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/* This file excercises the ELF loader. It is not a valid BPF program. */
#include "common.h"
int __section("socket/tail") tail_1() {
return 42;
}
// Tail call map (program array) initialized with program pointers.
struct {
__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
__type(key, uint32_t);
__type(value, uint32_t);
__uint(max_entries, 2);
__array(values, int());
} prog_array_init __section(".maps") = {
.values =
{
// Skip index 0 to exercise empty array slots.
[1] = &tail_1,
},
};
int __section("socket/main") tail_main(void *ctx) {
// If prog_array_init is correctly populated, the tail call
// will succeed and the program will continue in tail_1 and
// not return here.
bpf_tail_call(ctx, &prog_array_init, 1);
return 0;
}
// Inner map with a single possible entry.
struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__uint(max_entries, 1);
__type(key, uint32_t);
__type(value, uint32_t);
} inner_map __section(".maps");
// Outer map carrying a reference to the inner map.
struct {
__uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS);
__uint(max_entries, 2);
__type(key, uint32_t);
__type(value, uint32_t);
__array(values, typeof(inner_map));
} outer_map_init __section(".maps") = {
.values =
{
// Skip index 0 to exercise empty array slots.
[1] = &inner_map,
},
};
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