Add tracing subscriber to enable logging

.github/workflows/build.yml

@@ -44,6 +44,7 @@ jobs:
 :TracingTests.*\
 :ByNameTests.*\
 :CompressionTests.*\
+:LoggingTests.*\
 :-PreparedTests.Integration_Cassandra_PreparedIDUnchangedDuringReprepare\
 :*5.Integration_Cassandra_*\
 :*19.Integration_Cassandra_*"

.github/workflows/cassandra.yml

@@ -49,6 +49,7 @@ jobs:
 :TracingTests.*\
 :ByNameTests.*\
 :CompressionTests.*\
+:LoggingTests.*\
 :-PreparedTests.Integration_Cassandra_PreparedIDUnchangedDuringReprepare\
 :*5.Integration_Cassandra_*\
 :*19.Integration_Cassandra_*\

scylla-rust-wrapper/Cargo.toml

@@ -22,6 +22,8 @@ num-derive = "0.3"
 libc = "0.2.108"
 openssl-sys = "0.9.75"
 openssl = "0.10.32"
+tracing-subscriber = { version = "0.3.15", features = ["env-filter"] }
+tracing = "0.1.25"
 
 [build-dependencies]
 bindgen = "0.59.1"

scylla-rust-wrapper/build.rs

@@ -90,6 +90,16 @@ fn main() {
         &["CassInet_", "CassInet"],
         &out_path,
     );
+    prepare_cppdriver_data(
+        "cppdriver_log.rs",
+        &[
+            "CassLogLevel_",
+            "CassLogLevel",
+            "CassLogMessage_",
+            "CassLogMessage",
+        ],
+        &out_path,
+    );
     prepare_cppdriver_data(
         "cppdriver_data_query_error.rs",
         &[

scylla-rust-wrapper/src/argconv.rs

@@ -1,4 +1,5 @@
 use crate::types::size_t;
+use std::cmp::min;
 use std::ffi::CStr;
 use std::os::raw::c_char;
 use std::sync::Arc;
@@ -38,6 +39,29 @@ pub unsafe fn ptr_to_cstr_n(ptr: *const c_char, size: size_t) -> Option<&'static
     std::str::from_utf8(std::slice::from_raw_parts(ptr as *const u8, size as usize)).ok()
 }
 
+pub unsafe fn arr_to_cstr<const N: usize>(arr: &[c_char]) -> Option<&'static str> {
+    let null_char = '\0' as c_char;
+    let end_index = arr[..N].iter().position(|c| c == &null_char).unwrap_or(N);
+    ptr_to_cstr_n(arr.as_ptr(), end_index as size_t)
+}
+
+pub fn str_to_arr<const N: usize>(s: &str) -> [c_char; N] {
+    let mut result = ['\0' as c_char; N];
+
+    // Max length must be null-terminated
+    let mut max_len = min(N - 1, s.as_bytes().len());
+
+    while !s.is_char_boundary(max_len) {
+        max_len -= 1;
+    }
+
+    for (i, c) in s.as_bytes().iter().enumerate().take(max_len) {
+        result[i] = *c as c_char;
+    }
+
+    result
+}
+
 pub unsafe fn write_str_to_c(s: &str, c_str: *mut *const c_char, c_strlen: *mut size_t) {
     *c_str = s.as_ptr() as *const c_char;
     *c_strlen = s.len() as u64;

scylla-rust-wrapper/src/lib.rs

@@ -1,6 +1,12 @@
 #![allow(clippy::missing_safety_doc)]
+
+use crate::logging::set_tracing_subscriber_with_level;
+use crate::logging::stderr_log_callback;
+use crate::logging::Logger;
 use lazy_static::lazy_static;
+use std::sync::RwLock;
 use tokio::runtime::Runtime;
+use tracing::dispatcher::DefaultGuard;
 
 #[macro_use]
 mod binding;
@@ -13,6 +19,7 @@ pub mod collection;
 mod external;
 pub mod future;
 pub mod inet;
+mod logging;
 pub mod prepared;
 pub mod query_error;
 pub mod query_result;
@@ -28,6 +35,13 @@ pub mod uuid;
 
 lazy_static! {
     pub static ref RUNTIME: Runtime = Runtime::new().unwrap();
+    pub static ref LOGGER: RwLock<Logger> = RwLock::new(Logger {
+        cb: Some(stderr_log_callback),
+        data: std::ptr::null_mut(),
+    });
+    pub static ref LOG: RwLock<Option<DefaultGuard>> = RwLock::new(Some(
+        set_tracing_subscriber_with_level(tracing::Level::WARN)
+    ));
 }
 
 // To send a Rust object to C: