feat: add llama.cpp extension bindings

llama_cpp/llama_cpp_ext.py

@@ -0,0 +1,93 @@
+from __future__ import annotations
+
+import ctypes
+import functools
+
+from typing import Any, Iterable, Union
+
+from . import llama_cpp
+
+_lib = llama_cpp._lib
+
+
+def _ctypes_function_from_names(
+    names: Iterable[str],
+    argtypes: list[Any],
+    restype: Any,
+):
+    """Decorator for extension functions whose exported symbol name can vary by ABI."""
+
+    def decorator(f):
+        missing: list[str] = []
+        for name in names:
+            try:
+                func = getattr(_lib, name)
+            except AttributeError:
+                missing.append(name)
+                continue
+            func.argtypes = argtypes
+            func.restype = restype
+            functools.wraps(f)(func)
+            return func
+        raise AttributeError(
+            f"None of the shared library symbols were found: {', '.join(missing)}"
+        )
+
+    return decorator
+
+
+# LLAMA_API void llama_set_embeddings_pre_norm(struct llama_context * ctx, bool value, bool masked);
+@_ctypes_function_from_names(
+    (
+        "llama_set_embeddings_pre_norm",
+        "_Z29llama_set_embeddings_pre_normP13llama_contextbb",
+        "?llama_set_embeddings_pre_norm@@YAXPEAUllama_context@@_N1@Z",
+    ),
+    [llama_cpp.llama_context_p_ctypes, ctypes.c_bool, ctypes.c_bool],
+    None,
+)
+def llama_set_embeddings_pre_norm(
+    ctx: llama_cpp.llama_context_p,
+    value: bool,
+    masked: bool,
+    /,
+):
+    """Set whether the context outputs pre-norm embeddings or not."""
+    ...
+
+
+# LLAMA_API float * llama_get_embeddings_pre_norm(struct llama_context * ctx);
+@_ctypes_function_from_names(
+    (
+        "llama_get_embeddings_pre_norm",
+        "_Z29llama_get_embeddings_pre_normP13llama_context",
+        "?llama_get_embeddings_pre_norm@@YAPEAMPEAUllama_context@@@Z",
+    ),
+    [llama_cpp.llama_context_p_ctypes],
+    ctypes.POINTER(ctypes.c_float),
+)
+def llama_get_embeddings_pre_norm(
+    ctx: llama_cpp.llama_context_p,
+    /,
+):
+    """Get the pre-norm embeddings from the last evaluation."""
+    ...
+
+
+# LLAMA_API float * llama_get_embeddings_pre_norm_ith(struct llama_context * ctx, int32_t i);
+@_ctypes_function_from_names(
+    (
+        "llama_get_embeddings_pre_norm_ith",
+        "_Z33llama_get_embeddings_pre_norm_ithP13llama_contexti",
+        "?llama_get_embeddings_pre_norm_ith@@YAPEAMPEAUllama_context@@H@Z",
+    ),
+    [llama_cpp.llama_context_p_ctypes, ctypes.c_int32],
+    ctypes.POINTER(ctypes.c_float),
+)
+def llama_get_embeddings_pre_norm_ith(
+    ctx: llama_cpp.llama_context_p,
+    i: Union[ctypes.c_int32, int],
+    /,
+):
+    """Get the pre-norm embeddings for the ith output row from the last evaluation."""
+    ...