From 6dc5fb8803613177b3305d3d547bf155778cd83d Mon Sep 17 00:00:00 2001
From: Denis Biryukov <denis.biryukov@zettascale.tech>
Date: Wed, 9 Oct 2024 18:45:12 +0200
Subject: [PATCH] reintroduce z_encoding_equals; fix encoding_from_substr to
 work similarly to zenoh-rust;

---
 src/api/api.c               |  4 ++++
 src/api/encoding.c          | 11 ++++++++---
 tests/z_api_encoding_test.c | 12 ++++++++++++
 3 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/src/api/api.c b/src/api/api.c
index 313649691..727ef0462 100644
--- a/src/api/api.c
+++ b/src/api/api.c
@@ -215,6 +215,10 @@ z_result_t zp_config_insert(z_loaned_config_t *config, uint8_t key, const char *
 _Z_OWNED_FUNCTIONS_VALUE_IMPL(_z_encoding_t, encoding, _z_encoding_check, _z_encoding_null, _z_encoding_copy,
                               _z_encoding_clear)
 
+bool z_encoding_equals(const z_loaned_encoding_t *left, const z_loaned_encoding_t *right) {
+    return left->id == right->id && _z_string_equals(&left->schema, &right->schema);
+}
+
 z_result_t z_slice_copy_from_buf(z_owned_slice_t *slice, const uint8_t *data, size_t len) {
     slice->_val = _z_slice_copy_from_buf(data, len);
     if (slice->_val.start == NULL) {
diff --git a/src/api/encoding.c b/src/api/encoding.c
index 61535811b..8cbe24ae1 100644
--- a/src/api/encoding.c
+++ b/src/api/encoding.c
@@ -157,12 +157,17 @@ static z_result_t _z_encoding_convert_from_substr(z_owned_encoding_t *encoding,
     }
 
     // Check id_end value + corner cases
-    if ((pos != len) && (pos != 0)) {
+    if (pos != 0) {
         uint16_t id = _z_encoding_values_str_to_int(s, pos);
         // Check id
         if (id != UINT16_MAX) {
-            const char *ptr = (pos + 1 == len) ? NULL : s + pos + 1;
-            return _z_encoding_make(&encoding->_val, id, ptr, len - pos - 1);
+            const char *ptr = NULL;
+            size_t remaining = 0;
+            if (pos + 1 < len) {
+                ptr = s + pos + 1;
+                remaining = len - pos - 1;
+            }
+            return _z_encoding_make(&encoding->_val, id, ptr, remaining);
         }
     }
     // By default store the string as schema
diff --git a/tests/z_api_encoding_test.c b/tests/z_api_encoding_test.c
index 8f3577085..7565c48dd 100644
--- a/tests/z_api_encoding_test.c
+++ b/tests/z_api_encoding_test.c
@@ -4,6 +4,7 @@
 
 #include "zenoh-pico/api/primitives.h"
 #include "zenoh-pico/api/types.h"
+#include "zenoh-pico/api/encoding.h"
 
 #undef NDEBUG
 #include <assert.h>
@@ -94,9 +95,20 @@ void test_with_schema(void) {
     z_string_drop(z_string_move(&s));
 }
 
+void test_equals(void) {
+#if Z_FEATURE_ENCODING_VALUES == 1
+    z_owned_encoding_t e;
+    z_encoding_from_str(&e, "zenoh/string");
+    assert(z_encoding_equals(z_encoding_loan(&e), z_encoding_zenoh_string()));
+    assert(!z_encoding_equals(z_encoding_loan(&e), z_encoding_zenoh_serialized()));
+    z_encoding_drop(z_encoding_move(&e));
+#endif
+}
+
 int main(void) {
     test_null_encoding();
     test_encoding_without_id();
     test_encoding_with_id();
     test_with_schema();
+    test_equals();
 }