From 7be9a1aef640f0976cc1890eac1d9675b3a37e33 Mon Sep 17 00:00:00 2001
From: Christine Dodrill <me@christine.website>
Date: Fri, 8 May 2020 16:59:08 -0400
Subject: [PATCH] implement gamebridge in the game code

---
 src/pc/configfile.c                        |  2 +
 src/pc/configfile.h                        |  1 +
 src/pc/controller/controller_entry_point.c |  2 +
 src/pc/controller/controller_gamebridge.c  | 69 ++++++++++++++++++++++
 src/pc/controller/controller_gamebridge.h  |  8 +++
 5 files changed, 82 insertions(+)
 create mode 100644 src/pc/controller/controller_gamebridge.c
 create mode 100644 src/pc/controller/controller_gamebridge.h

diff --git a/src/pc/configfile.c b/src/pc/configfile.c
index 10ff1e6..b8b1b4b 100644
--- a/src/pc/configfile.c
+++ b/src/pc/configfile.c
@@ -29,6 +29,7 @@ struct ConfigOption {
 /*
  *Config options and default values
  */
+bool configGameBridge            = false;
 bool configFullscreen            = false;
 // Keyboard mappings (scancode values)
 unsigned int configKeyA          = 0x26;
@@ -47,6 +48,7 @@ unsigned int configKeyStickRight = 0x20;
 
 
 static const struct ConfigOption options[] = {
+    {.name = "gamebridge",     .type = CONFIG_TYPE_BOOL, .boolValue = &configGameBridge},
     {.name = "fullscreen",     .type = CONFIG_TYPE_BOOL, .boolValue = &configFullscreen},
     {.name = "key_a",          .type = CONFIG_TYPE_UINT, .uintValue = &configKeyA},
     {.name = "key_b",          .type = CONFIG_TYPE_UINT, .uintValue = &configKeyB},
diff --git a/src/pc/configfile.h b/src/pc/configfile.h
index ae9070b..7e55613 100644
--- a/src/pc/configfile.h
+++ b/src/pc/configfile.h
@@ -1,6 +1,7 @@
 #ifndef CONFIGFILE_H
 #define CONFIGFILE_H
 
+extern bool         configGameBridge;
 extern bool         configFullscreen;
 extern unsigned int configKeyA;
 extern unsigned int configKeyB;
diff --git a/src/pc/controller/controller_entry_point.c b/src/pc/controller/controller_entry_point.c
index faf91f5..be8e773 100644
--- a/src/pc/controller/controller_entry_point.c
+++ b/src/pc/controller/controller_entry_point.c
@@ -5,11 +5,13 @@
 #include "controller_keyboard.h"
 
 #include "controller_sdl.h"
+#include "controller_gamebridge.h"
 
 static struct ControllerAPI *controller_implementations[] = {
     &controller_recorded_tas,
     &controller_sdl,
     &controller_keyboard,
+    &controller_gamebridge,
 };
 
 s32 osContInit(OSMesgQueue *mq, u8 *controllerBits, OSContStatus *status) {
diff --git a/src/pc/controller/controller_gamebridge.c b/src/pc/controller/controller_gamebridge.c
new file mode 100644
index 0000000..222dfe4
--- /dev/null
+++ b/src/pc/controller/controller_gamebridge.c
@@ -0,0 +1,69 @@
+#include <ctype.h>
+#include <string.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <ultra64.h>
+#include <assert.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include "controller_api.h"
+#include "../configfile.h"
+
+static FILE *vblank;
+static FILE *input;
+
+#define vblank_fname "vblank"
+#define input_fname "input"
+
+static void gamebridge_init(void) {
+    if (!configGameBridge) {
+        return;
+    }
+
+    unlink(vblank_fname);
+    unlink(input_fname);
+
+    int result;
+
+    result = mkfifo(vblank_fname, S_IRUSR|S_IWUSR);
+    if (result < 0) {
+        perror("mkfifo "vblank_fname);
+        assert(result < 0);
+    }
+
+    result = mkfifo(input_fname, S_IRUSR| S_IWUSR);
+    if (result < 0) {
+       perror("mkfifo "input_fname);
+       assert(result < 0);
+    }
+
+    vblank = fopen(vblank_fname, "w");
+    input = fopen(input_fname, "rb");
+    assert(vblank);
+    assert(input);
+
+    setvbuf(vblank, NULL, _IONBF, 0);
+    setvbuf(input, NULL, _IONBF, 0);
+}
+
+static void gamebridge_read(OSContPad *pad) {
+    if (!configGameBridge) {
+        return;
+    }
+
+    char* ok = "OK\n";
+    fwrite(ok, 1, sizeof(ok), vblank);
+    uint8_t bytes[4] = {0};
+    fread(bytes, 1, 4, input);
+    pad->button = (bytes[0] << 8) | bytes[1];
+    pad->stick_x = bytes[2];
+    pad->stick_y = bytes[3];
+}
+
+struct ControllerAPI controller_gamebridge = {
+    gamebridge_init,
+    gamebridge_read
+};
diff --git a/src/pc/controller/controller_gamebridge.h b/src/pc/controller/controller_gamebridge.h
new file mode 100644
index 0000000..cae2a4c
--- /dev/null
+++ b/src/pc/controller/controller_gamebridge.h
@@ -0,0 +1,8 @@
+#ifndef CONTROLLER_GAMEBRIDGE_H
+#define CONTROLLER_GAMEBRIDGE_H
+
+#include "controller_api.h"
+
+extern struct ControllerAPI controller_gamebridge;
+
+#endif