1 files changed, 83 insertions, 0 deletions
diff --git a/bitsandbytes/cuda_setup.py b/bitsandbytes/cuda_setup.py
new file mode 100644
index 0000000..48423b5
--- /dev/null
+++ b/bitsandbytes/cuda_setup.py
@@ -0,0 +1,83 @@
+"""
+build is dependent on
+- compute capability
+    - dependent on GPU family
+- CUDA version
+- Software:
+    - CPU-only: only CPU quantization functions (no optimizer, no matrix multipl)
+    - CuBLAS-LT: full-build 8-bit optimizer
+    - no CuBLAS-LT: no 8-bit matrix multiplication (`nomatmul`)
+
+alle Binaries packagen
+
+evaluation:
+    - if paths faulty, return meaningful error
+    - else:
+        - determine CUDA version
+        - determine capabilities
+        - based on that set the default path
+"""
+
+from os import environ as env
+from pathlib import Path
+from typing import Set, Union
+from .utils import warn_of_missing_prerequisite, print_err
+
+
+CUDA_RUNTIME_LIB: str = "libcudart.so"
+
+def tokenize_paths(paths: str) -> Set[Path]:
+    return {
+        Path(ld_path) for ld_path in paths.split(':')
+        if ld_path
+    }
+
+def get_cuda_runtime_lib_path(
+    # TODO: replace this with logic for all paths in env vars
+    LD_LIBRARY_PATH: Union[str, None] = env.get("LD_LIBRARY_PATH")
+) -> Union[Path, None]:
+    """ # TODO: add doc-string
+    """
+
+    if not LD_LIBRARY_PATH:
+        warn_of_missing_prerequisite(
+            'LD_LIBRARY_PATH is completely missing from environment!'
+        )
+        return None
+
+    ld_library_paths: Set[Path] = tokenize_paths(LD_LIBRARY_PATH)
+
+    non_existent_directories: Set[Path]  = {
+        path for path in ld_library_paths
+        if not path.exists()
+    }
+
+    if non_existent_directories:
+        print_err(
+            "WARNING: The following directories listed your path were found to "
+            f"be non-existent: {non_existent_directories}"
+        )
+
+    cuda_runtime_libs: Set[Path] = {
+        path / CUDA_RUNTIME_LIB for path in ld_library_paths
+        if (path / CUDA_RUNTIME_LIB).is_file()
+    } - non_existent_directories
+
+    if len(cuda_runtime_libs) > 1:
+        err_msg = f"Found duplicate {CUDA_RUNTIME_LIB} files: {cuda_runtime_libs}.."
+        raise FileNotFoundError(err_msg)
+
+    elif len(cuda_runtime_libs) < 1:
+        err_msg = f"Did not find {CUDA_RUNTIME_LIB} files: {cuda_runtime_libs}.."
+        raise FileNotFoundError(err_msg)
+
+    single_cuda_runtime_lib_dir = next(iter(cuda_runtime_libs))
+    return ld_library_paths
+
+def evaluate_cuda_setup():
+    # - if paths faulty, return meaningful error
+    # - else:
+    #     - determine CUDA version
+    #     - determine capabilities
+    #     - based on that set the default path
+    pass