c: add dht_infohash_from_hex_null

c/opendht.cpp

@@ -76,7 +76,11 @@ bool dht_infohash_is_zero(const dht_infohash* h) {
 }
 
 void dht_infohash_from_hex(dht_infohash* h, const char* dat) {
-    *h = dht_infohash_to_c(dht::InfoHash(std::string(dat, HASH_LEN*2)));
+    *h = dht_infohash_to_c(dht::InfoHash(std::string_view(dat, HASH_LEN*2)));
+}
+
+void dht_infohash_from_hex_null(dht_infohash* h, const char* dat) {
+    *h = dht_infohash_to_c(dht::InfoHash(std::string_view(dat)));
 }
 
 const char* dht_pkid_print(const dht_pkid* h) {

c/opendht_c.h

@@ -50,6 +50,7 @@ typedef struct dht_infohash dht_infohash;
 OPENDHT_C_PUBLIC void dht_infohash_zero(dht_infohash* h);
 OPENDHT_C_PUBLIC void dht_infohash_random(dht_infohash* h);
 OPENDHT_C_PUBLIC void dht_infohash_from_hex(dht_infohash* h, const char* dat);
+OPENDHT_C_PUBLIC void dht_infohash_from_hex_null(dht_infohash* h, const char* dat);
 OPENDHT_C_PUBLIC void dht_infohash_get(dht_infohash* h, const uint8_t* dat, size_t dat_size);
 OPENDHT_C_PUBLIC void dht_infohash_get_from_string(dht_infohash* h, const char* str);
 OPENDHT_C_PUBLIC const char* dht_infohash_print(const dht_infohash* h);