rename: a new file for Curl_rename()

And make the cookie save function use it.

1 files changed, 62 insertions, 0 deletions

diff --git a/lib/rename.c b/lib/rename.c
new file mode 100644
index 000000000..bb170d3cc
--- /dev/null
+++ b/lib/rename.c
@@ -0,0 +1,62 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 2020, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at https://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ***************************************************************************/
+
+#include "rename.h"
+
+#include "curl_setup.h"
+
+#if (!defined(CURL_DISABLE_HTTP) && !defined(CURL_DISABLE_COOKIES)) ||  \
+  defined(USE_ALTSVC)
+
+#include "timeval.h"
+
+/* The last 3 #include files should be in this order */
+#include "curl_printf.h"
+#include "curl_memory.h"
+#include "memdebug.h"
+
+/* return 0 on success, 1 on error */
+int Curl_rename(const char *oldpath, const char *newpath)
+{
+#ifdef WIN32
+  /* rename() on Windows doesn't overwrite, so we can't use it here.
+     MoveFileExA() will overwrite and is usually atomic, however it fails
+     when there are open handles to the file. */
+  const int max_wait_ms = 1000;
+  struct curltime start = Curl_now();
+  for(;;) {
+    timediff_t diff;
+    if(MoveFileExA(oldpath, newpath, MOVEFILE_REPLACE_EXISTING))
+      break;
+    diff = Curl_timediff(Curl_now(), start);
+    if(diff < 0 || diff > max_wait_ms)
+      return 1;
+    Sleep(1);
+  }
+#else
+  if(rename(oldpath, newpath))
+    return 1;
+#endif
+  return 0;
+}
+
+#endif