Add missed z_string_* methods

docs/api.rst

@@ -379,6 +379,10 @@ Primitives
 .. autocfunction:: primitives.h::z_sample_loan
 .. autocfunction:: primitives.h::z_string_data
 .. autocfunction:: primitives.h::z_string_len
+.. autocfunction:: primitives.h::z_string_wrap
+.. autocfunction:: primitives.h::z_string_from_substring
+.. autocfunction:: primitives.h::z_string_empty
+.. autocfunction:: primitives.h::z_string_is_empty
 .. autocfunction:: primitives.h::z_scout
 .. autocfunction:: primitives.h::z_open
 .. autocfunction:: primitives.h::z_close

include/zenoh-pico/api/primitives.h

@@ -1133,6 +1133,49 @@ const char *z_string_data(const z_loaned_string_t *str);
  */
 size_t z_string_len(const z_loaned_string_t *str);
 
+/**
+ * Builds a :c:type:`z_string_t` by wrapping a ``const char *`` string.
+ *
+ * Parameters:
+ *   str: Pointer to an uninitialized :c:type:`z_string_t`.
+ *   value: Pointer to a null terminated string.
+ *
+ * Return:
+ *   ``0`` if creation successful, ``negative value`` otherwise.
+ */
+int8_t z_string_wrap(z_owned_string_t *str, const char *value);
+
+/**
+ * Builds an empty :c:type:`z_string_t`.
+ *
+ * Parameters:
+ *   str: Pointer to an uninitialized :c:type:`z_string_t`.
+ */
+void z_string_empty(z_owned_string_t *str);
+
+/**
+ * Builds a :c:type:`z_string_t` by wrapping a substring specified by ``const char *`` and length `len`.
+ *
+ * Parameters:
+ *   value: Pointer to a string.
+ *   len: String size.
+ *   str: Pointer to an uninitialized :c:type:`z_string_t`.
+ *
+ * Return:
+ *   ``0`` if creation successful, ``negative value`` otherwise.
+ */
+int8_t z_string_from_substring(z_owned_string_t *str, const char *value, size_t len);
+
+/**
+ * Checks if string is empty
+ *
+ * Parameters:
+ *   str: Pointer to a :c:type:`z_loaned_string_t` to check.
+ * Return:
+ *  ``true`` if conainer is empty, ``false`` otherwise.
+ */
+bool z_string_is_empty(const z_loaned_string_t *str);
+
 /************* Primitives **************/
 /**
  * Scouts for other Zenoh entities like routers and/or peers.

src/api/api.c

@@ -837,6 +837,24 @@ const z_loaned_encoding_t *z_reply_err_encoding(const z_loaned_reply_err_t *repl
 const char *z_string_data(const z_loaned_string_t *str) { return str->val; }
 size_t z_string_len(const z_loaned_string_t *str) { return str->len; }
 
+int8_t z_string_wrap(z_owned_string_t *str, const char *value) {
+    str->_val = _z_string_wrap((char *)value);
+    return _Z_RES_OK;
+}
+
+void z_string_empty(z_owned_string_t *str) {
+    str->_val.val = NULL;
+    str->_val.len = 0;
+}
+
+int8_t z_string_from_substring(z_owned_string_t *str, const char *value, size_t len) {
+    str->_val.val = (char *)value;
+    str->_val.len = len;
+    return _Z_RES_OK;
+}
+
+bool z_string_is_empty(const z_loaned_string_t *str) { return str->val == NULL; }
+
 #if Z_FEATURE_PUBLICATION == 1
 int8_t _z_undeclare_and_clear_publisher(_z_publisher_t *pub) {
     int8_t ret = _Z_RES_OK;