self, s):
+		"""Remove a prefix from the string and return the result.
+		The previous result is automatically cached."""
+		if s == self.previous:
+			return self.previous_trimmed
+		else:
+			if s.startswith(self.prefix):
+				self.previous_trimmed = s[self.cut_index:]
+			else:
+				self.previous_trimmed = s
+			return self.previous_trimmed