[NativeAOT] Migrate runtime utility logging to printf

src/native/clr/host/host-shared.cc

@@ -12,13 +12,13 @@ auto HostCommon::get_java_class_name_for_TypeManager (jclass klass) noexcept ->
 	JNIEnv *env = OSBridge::ensure_jnienv ();
 	jstring name = reinterpret_cast<jstring> (env->CallObjectMethod (klass, Class_getName));
 	if (name == nullptr) {
-		log_error (LOG_DEFAULT, "Failed to obtain Java class name for object at {:p}", reinterpret_cast<void*>(klass));
+		log_errorf (LOG_DEFAULT, "Failed to obtain Java class name for object at %p", reinterpret_cast<void*>(klass));
 		return nullptr;
 	}
 
 	const char *mutf8 = env->GetStringUTFChars (name, nullptr);
 	if (mutf8 == nullptr) {
-		log_error (LOG_DEFAULT, "Failed to convert Java class name to UTF8 (out of memory?)"sv);
+		log_errorf (LOG_DEFAULT, "Failed to convert Java class name to UTF8 (out of memory?)");
 		env->DeleteLocalRef (name);
 		return nullptr;
 	}

src/native/clr/include/runtime-base/util.hh

@@ -139,7 +139,7 @@ namespace xamarin::android {
 		{
 			struct stat sbuf;
 			if (fstatat (dirfd, file_name, &sbuf, 0) == -1) {
-				log_warn (LOG_ASSEMBLY, "Failed to stat file '{}': {}", file_name, std::strerror (errno));
+				log_warnf (LOG_ASSEMBLY, "Failed to stat file '%s': %s", optional_string (file_name), std::strerror (errno));
 				return std::nullopt;
 			}
 
@@ -154,18 +154,30 @@ namespace xamarin::android {
 		[[gnu::flatten, gnu::always_inline]]
 		static void set_environment_variable (const char *name, const char *value) noexcept
 		{
-			log_debug (LOG_DEFAULT, "Setting environment variable {} = '{}'", optional_string (name), optional_string (value));
+			log_debugf (LOG_DEFAULT, "Setting environment variable %s = '%s'", optional_string (name), optional_string (value));
 			if (::setenv (name, value, 1) < 0) {
-				log_warn (LOG_DEFAULT, "Failed to set environment variable '{}': {}", name, ::strerror (errno));
+				log_warnf (LOG_DEFAULT, "Failed to set environment variable '%s': %s", optional_string (name), ::strerror (errno));
 			}
 		}
 
 		[[gnu::flatten, gnu::always_inline]]
 		static void set_environment_variable_if_unset (std::string_view const& name, jstring_wrapper& value) noexcept
 		{
-			log_debug (LOG_DEFAULT, "Setting environment variable {} = '{}' if unset", name, value.get_string_view ());
+			log_debugf (
+				LOG_DEFAULT,
+				"Setting environment variable %.*s = '%s' if unset",
+				static_cast<int>(name.length ()),
+				name.data (),
+				optional_string (value.get_cstr ())
+			);
 			if (::setenv (name.data (), value.get_cstr (), 0) < 0) {
-				log_warn (LOG_DEFAULT, "Failed to set environment variable '{}': {}", name, ::strerror (errno));
+				log_warnf (
+					LOG_DEFAULT,
+					"Failed to set environment variable '%.*s': %s",
+					static_cast<int>(name.length ()),
+					name.data (),
+					::strerror (errno)
+				);
 			}
 		}
 
@@ -187,7 +199,14 @@ namespace xamarin::android {
 			if (createDirectory) {
 				int rv = create_directory (value.get_cstr (), mode);
 				if (rv < 0 && errno != EEXIST) {
-					log_warn (LOG_DEFAULT, "Failed to create directory '{}' for environment variable '{}'. {}", value.get_string_view (), name, strerror (errno));
+					log_warnf (
+						LOG_DEFAULT,
+						"Failed to create directory '%s' for environment variable '%.*s'. %s",
+						optional_string (value.get_cstr ()),
+						static_cast<int>(name.length ()),
+						name.data (),
+						strerror (errno)
+					);
 				}
 			}
 			set_environment_variable (name, value);
@@ -217,32 +236,33 @@ namespace xamarin::android {
 			mmap_info.area		  = mmap (nullptr, offsetSize, PROT_READ, MAP_PRIVATE, fd, static_cast<off_t>(offsetPage));
 
 			if (mmap_info.area == MAP_FAILED) {
-				Helpers::abort_application (
+				Helpers::abort_applicationf (
 					LOG_ASSEMBLY,
-					std::format (
-						"Could not mmap APK fd {}: {}; File={}",
-						fd,
-						strerror (errno),
-						filename
-					)
+					std::source_location::current (),
+					"Could not mmap APK fd %d: %s; File=%.*s",
+					fd,
+					strerror (errno),
+					static_cast<int>(filename.length ()),
+					filename.data ()
 				);
 			}
 
 			mmap_info.size = offsetSize;
 			file_info.area = pointer_add (mmap_info.area, offsetFromPage);
 			file_info.size = size;
 
-			log_info (
+			log_infof (
 				LOG_ASSEMBLY,
-				"  mmap_start: {:<8p}; mmap_end: {:<8p}	 mmap_len: {:<12}  file_start: {:<8p}  file_end: {:<8p}	 file_len: {:<12}	  apk descriptor: {}  file: {}",
+				"  mmap_start: %p; mmap_end: %p\t mmap_len: %zu  file_start: %p  file_end: %p\t file_len: %zu\t  apk descriptor: %d  file: %.*s",
 				mmap_info.area,
 				pointer_add (mmap_info.area, mmap_info.size),
 				mmap_info.size,
 				file_info.area,
 				pointer_add (file_info.area, file_info.size),
 				file_info.size,
 				fd,
-				filename
+				static_cast<int>(filename.length ()),
+				filename.data ()
 			);
 
 			return file_info;
@@ -265,7 +285,12 @@ namespace xamarin::android {
 					elf_header->e_ident[EI_MAG1] != ELFMAG1 ||
 					elf_header->e_ident[EI_MAG2] != ELFMAG2 ||
 					elf_header->e_ident[EI_MAG3] != ELFMAG3) {
-						log_debug (LOG_ASSEMBLY, "Not an ELF image: {}", file_name);
+						log_debugf (
+							LOG_ASSEMBLY,
+							"Not an ELF image: %.*s",
+							static_cast<int>(file_name.length ()),
+							file_name.data ()
+						);
 						// Not an ELF image, just return what we mmapped before
 						return { map_info.area, map_info.size };
 				}

src/native/clr/include/shared/log_types.hh

@@ -1,5 +1,6 @@
 #pragma once
 
+#include <cstdarg>
 #include <cstdint>
 #include <format>
 #include <string>
@@ -47,6 +48,12 @@ namespace xamarin::android {
 	// A slightly faster alternative to other log functions as it doesn't parse the message
 	// for format placeholders nor it uses variable arguments
 	void log_write (LogCategories category, LogLevel level, const char *message) noexcept;
+	void log_writev (LogCategories category, LogLevel level, const char *format, va_list args) noexcept;
+	void log_writef (LogCategories category, LogLevel level, const char *format, ...) noexcept __attribute__ ((format (printf, 3, 4)));
+	void log_debugf (LogCategories category, const char *format, ...) noexcept __attribute__ ((format (printf, 2, 3)));
+	void log_infof (LogCategories category, const char *format, ...) noexcept __attribute__ ((format (printf, 2, 3)));
+	void log_warnf (LogCategories category, const char *format, ...) noexcept __attribute__ ((format (printf, 2, 3)));
+	void log_errorf (LogCategories category, const char *format, ...) noexcept __attribute__ ((format (printf, 2, 3)));
 
 	[[gnu::always_inline]]
 	static inline void log_write (LogCategories category, LogLevel level, std::string_view const& message) noexcept

src/native/clr/runtime-base/android-system-shared.cc

@@ -36,7 +36,7 @@ AndroidSystem::monodroid__system_property_get (std::string_view const& name, cha
 	char *buf = nullptr;
 	if (sp_value_len < Constants::PROPERTY_VALUE_BUFFER_LEN) {
 		size_t alloc_size = Helpers::add_with_overflow_check<size_t> (Constants::PROPERTY_VALUE_BUFFER_LEN, 1uz);
-		log_warn (LOG_DEFAULT, "Buffer to store system property may be too small, will copy only {} bytes", sp_value_len);
+		log_warnf (LOG_DEFAULT, "Buffer to store system property may be too small, will copy only %zu bytes", sp_value_len);
 		buf = new char [alloc_size];
 	}
 
@@ -81,10 +81,16 @@ AndroidSystem::get_max_gref_count_from_system () noexcept -> long
 		}
 
 		if (*e) {
-			log_warn (LOG_GC, "Unsupported '{}' value '{}'.", Constants::DEBUG_MONO_MAX_GREFC.data (), override.get ());
+			log_warnf (
+				LOG_GC,
+				"Unsupported '%.*s' value '%s'.",
+				static_cast<int>(Constants::DEBUG_MONO_MAX_GREFC.length ()),
+				Constants::DEBUG_MONO_MAX_GREFC.data (),
+				override.get ()
+			);
 		}
 
-		log_warn (LOG_GC, "Overriding max JNI Global Reference count to {}", max);
+		log_warnf (LOG_GC, "Overriding max JNI Global Reference count to %ld", max);
 	}
 
 	return max;

src/native/clr/runtime-base/util.cc

@@ -58,7 +58,13 @@ Util::create_public_directory (std::string_view const& dir)
 			// Try to change the mode, just in case
 			chmod (dir.data (), 0777);
 		} else {
-			log_warn (LOG_DEFAULT, "Failed to create directory '{}'. {}"sv, dir, std::strerror (errno));
+			log_warnf (
+				LOG_DEFAULT,
+				"Failed to create directory '%.*s'. %s",
+				static_cast<int>(dir.length ()),
+				dir.data (),
+				std::strerror (errno)
+			);
 		}
 	}
 	umask (m);
@@ -72,7 +78,13 @@ Util::monodroid_fopen (std::string_view const& filename, std::string_view const&
 	 */
 	FILE *ret = fopen (filename.data (), mode.data ());
 	if (ret == nullptr) {
-		log_error (LOG_DEFAULT, "fopen failed for file {}: {}", filename, strerror (errno));
+		log_errorf (
+			LOG_DEFAULT,
+			"fopen failed for file %.*s: %s",
+			static_cast<int>(filename.length ()),
+			filename.data (),
+			strerror (errno)
+		);
 		return nullptr;
 	}
 
@@ -87,7 +99,13 @@ void Util::set_world_accessable (std::string_view const& path)
 	} while (r == -1 && errno == EINTR);
 
 	if (r == -1) {
-		log_error (LOG_DEFAULT, "chmod(\"{}\", 0664) failed: {}", path, strerror (errno));
+		log_errorf (
+			LOG_DEFAULT,
+			"chmod(\"%.*s\", 0664) failed: %s",
+			static_cast<int>(path.length ()),
+			path.data (),
+			strerror (errno)
+		);
 	}
 }
 
@@ -99,7 +117,7 @@ auto Util::set_world_accessible (int fd) noexcept -> bool
 	} while (r == -1 && errno == EINTR);
 
 	if (r == -1) {
-		log_error (LOG_DEFAULT, "fchmod() failed: {}"sv, strerror (errno));
+		log_errorf (LOG_DEFAULT, "fchmod() failed: %s", strerror (errno));
 		return false;
 	}
 

src/native/clr/shared/helpers.cc

@@ -1,4 +1,5 @@
 #include <cstdarg>
+#include <cstdio>
 #include <cstring>
 #include <android/set_abort_message.h>
 
@@ -7,11 +8,24 @@
 
 using namespace xamarin::android;
 
+[[noreturn]] void
+Helpers::abort_applicationf (LogCategories category, std::source_location sloc, const char *format, ...) noexcept
+{
+	char *message = nullptr;
+	const char *safe_format = format == nullptr ? "<null>" : format;
+	va_list args;
+	va_start (args, format);
+	int ret = vasprintf (&message, safe_format, args);
+	va_end (args);
+
+	abort_application (category, ret < 0 ? safe_format : message, true, sloc);
+}
+
 [[noreturn]] void
 Helpers::abort_application (LogCategories category, const char *message, bool log_location, std::source_location sloc) noexcept
 {
 	// Log it, but also...
-	log_fatal (category, "{}", message);
+	log_write (category, LogLevel::Fatal, message);
 
 	// ...let android include it in the tombstone, debuggerd output, stack trace etc
 	android_set_abort_message (message);
@@ -33,9 +47,10 @@ Helpers::abort_application (LogCategories category, const char *message, bool lo
 			}
 		}
 
-		log_fatal (
+		log_writef (
 			category,
-			"Abort at {}:{}:{} ('{}')",
+			LogLevel::Fatal,
+			"Abort at %s:%u:%u ('%s')",
 			file_name,
 			sloc.line (),
 			sloc.column (),

src/native/clr/shared/log_functions.cc

@@ -55,6 +55,17 @@ namespace {
 	};
 
 	constexpr size_t loglevel_map_max_index = (sizeof(loglevel_map) / sizeof(android_LogPriority)) - 1;
+
+	[[gnu::always_inline]]
+	auto priority_for_level (LogLevel level) noexcept -> android_LogPriority
+	{
+		size_t map_index = static_cast<size_t>(level);
+		if (map_index > loglevel_map_max_index) {
+			return DEFAULT_PRIORITY;
+		}
+
+		return loglevel_map[map_index];
+	}
 }
 
 unsigned int log_categories = LOG_NONE;
@@ -117,15 +128,67 @@ namespace xamarin::android {
 	void
 	log_write (LogCategories category, LogLevel level, const char *message) noexcept
 	{
-		size_t map_index = static_cast<size_t>(level);
-		android_LogPriority priority;
+		__android_log_write (priority_for_level (level), category_name (category), message);
+	}
 
-		if (map_index > loglevel_map_max_index) {
-			priority = DEFAULT_PRIORITY;
-		} else {
-			priority = loglevel_map[map_index];
+	void
+	log_writev (LogCategories category, LogLevel level, const char *format, va_list args) noexcept
+	{
+		const char *safe_format = format == nullptr ? "<null>" : format;
+		__android_log_vprint (priority_for_level (level), category_name (category), safe_format, args);
+	}
+
+	void
+	log_writef (LogCategories category, LogLevel level, const char *format, ...) noexcept
+	{
+		va_list args;
+		va_start (args, format);
+		log_writev (category, level, format, args);
+		va_end (args);
+	}
+
+	void
+	log_debugf (LogCategories category, const char *format, ...) noexcept
+	{
+		if ((log_categories & category) == 0) {
+			return;
+		}
+
+		va_list args;
+		va_start (args, format);
+		log_writev (category, LogLevel::Debug, format, args);
+		va_end (args);
+	}
+
+	void
+	log_infof (LogCategories category, const char *format, ...) noexcept
+	{
+		if ((log_categories & category) == 0) {
+			return;
 		}
 
-		__android_log_write (priority, category_name (category), message);
+		va_list args;
+		va_start (args, format);
+		log_writev (category, LogLevel::Info, format, args);
+		va_end (args);
 	}
+
+	void
+	log_warnf (LogCategories category, const char *format, ...) noexcept
+	{
+		va_list args;
+		va_start (args, format);
+		log_writev (category, LogLevel::Warn, format, args);
+		va_end (args);
+	}
+
+	void
+	log_errorf (LogCategories category, const char *format, ...) noexcept
+	{
+		va_list args;
+		va_start (args, format);
+		log_writev (category, LogLevel::Error, format, args);
+		va_end (args);
+	}
+
 }

src/native/common/include/shared/helpers.hh

@@ -56,6 +56,9 @@ namespace xamarin::android
 		[[noreturn]]
 		static void abort_application (LogCategories category, const char *message, bool log_location = true, std::source_location sloc = std::source_location::current ()) noexcept;
 
+		[[noreturn]]
+		static void abort_applicationf (LogCategories category, std::source_location sloc, const char *format, ...) noexcept __attribute__ ((format (printf, 3, 4)));
+
 		[[noreturn]]
 		static void abort_application (LogCategories category, std::string const& message, bool log_location = true, std::source_location sloc = std::source_location::current ()) noexcept
 		{