update

tests/pre15/fixtures/B32-cache-generate.py

@@ -0,0 +1,125 @@
+#!/usr/bin/env python3
+from __future__ import annotations
+
+import argparse
+import hashlib
+import json
+import os
+from pathlib import Path
+import shutil
+import subprocess
+
+
+def sha256_bytes(data: bytes) -> str:
+    return hashlib.sha256(data).hexdigest()
+
+
+def sha256_path(path: Path) -> str:
+    return sha256_bytes(path.read_bytes())
+
+
+def run(argv: list[str], cwd: Path) -> None:
+    completed = subprocess.run(
+        argv,
+        cwd=cwd,
+        check=False,
+        stdout=subprocess.PIPE,
+        stderr=subprocess.STDOUT,
+        text=True,
+        timeout=120,
+    )
+    if completed.returncode != 0:
+        raise SystemExit(
+            f"command failed ({completed.returncode}): {' '.join(argv)}\n"
+            f"{completed.stdout}"
+        )
+
+
+def main() -> None:
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--spec", type=Path, required=True)
+    parser.add_argument("--output", type=Path, required=True)
+    args = parser.parse_args()
+    spec = json.loads(args.spec.read_text(encoding="ascii"))
+    if (
+        spec.get("schema") != 1
+        or spec.get("batch") != "B32"
+        or spec.get("test") != "TC168-cache-inflight"
+    ):
+        raise SystemExit("invalid B32 cache fixture spec")
+    if args.output.exists():
+        raise SystemExit(f"refusing existing B32 output: {args.output}")
+    if shutil.which("mkfs.erofs") is None:
+        raise SystemExit("mkfs.erofs is required")
+
+    source = (b"Pre15-B32-cache-state:0123456789abcdef\n" * 2000)[
+        : spec["source"]["size"]
+    ]
+    if sha256_bytes(source) != spec["source"]["sha256"]:
+        raise SystemExit("B32 deterministic source identity changed")
+
+    source_dir = args.output / "source"
+    images = args.output / "images"
+    source_dir.mkdir(parents=True)
+    images.mkdir()
+    payload = source_dir / "payload.bin"
+    payload.write_bytes(source)
+    os.utime(payload, (0, 0))
+    os.utime(source_dir, (0, 0))
+
+    valid = images / "lzma-valid.erofs"
+    run(["mkfs.erofs", *spec["mkfs_args"], str(valid), str(source_dir)], images)
+    valid_data = valid.read_bytes()
+    if len(valid_data) != 8192:
+        raise SystemExit(f"unexpected B32 image size: {len(valid_data)}")
+    pcluster_start = 4096
+    pcluster_end = 8192
+    pcluster = valid_data[pcluster_start:pcluster_end]
+    leading = next(
+        (index for index, value in enumerate(pcluster) if value), len(pcluster)
+    )
+    stream = pcluster[leading:]
+    if leading == len(pcluster) or len(stream) < 2:
+        raise SystemExit("B32 LZMA stream boundary is empty")
+
+    truncated_data = bytearray(valid_data)
+    truncated_data[pcluster_start + leading : pcluster_end] = b"\0" + stream[:-1]
+    if truncated_data == valid_data:
+        raise SystemExit("B32 truncated mutation changed no bytes")
+    truncated = images / "lzma-truncated.erofs"
+    truncated.write_bytes(truncated_data)
+
+    records = []
+    for image_class, path, expected_errno in (
+        ("valid", valid, 0),
+        ("truncated", truncated, 97),
+    ):
+        records.append(
+            {
+                "class": image_class,
+                "expected_errno": expected_errno,
+                "path": path.name,
+                "sha256": sha256_path(path),
+            }
+        )
+    index = {
+        "batch": "B32",
+        "decoded_size": len(source),
+        "fixture_count": len(records),
+        "fixtures": records,
+        "leading_zero_bytes": leading,
+        "physical_length": len(pcluster),
+        "physical_offset": pcluster_start,
+        "schema": 1,
+        "source_sha256": sha256_path(payload),
+        "status": "READY",
+        "test": "TC168-cache-inflight",
+    }
+    (args.output / "fixture-index.json").write_text(
+        json.dumps(index, indent=2, sort_keys=True) + "\n", encoding="ascii"
+    )
+    print(json.dumps(index, indent=2, sort_keys=True))
+
+
+if __name__ == "__main__":
+    main()