add osmo_hexdump_buf() and test

Add osmo_hexdump_buf() as an all-purpose hexdump function, which all other
osmo_hexdump_*() implementations now call. It absorbs the static
_osmo_hexdump(). Add tests for osmo_hexdump_buf().

Rationale: recently during patch review, a situation came up where two hexdumps
in a single printf would have been useful. Now I've faced a similar situation
again, in ongoing development. So I decided it is time to provide this API.

The traditional osmo_hexdump() API returns a non-const char*, which should
probably have been a const instead. Particularly this new function may return a
string constant "" if the buf is NULL or empty, so return const char*. That is
why the older implementations calling osmo_hexdump_buf() separately return the
buffer instead of the const return value directly.

Change-Id: I590595567b218b24e53c9eb1fd8736c0324d371d

1 files changed, 3 insertions, 0 deletions

diff --git a/include/osmocom/core/utils.h b/include/osmocom/core/utils.h
index 987080e2..fe360b33 100644
--- a/include/osmocom/core/utils.h
+++ b/include/osmocom/core/utils.h
@@ -56,6 +56,9 @@ int osmo_hexparse(const char *str, uint8_t *b, int max_len);
 char *osmo_ubit_dump(const uint8_t *bits, unsigned int len);
 char *osmo_hexdump(const unsigned char *buf, int len);
 char *osmo_hexdump_nospc(const unsigned char *buf, int len);
+const char *osmo_hexdump_buf(char *out_buf, size_t out_buf_size, const unsigned char *buf, int len, const char *delim,
+			     bool delim_after_last);
+
 char *osmo_osmo_hexdump_nospc(const unsigned char *buf, int len) __attribute__((__deprecated__));
 
 #define osmo_static_assert(exp, name) typedef int dummy##name [(exp) ? 1 : -1] __attribute__((__unused__));