From 9bc236c8263bc81f1b540579a9f98d872ab2da46 Mon Sep 17 00:00:00 2001
From: Tassilo Horn <tsdh@gnu.org>
Date: Fri, 1 Nov 2013 11:27:21 +0100
Subject: [PATCH] Allow multiple bibliographies when BibLaTeX is used rathen
 than BibTeX. * textmodes/reftex-parse.el (reftex-using-biblatex-p): New
 function. (reftex-locate-bibliography-files): Us it.

---
 lisp/ChangeLog                 |  7 +++++++
 lisp/textmodes/reftex-parse.el | 38 +++++++++++++++++++++++++---------
 2 files changed, 35 insertions(+), 10 deletions(-)

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index fd8e77c9c53..1493945af38 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,10 @@
+2013-11-01  Tassilo Horn  <tsdh@gnu.org>
+
+	Allow multiple bibliographies when BibLaTeX is used rathen than
+	BibTeX.
+	* textmodes/reftex-parse.el (reftex-using-biblatex-p): New function.
+	(reftex-locate-bibliography-files): Us it.
+
 2013-11-01  Claudio Bley  <claudio.bley@googlemail.com>
 
 	* image.el (image-type-header-regexps): Fix the 'pbm' part to
diff --git a/lisp/textmodes/reftex-parse.el b/lisp/textmodes/reftex-parse.el
index a99791e5427..ffabb134c83 100644
--- a/lisp/textmodes/reftex-parse.el
+++ b/lisp/textmodes/reftex-parse.el
@@ -350,20 +350,38 @@ of master file."
     ;; Return the list
     docstruct))
 
+(defun reftex-using-biblatex-p ()
+  "Return non-nil iff we are using biblatex rather than bibtex."
+  (if (boundp 'TeX-active-styles)
+      ;; the sophisticated AUCTeX way
+      (member "biblatex" TeX-active-styles)
+    ;; poor-man's check...
+    (save-excursion
+      (re-search-forward "^[^%]*\\\\usepackage.*{biblatex}" nil t))))
+
 (defun reftex-locate-bibliography-files (master-dir &optional files)
-  "Scan buffer for bibliography macro and return file list."
+  "Scan buffer for bibliography macros and return file list."
   (unless files
     (save-excursion
       (goto-char (point-min))
-      (if (re-search-forward
-           (concat
-;           "\\(\\`\\|[\n\r]\\)[^%]*\\\\\\("
-            "\\(^\\)[^%\n\r]*\\\\\\("
-            (mapconcat 'identity reftex-bibliography-commands "\\|")
-            "\\)\\(\\[.+?\\]\\)?{[ \t]*\\([^}]+\\)") nil t)
-          (setq files
-                (split-string (reftex-match-string 4)
-                              "[ \t\n\r]*,[ \t\n\r]*")))))
+      ;; when biblatex is used, multiple \bibliography or
+      ;; \addbibresource macros are allowed.  With plain bibtex, only
+      ;; the first is used.
+      (let ((using-biblatex (reftex-using-biblatex-p))
+	    (again t))
+	(while (and again
+		    (re-search-forward
+		     (concat
+		      ;;           "\\(\\`\\|[\n\r]\\)[^%]*\\\\\\("
+		      "\\(^\\)[^%\n\r]*\\\\\\("
+		      (mapconcat 'identity reftex-bibliography-commands "\\|")
+		      "\\)\\(\\[.+?\\]\\)?{[ \t]*\\([^}]+\\)") nil t))
+	  (setq files
+		(append files
+			(split-string (reftex-match-string 4)
+				      "[ \t\n\r]*,[ \t\n\r]*")))
+	  (unless using-biblatex
+	    (setq again nil))))))
   (when files
     (setq files
           (mapcar
-- 
2.39.2