diff options
Diffstat (limited to 'gl/strerror.c')
-rw-r--r-- | gl/strerror.c | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/gl/strerror.c b/gl/strerror.c new file mode 100644 index 0000000000..54e3a140be --- /dev/null +++ b/gl/strerror.c @@ -0,0 +1,70 @@ +/* strerror.c --- POSIX compatible system error routine + + Copyright (C) 2007-2013 Free Software Foundation, Inc. + + This program 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 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 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 <http://www.gnu.org/licenses/>. */ + +#include <config.h> + +/* Specification. */ +#include <string.h> + +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "intprops.h" +#include "strerror-override.h" +#include "verify.h" + +/* Use the system functions, not the gnulib overrides in this file. */ +#undef sprintf + +char * +strerror (int n) +#undef strerror +{ + static char buf[STACKBUF_LEN]; + size_t len; + + /* Cast away const, due to the historical signature of strerror; + callers should not be modifying the string. */ + const char *msg = strerror_override (n); + if (msg) + return (char *) msg; + + msg = strerror (n); + + /* Our strerror_r implementation might use the system's strerror + buffer, so all other clients of strerror have to see the error + copied into a buffer that we manage. This is not thread-safe, + even if the system strerror is, but portable programs shouldn't + be using strerror if they care about thread-safety. */ + if (!msg || !*msg) + { + static char const fmt[] = "Unknown error %d"; + verify (sizeof buf >= sizeof (fmt) + INT_STRLEN_BOUND (n)); + sprintf (buf, fmt, n); + errno = EINVAL; + return buf; + } + + /* Fix STACKBUF_LEN if this ever aborts. */ + len = strlen (msg); + if (sizeof buf <= len) + abort (); + + return memcpy (buf, msg, len + 1); +} |