Replace Header Guards With #pragma once

[AarC10]

Description

Replace header guards with the more modern pragma once which we already use in our other codebases.

Type of change

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

Local compiles and CI

Checklist:

• New functionality is documented in the necessary spots (i.e new functions documented in the header)
• Unit tests cover any new functionality or edge cases that the PR was meant to resolve (if applicable)
• The CI checks are passing
• I reviewed my own code in the GitHub diff and am sure that each change is intentional
• I feel comfortable about this code flying in a rocket

[Copilot]

Pull request overview

This PR aims to modernize the codebase by replacing traditional header guards (#ifndef/#define/#endif) with #pragma once directives across all header files in the repository.

Changes:

• Replace header guards with #pragma once in all header files across launch_core_classic, f_core, sample applications, payload applications, ground applications, and backplane modules
• Remove closing #endif directives that were part of the old header guard system
• Standardize header protection mechanism across the entire codebase

Reviewed changes

Copilot reviewed 104 out of 104 changed files in this pull request and generated 25 comments.

Show a summary per file

File	Description
include/launch_core_classic/utils/event_monitor.h	Replaced header guard with #pragma once
include/launch_core_classic/types.h	Replaced header guard with #pragma once, inadvertently removed FLOAT_ERROR_VALUE macro
include/launch_core_classic/os/time.h	Incomplete: removed closing #endif but missing #pragma once addition
include/launch_core_classic/os/fs.h	Replaced header guard, inadvertently removed ENOTINIT and L_FS_CREATE_FILE macros
include/launch_core_classic/net/udp.h	Incomplete: removed closing #endif but missing #pragma once addition
include/launch_core_classic/net/tftp.h	Replaced header guard with #pragma once
include/launch_core_classic/net/sntp.h	Replaced header guard, inadvertently removed SNTP_CLIENT_STACK_SIZE macro
include/launch_core_classic/net/net_common.h	Incomplete: removed closing #endif but missing #pragma once addition
include/launch_core_classic/net/lora.h	Incomplete: removed closing #endif but missing #pragma once addition
include/launch_core_classic/extension_boards.h	Incomplete: only removed #define, left orphaned #ifndef
include/launch_core_classic/dev/uart.h	Replaced header guard with #pragma once
include/launch_core_classic/dev/sensor.h	Incomplete: removed closing #endif but missing #pragma once addition
include/launch_core_classic/dev/gnss.h	Incomplete: only removed #define, left orphaned #ifndef
include/launch_core_classic/dev/dev_common.h	Incomplete: removed closing #endif but missing #pragma once addition
include/launch_core_classic/dev/adc.h	Incomplete: removed closing #endif but missing #pragma once addition
include/launch_core_classic/conversions.h	Incomplete: only removed #define, left orphaned #ifndef and closing #endif
include/launch_core_classic/backplane_defs.h	Incomplete: only removed #define, left orphaned #ifndef
include/f_core/utils/n_time_utils.h	Replaced header guard but has orphaned #endif on line 32
include/f_core/utils/n_gnss_utils.h	Replaced header guard with #pragma once
include/f_core/utils/debouncer.hpp	Replaced header guard with #pragma once
include/f_core/utils/circular_buffer.hpp	Replaced header guard with #pragma once
include/f_core/utils/c_soft_timer.h	Replaced header guard with #pragma once
include/f_core/utils/c_observer.h	Replaced header guard with #pragma once
include/f_core/utils/c_hashmap.h	Replaced header guard with #pragma once
include/f_core/state_machine/c_pad_flight_landing_state_machine.h	Replaced header guard with #pragma once
include/f_core/radio/protocols/horus/horus.h	Has orphaned #endif directives from incomplete header guard removal
include/f_core/radio/frame_handlers/c_lora_freq_request_tenant.h	Replaced header guard with #pragma once
include/f_core/radio/frame_handlers/c_lora_frame_to_udp_handler.h	Replaced header guard with #pragma once
include/f_core/radio/frame_handlers/c_frequency_change_handler.h	Replaced header guard with #pragma once
include/f_core/radio/c_lora_router.h	Replaced header guard with #pragma once
include/f_core/radio/c_lora_link.h	Replaced header guard with #pragma once
include/f_core/radio/c_lora_frame_handler.h	Replaced header guard with #pragma once
include/f_core/radio/c_lora.h	Replaced header guard with #pragma once
include/f_core/radio/application/c_lora_tenant.h	Replaced header guard with #pragma once
include/f_core/os/tenants/c_datalogger_tenant.h	Replaced header guard with #pragma once
include/f_core/os/n_rtos.h	Replaced header guard with #pragma once
include/f_core/os/flight_log.hpp	Replaced header guard with #pragma once
include/f_core/os/c_tenant.h	Replaced header guard with #pragma once
include/f_core/os/c_task.h	Replaced header guard with #pragma once
include/f_core/os/c_runnable_tenant.h	Replaced header guard with #pragma once
include/f_core/os/c_latest_mailbox.h	Replaced header guard with #pragma once
include/f_core/os/c_file.h	Replaced header guard with #pragma once
include/f_core/os/c_datalogger.h	Replaced header guard with #pragma once
include/f_core/os/c_callback_tenant.h	Replaced header guard with #pragma once
include/f_core/net/transport/c_udp_socket.h	Replaced header guard with #pragma once
include/f_core/net/network/c_ipv4.h	Replaced header guard with #pragma once
include/f_core/net/device/c_rs485.h	Replaced header guard with #pragma once
include/f_core/net/c_transciever.h	Replaced header guard with #pragma once
include/f_core/net/application/c_udp_receiver_tenant.h	Replaced header guard with #pragma once
include/f_core/net/application/c_udp_broadcast_tenant.h	Replaced header guard with #pragma once
include/f_core/net/application/c_udp_alert_tenant.h	Replaced header guard with #pragma once
include/f_core/net/application/c_tftp_server_tenant.h	Replaced header guard with #pragma once
include/f_core/net/application/c_sntp_server_tenant.h	Replaced header guard with #pragma once
include/f_core/n_alerts.h	Replaced header guard with #pragma once
include/f_core/messaging/c_msgq_message_port.h	Replaced header guard with #pragma once
include/f_core/messaging/c_message_port.h	Replaced header guard with #pragma once
include/f_core/messaging/c_latest_message_port.h	Replaced header guard with #pragma once
include/f_core/flight/c_phase_controller.h	Replaced header guard with #pragma once
include/f_core/device/sensor/n_sensor_calibrators.h	Replaced header guard with #pragma once
include/f_core/device/sensor/c_temperature_sensor.h	Replaced header guard with #pragma once
include/f_core/device/sensor/c_shunt.h	Replaced header guard with #pragma once
include/f_core/device/sensor/c_sensor_device.h	Replaced header guard with #pragma once
include/f_core/device/sensor/c_magnetometer.h	Replaced header guard with #pragma once
include/f_core/device/sensor/c_gyroscope.h	Replaced header guard with #pragma once
include/f_core/device/sensor/c_barometer.h	Replaced header guard with #pragma once
include/f_core/device/sensor/c_accelerometer.h	Replaced header guard with #pragma once
include/f_core/device/c_rtc.h	Replaced header guard with #pragma once
include/f_core/device/c_gpio.h	Replaced header guard with #pragma once
include/f_core/c_project_configuration.h	Replaced header guard with #pragma once
app/samples/tftp_server/include/message.h	Replaced header guard with #pragma once
app/samples/tenants_and_tasks/include/c_print_count.h	Incomplete: added #pragma once but did not remove header guard closing #endif
app/samples/tenants_and_tasks/include/c_hello_tenant.h	Replaced header guard with #pragma once
app/samples/phase_detection/src/flight.h	Replaced header guard with #pragma once
app/samples/message_passing/include/message.h	Replaced header guard with #pragma once
app/samples/message_passing/include/c_receiver.h	Replaced header guard with #pragma once
app/samples/message_passing/include/c_publisher.h	Incomplete: added #pragma once but did not remove header guard closing #endif
app/payload/control_freak/flight-software/src/pump.h	Inadvertently removed multiple functional macros
app/payload/control_freak/flight-software/src/gps.h	Replaced header guard with #pragma once
app/payload/control_freak/flight-software/src/flight.h	Replaced header guard with #pragma once
app/payload/control_freak/flight-software/src/data.h	Replaced header guard, inadvertently removed IMU_SAMPLES_PER_PACKET macro
app/payload/control_freak/flight-software/src/common.h	Replaced header guard with #pragma once
app/payload/control_freak/flight-software/src/buzzer.h	Replaced header guard with #pragma once
app/payload/control_freak/flight-software/src/boost.h	Replaced header guard with #pragma once
app/payload/.retired/app_grim_reefer/src/data_storage.h	Replaced header guard with #pragma once
app/payload/.retired/app_grim_reefer/src/data_reading.h	Replaced header guard with #pragma once
app/payload/.retired/app_grim_reefer/src/config.h	Replaced header guard, inadvertently removed BUZZER_USE_LED and SHORT_FLIGHT macros
app/payload/.retired/app_grim_reefer/src/buzzer.h	Replaced header guard with #pragma once
app/payload/.retired/app_grim_reefer/src/boost_detect.h	Replaced header guard with #pragma once
app/other/.retired/app_potato/include/potato.h	Replaced header guard with #pragma once
app/ground/receiver_module/include/c_udp_listener_tenant.h	Replaced header guard with #pragma once
app/ground/receiver_module/include/c_receiver_module.h	Replaced header guard with #pragma once
app/backplane/sensor_module/include/c_sensor_module.h	Replaced header guard with #pragma once
app/backplane/sensor_module/include/c_sensing_tenant.h	Replaced header guard with #pragma once, has trailing whitespace
app/backplane/sensor_module/include/c_detection_handler.h	Added #pragma once (file previously had no header guard)
app/backplane/radio_module/include/c_udp_listener_tenant.h	Replaced header guard with #pragma once
app/backplane/radio_module/include/c_state_machine_updater.h	Replaced header guard with #pragma once
app/backplane/radio_module/include/c_remote_gpio_handler.h	Replaced header guard with #pragma once
app/backplane/radio_module/include/c_radio_module.h	Replaced header guard with #pragma once
app/backplane/radio_module/include/c_gnss_tenant.h	Replaced header guard with #pragma once
app/backplane/radio_module/include/c_downlink_scheduler_tenant.h	Replaced header guard with #pragma once
app/backplane/power_module/include/c_sensing_tenant.h	Replaced header guard with #pragma once
app/backplane/power_module/include/c_power_module.h	Replaced header guard with #pragma once
app/backplane/deployment_module/include/c_pyro_control_observer.h	Replaced header guard with #pragma once
app/backplane/deployment_module/include/c_deployment_module.h	Replaced header guard with #pragma once

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