1/* Copyright (C) 1991-2024 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18#include <assert.h>
19#include <atomic.h>
20#include <ldsodefs.h>
21#include <libc-pointer-arith.h>
22#include <libintl.h>
23#include <stdio.h>
24#include <stdlib.h>
25#include <sysdep.h>
26#include <unistd.h>
27#include <sys/mman.h>
28#include <setvmaname.h>
29
30
31extern const char *__progname;
32
33#include <wchar.h>
34#include <libio/iolibio.h>
35#define fflush(s) _IO_fflush (s)
36
37/* This function, when passed a string containing an asserted
38 expression, a filename, and a line number, prints a message
39 on the standard error stream of the form:
40 a.c:10: foobar: Assertion `a == b' failed.
41 It then aborts program execution via a call to `abort'. */
42
43#ifdef FATAL_PREPARE_INCLUDE
44# include FATAL_PREPARE_INCLUDE
45#endif
46
47
48void
49__assert_fail_base (const char *fmt, const char *assertion, const char *file,
50 unsigned int line, const char *function)
51{
52 char *str;
53
54#ifdef FATAL_PREPARE
55 FATAL_PREPARE;
56#endif
57
58 int total;
59 if (__asprintf (&str, fmt,
60 __progname, __progname[0] ? ": " : "",
61 file, line,
62 function ? function : "", function ? ": " : "",
63 assertion, &total) >= 0)
64 {
65 /* Print the message. */
66 (void) __fxprintf (NULL, fmt: "%s", str);
67 (void) fflush (stderr);
68
69 total = ALIGN_UP (total + sizeof (struct abort_msg_s) + 1,
70 GLRO(dl_pagesize));
71 struct abort_msg_s *buf = __mmap (NULL, total, PROT_READ | PROT_WRITE,
72 MAP_ANON | MAP_PRIVATE, -1, 0);
73 if (__glibc_likely (buf != MAP_FAILED))
74 {
75 buf->size = total;
76 strcpy (buf->msg, str);
77 __set_vma_name (start: buf, len: total, name: " glibc: assert");
78
79 /* We have to free the old buffer since the application might
80 catch the SIGABRT signal. */
81 struct abort_msg_s *old = atomic_exchange_acquire (&__abort_msg, buf);
82
83 if (old != NULL)
84 __munmap (old, old->size);
85 }
86
87 free (ptr: str);
88 }
89 else
90 {
91 /* At least print a minimal message. */
92 static const char errstr[] = "Unexpected error.\n";
93 __libc_write (STDERR_FILENO, errstr, sizeof (errstr) - 1);
94 }
95
96 abort ();
97}
98
99
100#undef __assert_fail
101void
102__assert_fail (const char *assertion, const char *file, unsigned int line,
103 const char *function)
104{
105 __assert_fail_base (_("%s%s%s:%u: %s%sAssertion `%s' failed.\n%n"),
106 assertion, file, line, function);
107}
108

source code of glibc/assert/assert.c