Allow pre-commit hook to sync c10 headers between ET and pytorch

.githooks/pre-commit

@@ -1,36 +1,29 @@
 #!/usr/bin/env bash
 
-# Pre-commit hook to automatically update PyTorch commit pin when torch_pin.py changes
+# Pre-commit hook to automatically update PyTorch commit pin and sync c10 directories when torch_pin.py changes
 
 # Check if torch_pin.py is being committed
 if git diff --cached --name-only | grep -q "^torch_pin.py$"; then
     echo "🔍 Detected changes to torch_pin.py"
-    echo "📝 Updating PyTorch commit pin..."
+    echo "📝 Updating PyTorch commit pin and syncing c10 directories..."
 
-    # Run the update script
-    hook_output=$(python .github/scripts/update_pytorch_pin.py 2>&1)
-    hook_status=$?
-    echo "$hook_output"
-
-    if [ $hook_status -eq 0 ]; then
-        # Check if pytorch.txt was modified
+    # Run the update script (which now also syncs c10 directories)
+    if python .github/scripts/update_pytorch_pin.py; then
+        # Stage any modified files (pytorch.txt and grafted c10 files)
         if ! git diff --quiet .ci/docker/ci_commit_pins/pytorch.txt; then
-            echo "✅ PyTorch commit pin updated successfully"
-            # Stage the updated file
             git add .ci/docker/ci_commit_pins/pytorch.txt
             echo "📌 Staged .ci/docker/ci_commit_pins/pytorch.txt"
-        else
-            echo "ℹ️  PyTorch commit pin unchanged"
         fi
-    else
-        if echo "$hook_output" | grep -qi "rate limit exceeded"; then
-            echo "⚠️  PyTorch commit pin not updated due to GitHub API rate limiting."
-            echo "   Please manually update .ci/docker/ci_commit_pins/pytorch.txt if needed."
-        else
-            echo "❌ Failed to update PyTorch commit pin"
-            echo "Please run: python .github/scripts/update_pytorch_pin.py"
-            exit 1
+
+        # Stage any grafted c10 files
+        if ! git diff --quiet runtime/core/portable_type/c10/; then
+            git add runtime/core/portable_type/c10/
+            echo "📌 Staged grafted c10 files"
         fi
+    else
+        echo "❌ Failed to update PyTorch commit pin"
+        echo "Please run: python .github/scripts/update_pytorch_pin.py"
+        exit 1
     fi
 fi
 

.github/scripts/update_pytorch_pin.py

@@ -1,9 +1,12 @@
 #!/usr/bin/env python3
 
+import base64
+import hashlib
 import json
 import re
 import sys
 import urllib.request
+from pathlib import Path
 
 
 def parse_nightly_version(nightly_version):
@@ -101,6 +104,144 @@ def update_pytorch_pin(commit_hash):
     print(f"Updated {pin_file} with commit hash: {commit_hash}")
 
 
+def should_skip_file(filename):
+    """
+    Check if a file should be skipped during sync (build files).
+
+    Args:
+        filename: Base filename to check
+
+    Returns:
+        True if file should be skipped
+    """
+    skip_files = {"BUCK", "CMakeLists.txt", "TARGETS", "targets.bzl"}
+    return filename in skip_files
+
+
+def fetch_file_content(commit_hash, file_path):
+    """
+    Fetch file content from GitHub API.
+
+    Args:
+        commit_hash: Commit hash to fetch from
+        file_path: File path in the repository
+
+    Returns:
+        File content as bytes
+    """
+    api_url = f"https://api.github.com/repos/pytorch/pytorch/contents/{file_path}?ref={commit_hash}"
+
+    req = urllib.request.Request(api_url)
+    req.add_header("Accept", "application/vnd.github.v3+json")
+    req.add_header("User-Agent", "ExecuTorch-Bot")
+
+    try:
+        with urllib.request.urlopen(req) as response:
+            data = json.loads(response.read().decode())
+            # Content is base64 encoded
+            content = base64.b64decode(data["content"])
+            return content
+    except urllib.request.HTTPError as e:
+        print(f"Error fetching file {file_path}: {e}", file=sys.stderr)
+        raise
+
+
+def sync_directory(et_dir, pt_path, commit_hash):
+    """
+    Sync files from PyTorch to ExecuTorch using GitHub API.
+    Only syncs files that already exist in ExecuTorch - does not add new files.
+
+    Args:
+        et_dir: ExecuTorch directory path
+        pt_path: PyTorch directory path in the repository (e.g., "c10")
+        commit_hash: Commit hash to fetch from
+
+    Returns:
+        Number of files grafted
+    """
+    files_grafted = 0
+    print(f"Checking {et_dir} vs pytorch/{pt_path}...")
+
+    if not et_dir.exists():
+        print(f"Warning: ExecuTorch directory {et_dir} does not exist, skipping")
+        return 0
+
+    # Loop through files in ExecuTorch directory
+    for et_file in et_dir.rglob("*"):
+        if not et_file.is_file():
+            continue
+
+        # Skip build files
+        if should_skip_file(et_file.name):
+            continue
+
+        # Construct corresponding path in PyTorch
+        rel_path = et_file.relative_to(et_dir)
+        pt_file_path = f"{pt_path}/{rel_path}".replace("\\", "/")
+
+        # Fetch content from PyTorch and compare
+        try:
+            pt_content = fetch_file_content(commit_hash, pt_file_path)
+            et_content = et_file.read_bytes()
+
+            if pt_content != et_content:
+                print(f"⚠️  Difference detected in {rel_path}")
+                print(f"📋 Grafting from PyTorch commit {commit_hash}...")
+
+                et_file.write_bytes(pt_content)
+                print(f"✅ Grafted {et_file}")
+                files_grafted += 1
+        except urllib.request.HTTPError as e:
+            if e.code != 404:  # It's ok to have more files in ET than pytorch/pytorch.
+                print(f"Error fetching {rel_path} from PyTorch: {e}")
+        except Exception as e:
+            print(f"Error syncing {rel_path}: {e}")
+            continue
+
+    return files_grafted
+
+
+def sync_c10_directories(commit_hash):
+    """
+    Sync c10 and torch/headeronly directories from PyTorch to ExecuTorch using GitHub API.
+
+    Args:
+        commit_hash: PyTorch commit hash to sync from
+
+    Returns:
+        Total number of files grafted
+    """
+    print("\n🔄 Syncing c10 directories from PyTorch via GitHub API...")
+
+    # Get repository root
+    repo_root = Path.cwd()
+
+    # Define directory pairs to sync (from check_c10_sync.sh)
+    # Format: (executorch_dir, pytorch_path_in_repo)
+    dir_pairs = [
+        (
+            repo_root / "runtime/core/portable_type/c10/c10",
+            "c10",
+        ),
+        (
+            repo_root / "runtime/core/portable_type/c10/torch/headeronly",
+            "torch/headeronly",
+        ),
+    ]
+
+    total_grafted = 0
+    for et_dir, pt_path in dir_pairs:
+        files_grafted = sync_directory(et_dir, pt_path, commit_hash)
+        total_grafted += files_grafted
+
+    if total_grafted > 0:
+        print(f"\n✅ Successfully grafted {total_grafted} file(s) from PyTorch")
+    else:
+        print("\n✅ No differences found - c10 is in sync")
+
+    return total_grafted
+
+
 def main():
     try:
         # Read NIGHTLY_VERSION from torch_pin.py
@@ -118,7 +259,12 @@ def main():
         # Update the pin file
         update_pytorch_pin(commit_hash)
 
-        print("Successfully updated PyTorch commit pin!")
+        # Sync c10 directories from PyTorch
+        sync_c10_directories(commit_hash)
+
+        print(
+            "\n✅ Successfully updated PyTorch commit pin and synced c10 directories!"
+        )
 
     except Exception as e:
         print(f"Error: {e}", file=sys.stderr)