v1.5.5

native/rust/src/modules/custom_font_hook.rs

@@ -1,31 +1,70 @@
-use std::{ffi::{CStr, CString}, fs};
+use std::{cell::Cell, ffi::{CStr, CString}};
 
 use nix::libc::{self, c_uint};
 
 use crate::{config, def_hook, dobby_hook_sym};
 
+thread_local! {
+    static FONT_REDIRECT_IN_PROGRESS: Cell<bool> = const { Cell::new(false) };
+}
+
+fn should_redirect_font(pathname: &str) -> bool {
+    let normalized = pathname.replace('\\', "/");
+    let file_name = normalized.rsplit('/').next().unwrap_or(&normalized).to_ascii_lowercase();
+    let is_font_file = file_name.ends_with(".ttf")
+        || file_name.ends_with(".ttc")
+        || file_name.ends_with(".otf");
+    let is_system_font_path = normalized.starts_with("/system/fonts/")
+        || normalized.starts_with("/product/fonts/")
+        || normalized.starts_with("/system_ext/fonts/")
+        || normalized.starts_with("/vendor/fonts/");
+
+    is_system_font_path && is_font_file && (
+        file_name.contains("emoji")
+            || file_name == "noto_color_emoji.ttf"
+            || file_name == "samsungcoloremoji.ttf"
+    )
+}
+
+fn open_custom_font_fd(flags: i32, mode: c_uint) -> Option<i32> {
+    let font_path = config::native_config().custom_emoji_font_path.clone()?;
+
+    match CString::new(font_path.clone()) {
+        Ok(c_font_path) => {
+            let fd = FONT_REDIRECT_IN_PROGRESS.with(|guard| {
+                let was_active = guard.replace(true);
+                let fd = unsafe { libc::openat(libc::AT_FDCWD, c_font_path.as_ptr() as *const u8, flags, mode) };
+                guard.set(was_active);
+                fd
+            });
+            if fd >= 0 {
+                debug!("redirected emoji font open to {}", font_path);
+                Some(fd)
+            } else {
+                debug!("failed to open custom emoji font path (fd={}): {}", fd, font_path);
+                None
+            }
+        }
+        Err(_) => {
+            warn!("custom emoji font path contains null byte, using fallback system font");
+            None
+        }
+    }
+}
+
 def_hook!(
     open_hook,
     i32,
     |path: *const u8, flags: i32, mode: c_uint| {
-        if let Ok(pathname) = CStr::from_ptr(path).to_str() {
-            if pathname == "/system/fonts/NotoColorEmoji.ttf"  {
-                if let Some(font_path) = config::native_config().custom_emoji_font_path {
-                    if fs::metadata(&font_path).is_ok() {
-                        match CString::new(font_path.clone()) {
-                            Ok(c_font_path) => {
-                                let fd = libc::openat(libc::AT_FDCWD, c_font_path.as_ptr() as *const u8, flags, mode);
-                                if fd >= 0 {
-                                    return fd;
-                                }
-                                warn!("failed to open custom emoji font path (fd={}): {}", fd, font_path);
-                            }
-                            Err(_) => {
-                                warn!("custom emoji font path contains null byte, using fallback system font");
-                            }
-                        }
-                    } else {
-                        warn!("custom emoji font path does not exist: {}", font_path);
+        if FONT_REDIRECT_IN_PROGRESS.with(|guard| guard.get()) {
+            return open_hook_original.unwrap()(path, flags, mode);
+        }
+
+        if !path.is_null() {
+            if let Ok(pathname) = CStr::from_ptr(path).to_str() {
+                if should_redirect_font(pathname) {
+                    if let Some(fd) = open_custom_font_fd(flags, mode) {
+                        return fd;
                     }
                 }
             }
@@ -35,7 +74,6 @@ def_hook!(
     }
 );
 
-
 pub fn init() {
     if config::native_config().custom_emoji_font_path.is_none() {
         return;