Kernel: Changed serial debug functions and variables for readability

Change the name of set_serial_debug(bool on_or_off) to
set_serial_debug_enabled(bool desired_state). This is to make the names
more expressive and less unclear as to what the function does, as it
only sets the enabled state.
Likewise, change the name of get_serial_debug() to
is_serial_debug_enabled() in order to make clear from the name that
this is simply the state of s_serial_debug_enabled.
Change the name of serial_debug to s_serial_debug_enabled since this is
a static bool describing this state.
Finally, change the signature of set_serial_debug_enabled to return a
bool, as this is more logical and understandable.

Kernel/init.cpp

@@ -319,7 +319,7 @@ void init_stage2(void*)
 
     VirtualFileSystem::initialize();
 
-    if (!get_serial_debug())
+    if (!is_serial_debug_enabled())
         (void)SerialDevice::must_create(0).leak_ref();
     (void)SerialDevice::must_create(1).leak_ref();
     (void)SerialDevice::must_create(2).leak_ref();
@@ -409,7 +409,7 @@ UNMAP_AFTER_INIT void setup_serial_debug()
     // 8-N-1 57600 baud. this is particularly useful for debugging the boot
     // process on live hardware.
     if (StringView { kernel_cmdline, strlen(kernel_cmdline) }.contains("serial_debug"sv)) {
-        set_serial_debug(true);
+        set_serial_debug_enabled(true);
     }
 }
 

Kernel/kprintf.cpp

@@ -23,19 +23,19 @@ namespace Kernel {
 extern Atomic<Graphics::Console*> g_boot_console;
 }
 
-static bool serial_debug;
+static bool s_serial_debug_enabled;
 // A recursive spinlock allows us to keep writing in the case where a
 // page fault happens in the middle of a dbgln(), etc
 static RecursiveSpinlock s_log_lock { LockRank::None };
 
-void set_serial_debug(bool on_or_off)
+void set_serial_debug_enabled(bool desired_state)
 {
-    serial_debug = on_or_off;
+    s_serial_debug_enabled = desired_state;
 }
 
-int get_serial_debug()
+bool is_serial_debug_enabled()
 {
-    return serial_debug;
+    return s_serial_debug_enabled;
 }
 
 static void serial_putch(char ch)
@@ -71,7 +71,7 @@ static void serial_putch(char ch)
 
 static void critical_console_out(char ch)
 {
-    if (serial_debug)
+    if (s_serial_debug_enabled)
         serial_putch(ch);
     // No need to output things to the real ConsoleDevice as no one is likely
     // to read it (because we are in a fatal situation, so only print things and halt)
@@ -87,7 +87,7 @@ static void critical_console_out(char ch)
 
 static void console_out(char ch)
 {
-    if (serial_debug)
+    if (s_serial_debug_enabled)
         serial_putch(ch);
 
     // It would be bad to reach the assert in ConsoleDevice()::the() and do a stack overflow
@@ -151,7 +151,7 @@ int snprintf(char* buffer, size_t size, char const* fmt, ...)
 
 static inline void internal_dbgputch(char ch)
 {
-    if (serial_debug)
+    if (s_serial_debug_enabled)
         serial_putch(ch);
     IO::out8(IO::BOCHS_DEBUG_PORT, ch);
 }

Kernel/kstdio.h

@@ -15,8 +15,8 @@ void kernelputstr(char const*, size_t);
 void kernelcriticalputstr(char const*, size_t);
 void kernelearlyputstr(char const*, size_t);
 int snprintf(char* buf, size_t, char const* fmt, ...) __attribute__((format(printf, 3, 4)));
-void set_serial_debug(bool on_or_off);
-int get_serial_debug();
+void set_serial_debug_enabled(bool desired_state);
+bool is_serial_debug_enabled();
 }
 
 void dbgputstr(StringView view);