diff --git a/lib/sdp.c b/lib/sdp.c
index 4b10d8f..dfc06b6 100644
--- a/lib/sdp.c
+++ b/lib/sdp.c
@@ -2180,16 +2180,21 @@ int sdp_get_int_attr(const sdp_record_t *rec, uint16_t attrid, int *value)
 }
 
 int sdp_get_string_attr(const sdp_record_t *rec, uint16_t attrid, char *value,
-								int valuelen)
+								size_t valuelen)
 {
 	sdp_data_t *sdpdata = sdp_data_get(rec, attrid);
-	if (sdpdata)
-		/* Verify that it is what the caller expects */
-		if (SDP_IS_TEXT_STR(sdpdata->dtd))
-			if ((int) strlen(sdpdata->val.str) < valuelen) {
-				strcpy(value, sdpdata->val.str);
-				return 0;
-			}
+
+	/* Verify that it is what the caller expects */
+	if (!sdpdata || !SDP_IS_TEXT_STR(sdpdata->dtd))
+		goto fail;
+
+	/* Have to copy the NULL terminator too, so check len < valuelen. */
+	if (strlen(sdpdata->val.str) < valuelen) {
+		strcpy(value, sdpdata->val.str);
+		return 0;
+	}
+
+fail:
 	errno = EINVAL;
 	return -1;
 }
diff --git a/lib/sdp_lib.h b/lib/sdp_lib.h
index 22776b6..aad664f 100644
--- a/lib/sdp_lib.h
+++ b/lib/sdp_lib.h
@@ -141,7 +141,8 @@ int sdp_general_inquiry(inquiry_info *ii, int dev_num, int duration, uint8_t *fo
 
 /* flexible extraction of basic attributes - Jean II */
 int sdp_get_int_attr(const sdp_record_t *rec, uint16_t attr, int *value);
-int sdp_get_string_attr(const sdp_record_t *rec, uint16_t attr, char *value, int valuelen);
+int sdp_get_string_attr(const sdp_record_t *rec, uint16_t attr, char *value,
+							size_t valuelen);
 
 /*
  * Basic sdp data functions
@@ -543,32 +544,38 @@ int sdp_get_service_avail(const sdp_record_t *rec, uint8_t *svcAvail);
 int sdp_get_service_ttl(const sdp_record_t *rec, uint32_t *svcTTLInfo);
 int sdp_get_database_state(const sdp_record_t *rec, uint32_t *svcDBState);
 
-static inline int sdp_get_service_name(const sdp_record_t *rec, char *str, int len)
+static inline int sdp_get_service_name(const sdp_record_t *rec, char *str,
+								size_t len)
 {
 	return sdp_get_string_attr(rec, SDP_ATTR_SVCNAME_PRIMARY, str, len);
 }
 
-static inline int sdp_get_service_desc(const sdp_record_t *rec, char *str, int len)
+static inline int sdp_get_service_desc(const sdp_record_t *rec, char *str,
+								size_t len)
 {
 	return sdp_get_string_attr(rec, SDP_ATTR_SVCDESC_PRIMARY, str, len);
 }
 
-static inline int sdp_get_provider_name(const sdp_record_t *rec, char *str, int len)
+static inline int sdp_get_provider_name(const sdp_record_t *rec, char *str,
+								size_t len)
 {
 	return sdp_get_string_attr(rec, SDP_ATTR_PROVNAME_PRIMARY, str, len);
 }
 
-static inline int sdp_get_doc_url(const sdp_record_t *rec, char *str, int len)
+static inline int sdp_get_doc_url(const sdp_record_t *rec, char *str,
+								size_t len)
 {
 	return sdp_get_string_attr(rec, SDP_ATTR_DOC_URL, str, len);
 }
 
-static inline int sdp_get_clnt_exec_url(const sdp_record_t *rec, char *str, int len)
+static inline int sdp_get_clnt_exec_url(const sdp_record_t *rec, char *str,
+								size_t len)
 {
 	return sdp_get_string_attr(rec, SDP_ATTR_CLNT_EXEC_URL, str, len);
 }
 
-static inline int sdp_get_icon_url(const sdp_record_t *rec, char *str, int len)
+static inline int sdp_get_icon_url(const sdp_record_t *rec, char *str,
+								size_t len)
 {
 	return sdp_get_string_attr(rec, SDP_ATTR_ICON_URL, str, len);
 }