5 files changed, 50 insertions, 10 deletions
diff --git a/src/common/compat.c b/src/common/compat.c
index 11e2545709..6d36321193 100644
--- a/src/common/compat.c
+++ b/src/common/compat.c
@@ -823,6 +823,7 @@ replace_file(const char *from, const char *to)
     case FN_NOENT:
       break;
     case FN_FILE:
+    case FN_EMPTY:
       if (unlink(to)) return -1;
       break;
     case FN_ERROR:
diff --git a/src/common/compat_libevent.h b/src/common/compat_libevent.h
index 69259e7ed6..6bbfae0056 100644
--- a/src/common/compat_libevent.h
+++ b/src/common/compat_libevent.h
@@ -5,6 +5,7 @@
 #define TOR_COMPAT_LIBEVENT_H
 
 #include "orconfig.h"
+#include "testsupport.h"
 
 struct event;
 struct event_base;
diff --git a/src/common/tortls.c b/src/common/tortls.c
index dd33b330dc..ca629135a6 100644
--- a/src/common/tortls.c
+++ b/src/common/tortls.c
@@ -29,6 +29,20 @@
     #include <ws2tcpip.h>
  #endif
 #endif
+
+#ifdef __GNUC__
+#define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
+#endif
+
+#if __GNUC__ && GCC_VERSION >= 402
+#if GCC_VERSION >= 406
+#pragma GCC diagnostic push
+#endif
+/* Some versions of OpenSSL declare SSL_get_selected_srtp_profile twice in
+ * srtp.h. Suppress the GCC warning so we can build with -Wredundant-decl. */
+#pragma GCC diagnostic ignored "-Wredundant-decls"
+#endif
+
 #include <openssl/ssl.h>
 #include <openssl/ssl3.h>
 #include <openssl/err.h>
@@ -37,6 +51,14 @@
 #include <openssl/bio.h>
 #include <openssl/opensslv.h>
 
+#if __GNUC__ && GCC_VERSION >= 402
+#if GCC_VERSION >= 406
+#pragma GCC diagnostic pop
+#else
+#pragma GCC diagnostic warning "-Wredundant-decls"
+#endif
+#endif
+
 #ifdef USE_BUFFEREVENTS
 #include <event2/bufferevent_ssl.h>
 #include <event2/buffer.h>
diff --git a/src/common/util.c b/src/common/util.c
index e5dec99707..f7baab0791 100644
--- a/src/common/util.c
+++ b/src/common/util.c
@@ -2018,15 +2018,24 @@ clean_name_for_stat(char *name)
 #endif
 }
 
-/** Return FN_ERROR if filename can't be read, FN_NOENT if it doesn't
- * exist, FN_FILE if it is a regular file, or FN_DIR if it's a
- * directory.  On FN_ERROR, sets errno. */
+/** Return:
+ * FN_ERROR if filename can't be read, is NULL, or is zero-length,
+ * FN_NOENT if it doesn't exist,
+ * FN_FILE if it is a non-empty regular file, or a FIFO on unix-like systems,
+ * FN_EMPTY for zero-byte regular files,
+ * FN_DIR if it's a directory, and
+ * FN_ERROR for any other file type.
+ * On FN_ERROR and FN_NOENT, sets errno.  (errno is not set when FN_ERROR
+ * is returned due to an unhandled file type.) */
 file_status_t
 file_status(const char *fname)
 {
   struct stat st;
   char *f;
   int r;
+  if (!fname || strlen(fname) == 0) {
+    return FN_ERROR;
+  }
   f = tor_strdup(fname);
   clean_name_for_stat(f);
   log_debug(LD_FS, "stat()ing %s", f);
@@ -2038,16 +2047,23 @@ file_status(const char *fname)
     }
     return FN_ERROR;
   }
-  if (st.st_mode & S_IFDIR)
+  if (st.st_mode & S_IFDIR) {
     return FN_DIR;
-  else if (st.st_mode & S_IFREG)
-    return FN_FILE;
+  } else if (st.st_mode & S_IFREG) {
+    if (st.st_size > 0) {
+      return FN_FILE;
+    } else if (st.st_size == 0) {
+      return FN_EMPTY;
+    } else {
+      return FN_ERROR;
+    }
 #ifndef _WIN32
-  else if (st.st_mode & S_IFIFO)
+  } else if (st.st_mode & S_IFIFO) {
     return FN_FILE;
 #endif
-  else
+  } else {
     return FN_ERROR;
+  }
 }
 
 /** Check whether <b>dirname</b> exists and is private.  If yes return 0.  If
@@ -2966,7 +2982,7 @@ expand_filename(const char *filename)
       tor_free(username);
       rest = slash ? (slash+1) : "";
 #else
-      log_warn(LD_CONFIG, "Couldn't expend homedir on system without pwd.h");
+      log_warn(LD_CONFIG, "Couldn't expand homedir on system without pwd.h");
       return tor_strdup(filename);
 #endif
     }
diff --git a/src/common/util.h b/src/common/util.h
index ee40949b61..1b8fc74db5 100644
--- a/src/common/util.h
+++ b/src/common/util.h
@@ -342,7 +342,7 @@ enum stream_status get_string_from_pipe(FILE *stream, char *buf, size_t count);
 
 /** Return values from file_status(); see that function's documentation
  * for details. */
-typedef enum { FN_ERROR, FN_NOENT, FN_FILE, FN_DIR } file_status_t;
+typedef enum { FN_ERROR, FN_NOENT, FN_FILE, FN_DIR, FN_EMPTY } file_status_t;
 file_status_t file_status(const char *filename);
 
 /** Possible behaviors for check_private_dir() on encountering a nonexistent