LG8n: Introduce shirayuki-dt2w service as a helper for DT2W service app

* The code can use some improvements

Signed-off-by: Shirayuki39 <lorddemecrius83@proton.me>

dt2w/Android.bp

@@ -30,7 +30,8 @@ android_app {
     },
 
     required: [
-        "privapp-permissions_co.potatoproject.dt2w.MT6789"
+        "privapp-permissions_co.potatoproject.dt2w.MT6789",
+        "shirayuki-dt2w"
     ]
 }
 
@@ -40,3 +41,11 @@ prebuilt_etc {
     src: "privapp-permissions_co.potatoproject.dt2w.MT6789.xml",
     filename_from_src: true,
 }
+
+cc_binary {
+    name: "shirayuki-dt2w",
+    srcs: [
+        "shirayuki-dt2w",
+    ],
+    vendor: true
+}

dt2w/shirayuki-dt2w.c

@@ -0,0 +1,70 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+
+#define GESTURE_FUNCTION_PATH "/proc/gesture_function"
+#define GESTURE_STATE_PATH "/proc/gesture_state"
+#define DT2W_STATE_PROP "persist.sys.MT6789.dt2w"
+
+// me noob sar
+
+// sounds like a great idea, with the best of intentions
+
+int main() {
+    FILE *fp, *fpState;
+    char cmd[100];
+    char buffer[20];
+    char stateBuffer[20];
+
+    // Wait until we finish boot
+    sprintf(cmd, "getprop sys.boot_completed");
+    while (system(cmd) != 0); // Assuming 'getprop' returns 0 when boot is completed
+
+    // Main loop to continuously monitor and adjust gesture function
+    while (1) {
+        sprintf(cmd, "getprop %s", DT2W_STATE_PROP);
+        fp = popen(cmd, "r");
+        if (fp == NULL) {
+            printf("prop not found\n");
+            exit(1);
+        }
+
+        fgets(buffer, sizeof(buffer)-1, fp);
+        pclose(fp);
+
+        // Remove trailing newline character, just so it's clean
+        buffer[strcspn(buffer, "\n")] = 0;
+
+        // see if gesture_state nude already has the value we want
+        sprintf(cmd, "awk '/cc:/ {print $2}' %s", GESTURE_STATE_PATH);
+        fpState = popen(cmd, "r");
+        if (fpState != NULL) {
+            fgets(stateBuffer, sizeof(stateBuffer)-1, fpState);
+            pclose(fpState);
+
+            // Remove trailing newline character
+            stateBuffer[strcspn(stateBuffer, "\n")] = 0;
+
+            if ((strcmp(buffer, "0") == 0 && strcmp(stateBuffer, "cc:0") != 0) ||
+                (strcmp(buffer, "1") == 0 && strcmp(stateBuffer, "cc:1") != 0)) {
+                // it doesn't have the value we want, go write
+                fp = fopen(GESTURE_FUNCTION_PATH, "w");
+            if (fp != NULL) {
+                if (strcmp(buffer, "0") == 0) {
+                    fputs("cc2", fp);
+                } else if (strcmp(buffer, "1") == 0) {
+                    fputs("cc1", fp);
+                }
+                fclose(fp);
+            }
+                }
+        } else {
+            printf("Failed to read gesture state\n");
+        }
+
+        sleep(1); // Sleep for 1 second before checking again
+    }
+
+    return 0;
+}

rootdir/etc/init/hw/init.project.rc

@@ -102,3 +102,6 @@ on property:sys.boot_completed=1
     write /sys/kernel/tracing/instances/mmstat/events/mmstat/enable 1
     write /sys/kernel/tracing/instances/mmstat/tracing_on 1
 
+# Shirayuki-DT2W Helper Service
+on property:sys.boot_completed=1
+   exec - root -- /vendor/bin/shirayuki-dt2w