Added poll syscall

8 files changed, 96 insertions, 21 deletions

diff --git a/kernel/drivers/keyboard.c b/kernel/drivers/keyboard.c
index 0dd7219..1652625 100644
--- a/kernel/drivers/keyboard.c
+++ b/kernel/drivers/keyboard.c
@@ -44,7 +44,7 @@ void keyboard_handler()
 	state = 0;
 	merged = 0;
 
-	proc_enable_waiting(dev_id);
+	proc_enable_waiting(dev_id, PROC_WAIT_DEV);
 }
 
 void keyboard_acknowledge(void)
diff --git a/kernel/drivers/mouse.c b/kernel/drivers/mouse.c
index 2e9ceae..b03ed50 100644
--- a/kernel/drivers/mouse.c
+++ b/kernel/drivers/mouse.c
@@ -6,6 +6,7 @@
 #include <interrupts.h>
 #include <mem.h>
 #include <print.h>
+#include <proc.h>
 #include <stack.h>
 #include <str.h>
 #include <sys.h>
@@ -44,8 +45,8 @@ void mouse_handler()
 		event->but2 = (mouse_byte[0] >> 1) & 1;
 		event->but3 = (mouse_byte[0] >> 2) & 1;
 		stack_push_bot(queue, event);
-
 		mouse_cycle = 0;
+		proc_enable_waiting(dev_id, PROC_WAIT_DEV);
 		break;
 	default:
 		break;
diff --git a/kernel/features/fs.c b/kernel/features/fs.c
index ecb2b85..16a12f7 100644
--- a/kernel/features/fs.c
+++ b/kernel/features/fs.c
@@ -181,6 +181,21 @@ s32 vfs_stat(const char *path, struct stat *buf)
 	return m->dev->vfs->stat(path, buf, m->dev);
 }
 
+s32 vfs_poll(const char **files)
+{
+	if (!files)
+		return -1;
+
+	for (const char **p = files; *p && **p; p++)
+		if (vfs_ready(*p))
+			return p - files;
+
+	for (const char **p = files; *p && **p; p++)
+		proc_wait_for(vfs_find_dev(*p)->id, PROC_WAIT_DEV, vfs_poll);
+
+	return PROC_MAX_WAIT_IDS + 1;
+}
+
 u8 vfs_ready(const char *path)
 {
 	while (*path == ' ')
@@ -268,6 +283,7 @@ void device_install(void)
 	struct vfs *vfs = malloc(sizeof(*vfs));
 	vfs->type = VFS_DEVFS;
 	vfs->read = devfs_read;
+	vfs->perm = devfs_perm;
 	vfs->ready = devfs_ready;
 	struct device *dev = malloc(sizeof(*dev));
 	dev->name = "dev";
diff --git a/kernel/features/proc.c b/kernel/features/proc.c
index 5dde2bd..1f402d8 100644
--- a/kernel/features/proc.c
+++ b/kernel/features/proc.c
@@ -147,22 +147,57 @@ void proc_yield(struct regs *r)
 	scheduler(r);
 }
 
-void proc_enable_waiting(u32 dev_id)
+void proc_enable_waiting(u32 id, enum proc_wait_type type)
 {
 	struct node *iterator = proc_list->head;
 	while (iterator) {
 		struct proc *p = iterator->data;
 		struct proc_wait *w = &p->wait;
-		if (p && w && w->id == dev_id) {
-			struct regs *r = &p->regs;
-			r->eax = (u32)w->func((char *)r->ebx, (void *)r->ecx, r->edx, r->esi);
-			memset(&p->wait, 0, sizeof(p->wait));
-			p->state = PROC_RUNNING;
+
+		if (!p || !w || w->id_cnt == 0 || w->type != type) {
+			iterator = iterator->next;
+			continue;
+		}
+
+		u8 dispatched = 0;
+
+		for (u32 i = 0; i < PROC_MAX_WAIT_IDS; i++) {
+			if (w->ids[i] == id) {
+				struct regs *r = &p->regs;
+				if (w->func)
+					r->eax = (u32)w->func((char *)r->ebx, (void *)r->ecx,
+							      r->edx, r->esi);
+				w->ids[i] = 0;
+				p->state = PROC_RUNNING;
+				dispatched = 1;
+				break;
+			}
 		}
+
+		if (dispatched)
+			memset(&p->wait, 0, sizeof(p->wait));
+
 		iterator = iterator->next;
 	}
 }
 
+void proc_wait_for(u32 id, enum proc_wait_type type, s32 (*func)())
+{
+	struct proc *p = proc_current();
+
+	if (p->wait.id_cnt > 0) {
+		p->wait.ids[p->wait.id_cnt++] = id;
+		assert(func == p->wait.func && type == p->wait.type);
+	} else {
+		p->wait.type = type;
+		p->wait.id_cnt = 1;
+		p->wait.ids[0] = id;
+		p->wait.func = func;
+	}
+
+	p->state = PROC_SLEEPING;
+}
+
 struct proc *proc_make(void)
 {
 	struct proc *proc = malloc(sizeof(*proc));
@@ -170,6 +205,8 @@ struct proc *proc_make(void)
 	proc->super = 0;
 	proc->messages = stack_new();
 	proc->state = PROC_RUNNING;
+	proc->wait.id_cnt = 0;
+	proc->wait.func = NULL;
 
 	if (current)
 		list_add(proc_list, proc);
@@ -261,9 +298,12 @@ s32 procfs_read(const char *path, void *buf, u32 offset, u32 count, struct devic
 u8 procfs_perm(const char *path, enum vfs_perm perm, struct device *dev)
 {
 	(void)path;
-	(void)perm;
 	(void)dev;
-	return 1;
+
+	if (perm == VFS_EXEC)
+		return 0;
+	else
+		return 1;
 }
 
 u8 procfs_ready(const char *path, struct device *dev)
@@ -290,6 +330,7 @@ void proc_init(void)
 	vfs->type = VFS_PROCFS;
 	vfs->read = procfs_read;
 	vfs->write = procfs_write;
+	vfs->perm = procfs_perm;
 	vfs->ready = procfs_ready;
 	vfs->data = NULL;
 	struct device *dev = malloc(sizeof(*dev));
diff --git a/kernel/features/syscall.c b/kernel/features/syscall.c
index d980317..8140313 100644
--- a/kernel/features/syscall.c
+++ b/kernel/features/syscall.c
@@ -12,6 +12,14 @@
 #include <sys.h>
 #include <timer.h>
 
+void syscall_yield(struct regs *r)
+{
+	proc_yield(r);
+	sti();
+	while (1)
+		hlt();
+}
+
 void syscall_handler(struct regs *r)
 {
 	enum sys num = r->eax;
@@ -40,14 +48,8 @@ void syscall_handler(struct regs *r)
 		if (vfs_ready((char *)r->ebx)) {
 			r->eax = (u32)vfs_read((char *)r->ebx, (void *)r->ecx, r->edx, r->esi);
 		} else {
-			struct proc *p = proc_current();
-			p->state = PROC_SLEEPING;
-			p->wait.id = vfs_find_dev((char *)r->ebx)->id;
-			p->wait.func = vfs_read;
-			proc_yield(r);
-			sti();
-			while (1)
-				hlt();
+			proc_wait_for(vfs_find_dev((char *)r->ebx)->id, PROC_WAIT_DEV, vfs_read);
+			syscall_yield(r);
 		}
 		break;
 	}
@@ -55,6 +57,14 @@ void syscall_handler(struct regs *r)
 		r->eax = (u32)vfs_write((char *)r->ebx, (void *)r->ecx, r->edx, r->esi);
 		break;
 	}
+	case SYS_POLL: {
+		s32 ret = vfs_poll((const char **)r->ebx);
+		if (ret == PROC_MAX_WAIT_IDS + 1)
+			syscall_yield(r);
+		else
+			r->eax = ret;
+		break;
+	}
 	case SYS_EXEC: {
 		char *path = (char *)r->ebx;
 		struct proc *proc = proc_make();
diff --git a/kernel/inc/fs.h b/kernel/inc/fs.h
index 1069597..1f46ba3 100644
--- a/kernel/inc/fs.h
+++ b/kernel/inc/fs.h
@@ -60,6 +60,7 @@ struct device *vfs_find_dev(const char *path);
 s32 vfs_read(const char *path, void *buf, u32 offset, u32 count);
 s32 vfs_write(const char *path, void *buf, u32 offset, u32 count);
 s32 vfs_stat(const char *path, struct stat *buf);
+s32 vfs_poll(const char **files);
 u8 vfs_ready(const char *path);
 
 struct device *device_get_by_name(const char *name);
diff --git a/kernel/inc/proc.h b/kernel/inc/proc.h
index 4a75638..0007744 100644
--- a/kernel/inc/proc.h
+++ b/kernel/inc/proc.h
@@ -17,10 +17,15 @@
 #define GDT_USER_CODE_OFFSET 0x1b // User code segment offset in GDT (with ring3 mask)
 #define GDT_USER_DATA_OFFSET 0x23 // User data segment offset in GDT (with ring3 mask)
 
+#define PROC_MAX_WAIT_IDS 16
+
 enum proc_state { PROC_RUNNING, PROC_SLEEPING };
+enum proc_wait_type { PROC_WAIT_DEV };
 
 struct proc_wait {
-	u32 id; // dev_id
+	enum proc_wait_type type;
+	u32 ids[PROC_MAX_WAIT_IDS]; // dev_id
+	u32 id_cnt;
 	s32 (*func)();
 };
 
@@ -43,7 +48,8 @@ struct proc *proc_from_pid(u32 pid);
 void proc_exit(struct proc *proc, int status);
 void proc_yield(struct regs *r);
 void proc_clear_quantum();
-void proc_enable_waiting(u32 dev_id);
+void proc_enable_waiting(u32 id, enum proc_wait_type type);
+void proc_wait_for(u32 id, enum proc_wait_type type, s32 (*func)());
 struct proc *proc_make(void);
 
 #endif
diff --git a/kernel/main.c b/kernel/main.c
index 7466f5d..8739a53 100644
--- a/kernel/main.c
+++ b/kernel/main.c
@@ -36,7 +36,7 @@ void kernel_main(struct vid_info *vid_info)
 	timer_install();
 	keyboard_install();
 	mouse_install();
-	net_install();
+	/* net_install(); */
 
 	// Enable drivers
 	sti();