1 /* Check static buffer handling with setvbuf (BZ #22415)
2
3 Copyright (C) 2017-2022 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
5
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
10
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <https://www.gnu.org/licenses/>. */
19
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <wchar.h>
23 #include <mcheck.h>
24
25 #include <support/check.h>
26 #include <support/temp_file.h>
27
28 static int
do_test(void)29 do_test (void)
30 {
31 mtrace ();
32
33 char *temp_file;
34 TEST_VERIFY_EXIT (create_temp_file ("tst-bz22145.", &temp_file));
35
36 char buf[BUFSIZ];
37
38 {
39 /* Check if backup buffer is correctly freed and changing back
40 to normal buffer does not trigger an invalid free in case of
41 static buffer set by setvbuf. */
42
43 FILE *f = fopen (temp_file, "w+b");
44 TEST_VERIFY_EXIT (f != NULL);
45
46 TEST_VERIFY_EXIT (setvbuf (f, buf, _IOFBF, BUFSIZ) == 0);
47 TEST_VERIFY_EXIT (ungetc ('x', f) == 'x');
48 TEST_VERIFY_EXIT (fseek (f, 0L, SEEK_SET) == 0);
49 TEST_VERIFY_EXIT (fputc ('y', f) == 'y');
50
51 TEST_VERIFY_EXIT (fclose (f) == 0);
52 }
53
54 {
55 /* Check if backup buffer is correctly freed and changing back
56 to normal buffer does not trigger an invalid free in case of
57 static buffer set by setvbuf. */
58
59 FILE *f = fopen (temp_file, "w+b");
60 TEST_VERIFY_EXIT (f != NULL);
61
62 TEST_VERIFY_EXIT (setvbuf (f, buf, _IOFBF, BUFSIZ) == 0);
63 TEST_VERIFY_EXIT (ungetc ('x', f) == 'x');
64 TEST_VERIFY_EXIT (fputc ('y', f) == 'y');
65
66 TEST_VERIFY_EXIT (fclose (f) == 0);
67 }
68
69 {
70 FILE *f = fopen (temp_file, "w+b");
71 TEST_VERIFY_EXIT (f != NULL);
72
73 TEST_VERIFY_EXIT (setvbuf (f, buf, _IOFBF, BUFSIZ) == 0);
74 TEST_VERIFY_EXIT (ungetwc (L'x', f) == L'x');
75 TEST_VERIFY_EXIT (fseek (f, 0L, SEEK_SET) == 0);
76 TEST_VERIFY_EXIT (fputwc (L'y', f) == L'y');
77
78 TEST_VERIFY_EXIT (fclose (f) == 0);
79 }
80
81 {
82 FILE *f = fopen (temp_file, "w+b");
83 TEST_VERIFY_EXIT (f != NULL);
84
85 TEST_VERIFY_EXIT (setvbuf (f, buf, _IOFBF, BUFSIZ) == 0);
86 TEST_VERIFY_EXIT (ungetwc (L'x', f) == L'x');
87 TEST_VERIFY_EXIT (fputwc (L'y', f) == L'y');
88
89 TEST_VERIFY_EXIT (fclose (f) == 0);
90 }
91
92 free (temp_file);
93
94 return 0;
95 }
96
97 #include <support/test-driver.c>
98