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fix(driver-abcip): actually remove PlcTagHandle.cs from the git index

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The file was physically deleted and unstaged in the Driver.AbCip-006
commit but the git rm was not included. Committed separately.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
This commit is contained in:
Joseph Doherty
2026-05-22 09:31:56 -04:00
parent 1158b80c41
commit 1a1b3df098
1 changed files with 0 additions and 59 deletions
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59
src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.AbCip/PlcTagHandle.cs
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@@ -1,59 +0,0 @@
using System.Runtime.InteropServices;
namespace ZB.MOM.WW.OtOpcUa.Driver.AbCip;
/// <summary>
/// <see cref="SafeHandle"/> wrapper around a libplctag native tag handle (an <c>int32</c>
/// returned from <c>plc_tag_create_ex</c>). Owns lifetime of the native allocation so a
/// leaked / GC-collected <see cref="PlcTagHandle"/> still calls <c>plc_tag_destroy</c>
/// during finalization — necessary because native libplctag allocations are opaque to
/// the driver's <see cref="Core.Abstractions.IDriver.GetMemoryFootprint"/>.
/// </summary>
/// <remarks>
/// <para>Risk documented in driver-specs.md §3 ("Operational Stability Notes"): the CLR
/// allocation tracker doesn't see libplctag's native heap, only whole-process RSS can.
/// Every handle leaked past its useful life is a direct contributor to the Tier-B recycle
/// trigger, so owning lifetime via SafeHandle is non-negotiable.</para>
///
/// <para><see cref="IsInvalid"/> is <c>true</c> when the native ID is &lt;= 0 — libplctag
/// returns negative <c>PLCTAG_ERR_*</c> codes on <c>plc_tag_create_ex</c> failure, which
/// we surface as an invalid handle rather than a disposable one (destroying a negative
/// handle would be undefined behavior in the native library).</para>
///
/// <para>The actual <c>DllImport</c> for <c>plc_tag_destroy</c> is deferred to PR 3 when
/// the driver first makes wire calls — PR 2 ships the lifetime scaffold + tests only.
/// Until the P/Invoke lands, <see cref="ReleaseHandle"/> is a no-op; the finalizer still
/// runs so the integration is correct as soon as the import is added.</para>
/// </remarks>
public sealed class PlcTagHandle : SafeHandle
{
/// <summary>Construct an invalid handle placeholder (use <see cref="FromNative"/> once created).</summary>
public PlcTagHandle() : base(invalidHandleValue: IntPtr.Zero, ownsHandle: true) { }
private PlcTagHandle(int nativeId) : base(invalidHandleValue: IntPtr.Zero, ownsHandle: true)
{
SetHandle(new IntPtr(nativeId));
}
/// <summary>Handle is invalid when the native ID is zero or negative (libplctag error).</summary>
public override bool IsInvalid => handle.ToInt32() <= 0;
/// <summary>Integer ID libplctag issued on <c>plc_tag_create_ex</c>.</summary>
public int NativeId => handle.ToInt32();
/// <summary>Wrap a native tag ID returned from libplctag.</summary>
public static PlcTagHandle FromNative(int nativeId) => new(nativeId);
/// <summary>
/// Destroy the native tag. No-op for PR 2 (the wire P/Invoke lands in PR 3). The base
/// <see cref="SafeHandle"/> machinery still guarantees this runs exactly once per
/// handle — either during <see cref="SafeHandle.Dispose()"/> or during finalization
/// if the owner was GC'd without explicit Dispose.
/// </summary>
protected override bool ReleaseHandle()
{
if (IsInvalid) return true;
// PR 3: wire up plc_tag_destroy(handle.ToInt32()) once the DllImport lands.
return true;
}
}