Started multitasking

7 files changed, 99 insertions, 8 deletions

diff --git a/src/Makefile b/src/Makefile
index 37ad049..e4b11fd 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -13,6 +13,7 @@ COBJS = main.o \
 		features/psf.o \
 		features/gui.o \
 		features/load.o \
+		features/proc.o \
 		lib/str.o \
 		lib/mem.o \
 		lib/math.o \
diff --git a/src/features/load.c b/src/features/load.c
index 958acd7..2cfa546 100644
--- a/src/features/load.c
+++ b/src/features/load.c
@@ -2,15 +2,16 @@
 
 #include <def.h>
 #include <fs.h>
-#include <load.h>
+#include <mem.h>
 #include <print.h>
+#include <proc.h>
 
-void bin_load(char *path)
+void bin_load(char *path, struct proc *proc)
 {
 	char *data = read_file(path);
+	u32 stack = (u32)malloc(0x1000) + 0x1000;
 
-	void (*entry)();
-	*(void **)(&entry) = data;
-
-	entry();
+	proc->regs.ebp = stack;
+	proc->regs.esp = stack;
+	proc->regs.eip = (u32)&data;
 }
diff --git a/src/features/proc.c b/src/features/proc.c
new file mode 100644
index 0000000..92e17f1
--- /dev/null
+++ b/src/features/proc.c
@@ -0,0 +1,64 @@
+// MIT License, Copyright (c) 2020 Marvin Borner
+
+#include <interrupts.h>
+#include <load.h>
+#include <mem.h>
+#include <print.h>
+#include <proc.h>
+#include <timer.h>
+
+u32 pid = 0;
+struct proc *root;
+struct proc *current;
+struct proc *last;
+
+void scheduler(struct regs *regs)
+{
+	printf(".");
+	memcpy(&current->regs, regs, sizeof(struct regs));
+
+	timer_handler();
+
+	if (!current->next)
+		current = root;
+	else
+		current = current->next;
+
+	while (current->state == PROC_ASLEEP)
+		if (!current->next)
+			current = root;
+		else
+			current = current->next;
+
+	memcpy(regs, &current->regs, sizeof(struct regs));
+}
+
+void proc_attach(struct proc *proc)
+{
+	if (!last->next) {
+		last->next = proc;
+	} else {
+		struct proc *save = last;
+		while (save->next)
+			save = save->next;
+		save->next = proc;
+	}
+}
+
+struct proc *proc_make()
+{
+	struct proc *proc = (struct proc *)malloc(sizeof(*proc));
+	proc->pid = pid++;
+	proc->state = PROC_RUNNING;
+	if (current)
+		proc_attach(proc);
+	last = proc;
+	return proc;
+}
+
+void proc_init()
+{
+	current = root = proc_make();
+	bin_load("/root", root);
+	irq_install_handler(0, scheduler);
+}
diff --git a/src/inc/load.h b/src/inc/load.h
index a02afc0..60fecf9 100644
--- a/src/inc/load.h
+++ b/src/inc/load.h
@@ -3,6 +3,8 @@
 #ifndef LOAD_H
 #define LOAD_H
 
-void bin_load(char *path);
+#include <proc.h>
+
+void bin_load(char *path, struct proc *proc);
 
 #endif
diff --git a/src/inc/proc.h b/src/inc/proc.h
new file mode 100644
index 0000000..dc8b9e9
--- /dev/null
+++ b/src/inc/proc.h
@@ -0,0 +1,22 @@
+// MIT License, Copyright (c) 2020 Marvin Borner
+
+#ifndef PROC_H
+#define PROC_H
+
+#include <def.h>
+#include <interrupts.h>
+
+enum state { PROC_RUNNING, PROC_ASLEEP };
+
+struct proc {
+	u32 pid;
+	enum state state;
+	struct regs regs;
+	/* struct proc *parent; */
+	struct proc *next;
+};
+
+void proc_init();
+struct proc *proc_make();
+
+#endif
diff --git a/src/inc/timer.h b/src/inc/timer.h
index 4b2bb8c..7c4f077 100644
--- a/src/inc/timer.h
+++ b/src/inc/timer.h
@@ -6,5 +6,6 @@
 #include <def.h>
 
 void timer_install();
+void timer_handler(); // For scheduler
 
 #endif
diff --git a/src/main.c b/src/main.c
index ba390fa..0e08229 100644
--- a/src/main.c
+++ b/src/main.c
@@ -42,7 +42,7 @@ void kernel_main(struct mem_info *mem_info, struct vid_info *vid_info)
 	gui_init(FONT_PATH);
 
 	gui_term_write("Wake up, " USERNAME "...\n");
-	bin_load("/test");
+	proc_init();
 
 	while (1) {
 	};