user
61 lines
1.7 KiB
Markdown
61 lines
1.7 KiB
Markdown
# K10 — Queue<T> and StaticQueue<T, N>
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K10 adds a typed C++ boundary over FreeRTOS byte-copy queues. Both wrappers
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unconditionally require `T` to be trivially copyable, pass `sizeof(T)` to the
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kernel and expose bounded `send`/`receive` calls whose default timeout is zero.
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- `Queue<T>` owns a dynamically created queue and deletes it in its destructor;
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- `StaticQueue<T,N>` references caller-owned `StaticQueueStorage<T,N>` in
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`.bss` and creates no heap allocation;
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- neither wrapper can be copied or moved.
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## Hazard3 evidence
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```text
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dynamic queue cost = 0x80 = 128 bytes
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Sample item size = 0x0c = 12 bytes
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received copied value = 0x1111 (source mutated to 0xDEAD)
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full send timeout = 2 ticks
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second FIFO value = 0x3333
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```
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Static creation leaves the heap unchanged. Its native handle equals the
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caller-supplied control block, and both control/storage addresses lie outside
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`ucHeap`. Destruction restores the exact dynamic baseline.
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## Build
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```sh
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make check
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```
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The host suite also compiles a trivial `Sample` and requires compilation of a
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minimal owning `VectorV1` message to fail with:
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```text
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Queue<T> requires T to be trivially copyable
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```
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## Debug
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```gdb
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b queue_debug_checkpoint
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p g_dynamic_queue_cost
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p g_static_control_address
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p g_static_bytes_address
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p g_static_first_item_bytes
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p g_copy_source_after_mutation
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p g_copy_received_value
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p g_full_count
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p g_timeout_ticks
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p g_fifo_values
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p g_queue_pass
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```
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## Scope boundary
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FreeRTOS queues copy bytes, not object lifetime. Owning objects must not cross
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this boundary by value. A pointer may be trivially copyable but then lifetime
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and ownership remain an explicit application contract. No wrapper silently
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uses `portMAX_DELAY`.
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