/* strerror_r.c --- POSIX compatible system error routine
Copyright (C) 2010-2017 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 <http://www.gnu.org/licenses/>. */
/* Written by Bruno Haible <bruno@clisp.org>, 2010. */
#include <config.h>
/* Enable declaration of sys_nerr and sys_errlist in <errno.h> on NetBSD. */
#define _NETBSD_SOURCE 1
/* Specification. */
#include <string.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#if !HAVE_SNPRINTF
# include <stdarg.h>
#endif
#include "strerror-override.h"
#if (__GLIBC__ >= 2 || defined __UCLIBC__ || defined __CYGWIN__) && HAVE___XPG_STRERROR_R /* glibc >= 2.3.4, cygwin >= 1.7.9 */
# define USE_XPG_STRERROR_R 1
extern
#ifdef __cplusplus
"C"
#endif
int __xpg_strerror_r (int errnum, char *buf, size_t buflen);
#elif HAVE_DECL_STRERROR_R && !(__GLIBC__ >= 2 || defined __UCLIBC__ || defined __CYGWIN__)
/* The system's strerror_r function is OK, except that its third argument
is 'int', not 'size_t', or its return type is wrong. */
# include <limits.h>
# define USE_SYSTEM_STRERROR_R 1
#else /* (__GLIBC__ >= 2 || defined __UCLIBC__ || defined __CYGWIN__ ? !HAVE___XPG_STRERROR_R : !HAVE_DECL_STRERROR_R) */
/* Use the system's strerror(). Exclude glibc and cygwin because the
system strerror_r has the wrong return type, and cygwin 1.7.9
strerror_r clobbers strerror. */
# undef strerror
# define USE_SYSTEM_STRERROR 1
# if defined __NetBSD__ || defined __hpux || ((defined _WIN32 || defined __WIN32__) && !defined __CYGWIN__) || defined __sgi || (defined __sun && !defined _LP64) || defined __CYGWIN__
/* No locking needed. */
/* Get catgets internationalization functions. */
# if HAVE_CATGETS
# include <nl_types.h>
# endif
#ifdef __cplusplus
extern "C" {
#endif
/* Get sys_nerr, sys_errlist on HP-UX (otherwise only declared in C++ mode).
Get sys_nerr, sys_errlist on IRIX (otherwise only declared with _SGIAPI). */
# if defined __hpux || defined __sgi
extern int sys_nerr;
extern char *sys_errlist[];
# endif
/* Get sys_nerr on Solaris. */
# if defined __sun && !defined _LP64
extern int sys_nerr;
# endif
#ifdef __cplusplus
}
#endif
# else
# include "glthread/lock.h"
/* This lock protects the buffer returned by strerror(). We assume that
no other uses of strerror() exist in the program. */
gl_lock_define_initialized(static, strerror_lock)
# endif
#endif
/* On MSVC, there is no snprintf() function, just a _snprintf().
It is of lower quality, but sufficient for the simple use here.
We only have to make sure to NUL terminate the result (_snprintf
does not NUL terminate, like strncpy). */
#if !HAVE_SNPRINTF
static int
local_snprintf (char *buf, size_t buflen, const char *format, ...)
{
va_list args;
int result;
va_start (args, format);
result = _vsnprintf (buf, buflen, format, args);
va_end (args);
if (buflen > 0 && (result < 0 || result >= buflen))
buf[buflen - 1] = '\0';
return result;
}
# define snprintf local_snprintf
#endif
/* Copy as much of MSG into BUF as possible, without corrupting errno.
Return 0 if MSG fit in BUFLEN, otherwise return ERANGE. */
static int
safe_copy (char *buf, size_t buflen, const char *msg)
{
size_t len = strlen (msg);
int ret;
if (len < buflen)
{
/* Although POSIX allows memcpy() to corrupt errno, we don't
know of any implementation where this is a real problem. */
memcpy (buf, msg, len + 1);
ret = 0;
}
else
{
memcpy (buf, msg, buflen - 1);
buf[buflen - 1] = '\0';
ret = ERANGE;
}
return ret;
}
int
strerror_r (int errnum, char *buf, size_t buflen)
#undef strerror_r
{
/* Filter this out now, so that rest of this replacement knows that
there is room for a non-empty message and trailing NUL. */
if (buflen <= 1)
{
if (buflen)
*buf = '\0';
return ERANGE;
}
*buf = '\0';
/* Check for gnulib overrides. */
{
char const *msg = strerror_override (errnum);
if (msg)
return safe_copy (buf, buflen, msg);
}
{
int ret;
int saved_errno = errno;
#if USE_XPG_STRERROR_R
{
ret = __xpg_strerror_r (errnum, buf, buflen);
if (ret < 0)
ret = errno;
if (!*buf)
{
/* glibc 2.13 would not touch buf on err, so we have to fall
back to GNU strerror_r which always returns a thread-safe
untruncated string to (partially) copy into our buf. */
safe_copy (buf, buflen, strerror_r (errnum, buf, buflen));
}
}
#elif USE_SYSTEM_STRERROR_R
if (buflen > INT_MAX)
buflen = INT_MAX;
# ifdef __hpux
/* On HP-UX 11.31, strerror_r always fails when buflen < 80; it
also fails to change buf on EINVAL. */
{
char stackbuf[80];
if (buflen < sizeof stackbuf)
{
ret = strerror_r (errnum, stackbuf, sizeof stackbuf);
if (ret == 0)
ret = safe_copy (buf, buflen, stackbuf);
}
else
ret = strerror_r (errnum, buf, buflen);
}
# else
ret = strerror_r (errnum, buf, buflen);
/* Some old implementations may return (-1, EINVAL) instead of EINVAL. */
if (ret < 0)
ret = errno;
# endif
# ifdef _AIX
/* AIX returns 0 rather than ERANGE when truncating strings; try
again until we are sure we got the entire string. */
if (!ret && strlen (buf) == buflen - 1)
{
char stackbuf[STACKBUF_LEN];
size_t len;
strerror_r (errnum, stackbuf, sizeof stackbuf);
len = strlen (stackbuf);
/* STACKBUF_LEN should have been large enough. */
if (len + 1 == sizeof stackbuf)
abort ();
if (buflen <= len)
ret = ERANGE;
}
# else
/* Solaris 10 does not populate buf on ERANGE. OpenBSD 4.7
truncates early on ERANGE rather than return a partial integer.
We prefer the maximal string. We set buf[0] earlier, and we
know of no implementation that modifies buf to be an
unterminated string, so this strlen should be portable in
practice (rather than pulling in a safer strnlen). */
if (ret == ERANGE && strlen (buf) < buflen - 1)
{
char stackbuf[STACKBUF_LEN];
/* STACKBUF_LEN should have been large enough. */
if (strerror_r (errnum, stackbuf, sizeof stackbuf) == ERANGE)
abort ();
safe_copy (buf, buflen, stackbuf);
}
# endif
#else /* USE_SYSTEM_STRERROR */
/* Try to do what strerror (errnum) does, but without clobbering the
buffer used by strerror(). */
# if defined __NetBSD__ || defined __hpux || ((defined _WIN32 || defined __WIN32__) && !defined __CYGWIN__) || defined __CYGWIN__ /* NetBSD, HP-UX, native Windows, Cygwin */
/* NetBSD: sys_nerr, sys_errlist are declared through _NETBSD_SOURCE
and <errno.h> above.
HP-UX: sys_nerr, sys_errlist are declared explicitly above.
native Windows: sys_nerr, sys_errlist are declared in <stdlib.h>.
Cygwin: sys_nerr, sys_errlist are declared in <errno.h>. */
if (errnum >= 0 && errnum < sys_nerr)
{
# if HAVE_CATGETS && (defined __NetBSD__ || defined __hpux)
# if defined __NetBSD__
nl_catd catd = catopen ("libc", NL_CAT_LOCALE);
const char *errmsg =
(catd != (nl_catd)-1
? catgets (catd, 1, errnum, sys_errlist[errnum])
: sys_errlist[errnum]);
# endif
# if defined __hpux
nl_catd catd = catopen ("perror", NL_CAT_LOCALE);
const char *errmsg =
(catd != (nl_catd)-1
? catgets (catd, 1, 1 + errnum, sys_errlist[errnum])
: sys_errlist[errnum]);
# endif
# else
const char *errmsg = sys_errlist[errnum];
# endif
if (errmsg == NULL || *errmsg == '\0')
ret = EINVAL;
else
ret = safe_copy (buf, buflen, errmsg);
# if HAVE_CATGETS && (defined __NetBSD__ || defined __hpux)
if (catd != (nl_catd)-1)
catclose (catd);
# endif
}
else
ret = EINVAL;
# elif defined __sgi || (defined __sun && !defined _LP64) /* IRIX, Solaris <= 9 32-bit */
/* For a valid error number, the system's strerror() function returns
a pointer to a not copied string, not to a buffer. */
if (errnum >= 0 && errnum < sys_nerr)
{
char *errmsg = strerror (errnum);
if (errmsg == NULL || *errmsg == '\0')
ret = EINVAL;
else
ret = safe_copy (buf, buflen, errmsg);
}
else
ret = EINVAL;
# else
gl_lock_lock (strerror_lock);
{
char *errmsg = strerror (errnum);
/* For invalid error numbers, strerror() on
- IRIX 6.5 returns NULL,
- HP-UX 11 returns an empty string. */
if (errmsg == NULL || *errmsg == '\0')
ret = EINVAL;
else
ret = safe_copy (buf, buflen, errmsg);
}
gl_lock_unlock (strerror_lock);
# endif
#endif
#if (defined _WIN32 || defined __WIN32__) && !defined __CYGWIN__
/* MSVC 14 defines names for many error codes in the range 100..140,
but _sys_errlist contains strings only for the error codes
< _sys_nerr = 43. */
if (ret == EINVAL)
{
const char *errmsg;
switch (errnum)
{
case 100 /* EADDRINUSE */:
errmsg = "Address already in use";
break;
case 101 /* EADDRNOTAVAIL */:
errmsg = "Cannot assign requested address";
break;
case 102 /* EAFNOSUPPORT */:
errmsg = "Address family not supported by protocol";
break;
case 103 /* EALREADY */:
errmsg = "Operation already in progress";
break;
case 105 /* ECANCELED */:
errmsg = "Operation canceled";
break;
case 106 /* ECONNABORTED */:
errmsg = "Software caused connection abort";
break;
case 107 /* ECONNREFUSED */:
errmsg = "Connection refused";
break;
case 108 /* ECONNRESET */:
errmsg = "Connection reset by peer";
break;
case 109 /* EDESTADDRREQ */:
errmsg = "Destination address required";
break;
case 110 /* EHOSTUNREACH */:
errmsg = "No route to host";
break;
case 112 /* EINPROGRESS */:
errmsg = "Operation now in progress";
break;
case 113 /* EISCONN */:
errmsg = "Transport endpoint is already connected";
break;
case 114 /* ELOOP */:
errmsg = "Too many levels of symbolic links";
break;
case 115 /* EMSGSIZE */:
errmsg = "Message too long";
break;
case 116 /* ENETDOWN */:
errmsg = "Network is down";
break;
case 117 /* ENETRESET */:
errmsg = "Network dropped connection on reset";
break;
case 118 /* ENETUNREACH */:
errmsg = "Network is unreachable";
break;
case 119 /* ENOBUFS */:
errmsg = "No buffer space available";
break;
case 123 /* ENOPROTOOPT */:
errmsg = "Protocol not available";
break;
case 126 /* ENOTCONN */:
errmsg = "Transport endpoint is not connected";
break;
case 128 /* ENOTSOCK */:
errmsg = "Socket operation on non-socket";
break;
case 129 /* ENOTSUP */:
errmsg = "Not supported";
break;
case 130 /* EOPNOTSUPP */:
errmsg = "Operation not supported";
break;
case 132 /* EOVERFLOW */:
errmsg = "Value too large for defined data type";
break;
case 133 /* EOWNERDEAD */:
errmsg = "Owner died";
break;
case 134 /* EPROTO */:
errmsg = "Protocol error";
break;
case 135 /* EPROTONOSUPPORT */:
errmsg = "Protocol not supported";
break;
case 136 /* EPROTOTYPE */:
errmsg = "Protocol wrong type for socket";
break;
case 138 /* ETIMEDOUT */:
errmsg = "Connection timed out";
break;
case 140 /* EWOULDBLOCK */:
errmsg = "Operation would block";
break;
default:
errmsg = NULL;
break;
}
if (errmsg != NULL)
ret = safe_copy (buf, buflen, errmsg);
}
#endif
if (ret == EINVAL && !*buf)
snprintf (buf, buflen, "Unknown error %d", errnum);
errno = saved_errno;
return ret;
}
}