VFS ready function and read yielding

7 files changed, 111 insertions, 12 deletions

diff --git a/kernel/drivers/ide.c b/kernel/drivers/ide.c
index f3d0f6e..5a51cb8 100644
--- a/kernel/drivers/ide.c
+++ b/kernel/drivers/ide.c
@@ -147,6 +147,7 @@ void ata_probe(void)
 		struct vfs *vfs = malloc(sizeof(*vfs));
 		vfs->type = VFS_EXT2;
 		vfs->read = ext2_read;
+		vfs->ready = ext2_ready;
 		vfs->stat = ext2_stat;
 		dev->vfs = vfs;
 		vfs_mount(dev, "/");
diff --git a/kernel/drivers/keyboard.c b/kernel/drivers/keyboard.c
index 7f3247f..6936c22 100644
--- a/kernel/drivers/keyboard.c
+++ b/kernel/drivers/keyboard.c
@@ -2,12 +2,17 @@
 
 #include <cpu.h>
 #include <def.h>
+#include <fs.h>
 #include <interrupts.h>
 #include <mem.h>
 #include <print.h>
+#include <proc.h>
+#include <stack.h>
+#include <str.h>
 #include <sys.h>
 
 static struct event_keyboard *event = NULL;
+static struct stack *queue = NULL;
 
 static int state = 0;
 static int merged = 0;
@@ -33,10 +38,13 @@ void keyboard_handler()
 	event->magic = KEYBOARD_MAGIC;
 	event->press = (scancode & 0x80) == 0;
 	event->scancode = event->press ? scancode : scancode & ~0x80;
-	//event_trigger(EVENT_KEYBOARD, event);
+	stack_push_bot(queue, event);
 
 	state = 0;
 	merged = 0;
+
+	// TODO: Only enable waiting procs
+	proc_current()->state = PROC_RUNNING;
 }
 
 void keyboard_acknowledge(void)
@@ -52,8 +60,32 @@ void keyboard_rate(void)
 	outb(0x60, 0x0); // Rate{00000} Delay{00} 0
 }
 
+u32 keyboard_read(void *buf, u32 offset, u32 count, struct device *dev)
+{
+	(void)dev;
+	if (stack_empty(queue))
+		return 0;
+
+	struct event *e = stack_pop(queue);
+	memcpy(buf, (u8 *)e + offset, count);
+	return count;
+}
+
+u32 keyboard_ready()
+{
+	return !stack_empty(queue);
+}
+
 void keyboard_install(void)
 {
 	//keyboard_rate(); TODO: Fix keyboard rate?
 	irq_install_handler(1, keyboard_handler);
+
+	queue = stack_new();
+	struct device *dev = malloc(sizeof(*dev));
+	dev->name = strdup("kbd");
+	dev->type = DEV_CHAR;
+	dev->read = keyboard_read;
+	dev->ready = keyboard_ready;
+	device_add(dev);
 }
diff --git a/kernel/features/fs.c b/kernel/features/fs.c
index 13ed0c2..45e744c 100644
--- a/kernel/features/fs.c
+++ b/kernel/features/fs.c
@@ -154,9 +154,32 @@ u32 vfs_write(const char *path, void *buf, u32 offset, u32 count)
 
 u32 vfs_stat(const char *path, struct stat *buf)
 {
-	struct device *dev = vfs_find_dev(path);
-	assert(dev && dev->vfs && dev->vfs->stat);
-	return dev->vfs->stat(path, buf, dev);
+	while (*path == ' ')
+		path++;
+
+	struct mount_info *m = vfs_find_mount_info(path);
+	assert(m && m->dev && m->dev->vfs && m->dev->vfs->stat);
+
+	u32 len = strlen(m->path);
+	if (len > 1)
+		path += len;
+
+	return m->dev->vfs->stat(path, buf, m->dev);
+}
+
+u32 vfs_ready(const char *path)
+{
+	while (*path == ' ')
+		path++;
+
+	struct mount_info *m = vfs_find_mount_info(path);
+	assert(m && m->dev && m->dev->vfs && m->dev->vfs->ready);
+
+	u32 len = strlen(m->path);
+	if (len > 1)
+		path += len;
+
+	return m->dev->vfs->ready(path, m->dev);
 }
 
 void vfs_install(void)
@@ -176,7 +199,7 @@ void device_add(struct device *dev)
 	list_add(devices, dev);
 }
 
-struct device *device_get(u32 id)
+struct device *device_get_by_id(u32 id)
 {
 	struct node *iterator = devices->head;
 	while (iterator) {
@@ -187,11 +210,33 @@ struct device *device_get(u32 id)
 	return NULL;
 }
 
+struct device *device_get_by_name(const char *name)
+{
+	struct node *iterator = devices->head;
+	while (iterator) {
+		if (!strcmp(((struct device *)iterator->data)->name, name))
+			return iterator->data;
+		iterator = iterator->next;
+	}
+	return NULL;
+}
+
 u32 devfs_read(const char *path, void *buf, u32 offset, u32 count, struct device *dev)
 {
-	assert(dev && dev->read);
-	printf("%s - off: %d, cnt: %d, buf: %x, dev %x\n", path, offset, count, buf, dev);
-	return dev->read(buf, offset, count, dev);
+	struct device *target = device_get_by_name(path + 1);
+	if (!target || !target->read)
+		return 0;
+	return target->read(buf, offset, count, dev);
+}
+
+u32 devfs_ready(const char *path, struct device *dev)
+{
+	(void)dev;
+
+	struct device *target = device_get_by_name(path + 1);
+	if (!target || !target->ready)
+		return 0;
+	return target->ready();
 }
 
 void device_install(void)
@@ -201,6 +246,7 @@ void device_install(void)
 	struct vfs *vfs = malloc(sizeof(*vfs));
 	vfs->type = VFS_DEVFS;
 	vfs->read = devfs_read;
+	vfs->ready = devfs_ready;
 	struct device *dev = malloc(sizeof(*dev));
 	dev->name = "dev";
 	dev->type = DEV_CHAR;
@@ -406,3 +452,10 @@ u32 ext2_stat(const char *path, struct stat *buf, struct device *dev)
 
 	return 0;
 }
+
+u32 ext2_ready(const char *path, struct device *dev)
+{
+	(void)path;
+	(void)dev;
+	return 1;
+}
diff --git a/kernel/features/proc.c b/kernel/features/proc.c
index 79bc6c8..8fbb4c5 100644
--- a/kernel/features/proc.c
+++ b/kernel/features/proc.c
@@ -44,8 +44,12 @@ void scheduler(struct regs *regs)
 	} else if (((struct proc *)proc_list->head->data)->state == PROC_RUNNING) {
 		current = proc_list->head;
 	} else {
-		print("TODO: All processes are sleeping!\n"); // TODO!
-		/* loop(); */
+		/* sti(); */
+		/* hlt(); */
+		/* cli(); */
+		//print("TODO: All processes are sleeping!\n"); // TODO!
+		//loop();
+		return;
 	}
 
 	memcpy(regs, &((struct proc *)current->data)->regs, sizeof(struct regs));
diff --git a/kernel/features/syscall.c b/kernel/features/syscall.c
index dbb7033..c5570c3 100644
--- a/kernel/features/syscall.c
+++ b/kernel/features/syscall.c
@@ -37,7 +37,12 @@ void syscall_handler(struct regs *r)
 		break;
 	}
 	case SYS_READ: {
-		r->eax = (u32)vfs_read((char *)r->ebx, (void *)r->ecx, r->edx, r->esi);
+		if (vfs_ready((char *)r->ebx)) {
+			r->eax = (u32)vfs_read((char *)r->ebx, (void *)r->ecx, r->edx, r->esi);
+		} else {
+			proc_current()->state = PROC_SLEEPING;
+			scheduler(r);
+		}
 		break;
 	}
 	case SYS_WRITE: {
diff --git a/kernel/inc/fs.h b/kernel/inc/fs.h
index ff14361..1b2b073 100644
--- a/kernel/inc/fs.h
+++ b/kernel/inc/fs.h
@@ -20,6 +20,7 @@ struct device {
 	void *data;
 	u32 (*read)(void *buf, u32 offset, u32 count, struct device *dev);
 	u32 (*write)(void *buf, u32 offset, u32 count, struct device *dev);
+	u32 (*ready)();
 };
 
 void device_install(void);
@@ -38,6 +39,7 @@ struct vfs {
 	u32 (*read)(const char *path, void *buf, u32 offset, u32 count, struct device *dev);
 	u32 (*write)(const char *path, void *buf, u32 offset, u32 count, struct device *dev);
 	u32 (*stat)(const char *path, struct stat *buf, struct device *dev);
+	u32 (*ready)(const char *path, struct device *dev);
 };
 
 struct mount_info {
@@ -53,6 +55,7 @@ u32 vfs_mount(struct device *dev, const char *path);
 u32 vfs_read(const char *path, void *buf, u32 offset, u32 count);
 u32 vfs_write(const char *path, void *buf, u32 offset, u32 count);
 u32 vfs_stat(const char *path, struct stat *buf);
+u32 vfs_ready(const char *path);
 
 /**
  * EXT2
@@ -147,5 +150,6 @@ struct ext2_file {
 
 u32 ext2_read(const char *path, void *buf, u32 offset, u32 count, struct device *dev);
 u32 ext2_stat(const char *path, struct stat *buf, struct device *dev);
+u32 ext2_ready(const char *path, struct device *dev);
 
 #endif
diff --git a/libc/inc/sys.h b/libc/inc/sys.h
index e345ce8..14f83dd 100644
--- a/libc/inc/sys.h
+++ b/libc/inc/sys.h
@@ -96,7 +96,7 @@ static inline u32 getpid()
 	return buf;
 }
 
-// Hacky, one-digit solution - TODO!
+// Hacky one-digit solution - TODO!
 #include <mem.h>
 #include <str.h>
 static inline u32 pidof(const char *name)