cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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tep_strerror.c (1396B)


      1// SPDX-License-Identifier: LGPL-2.1
      2#undef _GNU_SOURCE
      3#include <string.h>
      4#include <stdio.h>
      5
      6#include "event-parse.h"
      7
      8#undef _PE
      9#define _PE(code, str) str
     10static const char * const tep_error_str[] = {
     11	TEP_ERRORS
     12};
     13#undef _PE
     14
     15/*
     16 * The tools so far have been using the strerror_r() GNU variant, that returns
     17 * a string, be it the buffer passed or something else.
     18 *
     19 * But that, besides being tricky in cases where we expect that the function
     20 * using strerror_r() returns the error formatted in a provided buffer (we have
     21 * to check if it returned something else and copy that instead), breaks the
     22 * build on systems not using glibc, like Alpine Linux, where musl libc is
     23 * used.
     24 *
     25 * So, introduce yet another wrapper, str_error_r(), that has the GNU
     26 * interface, but uses the portable XSI variant of strerror_r(), so that users
     27 * rest asured that the provided buffer is used and it is what is returned.
     28 */
     29int tep_strerror(struct tep_handle *tep __maybe_unused,
     30		 enum tep_errno errnum, char *buf, size_t buflen)
     31{
     32	const char *msg;
     33	int idx;
     34
     35	if (!buflen)
     36		return 0;
     37
     38	if (errnum >= 0) {
     39		int err = strerror_r(errnum, buf, buflen);
     40		buf[buflen - 1] = 0;
     41		return err;
     42	}
     43
     44	if (errnum <= __TEP_ERRNO__START ||
     45	    errnum >= __TEP_ERRNO__END)
     46		return -1;
     47
     48	idx = errnum - __TEP_ERRNO__START - 1;
     49	msg = tep_error_str[idx];
     50	snprintf(buf, buflen, "%s", msg);
     51
     52	return 0;
     53}