pbio/sys/main: Expose how program was started.

This gives the user a way to optionally run certain code only when it is first downloaded to the robot. Examples include one-off motor initialization or one-off wiping of user data.

Fixes pybricks/support#1496

CHANGELOG.md

@@ -11,7 +11,8 @@
   coding ([support#1661]).
 - Added `observe_enable` to the hub `BLE` class to selectively turn observing
   on and off, just like you can with broadcasting ([support#1806]).
-- Added `hub.system.info()` method with hub status flags ([support#1496]).
+- Added `hub.system.info()` method with hub status flags ([support#1496]) and
+  value representing how the program was started.
 
 ### Changed
 

lib/pbio/include/pbsys/main.h

@@ -16,6 +16,30 @@
 #include <stdbool.h>
 #include <stdint.h>
 
+/**
+ * Whether and how the program was requested to start.
+ *
+ * Values are returned to the user, so the numeric values must not change.
+ */
+typedef enum {
+    /**
+     * The program was not requested to start.
+     */
+    PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_NONE = 0,
+    /**
+     * The program was requested to start automatically on boot.
+     */
+    PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_BOOT = 1,
+    /**
+     * The program was requested to start using the hub button/display UI.
+     */
+    PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_HUB_UI = 2,
+    /**
+     * The program was requested to start remotely, such as with an IDE.
+     */
+    PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_REMOTE = 3,
+} pbsys_main_program_start_request_type_t;
+
 /**
  * Main application program data information.
  */
@@ -41,14 +65,16 @@ typedef struct _pbsys_main_program_t {
      */
     pbio_pybricks_user_program_id_t id;
     /**
-     * Whether a request was made to start the program.
+     * Whether a request was made to start the program, and how.
      */
-    bool start_requested;
+    pbsys_main_program_start_request_type_t start_request_type;
 } pbsys_main_program_t;
 
 #if PBSYS_CONFIG_MAIN
 
-pbio_error_t pbsys_main_program_request_start(pbio_pybricks_user_program_id_t id);
+pbsys_main_program_start_request_type_t pbsys_main_program_get_start_request_type(void);
+
+pbio_error_t pbsys_main_program_request_start(pbio_pybricks_user_program_id_t id, pbsys_main_program_start_request_type_t start_request_type);
 
 /**
  * Validates the program that is being requested to start.

lib/pbio/sys/command.c

@@ -49,14 +49,14 @@ pbio_pybricks_error_t pbsys_command(const uint8_t *data, uint32_t size) {
             }
             // Use payload as program ID, otherwise use active user slot.
             return pbio_pybricks_error_from_pbio_error(
-                pbsys_main_program_request_start((size == 2 ? data[1] : pbsys_hmi_get_selected_program_slot())));
+                pbsys_main_program_request_start((size == 2 ? data[1] : pbsys_hmi_get_selected_program_slot()), PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_REMOTE));
         }
         #if PBSYS_CONFIG_FEATURE_BUILTIN_USER_PROGRAM_REPL
         case PBIO_PYBRICKS_COMMAND_START_REPL:
             // Deprecated. For backwards compatibility with Pybricks
             // Profile < v1.4.0, make it work anyway.
             return pbio_pybricks_error_from_pbio_error(
-                pbsys_main_program_request_start(PBIO_PYBRICKS_USER_PROGRAM_ID_REPL));
+                pbsys_main_program_request_start(PBIO_PYBRICKS_USER_PROGRAM_ID_REPL, PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_REMOTE));
         #endif // PBSYS_CONFIG_FEATURE_BUILTIN_USER_PROGRAM_REPL
 
         case PBIO_PYBRICKS_COMMAND_WRITE_USER_PROGRAM_META:

lib/pbio/sys/hmi.c

@@ -56,7 +56,7 @@ static PT_THREAD(update_program_run_button_wait_state(bool button_pressed)) {
 
         // If we made it through a full press and release, without the user
         // program running, then start the currently selected user program.
-        pbsys_main_program_request_start(selected_slot);
+        pbsys_main_program_request_start(selected_slot, PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_HUB_UI);
     }
 
     PT_END(pt);
@@ -152,7 +152,7 @@ static PT_THREAD(update_left_right_button_wait_state(bool left_button_pressed, b
         if (left_button_pressed && pbdrv_clock_get_ms() - first_press_time < 100) {
             selected_slot = previous_slot;
             pbsys_hub_light_matrix_update_program_slot();
-            pbsys_main_program_request_start(PBIO_PYBRICKS_USER_PROGRAM_ID_PORT_VIEW);
+            pbsys_main_program_request_start(PBIO_PYBRICKS_USER_PROGRAM_ID_PORT_VIEW, PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_HUB_UI);
         } else {
             // Successful switch. And UI was already updated.
             previous_slot = selected_slot;

lib/pbio/sys/main.c

@@ -20,8 +20,29 @@
 #include <pbsys/program_stop.h>
 #include <pbsys/bluetooth.h>
 
+// Singleton with information about the currently (or soon) active program.
 static pbsys_main_program_t program;
 
+/**
+ * Checks if a start request has been made for the main program.
+ *
+ * @param [in]  program A pointer to the main program structure.
+ * @returns     true if a start request has been made, false otherwise.
+ */
+static bool pbsys_main_program_start_requested() {
+    return program.start_request_type != PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_NONE;
+}
+
+/**
+ * Gets the type of start request for the main program.
+ *
+ * @param [in]  program A pointer to the main program structure.
+ * @returns     The type of start request.
+ */
+pbsys_main_program_start_request_type_t pbsys_main_program_get_start_request_type(void) {
+    return program.start_request_type;
+}
+
 /**
  * Requests to start the main user application program.
  *
@@ -31,10 +52,10 @@ static pbsys_main_program_t program;
  *              ::PBIO_ERROR_NOT_SUPPORTED if the program is not available.
  *              Otherwise ::PBIO_SUCCESS.
  */
-pbio_error_t pbsys_main_program_request_start(pbio_pybricks_user_program_id_t id) {
+pbio_error_t pbsys_main_program_request_start(pbio_pybricks_user_program_id_t id, pbsys_main_program_start_request_type_t start_request_type) {
 
     // Can't start new program if already running or new requested.
-    if (pbsys_status_test(PBIO_PYBRICKS_STATUS_USER_PROGRAM_RUNNING) || program.start_requested) {
+    if (pbsys_status_test(PBIO_PYBRICKS_STATUS_USER_PROGRAM_RUNNING) || pbsys_main_program_start_requested()) {
         return PBIO_ERROR_BUSY;
     }
 
@@ -49,7 +70,7 @@ pbio_error_t pbsys_main_program_request_start(pbio_pybricks_user_program_id_t id
         return err;
     }
 
-    program.start_requested = true;
+    program.start_request_type = start_request_type;
 
     return PBIO_SUCCESS;
 }
@@ -68,15 +89,15 @@ int main(int argc, char **argv) {
     while (!pbsys_status_test(PBIO_PYBRICKS_STATUS_SHUTDOWN_REQUEST)) {
 
         #if PBSYS_CONFIG_USER_PROGRAM_AUTO_START
-        pbsys_main_program_request_start(PBIO_PYBRICKS_USER_PROGRAM_ID_REPL);
+        pbsys_main_program_request_start(PBIO_PYBRICKS_USER_PROGRAM_ID_REPL, PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_BOOT);
         #endif
 
         // REVISIT: this can be long waiting, so we could do a more efficient
         // wait (i.e. __WFI() on embedded system)
         while (pbio_do_one_event()) {
         }
 
-        if (!program.start_requested) {
+        if (!pbsys_main_program_start_requested()) {
             continue;
         }
 
@@ -98,7 +119,7 @@ int main(int argc, char **argv) {
         pbsys_bluetooth_rx_set_callback(NULL);
         pbsys_program_stop_set_buttons(PBIO_BUTTON_CENTER);
         pbio_stop_all(true);
-        program.start_requested = false;
+        program.start_request_type = PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_NONE;
     }
 
     // Stop system processes and save user data before we shutdown.

pybricks/common/pb_type_system.c

@@ -9,6 +9,7 @@
 
 #include <pbdrv/bluetooth.h>
 #include <pbdrv/reset.h>
+#include <pbsys/main.h>
 #include <pbsys/program_stop.h>
 #include <pbsys/status.h>
 #include <pbsys/storage.h>
@@ -48,6 +49,7 @@ static mp_obj_t pb_type_System_info(void) {
         {MP_OBJ_NEW_QSTR(MP_QSTR_reset_reason), mp_obj_new_int(pbdrv_reset_get_reason())},
         #endif // PBDRV_CONFIG_RESET
         {MP_OBJ_NEW_QSTR(MP_QSTR_host_connected_ble), mp_obj_new_bool(pbsys_status_test(PBIO_PYBRICKS_STATUS_BLE_HOST_CONNECTED))},
+        {MP_OBJ_NEW_QSTR(MP_QSTR_program_start_type), mp_obj_new_int(pbsys_main_program_get_start_request_type())},
     };
     mp_obj_t info_dict = mp_obj_new_dict(MP_ARRAY_SIZE(info));