fuse: cache options

scripts/fusefuzz.py

@@ -0,0 +1,71 @@
+#!/usr/bin/env python3
+
+import os
+
+"""
+mkdir -p /dev/shm/fusefuzz/{r,v}
+PYTHONPATH=.. python3 -m copyparty -v /dev/shm/fusefuzz/r::r -i 127.0.0.1
+../bin/copyparty-fuse.py /dev/shm/fusefuzz/v http://127.0.0.1:3923/ 2 0
+(d="$PWD"; cd /dev/shm/fusefuzz && "$d"/fusefuzz.py)
+"""
+
+
+def main():
+    for n in range(5):
+        with open(f"r/{n}", "wb") as f:
+            f.write(b"h" * n)
+
+    for fsz in range(1024 * 1024 * 2 - 3, 1024 * 1024 * 2 + 3):
+        with open("r/f", "wb", fsz) as f:
+            f.write(b"\xab" * fsz)
+
+        for rsz in range(62, 66):
+            ofslist = [0, 1, 2]
+            for n in range(3):
+                ofslist.append(fsz - n)
+                ofslist.append(fsz - (rsz * 1 + n))
+                ofslist.append(fsz - (rsz * 2 + n))
+
+            for ofs0 in ofslist:
+                for shift in range(-3, 3):
+                    print(f"fsz {fsz} rsz {rsz} ofs {ofs0} shift {shift}")
+                    ofs = ofs0
+                    if ofs < 0 or ofs >= fsz:
+                        continue
+
+                    for n in range(1, 3):
+                        with open(f"v/{n}", "rb") as f:
+                            f.read()
+
+                    prev_ofs = -99
+                    with open("r/f", "rb", rsz) as rf:
+                        with open("v/f", "rb", rsz) as vf:
+                            while True:
+                                ofs += shift
+                                if ofs < 0 or ofs > fsz or ofs == prev_ofs:
+                                    break
+
+                                prev_ofs = ofs
+
+                                if ofs != rf.tell():
+                                    rf.seek(ofs)
+                                    vf.seek(ofs)
+
+                                rb = rf.read(rsz)
+                                vb = vf.read(rsz)
+
+                                print(
+                                    f"fsz {fsz} rsz {rsz} ofs {ofs0} shift {shift} ofs {ofs} = {len(rb)}"
+                                )
+
+                                if rb != vb:
+                                    raise Exception(f"{len(rb)} != {len(vb)}")
+
+                                if not rb:
+                                    break
+
+                                ofs += len(rb)
+
+
+if __name__ == "__main__":
+    main()