bpf: Fix confusing panic() message

When using a filter with netsniff-ng without libpcap support, e.g.

  $ netsniff-ng --in eth0 tcp or udp

we get the error:

  Cannot compile filter tcp or udp

which isn't correct and might be confusing for the user as the intention
wasn't to specify a filter file but a filter string. Correct the error
message accordingly.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>

2 files changed, 2 insertions, 2 deletions

diff --git a/bpf.h b/bpf.h
index bbd05c1..3b0fef5 100644
--- a/bpf.h
+++ b/bpf.h
@@ -27,7 +27,7 @@ static inline void bpf_try_compile(const char *rulefile,
 				   struct sock_fprog *bpf __maybe_unused,
 				   uint32_t link_type __maybe_unused)
 {
-	panic("Cannot open file %s!\n", rulefile);
+	panic("No libpcap support, cannot compile filter: %s\n", rulefile);
 }
 #endif
 static inline void bpf_release(struct sock_fprog *bpf)
diff --git a/bpf_comp.c b/bpf_comp.c
index 3434daf..eca2507 100644
--- a/bpf_comp.c
+++ b/bpf_comp.c
@@ -21,7 +21,7 @@ void bpf_try_compile(const char *rulefile, struct sock_fprog *bpf, uint32_t link
 
 	ret = pcap_compile_nopcap(65535, link_type, &_bpf, rulefile, 1, 0xffffffff);
 	if (ret < 0)
-		panic("Cannot compile filter %s\n", rulefile);
+		panic("Cannot compile filter: %s\n", rulefile);
 
 	bpf->len = _bpf.bf_len;
 	bpf->filter = xrealloc(bpf->filter, bpf->len * sizeof(*out));