doc: clarify behavior of napi_get_typedarray_info

Signed-off-by: Michael Dawson <michael_dawson@ca.ibm.com>

Fixes: #32089

PR-URL: #32603
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Chengzhong Wu <legendecas@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>

doc/api/n-api.md

@@ -2391,7 +2391,8 @@ napi_status napi_get_arraybuffer_info(napi_env env,
 
 * `[in] env`: The environment that the API is invoked under.
 * `[in] arraybuffer`: `napi_value` representing the `ArrayBuffer` being queried.
-* `[out] data`: The underlying data buffer of the `ArrayBuffer`.
+* `[out] data`: The underlying data buffer of the `ArrayBuffer`. If byte_length
+  is `0`, this may be `NULL` or any other pointer value.
 * `[out] byte_length`: Length in bytes of the underlying data buffer.
 
 Returns `napi_ok` if the API succeeded.
@@ -2423,6 +2424,7 @@ napi_status napi_get_buffer_info(napi_env env,
 * `[in] env`: The environment that the API is invoked under.
 * `[in] value`: `napi_value` representing the `node::Buffer` being queried.
 * `[out] data`: The underlying data buffer of the `node::Buffer`.
+  If length is `0`, this may be `NULL` or any other pointer value.
 * `[out] length`: Length in bytes of the underlying data buffer.
 
 Returns `napi_ok` if the API succeeded.
@@ -2476,7 +2478,8 @@ napi_status napi_get_typedarray_info(napi_env env,
 * `[out] length`: The number of elements in the `TypedArray`.
 * `[out] data`: The data buffer underlying the `TypedArray` adjusted by
   the `byte_offset` value so that it points to the first element in the
-  `TypedArray`.
+  `TypedArray`. If the length of the array is `0`, this may be `NULL` or
+  any other pointer value.
 * `[out] arraybuffer`: The `ArrayBuffer` underlying the `TypedArray`.
 * `[out] byte_offset`: The byte offset within the underlying native array
   at which the first element of the arrays is located. The value for the data
@@ -2511,6 +2514,7 @@ napi_status napi_get_dataview_info(napi_env env,
   properties to query.
 * `[out] byte_length`: `Number` of bytes in the `DataView`.
 * `[out] data`: The data buffer underlying the `DataView`.
+  If byte_length is `0`, this may be `NULL` or any other pointer value.
 * `[out] arraybuffer`: `ArrayBuffer` underlying the `DataView`.
 * `[out] byte_offset`: The byte offset within the data buffer from which
   to start projecting the `DataView`.