From 6307b0168978f7df99a7ea747c00f8e9c7624a39 Mon Sep 17 00:00:00 2001
From: apio <blobs.trading@gmail.com>
Date: Sat, 13 May 2023 16:34:18 +0200
Subject: [PATCH] kernel/ATA: Read ATA strings properly instead of backwards

Now we can see the model string. What does it say...

"QEMU DVD-ROM". Let's go!
---
 kernel/src/arch/x86_64/disk/ATA.cpp | 20 +++++++++++++++++---
 libluna/include/luna/StaticString.h | 10 ++++++++++
 2 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/kernel/src/arch/x86_64/disk/ATA.cpp b/kernel/src/arch/x86_64/disk/ATA.cpp
index 5f84bd68..4229322c 100644
--- a/kernel/src/arch/x86_64/disk/ATA.cpp
+++ b/kernel/src/arch/x86_64/disk/ATA.cpp
@@ -12,6 +12,20 @@ static void irq_handler(Registers* regs, void* ctx)
     ((ATA::Channel*)ctx)->irq_handler(regs);
 }
 
+static usize copy_ata_string(char* out, u16* in, usize size)
+{
+    for (usize i = 0; i < size; i += 2)
+    {
+        u16 val = in[i / 2];
+        out[i] = (u8)(val >> 8);
+        out[i + 1] = (u8)(val & 0xff);
+    }
+
+    out[size + 1] = '\0';
+
+    return size;
+}
+
 namespace ATA
 {
     Result<void> Controller::scan()
@@ -275,9 +289,9 @@ namespace ATA
 
         if (!identify_ata()) return false;
 
-        m_serial = StringView::from_fixed_size_cstring((const char*)&m_identify_words[10], SERIAL_LEN);
-        m_revision = StringView::from_fixed_size_cstring((const char*)&m_identify_words[23], REVISION_LEN);
-        m_model = StringView::from_fixed_size_cstring((const char*)&m_identify_words[27], MODEL_LEN);
+        m_serial.set_length(copy_ata_string(m_serial.data(), &m_identify_words[10], SERIAL_LEN));
+        m_revision.set_length(copy_ata_string(m_revision.data(), &m_identify_words[23], REVISION_LEN));
+        m_model.set_length(copy_ata_string(m_model.data(), &m_identify_words[27], MODEL_LEN));
 
         m_serial.trim(" ");
         m_revision.trim(" ");
diff --git a/libluna/include/luna/StaticString.h b/libluna/include/luna/StaticString.h
index cc1835fd..33e79b11 100644
--- a/libluna/include/luna/StaticString.h
+++ b/libluna/include/luna/StaticString.h
@@ -62,6 +62,16 @@ template <usize Size> class StaticString
         return m_buffer;
     }
 
+    char* data()
+    {
+        return m_buffer;
+    }
+
+    void set_length(usize len)
+    {
+        m_length = len;
+    }
+
     usize length() const
     {
         return m_length;