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Diffstat (limited to 'gnulib-tests/test-fflush.c')
| -rw-r--r-- | gnulib-tests/test-fflush.c | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/gnulib-tests/test-fflush.c b/gnulib-tests/test-fflush.c new file mode 100644 index 0000000..cf61905 --- /dev/null +++ b/gnulib-tests/test-fflush.c @@ -0,0 +1,191 @@ +/* Test of POSIX compatible fflush() function. + Copyright (C) 2007, 2009-2020 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/>. */ + +/* Written by Eric Blake, 2007. */ + +#include <config.h> + +/* None of the files accessed by this test are large, so disable the + ftell link warning if we are not using the gnulib ftell module. */ +#define _GL_NO_LARGE_FILES +#include <stdio.h> + +#include "signature.h" +SIGNATURE_CHECK (fflush, int, (FILE *)); + +#include <errno.h> +#include <unistd.h> + +#include "macros.h" + +int +main (void) +{ + FILE *f; + char buffer[10]; + int fd; + + /* Create test file. */ + f = fopen ("test-fflush.txt", "w"); + if (!f || fwrite ("1234567890ABCDEFG", 1, 17, f) != 17 || fclose (f) != 0) + { + fputs ("Failed to create sample file.\n", stderr); + unlink ("test-fflush.txt"); + return 1; + } + + /* Test fflush. */ + f = fopen ("test-fflush.txt", "r"); + ASSERT (f != NULL); + fd = fileno (f); + if (!f || 0 > fd || fread (buffer, 1, 5, f) != 5) + { + fputs ("Failed initial read of sample file.\n", stderr); + if (f) + fclose (f); + unlink ("test-fflush.txt"); + return 1; + } + /* For deterministic results, ensure f read a bigger buffer. + This is not the case on BeOS, nor on uClibc. */ +#if !(defined __BEOS__ || defined __UCLIBC__) + if (lseek (fd, 0, SEEK_CUR) == 5) + { + fputs ("Sample file was not buffered after fread.\n", stderr); + fclose (f); + unlink ("test-fflush.txt"); + return 1; + } +#endif + /* POSIX requires fflush-fseek to set file offset of fd. */ + if (fflush (f) != 0 || fseeko (f, 0, SEEK_CUR) != 0) + { + fputs ("Failed to flush-fseek sample file.\n", stderr); + fclose (f); + unlink ("test-fflush.txt"); + return 1; + } + /* Check that offset is correct. */ + if (lseek (fd, 0, SEEK_CUR) != 5) + { + fprintf (stderr, "File offset is wrong after fseek: %ld.\n", + (long) lseek (fd, 0, SEEK_CUR)); + fclose (f); + unlink ("test-fflush.txt"); + return 1; + } + if (ftell (f) != 5) + { + fprintf (stderr, "ftell result is wrong after fseek: %ld.\n", + (long) ftell (f)); + fclose (f); + unlink ("test-fflush.txt"); + return 1; + } + /* Check that file reading resumes at correct location. */ + if (fgetc (f) != '6') + { + fputs ("Failed to read next byte after fseek.\n", stderr); + fclose (f); + unlink ("test-fflush.txt"); + return 1; + } + /* For deterministic results, ensure f read a bigger buffer. */ + if (lseek (fd, 0, SEEK_CUR) == 6) + { + fputs ("Sample file was not buffered after fgetc.\n", stderr); + fclose (f); + unlink ("test-fflush.txt"); + return 1; + } + /* POSIX requires fflush-fseeko to set file offset of fd. */ + if (fflush (f) != 0 || fseeko (f, 0, SEEK_CUR) != 0) + { + fputs ("Failed to flush-fseeko sample file.\n", stderr); + fclose (f); + unlink ("test-fflush.txt"); + return 1; + } + /* Check that offset is correct. */ + if (lseek (fd, 0, SEEK_CUR) != 6) + { + fprintf (stderr, "File offset is wrong after fseeko: %ld.\n", + (long) lseek (fd, 0, SEEK_CUR)); + fclose (f); + unlink ("test-fflush.txt"); + return 1; + } + if (ftell (f) != 6) + { + fprintf (stderr, "ftell result is wrong after fseeko: %ld.\n", + (long) ftell (f)); + fclose (f); + unlink ("test-fflush.txt"); + return 1; + } + /* Check that file reading resumes at correct location. */ + if (fgetc (f) != '7') + { + fputs ("Failed to read next byte after fseeko.\n", stderr); + fclose (f); + unlink ("test-fflush.txt"); + return 1; + } + fclose (f); + + /* Test that fflush() sets errno if someone else closes the stream + fd behind the back of stdio. */ + { + FILE *fp = fopen ("test-fflush.txt", "w"); + ASSERT (fp != NULL); + fputc ('x', fp); + ASSERT (close (fileno (fp)) == 0); + errno = 0; + ASSERT (fflush (fp) == EOF); + ASSERT (errno == EBADF); + fclose (fp); + } + + /* Test that fflush() sets errno if the stream was constructed with + an invalid file descriptor. */ + { + FILE *fp = fdopen (-1, "w"); + if (fp != NULL) + { + fputc ('x', fp); + errno = 0; + ASSERT (fflush (fp) == EOF); + ASSERT (errno == EBADF); + } + } + { + FILE *fp; + close (99); + fp = fdopen (99, "w"); + if (fp != NULL) + { + fputc ('x', fp); + errno = 0; + ASSERT (fflush (fp) == EOF); + ASSERT (errno == EBADF); + } + } + + /* Clean up. */ + unlink ("test-fflush.txt"); + + return 0; +} |