feat: Add debug log mask support

Cargo.toml

@@ -6,7 +6,7 @@ members = [
 
 [package]
 name = "ngx"
-version = "0.3.0-beta"
+version = "0.4.0-beta"
 edition = "2021"
 autoexamples = false
 categories = ["api-bindings", "network-programming"]

src/log.rs

@@ -1,3 +1,27 @@
+// Utility function to provide typed checking of the mask's field state.
+#[inline(always)]
+fn check_mask(mask: DebugMasks, log_level: usize) -> bool {
+    let mask_bits: u32 = mask.into();
+    if log_level & mask_bits as usize == 0 {
+        return false;
+    }
+    true
+}
+
+// Internal macro, provided to reduce code duplication.
+//
+// Expects an ngx_log_t and message format template.
+macro_rules! _ngx_log_debug_internal {
+    ( $log:expr, $($arg:tt)* ) => {
+        let level = $crate::ffi::NGX_LOG_DEBUG as $crate::ffi::ngx_uint_t;
+        let fmt = ::std::ffi::CString::new("%s").unwrap();
+        let c_message = ::std::ffi::CString::new(format!($($arg)*)).unwrap();
+        unsafe {
+            $crate::ffi::ngx_log_error_core(level, $log, 0, fmt.as_ptr(), c_message.as_ptr());
+        }
+    }
+}
+
 /// Write to logger at a specified level.
 ///
 /// See [Logging](https://nginx.org/en/docs/dev/development_guide.html#logging)
@@ -7,12 +31,7 @@ macro_rules! ngx_log_debug {
     ( $log:expr, $($arg:tt)* ) => {
         let log_level = unsafe { (*$log).log_level };
         if log_level != 0 {
-            let level = $crate::ffi::NGX_LOG_DEBUG as $crate::ffi::ngx_uint_t;
-            let fmt = ::std::ffi::CString::new("%s").unwrap();
-            let c_message = ::std::ffi::CString::new(format!($($arg)*)).unwrap();
-            unsafe {
-                $crate::ffi::ngx_log_error_core(level, $log, 0, fmt.as_ptr(), c_message.as_ptr());
-            }
+            $crate::_ngx_log_debug_internal!($log, $($arg)*);
         }
     }
 }
@@ -27,3 +46,136 @@ macro_rules! ngx_log_debug_http {
         $crate::ngx_log_debug!(log, $($arg)*);
     }
 }
+
+/// Debug masks for use with ngx_log_debug_mask, these represent the only accepted values for the
+/// mask.
+#[derive(Debug)]
+pub enum DebugMasks {
+    /// Aligns to the NGX_LOG_DEBUG_CORE mask.
+    Core,
+    /// Aligns to the NGX_LOG_DEBUG_ALLOC mask.
+    Alloc,
+    /// Aligns to the NGX_LOG_DEBUG_MUTEX mask.
+    Mutex,
+    /// Aligns to the NGX_LOG_DEBUG_EVENT mask.
+    Event,
+    /// Aligns to the NGX_LOG_DEBUG_HTTP mask.
+    Http,
+    /// Aligns to the NGX_LOG_DEBUG_MAIL mask.
+    Mail,
+    /// Aligns to the NGX_LOG_DEBUG_STREAM mask.
+    Stream,
+}
+
+impl TryFrom<u32> for DebugMasks {
+    type Error = u32;
+
+    fn try_from(value: u32) -> Result<Self, Self::Error> {
+        match value {
+            crate::ffi::NGX_LOG_DEBUG_CORE => Ok(DebugMasks::Core),
+            crate::ffi::NGX_LOG_DEBUG_ALLOC => Ok(DebugMasks::Alloc),
+            crate::ffi::NGX_LOG_DEBUG_MUTEX => Ok(DebugMasks::Mutex),
+            crate::ffi::NGX_LOG_DEBUG_EVENT => Ok(DebugMasks::Event),
+            crate::ffi::NGX_LOG_DEBUG_HTTP => Ok(DebugMasks::Http),
+            crate::ffi::NGX_LOG_DEBUG_MAIL => Ok(DebugMasks::Mail),
+            crate::ffi::NGX_LOG_DEBUG_STREAM => Ok(DebugMasks::Stream),
+            _ => Err(0),
+        }
+    }
+}
+
+impl From<DebugMasks> for u32 {
+    fn from(value: DebugMasks) -> Self {
+        match value {
+            DebugMasks::Core => crate::ffi::NGX_LOG_DEBUG_CORE,
+            DebugMasks::Alloc => crate::ffi::NGX_LOG_DEBUG_ALLOC,
+            DebugMasks::Mutex => crate::ffi::NGX_LOG_DEBUG_MUTEX,
+            DebugMasks::Event => crate::ffi::NGX_LOG_DEBUG_EVENT,
+            DebugMasks::Http => crate::ffi::NGX_LOG_DEBUG_HTTP,
+            DebugMasks::Mail => crate::ffi::NGX_LOG_DEBUG_MAIL,
+            DebugMasks::Stream => crate::ffi::NGX_LOG_DEBUG_STREAM,
+        }
+    }
+}
+
+/// Log with appropriate debug mask.
+///
+/// When the request logger is available `ngx_log_debug_http` can be used for `NGX_LOG_DEBUG_HTTP` masks.
+/// This macro is useful when other masks are necessary or when the request logger is not
+/// conveniently accessible.
+///
+/// See https://nginx.org/en/docs/dev/development_guide.html#logging for details and available
+/// masks.
+#[macro_export]
+macro_rules! ngx_log_debug_mask {
+    ( DebugMasks::Core, $log:expr, $($arg:tt)* ) => ({
+        let log_level = unsafe { (*$log).log_level };
+        if check_mask(DebugMasks::Core, log_level) {
+            $crate::_ngx_log_debug_internal!(log, $($arg:tt)*);
+        }
+    });
+    ( DebugMasks::Alloc, $log:expr, $($arg:tt)* ) => ({
+        let log_level = unsafe { (*$log).log_level };
+        if check_mask(DebugMasks::Alloc, log_level) {
+            $crate::_ngx_log_debug_internal!(log, $($arg:tt)*);
+        }
+    });
+    ( DebugMasks::Mutex, $log:expr, $($arg:tt)* ) => ({
+        let log_level = unsafe { (*$log).log_level };
+        if check_mask(DebugMasks::Mutex, log_level) {
+            $crate::_ngx_log_debug_internal!(log, $($arg:tt)*);
+        }
+    });
+    ( DebugMasks::Event, $log:expr, $($arg:tt)* ) => ({
+        let log_level = unsafe { (*$log).log_level };
+        if check_mask(DebugMasks::Event, log_level) {
+            $crate::_ngx_log_debug_internal!(log, $($arg:tt)*);
+        }
+    });
+    ( DebugMasks::Http, $log:expr, $($arg:tt)* ) => ({
+        let log_level = unsafe { (*$log).log_level };
+        if check_mask(DebugMasks::Http, log_level) {
+            $crate::_ngx_log_debug_internal!(log, $($arg:tt)*);
+        }
+    });
+    ( DebugMasks::Mail, $log:expr, $($arg:tt)* ) => ({
+        let log_level = unsafe { (*$log).log_level };
+        if check_mask(DebugMasks::Mail, log_level) {
+            $crate::_ngx_log_debug_internal!(log, $($arg:tt)*);
+        }
+    });
+    ( DebugMasks::Stream, $log:expr, $($arg:tt)* ) => ({
+        let log_level = unsafe { (*$log).log_level };
+        if check_mask(DebugMasks::Stream, log_level) {
+            $crate::_ngx_log_debug_internal!(log, $($arg:tt)*);
+        }
+    });
+}
+
+#[cfg(test)]
+mod tests {
+
+    use super::*;
+
+    #[test]
+    fn test_mask_lower_bound() {
+        assert!(<DebugMasks as Into<u32>>::into(DebugMasks::Core) == crate::ffi::NGX_LOG_DEBUG_FIRST);
+    }
+    #[test]
+    fn test_mask_upper_bound() {
+        assert!(<DebugMasks as Into<u32>>::into(DebugMasks::Stream) == crate::ffi::NGX_LOG_DEBUG_LAST);
+    }
+    #[test]
+    fn test_check_mask() {
+        struct MockLog {
+            log_level: usize,
+        }
+        let mock = MockLog { log_level: 16 };
+
+        let mut r = check_mask(DebugMasks::Core, mock.log_level);
+        assert!(r == true);
+
+        r = check_mask(DebugMasks::Alloc, mock.log_level);
+        assert!(r == false);
+    }
+}