Move fix_fname from buffer.c

src/path.c

@@ -1620,3 +1620,45 @@ vim_FullName (
   return retval;
 }
 
+/*
+ * If fname is not a full path, make it a full path.
+ * Returns pointer to allocated memory (NULL for failure).
+ */
+char_u *fix_fname(char_u *fname)
+{
+  /*
+   * Force expanding the path always for Unix, because symbolic links may
+   * mess up the full path name, even though it starts with a '/'.
+   * Also expand when there is ".." in the file name, try to remove it,
+   * because "c:/src/../README" is equal to "c:/README".
+   * Similarly "c:/src//file" is equal to "c:/src/file".
+   * For MS-Windows also expand names like "longna~1" to "longname".
+   */
+#ifdef UNIX
+  return FullName_save(fname, TRUE);
+#else
+  if (!vim_isAbsName(fname)
+      || strstr((char *)fname, "..") != NULL
+      || strstr((char *)fname, "//") != NULL
+# ifdef BACKSLASH_IN_FILENAME
+      || strstr((char *)fname, "\\\\") != NULL
+# endif
+      )
+    return FullName_save(fname, FALSE);
+
+  fname = vim_strsave(fname);
+
+# ifdef USE_FNAME_CASE
+#  ifdef USE_LONG_FNAME
+  if (USE_LONG_FNAME)
+#  endif
+  {
+    if (fname != NULL)
+      fname_case(fname, 0);             /* set correct case for file name */
+  }
+# endif
+
+  return fname;
+#endif
+}
+