diff --git a/doc/config.rst b/doc/config.rst
index a19ca5d29..a71555974 100644
--- a/doc/config.rst
+++ b/doc/config.rst
@@ -870,6 +870,13 @@ that use Sphinx's HTMLWriter class.
 
    .. versionadded:: 0.6
 
+.. confval:: html_sourcelink_suffix
+
+   Suffix to be appended to source links (see :confval:`html_show_sourcelink`),
+   unless they have this suffix already.  Default is ``'.txt'``.
+
+   .. versionadded:: 1.5
+
 .. confval:: html_use_opensearch
 
    If nonempty, an `OpenSearch <http://www.opensearch.org/Home>`_ description file will be
diff --git a/sphinx/builders/html.py b/sphinx/builders/html.py
index 63ccdd66c..09fe96be0 100644
--- a/sphinx/builders/html.py
+++ b/sphinx/builders/html.py
@@ -339,6 +339,7 @@ class StandaloneHTMLBuilder(Builder):
             show_sphinx = self.config.html_show_sphinx,
             has_source = self.config.html_copy_source,
             show_source = self.config.html_show_sourcelink,
+            sourcelink_suffix = self.config.html_sourcelink_suffix,
             file_suffix = self.out_suffix,
             script_files = self.script_files,
             language = self.config.language,
@@ -402,15 +403,21 @@ class StandaloneHTMLBuilder(Builder):
         # title rendered as HTML
         title = self.env.longtitles.get(docname)
         title = title and self.render_partial(title)['title'] or ''
+
+        # Suffix for the document
+        source_suffix = path.splitext(self.env.doc2path(docname))[1]
+
         # the name for the copied source
-        sourcename = self.config.html_copy_source and docname + '.txt' or ''
+        if self.config.html_copy_source:
+            sourcename = docname + source_suffix
+            if source_suffix != self.config.html_sourcelink_suffix:
+                sourcename += self.config.html_sourcelink_suffix
+        else:
+            sourcename = ''
 
         # metadata for the document
         meta = self.env.metadata.get(docname)
 
-        # Suffix for the document
-        source_suffix = '.' + self.env.doc2path(docname).split('.')[-1]
-
         # local TOC and global TOC tree
         self_toc = self.env.get_toc_for(docname, self)
         toc = self.render_partial(self_toc)['fragment']
@@ -712,7 +719,12 @@ class StandaloneHTMLBuilder(Builder):
     def index_page(self, pagename, doctree, title):
         # only index pages with title
         if self.indexer is not None and title:
-            self.indexer.feed(pagename, title, doctree)
+            filename = self.env.doc2path(pagename, base=None)
+            try:
+                self.indexer.feed(pagename, filename, title, doctree)
+            except TypeError:
+                # fallback for old search-adapters
+                self.indexer.feed(pagename, title, doctree)
 
     def _get_local_toctree(self, docname, collapse=True, **kwds):
         if 'includehidden' not in kwds:
diff --git a/sphinx/config.py b/sphinx/config.py
index 80616ca64..0954efeb2 100644
--- a/sphinx/config.py
+++ b/sphinx/config.py
@@ -121,6 +121,7 @@ class Config(object):
         html_split_index = (False, 'html'),
         html_copy_source = (True, 'html'),
         html_show_sourcelink = (True, 'html'),
+        html_sourcelink_suffix = ('.txt', 'html'),
         html_use_opensearch = ('', 'html'),
         html_file_suffix = (None, 'html', string_classes),
         html_link_suffix = (None, 'html', string_classes),
diff --git a/sphinx/search/__init__.py b/sphinx/search/__init__.py
index 8bbce360e..704532eb2 100644
--- a/sphinx/search/__init__.py
+++ b/sphinx/search/__init__.py
@@ -226,11 +226,13 @@ class IndexBuilder(object):
 
     def __init__(self, env, lang, options, scoring):
         self.env = env
-        # filename -> title
+        # docname -> title
         self._titles = {}
-        # stemmed word -> set(filenames)
+        # docname -> filename
+        self._filenames = {}
+        # stemmed word -> set(docname)
         self._mapping = {}
-        # stemmed words in titles -> set(filenames)
+        # stemmed words in titles -> set(docname)
         self._title_mapping = {}
         # word -> stemmed word
         self._stem_cache = {}
@@ -338,15 +340,16 @@ class IndexBuilder(object):
 
     def freeze(self):
         """Create a usable data structure for serializing."""
-        filenames, titles = zip(*sorted(self._titles.items()))
-        fn2index = dict((f, i) for (i, f) in enumerate(filenames))
+        docnames, titles = zip(*sorted(self._titles.items()))
+        filenames = [self._filenames.get(docname) for docname in docnames]
+        fn2index = dict((f, i) for (i, f) in enumerate(docnames))
         terms, title_terms = self.get_terms(fn2index)
 
         objects = self.get_objects(fn2index)  # populates _objtypes
         objtypes = dict((v, k[0] + ':' + k[1])
                         for (k, v) in iteritems(self._objtypes))
         objnames = self._objnames
-        return dict(filenames=filenames, titles=titles, terms=terms,
+        return dict(docnames=docnames, filenames=filenames, titles=titles, terms=terms,
                     objects=objects, objtypes=objtypes, objnames=objnames,
                     titleterms=title_terms, envversion=self.env.version)
 
@@ -365,9 +368,11 @@ class IndexBuilder(object):
         for wordnames in itervalues(self._title_mapping):
             wordnames.intersection_update(filenames)
 
-    def feed(self, filename, title, doctree):
+    def feed(self, docname, filename, title, doctree):
         """Feed a doctree to the index."""
-        self._titles[filename] = title
+        self._titles[docname] = title
+        self._filenames[docname] = filename
+
         visitor = WordCollector(doctree, self.lang)
         doctree.walk(visitor)
 
@@ -383,12 +388,12 @@ class IndexBuilder(object):
         for word in visitor.found_title_words:
             word = stem(word)
             if _filter(word):
-                self._title_mapping.setdefault(word, set()).add(filename)
+                self._title_mapping.setdefault(word, set()).add(docname)
 
         for word in visitor.found_words:
             word = stem(word)
             if word not in self._title_mapping and _filter(word):
-                self._mapping.setdefault(word, set()).add(filename)
+                self._mapping.setdefault(word, set()).add(docname)
 
     def context_for_searchtool(self):
         return dict(
diff --git a/sphinx/themes/basic/layout.html b/sphinx/themes/basic/layout.html
index 1afc4a0bf..f8ff477c7 100644
--- a/sphinx/themes/basic/layout.html
+++ b/sphinx/themes/basic/layout.html
@@ -91,7 +91,8 @@
         VERSION:     '{{ release|e }}',
         COLLAPSE_INDEX: false,
         FILE_SUFFIX: '{{ '' if no_search_suffix else file_suffix }}',
-        HAS_SOURCE:  {{ has_source|lower }}
+        HAS_SOURCE:  {{ has_source|lower }},
+        SOURCELINK_SUFFIX: '{{ sourcelink_suffix }}'
       };
     </script>
     {%- for scriptfile in script_files %}
diff --git a/sphinx/themes/basic/static/searchtools.js_t b/sphinx/themes/basic/static/searchtools.js_t
index 8a150b272..9d70f4303 100644
--- a/sphinx/themes/basic/static/searchtools.js_t
+++ b/sphinx/themes/basic/static/searchtools.js_t
@@ -256,7 +256,8 @@ var Search = {
             displayNextItem();
           });
         } else if (DOCUMENTATION_OPTIONS.HAS_SOURCE) {
-          $.ajax({url: DOCUMENTATION_OPTIONS.URL_ROOT + '_sources/' + item[0] + '.txt',
+          var suffix = DOCUMENTATION_OPTIONS.SOURCELINK_SUFFIX;
+          $.ajax({url: DOCUMENTATION_OPTIONS.URL_ROOT + '_sources/' + item[5] + (item[5].endsWith(suffix) ? '' : suffix),
                   dataType: "text",
                   complete: function(jqxhr, textstatus) {
                     var data = jqxhr.responseText;
@@ -295,6 +296,7 @@ var Search = {
    */
   performObjectSearch : function(object, otherterms) {
     var filenames = this._index.filenames;
+    var docnames = this._index.docnames;
     var objects = this._index.objects;
     var objnames = this._index.objnames;
     var titles = this._index.titles;
@@ -348,7 +350,7 @@ var Search = {
           } else {
             score += Scorer.objPrioDefault;
           }
-          results.push([filenames[match[0]], fullname, '#'+anchor, descr, score]);
+          results.push([docnames[match[0]], fullname, '#'+anchor, descr, score, filenames[match[0]]]);
         }
       }
     }
@@ -360,6 +362,7 @@ var Search = {
    * search for full-text terms in the index
    */
   performTermsSearch : function(searchterms, excluded, terms, titleterms) {
+    var docnames = this._index.docnames;
     var filenames = this._index.filenames;
     var titles = this._index.titles;
 
@@ -434,7 +437,7 @@ var Search = {
         // select one (max) score for the file.
         // for better ranking, we should calculate ranking by using words statistics like basic tf-idf...
         var score = $u.max($u.map(fileMap[file], function(w){return scoreMap[file][w]}));
-        results.push([filenames[file], titles[file], '', null, score]);
+        results.push([docnames[file], titles[file], '', null, score, filenames[file]]);
       }
     }
     return results;
diff --git a/sphinx/websupport/search/__init__.py b/sphinx/websupport/search/__init__.py
index 844a3b468..80b5a3535 100644
--- a/sphinx/websupport/search/__init__.py
+++ b/sphinx/websupport/search/__init__.py
@@ -34,19 +34,20 @@ class BaseSearch(object):
         """
         pass
 
-    def feed(self, pagename, title, doctree):
+    def feed(self, pagename, filename, title, doctree):
         """Called by the builder to add a doctree to the index. Converts the
         `doctree` to text and passes it to :meth:`add_document`. You probably
         won't want to override this unless you need access to the `doctree`.
         Override :meth:`add_document` instead.
 
         :param pagename: the name of the page to be indexed
+        :param filename: the name of the original source file
         :param title: the title of the page to be indexed
         :param doctree: is the docutils doctree representation of the page
         """
-        self.add_document(pagename, title, doctree.astext())
+        self.add_document(pagename, filename, title, doctree.astext())
 
-    def add_document(self, pagename, title, text):
+    def add_document(self, pagename, filename, title, text):
         """Called by :meth:`feed` to add a document to the search index.
         This method should should do everything necessary to add a single
         document to the search index.
@@ -59,6 +60,7 @@ class BaseSearch(object):
         query.
 
         :param pagename: the name of the page being indexed
+        :param filename: the name of the original source file
         :param title: the page's title
         :param text: the full text of the page
         """
diff --git a/sphinx/websupport/search/nullsearch.py b/sphinx/websupport/search/nullsearch.py
index 9e990b1cf..4d0db9553 100644
--- a/sphinx/websupport/search/nullsearch.py
+++ b/sphinx/websupport/search/nullsearch.py
@@ -17,7 +17,7 @@ class NullSearch(BaseSearch):
     """A search adapter that does nothing. Used when no search adapter
     is specified.
     """
-    def feed(self, pagename, title, doctree):
+    def feed(self, pagename, filename, title, doctree):
         pass
 
     def query(self, q):
diff --git a/sphinx/websupport/search/whooshsearch.py b/sphinx/websupport/search/whooshsearch.py
index 4b0769f50..f31dc4d52 100644
--- a/sphinx/websupport/search/whooshsearch.py
+++ b/sphinx/websupport/search/whooshsearch.py
@@ -44,7 +44,7 @@ class WhooshSearch(BaseSearch):
     def finish_indexing(self):
         self.index_writer.commit()
 
-    def add_document(self, pagename, title, text):
+    def add_document(self, pagename, filename, title, text):
         self.index_writer.add_document(path=text_type(pagename),
                                        title=title,
                                        text=text)
diff --git a/tests/test_build_html.py b/tests/test_build_html.py
index f45b56066..173ad6cf5 100644
--- a/tests/test_build_html.py
+++ b/tests/test_build_html.py
@@ -68,6 +68,7 @@ HTML_XPATH = {
         (".//img[@src='_images/img1.png']", ''),
         (".//img[@src='_images/simg.png']", ''),
         (".//img[@src='_images/svgimg.svg']", ''),
+        (".//a[@href='_sources/images.txt']", ''),
     ],
     'subdir/images.html': [
         (".//img[@src='../_images/img1.png']", ''),
@@ -318,6 +319,7 @@ HTML_XPATH = {
     ],
     'otherext.html': [
         (".//h1", "Generated section"),
+        (".//a[@href='_sources/otherext.foo.txt']", ''),
     ]
 }
 
@@ -985,3 +987,15 @@ def test_html_extra_path(app, status, warning):
     assert (app.outdir / 'rimg.png').exists()
     assert not (app.outdir / '_build/index.html').exists()
     assert (app.outdir / 'background.png').exists()
+
+
+@with_app(buildername='html', confoverrides={'html_sourcelink_suffix': ''})
+def test_html_sourcelink_suffix(app, status, warning):
+    app.builder.build_all()
+    content_otherext = (app.outdir / 'otherext.html').text()
+    content_images = (app.outdir / 'images.html').text()
+
+    assert '<a href="_sources/otherext.foo"' in content_otherext
+    assert '<a href="_sources/images.txt"' in content_images
+    assert (app.outdir / '_sources' / 'otherext.foo').exists()
+    assert (app.outdir / '_sources' / 'images.txt').exists()
diff --git a/tests/test_search.py b/tests/test_search.py
index 23d6b933a..a8af7247f 100644
--- a/tests/test_search.py
+++ b/tests/test_search.py
@@ -53,7 +53,7 @@ def test_wordcollector():
     parser.parse(FILE_CONTENTS, doc)
 
     ix = IndexBuilder(None, 'en', {}, None)
-    ix.feed('filename', 'title', doc)
+    ix.feed('docname', 'filename', 'title', doc)
     assert 'boson' not in ix._mapping
     assert 'fermion' in ix._mapping
 
diff --git a/tests/test_searchadapters.py b/tests/test_searchadapters.py
index f6a389fea..e8c5c9364 100644
--- a/tests/test_searchadapters.py
+++ b/tests/test_searchadapters.py
@@ -41,7 +41,7 @@ def search_adapter_helper(adapter):
 
     # Make sure documents are properly updated by the search adapter.
     s.init_indexing(changed=['markup'])
-    s.add_document(u'markup', u'title', u'SomeLongRandomWord')
+    s.add_document(u'markup', u'filename', u'title', u'SomeLongRandomWord')
     s.finish_indexing()
     # Now a search for "Epigraph" should return zero results.
     results = s.query(u'Epigraph')