1 files changed, 24 insertions, 17 deletions

diff --git a/src/doc.c b/src/doc.c
index 1d3d1e64442..1ddaa117bba 100644
--- a/src/doc.c
+++ b/src/doc.c
@@ -1,6 +1,7 @@
 /* Record indices of function doc strings stored in a file.
 
-Copyright (C) 1985-1986, 1993-1995, 1997-2012 Free Software Foundation, Inc.
+Copyright (C) 1985-1986, 1993-1995, 1997-2013 Free Software Foundation,
+Inc.
 
 This file is part of GNU Emacs.
 
@@ -83,24 +84,23 @@ get_doc_string (Lisp_Object filepos, bool unibyte, bool definition)
   ptrdiff_t minsize;
   int offset;
   EMACS_INT position;
-  Lisp_Object file, tem;
+  Lisp_Object file, tem, pos;
   USE_SAFE_ALLOCA;
 
   if (INTEGERP (filepos))
     {
       file = Vdoc_file_name;
-      position = XINT (filepos);
+      pos = filepos;
     }
   else if (CONSP (filepos))
     {
       file = XCAR (filepos);
-      position = XINT (XCDR (filepos));
+      pos = XCDR (filepos);
     }
   else
     return Qnil;
 
-  if (position < 0)
-    position = - position;
+  position = eabs (XINT (pos));
 
   if (!STRINGP (Vdoc_directory))
     return Qnil;
@@ -176,9 +176,9 @@ get_doc_string (Lisp_Object filepos, bool unibyte, bool definition)
       if (space_left <= 0)
         {
           ptrdiff_t in_buffer = p - get_doc_string_buffer;
-          get_doc_string_buffer =
-            xpalloc (get_doc_string_buffer, &get_doc_string_buffer_size,
-                     16 * 1024, -1, 1);
+          get_doc_string_buffer
+            = xpalloc (get_doc_string_buffer, &get_doc_string_buffer_size,
+                       16 * 1024, -1, 1);
           p = get_doc_string_buffer + in_buffer;
           space_left = (get_doc_string_buffer_size - 1
                         - (p - get_doc_string_buffer));
@@ -279,10 +279,10 @@ Invalid data in documentation file -- %c followed by code %03o",
   else
     {
       /* The data determines whether the string is multibyte.  */
-      ptrdiff_t nchars =
-        multibyte_chars_in_text (((unsigned char *) get_doc_string_buffer
-                                  + offset),
-                                 to - (get_doc_string_buffer + offset));
+      ptrdiff_t nchars
+        = multibyte_chars_in_text (((unsigned char *) get_doc_string_buffer
+                                    + offset),
+                                   to - (get_doc_string_buffer + offset));
       return make_string_from_bytes (get_doc_string_buffer + offset,
                                      nchars,
                                      to - (get_doc_string_buffer + offset));
@@ -338,6 +338,14 @@ string is passed through `substitute-command-keys'.  */)
 
   doc = Qnil;
 
+  if (SYMBOLP (function))
+    {
+      Lisp_Object tem = Fget (function, Qfunction_documentation);
+      if (!NILP (tem))
+        return Fdocumentation_property (function, Qfunction_documentation,
+                                        raw);
+    }
+
   fun = Findirect_function (function, Qnil);
   if (CONSP (fun) && EQ (XCAR (fun), Qmacro))
     fun = XCDR (fun);
@@ -622,11 +630,10 @@ the same file name is found in the `doc-directory'.  */)
         break;
 
       buf[filled] = 0;
-      p = buf;
       end = buf + (filled < 512 ? filled : filled - 128);
-      while (p != end && *p != '\037') p++;
+      p = memchr (buf, '\037', end - buf);
       /* p points to ^_Ffunctionname\n or ^_Vvarname\n or ^_Sfilename\n.  */
-      if (p != end)
+      if (p)
         {
           end = strchr (p, '\n');
 
@@ -819,7 +826,7 @@ Otherwise, return a new string, without any text properties.  */)
           if (NILP (tem))       /* but not on any keys */
             {
               ptrdiff_t offset = bufp - buf;
-              if (STRING_BYTES_BOUND - 4 < bsize)
+              if (bsize > STRING_BYTES_BOUND - 4)
                 string_overflow ();
               buf = xrealloc (buf, bsize += 4);
               bufp = buf + offset;