tools: Introduce str_error_r()

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.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-d4t42fnf48ytlk8rjxs822tf@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/tests/backward-ring-buffer.c b/tools/perf/tests/backward-ring-buffer.c
index e70313f..f20ea4c 100644
--- a/tools/perf/tests/backward-ring-buffer.c
+++ b/tools/perf/tests/backward-ring-buffer.c
@@ -60,7 +60,7 @@
 	err = perf_evlist__mmap(evlist, mmap_pages, true);
 	if (err < 0) {
 		pr_debug("perf_evlist__mmap: %s\n",
-			 strerror_r(errno, sbuf, sizeof(sbuf)));
+			 str_error_r(errno, sbuf, sizeof(sbuf)));
 		return TEST_FAIL;
 	}
 
@@ -124,7 +124,7 @@
 	err = perf_evlist__open(evlist);
 	if (err < 0) {
 		pr_debug("perf_evlist__open: %s\n",
-			 strerror_r(errno, sbuf, sizeof(sbuf)));
+			 str_error_r(errno, sbuf, sizeof(sbuf)));
 		goto out_delete_evlist;
 	}
 
diff --git a/tools/perf/tests/bpf.c b/tools/perf/tests/bpf.c
index f31eed3..da0d87613 100644
--- a/tools/perf/tests/bpf.c
+++ b/tools/perf/tests/bpf.c
@@ -143,14 +143,14 @@
 	err = perf_evlist__open(evlist);
 	if (err < 0) {
 		pr_debug("perf_evlist__open: %s\n",
-			 strerror_r(errno, sbuf, sizeof(sbuf)));
+			 str_error_r(errno, sbuf, sizeof(sbuf)));
 		goto out_delete_evlist;
 	}
 
 	err = perf_evlist__mmap(evlist, opts.mmap_pages, false);
 	if (err < 0) {
 		pr_debug("perf_evlist__mmap: %s\n",
-			 strerror_r(errno, sbuf, sizeof(sbuf)));
+			 str_error_r(errno, sbuf, sizeof(sbuf)));
 		goto out_delete_evlist;
 	}
 
diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
index 07c14e9..c23cbf7 100644
--- a/tools/perf/tests/builtin-test.c
+++ b/tools/perf/tests/builtin-test.c
@@ -258,7 +258,7 @@
 
 	if (child < 0) {
 		pr_err("failed to fork test: %s\n",
-			strerror_r(errno, sbuf, sizeof(sbuf)));
+			str_error_r(errno, sbuf, sizeof(sbuf)));
 		return -1;
 	}
 
diff --git a/tools/perf/tests/event-times.c b/tools/perf/tests/event-times.c
index 9f5698a..19ef77b 100644
--- a/tools/perf/tests/event-times.c
+++ b/tools/perf/tests/event-times.c
@@ -37,7 +37,7 @@
 	err = perf_evlist__open(evlist);
 	if (err < 0) {
 		pr_debug("perf_evlist__open: %s\n",
-			 strerror_r(errno, sbuf, sizeof(sbuf)));
+			 str_error_r(errno, sbuf, sizeof(sbuf)));
 		return err;
 	}
 
diff --git a/tools/perf/tests/mmap-basic.c b/tools/perf/tests/mmap-basic.c
index aea33f5..5c9b931 100644
--- a/tools/perf/tests/mmap-basic.c
+++ b/tools/perf/tests/mmap-basic.c
@@ -49,7 +49,7 @@
 	sched_setaffinity(0, sizeof(cpu_set), &cpu_set);
 	if (sched_setaffinity(0, sizeof(cpu_set), &cpu_set) < 0) {
 		pr_debug("sched_setaffinity() failed on CPU %d: %s ",
-			 cpus->map[0], strerror_r(errno, sbuf, sizeof(sbuf)));
+			 cpus->map[0], str_error_r(errno, sbuf, sizeof(sbuf)));
 		goto out_free_cpus;
 	}
 
@@ -79,7 +79,7 @@
 		if (perf_evsel__open(evsels[i], cpus, threads) < 0) {
 			pr_debug("failed to open counter: %s, "
 				 "tweak /proc/sys/kernel/perf_event_paranoid?\n",
-				 strerror_r(errno, sbuf, sizeof(sbuf)));
+				 str_error_r(errno, sbuf, sizeof(sbuf)));
 			goto out_delete_evlist;
 		}
 
@@ -89,7 +89,7 @@
 
 	if (perf_evlist__mmap(evlist, 128, true) < 0) {
 		pr_debug("failed to mmap events: %d (%s)\n", errno,
-			 strerror_r(errno, sbuf, sizeof(sbuf)));
+			 str_error_r(errno, sbuf, sizeof(sbuf)));
 		goto out_delete_evlist;
 	}
 
diff --git a/tools/perf/tests/openat-syscall-all-cpus.c b/tools/perf/tests/openat-syscall-all-cpus.c
index ad1cb63..265abb1 100644
--- a/tools/perf/tests/openat-syscall-all-cpus.c
+++ b/tools/perf/tests/openat-syscall-all-cpus.c
@@ -41,7 +41,7 @@
 	if (perf_evsel__open(evsel, cpus, threads) < 0) {
 		pr_debug("failed to open counter: %s, "
 			 "tweak /proc/sys/kernel/perf_event_paranoid?\n",
-			 strerror_r(errno, sbuf, sizeof(sbuf)));
+			 str_error_r(errno, sbuf, sizeof(sbuf)));
 		goto out_evsel_delete;
 	}
 
@@ -62,7 +62,7 @@
 		if (sched_setaffinity(0, sizeof(cpu_set), &cpu_set) < 0) {
 			pr_debug("sched_setaffinity() failed on CPU %d: %s ",
 				 cpus->map[cpu],
-				 strerror_r(errno, sbuf, sizeof(sbuf)));
+				 str_error_r(errno, sbuf, sizeof(sbuf)));
 			goto out_close_fd;
 		}
 		for (i = 0; i < ncalls; ++i) {
diff --git a/tools/perf/tests/openat-syscall-tp-fields.c b/tools/perf/tests/openat-syscall-tp-fields.c
index 4344fe4..942dbf4 100644
--- a/tools/perf/tests/openat-syscall-tp-fields.c
+++ b/tools/perf/tests/openat-syscall-tp-fields.c
@@ -51,14 +51,14 @@
 	err = perf_evlist__open(evlist);
 	if (err < 0) {
 		pr_debug("perf_evlist__open: %s\n",
-			 strerror_r(errno, sbuf, sizeof(sbuf)));
+			 str_error_r(errno, sbuf, sizeof(sbuf)));
 		goto out_delete_evlist;
 	}
 
 	err = perf_evlist__mmap(evlist, UINT_MAX, false);
 	if (err < 0) {
 		pr_debug("perf_evlist__mmap: %s\n",
-			 strerror_r(errno, sbuf, sizeof(sbuf)));
+			 str_error_r(errno, sbuf, sizeof(sbuf)));
 		goto out_delete_evlist;
 	}
 
diff --git a/tools/perf/tests/openat-syscall.c b/tools/perf/tests/openat-syscall.c
index 1184f9b..d741412 100644
--- a/tools/perf/tests/openat-syscall.c
+++ b/tools/perf/tests/openat-syscall.c
@@ -29,7 +29,7 @@
 	if (perf_evsel__open_per_thread(evsel, threads) < 0) {
 		pr_debug("failed to open counter: %s, "
 			 "tweak /proc/sys/kernel/perf_event_paranoid?\n",
-			 strerror_r(errno, sbuf, sizeof(sbuf)));
+			 str_error_r(errno, sbuf, sizeof(sbuf)));
 		goto out_evsel_delete;
 	}
 
diff --git a/tools/perf/tests/perf-record.c b/tools/perf/tests/perf-record.c
index b836ee6a..3eb67a9 100644
--- a/tools/perf/tests/perf-record.c
+++ b/tools/perf/tests/perf-record.c
@@ -104,7 +104,7 @@
 	err = sched__get_first_possible_cpu(evlist->workload.pid, &cpu_mask);
 	if (err < 0) {
 		pr_debug("sched__get_first_possible_cpu: %s\n",
-			 strerror_r(errno, sbuf, sizeof(sbuf)));
+			 str_error_r(errno, sbuf, sizeof(sbuf)));
 		goto out_delete_evlist;
 	}
 
@@ -115,7 +115,7 @@
 	 */
 	if (sched_setaffinity(evlist->workload.pid, cpu_mask_size, &cpu_mask) < 0) {
 		pr_debug("sched_setaffinity: %s\n",
-			 strerror_r(errno, sbuf, sizeof(sbuf)));
+			 str_error_r(errno, sbuf, sizeof(sbuf)));
 		goto out_delete_evlist;
 	}
 
@@ -126,7 +126,7 @@
 	err = perf_evlist__open(evlist);
 	if (err < 0) {
 		pr_debug("perf_evlist__open: %s\n",
-			 strerror_r(errno, sbuf, sizeof(sbuf)));
+			 str_error_r(errno, sbuf, sizeof(sbuf)));
 		goto out_delete_evlist;
 	}
 
@@ -138,7 +138,7 @@
 	err = perf_evlist__mmap(evlist, opts.mmap_pages, false);
 	if (err < 0) {
 		pr_debug("perf_evlist__mmap: %s\n",
-			 strerror_r(errno, sbuf, sizeof(sbuf)));
+			 str_error_r(errno, sbuf, sizeof(sbuf)));
 		goto out_delete_evlist;
 	}
 
diff --git a/tools/perf/tests/sw-clock.c b/tools/perf/tests/sw-clock.c
index 36e8ce1..4c9fd04 100644
--- a/tools/perf/tests/sw-clock.c
+++ b/tools/perf/tests/sw-clock.c
@@ -70,7 +70,7 @@
 
 		err = -errno;
 		pr_debug("Couldn't open evlist: %s\nHint: check %s, using %" PRIu64 " in this test.\n",
-			 strerror_r(errno, sbuf, sizeof(sbuf)),
+			 str_error_r(errno, sbuf, sizeof(sbuf)),
 			 knob, (u64)attr.sample_freq);
 		goto out_delete_evlist;
 	}
@@ -78,7 +78,7 @@
 	err = perf_evlist__mmap(evlist, 128, true);
 	if (err < 0) {
 		pr_debug("failed to mmap event: %d (%s)\n", errno,
-			 strerror_r(errno, sbuf, sizeof(sbuf)));
+			 str_error_r(errno, sbuf, sizeof(sbuf)));
 		goto out_delete_evlist;
 	}
 
diff --git a/tools/perf/tests/task-exit.c b/tools/perf/tests/task-exit.c
index 2dfff7a..01a5ba2 100644
--- a/tools/perf/tests/task-exit.c
+++ b/tools/perf/tests/task-exit.c
@@ -91,13 +91,13 @@
 	err = perf_evlist__open(evlist);
 	if (err < 0) {
 		pr_debug("Couldn't open the evlist: %s\n",
-			 strerror_r(-err, sbuf, sizeof(sbuf)));
+			 str_error_r(-err, sbuf, sizeof(sbuf)));
 		goto out_delete_evlist;
 	}
 
 	if (perf_evlist__mmap(evlist, 128, true) < 0) {
 		pr_debug("failed to mmap events: %d (%s)\n", errno,
-			 strerror_r(errno, sbuf, sizeof(sbuf)));
+			 str_error_r(errno, sbuf, sizeof(sbuf)));
 		goto out_delete_evlist;
 	}