return required length if the given buffer is too small

RaphiaRa · Feb 11, 2025 · 9582245 · 9582245
1 parent b963c93
commit 9582245
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/spms.c b/spms.c
@@ -722,8 +722,10 @@ spms_err spms_sub_read_msg(spms_sub *ring, void *addr, size_t *len, struct spms_
         spms_err ret = spms_sub_get_read_buf(ring, &ptr, &ptr_len, info, timeout_ms);
         if (ret != SPMS_ERR_OK)
             return ret;
-        if (ptr_len > *len)
+        if (ptr_len > *len) {
+            *len = ptr_len;
             return SPMS_ERR_INVALID_ARG;
+        }
 
         memcpy(addr, ptr, ptr_len);
         if (spms_sub_finalize_read(ring) == 0)