diff options
Diffstat (limited to 'os/hal/src/hal_buffers.c')
-rw-r--r-- | os/hal/src/hal_buffers.c | 83 |
1 files changed, 65 insertions, 18 deletions
diff --git a/os/hal/src/hal_buffers.c b/os/hal/src/hal_buffers.c index f1e58445c..a06352c37 100644 --- a/os/hal/src/hal_buffers.c +++ b/os/hal/src/hal_buffers.c @@ -22,6 +22,8 @@ * @{
*/
+#include <string.h>
+
#include "hal.h"
/*===========================================================================*/
@@ -105,7 +107,7 @@ uint8_t *ibqGetEmptyBufferI(input_buffers_queue_t *ibqp) { *
* @iclass
*/
-void ibqPostBufferI(io_buffers_queue_t *ibqp, size_t size) {
+void ibqPostBufferI(input_buffers_queue_t *ibqp, size_t size) {
osalDbgCheckClassI();
osalDbgAssert(!ibqIsFullI(ibqp), "buffers queue full");
@@ -125,8 +127,8 @@ void ibqPostBufferI(io_buffers_queue_t *ibqp, size_t size) { }
/**
- * @brief Gets the next filled buffer from the queue.
- * @note The function always returns the same buffer if called repeatedly.
+ * @brief Gets the next data-filled buffer from the queue.
+ * @note The function always acquires the same buffer if called repeatedly.
* @post After calling the function the fields @p ptr and @p top are set
* at beginning and end of the buffer data or @NULL if the queue
* is empty.
@@ -137,27 +139,25 @@ void ibqPostBufferI(io_buffers_queue_t *ibqp, size_t size) { * - @a TIME_IMMEDIATE immediate timeout.
* - @a TIME_INFINITE no timeout.
* .
- * @return A pointer to filled buffer area.
+ * @return The operation status.
* @retval MSG_OK if a buffer has been acquired.
* @retval MSG_TIMEOUT if the specified time expired.
* @retval MSG_RESET if the queue has been reset.
*
* @iclass
*/
-msg_t ibqGetFullBufferTimeoutI(input_buffers_queue_t *ibqp,
- systime_t timeout) {
+msg_t ibqGetDataTimeoutI(input_buffers_queue_t *ibqp, systime_t timeout) {
osalDbgCheckClassI();
while (ibqIsEmptyI(ibqp)) {
msg_t msg = osalThreadEnqueueTimeoutS(&ibqp->waiting, timeout);
if (msg < Q_OK) {
- ibqp->ptr = NULL;
return msg;
}
}
- /* Buffer boundaries.*/
+ /* Setting up the "current" buffer and its boundary.*/
ibqp->ptr = ibqp->brdptr + sizeof (size_t);
ibqp->top = ibqp->ptr + *((size_t *)ibqp->brdptr);
@@ -165,13 +165,14 @@ msg_t ibqGetFullBufferTimeoutI(input_buffers_queue_t *ibqp, }
/**
- * @brief Releases the next filled buffer back in the queue.
+ * @brief Releases the data buffer back in the queue.
+ * @note The object callback is called after releasing the buffer.
*
* @param[out] ibqp pointer to the @p input_buffers_queue_t object
*
* @iclass
*/
-void ibqReleaseBufferI(io_buffers_queue_t *ibqp) {
+void ibqReleaseDataI(input_buffers_queue_t *ibqp) {
osalDbgCheckClassI();
osalDbgAssert(!ibqIsEmptyI(ibqp), "buffers queue empty");
@@ -183,7 +184,7 @@ void ibqReleaseBufferI(io_buffers_queue_t *ibqp) { ibqp->brdptr = ibqp->buffers;
}
- /* Marked as no more sequentially accessible.*/
+ /* No "current" buffer.*/
ibqp->ptr = NULL;
/* Notifying the buffer release.*/
@@ -197,8 +198,6 @@ void ibqReleaseBufferI(io_buffers_queue_t *ibqp) { * @details This function reads a byte value from an input queue. If
* the queue is empty then the calling thread is suspended until a
* new buffer arrives in the queue or a timeout occurs.
- * @note The callback is invoked before reading the character from the
- * buffer or before entering the suspended state.
*
* @param[in] ibqp pointer to the @p input_buffers_queue_t object
* @param[in] timeout the number of ticks before the operation timeouts,
@@ -217,7 +216,7 @@ msg_t ibqGetTimeout(input_buffers_queue_t *ibqp, systime_t timeout) { /* This condition indicates that a new buffer must be acquired.*/
if (ibqp->ptr == NULL) {
- msg = ibqGetFullBufferTimeoutI(ibqp, timeout);
+ msg = ibqGetDataTimeoutI(ibqp, timeout);
if (msg != MSG_OK) {
return msg;
}
@@ -229,8 +228,8 @@ msg_t ibqGetTimeout(input_buffers_queue_t *ibqp, systime_t timeout) { /* If the current buffer has been fully read then it is returned as
empty in the queue.*/
- if (ibqp->ptr == ibqp->top) {
- ibqReleaseBufferI(ibqp);
+ if (ibqp->ptr >= ibqp->top) {
+ ibqReleaseDataI(ibqp);
}
return msg;
@@ -244,8 +243,6 @@ msg_t ibqGetTimeout(input_buffers_queue_t *ibqp, systime_t timeout) { * been reset.
* @note The function is not atomic, if you need atomicity it is suggested
* to use a semaphore or a mutex for mutual exclusion.
- * @note The callback is invoked before reading each character from the
- * buffer or before entering the state @p THD_STATE_WTQUEUE.
*
* @param[in] ibqp pointer to the @p input_buffers_queue_t object
* @param[out] bp pointer to the data buffer
@@ -262,7 +259,57 @@ msg_t ibqGetTimeout(input_buffers_queue_t *ibqp, systime_t timeout) { */
size_t ibqReadTimeout(input_buffers_queue_t *ibqp, uint8_t *bp,
size_t n, systime_t timeout) {
+ size_t r = 0;
+ systime_t deadline;
+
+ osalSysLock();
+
+ /* Time window for the whole operation.*/
+ deadline = osalOsGetSystemTimeX() + timeout;
+
+ while (r < n) {
+ size_t size;
+
+ /* This condition indicates that a new buffer must be acquired.*/
+ if (ibqp->ptr == NULL) {
+ systime_t next_timeout = deadline - osalOsGetSystemTimeX();
+
+ /* Handling the case where the system time went past the deadline,
+ in this case next becomes a very high number because the system
+ time is an unsigned type.*/
+ if (next_timeout > timeout)
+ return MSG_TIMEOUT;
+
+ msg_t msg = ibqGetDataTimeoutI(ibqp, next_timeout);
+ if (msg != MSG_OK) {
+ return msg;
+ }
+ }
+
+ /* Size of the data chunk present in the current buffer.*/
+ size = ibqp->top - ibqp->ptr;
+ if (size > n - r) {
+ size = n - r;
+ }
+
+ /* Copying the chunk into the read buffer, the operation is performed
+ outside the critical zone.*/
+ osalSysUnlock();
+ memcpy(bp, ibqp->ptr, size);
+ osalSysLock();
+
+ /* Updating the pointers.*/
+ bp += size;
+ ibqp->ptr += size;
+
+ /* Has the current data buffer been finished? if so then release it.*/
+ if (ibqp->ptr >= ibqp->top) {
+ ibqReleaseDataI(ibqp);
+ }
+ }
+ osalSysUnlock();
+ return r;
}
/** @} */
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