Set correct path to (biblatex) bibliography databases that are entered relative to child documents.

Fixes: #11105
(cherry picked from commit 2ecc3b09c6)

src/Buffer.cpp

@@ -3185,9 +3185,27 @@ vector<docstring> const Buffer::prepareBibFilePaths(OutputParams const & runpara
 		string utf8input = to_utf8(it->first);
 		string database =
 			prepareFileNameForLaTeX(utf8input, ".bib", runparams.nice);
-		FileName const try_in_file =
+		FileName try_in_file =
 			makeAbsPath(database + ".bib", filePath());
-		bool const not_from_texmf = try_in_file.isReadableFile();
+		bool not_from_texmf = try_in_file.isReadableFile();
+		// If the file has not been found, try with the real file name
+		// (it might come from a child in a sub-directory)
+		if (!not_from_texmf) {
+			try_in_file = it->second;
+			if (try_in_file.isReadableFile()) {
+				// Check if the file is in texmf
+				FileName kpsefile(findtexfile(changeExtension(utf8input, "bib"), "bib", true));
+				not_from_texmf = kpsefile.empty()
+						|| kpsefile.absFileName() != try_in_file.absFileName();
+				if (not_from_texmf)
+					// If this exists, make path relative to the master
+					// FIXME Unicode
+					database = removeExtension(
+							prepareFileNameForLaTeX(to_utf8(makeRelPath(from_utf8(try_in_file.absFileName()),
+												    from_utf8(filePath()))),
+										".bib", runparams.nice));
+			}
+		}
 
 		if (!runparams.inComment && !runparams.dryrun && !runparams.nice &&
 		    not_from_texmf) {

src/support/filetools.cpp

@@ -1094,7 +1094,8 @@ cmd_ret const runCommand(string const & cmd)
 }
 
 
-FileName const findtexfile(string const & fil, string const & /*format*/)
+FileName const findtexfile(string const & fil, string const & /*format*/,
+						   bool const onlykpse)
 {
 	/* There is no problem to extend this function too use other
 	   methods to look for files. It could be setup to look
@@ -1107,9 +1108,11 @@ FileName const findtexfile(string const & fil, string const & /*format*/)
 
 	// If the file can be found directly, we just return a
 	// absolute path version of it.
+	if (!onlykpse) {
 		FileName const absfile(makeAbsPath(fil));
 		if (absfile.exists())
 			return absfile;
+	}
 
 	// Now we try to find it using kpsewhich.
 	// It seems from the kpsewhich manual page that it is safe to use

src/support/filetools.h

@@ -282,7 +282,8 @@ bool readLink(FileName const & file, FileName & link);
  * \param format The file format as used by kpsewhich, e.g. "bib", "bst" etc.
  */
 FileName const findtexfile(std::string const & fil,
-			      std::string const & format);
+						   std::string const & format,
+						   bool const onlykpse = false);
 
 /** \param file1, file2 the two files to be compared. Must have absolute paths.
  *  \returns 1 if \c file1 has a more recent timestamp than \c file2,

status.23x

@@ -94,7 +94,7 @@ What's new
 
 * DOCUMENT INPUT/OUTPUT
 
-- Fix language settings annd line spacing in InPreamble-titles
+- Fix language settings and line spacing in InPreamble-titles
   (bug 9332, 1049).
 
 - Respect 'literal' setting when calculating longest bibitem (bug 10817).
@@ -104,6 +104,9 @@ What's new
 
 - Fix polyglossia language switches for Arabic (bug 11057).
 
+- Set correct path to (biblatex) bibliography databases that are entered
+  relative to child documents (bug 11105).
+
 
 * LYX2LYX