libbpf: remove unused libbpf_strerror_r and STRERR_BUFSIZE

libbpf_strerror_r() is not exposed as public API and neither is it used
inside libbpf itself. Remove it altogether.

Same for STRERR_BUFSIZE, it's just an orphaned leftover constant which
we missed to clean up some time earlier.

Signed-off-by: Andrii Nakryiko <[email protected]>

Author: anakryiko

tools/lib/bpf/libbpf.c

@@ -319,8 +319,6 @@ static void pr_perm_msg(int err)
 		buf);
 }
 
-#define STRERR_BUFSIZE  128
-
 /* Copied from tools/perf/util/util.h */
 #ifndef zfree
 # define zfree(ptr) ({ free(*ptr); *ptr = NULL; })

tools/lib/bpf/str_error.c

@@ -12,30 +12,6 @@
 /* make sure libbpf doesn't use kernel-only integer typedefs */
 #pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
 
-/*
- * Wrapper to allow for building in non-GNU systems such as Alpine Linux's musl
- * libc, while checking strerror_r() return to avoid having to check this in
- * all places calling it.
- */
-char *libbpf_strerror_r(int err, char *dst, int len)
-{
-	int ret = strerror_r(err < 0 ? -err : err, dst, len);
-	/* on glibc <2.13, ret == -1 and errno is set, if strerror_r() can't
-	 * handle the error, on glibc >=2.13 *positive* (errno-like) error
-	 * code is returned directly
-	 */
-	if (ret == -1)
-		ret = errno;
-	if (ret) {
-		if (ret == EINVAL)
-			/* strerror_r() doesn't recognize this specific error */
-			snprintf(dst, len, "unknown error (%d)", err < 0 ? err : -err);
-		else
-			snprintf(dst, len, "ERROR: strerror_r(%d)=%d", err, ret);
-	}
-	return dst;
-}
-
 const char *libbpf_errstr(int err)
 {
 	static __thread char buf[12];

tools/lib/bpf/str_error.h

@@ -2,10 +2,6 @@
 #ifndef __LIBBPF_STR_ERROR_H
 #define __LIBBPF_STR_ERROR_H
 
-#define STRERR_BUFSIZE  128
-
-char *libbpf_strerror_r(int err, char *dst, int len);
-
 /**
  * @brief **libbpf_errstr()** returns string corresponding to numeric errno
  * @param err negative numeric errno