From 5d4454e57ab22ff1c4010748ac02e5f1ee1284b5 Mon Sep 17 00:00:00 2001
From: Xnoe <xnoe@xnoe.moe>
Date: Sat, 27 Nov 2021 15:56:35 +0000
Subject: [PATCH] Remove debug code from terminal.cpp. Update kmain, update
 world.c, update process.cpp to construct the initial value of EBP correctly.

---
 src/kernel/idt.cpp      | 8 ++++----
 src/kernel/kmain.cpp    | 2 +-
 src/kernel/process.cpp  | 4 +++-
 src/kernel/process.h    | 3 +--
 src/kernel/terminal.cpp | 4 +---
 src/program/world.c     | 7 ++++++-
 6 files changed, 16 insertions(+), 12 deletions(-)

diff --git a/src/kernel/idt.cpp b/src/kernel/idt.cpp
index 78789a8..62b4208 100644
--- a/src/kernel/idt.cpp
+++ b/src/kernel/idt.cpp
@@ -73,11 +73,11 @@ __attribute__((interrupt)) void context_switch(interrupt_frame* frame) {
         processes->start->next->prev = processes->start;
         processes->end->prev->next = processes->end;
       }
-
-      // Get the next process.
-      nextProc = processes->start->elem;
     }
 
+    // Get the next process.
+    nextProc = processes->start->elem;
+
     Global::currentProc = nextProc;
 
     uint32_t cESP;
@@ -94,7 +94,7 @@ __attribute__((interrupt)) void context_switch(interrupt_frame* frame) {
     asm ("popa"); 
     
     // Clear the garbage that was on the stack from previous switch_context call.
-    asm ("add $84, %esp");
+    asm ("mov %ebp, %esp");
 
     // Pop EBP
     asm ("pop %ebp");
diff --git a/src/kernel/kmain.cpp b/src/kernel/kmain.cpp
index 1e8be37..569169e 100644
--- a/src/kernel/kmain.cpp
+++ b/src/kernel/kmain.cpp
@@ -47,7 +47,7 @@ int main() {
   Global::currentProc = &kernel;
 
   Process* p1 = kernel.createProcess("WORLD   BIN");
-  Process* p2 = kernel.createProcess("HELLO   BIN");
+  //Process* p2 = kernel.createProcess("HELLO   BIN");
 
   init_keyboard();
   
diff --git a/src/kernel/process.cpp b/src/kernel/process.cpp
index e1c7ea9..d428013 100644
--- a/src/kernel/process.cpp
+++ b/src/kernel/process.cpp
@@ -59,6 +59,8 @@ Process::Process(uint32_t PID, PageDirectory* inherit, uint32_t inheritBase, cha
   stack32--;
   *stack32 = ((uint32_t)this->stack + 0x8000); // EBP
 
+  uint32_t rEBP = stack32;
+
   stack32 -= 21;
 
   stack32--;
@@ -72,7 +74,7 @@ Process::Process(uint32_t PID, PageDirectory* inherit, uint32_t inheritBase, cha
   stack32--;
   *stack32 = 0; // ESP
   stack32--;
-  *stack32 = (uint32_t)this->stack + 0x7ffc; // EBP
+  *stack32 = rEBP; // EBP
   stack32--;
   *stack32 = 0; // ESI
   stack32--;
diff --git a/src/kernel/process.h b/src/kernel/process.h
index af969e1..c2fd0ee 100644
--- a/src/kernel/process.h
+++ b/src/kernel/process.h
@@ -20,8 +20,6 @@ struct AllocTracker {
 
 class Process : public Allocator {
 private:
-  uint32_t PID;
-
   uint32_t last_page_pointer;
   uint32_t page_remaining;
 
@@ -33,6 +31,7 @@ private:
   xnoe::Maybe<xnoe::linkedlistelem<AllocTracker>*> get_alloc_tracker(uint32_t address);
 
 public:
+  uint32_t PID;
   uint32_t esp;
 
   Process(uint32_t PID, void* stack, PageDirectory* page_directory, PageMap* phys, PageMap* virt, uint32_t virt_alloc_base);
diff --git a/src/kernel/terminal.cpp b/src/kernel/terminal.cpp
index d329d56..52bfe59 100644
--- a/src/kernel/terminal.cpp
+++ b/src/kernel/terminal.cpp
@@ -63,10 +63,8 @@ void Terminal::printf(const char* string, ...) {
       this->cur_y++;
     }
 
-    if (this->cur_y == this->height) {
+    if (this->cur_y == this->height)
       this->scroll_up();
-      printf("This gets called...");
-    }
 
     if (current == '%') {
       int type = string[index++];
diff --git a/src/program/world.c b/src/program/world.c
index 8603aae..df5d5b4 100644
--- a/src/program/world.c
+++ b/src/program/world.c
@@ -1,7 +1,12 @@
 #include "../common/common.h"
 
 int main() {
+  char buffer[2];
+  buffer[0] = 0;
+  buffer[1] = 0;
+
   while (1) {
-    print("World");
+    buffer[0] = getch();
+    print(buffer);
   }
 }
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