linux-sg2042/tools/lib/traceevent/tep_strerror.c

54 lines
1.4 KiB
C

// SPDX-License-Identifier: LGPL-2.1
#undef _GNU_SOURCE
#include <string.h>
#include <stdio.h>
#include "event-parse.h"
#undef _PE
#define _PE(code, str) str
static const char * const tep_error_str[] = {
TEP_ERRORS
};
#undef _PE
/*
* 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.
*/
int tep_strerror(struct tep_handle *tep __maybe_unused,
enum tep_errno errnum, char *buf, size_t buflen)
{
const char *msg;
int idx;
if (!buflen)
return 0;
if (errnum >= 0) {
int err = strerror_r(errnum, buf, buflen);
buf[buflen - 1] = 0;
return err;
}
if (errnum <= __TEP_ERRNO__START ||
errnum >= __TEP_ERRNO__END)
return -1;
idx = errnum - __TEP_ERRNO__START - 1;
msg = tep_error_str[idx];
snprintf(buf, buflen, "%s", msg);
return 0;
}