add signal api

headers/signal.h

@@ -1,9 +1,12 @@
 #pragma once
 
-#define SIG_DFL -1
+#include <stdbool.h>
-#define SIG_IGN 0
+#include <stdint.h>
 
-enum {
+#define SIG_DFL 0
+#define SIG_IGN -1
+
+typedef enum {
 	SIGABRT,   // Abort signal from abort(3)
 	SIGALRM,   // Timer signal from alarm(2)
 	SIGBUS,    // Bus error (bad memory access)
@@ -44,11 +47,16 @@ enum {
 	SIGXFSZ,   // File size limit exceeded (4.2BSD); see setrlimit(2)
 	SIGWINCH,  // Window resize signal (4.3BSD, Sun)
 	SIG_INT,   // Interrupt from keyboard
-};
+	LAST
+} SIGNAL_CODE;
 
-typedef void (*sighandler_t)(int);
+typedef void (*signal_handler_t)(int);
 
-struct signal {
+void signal(SIGNAL_CODE sig_num, void *handler);
-	int signum;
+void kill(int pid, SIGNAL_CODE sig_num);
-	sighandler_t handler;
+void exec_signal_pending(void);
+
+struct signal_data {
+	void *handlers[LAST];
+	uint32_t pending;
 };

headers/task.h

@@ -2,6 +2,7 @@
 
 #include "list.h"
 #include "memory.h"
+#include "signal.h"
 
 #include <stdint.h>
 
@@ -23,7 +24,7 @@ struct task {
 	uint8_t uid;
 	struct task *daddy;
 	struct task *child;
-	struct list **signals;
+	struct signal_data signals;
 	struct task *next;
 	struct task *prev;
 };

src/drivers/clock.c

@@ -38,7 +38,7 @@ void clock_init(struct registers *regs)
 static void clock_handler(struct registers *regs)
 {
 	(void)regs;
-	if (scheduler_counter % 100 == 0)
+	if (scheduler_counter % 10 == 0)
 		scheduler();
 	scheduler_counter++;
 	sleep_counter--;

src/interrupt/signals/signal.c

@@ -1,10 +0,0 @@
-#include "signal.h"
-#include <stddef.h>
-
-void (*signal(int sig, void (*func)(int)))(int)
-{
-	// TODO after multi tasking and processes
-	(void)sig;
-	(void)func;
-	return NULL;
-}

src/kernel.c

@@ -52,6 +52,11 @@ static void awa(void)
 		wait();
 }
 
+static void bozo(int int_code)
+{
+	kprintf("apagnan code\n");
+}
+
 void kernel_main(multiboot_info_t *mbd, uint32_t magic)
 {
 	terminal_initialize();
@@ -79,5 +84,10 @@ void kernel_main(multiboot_info_t *mbd, uint32_t magic)
 	// exec_fn(owo);
 	// exec_fn(owo);
 	// exec_fn(owo);
+	kill(0, 4);
+	for (size_t i = 0; i < 10000; i++)
+		free_pages(alloc_pages(1, NULL), 1);
+	signal(4, bozo);
+	kill(0, 4);
 	shell_init();
 }

src/multitasking/scheduler.c

@@ -30,5 +30,6 @@ void scheduler(void)
 		it = it->next;
 	}
 	switch_to_task(it);
+	exec_signal_pending();
 	toris();
 }

src/multitasking/task.c

@@ -49,6 +49,9 @@ struct task *create_task(uint8_t uid)
 	new_task->next = current_task->next;
 	new_task->prev = current_task;
 	current_task->next = new_task;
+
+	new_task->signals.pending = SIG_IGN;
+
 	return new_task;
 }
 
@@ -64,6 +67,7 @@ int8_t create_kernel_task(void)
 	new_task->cr3 = (uint32_t *)((uint32_t)kernel_pd - HEAP_END);
 	new_task->prev = new_task;
 	new_task->next = new_task;
+	new_task->signals.pending = SIG_IGN;
 	current_task = new_task;
 	return 0;
 }

src/signal/signal.c

@@ -0,0 +1,49 @@
+#include "signal.h"
+#include "kprintf.h"
+#include "task.h"
+#include <stdint.h>
+
+void signal(SIGNAL_CODE sig_num, void *handler)
+{
+	current_task->signals.handlers[sig_num] = handler;
+}
+
+void kill(int pid, SIGNAL_CODE sig_num)
+{
+	struct task *task = current_task;
+
+	while (task->pid != pid)
+		task = task->next;
+
+	task->signals.pending = sig_num;
+}
+
+static void display_signal(SIGNAL_CODE sig_num)
+{
+	kprintf("signal: %d\n", sig_num);
+}
+
+static void exec_signal(SIGNAL_CODE sig_num)
+{
+	void *handler = current_task->signals.handlers[sig_num];
+
+	if (handler == SIG_IGN)
+		return;
+
+	if (handler == SIG_DFL) {
+		display_signal(sig_num);
+		return;
+	}
+
+	signal_handler_t func = handler;
+	func(sig_num);
+}
+
+void exec_signal_pending(void)
+{
+	uint32_t signal_code = current_task->signals.pending;
+	if (signal_code != SIG_IGN) {
+		exec_signal(signal_code);
+		current_task->signals.pending = SIG_IGN;
+	}
+}