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// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2021 Google LLC. */
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
__u32 pid = 0;
char num_out[64] = {};
long num_ret = 0;
char ip_out[64] = {};
long ip_ret = 0;
char sym_out[64] = {};
long sym_ret = 0;
char addr_out[64] = {};
long addr_ret = 0;
char str_out[64] = {};
long str_ret = 0;
char over_out[6] = {};
long over_ret = 0;
char pad_out[10] = {};
long pad_ret = 0;
char noarg_out[64] = {};
long noarg_ret = 0;
long nobuf_ret = 0;
extern const void schedule __ksym;
SEC("raw_tp/sys_enter")
int handler(const void *ctx)
{
/* Convenient values to pretty-print */
const __u8 ex_ipv4[] = {127, 0, 0, 1};
const __u8 ex_ipv6[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1};
static const char str1[] = "str1";
static const char longstr[] = "longstr";
if ((int)bpf_get_current_pid_tgid() != pid)
return 0;
/* Integer types */
num_ret = BPF_SNPRINTF(num_out, sizeof(num_out),
"%d %u %x %li %llu %lX",
-8, 9, 150, -424242, 1337, 0xDABBAD00);
/* IP addresses */
ip_ret = BPF_SNPRINTF(ip_out, sizeof(ip_out), "%pi4 %pI6",
&ex_ipv4, &ex_ipv6);
/* Symbol lookup formatting */
sym_ret = BPF_SNPRINTF(sym_out, sizeof(sym_out), "%ps %pS %pB",
&schedule, &schedule, &schedule);
/* Kernel pointers */
addr_ret = BPF_SNPRINTF(addr_out, sizeof(addr_out), "%pK %px %p",
0, 0xFFFF00000ADD4E55, 0xFFFF00000ADD4E55);
/* Strings embedding */
str_ret = BPF_SNPRINTF(str_out, sizeof(str_out), "%s %+05s",
str1, longstr);
/* Overflow */
over_ret = BPF_SNPRINTF(over_out, sizeof(over_out), "%%overflow");
/* Padding of fixed width numbers */
pad_ret = BPF_SNPRINTF(pad_out, sizeof(pad_out), "%5d %0900000X", 4, 4);
/* No args */
noarg_ret = BPF_SNPRINTF(noarg_out, sizeof(noarg_out), "simple case");
/* No buffer */
nobuf_ret = BPF_SNPRINTF(NULL, 0, "only interested in length %d", 60);
return 0;
}
char _license[] SEC("license") = "GPL";
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