DTO async user-level function API

[byrnedj]

This commit adds support for the async DTO API. This public API allows the caller to pass an arbitrary function to execute while the DSA job is executing.

• void dto_memcpy_async(void *dest, const void src, size_t n, callback_t cb, void args);

where callback_t cb is a function pointer in the calling application.

[Copilot]

Pull Request Overview

Adds a non-blocking memcpy API that invokes a user-provided callback during DSA offload and updates docs and installation rules.

• Introduced dto_memcpy_async declaration and callback type in dto.h
• Implemented async memcpy in dto.c, extended enums, constants, and log output
• Documented the new API in README.md and updated header install in Makefile

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
dto.h	Declare new async memcpy API and callback type
dto.c	Implement dto_memcpy_async, update enums/constants
README.md	Document dto_memcpy_async usage
Makefile	Install dto.h to system include directory

Comments suppressed due to low confidence (3)

README.md:39

• [nitpick] Use a C code fence (```c) instead of bash for the C function signature to improve readability and syntax highlighting.

```bash

dto.h:11

• dto.h uses size_t but does not include <stddef.h>. Add #include <stddef.h> to define size_t.

void dto_memcpy_async(void *dest, const void *src, size_t n, callback_t cb, void* args);

dto.c:1513

• The callback cb is invoked unconditionally; add a null check (if (cb) cb(args);) to avoid dereferencing a null pointer.

__attribute__((visibility("default"))) void dto_memcpy_async(void *dest, const void *src, size_t n, callback_t cb, void* args) {

[Copilot]

[nitpick] Avoid hardcoding /usr/include; use $(PREFIX)/include or DESTDIR to respect custom install paths and cross-compilation scenarios.

Suggested change

	cp dto.h /usr/include/
	cp dto.h $(DESTDIR)$(PREFIX)/include/