do not allow overriding the header/footer settings for cover pages

This was discovered in #1676, where using a command-line like:

  wkhtmltopdf cover cover.html --header-html header.html page.html output.pdf

would override the settings for the cover page and not apply the
--header-html for the URL page.html. This may be unexpected behavior
for most users, but the manual clearly states that the options FOLLOW
the URL/file name, as in:

  cover <input url/file name> [PAGE OPTION]...
  (page)? <input url/file name> [PAGE OPTION]...

So, in the above example it actually means the following

  URL1: cover cover.html --header-html header.html
  URL2: page.html
  OUT:  output.pdf

To fix this, we parse the other page options for a cover page and
then set the header/footer settings to blank values to ensure that
they are not shown on a cover page.

CHANGELOG.md

@@ -1,5 +1,6 @@
 v0.12.2 (unreleased)
 --------------------
+* **#1676**: do not allow overriding the header/footer settings for cover pages
 * **#1758**: fix corrupt image when output is specified as "-" in wkhtmltoimage on Windows
 * **#1772**: added variable 'isodate' for substitution in headers/footers
 * **#1808**: fix [sitepage] and [sitepages] not working without HTML headers/footers

src/pdf/pdfcommandlineparser.cc

@@ -166,16 +166,20 @@ void PdfCommandLineParser::parseArguments(int argc, const char ** argv, bool fro
 				usage(stderr, false);
 				exit(1);
 			}
-			ps.page = QString::fromLocal8Bit(argv[arg]);
+			ps.page = QString::fromLocal8Bit(argv[arg++]);
+			// parse page options and then override the header/footer settings
+			for (;arg < argc;++arg) {
+				if (argv[arg][0] != '-' || argv[arg][1] == '\0' || defaultMode) break;
+				parseArg(sections, argc, argv, defaultMode, arg, (char*)&ps);
+			}
 
 			ps.header.left = ps.header.right = ps.header.center = "";
 			ps.footer.left = ps.footer.right = ps.footer.center = "";
 			ps.header.line = ps.footer.line = false;
 			ps.header.htmlUrl = ps.footer.htmlUrl = "";
 			ps.includeInOutline = false;
 
-			//Setup various cover settings here
-			++arg;
+			continue;
 		} else if (!strcmp(argv[arg],"toc")) {
 			++arg;
 			sections = page | toc;