feat(os): add Linux syslog OS wrapper for score::os::Syslog

score/os/BUILD

@@ -297,6 +297,32 @@ cc_library(
     ],
 )
 
+cc_library(
+    name = "syslog_impl",
+    srcs = [
+        "syslog.cpp",
+        "syslog_impl.cpp",
+    ],
+    hdrs = [
+        "syslog.h",
+        "syslog_impl.h",
+    ],
+    features = COMPILER_WARNING_FEATURES,
+    tags = ["FFI"],
+    target_compatible_with = ["@platforms//os:linux"],
+    visibility = ["//visibility:public"],
+    deps = [
+        ":errno",
+        ":object_seam",
+    ],
+)
+
+alias(
+    name = "syslog",
+    actual = "syslog_impl",
+    visibility = ["//visibility:public"],
+)
+
 cc_library(
     name = "arpa_inet",
     srcs = ["arpa_inet.cpp"],

score/os/mocklib/BUILD

@@ -26,6 +26,19 @@ cc_library(
     ],
 )
 
+cc_library(
+    name = "syslog_mock",
+    testonly = True,
+    srcs = ["mock_syslog.cpp"],
+    hdrs = ["mock_syslog.h"],
+    target_compatible_with = ["@platforms//os:linux"],
+    visibility = ["//visibility:public"],
+    deps = [
+        "@googletest//:gtest",
+        "@score_baselibs//score/os:syslog",
+    ],
+)
+
 cc_library(
     name = "pthread_mock",
     testonly = True,

score/os/mocklib/mock_syslog.cpp

@@ -0,0 +1,53 @@
+/********************************************************************************
+ * Copyright (c) 2026 Contributors to the Eclipse Foundation
+ *
+ * See the NOTICE file(s) distributed with this work for additional
+ * information regarding copyright ownership.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Apache License Version 2.0 which is available at
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ ********************************************************************************/
+#include "score/os/mocklib/mock_syslog.h"
+
+#include <cstdarg>
+#include <cstdio>
+#include <string>
+
+namespace score
+{
+namespace os
+{
+
+// NOLINTNEXTLINE(cert-dcl50-cpp, modernize-avoid-variadic-functions)
+void MockSyslog::syslog(std::int32_t priority, const char* format, ...) const noexcept
+{
+    // Create a va_list to hold the variable arguments
+    va_list args;
+    va_start(args, format);
+
+    // Determine required buffer size
+    const auto message_length = std::vsnprintf(nullptr, 0, format, args);
+
+    // Reset the va_list to be able to use it again
+    va_end(args);
+    va_start(args, format);
+
+    // Create buffer
+    std::string message{};
+    message.resize(static_cast<std::size_t>(message_length));
+
+    // Write formatted string to buffer
+    const auto length_including_terminator = static_cast<std::size_t>(message_length) + 1U;
+    std::vsnprintf(&message[0], length_including_terminator, format, args);
+
+    // Clean up the va_list
+    va_end(args);
+
+    MockedSyslog(priority, message);
+}
+
+}  // namespace os
+}  // namespace score

score/os/mocklib/mock_syslog.h

@@ -0,0 +1,49 @@
+/********************************************************************************
+ * Copyright (c) 2026 Contributors to the Eclipse Foundation
+ *
+ * See the NOTICE file(s) distributed with this work for additional
+ * information regarding copyright ownership.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Apache License Version 2.0 which is available at
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ ********************************************************************************/
+#ifndef SCORE_LIB_OS_MOCKLIB_MOCK_SYSLOG_H
+#define SCORE_LIB_OS_MOCKLIB_MOCK_SYSLOG_H
+
+#include "score/os/syslog.h"
+
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+
+#include <string>
+
+namespace score
+{
+namespace os
+{
+
+class MockSyslog : public Syslog
+{
+  public:
+    MOCK_METHOD(void,
+                openlog,
+                (const char* ident, std::int32_t option, std::int32_t facility),
+                (const, noexcept, override));
+
+    MOCK_METHOD(void, closelog, (), (const, noexcept, override));
+
+    // Googletest does not support variadic arguments. Therefore we pass through the formatted string so that we can
+    // use it with MOCK_METHOD.
+    MOCK_METHOD(void, MockedSyslog, (std::int32_t priority, const std::string& message), (const, noexcept));
+
+    void syslog(std::int32_t priority, const char* format, ...) const noexcept override
+        __attribute__((format(printf, 3, 4)));
+};
+
+}  // namespace os
+}  // namespace score
+
+#endif  // SCORE_LIB_OS_MOCKLIB_MOCK_SYSLOG_H

score/os/syslog.cpp

@@ -0,0 +1,29 @@
+/********************************************************************************
+ * Copyright (c) 2026 Contributors to the Eclipse Foundation
+ *
+ * See the NOTICE file(s) distributed with this work for additional
+ * information regarding copyright ownership.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Apache License Version 2.0 which is available at
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ ********************************************************************************/
+#include "score/os/syslog.h"
+
+#include "score/os/syslog_impl.h"
+
+namespace score
+{
+namespace os
+{
+
+/* score::cpp::pmr::make_unique takes non-const memory_resource */
+score::cpp::pmr::unique_ptr<Syslog> Syslog::Default(score::cpp::pmr::memory_resource* memory_resource) noexcept
+{
+    return score::cpp::pmr::make_unique<SyslogImpl>(memory_resource);
+}
+
+}  // namespace os
+}  // namespace score

score/os/syslog.h

@@ -0,0 +1,57 @@
+/********************************************************************************
+ * Copyright (c) 2026 Contributors to the Eclipse Foundation
+ *
+ * See the NOTICE file(s) distributed with this work for additional
+ * information regarding copyright ownership.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Apache License Version 2.0 which is available at
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ ********************************************************************************/
+#ifndef SCORE_LIB_OS_SYSLOG_H
+#define SCORE_LIB_OS_SYSLOG_H
+
+#include "score/os/errno.h"
+
+#include "score/memory.hpp"
+
+#include <syslog.h>
+
+namespace score
+{
+namespace os
+{
+
+/// @brief Object-seam wrapper around the POSIX/glibc syslog(3) family, allowing
+/// openlog/syslog/closelog to be mocked in host unit tests.
+class Syslog
+{
+  public:
+    static score::cpp::pmr::unique_ptr<Syslog> Default(score::cpp::pmr::memory_resource* memory_resource) noexcept;
+
+    virtual void openlog(const char* const ident,
+                         const std::int32_t option,
+                         const std::int32_t facility) const noexcept = 0;
+
+    virtual void syslog(const std::int32_t priority, const char* const format, ...) const noexcept
+        __attribute__((format(printf, 3, 4))) = 0;
+
+    virtual void closelog() const noexcept = 0;
+
+    /// @brief Construct a new Syslog object
+    ///
+    Syslog() = default;
+
+    virtual ~Syslog() = default;
+    Syslog(const Syslog&) = delete;
+    Syslog& operator=(const Syslog&) = delete;
+    Syslog(Syslog&& other) = delete;
+    Syslog& operator=(Syslog&& other) = delete;
+};
+
+}  // namespace os
+}  // namespace score
+
+#endif  // SCORE_LIB_OS_SYSLOG_H

score/os/syslog_impl.cpp

@@ -0,0 +1,50 @@
+/********************************************************************************
+ * Copyright (c) 2026 Contributors to the Eclipse Foundation
+ *
+ * See the NOTICE file(s) distributed with this work for additional
+ * information regarding copyright ownership.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Apache License Version 2.0 which is available at
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ ********************************************************************************/
+#include "score/os/syslog_impl.h"
+
+#include <cstdarg>
+
+namespace score
+{
+namespace os
+{
+
+void SyslogImpl::openlog(const char* const ident, const std::int32_t option, const std::int32_t facility) const noexcept
+{
+    ::openlog(ident, option, facility);
+}
+
+// NOLINTNEXTLINE(cert-dcl50-cpp, modernize-avoid-variadic-functions)
+void SyslogImpl::syslog(const std::int32_t priority, const char* const format, ...) const noexcept
+{
+    // Suppressed here because POSIX method accepts va_list
+    // NOLINTNEXTLINE(cppcoreguidelines-pro-type-vararg) see comment above
+    va_list args;
+    // Suppressed here because POSIX method accepts va_list
+    // NOLINTNEXTLINE(hicpp-no-array-decay, cppcoreguidelines-pro-type-vararg) see comment above
+    va_start(args, format);  // NOLINT(cppcoreguidelines-pro-bounds-array-to-pointer-decay) see comment above
+    // Suppressed here because POSIX method accepts va_list
+    // NOLINTNEXTLINE(*array-decay, *pro-type-vararg,*array-to-pointer-decay) see comment above
+    ::vsyslog(priority, format, args);
+    // Suppressed here because POSIX method accepts va_list
+    // NOLINTNEXTLINE(hicpp-no-array-decay, cppcoreguidelines-pro-type-vararg) see comment above
+    va_end(args);  // NOLINT(cppcoreguidelines-pro-bounds-array-to-pointer-decay) see comment above
+}
+
+void SyslogImpl::closelog() const noexcept
+{
+    ::closelog();
+}
+
+}  // namespace os
+}  // namespace score

score/os/syslog_impl.h

@@ -0,0 +1,39 @@
+/********************************************************************************
+ * Copyright (c) 2026 Contributors to the Eclipse Foundation
+ *
+ * See the NOTICE file(s) distributed with this work for additional
+ * information regarding copyright ownership.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Apache License Version 2.0 which is available at
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ ********************************************************************************/
+#ifndef SCORE_LIB_OS_SYSLOG_IMPL_H
+#define SCORE_LIB_OS_SYSLOG_IMPL_H
+
+#include "score/os/syslog.h"
+
+namespace score
+{
+namespace os
+{
+
+class SyslogImpl : public Syslog
+{
+  public:
+    void openlog(const char* const ident,
+                 const std::int32_t option,
+                 const std::int32_t facility) const noexcept override;
+
+    void syslog(const std::int32_t priority, const char* const format, ...) const noexcept override
+        __attribute__((format(printf, 3, 4)));
+
+    void closelog() const noexcept override;
+};
+
+}  // namespace os
+}  // namespace score
+
+#endif  // SCORE_LIB_OS_SYSLOG_IMPL_H

score/os/test/linux/BUILD

@@ -18,6 +18,7 @@ test_suite(
     name = "unit_tests_linux",
     tests = [
         ":pthread_test",
+        ":syslog_test",
         ":unistd_test",
     ],
     visibility = ["@score_baselibs//score/os/test:__subpackages__"],
@@ -53,3 +54,19 @@ cc_test(
         "@score_baselibs//score/os:pthread",
     ],
 )
+
+cc_test(
+    name = "syslog_test",
+    srcs = [
+        "syslog_test.cpp",
+    ],
+    features = COMPILER_WARNING_FEATURES,
+    tags = [
+        "unit",
+    ],
+    target_compatible_with = ["@platforms//os:linux"],
+    deps = [
+        "@googletest//:gtest_main",
+        "@score_baselibs//score/os:syslog",
+    ],
+)