Christopher Haster
Note! This project has moved to github.com/armmbed/mbed-events
This repository has been superceded
This project has moved to mbed-events
Composable event loops combine the cheap synchronicity of event loops with the composability of preempted threads.
Two modular event queue classes are provided:
- EventLoop - for loops coupled with a c++ managed thread
- EventQueue - for manually managed event queues
The Event class takes advantage of the extensibility of FuncPtr to allow an event to be passed through APIs as a normal function.
More information on composable event loops.
Revision 20:2f9d9c53a5af, committed 2016-04-18
- Comitter:
- Christopher Haster
- Date:
- Mon Apr 18 13:22:21 2016 -0500
- Parent:
- 19:86ffaa34870b
- Commit message:
- Add event_pointer argument to avoid memory allocation
Changed in this revision
diff -r 86ffaa34870b -r 2f9d9c53a5af EventLoop.cpp
--- a/EventLoop.cpp Mon Apr 18 12:59:37 2016 -0500
+++ b/EventLoop.cpp Mon Apr 18 13:22:21 2016 -0500
@@ -5,9 +5,10 @@
EventLoop::EventLoop(osPriority priority,
unsigned event_count,
unsigned event_context,
+ unsigned char *event_pointer,
uint32_t stack_size,
unsigned char *stack_pointer)
- : EventQueue(event_count, event_context) {
+ : EventQueue(event_count, event_context, event_pointer) {
_running = false;
_priority = priority;
_stack_size = stack_size;
@@ -18,9 +19,10 @@
osPriority priority,
unsigned event_count,
unsigned event_context,
+ unsigned char *event_pointer,
uint32_t stack_size,
unsigned char *stack_pointer)
- : EventQueue(event_count, event_context) {
+ : EventQueue(event_count, event_context, event_pointer) {
_running = false;
_priority = priority;
_stack_size = stack_size;
diff -r 86ffaa34870b -r 2f9d9c53a5af EventLoop.h
--- a/EventLoop.h Mon Apr 18 12:59:37 2016 -0500
+++ b/EventLoop.h Mon Apr 18 13:22:21 2016 -0500
@@ -16,7 +16,11 @@
* @param priority Initial priority of the thread
* (default: osPriorityNormal)
* @param event_count Number of events to allow enqueueing at once
+ * (default: 32)
* @param event_context Max size of arguments passed with an event
+ * (default: 0)
+ * @param event_pointer Pointer to memory area to be used for events
+ * (default: NULL)
* @param stack_size Stack size (in bytes) requirements for the thread
* (default: DEFAULT_STACK_SIZE)
* @param stack_pointer Pointer to stack area to be used by the thread
@@ -25,6 +29,7 @@
EventLoop(osPriority priority=osPriorityNormal,
unsigned event_count=32,
unsigned event_context=0,
+ unsigned char *event_pointer=NULL,
uint32_t stack_size=DEFAULT_STACK_SIZE,
unsigned char *stack_pointer=NULL);
@@ -33,7 +38,11 @@
* @param priority Initial priority of the thread
* (default: osPriorityNormal)
* @param event_count Number of events to allow enqueueing at once
+ * (default: 32)
* @param event_context Max size of arguments passed with an event
+ * (default: 0)
+ * @param event_pointer Pointer to memory area to be used for events
+ * (default: NULL)
* @param stack_size Stack size (in bytes) requirements for the thread
* (default: DEFAULT_STACK_SIZE)
* @param stack_pointer Pointer to stack area to be used by the thread
@@ -43,6 +52,7 @@
osPriority priority=osPriorityNormal,
unsigned event_count=32,
unsigned event_context=0,
+ unsigned char *event_pointer=NULL,
uint32_t stack_size=DEFAULT_STACK_SIZE,
unsigned char *stack_pointer=NULL);
diff -r 86ffaa34870b -r 2f9d9c53a5af EventQueue.cpp
--- a/EventQueue.cpp Mon Apr 18 12:59:37 2016 -0500
+++ b/EventQueue.cpp Mon Apr 18 13:22:21 2016 -0500
@@ -17,18 +17,26 @@
// Event queue definitions
-EventQueue::EventQueue(unsigned event_count, unsigned event_context) {
+EventQueue::EventQueue(unsigned event_count,
+ unsigned event_context,
+ unsigned char *event_pointer) {
_event_context = sizeof(FuncPtr<void()>) + event_context;
unsigned event_size = sizeof(struct event) + _event_context;
- _mem = malloc(event_count * event_size);
- _free = (struct event*)_mem;
- if (_mem) {
+ if (!event_pointer) {
+ _mem = malloc(event_count * event_size);
+ _free = (struct event*)_mem;
+ } else {
+ _mem = 0;
+ _free = (struct event*)event_pointer;
+ }
+
+ if (_free) {
for (unsigned i = 0; i < event_count-1; i++) {
- ((struct event*)((char*)_mem + i*event_size))->next =
- (struct event*)((char*)_mem + (i+1)*event_size);
+ ((struct event*)((char*)_free + i*event_size))->next =
+ (struct event*)((char*)_free + (i+1)*event_size);
}
- ((struct event*)((char*)_mem + (event_count-1)*event_size))->next = 0;
+ ((struct event*)((char*)_free + (event_count-1)*event_size))->next = 0;
}
_queue = 0;
diff -r 86ffaa34870b -r 2f9d9c53a5af EventQueue.h
--- a/EventQueue.h Mon Apr 18 12:59:37 2016 -0500
+++ b/EventQueue.h Mon Apr 18 13:22:21 2016 -0500
@@ -17,10 +17,15 @@
public:
/** Create an event queue
* @param event_count Number of events to allow enqueueing at once
+ * (default: 32)
* @param event_context Max size of arguments passed with an event
+ * (default: 0)
+ * @param event_pointer Pointer to memory area to be used for events
+ * (default: NULL)
*/
EventQueue(unsigned event_count=32,
- unsigned event_context=0);
+ unsigned event_context=0,
+ unsigned char *event_pointer=NULL);
/** Clean up event queue
*/
@@ -79,6 +84,7 @@
unsigned _event_context;
void *_mem;
+
struct event *volatile _free;
struct event *volatile _queue;