linux/tools/lib/str_error_r.c

28 lines
1.0 KiB
C

// SPDX-License-Identifier: GPL-2.0
#undef _GNU_SOURCE
#include <string.h>
#include <stdio.h>
#include <linux/string.h>
/*
* The tools so far have been using the strerror_r() GNU variant, that returns
* a string, be it the buffer passed or something else.
*
* But that, besides being tricky in cases where we expect that the function
* using strerror_r() returns the error formatted in a provided buffer (we have
* to check if it returned something else and copy that instead), breaks the
* build on systems not using glibc, like Alpine Linux, where musl libc is
* used.
*
* So, introduce yet another wrapper, str_error_r(), that has the GNU
* interface, but uses the portable XSI variant of strerror_r(), so that users
* rest asured that the provided buffer is used and it is what is returned.
*/
char *str_error_r(int errnum, char *buf, size_t buflen)
{
int err = strerror_r(errnum, buf, buflen);
if (err)
snprintf(buf, buflen, "INTERNAL ERROR: strerror_r(%d, %p, %zd)=%d", errnum, buf, buflen, err);
return buf;
}