Add unit formatting

kernel/src/main.cpp

@@ -6,6 +6,7 @@
 #include "memory/Heap.h"
 #include "memory/MemoryManager.h"
 #include "video/TextConsole.h"
+#include <Units.h>
 
 Result<void> init()
 {
@@ -51,6 +52,14 @@ Result<void> init()
 
     TRY(destroy(mem));
 
+    char buffer[64];
+    to_dynamic_unit(MemoryManager::free(), buffer, sizeof(buffer));
+    Serial::printf("Free memory: %s\n", buffer);
+    to_dynamic_unit(MemoryManager::used(), buffer, sizeof(buffer));
+    Serial::printf("Used memory: %s\n", buffer);
+    to_dynamic_unit(MemoryManager::reserved(), buffer, sizeof(buffer));
+    Serial::printf("Reserved memory: %s\n", buffer);
+
     while (1)
     {
         while ((Timer::ticks_ms() - start) < 20) { CPU::wait_for_interrupt(); }

luna/CMakeLists.txt

@@ -2,6 +2,7 @@ set(FREESTANDING_SOURCES
     Format.cpp
     NumberParsing.cpp
     String.cpp
+    Units.cpp
 )
 
 set(SOURCES

luna/Units.cpp

@@ -0,0 +1,17 @@
+#include <Format.h>
+#include <Units.h>
+#include <limits.h>
+
+Result<usize> to_dynamic_unit(usize value, char* buffer, size_t max)
+{
+    if (value < 1024) { return string_format(buffer, max, "%u bytes", value); }
+
+    const char* unit_prefixes = "KMGTPE";
+    for (int i = 40; i >= 0 && value > (0xfffccccccccccccUL >> i); i -= 10)
+    {
+        value >>= 10;
+        unit_prefixes++;
+    }
+
+    return string_format(buffer, max, "%u.%u %ciB", value / 1024, (value % 1024) / 103, *unit_prefixes);
+}

luna/Units.h

@@ -0,0 +1,4 @@
+#pragma once
+#include <Result.h>
+
+Result<usize> to_dynamic_unit(usize value, char* buffer, usize max);