From af6965eefa1a958a1deebdd153e997aa387fc12f Mon Sep 17 00:00:00 2001
From: topjohnwu <topjohnwu@gmail.com>
Date: Mon, 26 Feb 2024 17:49:11 -0800
Subject: [PATCH] Update init logging implementation

Use less std::fs
---
 native/src/init/logging.rs | 60 ++++++++++++++++++--------------------
 1 file changed, 28 insertions(+), 32 deletions(-)

diff --git a/native/src/init/logging.rs b/native/src/init/logging.rs
index c907aa3ec..e38b915b0 100644
--- a/native/src/init/logging.rs
+++ b/native/src/init/logging.rs
@@ -1,58 +1,54 @@
-use std::fs;
 use std::fs::File;
 use std::io::{IoSlice, Write};
-use std::sync::OnceLock;
 
 use base::libc::{
-    close, makedev, mknod, open, syscall, unlink, SYS_dup3, O_CLOEXEC, O_RDWR, STDERR_FILENO,
-    STDIN_FILENO, STDOUT_FILENO, S_IFCHR,
+    makedev, mknod, syscall, SYS_dup3, O_CLOEXEC, O_RDWR, O_WRONLY, STDERR_FILENO, STDIN_FILENO,
+    STDOUT_FILENO, S_IFCHR,
 };
-use base::{cstr, exit_on_error, raw_cstr, LogLevel, Logger, Utf8CStr, LOGGER};
+use base::{cstr, exit_on_error, open_fd, raw_cstr, FsPath, LogLevel, Logger, Utf8CStr, LOGGER};
 
-static KMSG: OnceLock<File> = OnceLock::new();
+// SAFETY: magiskinit is single threaded
+static mut KMSG: Option<File> = None;
 
 pub fn setup_klog() {
-    // Shut down first 3 fds
     unsafe {
-        let mut fd = open(raw_cstr!("/dev/null"), O_RDWR | O_CLOEXEC);
-        if fd < 0 {
+        // Shut down first 3 fds
+        let mut fd = open_fd!(cstr!("/dev/null"), O_RDWR | O_CLOEXEC);
+        if fd.is_err() {
             mknod(raw_cstr!("/null"), S_IFCHR | 0o666, makedev(1, 3));
-            fd = open(raw_cstr!("/null"), O_RDWR | O_CLOEXEC);
-            fs::remove_file("/null").ok();
+            fd = open_fd!(cstr!("/null"), O_RDWR | O_CLOEXEC);
+            FsPath::from(cstr!("/null")).remove().ok();
+        }
+        if let Ok(ref fd) = fd {
+            syscall(SYS_dup3, fd, STDIN_FILENO, O_CLOEXEC);
+            syscall(SYS_dup3, fd, STDOUT_FILENO, O_CLOEXEC);
+            syscall(SYS_dup3, fd, STDERR_FILENO, O_CLOEXEC);
         }
 
-        syscall(SYS_dup3, fd, STDIN_FILENO, O_CLOEXEC);
-        syscall(SYS_dup3, fd, STDOUT_FILENO, O_CLOEXEC);
-        syscall(SYS_dup3, fd, STDERR_FILENO, O_CLOEXEC);
-        if fd > STDERR_FILENO {
-            close(fd);
-        }
-    }
-
-    if let Ok(kmsg) = File::options().write(true).open("/dev/kmsg") {
-        KMSG.set(kmsg).ok();
-    } else {
-        unsafe {
+        // Then open kmsg fd
+        let mut fd = open_fd!(cstr!("/dev/kmsg"), O_WRONLY | O_CLOEXEC);
+        if fd.is_err() {
             mknod(raw_cstr!("/kmsg"), S_IFCHR | 0o666, makedev(1, 11));
-            KMSG.set(File::options().write(true).open("/kmsg").unwrap())
-                .ok();
-            unlink(raw_cstr!("/kmsg"));
+            fd = open_fd!(cstr!("/kmsg"), O_WRONLY | O_CLOEXEC);
+            FsPath::from(cstr!("/kmsg")).remove().ok();
         }
+        KMSG = fd.map(|fd| fd.into()).ok();
     }
 
     // Disable kmsg rate limiting
-    if let Ok(mut rate) = File::options()
-        .write(true)
-        .open("/proc/sys/kernel/printk_devkmsg")
-    {
+    if let Ok(rate) = open_fd!(
+        cstr!("/proc/sys/kernel/printk_devkmsg"),
+        O_WRONLY | O_CLOEXEC
+    ) {
+        let mut rate = File::from(rate);
         writeln!(rate, "on").ok();
     }
 
     fn kmsg_log_write(_: LogLevel, msg: &Utf8CStr) {
-        if let Some(kmsg) = KMSG.get().as_mut() {
+        if let Some(kmsg) = unsafe { &mut KMSG } {
             let io1 = IoSlice::new("magiskinit: ".as_bytes());
             let io2 = IoSlice::new(msg.as_bytes());
-            kmsg.write_vectored(&[io1, io2]).ok();
+            let _ = kmsg.write_vectored(&[io1, io2]).ok();
         }
     }