riot-ci/RIOT
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

sys/cb_mux: initial support

Browse Source
This commit is contained in:
Matthew Blue 2018-04-19 22:53:49 -04:00
parent ab0071622b
commit 02697fafb3
3 changed files with 268 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
sys/cb_mux/Makefile Normal file
View File

@ -0,0 +1 @@
include $(RIOTBASE)/Makefile.base

124
sys/cb_mux/cb_mux.c Normal file
View File

@ -0,0 +1,124 @@
/*
* Copyright (C) 2018 Acutam Automation, LLC
*
* This file is subject to the terms and conditions of the GNU Lesser
* General Public License v2.1. See the file LICENSE in the top level
* directory for more details.
*/
/**
* @ingroup sys_cb_mux
* @{
*
* @file
* @brief cb_mux implementation
*
* @author Matthew Blue <matthew.blue.neuro@gmail.com>
* @}
*/
#include "cb_mux.h"
#include "utlist.h"
void cb_mux_add(cb_mux_t **head, cb_mux_t *entry)
{
LL_APPEND(*head, entry);
}
void cb_mux_del(cb_mux_t **head, cb_mux_t *entry)
{
LL_DELETE(*head, entry);
}
cb_mux_t *cb_mux_find_cbid(cb_mux_t *head, cb_mux_cbid_t cbid_val)
{
cb_mux_t *entry;
LL_SEARCH_SCALAR(head, entry, cbid, cbid_val);
return entry;
}
cb_mux_t *cb_mux_find_low(cb_mux_t *head)
{
cb_mux_t *entry;
cb_mux_t *entry_low = NULL;
cb_mux_cbid_t id = (cb_mux_cbid_t)(-1);
LL_FOREACH(head, entry) {
/* Entry does not have lower ID */
if (entry->cbid >= id) {
continue;
}
id = entry->cbid;
entry_low = entry;
}
return entry_low;
}
cb_mux_t *cb_mux_find_high(cb_mux_t *head)
{
cb_mux_t *entry;
cb_mux_t *entry_high = NULL;
cb_mux_cbid_t id = 0;
LL_FOREACH(head, entry) {
/* Entry does not have higher ID */
if (entry->cbid <= id) {
continue;
}
id = entry->cbid;
entry_high = entry;
}
return entry_high;
}
cb_mux_cbid_t cb_mux_find_free_id(cb_mux_t *head)
{
uint32_t free;
cb_mux_cbid_t block;
cb_mux_t *entry;
uint8_t num;
/* Search for free IDs in blocks of 32 IDs */
for (block = 0; block + 31 < (cb_mux_cbid_t)(-1); block += 32) {
/* Set all IDs in block to free */
free = 0;
LL_FOREACH(head, entry) {
/* cbid falls within this block */
if ((entry->cbid >= block) && (entry->cbid < block + 32)) {
/* Set cbid to taken */
free |= 1 << (entry->cbid & 0x1F);
}
}
/* At least one ID in block free */
if (~free) {
break;
}
}
/* Find which ID in block was free */
for (num = 0; num < 32; num++) {
if (~free & (1 << num)) {
return block | num;
}
}
/* No free IDs */
return (cb_mux_cbid_t)(-1);
}
void cb_mux_iter(cb_mux_t *head, cb_mux_iter_t func, void *arg)
{
cb_mux_t *entry;
LL_FOREACH(head, entry) {
func(entry, arg);
}
}

143
sys/include/cb_mux.h Normal file
View File

@ -0,0 +1,143 @@
/*
* Copyright (C) 2018 Acutam Automation, LLC
*
* This file is subject to the terms and conditions of the GNU Lesser
* General Public License v2.1. See the file LICENSE in the top level
* directory for more details.
*/
/**
* @defgroup sys_cb_mux Callback multiplexer
* @ingroup sys
* @brief cb_mux provides utilities for storing, retrieving, and managing
* callback information in a singly linked list.
*
* If an API provides the ability to call multiple callbacks, cb_mux can
* simplify handling of an arbitrary number of callbacks by requiring memory
* for a cb_mux entry to be passed along with other arguments. The cb_mux entry
* is then attached to a list using cb_mux_add. The code implementing that API
* can manage the list using the various utility functions that cb_mux provides.
*
* @{
*
* @file
* @brief cb_mux interface definitions
*
* @author Matthew Blue <matthew.blue.neuro@gmail.com>
*/
#ifndef CB_MUX_H
#define CB_MUX_H
#include <stdint.h>
/* For alternate cb_mux_cbid_t */
#include "periph_cpu.h"
#ifdef __cplusplus
extern "C" {
#endif
#ifndef HAVE_CB_MUX_CBID_T
/**
* @brief cb_mux identifier type
*/
typedef unsigned int cb_mux_cbid_t;
#endif
/**
* @brief cb_mux callback type
*/
typedef void (*cb_mux_cb_t)(void *);
/**
* @brief cb_mux list entry structure
*/
typedef struct cb_mux {
struct cb_mux *next; /**< next entry in the cb_mux list */
cb_mux_cbid_t cbid; /**< identifier for this callback */
void *info; /**< optional extra information */
cb_mux_cb_t cb; /**< callback function */
void *arg; /**< argument for callback function */
} cb_mux_t;
/**
* @brief cb_mux iterate function callback type for cb_mux_iter
*/
typedef void (*cb_mux_iter_t)(cb_mux_t *, void *);
/**
* @brief Add a new entry to the end of a cb_mux list
*
* @param[in] head double pointer to first list entry
* @param[in] entry entry to add
*/
void cb_mux_add(cb_mux_t **head, cb_mux_t *entry);
/**
* @brief Remove a entry from a cb_mux list
*
* @param[in] head double pointer to first list entry
* @param[in] entry entry to remove
*/
void cb_mux_del(cb_mux_t **head, cb_mux_t *entry);
/**
* @brief Find an entry in the list by ID
*
* @param[in] head pointer to first list entry
* @param[in] cbid_val ID to find
*
* @return pointer to the list entry
*/
cb_mux_t *cb_mux_find_cbid(cb_mux_t *head, cb_mux_cbid_t cbid_val);
/**
* @brief Find the entry with the lowest ID
*
* If there are multiple hits, this returns the oldest.
*
* @param[in] head pointer to first list entry
*
* @return pointer to the list entry
*/
cb_mux_t *cb_mux_find_low(cb_mux_t *head);
/**
* @brief Find the entry with the highest ID
*
* If there are multiple hits, this returns the oldest.
*
* @param[in] head pointer to first list entry
*
* @return pointer to the list entry
*/
cb_mux_t *cb_mux_find_high(cb_mux_t *head);
/**
* @brief Find the lowest unused ID
*
* Returns highest possible ID on failure
*
* @param[in] head pointer to first list entry
*
* @return lowest unused ID
*/
cb_mux_cbid_t cb_mux_find_free_id(cb_mux_t *head);
/**
* @brief Run a function on every item in the cb_mux list
*
* @param[in] head pointer to first list entry
* @param[in] func function to run on each entry
* @param[in] arg argument for the function
*/
void cb_mux_iter(cb_mux_t *head, cb_mux_iter_t func, void *arg);
#ifdef __cplusplus
}
#endif
/** @} */
#endif /* CB_MUX_H */