From dc18f71004a6d8a53eab84f7c27038cb4e694fa7 Mon Sep 17 00:00:00 2001
From: Ryan Blue <ryanzblue@gmail.com>
Date: Thu, 29 Aug 2024 00:34:28 -0400
Subject: [PATCH] [wpilibc] Refactor AnalogTrigger to use shared_ptr (#7010)

---
 wpilibc/src/main/native/cpp/AnalogTrigger.cpp | 32 +++++++-----
 .../main/native/include/frc/AnalogTrigger.h   | 51 +++++++++++++++----
 2 files changed, 61 insertions(+), 22 deletions(-)

diff --git a/wpilibc/src/main/native/cpp/AnalogTrigger.cpp b/wpilibc/src/main/native/cpp/AnalogTrigger.cpp
index ea33c73f8d..e3f117b8e7 100644
--- a/wpilibc/src/main/native/cpp/AnalogTrigger.cpp
+++ b/wpilibc/src/main/native/cpp/AnalogTrigger.cpp
@@ -18,24 +18,36 @@
 using namespace frc;
 
 AnalogTrigger::AnalogTrigger(int channel)
-    : AnalogTrigger(new AnalogInput(channel)) {
+    : AnalogTrigger(std::make_shared<AnalogInput>(channel)) {
   m_ownsAnalog = true;
-  wpi::SendableRegistry::AddChild(this, m_analogInput);
+  wpi::SendableRegistry::AddChild(this, m_analogInput.get());
 }
 
-AnalogTrigger::AnalogTrigger(AnalogInput* input) {
-  m_analogInput = input;
+AnalogTrigger::AnalogTrigger(AnalogInput& input)
+    : AnalogTrigger{{&input, wpi::NullDeleter<AnalogInput>{}}} {}
+
+AnalogTrigger::AnalogTrigger(AnalogInput* input)
+    : AnalogTrigger{{input, wpi::NullDeleter<AnalogInput>{}}} {}
+
+AnalogTrigger::AnalogTrigger(std::shared_ptr<AnalogInput> input)
+    : m_analogInput{std::move(input)} {
   int32_t status = 0;
-  m_trigger = HAL_InitializeAnalogTrigger(input->m_port, &status);
-  FRC_CheckErrorStatus(status, "Channel {}", input->GetChannel());
+  m_trigger = HAL_InitializeAnalogTrigger(m_analogInput->m_port, &status);
+  FRC_CheckErrorStatus(status, "Channel {}", m_analogInput->GetChannel());
   int index = GetIndex();
 
   HAL_Report(HALUsageReporting::kResourceType_AnalogTrigger, index + 1);
   wpi::SendableRegistry::AddLW(this, "AnalogTrigger", index);
 }
 
-AnalogTrigger::AnalogTrigger(DutyCycle* input) {
-  m_dutyCycle = input;
+AnalogTrigger::AnalogTrigger(DutyCycle& input)
+    : AnalogTrigger{{&input, wpi::NullDeleter<DutyCycle>{}}} {}
+
+AnalogTrigger::AnalogTrigger(DutyCycle* input)
+    : AnalogTrigger{{input, wpi::NullDeleter<DutyCycle>{}}} {}
+
+AnalogTrigger::AnalogTrigger(std::shared_ptr<DutyCycle> input)
+    : m_dutyCycle{input} {
   int32_t status = 0;
   m_trigger = HAL_InitializeAnalogTriggerDutyCycle(input->m_handle, &status);
   FRC_CheckErrorStatus(status, "Channel {}", m_dutyCycle->GetSourceChannel());
@@ -49,10 +61,6 @@ AnalogTrigger::~AnalogTrigger() {
   int32_t status = 0;
   HAL_CleanAnalogTrigger(m_trigger, &status);
   FRC_ReportError(status, "Channel {}", GetSourceChannel());
-
-  if (m_ownsAnalog) {
-    delete m_analogInput;
-  }
 }
 
 void AnalogTrigger::SetLimitsVoltage(double lower, double upper) {
diff --git a/wpilibc/src/main/native/include/frc/AnalogTrigger.h b/wpilibc/src/main/native/include/frc/AnalogTrigger.h
index f9c5602666..d987ec037d 100644
--- a/wpilibc/src/main/native/include/frc/AnalogTrigger.h
+++ b/wpilibc/src/main/native/include/frc/AnalogTrigger.h
@@ -31,27 +31,61 @@ class AnalogTrigger : public wpi::Sendable,
   explicit AnalogTrigger(int channel);
 
   /**
-   * Construct an analog trigger given an analog input.
+   * Construct an analog trigger using an existing analog input.
    *
    * This should be used in the case of sharing an analog channel between the
    * trigger and an analog input object.
    *
-   * @param input The pointer to the existing AnalogInput object
+   * @param input A reference to the existing AnalogInput object
+   */
+  explicit AnalogTrigger(AnalogInput& input);
+
+  /**
+   * Construct an analog trigger using an existing analog input.
+   *
+   * This should be used in the case of sharing an analog channel between the
+   * trigger and an analog input object.
+   *
+   * @param input A pointer to the existing AnalogInput object
    */
   explicit AnalogTrigger(AnalogInput* input);
 
   /**
-   * Construct an analog trigger given a duty cycle input.
+   * Construct an analog trigger using an existing analog input.
    *
-   * @param dutyCycle The pointer to the existing DutyCycle object
+   * This should be used in the case of sharing an analog channel between the
+   * trigger and an analog input object.
+   *
+   * @param input A shared_ptr to the existing AnalogInput object
+   */
+  explicit AnalogTrigger(std::shared_ptr<AnalogInput> input);
+
+  /**
+   * Construct an analog trigger using an existing duty cycle input.
+   *
+   * @param dutyCycle A reference to the existing DutyCycle object
+   */
+  explicit AnalogTrigger(DutyCycle& dutyCycle);
+
+  /**
+   * Construct an analog trigger using an existing duty cycle input.
+   *
+   * @param dutyCycle A pointer to the existing DutyCycle object
    */
   explicit AnalogTrigger(DutyCycle* dutyCycle);
 
-  ~AnalogTrigger() override;
+  /**
+   * Construct an analog trigger using an existing duty cycle input.
+   *
+   * @param dutyCycle A shared_ptr to the existing DutyCycle object
+   */
+  explicit AnalogTrigger(std::shared_ptr<DutyCycle> dutyCycle);
 
   AnalogTrigger(AnalogTrigger&&) = default;
   AnalogTrigger& operator=(AnalogTrigger&&) = default;
 
+  ~AnalogTrigger() override;
+
   /**
    * Set the upper and lower limits of the analog trigger.
    *
@@ -139,9 +173,6 @@ class AnalogTrigger : public wpi::Sendable,
   /**
    * Creates an AnalogTriggerOutput object.
    *
-   * Gets an output object that can be used for routing. Caller is responsible
-   * for deleting the AnalogTriggerOutput object.
-   *
    * @param type An enum of the type of output object to create.
    * @return A pointer to a new AnalogTriggerOutput object.
    */
@@ -153,9 +184,9 @@ class AnalogTrigger : public wpi::Sendable,
  private:
   int GetSourceChannel() const;
 
+  std::shared_ptr<AnalogInput> m_analogInput;
+  std::shared_ptr<DutyCycle> m_dutyCycle;
   hal::Handle<HAL_AnalogTriggerHandle> m_trigger;
-  AnalogInput* m_analogInput = nullptr;
-  DutyCycle* m_dutyCycle = nullptr;
   bool m_ownsAnalog = false;
 };