TCP input injection for port 2 (set_input/press/clear_input port=2)

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
(cherry picked from commit 66cc81fe63)

runtime/include/debug_server.h

@@ -198,6 +198,8 @@ void debug_server_check_watchpoints(void);
 /* Returns >= 0 if the debug server wants to override pad input,
  * -1 if no override is active. Value is PS1 16-bit button mask. */
 int debug_server_get_input_override(void);
+/* Port-2 override word (set_input/press "port":2), or -1. */
+int debug_server_get_input_override_port2(void);
 
 /* Optional analog-stick override set alongside set_input (lx/ly/rx/ry,
  * 0..255, 0x80 = centre). Returns 1 and fills st[lx,ly,rx,ry] when armed,

runtime/src/debug_server.c

@@ -286,6 +286,10 @@ static uint64_t s_dirty_break_hits = 0;
 /* ---- Input override ---- */
 static int s_input_override = -1;
 static int s_input_frames   = 0;
+/* Port 2 (set_input / press / clear_input "port":2): digital buttons only,
+ * for driving two-player modes headless. */
+static int s_input_override_p2 = -1;
+static int s_input_frames_p2   = 0;
 /* Optional analog-stick override (set_input lx/ly/rx/ry, 0..255, 0x80 =
  * centre). Lets injected input drive analog-mode movement; consumed by the
  * pad sampler alongside the button word. */
@@ -8004,6 +8008,12 @@ static void handle_set_input(int id, const char *json)
     if (pad_type < -1 || pad_type > 2) {
         send_err(id, "pad_type must be -1 (automatic), 0, 1, or 2"); return;
     }
+    if (json_get_int(json, "port", 1) == 2) {
+        s_input_override_p2 = (int)(hex_to_u32(val_str) & 0xFFFFu);
+        s_input_frames_p2 = 0;
+        send_ok(id);
+        return;
+    }
     s_pad_type_override = pad_type;
     s_input_override = (int)hex_to_u32(val_str);
     s_input_frames = 0;
@@ -8044,6 +8054,12 @@ static void handle_press(int id, const char *json)
     if (pad_type < -1 || pad_type > 2) {
         send_err(id, "pad_type must be -1 (automatic), 0, 1, or 2"); return;
     }
+    if (json_get_int(json, "port", 1) == 2) {
+        s_input_override_p2 = buttons & 0xFFFF;
+        s_input_frames_p2   = frames;
+        send_ok(id);
+        return;
+    }
     s_pad_type_override = pad_type;
     s_input_override = buttons;
     s_input_frames   = frames;
@@ -8095,6 +8111,7 @@ static void handle_pad_status(int id, const char *json)
              "\"slot1\":{\"buttons\":\"0x%04X\",\"connected\":%s,\"analog\":%s,\"type\":%d,\"sticks\":[%u,%u,%u,%u],"
              "\"negcon\":[%u,%u,%u],\"mode_locked\":%s},"
              "\"override\":%d,\"override_frames\":%d,\"override_pad_type\":%d,"
+             "\"override_p2\":%d,\"override_p2_frames\":%d,"
              "\"override_axes\":[%u,%u,%u,%u],\"override_axes_valid\":%s,"
              "\"host_layer\":%s,\"host_buttons\":\"0x%04X\",\"host_axes\":[%u,%u,%u,%u],"
              "\"host_lt\":%u,\"host_rt\":%u}\n",
@@ -8108,6 +8125,7 @@ static void handle_pad_status(int id, const char *json)
              sticks1[0], sticks1[1], sticks1[2], sticks1[3],
              neg1[0], neg1[1], neg1[2], sio_get_pad_mode_locked(1) ? "true" : "false",
              s_input_override, s_input_frames, s_pad_type_override,
+             s_input_override_p2, s_input_frames_p2,
              s_axis_st[0], s_axis_st[1], s_axis_st[2], s_axis_st[3],
              s_axis_override ? "true" : "false",
              s_host_layer ? "true" : "false", s_host_buttons,
@@ -8117,7 +8135,12 @@ static void handle_pad_status(int id, const char *json)
 
 static void handle_clear_input(int id, const char *json)
 {
-    (void)json;
+    const int port = json_get_int(json, "port", 0);   /* 0 = both */
+    if (port == 0 || port == 2) {
+        s_input_override_p2 = -1;
+        s_input_frames_p2 = 0;
+    }
+    if (port == 2) { send_ok(id); return; }
     s_input_route_active = 0;
     s_input_route_index = 0;
     s_input_route_remaining = 0;
@@ -16718,6 +16741,16 @@ int debug_server_get_input_override(void)
     return current;
 }
 
+int debug_server_get_input_override_port2(void)
+{
+    int current = s_input_override_p2;
+    if (s_input_override_p2 >= 0 && s_input_frames_p2 > 0) {
+        if (--s_input_frames_p2 == 0)
+            s_input_override_p2 = -1;
+    }
+    return current;
+}
+
 int debug_server_get_axis_override(unsigned char st[4])
 {
     if (!s_axis_override) return 0;

runtime/src/main.cpp

@@ -6878,6 +6878,18 @@ static PadExtHooks pad_ext_main_hooks(void) {
     return h;
 }
 
+/* TCP port-2 injection (set_input/press "port":2): a digital pad plugged
+ * into port 2 for as long as a test drives it, so headless runs can reach and
+ * play two-player modes. Applied after the normal sampling so it wins. */
+static void apply_input_override_port2(int override_word) {
+    if (override_word < 0) return;
+    if (!sio_get_pad_connected(1)) {
+        sio_set_pad_connected(1, 1);
+        sio_set_pad_analog(1, 0, 0x80, 0x80, 0x80, 0x80);
+    }
+    sio_set_pad_state_slot(1, (uint16_t)override_word);
+}
+
 static void sample_pad_into_sio(int override) {
     /* Selfcheck fighter mash owns P1 when enabled (headless-safe). */
     if (override < 0) {
@@ -8098,12 +8110,14 @@ static NetplayVblankEpilogue sdl_vblank_present_body(void) {
 
     /* Check debug server input override. */
     int override = debug_server_get_input_override();
+    int override_p2 = debug_server_get_input_override_port2();
 #else
     /* Production: skip debug server. Still need to advance frame counter
      * locally so anything else that reads it continues to work. */
     extern uint64_t s_frame_count;
     s_frame_count++;
     int override = -1;
+    int override_p2 = -1;
 #endif
 
     psx_local_mouse_begin(sdl_window, local_mouse_live(override));
@@ -8299,6 +8313,7 @@ static NetplayVblankEpilogue sdl_vblank_present_body(void) {
                 sample_headless_pad_into_sio(override);
             else
                 sample_pad_into_sio(override);
+            apply_input_override_port2(override_p2);
         }
         /* Offline vblank boundary: record/replay/compare (PSX_RB_SELFCHECK).
          * Defer opening a window while multitap arming is still pending —
@@ -8629,6 +8644,7 @@ static NetplayVblankEpilogue sdl_vblank_present_body(void) {
                 SDL_PumpEvents(); // retain native timing when no policy exists
             }
             sample_pad_into_sio(override);
+            apply_input_override_port2(override_p2);
             latency_ring_restamp_input();
         }
     }