Espressif ESP32-S2 Programming Manual page 613

Chapter 2. API Reference
.ctx
.ctx_free_fn
};
/* Now register the property */
esp_local_ctrl_add_property(&timestamp);
Also notice that there is a ctx field, which is set to point to some custom func_get_time(). This can be used inside the
property get / set handlers to retrieve timestamp.
Here is an example of get_prop_values() handler, which is used for retrieving the timestamp.
static esp_err_t
values,
→
{
for (uint32_t
ESP_LOGI(TAG,
if (props[i].type
/* Obtain the timer function from ctx */
int32_t
/* Use static variable for saving the value.
* This is essential because the value has to be
* valid even after this function returns.
* Alternative is to use dynamic allocation
* and set the free_fn field */
static
prop_values[i].data
}
}
return ESP_OK;
}
Here is an example of set_prop_values() handler. Notice how we restrict from writing to read-only properties.
static esp_err_t
*prop_values,
→
{
for (uint32_t
if (props[i].flags
ESP_LOGE(TAG,
props[i].name);
→
return
} else
ESP_LOGI(TAG,
/* For keeping it simple, lets only log the incoming data */
ESP_LOG_BUFFER_HEX_LEVEL(TAG, prop_values[i].data,
}
}
return ESP_OK;
}
For complete example see
Espressif Systems
= func_get_time,
= NULL
get_property_values(size_t
i = 0; i < props_count; i++) {
"Reading %s", props[i].name);
== TYPE_TIMESTAMP) {
(*func_get_time)(void)
int32_t ts = func_get_time();
= &ts;
set_property_values(size_t
i = 0; i < props_count; i++) {
& READONLY) {
"Cannot write to read-only property
ESP_ERR_INVALID_ARG;
{
"Setting
protocols/esp_local_ctrl
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props_count,
const esp_local_ctrl_prop_t *props,
esp_local_ctrl_prop_val_t *prop_
void *usr_ctx)
= props[i].ctx;
props_count,
const esp_local_ctrl_prop_t *props,
const esp_local_ctrl_prop_val_t␣
void *usr_ctx)
%s", props[i].name);
prop_values[i].size, ESP_LOG_INFO);
602
(continued from previous page)
%s",␣
Release v4.4