Merge branch 'clean-up bpftool from legacy support'

Sahid Orentino Ferdjaoui says:

====================

As part of commit 93b8952d223a ("libbpf: deprecate legacy BPF map
definitions") and commit bd054102a8c7 ("libbpf: enforce strict libbpf
1.0 behaviors") The --legacy option is not relevant anymore. #1 is
removing it. #4 is cleaning the code from using libbpf_get_error().

About patches #2 and #3 They are changes discovered while working on
this series (credits to Quentin Monnet). #2 is cleaning-up usage of an
unnecessary PTR_ERR(NULL), finally #3 is fixing an invalid value
passed to strerror().

v1 -> v2:
   - Addressed review comments from Yonghong Song on patch #4
   - Added a patch #5 that removes unwanted function noticed by
     Yonghong Song
v2 -> v3
   - Addressed review comments from Andrii Nakryiko on patch #2, #3, #4
     * clean-up usage of libbpf_get_error() (#2, #3)
     * fix possible return of an uninitialized local variable err
     * fix returned errors using errno
v3 -> v4
   - Addressed review comments from Quentin Monnet
     * fix line moved from patch #2 to patch #3
     * fix missing returned errors using errno
     * fix some returned values to errno instead of -1
====================

Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 6 insertions, 4 deletions

diff --git a/tools/bpf/bpftool/iter.c b/tools/bpf/bpftool/iter.c
index a3e6b167153d..9a1d2365a297 100644
--- a/tools/bpf/bpftool/iter.c
+++ b/tools/bpf/bpftool/iter.c
@@ -4,6 +4,7 @@
 #ifndef _GNU_SOURCE
 #define _GNU_SOURCE
 #endif
+#include <errno.h>
 #include <unistd.h>
 #include <linux/err.h>
 #include <bpf/libbpf.h>
@@ -48,8 +49,8 @@ static int do_pin(int argc, char **argv)
 	}
 
 	obj = bpf_object__open(objfile);
-	err = libbpf_get_error(obj);
-	if (err) {
+	if (!obj) {
+		err = -errno;
 		p_err("can't open objfile %s", objfile);
 		goto close_map_fd;
 	}
@@ -62,13 +63,14 @@ static int do_pin(int argc, char **argv)
 
 	prog = bpf_object__next_program(obj, NULL);
 	if (!prog) {
+		err = -errno;
 		p_err("can't find bpf program in objfile %s", objfile);
 		goto close_obj;
 	}
 
 	link = bpf_program__attach_iter(prog, &iter_opts);
-	err = libbpf_get_error(link);
-	if (err) {
+	if (!link) {
+		err = -errno;
 		p_err("attach_iter failed for program %s",
 		      bpf_program__name(prog));
 		goto close_obj;