feat(core): sync io ops in core (#18603)

This commit adds op_read_sync and op_write_sync to core. These ops are
similar to op_read and op_write, but they are synchronous. Just like the
async ops, they operate on generic `deno_core::Resource` objects. These
now have new `read_byob_sync` and `write_sync` methods, with default
implementations throwing "NotSupported" errors, just like the async
counterparts.

There are no `write_all` or `read` equivalents, because the
optimizations they unlock are not useful in synchronous contexts.

1 files changed, 10 insertions, 0 deletions

diff --git a/core/lib.deno_core.d.ts b/core/lib.deno_core.d.ts
index b238bd6b3..7f3ea2a19 100644
--- a/core/lib.deno_core.d.ts
+++ b/core/lib.deno_core.d.ts
@@ -61,6 +61,16 @@ declare namespace Deno {
     function writeAll(rid: number, buf: Uint8Array): Promise<void>;
 
     /**
+     * Synchronously read from a (stream) resource that implements readSync().
+     */
+    function readSync(rid: number, buf: Uint8Array): number;
+
+    /**
+     * Synchronously write to a (stream) resource that implements writeSync().
+     */
+    function writeSync(rid: number, buf: Uint8Array): number;
+
+    /**
      * Print a message to stdout or stderr
      */
     function print(message: string, is_err?: boolean): void;