Make log __attribute__(format), so the compiler can warn us of bad format strings

kernel/src/Log.cpp

@@ -14,11 +14,17 @@ static constexpr u32 WHITE = 0xffffffff;
 static constexpr u32 YELLOW = 0xffffff00;
 static constexpr u32 RED = 0xffff0000;
 
-static Result<void> log_serial(LogLevel, const char* format, va_list origin)
+static char log_level_letters[] = {'D', 'I', 'W', 'E'}; // D for debug, I for info, W for warning, E for error
+static const char* ansi_color_codes_per_log_level[] = {"37", "37", "33", "31"}; // 37 is white, 33 yellow, 31 red
+
+static Result<void> log_serial(LogLevel level, const char* format, va_list origin)
 {
     va_list ap;
     va_copy(ap, origin);
 
+    TRY(Serial::printf("\x1b[%sm%c\x1b[0m ", ansi_color_codes_per_log_level[(int)level],
+                       log_level_letters[(int)level]));
+
     TRY(Serial::printf("[%6zu.%.6zu] ", Timer::ticks(), Timer::ticks_us() - (Timer::ticks() * 1000000)));
 
     TRY(cstyle_format(

kernel/src/Log.h

@@ -1,4 +1,5 @@
 #pragma once
+#include <Attributes.h>
 #include <Result.h>
 #include <stdarg.h>
 
@@ -11,7 +12,7 @@ enum class LogLevel
 };
 
 Result<void> vlog(LogLevel level, const char* format, va_list ap);
-Result<void> log(LogLevel level, const char* format, ...);
+Result<void> log(LogLevel level, const char* format, ...) _format(2, 3);
 
 void setup_log(bool enable_debug, bool enable_serial, bool enable_text_console);
 bool log_debug_enabled();

kernel/src/main.cpp

@@ -33,6 +33,10 @@ Result<void> init()
     to_dynamic_unit(MemoryManager::reserved(), buffer, sizeof(buffer));
     kinfoln("Reserved memory: %s", buffer);
 
+    volatile char* p = (volatile char*)0xefe0f3445692d;
+
+    *p = 7;
+
     return {};
 }