From 1fd7cd693a031bcfd799aad442cc3d6c10af7bde Mon Sep 17 00:00:00 2001
From: chenzw <[EMAIL REDACTED]>
Date: Wed, 4 Feb 2026 11:11:54 +0800
Subject: [PATCH] pass payload to state handler
---
src/joystick/hidapi/SDL_hidapi_gamesir.c | 116 +++++++++++------------
1 file changed, 56 insertions(+), 60 deletions(-)
diff --git a/src/joystick/hidapi/SDL_hidapi_gamesir.c b/src/joystick/hidapi/SDL_hidapi_gamesir.c
index d2dadf7eb3f3e..b0cfcb515702c 100644
--- a/src/joystick/hidapi/SDL_hidapi_gamesir.c
+++ b/src/joystick/hidapi/SDL_hidapi_gamesir.c
@@ -243,6 +243,7 @@ typedef struct {
Uint64 sensor_timestamp_step_ns;
float accelScale;
float gyroScale;
+ bool last_state_initialized;
Uint8 last_state[USB_PACKET_LENGTH];
SDL_hid_device *output_handle;
} SDL_DriverGamesir_Context;
@@ -433,6 +434,7 @@ static bool HIDAPI_DriverGameSir_OpenJoystick(SDL_HIDAPI_Device *device, SDL_Joy
}
SDL_zeroa(ctx->last_state);
+ ctx->last_state_initialized = false;
SendGameSirModeSwitch(device);
@@ -648,38 +650,16 @@ static void HIDAPI_DriverGameSir_HandleStatePacket(SDL_Joystick *joystick, SDL_D
return;
}
- int packet_size = size;
- const Uint8 *packet = data;
-
- // Check packet format: it may include a report ID (0x43) as the first byte
- // Actual packet format: 43 a1 c8 [button data...]
- // If the first byte is 0x43, the second is 0xA1 and the third is 0xC8, skip the report ID
- if (size >= 3 && packet[0] == 0x43 && packet[1] == GAMESIR_PACKET_HEADER_0 && packet[2] == GAMESIR_PACKET_HEADER_1_GAMEPAD) {
- // Packet contains a report ID; skip it for indexing and size checks
- packet_size = size - 1;
- packet = data + 1;
- } else if (size >= 2 && packet[0] == GAMESIR_PACKET_HEADER_0 && packet[1] == GAMESIR_PACKET_HEADER_1_GAMEPAD) {
- // Standard format: no report ID, header bytes directly
- packet_size = size;
- } else {
- // Packet format does not match; return immediately
- return;
- }
-
- const int header_size = 2;
- const int payload_size = packet_size - header_size;
- const Uint8 *payload = packet + header_size;
- const Uint8 *last = ctx->last_state + header_size;
-
- bool is_initial_packet = (ctx->last_state[0] == 0 && ctx->last_state[1] == 0 && ctx->last_state[2] == 0 && ctx->last_state[3] == 0);
+ const Uint8 *last = ctx->last_state;
+ bool is_initial_packet = !ctx->last_state_initialized;
const int min_payload_size = ctx->sensors_enabled ? 26 : 14;
- if (payload_size < min_payload_size) {
+ if (size < min_payload_size) {
return;
}
- if (last[0] != payload[0]) {
- Uint8 buttons = payload[0];
+ if (last[0] != data[0]) {
+ Uint8 buttons = data[0];
// BTN1: A B C X Y Z L1 R1
// Use bitwise operations to check whether each button is pressed
// buttons & BTN_A returns the value of BTN_A (if pressed) or 0 (if not pressed)
@@ -691,10 +671,10 @@ static void HIDAPI_DriverGameSir_HandleStatePacket(SDL_Joystick *joystick, SDL_D
SDL_SendJoystickButton(timestamp, joystick, SDL_GAMEPAD_BUTTON_RIGHT_SHOULDER, buttons & BTN_R1);
}
- if (last[1] != payload[1]) {
- Uint8 buttons = payload[1];
+ if (last[1] != data[1]) {
+ Uint8 buttons = data[1];
// BTN2: L2 R2 SELECT START HOME L3 R3 CAPTURE
- // Note: L2/R2 appear as digital buttons in payload[1], but their actual analog values are in payload[12]/payload[13].
+ // Note: L2/R2 appear as digital buttons in data[1], but their actual analog values are in data[12]/data[13].
// Only handle the other buttons here; trigger analog values are processed later in the code.
SDL_SendJoystickButton(timestamp, joystick, SDL_GAMEPAD_BUTTON_BACK, buttons & BTN_SELECT);
SDL_SendJoystickButton(timestamp, joystick, SDL_GAMEPAD_BUTTON_START, buttons & BTN_START);
@@ -704,8 +684,8 @@ static void HIDAPI_DriverGameSir_HandleStatePacket(SDL_Joystick *joystick, SDL_D
SDL_SendJoystickButton(timestamp, joystick, SDL_GAMEPAD_BUTTON_MISC1, buttons & BTN_CAPTURE);
}
- if (last[2] != payload[2]) {
- Uint8 buttons = payload[2];
+ if (last[2] != data[2]) {
+ Uint8 buttons = data[2];
// BTN3: UP DOWN LEFT RIGHT M MUTE L4 R4
// Handle the directional pad (D-pad)
Uint8 hat = SDL_HAT_CENTERED;
@@ -738,8 +718,8 @@ static void HIDAPI_DriverGameSir_HandleStatePacket(SDL_Joystick *joystick, SDL_D
SDL_SendJoystickButton(timestamp, joystick, SDL_GAMEPAD_BUTTON_MISC2, buttons & BTN_MUTE);
}
- if (last[3] != payload[3]) {
- Uint8 buttons = payload[3];
+ if (last[3] != data[3]) {
+ Uint8 buttons = data[3];
// BTN4: L5 R5 L6 R6 L7 R7 L8 R8
SDL_SendJoystickButton(timestamp, joystick, SDL_GAMEPAD_BUTTON_LEFT_PADDLE2, buttons & BTN_L5);
SDL_SendJoystickButton(timestamp, joystick, SDL_GAMEPAD_BUTTON_RIGHT_PADDLE2, buttons & BTN_R5);
@@ -760,10 +740,10 @@ static void HIDAPI_DriverGameSir_HandleStatePacket(SDL_Joystick *joystick, SDL_D
// Left stick: payload bytes 4-7 (16-bit values)
// Bytes 4-5: X axis (Hi/Low combined into a signed 16-bit value, e.g. 0x7df6)
// Bytes 6-7: Y axis (Hi/Low combined into a signed 16-bit value)
- if (payload_size >= 8) {
- // Combine bytes 4-5 into a 16-bit value, e.g.: payload[4]=0x7d, payload[5]=0xf6 -> 0x7df6
- Uint16 raw_x_unsigned = ((Uint16)payload[4] << 8) | payload[5];
- Uint16 raw_y_unsigned = ((Uint16)payload[6] << 8) | payload[7];
+ if (size >= 8) {
+ // Combine bytes 4-5 into a 16-bit value, e.g.: data[4]=0x7d, data[5]=0xf6 -> 0x7df6
+ Uint16 raw_x_unsigned = ((Uint16)data[4] << 8) | data[5];
+ Uint16 raw_y_unsigned = ((Uint16)data[6] << 8) | data[7];
// Interpret the unsigned 16-bit value as a signed 16-bit value
Sint16 raw_x = (Sint16)raw_x_unsigned;
@@ -802,11 +782,11 @@ static void HIDAPI_DriverGameSir_HandleStatePacket(SDL_Joystick *joystick, SDL_D
// Right stick: payload bytes 8-11 (16-bit values)
// Bytes 8-9: X axis (Hi/Low combined into a signed 16-bit value)
// Bytes 10-11: Y axis (Hi/Low combined into a signed 16-bit value)
- if (payload_size >= 12) {
+ if (size >= 12) {
// Combine bytes 8-9 into a 16-bit value
- Uint16 raw_x_unsigned = ((Uint16)payload[8] << 8) | payload[9];
+ Uint16 raw_x_unsigned = ((Uint16)data[8] << 8) | data[9];
// Combine bytes 10-11 into a 16-bit value
- Uint16 raw_y_unsigned = ((Uint16)payload[10] << 8) | payload[11];
+ Uint16 raw_y_unsigned = ((Uint16)data[10] << 8) | data[11];
// Interpret the unsigned 16-bit value as a signed 16-bit value
Sint16 raw_x = (Sint16)raw_x_unsigned;
@@ -846,18 +826,18 @@ static void HIDAPI_DriverGameSir_HandleStatePacket(SDL_Joystick *joystick, SDL_D
// R2 (payload byte 13) - analog right trigger 0-255, 0 = released, 255 = pressed
// SDL range: 0-32767 (0 = released, 32767 = fully pressed)
// Linear mapping: 0-255 -> 0-32767
- if (last[12] != payload[12]) {
- axis = (Sint16)(((int)payload[12] * 255) - 32767);
+ if (last[12] != data[12]) {
+ axis = (Sint16)(((int)data[12] * 255) - 32767);
SDL_SendJoystickAxis(timestamp, joystick, SDL_GAMEPAD_AXIS_LEFT_TRIGGER, axis);
}
- if (last[13] != payload[13]) {
- axis = (Sint16)(((int)payload[13] * 255) - 32767);
+ if (last[13] != data[13]) {
+ axis = (Sint16)(((int)data[13] * 255) - 32767);
SDL_SendJoystickAxis(timestamp, joystick, SDL_GAMEPAD_AXIS_RIGHT_TRIGGER, axis);
}
}
- if (ctx->sensors_enabled && !is_initial_packet && payload_size >= 26) {
+ if (ctx->sensors_enabled && !is_initial_packet && size >= 26) {
Uint64 sensor_timestamp;
float values[3];
@@ -868,9 +848,9 @@ static void HIDAPI_DriverGameSir_HandleStatePacket(SDL_Joystick *joystick, SDL_D
// Bytes 14-15: Acc X (Hi/Low combined into a signed 16-bit value)
// Bytes 16-17: Acc Y (Hi/Low combined into a signed 16-bit value)
// Bytes 18-19: Acc Z (Hi/Low combined into a signed 16-bit value)
- Uint16 acc_x_unsigned = ((Uint16)payload[14] << 8) | payload[15];
- Uint16 acc_y_unsigned = ((Uint16)payload[16] << 8) | payload[17];
- Uint16 acc_z_unsigned = ((Uint16)payload[18] << 8) | payload[19];
+ Uint16 acc_x_unsigned = ((Uint16)data[14] << 8) | data[15];
+ Uint16 acc_y_unsigned = ((Uint16)data[16] << 8) | data[17];
+ Uint16 acc_z_unsigned = ((Uint16)data[18] << 8) | data[19];
// Convert the unsigned 16-bit values to signed 16-bit values
Sint16 acc_x = (Sint16)acc_x_unsigned;
@@ -888,9 +868,9 @@ static void HIDAPI_DriverGameSir_HandleStatePacket(SDL_Joystick *joystick, SDL_D
// Bytes 20-21: Gyro X (Hi/Low combined into a signed 16-bit value)
// Bytes 22-23: Gyro Y (Hi/Low combined into a signed 16-bit value)
// Bytes 24-25: Gyro Z (Hi/Low combined into a signed 16-bit value)
- Uint16 gyro_x_unsigned = ((Uint16)payload[20] << 8) | payload[21];
- Uint16 gyro_y_unsigned = ((Uint16)payload[22] << 8) | payload[23];
- Uint16 gyro_z_unsigned = ((Uint16)payload[24] << 8) | payload[25];
+ Uint16 gyro_x_unsigned = ((Uint16)data[20] << 8) | data[21];
+ Uint16 gyro_y_unsigned = ((Uint16)data[22] << 8) | data[23];
+ Uint16 gyro_z_unsigned = ((Uint16)data[24] << 8) | data[25];
// Convert the unsigned 16-bit values to signed 16-bit values
Sint16 gyro_x = (Sint16)gyro_x_unsigned;
@@ -907,12 +887,12 @@ static void HIDAPI_DriverGameSir_HandleStatePacket(SDL_Joystick *joystick, SDL_D
values[2] = (float)gyro_z * ctx->gyroScale; // Gyro Z (Roll)
SDL_SendJoystickSensor(timestamp, joystick, SDL_SENSOR_GYRO, sensor_timestamp, values, 3);
}
- if (payload_size >= 32) {
- Uint16 l_touchpad_x = ((Uint16)payload[26] << 4) | ((payload[27] >> 4) & 0x0F);
- Uint16 l_touchpad_y = ((Uint16)(payload[27] & 0x0F) << 8) | payload[28];
+ if (size >= 32) {
+ Uint16 l_touchpad_x = ((Uint16)data[26] << 4) | ((data[27] >> 4) & 0x0F);
+ Uint16 l_touchpad_y = ((Uint16)(data[27] & 0x0F) << 8) | data[28];
- Uint16 r_touchpad_x = ((Uint16)payload[29] << 4) | ((payload[30] >> 4) & 0x0F);
- Uint16 r_touchpad_y = ((Uint16)(payload[30] & 0x0F) << 8) | payload[31];
+ Uint16 r_touchpad_x = ((Uint16)data[29] << 4) | ((data[30] >> 4) & 0x0F);
+ Uint16 r_touchpad_y = ((Uint16)(data[30] & 0x0F) << 8) | data[31];
(void)l_touchpad_x;
(void)l_touchpad_y;
@@ -920,7 +900,8 @@ static void HIDAPI_DriverGameSir_HandleStatePacket(SDL_Joystick *joystick, SDL_D
(void)r_touchpad_y;
}
- SDL_memcpy(ctx->last_state, packet, SDL_min(packet_size, sizeof(ctx->last_state)));
+ SDL_memcpy(ctx->last_state, data, SDL_min(size, sizeof(ctx->last_state)));
+ ctx->last_state_initialized = true;
}
@@ -954,8 +935,23 @@ static bool HIDAPI_DriverGameSir_UpdateDevice(SDL_HIDAPI_Device *device)
while ((size = SDL_hid_read_timeout(handle, data, sizeof(data), 0)) > 0) {
if (joystick) {
- // Uncomment to handle the packet
- HIDAPI_DriverGameSir_HandleStatePacket(joystick, ctx, data, size);
+ Uint8 *payload = NULL;
+ int payload_size = 0;
+
+ // Check packet format: it may include a report ID (0x43) as the first byte
+ // Actual packet format: 43 a1 c8 [button data...]
+ // If the first byte is 0x43, the second is 0xA1 and the third is 0xC8, skip the report ID
+ if (size >= 3 && data[0] == 0x43 && data[1] == GAMESIR_PACKET_HEADER_0 && data[2] == GAMESIR_PACKET_HEADER_1_GAMEPAD) {
+ payload = data + 3;
+ payload_size = size - 3;
+ } else if (size >= 2 && data[0] == GAMESIR_PACKET_HEADER_0 && data[1] == GAMESIR_PACKET_HEADER_1_GAMEPAD) {
+ payload = data + 2;
+ payload_size = size - 2;
+ }
+
+ if (payload) {
+ HIDAPI_DriverGameSir_HandleStatePacket(joystick, ctx, payload, payload_size);
+ }
}
}