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Eliminate private TxItem
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@serges147
serges147 committed Nov 27, 2024
1 parent 36a5aec commit e8469fd
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Showing 3 changed files with 171 additions and 207 deletions.
89 changes: 39 additions & 50 deletions libudpard/udpard.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -272,23 +272,12 @@ static inline uint32_t transferCRCCompute(const size_t size, const void* const d
// ================================================= TX PIPELINE =================================================
// =====================================================================================================================

/// This is a subclass of UdpardTxItem. A pointer to this type can be cast to UdpardTxItem safely.
/// This is compliant with the C99 standard; paragraph 6.7.2.1.15 says:
/// A pointer to a structure object, suitably converted, points to its initial member (or if that member is a
/// bit-field, then to the unit in which it resides), and vice versa. There may be unnamed padding within a
/// structure object, but not at its beginning.
typedef struct
{
struct UdpardTxItem base;
enum UdpardPriority priority; ///< Do we need this exposed in the public structure? We already have DSCP there.
} TxItem;

/// Chain of TX frames prepared for insertion into a TX queue.
typedef struct
{
TxItem* head;
TxItem* tail;
size_t count;
struct UdpardTxItem* head;
struct UdpardTxItem* tail;
size_t count;
} TxChain;

static inline bool txValidateMemoryResources(const struct UdpardTxMemoryResources memory)
Expand All @@ -297,40 +286,40 @@ static inline bool txValidateMemoryResources(const struct UdpardTxMemoryResource
(memory.payload.allocate != NULL) && (memory.payload.deallocate != NULL);
}

static inline TxItem* txNewItem(const struct UdpardTxMemoryResources memory,
const uint_least8_t dscp_value_per_priority[UDPARD_PRIORITY_MAX + 1U],
const UdpardMicrosecond deadline_usec,
const enum UdpardPriority priority,
const struct UdpardUDPIPEndpoint endpoint,
const size_t datagram_payload_size,
void* const user_transfer_reference)
static inline struct UdpardTxItem* txNewItem(const struct UdpardTxMemoryResources memory,
const uint_least8_t dscp_value_per_priority[UDPARD_PRIORITY_MAX + 1U],
const UdpardMicrosecond deadline_usec,
const enum UdpardPriority priority,
const struct UdpardUDPIPEndpoint endpoint,
const size_t datagram_payload_size,
void* const user_transfer_reference)
{
TxItem* out = memAlloc(memory.fragment, sizeof(TxItem));
struct UdpardTxItem* out = memAlloc(memory.fragment, sizeof(struct UdpardTxItem));
if (out != NULL)
{
// No tree linkage by default.
out->base.base.up = NULL;
out->base.base.lr[0] = NULL;
out->base.base.lr[1] = NULL;
out->base.base.bf = 0;
out->base.up = NULL;
out->base.lr[0] = NULL;
out->base.lr[1] = NULL;
out->base.bf = 0;
// Init metadata.
out->priority = priority;
out->base.next_in_transfer = NULL; // Last by default.
out->base.deadline_usec = deadline_usec;
out->priority = priority;
out->next_in_transfer = NULL; // Last by default.
out->deadline_usec = deadline_usec;
UDPARD_ASSERT(priority <= UDPARD_PRIORITY_MAX);
out->base.dscp = dscp_value_per_priority[priority];
out->base.destination = endpoint;
out->base.user_transfer_reference = user_transfer_reference;
out->dscp = dscp_value_per_priority[priority];
out->destination = endpoint;
out->user_transfer_reference = user_transfer_reference;

void* const payload_data = memAlloc(memory.payload, datagram_payload_size);
if (NULL != payload_data)
{
out->base.datagram_payload.data = payload_data;
out->base.datagram_payload.size = datagram_payload_size;
out->datagram_payload.data = payload_data;
out->datagram_payload.size = datagram_payload_size;
}
else
{
memFree(memory.fragment, sizeof(TxItem), out);
memFree(memory.fragment, sizeof(struct UdpardTxItem), out);
out = NULL;
}
}
Expand All @@ -342,8 +331,8 @@ static inline TxItem* txNewItem(const struct UdpardTxMemoryResources memory,
static inline int_fast8_t txAVLPredicate(void* const user_reference, // NOSONAR Cavl API requires pointer to non-const.
const struct UdpardTreeNode* const node)
{
const TxItem* const target = (const TxItem*) user_reference;
const TxItem* const other = (const TxItem*) (const void*) node;
const struct UdpardTxItem* const target = (const struct UdpardTxItem*) user_reference;
const struct UdpardTxItem* const other = (const struct UdpardTxItem*) (const void*) node;
UDPARD_ASSERT((target != NULL) && (other != NULL));
return (target->priority >= other->priority) ? +1 : -1;
}
Expand Down Expand Up @@ -421,13 +410,13 @@ static inline TxChain txMakeChain(const struct UdpardTxMemoryResources memory,
size_t offset = 0U;
while (offset < payload_size_with_crc)
{
TxItem* const item = txNewItem(memory,
dscp_value_per_priority,
deadline_usec,
meta.priority,
endpoint,
smaller(payload_size_with_crc - offset, mtu) + HEADER_SIZE_BYTES,
user_transfer_reference);
struct UdpardTxItem* const item = txNewItem(memory,
dscp_value_per_priority,
deadline_usec,
meta.priority,
endpoint,
smaller(payload_size_with_crc - offset, mtu) + HEADER_SIZE_BYTES,
user_transfer_reference);
if (NULL == out.head)
{
out.head = item;
Expand All @@ -436,15 +425,15 @@ static inline TxChain txMakeChain(const struct UdpardTxMemoryResources memory,
{
// C std, 6.7.2.1.15: A pointer to a structure object <...> points to its initial member, and vice versa.
// Can't just read tqi->base because tqi may be NULL; https://github.com/OpenCyphal/libcanard/issues/203.
out.tail->base.next_in_transfer = (struct UdpardTxItem*) item;
out.tail->next_in_transfer = item;
}
out.tail = item;
if (NULL == out.tail)
{
break;
}
const bool last = (payload_size_with_crc - offset) <= mtu;
byte_t* const dst_buffer = item->base.datagram_payload.data;
byte_t* const dst_buffer = item->datagram_payload.data;
byte_t* write_ptr = txSerializeHeader(dst_buffer, meta, (uint32_t) out.count, last);
if (offset < payload.size)
{
Expand All @@ -460,7 +449,7 @@ static inline TxChain txMakeChain(const struct UdpardTxMemoryResources memory,
{
const size_t crc_offset = offset - payload.size;
UDPARD_ASSERT(crc_offset < TRANSFER_CRC_SIZE_BYTES);
const size_t available = item->base.datagram_payload.size - (size_t) (write_ptr - dst_buffer);
const size_t available = item->datagram_payload.size - (size_t) (write_ptr - dst_buffer);
UDPARD_ASSERT(available <= TRANSFER_CRC_SIZE_BYTES);
const size_t write_size = smaller(TRANSFER_CRC_SIZE_BYTES - crc_offset, available);
// NOLINTNEXTLINE(clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling)
Expand Down Expand Up @@ -509,7 +498,7 @@ static inline int32_t txPush(struct UdpardTx* const tx,
if (chain.tail != NULL)
{
UDPARD_ASSERT(frame_count == chain.count);
struct UdpardTxItem* next = &chain.head->base;
struct UdpardTxItem* next = chain.head;
do
{
const struct UdpardTreeNode* const res =
Expand All @@ -527,7 +516,7 @@ static inline int32_t txPush(struct UdpardTx* const tx,
else // The queue is large enough but we ran out of heap memory, so we have to unwind the chain.
{
out = -UDPARD_ERROR_MEMORY;
struct UdpardTxItem* head = &chain.head->base;
struct UdpardTxItem* head = chain.head;
while (head != NULL)
{
struct UdpardTxItem* const next = head->next_in_transfer;
Expand Down Expand Up @@ -694,7 +683,7 @@ void udpardTxFree(const struct UdpardTxMemoryResources memory, struct UdpardTxIt
memFree(memory.payload, item->datagram_payload.size, item->datagram_payload.data);
}

memFree(memory.fragment, sizeof(TxItem), item);
memFree(memory.fragment, sizeof(struct UdpardTxItem), item);
}
}

Expand Down
3 changes: 3 additions & 0 deletions libudpard/udpard.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -482,6 +482,9 @@ struct UdpardTxItem
/// LibUDPard selects the DSCP value based on the transfer priority level and the configured DSCP mapping.
uint_least8_t dscp;

/// Holds original transfer priority level (before DSCP mapping, see above `dscp`).
enum UdpardPriority priority;

/// This UDP/IP datagram compiled by libudpard should be sent to this endpoint.
/// The endpoint is always at a multicast address.
struct UdpardUDPIPEndpoint destination;
Expand Down
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