Setup logging infra in the Rust side

native/jni/base/compat/fortify.hpp

@@ -6,7 +6,7 @@
 
 #undef _FORTIFY_SOURCE
 
-extern int __vloge(const char* fmt, va_list ap);
+extern void __vloge(const char* fmt, va_list ap);
 
 static inline __noreturn __printflike(1, 2) void __fortify_fatal(const char* fmt, ...) {
     va_list args;

native/jni/base/include/base.hpp

@@ -5,3 +5,4 @@
 #include "../files.hpp"
 #include "../misc.hpp"
 #include "../logging.hpp"
+#include <base-rs.hpp>

native/jni/base/logging.cpp

@@ -2,41 +2,52 @@
 #include <cstdlib>
 
 #include <flags.h>
+#include <base.hpp>
 
-#include "logging.hpp"
+// Just need to include it somewhere
+#include <base-rs.cpp>
 
 using namespace std;
 
-int nop_log(const char *, va_list) { return 0; }
-
-void nop_ex(int) {}
+void nop_log(const char *, va_list) {}
 
 log_callback log_cb = {
     .d = nop_log,
     .i = nop_log,
     .w = nop_log,
     .e = nop_log,
-    .ex = nop_ex
 };
+static bool EXIT_ON_ERROR = false;
 
-void no_logging() {
-    log_cb.d = nop_log;
-    log_cb.i = nop_log;
-    log_cb.w = nop_log;
-    log_cb.e = nop_log;
-    log_cb.ex = nop_ex;
+static void fmt_and_log_with_rs(LogLevel level, const char *fmt, va_list ap) {
+    char buf[4096];
+    int len = vsnprintf(buf, sizeof(buf), fmt, ap);
+    if (len > 0 && buf[len - 1] == '\n') {
+        // It's unfortunate that all logging on the C++ side always manually include
+        // a newline at the end due to how it was originally implemented.
+        // The logging infrastructure on the rust side does NOT expect a newline
+        // at the end, so we will have to strip it out before sending it over.
+        buf[len - 1] = '\0';
+    }
+    log_with_rs(level, buf);
 }
 
-static int vprintfe(const char *fmt, va_list ap) {
-    return vfprintf(stderr, fmt, ap);
+#define rlog(prio) [](auto fmt, auto ap) { fmt_and_log_with_rs(LogLevel::prio, fmt, ap); }
+static void forward_logging_to_rs() {
+    log_cb.d = rlog(Debug);
+    log_cb.i = rlog(Info);
+    log_cb.w = rlog(Warn);
+    log_cb.e = rlog(Error);
 }
 
 void cmdline_logging() {
-    log_cb.d = vprintfe;
-    log_cb.i = vprintf;
-    log_cb.w = vprintfe;
-    log_cb.e = vprintfe;
-    log_cb.ex = exit;
+    rs::logging::cmdline_logging();
+    forward_logging_to_rs();
+}
+
+void exit_on_error(bool b) {
+    rs::logging::exit_on_error(b);
+    EXIT_ON_ERROR = b;
 }
 
 #define LOG_BODY(prio) { \
@@ -54,9 +65,9 @@ void LOGD(const char *fmt, ...) {}
 #endif
 void LOGI(const char *fmt, ...) { LOG_BODY(i) }
 void LOGW(const char *fmt, ...) { LOG_BODY(w) }
-void LOGE(const char *fmt, ...) { LOG_BODY(e); log_cb.ex(EXIT_FAILURE); }
+void LOGE(const char *fmt, ...) { LOG_BODY(e); if (EXIT_ON_ERROR) exit(EXIT_FAILURE); }
 
 // Export raw symbol to fortify compat
-extern "C" int __vloge(const char* fmt, va_list ap) {
-    return log_cb.e(fmt, ap);
+extern "C" void __vloge(const char* fmt, va_list ap) {
+    log_cb.e(fmt, ap);
 }

native/jni/base/logging.hpp

@@ -4,11 +4,10 @@
 #include <cstdarg>
 
 struct log_callback {
-    int (*d)(const char* fmt, va_list ap);
-    int (*i)(const char* fmt, va_list ap);
-    int (*w)(const char* fmt, va_list ap);
-    int (*e)(const char* fmt, va_list ap);
-    void (*ex)(int code);
+    void (*d)(const char* fmt, va_list ap);
+    void (*i)(const char* fmt, va_list ap);
+    void (*w)(const char* fmt, va_list ap);
+    void (*e)(const char* fmt, va_list ap);
 };
 
 extern log_callback log_cb;
@@ -19,8 +18,7 @@ void LOGW(const char *fmt, ...) __printflike(1, 2);
 void LOGE(const char *fmt, ...) __printflike(1, 2);
 #define PLOGE(fmt, args...) LOGE(fmt " failed with %d: %s\n", ##args, errno, std::strerror(errno))
 
-int nop_log(const char *, va_list);
-void nop_ex(int);
+void nop_log(const char *, va_list);
 
-void no_logging();
 void cmdline_logging();
+void exit_on_error(bool b);

native/jni/core/daemon.cpp

@@ -11,6 +11,8 @@
 #include <resetprop.hpp>
 #include <flags.h>
 
+#include <core-rs.cpp>
+
 #include "core.hpp"
 
 using namespace std;

native/jni/core/logging.cpp

@@ -166,22 +166,22 @@ extern "C" int magisk_log_print(int prio, const char *tag, const char *fmt, ...)
     return ret;
 }
 
-#define mlog(prio) [](auto fmt, auto ap){ return magisk_log(ANDROID_LOG_##prio, fmt, ap); }
+#define mlog(prio) [](auto fmt, auto ap){ magisk_log(ANDROID_LOG_##prio, fmt, ap); }
 void magisk_logging() {
     log_cb.d = mlog(DEBUG);
     log_cb.i = mlog(INFO);
     log_cb.w = mlog(WARN);
     log_cb.e = mlog(ERROR);
-    log_cb.ex = nop_ex;
+    exit_on_error(false);
 }
 
-#define alog(prio) [](auto fmt, auto ap){ return __android_log_vprint(ANDROID_LOG_##prio, "Magisk", fmt, ap); }
+#define alog(prio) [](auto fmt, auto ap){ __android_log_vprint(ANDROID_LOG_##prio, "Magisk", fmt, ap); }
 void android_logging() {
     log_cb.d = alog(DEBUG);
     log_cb.i = alog(INFO);
     log_cb.w = alog(WARN);
     log_cb.e = alog(ERROR);
-    log_cb.ex = nop_ex;
+    exit_on_error(false);
 }
 
 void start_log_daemon() {

native/jni/core/magisk.cpp

@@ -127,6 +127,7 @@ int magisk_main(int argc, char *argv[]) {
 #if 0
     /* Entry point for testing stuffs */
     else if (argv[1] == "--test"sv) {
+        rust_test_entry();
         return 0;
     }
 #endif

native/jni/include/daemon.hpp

@@ -8,6 +8,7 @@
 #include <functional>
 
 #include <socket.hpp>
+#include <core-rs.hpp>
 
 #define AID_ROOT   0
 #define AID_SHELL  2000

native/jni/init/getinfo.cpp

@@ -119,9 +119,9 @@ static bool check_key_combo() {
 
 static FILE *kmsg;
 static char kmsg_buf[4096];
-static int vprintk(const char *fmt, va_list ap) {
+static void vprintk(const char *fmt, va_list ap) {
     vsnprintf(kmsg_buf + 12, sizeof(kmsg_buf) - 12, fmt, ap);
-    return fprintf(kmsg, "%s", kmsg_buf);
+    fprintf(kmsg, "%s", kmsg_buf);
 }
 void setup_klog() {
     // Shut down first 3 fds
@@ -150,7 +150,7 @@ void setup_klog() {
     kmsg = fdopen(fd, "w");
     setbuf(kmsg, nullptr);
     log_cb.d = log_cb.i = log_cb.w = log_cb.e = vprintk;
-    log_cb.ex = nop_ex;
+    exit_on_error(false);
     strcpy(kmsg_buf, "magiskinit: ");
 
     // Disable kmsg rate limiting

native/jni/resetprop/resetprop.cpp

@@ -13,8 +13,6 @@
 
 using namespace std;
 
-static bool verbose = false;
-
 #ifdef APPLET_STUB_MAIN
 #define system_property_set           __system_property_set
 #define system_property_find          __system_property_find
@@ -297,10 +295,9 @@ void load_prop_file(const char *filename, bool prop_svc) {
 }
 
 int resetprop_main(int argc, char *argv[]) {
-    log_cb.d = [](auto fmt, auto ap) -> int { return verbose ? vfprintf(stderr, fmt, ap) : 0; };
-
     bool prop_svc = true;
     bool persist = false;
+    bool verbose = false;
     char *argv0 = argv[0];
 
     --argc;
@@ -340,6 +337,9 @@ int resetprop_main(int argc, char *argv[]) {
         ++argv;
     }
 
+    if (!verbose)
+        log_cb.d = nop_log;
+
     switch (argc) {
     case 0:
         print_props(persist);

native/jni/su/su_daemon.cpp

@@ -311,7 +311,7 @@ void su_daemon_handler(int client, const sock_cred *cred) {
     LOGD("su: fork handler\n");
 
     // Abort upon any error occurred
-    log_cb.ex = exit;
+    exit_on_error(true);
 
     // ack
     write_int(client, 0);

native/jni/zygisk/entry.cpp

@@ -17,15 +17,15 @@ using namespace std;
 
 void *self_handle = nullptr;
 
-static int zygisk_log(int prio, const char *fmt, va_list ap);
+static void zygisk_log(int prio, const char *fmt, va_list ap);
 
-#define zlog(prio) [](auto fmt, auto ap){ return zygisk_log(ANDROID_LOG_##prio, fmt, ap); }
+#define zlog(prio) [](auto fmt, auto ap){ zygisk_log(ANDROID_LOG_##prio, fmt, ap); }
 static void zygisk_logging() {
     log_cb.d = zlog(DEBUG);
     log_cb.i = zlog(INFO);
     log_cb.w = zlog(WARN);
     log_cb.e = zlog(ERROR);
-    log_cb.ex = nop_ex;
+    exit_on_error(false);
 }
 
 // Make sure /proc/self/environ is sanitized
@@ -114,7 +114,7 @@ static void zygisk_init() {
 
 // The following code runs in zygote/app process
 
-static int zygisk_log(int prio, const char *fmt, va_list ap) {
+static void zygisk_log(int prio, const char *fmt, va_list ap) {
     // If we don't have log pipe set, ask magiskd for it
     // This could happen multiple times in zygote because it was closed to prevent crashing
     if (logd_fd < 0) {
@@ -139,13 +139,12 @@ static int zygisk_log(int prio, const char *fmt, va_list ap) {
         sigaddset(&mask, SIGPIPE);
         pthread_sigmask(SIG_BLOCK, &mask, &orig_mask);
     }
-    int ret = magisk_log(prio, fmt, ap);
+    magisk_log(prio, fmt, ap);
     if (sig) {
         timespec ts{};
         sigtimedwait(&mask, nullptr, &ts);
         pthread_sigmask(SIG_SETMASK, &orig_mask, nullptr);
     }
-    return ret;
 }
 
 static inline bool should_load_modules(uint32_t flags) {

native/rust/Cargo.lock

@@ -5,6 +5,9 @@ version = 3
 [[package]]
 name = "base"
 version = "0.1.0"
+dependencies = [
+ "cxx",
+]
 
 [[package]]
 name = "cc"

native/rust/base/Cargo.toml

@@ -4,3 +4,4 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
+cxx = "1.0.69"

native/rust/base/src/lib.rs

@@ -0,0 +1,25 @@
+pub use logging::*;
+
+mod logging;
+
+#[cxx::bridge]
+pub mod ffi {
+    pub enum LogLevel {
+        Error,
+        Warn,
+        Info,
+        Debug,
+    }
+
+    extern "Rust" {
+        fn log_with_rs(level: LogLevel, msg: &str);
+    }
+}
+
+#[cxx::bridge(namespace = "rs::logging")]
+pub mod ffi2 {
+    extern "Rust" {
+        fn cmdline_logging();
+        fn exit_on_error(b: bool);
+    }
+}

native/rust/base/src/logging.rs

@@ -0,0 +1,91 @@
+use std::fmt::Arguments;
+use std::process::exit;
+
+use crate::ffi::LogLevel;
+
+// We don't need to care about thread safety, because all
+// logger changes will only happen on the main thread.
+pub static mut LOGGER: Logger = Logger {
+    d: nop_log,
+    i: nop_log,
+    w: nop_log,
+    e: nop_log,
+};
+static mut EXIT_ON_ERROR: bool = false;
+
+#[derive(Copy, Clone)]
+pub struct Logger {
+    pub d: fn(args: Arguments),
+    pub i: fn(args: Arguments),
+    pub w: fn(args: Arguments),
+    pub e: fn(args: Arguments),
+}
+
+pub fn nop_log(_: Arguments) {}
+
+fn println(args: Arguments) { println!("{}", args); }
+
+fn eprintln(args: Arguments) { eprintln!("{}", args); }
+
+pub fn log_with_rs(level: LogLevel, msg: &str) {
+    log_impl(level, format_args!("{}", msg));
+}
+
+pub fn exit_on_error(b: bool) {
+    unsafe { EXIT_ON_ERROR = b; }
+}
+
+pub fn cmdline_logging() {
+    let logger = Logger {
+        d: eprintln,
+        i: println,
+        w: eprintln,
+        e: eprintln,
+    };
+    unsafe {
+        LOGGER = logger;
+        EXIT_ON_ERROR = true;
+    }
+}
+
+pub fn log_impl(level: LogLevel, args: Arguments) {
+    let logger = unsafe { LOGGER };
+    let aoe = unsafe { EXIT_ON_ERROR };
+    match level {
+        LogLevel::Error => {
+            (logger.e)(args);
+            if aoe { exit(1); }
+        }
+        LogLevel::Warn => (logger.w)(args),
+        LogLevel::Info => (logger.i)(args),
+        LogLevel::Debug => (logger.d)(args),
+        _ => ()
+    }
+}
+
+#[macro_export]
+macro_rules! error {
+    ($($arg:tt)+) => ($crate::log_impl($crate::ffi::LogLevel::Error, format_args!($($arg)+)))
+}
+
+#[macro_export]
+macro_rules! warn {
+    ($($arg:tt)+) => ($crate::log_impl($crate::ffi::LogLevel::Warn, format_args!($($arg)+)))
+}
+
+#[macro_export]
+macro_rules! info {
+    ($($arg:tt)+) => ($crate::log_impl($crate::ffi::LogLevel::Info, format_args!($($arg)+)))
+}
+
+#[cfg(debug_assertions)]
+#[macro_export]
+macro_rules! debug {
+    ($($arg:tt)+) => ($crate::log_impl($crate::ffi::LogLevel::Debug, format_args!($($arg)+)))
+}
+
+#[cfg(not(debug_assertions))]
+#[macro_export]
+macro_rules! debug {
+    ($($arg:tt)+) => ()
+}

native/rust/boot/src/lib.rs

@@ -0,0 +1 @@
+pub use base;

native/rust/core/src/lib.rs

@@ -0,0 +1,10 @@
+pub use base;
+
+#[cxx::bridge]
+pub mod ffi {
+    extern "Rust" {
+        fn rust_test_entry();
+    }
+}
+
+fn rust_test_entry() {}

native/rust/init/src/lib.rs

@@ -0,0 +1 @@
+pub use base;

native/rust/sepolicy/src/lib.rs

@@ -0,0 +1 @@
+pub use base;