test/py: support TABs in log

Wrap all logged stream content with <pre>. This allows TABs to work as
expected, so this commit stops converting TABs to "escape" sequences. It
also means that we don't have to:
- Convert spaces to &nbsp;.
- Convert newlines to<br/>.
- Manually check whether the last line of a stream ended with a newline
  or not in order to prevent the next "heading" from merging with the
  previous line.

The default CSS style for <pre> seems to include a top/bottom margin that
we don't want, so modify the CSS style sheet to remove this. This keeps
the spacing/layout of the HTML log file the same before/after this change.

Signed-off-by: Stephen Warren <swarren@nvidia.com>

test/py/multiplexed_log.css

@@ -9,6 +9,11 @@ body {
     color: #ffffff;
 }
 
+pre {
+    margin-top: 0px;
+    margin-bottom: 0px;
+}
+
 .implicit {
     color: #808080;
 }

test/py/multiplexed_log.py

@@ -73,7 +73,6 @@ class Logfile(object):
     def __init__(self, fn):
         self.f = open(fn, "wt")
         self.last_stream = None
-        self.linebreak = True
         self.blocks = []
         self.cur_evt = 1
         shutil.copy(mod_dir + "/multiplexed_log.css", os.path.dirname(fn))
@@ -99,17 +98,13 @@ def _escape(self, data):
         data = "".join((c in self._nonprint) and ("%%%02x" % ord(c)) or
                        c for c in data)
         data = cgi.escape(data)
-        data = data.replace(" ", " ")
-        self.linebreak = data[-1:-1] == "\n"
-        data = data.replace(chr(10), "<br/>\n")
         return data
 
     def _terminate_stream(self):
         self.cur_evt += 1
         if not self.last_stream:
             return
-        if not self.linebreak:
-            self.f.write("<br/>\n")
+        self.f.write("</pre>\n")
         self.f.write("<div class=\"stream-trailer\" id=\"" +
                      self.last_stream.name + "\">End stream: " +
                      self.last_stream.name + "</div>\n")
@@ -120,9 +115,8 @@ def _note(self, note_type, msg):
         self._terminate_stream()
         self.f.write("<div class=\"" + note_type + "\">\n")
         self.f.write(self._escape(msg))
-        self.f.write("<br/>\n")
+        self.f.write("\n")
         self.f.write("</div>\n")
-        self.linebreak = True
 
     def start_section(self, marker):
         self._terminate_stream()
@@ -173,7 +167,7 @@ def get_stream(self, name, chained_file=None):
     def get_runner(self, name, chained_file=None):
         return RunAndLog(self, name, chained_file)
 
-    _nonprint = ("^%" + "".join(chr(c) for c in range(0, 32) if c != 10) +
+    _nonprint = ("^%" + "".join(chr(c) for c in range(0, 32) if c not in (9, 10)) +
                  "".join(chr(c) for c in range(127, 256)))
 
     def write(self, stream, data, implicit=False):
@@ -182,6 +176,7 @@ def write(self, stream, data, implicit=False):
             self.f.write("<div class=\"stream\" id=\"%s\">\n" % stream.name)
             self.f.write("<div class=\"stream-header\" id=\"" + stream.name +
                          "\">Stream: " + stream.name + "</div>\n")
+            self.f.write("<pre>")
         if implicit:
             self.f.write("<span class=\"implicit\">")
         self.f.write(self._escape(data))