Various improvements

Allow &[bool], since Rust has committed to a 1-byte representation of `bool`.
Re-export several types from `widestring` so that code generated by the
`trace_logging_provider` macro no longer has a direct reference to the
`widestring` crate.

Update docs.

README.md

@@ -88,9 +88,13 @@ call into ETW to report the event, but there is no guarantee that the event is s
 forwarded; events can be dropped if event buffer resources are scarce.
 
 ```rust
-my_app_events.client_connected(&"192.168.0.42:6667".parse(), false, 100, "OK");
+my_app_events.client_connected(None, &"192.168.0.42:6667".parse(), false, 100, "OK");
 ```
 
+Note that all generated event methods have an added first parameters,
+`options: Option<&EventOptions>`. This parameter allows you to override per-event parameters,
+such as the event level and event correlation IDs. In most cases, you should pass `None`.
+
 # Supported field types
 Only a limited set of field types are supported.
 
@@ -98,8 +102,7 @@ Only a limited set of field types are supported.
 * Floating point primitives: `f32`, `f64`
 * Architecture-dependent sizes: `usize`, `isize`.
 * Boolean: `bool`
-* Slices of all of the supported primitives, except for bool: `&[u8]`, `&[u16]`, etc.
-  `&[bool]` is not supported because `bool` does not have a guaranteed stable representation.
+* Slices of all of the supported primitives: `&[u8]`, `&[u16]`, etc.
 * Windows `[FILETIME](https://docs.microsoft.com/en-us/windows/win32/api/minwinbase/ns-minwinbase-filetime)`.
   The type must be declared _exactly_ as `FILETIME`; type aliases or fully-qualified paths
   (such as `winapi::shared::minwindef::FILETIME`) _will not work_. The parameter type in the
@@ -134,6 +137,10 @@ These tools can also be used to capture ETW events:
 
 There are other tools, such as the Windows Performance Recorder, which can capture ETW events.
 
+# Ideas for improvement
+
+* Better handling of per-event overrides, rather than using `Option<&EventOptions>`.
+
 # References
 
 * [Event Tracing for Windows (ETW) Simplified](https://support.microsoft.com/en-us/help/2593157/event-tracing-for-windows-etw-simplified)

examples/hello_world/src/main.rs

@@ -153,7 +153,7 @@ trait TestManyEvents {
     fn arg_usize(a: usize);
     fn arg_isize(a: isize);
 
-    // fn arg_slice_bool(a: &[bool]);
+    fn arg_slice_bool(a: &[bool]);
     fn arg_slice_u8(a: &[u8]);
     fn arg_slice_u16(a: &[u16]);
     fn arg_slice_u32(a: &[u32]);

win_etw_macros/src/lib.rs

@@ -778,9 +778,9 @@ fn parse_event_field(
                 statements.extend(quote! {
                     let #field_desc: EventDataDescriptor;
                     let #field_len: u16;
-                    let #field_u16cstring: ::widestring::U16CString;
-                    let #field_u16cstr: &::widestring::U16CStr;
-                    match ::widestring::U16CString::from_os_str(#field_name) {
+                    let #field_u16cstring: ::win_etw_provider::types::U16CString;
+                    let #field_u16cstr: &::win_etw_provider::types::U16CStr;
+                    match ::win_etw_provider::types::U16CString::from_os_str(#field_name) {
                         Ok(s) => {
                             #field_u16cstring = s;
                             #field_u16cstr = #field_u16cstring.as_ref();

win_etw_macros/src/tests.rs

@@ -128,6 +128,7 @@ test_case! {
             fn arg_usize(a: usize);
             fn arg_isize(a: isize);
 
+            fn arg_slice_bool(a: &[bool]);
             fn arg_slice_u8(a: &[u8]);
             fn arg_slice_u16(a: &[u16]);
             fn arg_slice_u32(a: &[u32]);

win_etw_provider/src/data_descriptor.rs

@@ -130,6 +130,7 @@ macro_rules! well_known_types {
 }
 
 well_known_types! {
+    bool;
     u8; u16; u32; u64;
     i8; i16; i32; i64;
     f32; f64;

win_etw_provider/src/lib.rs

@@ -8,15 +8,24 @@
 
 mod guid;
 mod provider;
-mod types;
 
+pub mod types;
+
+#[doc(inline)]
 pub use guid::GUID;
+
+#[doc(inline)]
 pub use provider::*;
+
+#[doc(hidden)]
 pub use types::*;
 
+#[doc(hidden)]
 pub use win_etw_metadata as metadata;
+
 mod data_descriptor;
 
+#[doc(inline)]
 pub use data_descriptor::EventDataDescriptor;
 
 /// Errors returned by `win_etw_provider` functions.

win_etw_provider/src/types.rs

@@ -1,3 +1,10 @@
+//! Contains items that are part of the implementation of `win_etw`, but not intended to be used
+//! directly by application code. Only code generated by the `trace_logging_provider` macro
+//! should use these types.
+#![doc(hidden)]
+
+pub use widestring::{U16CStr, U16CString};
+
 use crate::EventDataDescriptor;
 use zerocopy::{AsBytes, FromBytes};