summaryrefslogtreecommitdiffstats
path: root/lib/dup.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--lib/dup.c92
1 files changed, 92 insertions, 0 deletions
diff --git a/lib/dup.c b/lib/dup.c
new file mode 100644
index 0000000..17a9c58
--- /dev/null
+++ b/lib/dup.c
@@ -0,0 +1,92 @@
+/* Duplicate an open file descriptor.
+
+ Copyright (C) 2011-2022 Free Software Foundation, Inc.
+
+ This file is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Lesser General Public License as
+ published by the Free Software Foundation; either version 2.1 of the
+ License, or (at your option) any later version.
+
+ This file is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+#include <config.h>
+
+/* Specification. */
+#include <unistd.h>
+
+#include <errno.h>
+
+#if HAVE_MSVC_INVALID_PARAMETER_HANDLER
+# include "msvc-inval.h"
+#endif
+
+#undef dup
+
+#if defined _WIN32 && !defined __CYGWIN__
+# if HAVE_MSVC_INVALID_PARAMETER_HANDLER
+static int
+dup_nothrow (int fd)
+{
+ int result;
+
+ TRY_MSVC_INVAL
+ {
+ result = _dup (fd);
+ }
+ CATCH_MSVC_INVAL
+ {
+ result = -1;
+ errno = EBADF;
+ }
+ DONE_MSVC_INVAL;
+
+ return result;
+}
+# else
+# define dup_nothrow _dup
+# endif
+#elif defined __KLIBC__
+# include <fcntl.h>
+# include <sys/stat.h>
+
+# include <InnoTekLIBC/backend.h>
+
+static int
+dup_nothrow (int fd)
+{
+ int dupfd;
+ struct stat sbuf;
+
+ dupfd = dup (fd);
+ if (dupfd == -1 && errno == ENOTSUP \
+ && !fstat (fd, &sbuf) && S_ISDIR (sbuf.st_mode))
+ {
+ char path[_MAX_PATH];
+
+ /* Get a path from fd */
+ if (!__libc_Back_ioFHToPath (fd, path, sizeof (path)))
+ dupfd = open (path, O_RDONLY);
+ }
+
+ return dupfd;
+}
+#else
+# define dup_nothrow dup
+#endif
+
+int
+rpl_dup (int fd)
+{
+ int result = dup_nothrow (fd);
+#if REPLACE_FCHDIR
+ if (result >= 0)
+ result = _gl_register_dup (fd, result);
+#endif
+ return result;
+}