[PATCH] bpf: program printed in bpf_debug compatible format

[Chen Jingpiao]

On Wed, Jun 6, 2018 at 2:35 AM Elazar Leibovich <elazarl at gmail.com> wrote:

$ git apply 0001-bpf-program-printed-in-bpf_debug-compatible-format.patch

0001-bpf-program-printed-in-bpf_debug-compatible-format.patch:10: trailing
whitespace.
int i;
0001-bpf-program-printed-in-bpf_debug-compatible-format.patch:11: trailing
whitespace.
int n = MIN(len, BPF_MAXINSNS);
0001-bpf-program-printed-in-bpf_debug-compatible-format.patch:12: trailing
whitespace.
tprintf("%hu", n); // bpf_debug requires <len>, prefix
0001-bpf-program-printed-in-bpf_debug-compatible-format.patch:13: trailing
whitespace.
for (i=0; i<n; i++) {
0001-bpf-program-printed-in-bpf_debug-compatible-format.patch:14: trailing
whitespace.
struct bpf_filter_block filter;
0001-bpf-program-printed-in-bpf_debug-compatible-format.patch:15: trailing
whitespace.
tfetch_mem(tcp, addr + i*sizeof(filter),
0001-bpf-program-printed-in-bpf_debug-compatible-format.patch:16: trailing
whitespace.
sizeof(filter), &filter);
0001-bpf-program-printed-in-bpf_debug-compatible-format.patch:17: trailing
whitespace.
tprintf(",%u %u %u %u", filter.code, filter.jt,
0001-bpf-program-printed-in-bpf_debug-compatible-format.patch:18: trailing
whitespace.
filter.jf, filter.k);
0001-bpf-program-printed-in-bpf_debug-compatible-format.patch:19: trailing
whitespace.
}
0001-bpf-program-printed-in-bpf_debug-compatible-format.patch:20: trailing
whitespace.
if (n < len)
0001-bpf-program-printed-in-bpf_debug-compatible-format.patch:21: trailing
whitespace.
tprints("...");
fatal: 12 lines add whitespace errors.

please update the patch and read guide for new contributors [1].

> diff --git a/bpf_filter.c b/bpf_filter.c
> index a102e14..97f202b 100644
> --- a/bpf_filter.c
> +++ b/bpf_filter.c
> @@ -177,7 +177,18 @@ print_bpf_fprog(struct tcb *const tcp, const
kernel_ulong_t addr,
>  const unsigned short len, const print_bpf_filter_fn print_k)
>  {
>  if (abbrev(tcp)) {
> - printaddr(addr);
> + int i;
> + int n = MIN(len, BPF_MAXINSNS);
> + tprintf("%hu", n); // bpf_debug requires <len>, prefix

Why you use %hu print int variable?

> + for (i=0; i<n; i++) {
> + struct bpf_filter_block filter;
> + tfetch_mem(tcp, addr + i*sizeof(filter),
> + sizeof(filter), &filter);
> + tprintf(",%u %u %u %u", filter.code, filter.jt,
> + filter.jf, filter.k);
> + }
> + if (n < len)
> + tprints("...");

We can call the print_array to do the same thing.  Why you want to print in
this
raw format?

>  } else {
>  struct bpf_filter_block_data fbd = { .fn = print_k };
>  struct bpf_filter_block filter;
>

[1] https://strace.io/wiki/NewContributorGuide
--
Chen Jingpiao
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