Mercurial > hg > octave-lojdl > gnulib-hg
changeset 14678:68c96ae4be1a
fflush: also replace fclose when fixing fflush
This fixes the fclose failures detected in the previous patch,
but only when the GPL fflush module is also in use. That is
because the need for behavior of resetting seekable input streams
is much less common, and the fix more complex. The LGPLv2+ test
for fclose() in isolation is relaxed to pass if fflush is not
being replaced to cater to input streams.
* modules/fflush (Depends-on): Add fclose.
* m4/fflush.m4 (gl_FUNC_FFLUSH): Also replace fclose.
* lib/fclose.c (rpl_fclose): Don't cause spurious failures on
memstreams with no backing fd.
* doc/posix-functions/fclose.texi (fclose): Document the use of
fflush module to fix the bug.
* tests/test-fclose.c (main): Relax test when fclose is used in
isolation.
Signed-off-by: Eric Blake <eblake@redhat.com>
author | Eric Blake <eblake@redhat.com> |
---|---|
date | Mon, 02 May 2011 15:00:50 -0600 |
parents | fa93679417c1 |
children | 2c310adf09e5 |
files | ChangeLog doc/posix-functions/fclose.texi lib/fclose.c m4/fflush.m4 modules/fflush tests/test-fclose.c |
diffstat | 6 files changed, 36 insertions(+), 10 deletions(-) [+] |
line wrap: on
line diff
--- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,15 @@ 2011-05-02 Eric Blake <eblake@redhat.com> + fflush: also replace fclose when fixing fflush + * modules/fflush (Depends-on): Add fclose. + * m4/fflush.m4 (gl_FUNC_FFLUSH): Also replace fclose. + * lib/fclose.c (rpl_fclose): Don't cause spurious failures on + memstreams with no backing fd. + * doc/posix-functions/fclose.texi (fclose): Document the use of + fflush module to fix the bug. + * tests/test-fclose.c (main): Relax test when fclose is used in + isolation. + fclose: add some tests * modules/fclose-tests: New test module. * tests/test-fclose.c: New file.
--- a/doc/posix-functions/fclose.texi +++ b/doc/posix-functions/fclose.texi @@ -4,9 +4,17 @@ POSIX specification:@* @url{http://www.opengroup.org/onlinepubs/9699919799/functions/fclose.html} -Gnulib module: fclose +Gnulib module: fclose, fflush -Portability problems fixed by Gnulib: +Portability problems fixed by Gnulib module @code{fflush}: +@itemize +@item +On some platforms, this function fails to set the file position of a +seekable input stream to the byte after the last one actually read: +glibc 2.13, FreeBSD. +@end itemize + +Portability problems fixed by Gnulib module @code{fclose}: @itemize @item On Windows platforms (excluding Cygwin), @code{socket} and @code{accept} @@ -17,10 +25,6 @@ Portability problems not fixed by Gnulib: @itemize @item -On some platforms, this function fails to set the file position of a -seekable input stream to the byte after the last one actually read: -glibc 2.13, FreeBSD. -@item On Windows platforms (excluding Cygwin), this function does not set @code{errno} upon failure. @end itemize
--- a/lib/fclose.c +++ b/lib/fclose.c @@ -24,13 +24,19 @@ #include "freading.h" -/* Override fclose() to call the overridden close(). */ +/* Override fclose() to call the overridden fflush() or close(). */ int rpl_fclose (FILE *fp) #undef fclose { int saved_errno = 0; + int fd; + + /* Don't change behavior on memstreams. */ + fd = fileno (fp); + if (fd < 0) + return fclose (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 @@ -39,7 +45,7 @@ && fflush (fp)) saved_errno = errno; - if (close (fileno (fp)) < 0 && saved_errno == 0) + if (close (fd) < 0 && saved_errno == 0) saved_errno = errno; fclose (fp); /* will fail with errno = EBADF */
--- a/m4/fflush.m4 +++ b/m4/fflush.m4 @@ -1,4 +1,4 @@ -# fflush.m4 serial 8 +# fflush.m4 serial 9 # Copyright (C) 2007-2011 Free Software Foundation, Inc. # This file is free software; the Free Software Foundation @@ -61,6 +61,7 @@ ]) if test $gl_cv_func_fflush_stdin = no; then gl_REPLACE_FFLUSH + gl_REPLACE_FCLOSE fi ])
--- a/modules/fflush +++ b/modules/fflush @@ -7,6 +7,7 @@ m4/fflush.m4 Depends-on: +fclose fpurge ftello freading @@ -20,6 +21,7 @@ configure.ac: gl_FUNC_FFLUSH +gl_MODULE_INDICATOR([fflush]) gl_STDIO_MODULE_INDICATOR([fflush]) Makefile.am:
--- a/tests/test-fclose.c +++ b/tests/test-fclose.c @@ -62,7 +62,9 @@ ASSERT (errno == EBADF); ASSERT (lseek (fd, 0, SEEK_CUR) == 2); - /* Likewise for an input stream. */ +#if GNULIB_FFLUSH + /* Likewise for an input stream, but only when we know fflush works + on input streams. */ fd2 = dup (fd); ASSERT (0 <= fd2); f = fdopen (fd2, "r"); @@ -73,6 +75,7 @@ ASSERT (lseek (fd2, 0, SEEK_CUR) == -1); ASSERT (errno == EBADF); ASSERT (lseek (fd, 0, SEEK_CUR) == 3); +#endif /* Test that fclose() sets errno if someone else closes the stream fd behind the back of stdio. */