| /* 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; |
| } |