tools: add performance-log-close-tags.py, use in performance-log-viewer

Add a new performance-log-close-tags.py tool, which closes unclosed
tags in incomplete performance logs, allowing the rest of the
perofmance-log tools to process them.  This is necessary for
unfinished progressive logs.

Use the new tool as part of the pipeline in performance-log-viewer.

tools/Makefile.am

@@ -100,6 +100,7 @@ EXTRA_DIST = \
 	gimp-mkenums			\
 	gimppath2svg.py			\
 	mnemonic-clashes		\
+	performance-log-close-tags.py	\
 	performance-log-coalesce.py	\
 	performance-log-deduce.py	\
 	performance-log-expand.py	\

tools/performance-log-close-tags.py

@@ -0,0 +1,49 @@
+#!/usr/bin/env python3
+
+"""
+performance-log-close-tags.py -- Closes open tags in GIMP performance logs
+Copyright (C) 2020  Ell
+
+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 <https://www.gnu.org/licenses/>.
+
+
+Usage: performance-log-close-tags.py < infile > outfile
+"""
+
+from xml.etree import ElementTree
+import sys
+
+class OpenTagsTracker:
+    open_tags = []
+
+    def start (self, tag, attrib):
+        self.open_tags.append (tag)
+
+    def end (self, tag):
+        self.open_tags.pop ()
+
+# Read performance log from STDIN
+text = sys.stdin.buffer.read ()
+
+# Write performance log to STDOUT
+sys.stdout.buffer.write (text)
+
+# Track open tags
+tracker = OpenTagsTracker ()
+
+ElementTree.XMLParser (target = tracker).feed (text)
+
+# Close remaining open tags
+for tag in reversed (tracker.open_tags):
+    print ("</%s>" % tag)

tools/performance-log-viewer

@@ -30,8 +30,9 @@ file="$1"
 
 < "$file" || exit 1
 
-< "$file"                                  \
-"$tools_dir/performance-log-expand.py"   | \
-"$tools_dir/performance-log-coalesce.py" | \
-"$tools_dir/performance-log-deduce.py"   | \
+< "$file"                                    \
+"$tools_dir/performance-log-close-tags.py" | \
+"$tools_dir/performance-log-expand.py"     | \
+"$tools_dir/performance-log-coalesce.py"   | \
+"$tools_dir/performance-log-deduce.py"     | \
 "$tools_dir/performance-log-viewer.py"