cbsp: Introduce osmo_cbsp_errstr

Rather than having the encoder/decoder library print some log
messages in case of encoding/decoding errors, let's provide something
akin to 'errno', but with a string instead of a numeric error code.

The 'osmo_cbsp_errstr' global variable (if set) contains a
human-readable string describing the most recent encoding/decoding error.

It exists separately for each thread and hence can be used safely in
multi-threaded environments.

Change-Id: Id9a5a595a76ba278647aee9470ded213d8464103

1 files changed, 2 insertions, 0 deletions

diff --git a/include/osmocom/gsm/cbsp.h b/include/osmocom/gsm/cbsp.h
index d47b37bb..90516cb7 100644
--- a/include/osmocom/gsm/cbsp.h
+++ b/include/osmocom/gsm/cbsp.h
@@ -283,6 +283,8 @@ struct osmo_cbsp_decoded {
 	} u;
 };
 
+extern const __thread char *osmo_cbsp_errstr;
+
 struct msgb *osmo_cbsp_msgb_alloc(void *ctx, const char *name);
 struct msgb *osmo_cbsp_encode(void *ctx, const struct osmo_cbsp_decoded *in);
 struct osmo_cbsp_decoded *osmo_cbsp_decode(void *ctx, struct msgb *in);