refactoring: move c4log_setRustCallback to our code

Author: Dushistov

couchbase-lite-core-sys/Cargo.toml

@@ -9,4 +9,4 @@ edition = "2018"
 [build-dependencies]
 cmake = "0.1.42"
 bindgen = "0.53.2"
-cc = "1.0.48"
+cc = "1.0.53"

couchbase-lite-core-sys/build.rs

@@ -80,6 +80,7 @@ fn main() {
             .join("fleece")
             .join("API"),
         Path::new("couchbase-lite-core").into(),
+        Path::new(".").into(),
     ];
     let target = getenv_unwrap("TARGET");
     let mut framework_dirs = vec![];
@@ -100,10 +101,23 @@ fn main() {
             "c4Document+Fleece.h",
             "fleece/Fleece.h",
             "Replicator/CivetWebSocket.hh",
+            "couch_lite_log_retrans.hpp",
         ],
         &out_dir.join("c4_header.rs"),
     )
     .expect("bindgen failed");
+
+    let mut cc_builder = cc::Build::new();
+
+    for inc in &includes {
+        cc_builder.include(inc);
+    }
+
+    cc_builder
+        .cpp(true)
+        .flag_if_supported("-std=c++11")
+        .file("couch_lite_log_retrans.cpp")
+        .compile("couch_lite_log_retrans");
 }
 
 /// Convert something like

couchbase-lite-core-sys/couch_lite_log_retrans.cpp

@@ -0,0 +1,20 @@
+#include <atomic>
+
+#include "couch_lite_log_retrans.hpp"
+
+
+static std::atomic<C4LogCallbackR> g_rust_log_callback{nullptr};
+
+static void rust_log_callback(C4LogDomain d, C4LogLevel l,
+                              const char *fmt C4NONNULL, va_list) {
+  C4LogCallbackR rust_log_callback = g_rust_log_callback.load(std::memory_order_relaxed);
+  if (rust_log_callback != nullptr) {
+    rust_log_callback(d, l, fmt);
+  }
+}
+
+void c4log_setRustCallback(C4LogLevel level, C4LogCallbackR callback) noexcept {
+  g_rust_log_callback.store(callback, std::memory_order_relaxed);
+  c4log_writeToCallback(level, rust_log_callback, true);
+}
+

couchbase-lite-core-sys/couch_lite_log_retrans.hpp

@@ -0,0 +1,15 @@
+#pragma once
+
+#include "c4Base.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef void (*C4LogCallbackR)(C4LogDomain, C4LogLevel, const char *msg C4NONNULL);
+
+void c4log_setRustCallback(C4LogLevel level, C4LogCallbackR callback) C4API;
+
+#ifdef __cplusplus
+}
+#endif