Change comment handling for long lines in url_sig plugin (apache#7421)

 Change comment handling for long lines

There is a 300char max buffer size on lines url sig. If there is a comment longer than this then it will show up in the next fgets. If that happens to contain an `=` then it may end up being parsed as a rule otherwise it is thrown away but has an error printed.
This changes the comment handling so that if there is no `\n` seen at the end of the string in the buffer then it is assumed it is a long comment line and urlsig will continue eating the buffer until it hits a `\n`

plugins/experimental/url_sig/url_sig.c

@@ -135,14 +135,27 @@ TSRemapNewInstance(int argc, char *argv[], void **ih, char *errbuf, int errbuf_s
   char line[300];
   int line_no = 0;
   int keynum;
+  bool eat_comment = false;
 
   cfg = TSmalloc(sizeof(struct config));
   memset(cfg, 0, sizeof(struct config));
 
   while (fgets(line, sizeof(line), file) != NULL) {
     TSDebug(PLUGIN_NAME, "LINE: %s (%d)", line, (int)strlen(line));
     line_no++;
+
+    if (eat_comment) {
+      // Check if final char is EOL, if so we are done eating
+      if (line[strlen(line) - 1] == '\n') {
+        eat_comment = false;
+      }
+      continue;
+    }
     if (line[0] == '#' || strlen(line) <= 1) {
+      // Check if we have a comment longer than the full buffer if no EOL
+      if (line[strlen(line) - 1] != '\n') {
+        eat_comment = true;
+      }
       continue;
     }
     char *pos = strchr(line, '=');

tests/gold_tests/pluginTest/url_sig/url_sig.config

@@ -1,3 +1,4 @@
+#This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line. This is a very long test line.
 key0 = hV3wqyq1QxJeF76JkzHf93tuLYv_abw5
 key1 = nIpyXbVqPFVN7y8yMlfgFBLnOqDSufMy
 key2 = 4UED1ELmHkEcXrS_7yEYPKtgUZdGWaP2

tests/gold_tests/pluginTest/url_sig/url_sig.test.py

@@ -264,3 +264,4 @@ def sign(payload, key):
 
 # Overriding the built in ERROR check since we expect some ERROR messages
 ts.Disk.diags_log.Content = Testers.ContainsExpression("ERROR", "Some tests are failure tests")
+ts.Disk.diags_log.Content += Testers.ExcludesExpression("Error parsing", "Verify that we can accept long comment lines")