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// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
/* Copyright (c) 2020 Facebook */
#include <stdio.h>
#include <unistd.h>
#include <sys/resource.h>
#include <bpf/libbpf.h>
#include "minimal.skel.h"
static int libbpf_print_fn(enum libbpf_print_level level, const char *format, va_list args)
{
return vfprintf(stderr, format, args);
}
static void bump_memlock_rlimit(void)
{
struct rlimit rlim_new = {
.rlim_cur = RLIM_INFINITY,
.rlim_max = RLIM_INFINITY,
};
if (setrlimit(RLIMIT_MEMLOCK, &rlim_new)) {
fprintf(stderr, "Failed to increase RLIMIT_MEMLOCK limit!\n");
exit(1);
}
}
int main(int argc, char **argv)
{
struct minimal_bpf *skel;
int err;
/* Set up libbpf errors and debug info callback */
libbpf_set_print(libbpf_print_fn);
/* Bump RLIMIT_MEMLOCK to allow BPF sub-system to do anything */
bump_memlock_rlimit();
/* Open BPF application */
skel = minimal_bpf__open();
if (!skel) {
fprintf(stderr, "Failed to open BPF skeleton\n");
return 1;
}
/* ensure BPF program only handles write() syscalls from our process */
skel->bss->my_pid = getpid();
/* Load & verify BPF programs */
err = minimal_bpf__load(skel);
if (err) {
fprintf(stderr, "Failed to load and verify BPF skeleton\n");
goto cleanup;
}
/* Attach tracepoint handler */
err = minimal_bpf__attach(skel);
if (err) {
fprintf(stderr, "Failed to attach BPF skeleton\n");
goto cleanup;
}
printf("Successfully started!\n");
for (;;) {
/* trigger our BPF program */
fprintf(stderr, ".");
sleep(1);
}
cleanup:
minimal_bpf__destroy(skel);
return -err;
}
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