Patch onnxruntime-genai to support latest (2026-02-01) onnxruntime

patch_onnxruntime_genai.py

#!/usr/bin/env python3
"""
Patch onnxruntime-genai.dll to replace "WebGPU_Buffer" string with "WebGPU_Buf".
"""

import os
import shutil
import sys

DLL_NAME = "onnxruntime-genai.dll"
BACKUP_NAME = "onnxruntime-genai.dll.bak"

# Original string to search for (ANSI C string)
SEARCH_BYTES = b"WebGPU_Buffer"
# We want to change "WebGPU_Buffer" to "WebGPU_Buf\x00er" (null-terminate after "Buf")
# This means replacing byte at position 10 (the second 'f') with 0x00
REPLACE_BYTES = b"WebGPU_Buf\x00er"


def main():
    # Check if DLL exists
    if not os.path.isfile(DLL_NAME):
        print(f"Error: {DLL_NAME} not found in current directory.", file=sys.stderr)
        sys.exit(1)

    # Read the DLL content
    print(f"Reading {DLL_NAME}...")
    with open(DLL_NAME, "rb") as f:
        data = f.read()

    # Count occurrences
    count = data.count(SEARCH_BYTES)
    print(f"Found {count} occurrence(s) of '{SEARCH_BYTES.decode('ascii')}'")

    if count == 0:
        print("Error: String not found in the file.", file=sys.stderr)
        sys.exit(1)

    if count != 1:
        print(f"Error: Expected exactly 1 occurrence, but found {count}.", file=sys.stderr)
        sys.exit(1)

    # Create backup
    print(f"Creating backup: {BACKUP_NAME}...")
    shutil.copy2(DLL_NAME, BACKUP_NAME)

    # Perform replacement
    print("Patching...")
    patched_data = data.replace(SEARCH_BYTES, REPLACE_BYTES, 1)

    # Verify the replacement
    if len(patched_data) != len(data):
        print("Error: Patched data size mismatch!", file=sys.stderr)
        sys.exit(1)

    # Write the patched DLL
    print(f"Writing patched {DLL_NAME}...")
    with open(DLL_NAME, "wb") as f:
        f.write(patched_data)

    print("Done! Patch applied successfully.")
    print(f"Backup saved as: {BACKUP_NAME}")


if __name__ == "__main__":
    main()