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authorLi Jinjing <jinjingx.li@intel.com>2014-10-26 22:28:15 +0800
committerLi Jinjing <jinjingx.li@intel.com>2014-10-26 22:28:15 +0800
commit931b01b091932a1f796c23379ea32abb68bd5895 (patch)
tree3aa9e1125da84f7e3bd764bbff577c42a766508b /lib/fclose.c
parent7be93f2d05131d061bd4790ae33c8d50f50010d7 (diff)
downloadm4-931b01b091932a1f796c23379ea32abb68bd5895.tar.gz
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Imported Upstream version 1.4.17upstream/1.4.17sandbox/jinjingx/upstream
Diffstat (limited to 'lib/fclose.c')
-rw-r--r--lib/fclose.c79
1 files changed, 71 insertions, 8 deletions
diff --git a/lib/fclose.c b/lib/fclose.c
index 1d7e85b..90ed653 100644
--- a/lib/fclose.c
+++ b/lib/fclose.c
@@ -1,5 +1,5 @@
/* fclose replacement.
- Copyright (C) 2008-2011 Free Software Foundation, Inc.
+ Copyright (C) 2008-2013 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
@@ -22,26 +22,89 @@
#include <errno.h>
#include <unistd.h>
-/* Override fclose() to call the overridden close(). */
+#include "freading.h"
+#include "msvc-inval.h"
+
+#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)
-#undef fclose
{
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);
- if (fflush (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;
- if (close (fileno (fp)) < 0 && saved_errno == 0)
+ /* 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 (fp); /* will fail with errno = EBADF */
+ 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;
- return EOF;
+ result = EOF;
}
- return 0;
+
+ return result;
}