homekit_service_by_type Causing Panic (Load Prohibited)

[mriksman]

Another issue I am having after the update. The code used to work.

When I change the value (brightness) on Home App, the callback function is called

void state_change_on_callback(homekit_characteristic_t *_ch, homekit_value_t value, void *context) {
    ESP_LOGI(TAG, "%s", _ch->description);
    homekit_service_t *light_service     = homekit_service_by_type(_ch->service->accessory, HOMEKIT_SERVICE_LIGHTBULB);
    homekit_characteristic_t *brightness = homekit_service_characteristic_by_type(light_service, HOMEKIT_CHARACTERISTIC_BRIGHTNESS);

It then panics at homekit_service_t *light_service = homekit_service_by_type(_ch->service->accessory, HOMEKIT_SERVICE_LIGHTBULB);

>>> HomeKit: [Client 2] Update Characteristics
>>> homekit_server_on_update_characteristics: Free heap: 158852
>>> homekit_server_on_update_characteristics: [Client 2] Processing element {
        "aid":  1,
        "iid":  11,
        "value":        70
}
>>> HomeKit: [Client 2] Updating characteristic 1.11 ("Brightness") with integer 70
>>> homekit_characteristic_notify: Got characteristic 1.11 change event
I (59161) main: Brightness
Guru Meditation Error: Core  0 panic'ed (LoadProhibited). Exception was unhandled.

Core  0 register dump:
PC      : 0x400d8e94  PS      : 0x00060530  A0      : 0x800e0b2d  A1      : 0x3ffd2df0  
--- 0x400d8e94: state_change_on_callback at /home/mriksman/Projects/esp32_homekit_animation/main/main.c:65

A2      : 0x3ffcf2c8  A3      : 0x00000000  A4      : 0x00000014  A5      : 0x00000000  
A6      : 0x00000046  A7      : 0x00000000  A8      : 0x00000000  A9      : 0x3ffd2da0  
A10     : 0x00000003  A11     : 0x3f403750  A12     : 0x3f403734  A13     : 0x0000e719  
A14     : 0x3f402294  A15     : 0x3ffcf35d  SAR     : 0x00000004  EXCCAUSE: 0x0000001c  
EXCVADDR: 0x00000000  LBEG    : 0x400014fd  LEND    : 0x4000150d  LCOUNT  : 0xfffffffd  
--- 0x400014fd: strlen in ROM
0x4000150d: strlen in ROM



Backtrace: 0x400d8e91:0x3ffd2df0 0x400e0b2a:0x3ffd2e40 0x400e1488:0x3ffd2e80 0x400e165a:0x3ffd2ef0 0x400e2fdd:0x3ffd2f30 0x40100e67:0x3ffd2f50 0x400df2ed:0x3ffd2fa0 0x400e1ae3:0x3ffd2fd0 0x400e3159:0x3ffd3020 0x4008b311:0x3ffd30e0
--- 0x400d8e91: state_change_on_callback at /home/mriksman/Projects/esp32_homekit_animation/main/main.c:65
0x400e0b2a: homekit_characteristic_notify at /home/mriksman/Projects/esp32_homekit_animation/components/homekit/src/server.c:3870
0x400e1488: process_characteristics_update at /home/mriksman/Projects/esp32_homekit_animation/components/homekit/src/server.c:3065
0x400e165a: homekit_server_on_update_characteristics at /home/mriksman/Projects/esp32_homekit_animation/components/homekit/src/server.c:3110
0x400e2fdd: homekit_server_on_message_complete at /home/mriksman/Projects/esp32_homekit_animation/components/homekit/src/server.c:3604
0x40100e67: http_parser_execute at /home/mriksman/Projects/esp32_homekit_animation/components/http-parser/http-parser/http_parser.c:1918 (discriminator 3)
0x400df2ed: homekit_client_process at /home/mriksman/Projects/esp32_homekit_animation/components/homekit/src/server.c:3702

My code is here
https://github.com/mriksman/esp32_homekit_animations

[mriksman]

I tried uncommenting a piece of code in my other program https://github.com/mriksman/esp32_homekit_light_switch. It too fails.

Line 625

            homekit_service_t *acc_service = homekit_service_by_type(light->service->accessory, HOMEKIT_SERVICE_ACCESSORY_INFORMATION);
            homekit_characteristic_t *acc_service_manufacture  = homekit_service_characteristic_by_type(acc_service, HOMEKIT_CHARACTERISTIC_MANUFACTURER);
            ESP_LOGE(TAG, "Button Press ***** Manufacturer NAME char %s", acc_service_manufacture->value.string_value ); 

Guru Meditation Error: Core  0 panic'ed (Load access fault). Exception was unhandled.

Core  0 register dump:
MEPC    : 0x420104b4  RA      : 0x4200adba  SP      : 0x3fca3580  GP      : 0x3fc94400  
--- 0x420104b4: homekit_service_by_type at /home/mriksman/Projects/esp32_homekit_light_switch_v5/components/homekit/src/server.c:594
0x4200adba: main_event_handler at /home/mriksman/Projects/esp32_homekit_light_switch_v5/main/main.c:626

TP      : 0x3fca3810  T0      : 0x000a6d30  T1      : 0x00000065  T2      : 0x5b1b4555  
S0/FP   : 0x3fca3ac0  S1      : 0x3fca2338  A0      : 0x00000000  A1      : 0x3c0f5540  
A2      : 0xfc000000  A3      : 0x00000020  A4      : 0x00000020  A5      : 0x3fcb3598  
A6      : 0x4200aa5e  A7      : 0x00000076  S2      : 0x3c0f5540  S3      : 0x00000025  
--- 0x4200aa5e: main_event_handler at /home/mriksman/Projects/esp32_homekit_light_switch_v5/main/main.c:521

S4      : 0xffffffff  S5      : 0x00000000  S6      : 0xffffffff  S7      : 0x3fcb0784  
S8      : 0x00000000  S9      : 0x00000000  S10     : 0x00000000  S11     : 0x00000000  
T3      : 0x0000000a  T4      : 0x00000000  T5      : 0x00000000  T6      : 0x00000000  
MSTATUS : 0x00001881  MTVEC   : 0x40380001  MCAUSE  : 0x00000005  MTVAL   : 0x0000000c  
--- 0x40380001: _vector_table at /home/mriksman/esp/v5.3.1/esp-idf/components/riscv/vectors_intc.S:54

[mriksman]

Found why it's happening. Originally, the function homekit_accessories_init() was in accessories.c and it would create the linking in services->accessory and characteristics->service. The important lines are

for (homekit_service_t **service_it = accessory->services; *service_it; service_it++) {
    homekit_service_t *service = *service_it;
    service->accessory = accessory;
    for (homekit_characteristic_t **ch_it = service->characteristics; *ch_it; ch_it++) {
        homekit_characteristic_t *ch = *ch_it;
        ch->service = service;
    }
}

In the new version, homekit_accessories_init() is in server.c and it no longer sets these back-pointers.

[mriksman]

I've created pull request #220. But I am no programmer, so it's worth a proper review!