Merge branch 'Prepare veristat for packaging'

Andrii Nakryiko says:

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

This patch set relicenses veristat.c to dual GPL-2.0/BSD-2 license and
prepares it to be mirrored to Github at libbpf/veristat repo.

Few small issues in the source code are fixed, found during Github sync
preparetion.

v2->v3:
  - fix few warnings about uninitialized variable uses;
v1->v2:
  - drop linux/compiler.h and define own ARRAY_SIZE macro;
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>

tools/testing/selftests/bpf/veristat.c

@@ -1,10 +1,9 @@
-// SPDX-License-Identifier: GPL-2.0
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
 /* Copyright (c) 2022 Meta Platforms, Inc. and affiliates. */
 #define _GNU_SOURCE
 #include <argp.h>
 #include <string.h>
 #include <stdlib.h>
-#include <linux/compiler.h>
 #include <sched.h>
 #include <pthread.h>
 #include <dirent.h>
@@ -20,6 +19,10 @@
 #include <gelf.h>
 #include <float.h>
 
+#ifndef ARRAY_SIZE
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
+#endif
+
 enum stat_id {
 	VERDICT,
 	DURATION,
@@ -140,6 +143,7 @@ static struct env {
 	bool quiet;
 	int log_level;
 	enum resfmt out_fmt;
+	bool show_version;
 	bool comparison_mode;
 	bool replay_mode;
 
@@ -176,16 +180,22 @@ static int libbpf_print_fn(enum libbpf_print_level level, const char *format, va
 	return vfprintf(stderr, format, args);
 }
 
-const char *argp_program_version = "veristat";
+#ifndef VERISTAT_VERSION
+#define VERISTAT_VERSION "<kernel>"
+#endif
+
+const char *argp_program_version = "veristat v" VERISTAT_VERSION;
 const char *argp_program_bug_address = "<bpf@vger.kernel.org>";
 const char argp_program_doc[] =
 "veristat    BPF verifier stats collection and comparison tool.\n"
 "\n"
 "USAGE: veristat <obj-file> [<obj-file>...]\n"
-"   OR: veristat -C <baseline.csv> <comparison.csv>\n";
+"   OR: veristat -C <baseline.csv> <comparison.csv>\n"
+"   OR: veristat -R <results.csv>\n";
 
 static const struct argp_option opts[] = {
 	{ NULL, 'h', NULL, OPTION_HIDDEN, "Show the full help" },
+	{ "version", 'V', NULL, 0, "Print version" },
 	{ "verbose", 'v', NULL, 0, "Verbose mode" },
 	{ "log-level", 'l', "LEVEL", 0, "Verifier log level (default 0 for normal mode, 1 for verbose mode)" },
 	{ "debug", 'd', NULL, 0, "Debug mode (turns on libbpf debug logging)" },
@@ -212,6 +222,9 @@ static error_t parse_arg(int key, char *arg, struct argp_state *state)
 	case 'h':
 		argp_state_help(state, stderr, ARGP_HELP_STD_HELP);
 		break;
+	case 'V':
+		env.show_version = true;
+		break;
 	case 'v':
 		env.verbose = true;
 		break;
@@ -797,7 +810,7 @@ static int guess_prog_type_by_ctx_name(const char *ctx_name,
 		enum bpf_prog_type prog_type;
 		enum bpf_attach_type attach_type;
 	} ctx_map[] = {
-		/* __sk_buff is most ambiguous, for now we assume cgroup_skb */
+		/* __sk_buff is most ambiguous, we assume TC program */
 		{ "__sk_buff", "sk_buff", BPF_PROG_TYPE_SCHED_CLS },
 		{ "bpf_sock", "sock", BPF_PROG_TYPE_CGROUP_SOCK, BPF_CGROUP_INET4_POST_BIND },
 		{ "bpf_sock_addr", "bpf_sock_addr_kern",  BPF_PROG_TYPE_CGROUP_SOCK_ADDR, BPF_CGROUP_INET4_BIND },
@@ -1032,6 +1045,7 @@ static int process_obj(const char *filename)
 			goto cleanup;
 		}
 
+		lprog = NULL;
 		bpf_object__for_each_program(tprog, tobj) {
 			const char *tprog_name = bpf_program__name(tprog);
 
@@ -1842,6 +1856,7 @@ static int handle_comparison_mode(void)
 one_more_time:
 	output_comp_headers(cur_fmt);
 
+	last_idx = -1;
 	for (i = 0; i < env.join_stat_cnt; i++) {
 		const struct verif_stats_join *join = &env.join_stats[i];
 
@@ -1991,6 +2006,11 @@ int main(int argc, char **argv)
 	if (argp_parse(&argp, argc, argv, 0, NULL, NULL))
 		return 1;
 
+	if (env.show_version) {
+		printf("%s\n", argp_program_version);
+		return 0;
+	}
+
 	if (env.verbose && env.quiet) {
 		fprintf(stderr, "Verbose and quiet modes are incompatible, please specify just one or neither!\n\n");
 		argp_help(&argp, stderr, ARGP_HELP_USAGE, "veristat");