stmhal/moduselect: Implement "oneshot polling" flag.

pfalcon · dpgeorge · commit be3ae9d13c81 · 2015-12-16T11:07:58.000Z
Similar to recently added feature in unix port: if event triggers for an
objects, its polling flags are automatically reset, so it won't be polled
until they are set again explicitly.
diff --git a/stmhal/moduselect.c b/stmhal/moduselect.c
@@ -33,6 +33,9 @@
 #include "py/mphal.h"
 #include "pybioctl.h"
 
+// Flags for poll()
+#define FLAG_ONESHOT (1)
+
 /// \module select - Provides select function to wait for events on a stream
 ///
 /// This module provides the select function.
@@ -223,13 +226,17 @@ STATIC mp_obj_t poll_poll(uint n_args, const mp_obj_t *args) {
 
     // work out timeout (its given already in ms)
     mp_uint_t timeout = -1;
-    if (n_args == 2) {
+    int flags = 0;
+    if (n_args >= 2) {
         if (args[1] != mp_const_none) {
             mp_int_t timeout_i = mp_obj_get_int(args[1]);
             if (timeout_i >= 0) {
                 timeout = timeout_i;
             }
         }
+        if (n_args >= 3) {
+            flags = mp_obj_get_int(args[2]);
+        }
     }
 
     mp_uint_t start_tick = mp_hal_ticks_ms();
@@ -249,14 +256,18 @@ STATIC mp_obj_t poll_poll(uint n_args, const mp_obj_t *args) {
                 if (poll_obj->flags_ret != 0) {
                     mp_obj_t tuple[2] = {poll_obj->obj, MP_OBJ_NEW_SMALL_INT(poll_obj->flags_ret)};
                     ret_list->items[n_ready++] = mp_obj_new_tuple(2, tuple);
+                    if (flags & FLAG_ONESHOT) {
+                        // Don't poll next time, until new event flags will be set explicitly
+                        poll_obj->flags = 0;
+                    }
                 }
             }
             return ret_list;
         }
         __WFI();
     }
 }
-MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(poll_poll_obj, 1, 2, poll_poll);
+MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(poll_poll_obj, 1, 3, poll_poll);
 
 STATIC const mp_map_elem_t poll_locals_dict_table[] = {
     { MP_OBJ_NEW_QSTR(MP_QSTR_register), (mp_obj_t)&poll_register_obj },

Original file line number	Diff line number	Diff line change
`@@ -33,6 +33,9 @@`
`33`	`33`	`#include "py/mphal.h"`
`34`	`34`	`#include "pybioctl.h"`
`35`	`35`
	`36`	`+// Flags for poll()`
	`37`	`+#define FLAG_ONESHOT (1)`
	`38`	`+`
`36`	`39`	`/// \module select - Provides select function to wait for events on a stream`
`37`	`40`	`///`
`38`	`41`	`/// This module provides the select function.`
`@@ -223,13 +226,17 @@ STATIC mp_obj_t poll_poll(uint n_args, const mp_obj_t *args) {`
`223`	`226`
`224`	`227`	`// work out timeout (its given already in ms)`
`225`	`228`	`mp_uint_t timeout = -1;`
`226`		`- if (n_args == 2) {`
	`229`	`+ int flags = 0;`
	`230`	`+ if (n_args >= 2) {`
`227`	`231`	`if (args[1] != mp_const_none) {`
`228`	`232`	`mp_int_t timeout_i = mp_obj_get_int(args[1]);`
`229`	`233`	`if (timeout_i >= 0) {`
`230`	`234`	`timeout = timeout_i;`
`231`	`235`	`}`
`232`	`236`	`}`
	`237`	`+ if (n_args >= 3) {`
	`238`	`+ flags = mp_obj_get_int(args[2]);`
	`239`	`+ }`
`233`	`240`	`}`
`234`	`241`
`235`	`242`	`mp_uint_t start_tick = mp_hal_ticks_ms();`
`@@ -249,14 +256,18 @@ STATIC mp_obj_t poll_poll(uint n_args, const mp_obj_t *args) {`
`249`	`256`	`if (poll_obj->flags_ret != 0) {`
`250`	`257`	`mp_obj_t tuple[2] = {poll_obj->obj, MP_OBJ_NEW_SMALL_INT(poll_obj->flags_ret)};`
`251`	`258`	`ret_list->items[n_ready++] = mp_obj_new_tuple(2, tuple);`
	`259`	`+ if (flags & FLAG_ONESHOT) {`
	`260`	`+ // Don't poll next time, until new event flags will be set explicitly`
	`261`	`+ poll_obj->flags = 0;`
	`262`	`+ }`
`252`	`263`	`}`
`253`	`264`	`}`
`254`	`265`	`return ret_list;`
`255`	`266`	`}`
`256`	`267`	`__WFI();`
`257`	`268`	`}`
`258`	`269`	`}`
`259`		`-MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(poll_poll_obj, 1, 2, poll_poll);`
	`270`	`+MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(poll_poll_obj, 1, 3, poll_poll);`
`260`	`271`
`261`	`272`	`STATIC const mp_map_elem_t poll_locals_dict_table[] = {`
`262`	`273`	`{ MP_OBJ_NEW_QSTR(MP_QSTR_register), (mp_obj_t)&poll_register_obj },`