+#ifndef _WIN32
+/*
+ * Dups an fd and sets the flags
+ */
+static int qemu_dup_flags(int fd, int flags)
+{
+ int ret;
+ int serrno;
+ int dup_flags;
+ int setfl_flags;
+
+#ifdef F_DUPFD_CLOEXEC
+ ret = fcntl(fd, F_DUPFD_CLOEXEC, 0);
+#else
+ ret = dup(fd);
+ if (ret != -1) {
+ qemu_set_cloexec(ret);
+ }
+#endif
+ if (ret == -1) {
+ goto fail;
+ }
+
+ dup_flags = fcntl(ret, F_GETFL);
+ if (dup_flags == -1) {
+ goto fail;
+ }
+
+ if ((flags & O_SYNC) != (dup_flags & O_SYNC)) {
+ errno = EINVAL;
+ goto fail;
+ }
+
+ /* Set/unset flags that we can with fcntl */
+ setfl_flags = O_APPEND | O_ASYNC | O_DIRECT | O_NOATIME | O_NONBLOCK;
+ dup_flags &= ~setfl_flags;
+ dup_flags |= (flags & setfl_flags);
+ if (fcntl(ret, F_SETFL, dup_flags) == -1) {
+ goto fail;
+ }
+
+ /* Truncate the file in the cases that open() would truncate it */
+ if (flags & O_TRUNC ||
+ ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))) {
+ if (ftruncate(ret, 0) == -1) {
+ goto fail;
+ }
+ }
+
+ return ret;
+
+fail:
+ serrno = errno;
+ if (ret != -1) {
+ close(ret);
+ }
+ errno = serrno;
+ return -1;
+}
+#endif