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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 17:39:29 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 17:39:29 +0000
commit8ffec2a3aba6f114784e11f89ef1d57a096ae540 (patch)
treeccebcbad06203e8241a8e7249f8e6c478a3682ea /lib/fclose.c
parentInitial commit. (diff)
downloadcoreutils-8ffec2a3aba6f114784e11f89ef1d57a096ae540.tar.xz
coreutils-8ffec2a3aba6f114784e11f89ef1d57a096ae540.zip
Adding upstream version 8.32.upstream/8.32upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/fclose.c')
-rw-r--r--lib/fclose.c112
1 files changed, 112 insertions, 0 deletions
diff --git a/lib/fclose.c b/lib/fclose.c
new file mode 100644
index 0000000..2ac577d
--- /dev/null
+++ b/lib/fclose.c
@@ -0,0 +1,112 @@
+/* fclose replacement.
+ Copyright (C) 2008-2020 Free Software Foundation, Inc.
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+#include <config.h>
+
+/* Specification. */
+#include <stdio.h>
+
+#include <errno.h>
+#include <unistd.h>
+
+#include "freading.h"
+#if HAVE_MSVC_INVALID_PARAMETER_HANDLER
+# include "msvc-inval.h"
+#endif
+
+#undef fclose
+
+#if HAVE_MSVC_INVALID_PARAMETER_HANDLER
+static int
+fclose_nothrow (FILE *fp)
+{
+ int result;
+
+ TRY_MSVC_INVAL
+ {
+ result = fclose (fp);
+ }
+ CATCH_MSVC_INVAL
+ {
+ result = EOF;
+ errno = EBADF;
+ }
+ DONE_MSVC_INVAL;
+
+ return result;
+}
+#else
+# define fclose_nothrow fclose
+#endif
+
+/* Override fclose() to call the overridden fflush() or close(). */
+
+int
+rpl_fclose (FILE *fp)
+{
+ int saved_errno = 0;
+ int fd;
+ int result = 0;
+
+ /* Don't change behavior on memstreams. */
+ fd = fileno (fp);
+ if (fd < 0)
+ return fclose_nothrow (fp);
+
+ /* We only need to flush the file if it is not reading or if it is
+ seekable. This only guarantees the file position of input files
+ if the fflush module is also in use. */
+ if ((!freading (fp) || lseek (fileno (fp), 0, SEEK_CUR) != -1)
+ && fflush (fp))
+ saved_errno = errno;
+
+ /* fclose() calls close(), but we need to also invoke all hooks that our
+ overridden close() function invokes. See lib/close.c. */
+#if WINDOWS_SOCKETS
+ /* Call the overridden close(), then the original fclose().
+ Note about multithread-safety: There is a race condition where some
+ other thread could open fd between our close and fclose. */
+ if (close (fd) < 0 && saved_errno == 0)
+ saved_errno = errno;
+
+ fclose_nothrow (fp); /* will fail with errno = EBADF,
+ if we did not lose a race */
+
+#else /* !WINDOWS_SOCKETS */
+ /* Call fclose() and invoke all hooks of the overridden close(). */
+
+# if REPLACE_FCHDIR
+ /* Note about multithread-safety: There is a race condition here as well.
+ Some other thread could open fd between our calls to fclose and
+ _gl_unregister_fd. */
+ result = fclose_nothrow (fp);
+ if (result == 0)
+ _gl_unregister_fd (fd);
+# else
+ /* No race condition here. */
+ result = fclose_nothrow (fp);
+# endif
+
+#endif /* !WINDOWS_SOCKETS */
+
+ if (saved_errno != 0)
+ {
+ errno = saved_errno;
+ result = EOF;
+ }
+
+ return result;
+}