summaryrefslogtreecommitdiffstats
path: root/lib/strsignal.c
blob: 4db5014c1785a2ca128eacf786f75c15d4e1d0d3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
/* Copyright (C) 1991, 1994-2002, 2005, 2008-2022 Free Software Foundation,
   Inc.
   This file is part of the GNU C Library.

   This file 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.

   This file 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 this program.  If not, see <https://www.gnu.org/licenses/>.  */

#ifndef _LIBC
# include <config.h>
#endif

/* Specification.  */
#include <string.h>

#include <signal.h>
#include <stdio.h>
#include <stdlib.h>

#ifdef _LIBC
# include <libintl.h>
#else /* !_LIBC */
# include "gettext.h"
# define _(msgid) gettext (msgid)
# define N_(msgid) gettext_noop (msgid)
#endif /* _LIBC */

#ifdef _LIBC
# include <bits/libc-lock.h>
#else /* !_LIBC */
# include "glthread/lock.h"
# include "glthread/tls.h"
# define __libc_once_define(CLASS, NAME) gl_once_define (CLASS, NAME)
# define __libc_once(NAME, INIT) gl_once ((NAME), (INIT))
# define __libc_key_t gl_tls_key_t
# define __libc_getspecific(NAME) gl_tls_get ((NAME))
# define __libc_setspecific(NAME, POINTER) gl_tls_set ((NAME), (POINTER))
# define __snprintf snprintf
#endif /* _LIBC */

#ifdef _LIBC

/* Defined in siglist.c.  */
extern const char *const _sys_siglist[];
extern const char *const _sys_siglist_internal[] attribute_hidden;

#else /* !_LIBC */

/* NetBSD declares sys_siglist in unistd.h. */
# if HAVE_UNISTD_H
#  include <unistd.h>
# endif

# define INTUSE(x) (x)

# if HAVE_DECL_SYS_SIGLIST
#  undef _sys_siglist
#  define _sys_siglist sys_siglist
# else /* !HAVE_DECL_SYS_SIGLIST */
#  ifndef NSIG
#   define NSIG 32
#  endif /* NSIG */
#  if !HAVE_DECL__SYS_SIGLIST
static const char *_sys_siglist[NSIG];
#  endif
# endif /* !HAVE_DECL_SYS_SIGLIST */

#endif /* _LIBC */

static __libc_key_t key;

/* If nonzero the key allocation failed and we should better use a
   static buffer than fail.  */
#define BUFFERSIZ       100
static char local_buf[BUFFERSIZ];
static char *static_buf;

/* Destructor for the thread-specific data.  */
static void init (void);
static void free_key_mem (void *mem);
static char *getbuffer (void);


/* Return a string describing the meaning of the signal number SIGNUM.  */
char *
strsignal (int signum)
{
  const char *desc;
  __libc_once_define (static, once);

  /* If we have not yet initialized the buffer do it now.  */
  __libc_once (once, init);

  if (
#ifdef SIGRTMIN
      (signum >= SIGRTMIN && signum <= SIGRTMAX) ||
#endif
      signum < 0 || signum >= NSIG
      || (desc = INTUSE(_sys_siglist)[signum]) == NULL)
    {
      char *buffer = getbuffer ();
      int len;
#ifdef SIGRTMIN
      if (signum >= SIGRTMIN && signum <= SIGRTMAX)
        len = __snprintf (buffer, BUFFERSIZ - 1, _("Real-time signal %d"),
                          signum - (int) SIGRTMIN);
      else
#endif
        len = __snprintf (buffer, BUFFERSIZ - 1, _("Unknown signal %d"),
                          signum);
      if (len >= BUFFERSIZ)
        buffer = NULL;
      else
        buffer[len] = '\0';

      return buffer;
    }

  return (char *) _(desc);
}


/* Initialize buffer.  */
static void
init (void)
{
#ifdef _LIBC
  if (__libc_key_create (&key, free_key_mem))
    /* Creating the key failed.  This means something really went
       wrong.  In any case use a static buffer which is better than
       nothing.  */
    static_buf = local_buf;
#else /* !_LIBC */
  gl_tls_key_init (key, free_key_mem);

# if !HAVE_DECL_SYS_SIGLIST
  memset (_sys_siglist, 0, NSIG * sizeof *_sys_siglist);

  /* No need to use a do {} while (0) here since init_sig(...) must expand
     to a complete statement.  (We cannot use the ISO C99 designated array
     initializer syntax since it is not supported by ANSI C compilers and
     since some signal numbers might exceed NSIG.)  */
#  define init_sig(sig, abbrev, desc) \
  if (sig >= 0 && sig < NSIG) \
    _sys_siglist[sig] = desc;

#  include "siglist.h"

#  undef init_sig

# endif /* !HAVE_DECL_SYS_SIGLIST */
#endif /* !_LIBC */
}


/* Free the thread specific data, this is done if a thread terminates.  */
static void
free_key_mem (void *mem)
{
  free (mem);
  __libc_setspecific (key, NULL);
}


/* Return the buffer to be used.  */
static char *
getbuffer (void)
{
  char *result;

  if (static_buf != NULL)
    result = static_buf;
  else
    {
      /* We don't use the static buffer and so we have a key.  Use it
         to get the thread-specific buffer.  */
      result = __libc_getspecific (key);
      if (result == NULL)
        {
          /* No buffer allocated so far.  */
          result = malloc (BUFFERSIZ);
          if (result == NULL)
            /* No more memory available.  We use the static buffer.  */
            result = local_buf;
          else
            __libc_setspecific (key, result);
        }
    }

  return result;
}