diff options
| -rw-r--r-- | libio/genops.c | 7 | ||||
| -rw-r--r-- | stdio-common/Makefile | 1 | ||||
| -rw-r--r-- | stdio-common/tst-fflush-all-input.c | 94 |
3 files changed, 102 insertions, 0 deletions
diff --git a/libio/genops.c b/libio/genops.c index 2197bfe..e4378ca 100644 --- a/libio/genops.c +++ b/libio/genops.c @@ -730,6 +730,13 @@ _IO_flush_all (void) ) && _IO_OVERFLOW (fp, EOF) == EOF) result = EOF; + if (_IO_fileno (fp) >= 0 + && ((fp->_mode <= 0 && fp->_IO_read_ptr < fp->_IO_read_end) + || (_IO_vtable_offset (fp) == 0 + && fp->_mode > 0 && (fp->_wide_data->_IO_read_ptr + < fp->_wide_data->_IO_read_end))) + && _IO_SYNC (fp) != 0) + result = EOF; _IO_funlockfile (fp); run_fp = NULL; diff --git a/stdio-common/Makefile b/stdio-common/Makefile index f6bdc32..26c1b88 100644 --- a/stdio-common/Makefile +++ b/stdio-common/Makefile @@ -238,6 +238,7 @@ tests := \ tst-fdopen \ tst-fdopen2 \ tst-ferror \ + tst-fflush-all-input \ tst-fgets \ tst-fgets2 \ tst-fileno \ diff --git a/stdio-common/tst-fflush-all-input.c b/stdio-common/tst-fflush-all-input.c new file mode 100644 index 0000000..8e3fca3 --- /dev/null +++ b/stdio-common/tst-fflush-all-input.c @@ -0,0 +1,94 @@ +/* Test fflush (NULL) flushes input files (bug 32369). + Copyright (C) 2025 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library 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. + + The GNU C Library 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 the GNU C Library; if not, see + <https://www.gnu.org/licenses/>. */ + +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <wchar.h> + +#include <support/check.h> +#include <support/xstdio.h> +#include <support/xunistd.h> + +int +do_test (void) +{ + FILE *temp = tmpfile (); + TEST_VERIFY_EXIT (temp != NULL); + fprintf (temp, "abc"); + TEST_COMPARE (fflush (temp), 0); + TEST_COMPARE (lseek (fileno (temp), 0, SEEK_SET), 0); + TEST_COMPARE (fgetc (temp), 'a'); + TEST_COMPARE (fflush (NULL), 0); + TEST_COMPARE (lseek (fileno (temp), 0, SEEK_CUR), 1); + xfclose (temp); + + /* Likewise, but in wide mode. */ + temp = tmpfile (); + TEST_VERIFY_EXIT (temp != NULL); + fwprintf (temp, L"abc"); + TEST_COMPARE (fflush (temp), 0); + TEST_COMPARE (lseek (fileno (temp), 0, SEEK_SET), 0); + TEST_COMPARE (fgetwc (temp), L'a'); + TEST_COMPARE (fflush (NULL), 0); + TEST_COMPARE (lseek (fileno (temp), 0, SEEK_CUR), 1); + xfclose (temp); + + /* Similar tests, but with the flush implicitly occurring on exit + (in a forked subprocess). */ + + temp = tmpfile (); + TEST_VERIFY_EXIT (temp != NULL); + pid_t pid = xfork (); + if (pid == 0) + { + fprintf (temp, "abc"); + TEST_COMPARE (fflush (temp), 0); + TEST_COMPARE (lseek (fileno (temp), 0, SEEK_SET), 0); + TEST_COMPARE (fgetc (temp), 'a'); + exit (EXIT_SUCCESS); + } + else + { + TEST_COMPARE (xwaitpid (pid, NULL, 0), pid); + TEST_COMPARE (lseek (fileno (temp), 0, SEEK_CUR), 1); + xfclose (temp); + } + + temp = tmpfile (); + TEST_VERIFY_EXIT (temp != NULL); + pid = xfork (); + if (pid == 0) + { + fwprintf (temp, L"abc"); + TEST_COMPARE (fflush (temp), 0); + TEST_COMPARE (lseek (fileno (temp), 0, SEEK_SET), 0); + TEST_COMPARE (fgetwc (temp), L'a'); + exit (EXIT_SUCCESS); + } + else + { + TEST_COMPARE (xwaitpid (pid, NULL, 0), pid); + TEST_COMPARE (lseek (fileno (temp), 0, SEEK_CUR), 1); + xfclose (temp); + } + + return 0; +} + +#include <support/test-driver.c> |